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Sample records for ozone exposure daily

  1. Attenuated response to repeated daily ozone exposures in asthmatic subjects

    Energy Technology Data Exchange (ETDEWEB)

    Gong, H. Jr.; Linn, W.S. [Rancho Low Amigos Medical Center, Downey, CA (United States); McManus, M.S. [Univ. of California, Los Angeles, CA (United States)

    1997-01-01

    The development of attenuated response ({open_quotes}tolerance{close_quotes}) to daily ozone (O{sub 3}) exposures in the laboratory is well established in healthy adult volunteers. However, the capability of asthmatics to develop tolerance during multiday ozone exposures in unclear. We exposed 10 adult volunteers with mild asthma to 0.4 ppm O{sub 3} in filtered air for 3 h/d on 5 consecutive d. Two similar filtered-air exposures during the preceding week served as controls. Follow-up O{sub 3} exposures were performed 4 and 7 d after the most recent consecutive exposure. All exposures were performed in an environmental chamber at 31 {degrees}C and 35% relative humidity. The subjects performed moderate exercise (mean ventilation rate of 32 l/min) for 15 min of each half-hour. Responses were measured with spirometry and symptom evaluations before and after each exposure, and a bronchial reactivity test (methacholine challenge) was conducted after each exposure. All response measurements showed clinically and statistically significant day-to-day variation. Symptom and forced-expiratory-volume-in-1-s responses were similarly large on the 1st and 2nd O{sub 3} exposure days, after which they diminished progressively, approaching filtered air response levels by the 5th consecutive O{sub 3} day. This tolerance was partially lost 4 and 7 d later. Bronchial reactivity peaked after the first O{sub 3} exposure and remained somewhat elevated after all subsequent O{sub 3} exposures, relative to its control level following filtered-air exposures. Individual responses varied widely; more severe initial responses to O{sub 3} predicted less rapid attenuation. We concluded that asthmatics can develop tolerance to frequent high-level O{sub 3} exposures in much the same manner as normal subjects, although the process may be slower and less fully effective in asthmatics. 27 refs., 3 figs., 4 tabs.

  2. Ozone pollution and ozone biomonitoring in European cities. Part I: Ozone concentrations and cumulative exposure indices at urban and suburban sites

    DEFF Research Database (Denmark)

    Klumpp, A.; Ansel, W.; Klumpp, G.

    2006-01-01

    In the frame of a European research project on air quality in urban agglomerations, data on ozone concentrations from 23 automated urban and suburban monitoring stations in 11 cities from seven countries were analysed and evaluated. Daily and summer mean and maximum concentrations were computed...... based on hourly mean values, and cumulative ozone exposure indices (Accumulated exposure Over a Threshold of 40 ppb (AOT40), AOT20) were calculated. The diurnal profiles showed a characteristic pattern in most city centres, with minimum values in the early morning hours, a strong rise during the morning......, by contrast, maximum values were lower and diurnal variation was much smaller. Based on ozone concentrations as well as on cumulative exposure indices, a clear north-south gradient in ozone pollution, with increasing levels from northern and northwestern sites to central and southern European sites...

  3. Ambient Ozone Pollution and Daily Mortality: A Nationwide Study in 272 Chinese Cities.

    Science.gov (United States)

    Yin, Peng; Chen, Renjie; Wang, Lijun; Meng, Xia; Liu, Cong; Niu, Yue; Lin, Zhijing; Liu, Yunning; Liu, Jiangmei; Qi, Jinlei; You, Jinling; Zhou, Maigeng; Kan, Haidong

    2017-11-21

    Few large multicity studies have been conducted in developing countries to address the acute health effects of atmospheric ozone pollution. We explored the associations between ozone and daily cause-specific mortality in China. We performed a nationwide time-series analysis in 272 representative Chinese cities between 2013 and 2015. We used distributed lag models and over-dispersed generalized linear models to estimate the cumulative effects of ozone (lagged over 0-3 d) on mortality in each city, and we used hierarchical Bayesian models to combine the city-specific estimates. Regional, seasonal, and demographic heterogeneity were evaluated by meta-regression. At the national-average level, a 10-μg/m 3 increase in 8-h maximum ozone concentration was associated with 0.24% [95% posterior interval (PI): 0.13%, 0.35%], 0.27% (95% PI: 0.10%, 0.44%), 0.60% (95% PI: 0.08%, 1.11%), 0.24% (95% PI: 0.02%, 0.46%), and 0.29% (95% PI: 0.07%, 0.50%) higher daily mortality from all nonaccidental causes, cardiovascular diseases, hypertension, coronary diseases, and stroke, respectively. Associations between ozone and daily mortality due to respiratory and chronic obstructive pulmonary disease specifically were positive but imprecise and nonsignificant. There were no statistically significant differences in associations between ozone and nonaccidental mortality according to region, season, age, sex, or educational attainment. Our findings provide robust evidence of higher nonaccidental and cardiovascular mortality in association with short-term exposure to ambient ozone in China. https://doi.org/10.1289/EHP1849.

  4. Evaluation of ozone emissions and exposures from consumer products and home appliances.

    Science.gov (United States)

    Zhang, Q; Jenkins, P L

    2017-03-01

    Ground-level ozone can cause serious adverse health effects and environmental impacts. This study measured ozone emissions and impacts on indoor ozone levels and associated exposures from 17 consumer products and home appliances that could emit ozone either intentionally or as a by-product of their functions. Nine products were found to emit measurable ozone, one up to 6230 ppb at a distance of 5 cm (2 inches). One use of these products increased room ozone concentrations by levels up to 106 ppb (mean, from an ozone laundry system) and personal exposure concentrations of the user by 12-424 ppb (mean). Multiple cycles of use of one fruit and vegetable washer increased personal exposure concentrations by an average of 2550 ppb, over 28 times higher than the level of the 1-h California Ambient Air Quality Standard for ozone (0.09 ppm). Ozone emission rates ranged from 1.6 mg/h for a refrigerator air purifier to 15.4 mg/h for a fruit and vegetable washer. The use of some products was estimated to contribute up to 87% of total daily exposures to ozone. The results show that the use of some products may result in potential health impacts. © 2016 The Authors. Indoor Air published by John Wiley & Sons Ltd.

  5. Ozone's impact on public health: Contributions from indoor exposures to ozone and products of ozone-initiated chemistry

    DEFF Research Database (Denmark)

    Weschler, Charles J.

    2006-01-01

    OBJECTIVES: The associations between ozone concentrations measured outdoors and both morbidity and mortality may be partially due to indoor exposures to ozone and ozone-initiated oxidation products. In this article I examine the contributions of such indoor exposures to overall ozone-related heal...

  6. Ozone exposure increases respiratory epithelial permeability in humans

    International Nuclear Information System (INIS)

    Kehrl, H.R.; Vincent, L.M.; Kowalsky, R.J.; Horstman, D.H.; O'Neil, J.J.; McCartney, W.H.; Bromberg, P.A.

    1987-01-01

    Ozone is a respiratory irritant that has been shown to cause an increase in the permeability of the respiratory epithelium in animals. We used inhaled aerosolized /sup 99m/Tc-labeled diethylene triamine pentacetic acid (/sup 99m/Tc-DTPA) to investigate whether human respiratory epithelial permeability is similarly affected by exposure to ozone. In a randomized, crossover double-blinded study, 8 healthy, nonsmoking young men were exposed for 2 h to purified air and 0.4 ppm ozone while performing intermittent high intensity treadmill exercise (minute ventilation = 66.8 L/min). SRaw and FVC were measured before and at the end of exposures. Seventy-five minutes after the exposures, the pulmonary clearance of /sup 99m/Tc-DTPA was measured by sequential posterior lung imaging with a computer-assisted gamma camera. Ozone exposure caused respiratory symptoms in all 8 subjects and was associated with a 14 +/- 2.8% (mean +/- SEM) decrement in FVC (p less than 0.001) and a 71 +/- 22% increase in SRaw (p = 0.04). Compared with the air exposure day, 7 of the 8 subjects showed increased /sup 99m/Tc-DTPA clearance after the ozone exposure, with the mean value increasing from 0.59 +/- 0.08 to 1.75 +/- 0.43%/min (p = 0.03). These data show that ozone exposure sufficient to produce decrements in the pulmonary function of human subjects also causes an increase in /sup 99m/Tc-DTPA clearance

  7. Impact of temporal upscaling and chemical transport model horizontal resolution on reducing ozone exposure misclassification

    Science.gov (United States)

    Xu, Yadong; Serre, Marc L.; Reyes, Jeanette M.; Vizuete, William

    2017-10-01

    We have developed a Bayesian Maximum Entropy (BME) framework that integrates observations from a surface monitoring network and predictions from a Chemical Transport Model (CTM) to create improved exposure estimates that can be resolved into any spatial and temporal resolution. The flexibility of the framework allows for input of data in any choice of time scales and CTM predictions of any spatial resolution with varying associated degrees of estimation error and cost in terms of implementation and computation. This study quantifies the impact on exposure estimation error due to these choices by first comparing estimations errors when BME relied on ozone concentration data either as an hourly average, the daily maximum 8-h average (DM8A), or the daily 24-h average (D24A). Our analysis found that the use of DM8A and D24A data, although less computationally intensive, reduced estimation error more when compared to the use of hourly data. This was primarily due to the poorer CTM model performance in the hourly average predicted ozone. Our second analysis compared spatial variability and estimation errors when BME relied on CTM predictions with a grid cell resolution of 12 × 12 km2 versus a coarser resolution of 36 × 36 km2. Our analysis found that integrating the finer grid resolution CTM predictions not only reduced estimation error, but also increased the spatial variability in daily ozone estimates by 5 times. This improvement was due to the improved spatial gradients and model performance found in the finer resolved CTM simulation. The integration of observational and model predictions that is permitted in a BME framework continues to be a powerful approach for improving exposure estimates of ambient air pollution. The results of this analysis demonstrate the importance of also understanding model performance variability and its implications on exposure error.

  8. PARAMETER EVALUATION AND MODEL VALIDATION OF OZONE EXPOSURE ASSESSMENT USING HARVARD SOUTHERN CALIFORNIA CHRONIC OZONE EXPOSURE STUDY DATA

    Science.gov (United States)

    To examine factors influencing long-term ozone exposures by children living in urban communities, we analyzed longitudinal data on personal, indoor, and outdoor ozone concentrations as well as related housing and other questionnaire information collected in the one-year-long Harv...

  9. Exposure-Relevant Ozone Chemistry in Occupied Spaces

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, Beverly Kaye [Univ. of California, Berkeley, CA (United States)

    2009-04-01

    Ozone, an ambient pollutant, is transformed into other airborne pollutants in the indoor environment. In this dissertation, the type and amount of byproducts that result from ozone reactions with common indoor surfaces, surface residues, and vapors were determined, pollutant concentrations were related to occupant exposure, and frameworks were developed to predict byproduct concentrations under various indoor conditions. In Chapter 2, an analysis is presented of secondary organic aerosol formation from the reaction of ozone with gas-phase, terpene-containing consumer products in small chamber experiments under conditions relevant for residential and commercial buildings. The full particle size distribution was continuously monitored, and ultrafine and fine particle concentrations were in the range of 10 to>300 mu g m-3. Particle nucleation and growth dynamics were characterized.Chapter 3 presents an investigation of ozone reactions with aircraft cabin surfaces including carpet, seat fabric, plastics, and laundered and worn clothing fabric. Small chamber experiments were used to determine ozone deposition velocities, ozone reaction probabilities, byproduct emission rates, and byproduct yields for each surface category. The most commonly detected byproducts included C1?C10 saturated aldehydes and skin oil oxidation products. For all materials, emission rates were higher with ozone than without. Experimental results were used to predict byproduct exposure in the cabin and compare to other environments. Byproduct levels are predicted to be similar to ozone levels in the cabin, which have been found to be tens to low hundreds of ppb in the absence of an ozone converter. In Chapter 4, a model is presented that predicts ozone uptake by and byproduct emission from residual chemicals on surfaces. The effects of input parameters (residue surface concentration, ozone concentration, reactivity of the residue and the surface, near-surface airflow conditions, and

  10. Comparison of spatiotemporal prediction models of daily exposure of individuals to ambient nitrogen dioxide and ozone in Montreal, Canada.

    Science.gov (United States)

    Buteau, Stephane; Hatzopoulou, Marianne; Crouse, Dan L; Smargiassi, Audrey; Burnett, Richard T; Logan, Travis; Cavellin, Laure Deville; Goldberg, Mark S

    2017-07-01

    In previous studies investigating the short-term health effects of ambient air pollution the exposure metric that is often used is the daily average across monitors, thus assuming that all individuals have the same daily exposure. Studies that incorporate space-time exposures of individuals are essential to further our understanding of the short-term health effects of ambient air pollution. As part of a longitudinal cohort study of the acute effects of air pollution that incorporated subject-specific information and medical histories of subjects throughout the follow-up, the purpose of this study was to develop and compare different prediction models using data from fixed-site monitors and other monitoring campaigns to estimate daily, spatially-resolved concentrations of ozone (O 3 ) and nitrogen dioxide (NO 2 ) of participants' residences in Montreal, 1991-2002. We used the following methods to predict spatially-resolved daily concentrations of O 3 and NO 2 for each geographic region in Montreal (defined by three-character postal code areas): (1) assigning concentrations from the nearest monitor; (2) spatial interpolation using inverse-distance weighting; (3) back-extrapolation from a land-use regression model from a dense monitoring survey, and; (4) a combination of a land-use and Bayesian maximum entropy model. We used a variety of indices of agreement to compare estimates of exposure assigned from the different methods, notably scatterplots of pairwise predictions, distribution of differences and computation of the absolute agreement intraclass correlation (ICC). For each pairwise prediction, we also produced maps of the ICCs by these regions indicating the spatial variability in the degree of agreement. We found some substantial differences in agreement across pairs of methods in daily mean predicted concentrations of O 3 and NO 2 . On a given day and postal code area the difference in the concentration assigned could be as high as 131ppb for O 3 and 108ppb

  11. Modeled population exposures to ozone

    Data.gov (United States)

    U.S. Environmental Protection Agency — Population exposures to ozone from APEX modeling for combinations of potential future air quality and demographic change scenarios. This dataset is not publicly...

  12. [The effects of exposure to ozone on sperm quality in Wuhan].

    Science.gov (United States)

    Tian, X J; Wang, X C; Ye, B; Li, C L; Zhang, Y; Ma, L

    2017-03-06

    Objective: To evaluate the effects of exposure to ozone (O(3)) on sperm quality during different stages of spermatogenesis. Methods: All 1 780 subjects attending to the Reproductive Medicine Center in Renmin Hospital of Wuhan University were recruited from April, 4, 2013 to June, 30, 2015. The subjects were living in Wuhan more than 3 months before attending to the program, aged 20 to 40 years. Semen quality (sperm concentration and sperm count) were measured according to standardized protocols. Corresponding daily 8 hours average concentration of O(3), other polluted concentration, average temperature and relative humidity were collected in different time, including lag 0, 10, 70 and 90 d, and lag 0-9 d, lag 10-14 d, lag 70-90 d and lag 0-90 d. After controlling the age, BMI, education level and other confounders, generalized linear Model was used to investigate the association between O(3) and sperm quality during different stages of spermatogenesis. Results: Average daily concentration of O(3) during the study period was (114.20±74.88) μg/m(3) and the mean values of sperm concentration and count were (76.32±50.17) millions/ml and (164.77 ± 133.05) millions/sample, respectively. Exposure to O(3) was associated with decreasing sperm concentration and count. For every 1 μg/m(3) increase of O(3), the decrease of sperm concentration during lag 10, lag 0-9 and lag 10-14 days exposure windows were 0.040 (95% CI: 0.004-0.077) millions/ml, 0.081 (95% CI: 0.003-0.158) millions/ml and 0.059 (95% CI: 0.001-0.116) millions/ml, respectively. And the decrease of sperm count during lag 10, lag 0-9 days exposure windows were 0.105 (95% CI: 0.008-0.202) millions/sample and 0.221 (95% CI: 0.016-0.426) millions/sample. After stratification, in the ozone concentration sperm concentration was 0.249 (95% CI: 0.028-0.470) millions/ml. After sensitivity analysis, the effects of exposure to ozone on sperm concentration and sperm count remained relatively unchanged. Conclusion: Our

  13. Environmental ozone exposure and oxidative DNA damage in adult residents of Florence, Italy

    Energy Technology Data Exchange (ETDEWEB)

    Palli, Domenico, E-mail: d.palli@ispo.toscana.i [Molecular and Nutritional Epidemiology Unit, Cancer Prevention and Research Institute (ISPO), Via Cosimo il Vecchio 2, 50139 Florence (Italy); Sera, Francesco, E-mail: f.sera@ispo.toscana.i [Molecular and Nutritional Epidemiology Unit, Cancer Prevention and Research Institute (ISPO), Via Cosimo il Vecchio 2, 50139 Florence (Italy); Giovannelli, Lisa, E-mail: lisag@pharm.unifi.i [Department of Pharmacology, University of Florence, Viale G.Pieraccini 6, 50139 Florence (Italy); Masala, Giovanna, E-mail: g.masala@ispo.toscana.i [Molecular and Nutritional Epidemiology Unit, Cancer Prevention and Research Institute (ISPO), Via Cosimo il Vecchio 2, 50139 Florence (Italy); Grechi, Daniele [Regional Environmental Protection Agency of Tuscany (ARPAT), Via Porpora 22, 50144 Florence (Italy); Bendinelli, Benedetta, E-mail: b.bendinelli@ispo.toscana.i [Molecular and Nutritional Epidemiology Unit, Cancer Prevention and Research Institute (ISPO), Via Cosimo il Vecchio 2, 50139 Florence (Italy); Caini, Saverio, E-mail: s.caini@ispo.toscana.i [Molecular and Nutritional Epidemiology Unit, Cancer Prevention and Research Institute (ISPO), Via Cosimo il Vecchio 2, 50139 Florence (Italy); Dolara, Piero, E-mail: piero.dolara@unifi.i [Department of Pharmacology, University of Florence, Viale G.Pieraccini 6, 50139 Florence (Italy); Saieva, Calogero, E-mail: c.saieva@ispo.toscana.i [Molecular and Nutritional Epidemiology Unit, Cancer Prevention and Research Institute (ISPO), Via Cosimo il Vecchio 2, 50139 Florence (Italy)

    2009-05-15

    In 71 adults residing in Florence, Italy, enrolled in a prospective study, we investigated the correlation between individual levels of oxidative DNA damage detected by the Comet assay in circulating lymphocytes, and a specific ozone exposure score calculated in 10 different time-windows (0-5 to 0-90 days) before blood drawing, based on daily measurements provided by the local environmental monitoring system. Overall, statistically significant positive correlations between average ozone concentrations and DNA damage emerged in almost all time-windows considered; correlations were more evident among males, non-smokers, and traffic-exposed workers. Multivariate regression analyses taking into account selected individual characteristics, showed an independent effect on DNA damage of average ozone concentrations in the last 60-90 days before blood drawing. Local residents showed a divergent pattern with correlations restricted to shorter time-windows. Our results suggest that ozone concentrations at ground levels modulate oxidative DNA damage in circulating lymphocytes of residents of polluted areas. - Ozone concentrations over the 60-90 days before blood drawing correlated with DNA damage in circulating lymphocytes of adults living in the metropolitan area of Florence, Italy.

  14. Environmental ozone exposure and oxidative DNA damage in adult residents of Florence, Italy

    International Nuclear Information System (INIS)

    Palli, Domenico; Sera, Francesco; Giovannelli, Lisa; Masala, Giovanna; Grechi, Daniele; Bendinelli, Benedetta; Caini, Saverio; Dolara, Piero; Saieva, Calogero

    2009-01-01

    In 71 adults residing in Florence, Italy, enrolled in a prospective study, we investigated the correlation between individual levels of oxidative DNA damage detected by the Comet assay in circulating lymphocytes, and a specific ozone exposure score calculated in 10 different time-windows (0-5 to 0-90 days) before blood drawing, based on daily measurements provided by the local environmental monitoring system. Overall, statistically significant positive correlations between average ozone concentrations and DNA damage emerged in almost all time-windows considered; correlations were more evident among males, non-smokers, and traffic-exposed workers. Multivariate regression analyses taking into account selected individual characteristics, showed an independent effect on DNA damage of average ozone concentrations in the last 60-90 days before blood drawing. Local residents showed a divergent pattern with correlations restricted to shorter time-windows. Our results suggest that ozone concentrations at ground levels modulate oxidative DNA damage in circulating lymphocytes of residents of polluted areas. - Ozone concentrations over the 60-90 days before blood drawing correlated with DNA damage in circulating lymphocytes of adults living in the metropolitan area of Florence, Italy.

  15. Ozone exposure, uptake, and response of different-sized black cherry trees

    Science.gov (United States)

    Todd S. Frederickson; John M. Skelly; Kim C. Steiner; Thomas E. Kolb

    1996-01-01

    Differences in exposure, uptake and relative sensitivity to ozone between seedling, sapling, and canopy black cherry (Prunus serotina Ehrh.) trees were characterized during two growing seasons in north central Pennsylvania. Open-grown trees of all sizes received a similar amount of ozone exposure. Seedlings had greater foliar ozone injury, expressed...

  16. Systemic metabolic derangement, pulmonary effects, and insulin insufficiency following subchronic ozone exposure in rats

    International Nuclear Information System (INIS)

    Miller, Desinia B.; Snow, Samantha J.; Henriquez, Andres; Schladweiler, Mette C.; Ledbetter, Allen D.; Richards, Judy E.; Andrews, Debora L.; Kodavanti, Urmila P.

    2016-01-01

    Acute ozone exposure induces a classical stress response with elevated circulating stress hormones along with changes in glucose, protein and lipid metabolism in rats, with similar alterations in ozone-exposed humans. These stress-mediated changes over time have been linked to insulin resistance. We hypothesized that acute ozone-induced stress response and metabolic impairment would persist during subchronic episodic exposure and induce peripheral insulin resistance. Male Wistar Kyoto rats were exposed to air or 0.25 ppm or 1.00 ppm ozone, 5 h/day, 3 consecutive days/week (wk) for 13 wks. Pulmonary, metabolic, insulin signaling and stress endpoints were determined immediately after 13 wk or following a 1 wk recovery period (13 wk + 1 wk recovery). We show that episodic ozone exposure is associated with persistent pulmonary injury and inflammation, fasting hyperglycemia, glucose intolerance, as well as, elevated circulating adrenaline and cholesterol when measured at 13 wk, however, these responses were largely reversible following a 1 wk recovery. Moreover, the increases noted acutely after ozone exposure in non-esterified fatty acids and branched chain amino acid levels were not apparent following a subchronic exposure. Neither peripheral or tissue specific insulin resistance nor increased hepatic gluconeogenesis were present after subchronic ozone exposure. Instead, long-term ozone exposure lowered circulating insulin and severely impaired glucose-stimulated beta-cell insulin secretion. Thus, our findings in young-adult rats provide potential insights into epidemiological studies that show a positive association between ozone exposures and type 1 diabetes. Ozone-induced beta-cell dysfunction may secondarily contribute to other tissue-specific metabolic alterations following chronic exposure due to impaired regulation of glucose, lipid, and protein metabolism. - Highlights: • Subchronic episodic ozone exposure caused pulmonary and metabolic effects. • These

  17. Systemic metabolic derangement, pulmonary effects, and insulin insufficiency following subchronic ozone exposure in rats

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Desinia B. [Curriculum in Toxicology, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina (United States); Snow, Samantha J. [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Henriquez, Andres [Curriculum in Toxicology, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina (United States); Schladweiler, Mette C.; Ledbetter, Allen D.; Richards, Judy E.; Andrews, Debora L. [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Kodavanti, Urmila P., E-mail: kodavanti.urmila@epa.gov [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States)

    2016-09-01

    Acute ozone exposure induces a classical stress response with elevated circulating stress hormones along with changes in glucose, protein and lipid metabolism in rats, with similar alterations in ozone-exposed humans. These stress-mediated changes over time have been linked to insulin resistance. We hypothesized that acute ozone-induced stress response and metabolic impairment would persist during subchronic episodic exposure and induce peripheral insulin resistance. Male Wistar Kyoto rats were exposed to air or 0.25 ppm or 1.00 ppm ozone, 5 h/day, 3 consecutive days/week (wk) for 13 wks. Pulmonary, metabolic, insulin signaling and stress endpoints were determined immediately after 13 wk or following a 1 wk recovery period (13 wk + 1 wk recovery). We show that episodic ozone exposure is associated with persistent pulmonary injury and inflammation, fasting hyperglycemia, glucose intolerance, as well as, elevated circulating adrenaline and cholesterol when measured at 13 wk, however, these responses were largely reversible following a 1 wk recovery. Moreover, the increases noted acutely after ozone exposure in non-esterified fatty acids and branched chain amino acid levels were not apparent following a subchronic exposure. Neither peripheral or tissue specific insulin resistance nor increased hepatic gluconeogenesis were present after subchronic ozone exposure. Instead, long-term ozone exposure lowered circulating insulin and severely impaired glucose-stimulated beta-cell insulin secretion. Thus, our findings in young-adult rats provide potential insights into epidemiological studies that show a positive association between ozone exposures and type 1 diabetes. Ozone-induced beta-cell dysfunction may secondarily contribute to other tissue-specific metabolic alterations following chronic exposure due to impaired regulation of glucose, lipid, and protein metabolism. - Highlights: • Subchronic episodic ozone exposure caused pulmonary and metabolic effects. • These

  18. Effects of ozone exposure on lung function in man: a review

    Energy Technology Data Exchange (ETDEWEB)

    Folinsbee, L J

    1981-01-01

    Ozone, an important component of photochemical smog, has a decided impact on lung function in man. In this review, the effects of zone on human lung function are discussed with particular attention to levels which are near the threshold of producing no effect. Attempts to define dose-response relationships and effects on sensitive subject populations are described. The relationship between exercise and ozone toxicity is presented in addition to the potential impact of ambient ozone exposure on athletic performance. Effects of ozone on respiratory symptoms and the interaction of ozone with other pollutants are briefly examined. Considerable attention has been directed at the phenomenon of adaptation to repeated ozone exposure and to possible mechanism of action of ozone.

  19. Effects of ozone exposures on epicuticular wax of ponderosa pine needles

    International Nuclear Information System (INIS)

    Bytnerowicz, A.; Turunen, M.

    1994-01-01

    Two-year-old ponderosa pine (Pinus ponderosa L.) seedlings were exposed during the 1989 and 1990 growing seasons to ozone in open-top chambers placed in a forested location at Shirley Meadow, Greenhorn Mountain Range, Sierra Nevada. The ozone treatments were as follows: charcoal-filtered air (CF); charcoal-filtered air with addition of ambient concentrations of ozone (CF + O 3 ); and charcoal-filtered air with addition of doubled concentrations of ozone (CF + 2 x O 3 ). Ozone effects on ponderosa pine seedlings progressed and accumulated over two seasons of exposure. Throughout the first season, increased visible injury and accelerated senescence of the foliage were noted. Subsequently, during the second season of ozone exposure, various physiological and biochemical changes in the foliage took place. All these changes led to reduced growth and biomass of the seedlings. Epistomatal waxes of needles from the CA + 2 x O 3 treatment had an occluded appearance. This phenomenon may be caused by earlier phenological development of needles from the high-ozone treatments and disturbed development and synthesis of waxes. It may also be caused by chemical degradation of waxes by exposures to high ozone concentrations. (orig.)

  20. Spatiotemporal prediction of daily ambient ozone levels across China using random forest for human exposure assessment.

    Science.gov (United States)

    Zhan, Yu; Luo, Yuzhou; Deng, Xunfei; Grieneisen, Michael L; Zhang, Minghua; Di, Baofeng

    2018-02-01

    In China, ozone pollution shows an increasing trend and becomes the primary air pollutant in warm seasons. Leveraging the air quality monitoring network, a random forest model is developed to predict the daily maximum 8-h average ozone concentrations ([O 3 ] MDA8 ) across China in 2015 for human exposure assessment. This model captures the observed spatiotemporal variations of [O 3 ] MDA8 by using the data of meteorology, elevation, and recent-year emission inventories (cross-validation R 2  = 0.69 and RMSE = 26 μg/m 3 ). Compared with chemical transport models that require a plenty of variables and expensive computation, the random forest model shows comparable or higher predictive performance based on only a handful of readily-available variables at much lower computational cost. The nationwide population-weighted [O 3 ] MDA8 is predicted to be 84 ± 23 μg/m 3 annually, with the highest seasonal mean in the summer (103 ± 8 μg/m 3 ). The summer [O 3 ] MDA8 is predicted to be the highest in North China (125 ± 17 μg/m 3 ). Approximately 58% of the population lives in areas with more than 100 nonattainment days ([O 3 ] MDA8 >100 μg/m 3 ), and 12% of the population are exposed to [O 3 ] MDA8 >160 μg/m 3 (WHO Interim Target 1) for more than 30 days. As the most populous zones in China, the Beijing-Tianjin Metro, Yangtze River Delta, Pearl River Delta, and Sichuan Basin are predicted to be at 154, 141, 124, and 98 nonattainment days, respectively. Effective controls of O 3 pollution are urgently needed for the highly-populated zones, especially the Beijing-Tianjin Metro with seasonal [O 3 ] MDA8 of 140 ± 29 μg/m 3 in summer. To the best of the authors' knowledge, this study is the first statistical modeling work of ambient O 3 for China at the national level. This timely and extensively validated [O 3 ] MDA8 dataset is valuable for refining epidemiological analyses on O 3 pollution in China. Copyright © 2017 Elsevier Ltd. All rights

  1. Sampling Ozone Exposure of Canadian Forests at Different Scales: Some Case Studies

    Directory of Open Access Journals (Sweden)

    R.M. Cox

    2001-01-01

    Full Text Available The use of passive samplers in extensive monitoring, such as that used in national forest health monitoring plots, indicates that these devices are able to determine both spatial and temporal differences in ozone exposure of the plots. This allows for categorisation of the plots and the potential for cause-effect analysis of certain forest health responses. Forest exposure along a gradient of air pollution deposition demonstrates large variation in accumulated exposures. The efficacy of using passive samplers for in situ monitoring of forest canopy exposure was also demonstrated. The sampler data produced weak relationships with ozone values from the nearest �continuous� monitor, even though data from colocated samplers showed strong relationships. This spatial variation and the apparent effect of elevation on ozone exposure demonstrate the importance of topography and tree canopy characteristics in plant exposure on a regional scale. In addition, passive sampling may identify the effects of local pollutant gases, such as NO, which may scavenge ozone locally only to increase the production of this secondary pollutant downwind, as atmospheric reactions redress the equilibrium between concentrations of this precursor and those of the generated ozone. The use of passive samplers at the stand level is able to resolve vertical profiles within the stand and edge effects that are important in exposure of understorey and ground flora. Recent case studies using passive samplers to determine forest exposure to ozone indicate a great potential for the development of spatial models on a regional, landscape, and stand level scale.

  2. The relationships between short-term exposure to particulate matter and mortality in Korea: impact of particulate matter exposure metrics for sub-daily exposures

    International Nuclear Information System (INIS)

    Son, Ji-Young; Bell, Michelle L

    2013-01-01

    Most studies of short-term particulate matter (PM) exposure use 24 h averages. However, other pollutants have stronger effects in shorter timeframes, which has influenced policy (e.g., ozone 8 h maximum). The selection of appropriate exposure timeframes is important for effective regulation. The US EPA identified health effects for sub-daily PM exposures as a critical research need. Unlike most areas, Seoul, Korea has hourly measurements of PM 10 , although not PM 2.5 . We investigated PM 10 and mortality (total, cardiovascular, respiratory) in Seoul (1999–2009) considering sub-daily exposures: 24 h, daytime (7 am–8 pm), morning (7–10 am), nighttime (8 pm–7 am), and 1 h daily maximum. We applied Poisson generalized linear modeling adjusting for temporal trends and meteorology. All PM 10 metrics were significantly associated with total mortality. Compared to other exposure timeframes, morning exposure had the most certain effect on total mortality (based on statistical significance). Increases of 10 μg m −3 in 24 h, daytime, morning, nighttime, and 1 h maximum PM 10 were associated with 0.15% (95% confidence interval 0.02–0.28%), 0.14% (0.01–0.27%), 0.10% (0.03–0.18%), 0.12% (0.03–0.22%), and 0.10% (0.00–0.21%) increases in total mortality, respectively. PM 10 was significantly associated with cardiovascular mortality for 24 h, morning, and nighttime exposures. We did not identify significant associations with respiratory mortality. The results support use of a 24 h averaging time as an appropriate metric for health studies and regulation, particularly for PM 10 and mortality. (letter)

  3. Chloroplastic responses of ponderosa pine (Pinus ponderosa) seedlings to ozone exposure.

    Science.gov (United States)

    Anderson, Paul D; Palmer, Brent; Houpis, James L J; Smith, Mary K; Pushnik, James C

    2003-06-01

    Integrity of chloroplast membranes is essential to photosynthesis. Loss of thylakoid membrane integrity has been proposed as a consequence of ozone (O(3)) exposure and therefore may be a mechanistic basis for decreased photosynthetic rates commonly associated with ozone exposure. To investigate this hypothesis, Pinus ponderosa seedlings were exposed to ambient air or ozone concentrations maintained at 0.15 or 0.30 microliter l(-1) for 10 h day(-1) for 51 days during their second growing season. Over the course of the study, foliage samples were periodically collected for thylakoid membrane, chlorophyll and protein analyses. Additionally, gas-exchange measurements were made in conjunction with foliage sampling to verify that observed chloroplastic responses were associated with ozone-induced changes in photosynthesis. Needles exposed to elevated ozone exhibited decreases in chlorophyll a and b content. The decreases were dependent on the duration and intensity of ozone exposure. When based on equal amounts of chlorophyll, ozone-exposed sample tissue exhibited an increase in total protein. When based on equal amounts of protein, ozone-exposed samples exhibited an increase in 37 kDa proteins, possibly consisting of breakdown products, and a possible decrease in 68 kDa proteins, Rubisco small subunit. There was also a change in the ratio of Photosystem I protein complexes CPI and CPII that may have contributed to decreased photosynthesis. Net photosynthetic rates were decreased in the high ozone treatment suggesting that observed structural and biochemical changes in the chloroplast were associated with alterations of the photosynthetic process.

  4. CORRELATION BETWEEN OZONE EXPOSURE AND VISIBLE FOLIAR INJURY IN PONDEROSA AND JEFFREY PINES. (R825433)

    Science.gov (United States)

    Ozone exposure was related to ozone-induced visible foliar injury in ponderosa and Jeffrey pines growing on the western slopes of the Sierra Nevada Mountains of California. Measurements of ozone exposure, chlorotic mottle and fascicle retention were collected during the years ...

  5. Iron decreases biological effects of ozone exposure

    Science.gov (United States)

    CONTEXT: Ozone (0(3)) exposure is associated with a disruption of iron homeostasis and increased availability of this metal which potentially contributes to an oxidative stress and biologicaleffects. OBJECTIVE: We tested the postulate that increased concentrations of iron in c...

  6. Ozone exposure of a weed community produces adaptive changes in seed populations of Spergula arvensis.

    Directory of Open Access Journals (Sweden)

    Jennifer B Landesmann

    Full Text Available Tropospheric ozone is one of the major drivers of global change. This stress factor alters plant growth and development. Ozone could act as a selection pressure on species communities composition, but also on population genetic background, thus affecting life history traits. Our objective was to evaluate the consequences of prolonged ozone exposure of a weed community on phenotypic traits of Spergulaarvensis linked to persistence. Specifically, we predicted that the selection pressure exerted by high ozone concentrations as well as the concomitant changes in the weed community would drive population adaptive changes which will be reflected on seed germination, dormancy and longevity. In order to test seed viability and dormancy level, we conducted germination experiments for which we used seeds produced by S. arvensis plants grown within a weed community exposed to three ozone treatments during four years (0, 90 and 120 ppb. We also performed a soil seed bank experiment to test seed longevity with seeds coming from both the four-year ozone exposure experiment and from a short-term treatment conducted at ambient and added ozone concentrations. We found that prolonged ozone exposure produced changes in seed germination, dormancy and longevity, resulting in three S. arvensis populations. Seeds from the 90 ppb ozone selection treatment had the highest level of germination when stored at 75% RH and 25 °C and then scarified. These seeds showed the lowest dormancy level when being subjected to 5 ºC/5% RH and 25 ºC/75% followed by 5% RH storage conditions. Furthermore, ozone exposure increased seed persistence in the soil through a maternal effect. Given that tropospheric ozone is an important pollutant in rural areas, changes in seed traits due to ozone exposure could increase weed persistence in fields, thus affecting weed-crop interactions, which could ultimately reduce crop production.

  7. Ozone exposure of a weed community produces adaptive changes in seed populations of Spergula arvensis.

    Science.gov (United States)

    Landesmann, Jennifer B; Gundel, Pedro E; Martínez-Ghersa, M Alejandra; Ghersa, Claudio M

    2013-01-01

    Tropospheric ozone is one of the major drivers of global change. This stress factor alters plant growth and development. Ozone could act as a selection pressure on species communities composition, but also on population genetic background, thus affecting life history traits. Our objective was to evaluate the consequences of prolonged ozone exposure of a weed community on phenotypic traits of Spergulaarvensis linked to persistence. Specifically, we predicted that the selection pressure exerted by high ozone concentrations as well as the concomitant changes in the weed community would drive population adaptive changes which will be reflected on seed germination, dormancy and longevity. In order to test seed viability and dormancy level, we conducted germination experiments for which we used seeds produced by S. arvensis plants grown within a weed community exposed to three ozone treatments during four years (0, 90 and 120 ppb). We also performed a soil seed bank experiment to test seed longevity with seeds coming from both the four-year ozone exposure experiment and from a short-term treatment conducted at ambient and added ozone concentrations. We found that prolonged ozone exposure produced changes in seed germination, dormancy and longevity, resulting in three S. arvensis populations. Seeds from the 90 ppb ozone selection treatment had the highest level of germination when stored at 75% RH and 25 °C and then scarified. These seeds showed the lowest dormancy level when being subjected to 5 ºC/5% RH and 25 ºC/75% followed by 5% RH storage conditions. Furthermore, ozone exposure increased seed persistence in the soil through a maternal effect. Given that tropospheric ozone is an important pollutant in rural areas, changes in seed traits due to ozone exposure could increase weed persistence in fields, thus affecting weed-crop interactions, which could ultimately reduce crop production.

  8. Within season and carry-over effects following exposure of grassland species mixtures to increasing background ozone

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, Felicity, E-mail: fhay@ceh.ac.uk [Centre for Ecology and Hydrology, Environment Centre Wales, Deiniol Road, Bangor, Gwynedd LL57 2UW (United Kingdom); Mills, Gina; Harmens, Harry; Wyness, Kirsten [Centre for Ecology and Hydrology, Environment Centre Wales, Deiniol Road, Bangor, Gwynedd LL57 2UW (United Kingdom)

    2011-10-15

    Few studies have investigated effects of increased background ozone in the absence of episodic peaks, despite a predicted increase throughout the northern hemisphere over the coming decades. In this study Leontodon hispidus was grown with Anthoxanthum odoratum or Dactylis glomerata and exposed in the UK to one of eight background ozone concentrations for 20 weeks in solardomes. Seasonal mean ozone concentrations ranged from 21.4 to 102.5 ppb. Ozone-induced senescence of L. hispidus was enhanced when grown with the more open canopy of A. odoratum compared to the denser growing D. glomerata. There was increased cover with increasing ozone exposure for both A. odoratum and D. glomerata, which resulted in an increase in the grass:Leontodon cover ratio in both community types. Carry-over effects of the ozone exposure were observed, including delayed winter die-back of L. hispidus and acceleration in the progression from flowers to seed-heads in the year following ozone exposure. - Highlights: > Increased background ozone concentrations increased the grass:forb cover ratio. > Competing grass species influenced ozone enhanced senescence of Leontodon hispidus. > Ozone delayed winter die-back of leaves of L. hispidus. > Flowering was accelerated for L. hispidus in the year following ozone exposure. - Increased background ozone enhanced leaf senescence and caused carry-over effects including reduced winter die-back and an acceleration in flowering the next year.

  9. Compensation processes of Aleppo pine (Pinus halepensis Mill.) to ozone exposure and drought stress

    International Nuclear Information System (INIS)

    Inclan, R.; Gimeno, B.S.; Dizengremel, P.; Sanchez, M.

    2005-01-01

    A long-term experiment was performed to study the effects of O 3 and drought-stress (DS) on Aleppo pine seedlings (Pinus halepensis Mill.) exposed in open-top chambers. Ozone reduced gas exchange rates, ribulose-1,5-biphosphate carboxylase/oxygenase activity (Rubisco), aboveground C and needle N concentrations and C/N ratio and Ca concentrations of the twigs under 3 mm (twigs Pd ), C/N ratio, twigs<3 Ca, plant growth, aerial biomass and increased N, twigs with a diameter above 3 mm P and Mg concentrations. The combined exposure to both stresses increased N concentrations of twigs<3 and roots and aboveground biomass K content and decreased root C, maximum daily assimilation rate and instantaneous water use efficiency. The sensitivity of Aleppo pine to both stresses is determined by plant internal resource allocation and compensation mechanisms to cope with stress. - Ozone and drought stress induce the activation of similar processes related to C and N metabolism

  10. TOMS/Nimbus-7 Total Ozone Aerosol Index UV-Reflectivity UV-B Erythemal Irradiances Daily L3 Global 1x1.25 deg V008

    Data.gov (United States)

    National Aeronautics and Space Administration — The Total Ozone Mapping Spectrometer (TOMS) version 8 Daily Gridded Data consist of daily, global coverage of total column ozone, aerosol index, Lambertian effective...

  11. Ground-level ozone pollution and its health impacts in China

    Science.gov (United States)

    Liu, Huan; Liu, Shuai; Xue, Boru; Lv, Zhaofeng; Meng, Zhihang; Yang, Xiaofan; Xue, Tao; Yu, Qiao; He, Kebin

    2018-01-01

    In recent years, ground-level ozone pollution in China has become an increasingly prominent problem. This study simulated and analyzed spatiotemporal distribution of ozone and exposure level by the Weather Research and Forecasting (WRF)-Community Multiscale Air Quality (CMAQ) models and monitoring data from 1516 national air quality monitoring stations in China during 2015. The simulation results show that the Sichuan Basin, Shandong, Shanxi, Henan, Anhui, Qinghai-Tibetan Plateau, Yangtze River Delta (YRD), Pearl River Delta (PRD) and Beijing-Tianjin-Hebei (BTH) region had relatively high average annual concentrations of ozone. The regions with more than 10% nonattainment days of 160 μg/m3 (daily maximum 8-h) are mainly concentrated in BTH, Shandong Peninsula and YRD, where large seasonal variations were also found. Exposure levels were calculated based on population data and simulated ozone concentrations. The cumulative population exposed to daily maximum 8-h concentration greater than or equal to 100 μg/m3 was 816.04 million, 61.17% of the total. Three methods were used to estimate the mortality of chronic obstructive pulmonary disease (COPD) attributable to ozone. A comparative study using different exposure concentrations and threshold concentrations found large variations among these methods, although they were all peer-reviewed methods. The estimated mortality of COPD caused by ozone in China in 2015 ranged from 55341 to 80280, which mainly distributed in Beijing, Shandong, Henan, Hubei and Sichuan Province, the YRD and PRD region.

  12. Chronic bronchiolitis in non-human primates after prolonged ozone exposure

    International Nuclear Information System (INIS)

    Eustis, S.L.

    1979-01-01

    Bonnet monkeys (Macaca radiata) were exposed to 0.0, 0.5, and 0.8 ppM ozone for 7, 28, or 90 consecutive d, eight h per d. Changes in the lung evoked by prolonged oxidant exposure were evaluated by light microscopy, scanning electron microscopy, transmission electron microscopy, autoradiography, and morphometry. Morphological changes were principally characterized as a low-grade chronic respiratory bronchiolitis. Proximal generations of respiratory bronchioles were the most consistently affected region of the pulmonary acinus. Major features of the bronchiolitis were intraluminal accumulations of macrophages and hypertrophy and hyperplasia of cuboidal bronchiolar epithelial cells. The degree of inflammation was greatest at the 0.8 ppM ozone concentration at each exposure period. The number of inflammatory cells observed at 90 d, however, was about one-half that observed at 7 d. Tritiated thymidine labeling and differential cell counts of respiratory bronchiolar epithelium demonstrated a proliferative response and an increase in the proportion of cubiodal bronchiolar cells which presumably function as the progenitor cell during cell renewal and repair of the epithelium. The labeling index remained elevated above control values through 90 d of ozone exposure despite a reduction below 7 d values at both 28 and 90 d. The epithelial hyperplasia persisted through 90 d at a level similar to but slightly above that present at 7 d. Since cell differentials remained shifted at 28 and 90 d, it appears that persistent ozone exposure delayed maturation and transformation of cubiodal bronchiolar cells to their mature phenotype

  13. Determinants of personal exposure to ozone in school children. Results from a panel study in Greece.

    Science.gov (United States)

    Dimakopoulou, Konstantina; Grivas, Georgios; Samoli, Evangelia; Rodopoulou, Sophia; Spyratos, Dionisis; Papakosta, Despoina; Karakatsani, Anna; Chaloulakou, Archontoula; Katsouyanni, Klea

    2017-04-01

    In the wider framework of the RESPOZE (ReSPiratory effects of OZone Exposure in Greek children) panel study, we investigated possible determinants of O 3 exposure of school children, measured with personal passive samplers, in Athens and Thessaloniki, Greece. Personal exposure to O 3 was measured for five weeks spread along the academic year 2013-14, in 186 school children in Athens and Thessaloniki, Greece. At the same time, at-school outdoor measurements were performed and ambient levels of 8-h daily maximum O 3 from fixed sites were collected. We also collected information on lifestyle and housing characteristics through an extended general questionnaire (GQ) and each participant completed daily time activity diaries (TADs) during the study period. Mean outdoor concentrations were higher during the warmer months, in the suburbs of the cities and in Athens. Personal exposure concentrations were significantly lower compared to outdoor. Daily levels of at-school outdoor and ambient levels of O 3 from fixed sites were significant determinants of personal exposure to O 3 . For a 10μg/m 3 increase in at-school outdoor O 3 concentrations and PM 10 measurements a 20.9% (95% CI: 13%, 28%) increase in personal exposure to O 3 was found. For a half an hour more spent in transportation an average increase of 7% (95% CI: 0.3%, 14.6%) in personal exposure to O 3 was observed. Among other possible determinants, time spent in transportation (TAD variable) and duration of open windows were the ones associated with personal O 3 exposure levels. Our results support the use of outdoor and ambient measurements from fixed sites in epidemiological studies as a proxy of personal exposure to O 3 , but this has to be calibrated taking into account personal measurements and time-activity patterns. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Controlled human exposure to indoor air, dust, and ozone; XDOZ

    DEFF Research Database (Denmark)

    Elholm, Grethe; Bønløkke, Jakob; Schlünssen, Vivi

    2017-01-01

    . All participants were subjected to four different exposure scenarios in the climate chamber.Exp. 1: Dust (250 – 300 µg/m3)Exp. 2: Ozone (100 ppb)Exp. 3: Dust (250 – 300 µg/m3) + ozone (100 ppb)Exp. 4: Filtered air (<20µg/m3)The exposure time was 5½ hours for each session.The health effects were...... evaluated at baseline and specific follow-up times in relation to selected respiratory and cardiovascular outcomes, such as; nasal volume, exhaled nitric oxide (FENO), spirometry (FEV1 and FVC), exhaled breath condensate (EBC), nasal lavage, blood samples, EndoPat. Questionnaires were used for assessment...

  15. Exposure to ozone modulates human airway protease/antiprotease balance contributing to increased influenza A infection.

    Directory of Open Access Journals (Sweden)

    Matthew J Kesic

    Full Text Available Exposure to oxidant air pollution is associated with increased respiratory morbidities and susceptibility to infections. Ozone is a commonly encountered oxidant air pollutant, yet its effects on influenza infections in humans are not known. The greater Mexico City area was the primary site for the spring 2009 influenza A H1N1 pandemic, which also coincided with high levels of environmental ozone. Proteolytic cleavage of the viral membrane protein hemagglutinin (HA is essential for influenza virus infectivity. Recent studies suggest that HA cleavage might be cell-associated and facilitated by the type II transmembrane serine proteases (TTSPs human airway trypsin-like protease (HAT and transmembrane protease, serine 2 (TMPRSS2, whose activities are regulated by antiproteases, such as secretory leukocyte protease inhibitor (SLPI. Based on these observations, we sought to determine how acute exposure to ozone may modulate cellular protease/antiprotease expression and function, and to define their roles in a viral infection. We utilized our in vitro model of differentiated human nasal epithelial cells (NECs to determine the effects of ozone on influenza cleavage, entry, and replication. We show that ozone exposure disrupts the protease/antiprotease balance within the airway liquid. We also determined that functional forms of HAT, TMPRSS2, and SLPI are secreted from human airway epithelium, and acute exposure to ozone inversely alters their expression levels. We also show that addition of antioxidants significantly reduces virus replication through the induction of SLPI. In addition, we determined that ozone-induced cleavage of the viral HA protein is not cell-associated and that secreted endogenous proteases are sufficient to activate HA leading to a significant increase in viral replication. Our data indicate that pre-exposure to ozone disrupts the protease/antiprotease balance found in the human airway, leading to increased influenza susceptibility.

  16. Structural and functional localization of airway effects from episodic exposure of infant monkeys to allergen and/or ozone

    International Nuclear Information System (INIS)

    Joad, Jesse P.; Kott, Kayleen S.; Bric, John M.; Peake, Janice L.; Plopper, Charles G.; Schelegle, Edward S.; Gershwin, Laurel J.; Pinkerton, Kent E.

    2006-01-01

    Both allergen and ozone exposure increase asthma symptoms and airway responsiveness in children. Little is known about how these inhalants may differentially modify airway responsiveness in large proximal as compared to small distal airways. We evaluated whether bronchi and respiratory bronchioles from infant monkeys exposed episodically to allergen and/or ozone differentially develop intrinsic hyperresponsiveness to methacholine and whether eosinophils and/or pulmonary neuroendocrine cells play a role. Infant monkeys were exposed episodically for 5 months to: (1) filtered air, (2) aerosolized house dust mite allergen, (3) ozone 0.5 ppm, or (4) house dust mite allergen + ozone. Studying the function/structure relationship of the same lung slices, we evaluated methacholine airway responsiveness and histology of bronchi and respiratory bronchioles. In bronchi, intrinsic responsiveness was increased by allergen exposure, an effect reduced by bombesin antagonist. In respiratory bronchioles, intrinsic airway responsiveness was increased by allergen + ozone exposure. Eosinophils were increased by allergen and allergen + ozone exposure in bronchi and by allergen exposure in respiratory bronchioles. In both airways, exposure to allergen + ozone resulted in fewer tissue eosinophils than did allergen exposure alone. In bronchi, but not in respiratory bronchioles, the number of eosinophils and neuroendocrine cells correlated with airway responsiveness. We conclude that episodically exposing infant monkeys to house dust mite allergen with or without ozone increased intrinsic airway responsiveness to methacholine in bronchi differently than in respiratory bronchioles. In bronchi, eosinophils and neuroendocrine cells may play a role in the development of airway hyperresponsiveness

  17. TOMS/Nimbus-7 Total Column Ozone Daily L3 Global 1x1.25 deg Lat/Lon Grid V008

    Data.gov (United States)

    National Aeronautics and Space Administration — This data product contains TOMS/Nimbus-7 Total Column Ozone Daily L3 Global 1x1.25 deg Lat/Lon Grid Version 8 data in ASCII format. The Total Ozone Mapping...

  18. Modelling of individual subject ozone exposure response kinetics.

    Science.gov (United States)

    Schelegle, Edward S; Adams, William C; Walby, William F; Marion, M Susan

    2012-06-01

    A better understanding of individual subject ozone (O(3)) exposure response kinetics will provide insight into how to improve models used in the risk assessment of ambient ozone exposure. To develop a simple two compartment exposure-response model that describes individual subject decrements in forced expiratory volume in one second (FEV(1)) induced by the acute inhalation of O(3) lasting up to 8 h. FEV(1) measurements of 220 subjects who participated in 14 previously completed studies were fit to the model using both particle swarm and nonlinear least squares optimization techniques to identify three subject-specific coefficients producing minimum "global" and local errors, respectively. Observed and predicted decrements in FEV(1) of the 220 subjects were used for validation of the model. Further validation was provided by comparing the observed O(3)-induced FEV(1) decrements in an additional eight studies with predicted values obtained using model coefficients estimated from the 220 subjects used in cross validation. Overall the individual subject measured and modeled FEV(1) decrements were highly correlated (mean R(2) of 0.69 ± 0.24). In addition, it was shown that a matrix of individual subject model coefficients can be used to predict the mean and variance of group decrements in FEV(1). This modeling approach provides insight into individual subject O(3) exposure response kinetics and provides a potential starting point for improving the risk assessment of environmental O(3) exposure.

  19. Climate change, ozone depletion and the impact on ultraviolet exposure of human skin

    International Nuclear Information System (INIS)

    Diffey, Brian

    2004-01-01

    For 30 years there has been concern that anthropogenic damage to the Earth's stratospheric ozone layer will lead to an increase of solar ultraviolet (UV) radiation reaching the Earth's surface, with a consequent adverse impact on human health, especially to the skin. More recently, there has been an increased awareness of the interactions between ozone depletion and climate change (global warming), which could also impact on human exposure to terrestrial UV. The most serious effect of changing UV exposure of human skin is the potential rise in incidence of skin cancers. Risk estimates of this disease associated with ozone depletion suggest that an additional peak incidence of 5000 cases of skin cancer per year in the UK would occur around the mid-part of this century. Climate change, which is predicted to lead to an increased frequency of extreme temperature events and high summer temperatures, will become more frequent in the UK. This could impact on human UV exposure by encouraging people to spend more time in the sun. Whilst future social trends remain uncertain, it is likely that over this century behaviour associated with climate change, rather than ozone depletion, will be the largest determinant of sun exposure, and consequent impact on skin cancer, of the UK population. (topical review)

  20. Prolonged ozone exposure in an allergic airway disease model: Adaptation of airway responsiveness and airway remodeling

    Directory of Open Access Journals (Sweden)

    Park Chang-Soo

    2006-02-01

    Full Text Available Abstract Background Short-term exposure to high concentrations of ozone has been shown to increase airway hyper-responsiveness (AHR. Because the changes in AHR and airway inflammation and structure after chronic ozone exposure need to be determined, the goal of this study was to investigate these effects in a murine model of allergic airway disease. Methods We exposed BALB/c mice to 2 ppm ozone for 4, 8, and 12 weeks. We measured the enhanced pause (Penh to methacholine and performed cell differentials in bronchoalveolar lavage fluid. We quantified the levels of IL-4 and IFN-γ in the supernatants of the bronchoalveolar lavage fluids using enzyme immunoassays, and examined the airway architecture under light and electron microscopy. Results The groups exposed to ozone for 4, 8, and 12 weeks demonstrated decreased Penh at methacholine concentrations of 12.5, 25, and 50 mg/ml, with a dose-response curve to the right of that for the filtered-air group. Neutrophils and eosinophils increased in the group exposed to ozone for 4 weeks compared to those in the filtered-air group. The ratio of IL-4 to INF-γ increased significantly after exposure to ozone for 8 and 12 weeks compared to the ratio for the filtered-air group. The numbers of goblet cells, myofibroblasts, and smooth muscle cells showed time-dependent increases in lung tissue sections from the groups exposed to ozone for 4, 8, and 12 weeks. Conclusion These findings demonstrate that the increase in AHR associated with the allergic airway does not persist during chronic ozone exposure, indicating that airway remodeling and adaptation following repeated exposure to air pollutants can provide protection against AHR.

  1. PLASMA AND LUNG MACROPHAGE CAROTENOID RESPONSIVENESS TO SUPPLEMENTATION AND OZONE EXPOSURE IN HUMANS

    Science.gov (United States)

    OBJECTIVE:: To examine the effect of ozone exposure and vegetable juice supplementation on plasma and lung macrophage concentrations of carotenoids. DESIGN:: A randomized trial. SETTING:: Subjects were exposed to ambient air prior to antioxidant supplementation and to ozone after...

  2. Reconstruction of daily erythemal UV radiation values for the last century - The benefit of modelled ozone

    Science.gov (United States)

    Junk, J.; Feister, U.; Rozanov, E.; Krzyścin, J. W.

    2013-05-01

    Solar erythemal UV radiation (UVER) is highly relevant for numerous biological processes that affect plants, animals, and human health. Nevertheless, long-term UVER records are scarce. As significant declines in the column ozone concentration were observed in the past and a recovery of the stratospheric ozone layer is anticipated by the middle of the 21st century, there is a strong interest in the temporal variation of UVER time series. Therefore, we combined groundbased measurements of different meteorological variables with modeled ozone data sets to reconstruct time series of daily totals of UVER at the Meteorological Observatory Potsdam, Germany. Artificial neural networks were trained with measured UVER, sunshine duration, the day of year, measured and modeled total column ozone, as well as the minimum solar zenith angle. This allows for the reconstruction of daily totals of UVER for the period from 1901 to 1999. Additionally, analyses of the long-term variations from 1901 until 1999 of the reconstructed, new UVER data set are presented. The time series of monthly and annual totals of UVER provide a long-term meteorological basis for epidemiological investigations in human health and occupational medicine for the region of Potsdam and Berlin. A strong benefit of our ANN-approach is the fact that it can be easily adapted to different geographical locations, as successfully tested in the framework of the COSTAction 726.

  3. Effect of 3 years' free-air exposure to elevated ozone on mature Norway spruce (Picea abies (L.) Karst.) needle epicuticular wax physicochemical characteristics

    International Nuclear Information System (INIS)

    Percy, Kevin E.; Manninen, Sirkku; Haeberle, Karl-Heinz; Heerdt, C.; Werner, H.; Henderson, Gary W.; Matyssek, Rainer

    2009-01-01

    We examined the effect of ozone (O 3 ) on Norway spruce (Picea abies) needle epicuticular wax over three seasons at the Kranzberg Ozone Fumigation Experiment. Exposure to 2x ambient O 3 ranged from 64.5 to 74.2 μl O 3 l -1 h AOT40, and 117.1 to 123.2 nl O 3 l -1 4th highest daily maximum 8-h average O 3 concentration. The proportion of current-year needle surface covered by wax tubes, tube aggregates, and plates decreased (P = 0.011) under 2x O 3 . Epistomatal chambers had increased deposits of amorphous wax. Proportion of secondary alcohols varied due to year (P = 0.004) and O 3 treatment (P = 0.029). Secondary alcohols were reduced by 9.1% under 2x O 3 . Exposure to 2x O 3 increased (P = 0.037) proportions of fatty acids by 29%. Opposing trends in secondary alcohols and fatty acids indicate a direct action of O 3 on wax biosynthesis. These results demonstrate O 3 -induced changes in biologically important needle surface characteristics of 50-year-old field-grown trees. - Free-air ozone exposure induced changes in needle wax characteristics of mature Picea abies.

  4. Toward an ozone standard to protect vegetation based on effective dose: a review of deposition resistances and a possible metric

    Science.gov (United States)

    Massman, W. J.

    Present air quality standards to protect vegetation from ozone are based on measured concentrations (i.e., exposure) rather than on plant uptake rates (or dose). Some familiar cumulative exposure-based indices include SUM06, AOT40, and W126. However, plant injury is more closely related to dose, or more appropriately to effective dose, than to exposure. This study develops and applies a simple model for estimating effective ozone dose that combines the plant canopy's rate of stomatal ozone uptake with the plant's defense to ozone uptake. Here the plant defense is explicitly parameterized as a function of gross photosynthesis and the model is applied using eddy covariance (ozone and CO 2) flux data obtained at a vineyard site in the San Joaquin Valley during the California Ozone Deposition Experiment (CODE91). With the ultimate intention of applying these concepts using prognostic models and remotely sensed data, the pathways for ozone deposition are parameterized (as much as possible) in terms of canopy LAI and the surface friction velocity. Results indicate that (1) the daily maximum potential for plant injury (based on effective dose) tends to coincide with the daily peak in ozone mixing ratio (ppbV), (2) potentially there are some significant differences between ozone metrics based on dose (no plant defense) and effective dose, and (3) nocturnal conductance can contribute significantly to the potential for plant ozone injury.

  5. TOWARDS RELIABLE AND COST-EFFECTIVE OZONE EXPOSURE ASSESSMENT: PARAMETER EVALUATION AND MODEL VALIDATION USING THE HARVARD SOUTHERN CALIFORNIA CHRONIC OZONE EXPOSURE STUDY DATA

    Science.gov (United States)

    Accurate assessment of chronic human exposure to atmospheric criteria pollutants, such as ozone, is critical for understanding human health risks associated with living in environments with elevated ambient pollutant concentrations. In this study, we analyzed a data set from a...

  6. Does the acute pulmonary response to ozone depend on the cumulative exposure?

    International Nuclear Information System (INIS)

    Anon.

    2008-01-01

    In experimental conditions, repeated ozone exposure induces adaptive phenomena that attenuate lung function and inflammatory responses. But this study did not find that lifetime cumulative exposure had a protective effect; indeed, it found the contrary. (author)

  7. Linear and regressive stochastic models for prediction of daily maximum ozone values at Mexico City atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Bravo, J. L [Instituto de Geofisica, UNAM, Mexico, D.F. (Mexico); Nava, M. M [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico); Gay, C [Centro de Ciencias de la Atmosfera, UNAM, Mexico, D.F. (Mexico)

    2001-07-01

    We developed a procedure to forecast, with 2 or 3 hours, the daily maximum of surface ozone concentrations. It involves the adjustment of Autoregressive Integrated and Moving Average (ARIMA) models to daily ozone maximum concentrations at 10 monitoring atmospheric stations in Mexico City during one-year period. A one-day forecast is made and it is adjusted with the meteorological and solar radiation information acquired during the first 3 hours before the occurrence of the maximum value. The relative importance for forecasting of the history of the process and of meteorological conditions is evaluated. Finally an estimate of the daily probability of exceeding a given ozone level is made. [Spanish] Se aplica un procedimiento basado en la metodologia conocida como ARIMA, para predecir, con 2 o 3 horas de anticipacion, el valor maximo de la concentracion diaria de ozono. Esta basado en el calculo de autorregresiones y promedios moviles aplicados a los valores maximos de ozono superficial provenientes de 10 estaciones de monitoreo atmosferico en la Ciudad de Mexico y obtenidos durante un ano de muestreo. El pronostico para un dia se ajusta con la informacion meteorologica y de radiacion solar correspondiente a un periodo que antecede con al menos tres horas la ocurrencia esperada del valor maximo. Se compara la importancia relativa de la historia del proceso y de las condiciones meteorologicas previas para el pronostico. Finalmente se estima la probabilidad diaria de que un nivel normativo o preestablecido para contingencias de ozono sea rebasado.

  8. The effect of ozone exposure on the airway response to inhaled allergens; Die Wirkung der Einatmung von Ozon auf die allergische Reaktion des Bronchialsystems

    Energy Technology Data Exchange (ETDEWEB)

    Joerres, R. [Krankenhaus Grosshansdorf (Germany). Zentrum fuer Pneumologie und Thoraxchirurgie; Nowak, D. [Krankenhaus Grosshansdorf (Germany). Zentrum fuer Pneumologie und Thoraxchirurgie; Magnussen, H. [Krankenhaus Grosshansdorf (Germany). Zentrum fuer Pneumologie und Thoraxchirurgie

    1995-06-01

    The aim of our study was to determine whether a short-term exposure to ozone enhances the bronchial response to allergens in subjects with allergic asthma, or facilitates a bronchial response in subjects with allergic rhinitis. In the first part of the study we investigated 57 subjects with mild stable asthma, 29 subjects with allergic rhinitis only and 32 healthy subjects. They were exposed to 250 ppb ozone for 3 hrs of intermittent exercise. The effects of ozone on symptoms, lung function parameters and methacholine responsiveness were no markedly different between groups. Twenty-four subjects with asthma and a proven bronchial response to an inhaled allergen, 12 subjects with allergic rhinitis and 10 healthy subjects participated in the second part of the study. In randomized order, subjects breathed 250 ppb ozone or filtered air (FA) for 3 hrs of intermittent exercise. Lung function and airway responsiveness to methacholine were determined before and after exposures, and allergen inhalation challenges were performed 3 hrs after exposures. The 5 subjects with asthma showed increased airway responsiveness to the inhaled allergen after ozone. The subjects with rhinitis showed a slight bronchial response when a high dose of allergen was inhalated after ozone exposure. The changes in lung function, methacholine and allergen responsiveness induced by ozone did not correlate with each other. Our data suggest that a short-term exposure to ozone can increase bronchial allergen responsiveness in subjects with asymptomatic to mild asthma and that this effect is not directly related to other functional changes induced by ozone. (orig./MG) [Deutsch] Unsere Untersuchung widmete sich der Frage, ob die Einatmung von Ozon das Auftreten oder die Auspraegung einer allergischen Reaktion der Atemwege beeinflussen kann. Zunaechst prueften wir 57 Probanden mit allergischem Asthma bronchiale, 29 mit allergischer Rhinitis ohne Asthma und 32 gesunde Kontrollpersonen auf die

  9. MODIS/Terra Aerosol Cloud Water Vapor Ozone Daily L3 Global 1Deg CMG V006

    Data.gov (United States)

    National Aeronautics and Space Administration — MODIS/Terra Aerosol Cloud Water Vapor Ozone Daily L3 Global 1Deg CMG (MOD08_D3). MODIS was launched aboard the Terra satellite on December 18, 1999 (10:30 am equator...

  10. MODIS/Aqua Aerosol Cloud Water Vapor Ozone Daily L3 Global 1Deg CMG V006

    Data.gov (United States)

    National Aeronautics and Space Administration — MODIS/Aqua Aerosol Cloud Water Vapor Ozone Daily L3 Global 1Deg CMG (MYD08_D3). MODIS was launched aboard the Aqua satellite on May 04, 2002 (1:30 pm equator...

  11. Effect of 3 years' free-air exposure to elevated ozone on mature Norway spruce (Picea abies (L.) Karst.) needle epicuticular wax physicochemical characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Percy, Kevin E., E-mail: kpercy@nbnet.nb.c [Natural Resources Canada, Canadian Forest Service-Atlantic Forestry Centre, 1350 Regent Street, Fredericton, NB, E3B 5P7 (Canada); Manninen, Sirkku [Department of Biological and Environmental Sciences, P.O. Box 56, University of Helsinki, 00014 Helsinki (Finland); Department of Biology, P.O. Box 3000, University of Oulu, 90014 Oulu (Finland); Haeberle, Karl-Heinz [Ecophysiology of Plants, Department of Ecology, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Heerdt, C.; Werner, H. [Ecoclimatology, Department of Ecology, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Henderson, Gary W. [Natural Resources Canada, Canadian Forest Service-Atlantic Forestry Centre, 1350 Regent Street, Fredericton, NB, E3B 5P7 (Canada); Matyssek, Rainer [Ecophysiology of Plants, Department of Ecology, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany)

    2009-05-15

    We examined the effect of ozone (O{sub 3}) on Norway spruce (Picea abies) needle epicuticular wax over three seasons at the Kranzberg Ozone Fumigation Experiment. Exposure to 2x ambient O{sub 3} ranged from 64.5 to 74.2 mul O{sub 3} l{sup -1} h AOT40, and 117.1 to 123.2 nl O{sub 3} l{sup -1} 4th highest daily maximum 8-h average O{sub 3} concentration. The proportion of current-year needle surface covered by wax tubes, tube aggregates, and plates decreased (P = 0.011) under 2x O{sub 3}. Epistomatal chambers had increased deposits of amorphous wax. Proportion of secondary alcohols varied due to year (P = 0.004) and O{sub 3} treatment (P = 0.029). Secondary alcohols were reduced by 9.1% under 2x O{sub 3}. Exposure to 2x O{sub 3} increased (P = 0.037) proportions of fatty acids by 29%. Opposing trends in secondary alcohols and fatty acids indicate a direct action of O{sub 3} on wax biosynthesis. These results demonstrate O{sub 3}-induced changes in biologically important needle surface characteristics of 50-year-old field-grown trees. - Free-air ozone exposure induced changes in needle wax characteristics of mature Picea abies.

  12. TOMS/Earth-Probe Total Ozone Aerosol Index UV-Reflectivity UV-B Erythemal Irradiance Daily L3 Global 1x1.25 deg V008

    Data.gov (United States)

    National Aeronautics and Space Administration — The Total Ozone Mapping Spectrometer (TOMS) version 8 daily global gridded data consist of total column ozone, aerosol index, Lambertian effective surface...

  13. Photochemical oxidants injury in rice plants. III. Effect of ozone on physiological activities in rice plants

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, H; Saka, H

    1978-01-01

    Experiments were made to determine the effect of photochemical oxidants on physiological activities of rice plants. Rice plants were fumigated with ozone at concentrations of 0.12-0.20 ppm for 2-3 hr to investigate acute injury and at 0.05 and 0.09 ppm for daily exposure from 3.0 leaf stage to assess the effect of ozone on growth. It was observed that malondialdehyde produced by disruption of the components of the membrane increased in the leaves exposed to ozone. Ozone reduced the RuBP-carboxylase activity in both young and old leaves 12-24 hr after fumigation. In the young leaves the activity of this enzyme recovered to some extent after 48 hr, but it did not show any recovery in the old leaves. On the other hand, ozone remarkably increased the peroxidase activity and slightly increased acid phosphatase in all leaves. Abnormally high ethylene evolution and oxygen uptake were detected in leaves soon after ozone fumigation. In general, high molecular protein and chlorophyll contents in the detached leaves decreased with incubation in dark, particularly in the old ones. These phenomena were more accelerated by ozone fumigation. Kinetin and benzimidazole showed significant effects on chlorophyll retention in ozone-exposed leaves. Reduction of plant growth and photosynthetic rate was recognized even in low concentration of ozone in daily exposure at 0.05 and 0.09 ppm. From these results it was postulated that ozone may cause the senescence of leaves in rice plants.

  14. Scientific information and public opinion. Daily press analysis about ozone hole in the years 1996-1997

    International Nuclear Information System (INIS)

    Bertuzzi, D.; Borrelli, G.

    1999-01-01

    One of ENEA's many activities consists in dealing with the analysis of information strategies. In this case the analysis concerns an environmental issue, the ozone hole which, in spite of the consideration given by the media, is not sufficiently highlighted, as well as in the case of climate changes issue. A survey of the coverage of four daily newspapers was realized; the time period covered by the analysis spans form January 1996 to December 1997, 77 articles in total. The newspapers involved are: La Repubblica, Il Corriere della Sera, L'Unita' on a national scale, and Il Resto del Carlino on a regional scale. The number of articles analyzed is divided as follows: 26 for the Repubblica, 24 for the Corriere della Sera, 21 for the Unita', 6 for the Resto del Carlino. The purpose of the work was to detect quality and quantity indicators of the Italian press about the ozone hole issue and possible environmental risks conveyed to the public, using the classical methods of the Content analysis. The analysis, carried out through a questionnaire realized for another research on climate change and daily press and appropriately readapted, consisted of 35 questions pointing out the fundamental characteristics of each article: (i) morphological characteristics; (ii) modalities describing the ozone hole; (iii) communication connotations [it

  15. Increased CCL24/eotaxin-2 with postnatal ozone exposure in allergen-sensitized infant monkeys is not associated with recruitment of eosinophils to airway mucosa

    International Nuclear Information System (INIS)

    Chou, Debbie L.; Gerriets, Joan E.; Schelegle, Edward S.; Hyde, Dallas M.; Miller, Lisa A.

    2011-01-01

    Epidemiology supports a causal link between air pollutant exposure and childhood asthma, but the mechanisms are unknown. We have previously reported that ozone exposure can alter the anatomic distribution of CD25+ lymphocytes in airways of allergen-sensitized infant rhesus monkeys. Here, we hypothesized that ozone may also affect eosinophil trafficking to allergen-sensitized infant airways. To test this hypothesis, we measured blood, lavage, and airway mucosa eosinophils in 3-month old monkeys following cyclical ozone and house dust mite (HDM) aerosol exposures. We also determined if eotaxin family members (CCL11, CCL24, CCL26) are associated with eosinophil location in response to exposures. In lavage, eosinophil numbers increased in animals exposed to ozone and/or HDM. Ozone + HDM animals showed significantly increased CCL24 and CCL26 protein in lavage, but the concentration of CCL11, CCL24, and CCL26 was independent of eosinophil number for all exposure groups. In airway mucosa, eosinophils increased with exposure to HDM alone; comparatively, ozone and ozone + HDM resulted in reduced eosinophils. CCL26 mRNA and immunofluorescence staining increased in airway mucosa of HDM alone animals and correlated with eosinophil volume. In ozone + HDM animal groups, CCL24 mRNA and immunofluorescence increased along with CCR3 mRNA, but did not correlate with airway mucosa eosinophils. Cumulatively, our data indicate that ozone exposure results in a profile of airway eosinophil migration that is distinct from HDM mediated pathways. CCL24 was found to be induced only by combined ozone and HDM exposure, however expression was not associated with the presence of eosinophils within the airway mucosa. -- Highlights: ► Ozone can modulate the localization of eosinophils in infant allergic airways. ► Expression of eotaxins within the lung is affected by ozone and allergen exposure. ► CCL24 induction by ozone and allergen exposure is not linked to eosinophilia.

  16. Effect of Gaseous Ozone Exposure on the Bacteria Counts and Oxidative Properties of Ground Hanwoo Beef at Refrigeration Temperature.

    Science.gov (United States)

    Cho, Youngjae; Muhlisin; Choi, Ji Hye; Hahn, Tae-Wook; Lee, Sung Ki

    2014-01-01

    This study was designed to elucidate the effect of ozone exposure on the bacteria counts and oxidative properties of ground Hanwoo beef contaminated with Escherichia coli O157:H7 at refrigeration temperature. Ground beef was inoculated with 7 Log CFU/g of E. coli O157:H7 isolated from domestic pigs and was then subjected to ozone exposure (10×10(-6) kg O3 h(-1)) at 4℃ for 3 d. E. coli O157:H7, total aerobic and anaerobic bacterial growth and oxidative properties including instrumental color changes, TBARS, catalase (CAT) and glutathione peroxidase (GPx) activity were evaluated. Ozone exposure significantly prohibited (pgenerator inside a refrigerator. Further studies regarding the ozone concentrations and exposure times are needed.

  17. Differential expression of ozone-induced gene during exposures to ...

    African Journals Online (AJOL)

    Differential expression of ozone-induced gene during exposures to salt stress in Polygonum sibiricum Laxm leaves, stem and underground stem. ... PcOZI-1 mRNA in untreated plants was detected at low levels in underground stem, leaves and at higher levels in stem. PcOZI-1 mRNA accumulation was transiently induced ...

  18. Ozone air pollution and foliar injury development on native plants of Switzerland

    International Nuclear Information System (INIS)

    Novak, Kristopher; Skelly, John M.; Schaub, Marcus; Kraeuchi, Norbert; Hug, Christian; Landolt, Werner; Bleuler, Peter

    2003-01-01

    Visible ozone-induced foliar injury on native forest species of Switzerland was identified and confirmed under ambient OTC-conditions and related to the current European AOT40 standard. - The objectives of this study were to examine the foliar sensitivity to ozone exposure of 12 tree, shrub, and herbaceous species native to southern Switzerland and determine the seasonal cumulative ozone exposures required to induce visible foliar injury. The study was conducted from the beginning of May through the end of August during 2000 and 2001 using an open-top chamber research facility located within the Lattecaldo Cantonal Forest Nursery in Canton Ticino, southern Switzerland (600 m asl). Plants were examined daily and dates of initial foliar injury were recorded in order to determine the cumulative AOT40 ppb h ozone exposure required to cause visible foliar injury. Plant responses to ozone varied significantly among species; 11 species exhibited visible symptoms typical of exposures to ambient ozone. The symptomatic species (from most to least sensitive) were Populus nigra, Viburnum lantana, Salix alba, Crataegus monogyna, Viburnum opulus, Tilia platyphyllos, Cornus alba, Prunus avium, Fraxinus excelsior, Ribes alpinum, and Tilia cordata; Clematis spp. did not show foliar symptoms. Of the 11 symptomatic species, five showed initial injury below the critical level AOT40 10 ppmh O 3 in the 2001 season

  19. Effects and mechanism on Kapton film under ozone exposure in a ground near space simulator

    Science.gov (United States)

    Wei, Qiang; Yang, Guimin; Liu, Gang; Jiang, Haifu; Zhang, Tingting

    2018-05-01

    The effect on aircraft materials in the near space environment is a key part of air-and-space integration research. Ozone and aerodynamic fluids are important organizational factors in the near space environment and both have significant influences on the performance of aircraft materials. In the present paper a simulated ozone environment was used to test polyimide material that was rotated at the approximate velocity of 150-250 m/s to form an aerodynamic fluid field. The goal was to evaluate the performance evolution of materials under a comprehensive environment of ozone molecular corrosion and aerodynamic fluids. The research results show that corrosion and sputtering by ozone molecules results in Kapton films exhibiting a rugged "carpet-like" morphology exhibits an increase in surface roughness. The morphology after ozone exposure led to higher surface roughness and an increase in surface optical diffuse reflection, which is expressed by the lower optical transmittance and the gradual transition from light orange to brown. The mass loss test, XPS, and FTIR analysis show that the molecular chains on the surface of the Kapton film are destroyed resulting in Csbnd C bond breaking to form small volatile molecules such as CO2 or CO, which are responsible for a linear increase in mass loss per unit area. The Csbnd N and Csbnd O structures exhibit weakening tendency under ozone exposure. The present paper explores the evaluation method for Kapton's adaptability under the ozone exposure test in the near space environment, and elucidates the corrosion mechanism and damage mode of the polyimide material under the combined action of ozone corrosion and the aerodynamic fluid. This work provides a methodology for studying materials in the near-space environment.

  20. Temporal and Spatial Variation in, and Population Exposure to, Summertime Ground-Level Ozone in Beijing.

    Science.gov (United States)

    Zhao, Hui; Zheng, Youfei; Li, Ting; Wei, Li; Guan, Qing

    2018-03-29

    Ground-level ozone pollution in Beijing has been causing concern among the public due to the risks posed to human health. This study analyzed the temporal and spatial distribution of, and investigated population exposure to, ground-level ozone. We analyzed hourly ground-level ozone data from 35 ambient air quality monitoring sites, including urban, suburban, background, and traffic monitoring sites, during the summer in Beijing from 2014 to 2017. The results showed that the four-year mean ozone concentrations for urban, suburban, background, and traffic monitoring sites were 95.1, 99.8, 95.9, and 74.2 μg/m³, respectively. A total of 44, 43, 45, and 43 days exceeded the Chinese National Ambient Air Quality Standards (NAAQS) threshold for ground-level ozone in 2014, 2015, 2016, and 2017, respectively. The mean ozone concentration was higher in suburban sites than in urban sites, and the traffic monitoring sites had the lowest concentration. The diurnal variation in ground-level ozone concentration at the four types of monitoring sites displayed a single-peak curve. The peak and valley values occurred at 3:00-4:00 p.m. and 7:00 a.m., respectively. Spatially, ground-level ozone concentrations decreased in gradient from the north to the south. Population exposure levels were calculated based on ground-level ozone concentrations and population data. Approximately 50.38%, 44.85%, and 48.49% of the total population of Beijing were exposed to ground-level ozone concentrations exceeding the Chinese NAAQS threshold in 2014, 2015, and 2016, respectively.

  1. Temporal and Spatial Variation in, and Population Exposure to, Summertime Ground-Level Ozone in Beijing

    Science.gov (United States)

    Zheng, Youfei; Li, Ting; Wei, Li; Guan, Qing

    2018-01-01

    Ground-level ozone pollution in Beijing has been causing concern among the public due to the risks posed to human health. This study analyzed the temporal and spatial distribution of, and investigated population exposure to, ground-level ozone. We analyzed hourly ground-level ozone data from 35 ambient air quality monitoring sites, including urban, suburban, background, and traffic monitoring sites, during the summer in Beijing from 2014 to 2017. The results showed that the four-year mean ozone concentrations for urban, suburban, background, and traffic monitoring sites were 95.1, 99.8, 95.9, and 74.2 μg/m3, respectively. A total of 44, 43, 45, and 43 days exceeded the Chinese National Ambient Air Quality Standards (NAAQS) threshold for ground-level ozone in 2014, 2015, 2016, and 2017, respectively. The mean ozone concentration was higher in suburban sites than in urban sites, and the traffic monitoring sites had the lowest concentration. The diurnal variation in ground-level ozone concentration at the four types of monitoring sites displayed a single-peak curve. The peak and valley values occurred at 3:00–4:00 p.m. and 7:00 a.m., respectively. Spatially, ground-level ozone concentrations decreased in gradient from the north to the south. Population exposure levels were calculated based on ground-level ozone concentrations and population data. Approximately 50.38%, 44.85%, and 48.49% of the total population of Beijing were exposed to ground-level ozone concentrations exceeding the Chinese NAAQS threshold in 2014, 2015, and 2016, respectively. PMID:29596366

  2. Temporal and Spatial Variation in, and Population Exposure to, Summertime Ground-Level Ozone in Beijing

    Directory of Open Access Journals (Sweden)

    Hui Zhao

    2018-03-01

    Full Text Available Ground-level ozone pollution in Beijing has been causing concern among the public due to the risks posed to human health. This study analyzed the temporal and spatial distribution of, and investigated population exposure to, ground-level ozone. We analyzed hourly ground-level ozone data from 35 ambient air quality monitoring sites, including urban, suburban, background, and traffic monitoring sites, during the summer in Beijing from 2014 to 2017. The results showed that the four-year mean ozone concentrations for urban, suburban, background, and traffic monitoring sites were 95.1, 99.8, 95.9, and 74.2 μg/m3, respectively. A total of 44, 43, 45, and 43 days exceeded the Chinese National Ambient Air Quality Standards (NAAQS threshold for ground-level ozone in 2014, 2015, 2016, and 2017, respectively. The mean ozone concentration was higher in suburban sites than in urban sites, and the traffic monitoring sites had the lowest concentration. The diurnal variation in ground-level ozone concentration at the four types of monitoring sites displayed a single-peak curve. The peak and valley values occurred at 3:00–4:00 p.m. and 7:00 a.m., respectively. Spatially, ground-level ozone concentrations decreased in gradient from the north to the south. Population exposure levels were calculated based on ground-level ozone concentrations and population data. Approximately 50.38%, 44.85%, and 48.49% of the total population of Beijing were exposed to ground-level ozone concentrations exceeding the Chinese NAAQS threshold in 2014, 2015, and 2016, respectively.

  3. Accuracy and practicality of a portable ozone monitor for personal exposure estimates

    Science.gov (United States)

    Sagona, Jessica A.; Weisel, Clifford P.; Meng, Qingyu

    2018-02-01

    Accurate measurements of personal exposure to atmospheric pollutants such as ozone are important for understanding health risks. We tested a new personal ozone monitor (POM; 2B Technologies) for accuracy, precision, and ease of use. The POM's measurements were compared to simultaneous ozone measurements from a 2B Model 205 monitor and a ThermoScientific 49i monitor, and multiple POMs were placed side-by-side to check precision. Tests were undertaken in a controlled environmental facility, outdoors, and in a private residence. Additionally, ten volunteers wore a POM for five days and answered a questionnaire about its ease of use. The POM measured ozone accurately compared to the 49i ozone monitor, with average relative differences of less than 8%. In the controlled environment tests, the POM's ozone measurements did not change in the presence of additional atmospheric constituents with similar absorption lines to ozone, though there may have been a small decrease in precision and accuracy. Precision between POMs varied by environment (r2 = 0.98 outdoors; r2 = 0.3 to 0.9 in controlled lab conditions). Volunteers reported that the POM was reasonably comfortable to wear, although all reported that they felt that it was too noisy. Overall, the POM is a viable option for personal ozone monitoring.

  4. Increased CCL24/eotaxin-2 with postnatal ozone exposure in allergen-sensitized infant monkeys is not associated with recruitment of eosinophils to airway mucosa

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Debbie L.; Gerriets, Joan E. [California National Primate Research Center, UC Davis, Davis, CA 95616 (United States); Schelegle, Edward S.; Hyde, Dallas M. [California National Primate Research Center, UC Davis, Davis, CA 95616 (United States); Department of Anatomy, Physiology, and Cell Biology, UC Davis School of Veterinary Medicine, Davis, CA 95616 (United States); Miller, Lisa A., E-mail: lmiller@ucdavis.edu [California National Primate Research Center, UC Davis, Davis, CA 95616 (United States); Department of Anatomy, Physiology, and Cell Biology, UC Davis School of Veterinary Medicine, Davis, CA 95616 (United States)

    2011-12-15

    Epidemiology supports a causal link between air pollutant exposure and childhood asthma, but the mechanisms are unknown. We have previously reported that ozone exposure can alter the anatomic distribution of CD25+ lymphocytes in airways of allergen-sensitized infant rhesus monkeys. Here, we hypothesized that ozone may also affect eosinophil trafficking to allergen-sensitized infant airways. To test this hypothesis, we measured blood, lavage, and airway mucosa eosinophils in 3-month old monkeys following cyclical ozone and house dust mite (HDM) aerosol exposures. We also determined if eotaxin family members (CCL11, CCL24, CCL26) are associated with eosinophil location in response to exposures. In lavage, eosinophil numbers increased in animals exposed to ozone and/or HDM. Ozone + HDM animals showed significantly increased CCL24 and CCL26 protein in lavage, but the concentration of CCL11, CCL24, and CCL26 was independent of eosinophil number for all exposure groups. In airway mucosa, eosinophils increased with exposure to HDM alone; comparatively, ozone and ozone + HDM resulted in reduced eosinophils. CCL26 mRNA and immunofluorescence staining increased in airway mucosa of HDM alone animals and correlated with eosinophil volume. In ozone + HDM animal groups, CCL24 mRNA and immunofluorescence increased along with CCR3 mRNA, but did not correlate with airway mucosa eosinophils. Cumulatively, our data indicate that ozone exposure results in a profile of airway eosinophil migration that is distinct from HDM mediated pathways. CCL24 was found to be induced only by combined ozone and HDM exposure, however expression was not associated with the presence of eosinophils within the airway mucosa. -- Highlights: Black-Right-Pointing-Pointer Ozone can modulate the localization of eosinophils in infant allergic airways. Black-Right-Pointing-Pointer Expression of eotaxins within the lung is affected by ozone and allergen exposure. Black-Right-Pointing-Pointer CCL24 induction by

  5. OXIDATIVE STRESS-DEPENDENT ALTERED IMMUNE RESPONSES AND CELL DEATH IN SUBSTANTIA NIGRA AFTER OZONE EXPOSURE IN RAT

    Directory of Open Access Journals (Sweden)

    Selva eRivas - Arancibia

    2015-05-01

    Full Text Available Parkinson’s disease has been associated with the selective loss of neurons in the substantia nigra pars compacta. Increasing evidence suggests that oxidative stress plays a major role. The resulting increase in reactive oxygen species triggers a sequence of events that leads to cell damage, activation of microglia cells and neuroinflammatory responses. Our objective was to study whether chronic exposure to low doses of ozone, which produces oxidative stress itself, induces progressive cell death in conjunction with glial alterations in the substantia nigra. Animals were exposed to an ozone-free air stream (control or to low doses of ozone for 7, 15, 30, 60, or 90 days. Each group underwent 1 spectrophotometric analysis for protein oxidation; 2 western blot testing for microglia reactivity and nuclear factor kappa B expression levels; and 3 immunohistochemistry for cytochrome c, GFAP, Iba-1, NFkB and COX-2. Our results indicate that ozone induces an increase in protein oxidation levels, changes in activated astrocytes and microglia, and cell death. NFkB and cytochrome c showed an increase until 30 days of exposure, while cyclooxygenase 2 in the substantia nigra increased from 7 days up to 90 days of repetitive ozone exposure. These results suggest that oxidative stress caused by ozone exposure induces changes in inflammatory responses and progressive cell death in the substantia nigra in rats, which could also be occurring in Parkinson’s disease.

  6. Incorporation of glucose carbons into rat lung lipids after exposure to 0.6 ppm ozone

    International Nuclear Information System (INIS)

    Bassett, D.J.; Rabinowitz, J.L.

    1985-01-01

    Continuous exposure to low concentrations of ozone has previously been associated with proliferation of lung alveolar type II epithelial cells. In this study, 14 C incorporation into tissue lipids was determined in isolated rat lungs by perfusion with [U- 14 C]glucose, at a time of maximal hyperplasia brought about by 3 days continuous exposure to 0.6 ppm ozone. Ozone exposed lungs exhibited increased rates of glycolytic energy production, indicated by an 89% increase in 3 H 2 O generation on perfusion with [5-3H]glucose. Ozone exposure resulted in enhanced 14 C incorporations into glyceride-glycerol and fatty acid moieties of lung lipids of 95 and 180%, respectively, with a greater proportion of label being recovered in shorter chain fatty acids. Although increased labeling was observed in both neutral and phospholipids, the pattern of 14 C recovery suggested a relative increased glucose carbon incorporation into lung free fatty acids, phosphatidic acid, and such membrane associated lipids as phosphatidylinositol and those containing sphingosine. These results are consistent with the needs of a dividing cell population for enhanced energy production and synthesis of new lipids

  7. In situ autumn ozone fumigation of mature Norway spruce - Effects on net photosynthesis

    DEFF Research Database (Denmark)

    Mikkelsen, Teis Nørgaard; Ro-Poulsen, H.

    2002-01-01

    concentration. The experiment was conducted during 70 days during the autumn. Our system could not detect any ozone effects on dark respiration, but eventually effects on dark respiration could be masked in signal noise. An inhibition of daily net photosynthesis in ozone treated shoots was apparent......, and it is was found that a mean increase in ozone concentration of 10 nl l(-1) reduced net photosynthesis with 7.4 %. This effect should be related to a pre-exposure during the season of AOT40 12.5 mul l(-1) h....

  8. Ozone exposure and pulmonary effects in panel and human clinical studies: Considerations for design and interpretation.

    Science.gov (United States)

    Rohr, Annette C

    2018-04-01

    A wealth of literature exists regarding the pulmonary effects of ozone, a photochemical pollutant produced by the reaction of nitrogen oxide and volatile organic precursors in the presence of sunlight. This paper focuses on epidemiological panel studies and human clinical studies of ozone exposure, and discusses issues specific to this pollutant that may influence study design and interpretation as well as other, broader considerations relevant to ozone-health research. The issues are discussed using examples drawn from the wider literature. The recent panel and clinical literature is also reviewed. Health outcomes considered include lung function, symptoms, and pulmonary inflammation. Issues discussed include adversity, reversibility, adaptation, variability in ozone exposure metric used and health outcomes evaluated, co-pollutants in panel studies, influence of temperature in panel studies, and multiple comparisons. Improvements in and standardization of panel study approaches are recommended to facilitate comparisons between studies as well as meta-analyses. Additional clinical studies at or near the current National Ambient Air Quality Standard (NAAQS) of 70 ppb are recommended, as are clinical studies in sensitive subpopulations such as asthmatics. The pulmonary health impacts of ozone exposure have been well documented using both epidemiological and chamber study designs. However, there are a number of specific methodological and related issues that should be considered when interpreting the results of these studies and planning additional research, including the standardization of exposure and health metrics to facilitate comparisons among studies.

  9. Daily personal exposure to black carbon: A pilot study

    Science.gov (United States)

    Williams, Ryan D.; Knibbs, Luke D.

    2016-05-01

    Continuous personal monitoring is the benchmark for air pollution exposure assessment. Black carbon (BC) is a strong marker of primary combustion like vehicle and biomass emissions. There have been few studies that quantified daily personal BC exposure and the contribution that different microenvironments make to it. In this pilot study, we used a portable aethalometer to measure BC concentrations in an individual's breathing zone at 30-s intervals while he performed his usual daily activities. We used a GPS and time-activity diary to track where he spent his time. We performed twenty 24-h measurements, and observed an arithmetic mean daily exposure concentration of 603 ng/m3. We estimated that changing commute modes from bus to train reduced the 24-h mean BC exposure concentration by 29%. Switching from open windows to closed windows and recirculated air in a car led to a reduction of 32%. Living in a home without a wood-fired heater caused a reduction of 50% compared with a wood-heated home. Our preliminary findings highlight the potential utility of simple approaches to reduce a person's daily BC exposure.

  10. Ozone Exposure Increases Circulating Stress Hormones and Lipid Metabolites in Humans

    Science.gov (United States)

    RATIONALE: Air pollution has been associated with increased prevalence of type 2 diabetes; however, the mechanisms remain unknown. We have shown that acute ozone exposure in rats induces release of stress hormones, hyperglycemia, leptinemia, and gluoose intolerance that are assoc...

  11. Germination of fungal conidia after exposure to low concentration ozone atmospheres.

    Science.gov (United States)

    The germinability of conidia of Alternaria alternata, Aspergillus flavus, Aspergillus niger, Penicillium digitatum, Penicillium expansum, or Penicillium italicum was determined periodically during exposure for approximately 100 days to a humid atmosphere of air alone or air containing 150 ppb ozone ...

  12. Bayesian Hierarchical Distributed Lag Models for Summer Ozone Exposure and Cardio-Respiratory Mortality

    OpenAIRE

    Yi Huang; Francesca Dominici; Michelle Bell

    2004-01-01

    In this paper, we develop Bayesian hierarchical distributed lag models for estimating associations between daily variations in summer ozone levels and daily variations in cardiovascular and respiratory (CVDRESP) mortality counts for 19 U.S. large cities included in the National Morbidity Mortality Air Pollution Study (NMMAPS) for the period 1987 - 1994. At the first stage, we define a semi-parametric distributed lag Poisson regression model to estimate city-specific relative rates of CVDRESP ...

  13. Long-term exposure to ambient ozone and mortality: a quantitative systematic review and meta-analysis of evidence from cohort studies.

    Science.gov (United States)

    Atkinson, R W; Butland, B K; Dimitroulopoulou, C; Heal, M R; Stedman, J R; Carslaw, N; Jarvis, D; Heaviside, C; Vardoulakis, S; Walton, H; Anderson, H R

    2016-02-23

    While there is good evidence for associations between short-term exposure to ozone and a range of adverse health outcomes, the evidence from narrative reviews for long-term exposure is suggestive of associations with respiratory mortality only. We conducted a systematic, quantitative evaluation of the evidence from cohort studies, reporting associations between long-term exposure to ozone and mortality. Cohort studies published in peer-reviewed journals indexed in EMBASE and MEDLINE to September 2015 and PubMed to October 2015 and cited in reviews/key publications were identified via search strings using terms relating to study design, pollutant and health outcome. Study details and estimate information were extracted and used to calculate standardised effect estimates expressed as HRs per 10 ppb increment in long-term ozone concentrations. 14 publications from 8 cohorts presented results for ozone and all-cause and cause-specific mortality. We found no evidence of associations between long-term annual O3 concentrations and the risk of death from all causes, cardiovascular or respiratory diseases, or lung cancer. 4 cohorts assessed ozone concentrations measured during the warm season. Summary HRs for cardiovascular and respiratory causes of death derived from 3 cohorts were 1.01 (95% CI 1.00 to 1.02) and 1.03 (95% CI 1.01 to 1.05) per 10 ppb, respectively. Our quantitative review revealed a paucity of independent studies regarding the associations between long-term exposure to ozone and mortality. The potential impact of climate change and increasing anthropogenic emissions of ozone precursors on ozone levels worldwide suggests further studies of the long-term effects of exposure to high ozone levels are warranted. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  14. AN EVALUATION OF OZONE EXPOSURE METRICS FOR A SEASONALLY DROUGHT STRESSED PONDEROSA PINE ECOSYSTEM. (R826601)

    Science.gov (United States)

    Ozone stress has become an increasingly significant factor in cases of forest decline reported throughout the world. Current metrics to estimate ozone exposure for forest trees are derived from atmospheric concentrations and assume that the forest is physiologically active at ...

  15. Meta-analysis of the association between short-term exposure to ambient ozone and respiratory hospital admissions

    International Nuclear Information System (INIS)

    Ji Meng; Bell, Michelle L; Cohan, Daniel S

    2011-01-01

    Ozone is associated with health impacts including respiratory outcomes; however, results differ across studies. Meta-analysis is an increasingly important approach to synthesizing evidence across studies. We conducted meta-analysis of short-term ozone exposure and respiratory hospitalizations to evaluate variation across studies and explore some of the challenges in meta-analysis. We identified 136 estimates from 96 studies and investigated how estimates differed by age, ozone metric, season, lag, region, disease category, and hospitalization type. Overall results indicate associations between ozone and various kinds of respiratory hospitalizations; however, study characteristics affected risk estimates. Estimates were similar, but higher, for the elderly compared to all ages and for previous day exposure compared to same day exposure. Comparison across studies was hindered by variation in definitions of disease categories, as some (e.g., asthma) were identified through ≥ 3 different sets of ICD codes. Although not all analyses exhibited evidence of publication bias, adjustment for publication bias generally lowered overall estimates. Emergency hospitalizations for total respiratory disease increased by 4.47% (95% interval: 2.48, 6.50%) per 10 ppb 24 h ozone among the elderly without adjustment for publication bias and 2.97% (1.05, 4.94%) with adjustment. Comparison of multi-city study results and meta-analysis based on single-city studies further suggested publication bias.

  16. The Ecophysiology Of A Pinus Ponderosa Ecosystem Exposed To High Tropospheric Ozone: Implications For Stomatal And Non-Stomatal Ozone Fluxes

    Science.gov (United States)

    Fares, S.; McKay, M.; Goldstein, A.

    2008-12-01

    Ecosystems remove ozone from the troposphere through both stomatal and non-stomatal deposition. The portion of ozone taken up through stomata has an oxidative effect causing damage. We used a multi-year dataset to assess the physiological controls over ozone deposition. Environmental parameters, CO2 and ozone fluxes were measured continuously from January 2001 to December 2006 above a ponderosa pine plantation near Blodgett Forest, Georgetown, California. We studied the dynamic of NEE (Net Ecosystem Exchange, -838 g C m-2 yr-1) and water evapotranspiration on an annual and daily basis. These processes are tightly coupled to stomatal aperture which also controlled ozone fluxes. High levels of ozone concentrations (~ 100 ppb) were observed during the spring-summer period, with corresponding high levels of ozone fluxes (~ 30 μmol m-2 h-1). During the summer season, a large portion of the total ozone flux was due to non-stomatal processes, and we propose that a plant physiological control, releasing BVOC (Biogenic Volatile Organic Compounds), is mainly responsible. We analyzed the correlations of common ozone exposure metrics based on accumulation of concentrations (AOT40 and SUM0) with ozone fluxes (total, stomatal and non-stomatal). Stomatal flux showed poorer correlation with ozone concentrations than non-stomatal flux during summer and fall seasons, which largely corresponded to the growing period. We therefore suggest that AOT40 and SUM0 are poor predictors of ozone damage and that a physiologically based metric would be more effective.

  17. Elevated CO{sub 2} and ozone reduce nitrogen acquisition by Pinus halepensis from its mycorrhizal symbiont

    Energy Technology Data Exchange (ETDEWEB)

    Kytoeviita, M.M. [Oulu Univ., Dept. of Biology, Oulu (Finland); Thiec, D. Le [Univ. Henri Poincare-Nancy, Lab. de Biologie Forestiere, Vandoeuvre-les-Nancy (France); Dizengremel, P. [Unite Ecophysiologie Forestiere-Lab. de Pollution Atmospherique, INRA-Centre de Recherches Forestieres, Champenoux (France)

    2001-07-01

    The effects of 700 {mu}mol mol{sup -1} CO{sub 2} and 200 nmol mol{sup -1} ozone on photosynthesis in Pinus halepensis seedlings and on N translocation from its mycorrhizal symbiont, Paxillus involutus, were studied under nutrient-poor conditions. After 79 days of exposure, ozone reduced and elevated CO{sub 2} increased net assimilation rate. However, the effect was dependent on daily accumulated exposure. No statistically significant differences in total plant mass accumulation were observed, although ozone-treated plants tended to be smaller. Changes in atmospheric gas concentrations induced changes in allocation of resources: under elevated ozone, shoots showed high priority over roots and had significantly elevated N concentrations. As a result of different shoot N concentration and net carbon assimilation rates, photosynthetic N use efficiency was significantly increased under elevated CO{sub 2} and decreased under ozone. The differences in photosynthesis were mirrored in the growth of the fungus in symbiosis with the pine seedlings. However, exposure to CO{sub 2} and ozone both reduced the symbiosis-mediated N uptake. The results suggest an increased carbon cost of symbiosis-mediated N uptake under elevated CO{sub 2} while under ozone, plant N acquisition is preferentially shifted towards increased root uptake. (au)

  18. Exposure-plant response of ambient ozone over the tropical Indian region

    Directory of Open Access Journals (Sweden)

    S. Deb Roy

    2009-07-01

    Full Text Available A high resolution regional chemistry-transport model has been used to study the distribution of exposure-plant response index (AOT40, Accumulated exposure Over a Threshold of 40 ppb, expressed as ppb h over the Indian geographical region for the year 2003 as case study. The directives on ozone pollution in ambient air provided by United Nations Economic Commission for Europe (UNECE and World Health Organization (WHO for vegetation protection (AOT40 have been used to assess the air quality. A substantial temporal and spatial variation in AOT40 values has been observed across the Indian region. Large areas of India show ozone values above the AOT40 threshold limit (3000 ppb h for 3 months. Simulated AOT40 values are found to be substantially higher throughout the year over the most fertile Indo-Gangetic plains than the other regions of India, which can have an adverse effect on plants and vegetation in this region. The observed monthly AOT40 values reported from an Indian station, agree reasonably well with model simulated results. There is an underestimation of AOT40 in the model results during the periods of highest ozone concentration from December to March. We find that the simulated AOT40 target values for protection of vegetation is exceeded even in individual months, especially during November to April. Necessary and effective emission reduction strategies are therefore required to be developed in order to curb the surface level ozone pollution to protect the vegetation from further damage in India whose economy is highly dependent on agricultural sector and may influence the global balance.

  19. Early life exposure to allergen and ozone results in altered development in adolescent rhesus macaque lungs

    International Nuclear Information System (INIS)

    Herring, M.J.; Putney, L.F.; St George, J.A.; Avdalovic, M.V.; Schelegle, E.S.; Miller, L.A.; Hyde, D.M.

    2015-01-01

    In rhesus macaques, previous studies have shown that episodic exposure to allergen alone or combined with ozone inhalation during the first 6 months of life results in a condition with many of the hallmarks of asthma. This exposure regimen results in altered development of the distal airways and parenchyma (Avdalovic et al., 2012). We hypothesized that the observed alterations in the lung parenchyma would be permanent following a long-term recovery in filtered air (FA) housing. Forty-eight infant rhesus macaques (30 days old) sensitized to house dust mite (HDM) were treated with two week cycles of FA, house dust mite allergen (HDMA), ozone (O 3 ) or HDMA/ozone (HDMA + O 3 ) for five months. At the end of the five months, six animals from each group were necropsied. The other six animals in each group were allowed to recover in FA for 30 more months at which time they were necropsied. Design-based stereology was used to estimate volumes of lung components, number of alveoli, size of alveoli, distribution of alveolar volumes, interalveolar capillary density. After 30 months of recovery, monkeys exposed to HDMA, in either group, had significantly more alveoli than filtered air. These alveoli also had higher capillary densities as compared with FA controls. These results indicate that early life exposure to HDMA alone or HDMA + O 3 alters the development process in the lung alveoli. - Highlights: • Abnormal lung development after postnatal exposure to ozone and allergen • This remodeling is shown as smaller, more numerous alveoli and narrower airways. • Allergen appears to have more of an effect than ozone during recovery. • These animals also have continued airway hyperresponsiveness (Moore et al. 2014)

  20. Morphological study of the effects of ozone on rat lung. I. Short-term exposure

    International Nuclear Information System (INIS)

    Hiroshima, K.; Kohno, T.; Owada, H.; Hayashi, Y.

    1987-01-01

    In order to determine the effects of ozone on lungs and the course of cell renewal after damage, young male rats were exposed to 3 ppm of ozone for 4 hr. They were killed at 1, 6, 12, and 18 hr and 1, 2, 3, 4, 7, and 14 days after exposure. One hour before the killing, dividing cells were labeled with tritiated thymidine. Type 1 cells of centriacinar location and bronchiolar cells were severely damaged after exposure. Labeling indices of type 2 cells and bronchiolar nonciliated cells increased 1 day after exposure. Hyperplasia of type 2 cells and bronchiolar nonciliated cells was observed 2 and 3 days after exposure. Ciligenesis of bronchiolar ciliated cells occurred 4 days after exposure. Our study shows that injured type 1 cells are repaired by proliferation of type 2 cells and that injured bronchiolar ciliated and Clara cells are repaired by proliferation of bronchiolar nonciliated cells. These undifferentiated cells are probably progenitors of ciliated cells and Clara cells, and some nonciliated cells are in a transitional form between nonciliated and type 2 cells

  1. Vitamin D Synthesis by UV Radiation: the Importance of Ozone Monitoring

    Science.gov (United States)

    Olds, W. J.; Moore, M. R.; Kimlin, M. G.

    2006-12-01

    The majority of humans rely on incidental sun exposure to maintain vitamin D sufficiency. Depending on where thresholds of vitamin D "sufficiency" are defined, it was recently stated that up to one billion people worldwide have suboptimal vitamin D levels (Bouillon, R., University of Leuven). Even in sunny southeast Queensland, the world's skin cancer capital, a 2006 study uncovered deficiency rates of up to 78% (at a threshold of 75 nmol/L of circulating 25-hydroxyvitamin D). Vitamin D regulates calcium absorption and inadequate levels are proven to result in osteomalacia, osteoporosis, rickets, bone pain and general skeletal weakness. Recent evidence also suggests vitamin D plays a preventative role in autoimmune diseases including numerous cancers, diabetes, schizophrenia, coronary heart disease, depression and other disorders. The most promising means of alleviating the worldwide burden of vitamin D deficiency seems to be by increased UV exposure. However, a much more mature understanding of UV exposures encountered in everyday life is required. This understanding is fundamentally founded in geophysics. UV exposures are strongly influenced by season/time of year, time of day, climate, location, pollution, aerosols and, importantly, ozone. In this work, we use computer simulations to obtain daily totals of vitamin D producing UV at numerous latitudes during one year. The ozone concentration is varied from 260 DU to 360 DU to determine the role of ozone variability on the ambient levels of vitamin D UV. Vitamin D synthesis is highly dependent on UVB. In our results, we demonstrate that this has important implications. Namely, vitamin D is strongly affected by ozone variability, since ozone filters UVB more strongly than UVA. Moreover, since erythema (sunburn) can occur at UVA wavelengths, ozone variation will more strongly affect vitamin D synthesis than erythema. Our results highlight that ozone monitoring is essential for understanding appropriate UV exposures

  2. Early life exposure to allergen and ozone results in altered development in adolescent rhesus macaque lungs

    Energy Technology Data Exchange (ETDEWEB)

    Herring, M.J.; Putney, L.F.; St George, J.A. [California National Primate Research Center, Davis, CA (United States); Avdalovic, M.V. [Department of Internal Medicine, Division of Pulmonary and Critical Care, University of California, Davis, CA (United States); Schelegle, E.S.; Miller, L.A. [California National Primate Research Center, Davis, CA (United States); Hyde, D.M., E-mail: dmhyde@ucdavis.edu [California National Primate Research Center, Davis, CA (United States)

    2015-02-15

    In rhesus macaques, previous studies have shown that episodic exposure to allergen alone or combined with ozone inhalation during the first 6 months of life results in a condition with many of the hallmarks of asthma. This exposure regimen results in altered development of the distal airways and parenchyma (Avdalovic et al., 2012). We hypothesized that the observed alterations in the lung parenchyma would be permanent following a long-term recovery in filtered air (FA) housing. Forty-eight infant rhesus macaques (30 days old) sensitized to house dust mite (HDM) were treated with two week cycles of FA, house dust mite allergen (HDMA), ozone (O{sub 3}) or HDMA/ozone (HDMA + O{sub 3}) for five months. At the end of the five months, six animals from each group were necropsied. The other six animals in each group were allowed to recover in FA for 30 more months at which time they were necropsied. Design-based stereology was used to estimate volumes of lung components, number of alveoli, size of alveoli, distribution of alveolar volumes, interalveolar capillary density. After 30 months of recovery, monkeys exposed to HDMA, in either group, had significantly more alveoli than filtered air. These alveoli also had higher capillary densities as compared with FA controls. These results indicate that early life exposure to HDMA alone or HDMA + O{sub 3} alters the development process in the lung alveoli. - Highlights: • Abnormal lung development after postnatal exposure to ozone and allergen • This remodeling is shown as smaller, more numerous alveoli and narrower airways. • Allergen appears to have more of an effect than ozone during recovery. • These animals also have continued airway hyperresponsiveness (Moore et al. 2014)

  3. TOMS/Earth Probe Total Column Ozone Daily L3 Global 1x1.25 deg Lat/Lon Grid V008

    Data.gov (United States)

    National Aeronautics and Space Administration — This data product contains TOMS/Earth Probe Total Column Ozone Daily L3 Global 1x1.25 deg Lat/Lon Grid Version 8 data in ASCII format. (The shortname for this...

  4. Stratospheric ozone changes under solar geoengineering: implications for UV exposure and air quality

    Science.gov (United States)

    Nowack, Peer Johannes; Abraham, Nathan Luke; Braesicke, Peter; Pyle, John Adrian

    2016-03-01

    Various forms of geoengineering have been proposed to counter anthropogenic climate change. Methods which aim to modify the Earth's energy balance by reducing insolation are often subsumed under the term solar radiation management (SRM). Here, we present results of a standard SRM modelling experiment in which the incoming solar irradiance is reduced to offset the global mean warming induced by a quadrupling of atmospheric carbon dioxide. For the first time in an atmosphere-ocean coupled climate model, we include atmospheric composition feedbacks for this experiment. While the SRM scheme considered here could offset greenhouse gas induced global mean surface warming, it leads to important changes in atmospheric composition. We find large stratospheric ozone increases that induce significant reductions in surface UV-B irradiance, which would have implications for vitamin D production. In addition, the higher stratospheric ozone levels lead to decreased ozone photolysis in the troposphere. In combination with lower atmospheric specific humidity under SRM, this results in overall surface ozone concentration increases in the idealized G1 experiment. Both UV-B and surface ozone changes are important for human health. We therefore highlight that both stratospheric and tropospheric ozone changes must be considered in the assessment of any SRM scheme, due to their important roles in regulating UV exposure and air quality.

  5. Characterizing the impact of projected changes in climate and air quality on human exposures to ozone.

    Science.gov (United States)

    Dionisio, Kathie L; Nolte, Christopher G; Spero, Tanya L; Graham, Stephen; Caraway, Nina; Foley, Kristen M; Isaacs, Kristin K

    2017-05-01

    The impact of climate change on human and environmental health is of critical concern. Population exposures to air pollutants both indoors and outdoors are influenced by a wide range of air quality, meteorological, behavioral, and housing-related factors, many of which are also impacted by climate change. An integrated methodology for modeling changes in human exposures to tropospheric ozone (O 3 ) owing to potential future changes in climate and demographics was implemented by linking existing modeling tools for climate, weather, air quality, population distribution, and human exposure. Human exposure results from the Air Pollutants Exposure Model (APEX) for 12 US cities show differences in daily maximum 8-h (DM8H) exposure patterns and levels by sex, age, and city for all scenarios. When climate is held constant and population demographics are varied, minimal difference in O 3 exposures is predicted even with the most extreme demographic change scenario. In contrast, when population is held constant, we see evidence of substantial changes in O 3 exposure for the most extreme change in climate. Similarly, we see increases in the percentage of the population in each city with at least one O 3 exposure exceedance above 60 p.p.b and 70 p.p.b thresholds for future changes in climate. For these climate and population scenarios, the impact of projected changes in climate and air quality on human exposure to O 3 are much larger than the impacts of changing demographics. These results indicate the potential for future changes in O 3 exposure as a result of changes in climate that could impact human health.

  6. γδ T cells are required for pulmonary IL-17A expression after ozone exposure in mice: role of TNFα.

    Directory of Open Access Journals (Sweden)

    Joel A Mathews

    Full Text Available Ozone is an air pollutant that causes pulmonary symptoms. In mice, ozone exposure causes pulmonary injury and increases bronchoalveolar lavage macrophages and neutrophils. We have shown that IL-17A is important in the recruitment of neutrophils after subacute ozone exposure (0.3 ppm for 24-72 h. We hypothesized that γδ T cells are the main producers of IL-17A after subacute ozone. To explore this hypothesis we exposed wildtype mice and mice deficient in γδ T cells (TCRδ-/- to ozone or room air. Ozone-induced increases in BAL macrophages and neutrophils were attenuated in TCRδ-/- mice. Ozone increased the number of γδ T cells in the lungs and increased pulmonary Il17a mRNA expression and the number of IL-17A+ CD45+ cells in the lungs and these effects were abolished in TCRδ-/- mice. Ozone-induced increases in factors downstream of IL-17A signaling, including G-CSF, IL-6, IP-10 and KC were also decreased in TCRδ-/- versus wildtype mice. Neutralization of IL-17A during ozone exposure in wildtype mice mimicked the effects of γδ T cell deficiency. TNFR2 deficiency and etanercept, a TNFα antagonist, also reduced ozone-induced increases in Il17a mRNA, IL-17A+ CD45+ cells and BAL G-CSF as well as BAL neutrophils. TNFR2 deficient mice also had decreased ozone-induced increases in Ccl20, a chemoattractant for IL-17A+ γδ T cells. Il17a mRNA and IL-17A+ γδ T cells were also lower in obese Cpefat versus lean WT mice exposed to subacute ozone, consistent with the reduced neutrophil recruitment observed in the obese mice. Taken together, our data indicate that pulmonary inflammation induced by subacute ozone requires γδ T cells and TNFα-dependent recruitment of IL-17A+ γδ T cells to the lung.

  7. Loblolly pine seedling growth after inoculation with plant growth-promoting rhizobacteria and ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Estes, B.L.; Enebak, S.A.; Chappelka, A.H. [Auburn Univ., Auburn, AL (United States). School of Forestry and Wildlife Sciences

    2004-07-01

    The conifer tree species with the greatest economic importance in south eastern United States plantations is Loblolly pine. Plantations require intensive fertilization, pesticide application, and irrigation. In these cases growth-promoting rhizobacteria are useful in pest control. While it was once thought that ozone in the troposphere was limited to urban areas, it is now known that it is transported far from its place of origin. Ozone is known to impact plant growth negatively. There have been no previous studies on whether growth-promoting rhizobacteria can decrease the negative effects of ozone. In this study seedlings of Loblolly pine were inoculated with either Bacillus subtilis (Ehrenberg) Cohn or Paenibacillus macerans (Schardinger) Ash. These were exposed to controlled amounts of ozone for 8-12 weeks. All plants showed decreased biomass and increased foliar damage compared to plants that were not exposed to ozone. B. subtilis inoculated plants showed less foliar damage than un-inoculated ones and root dimensions were increased. The use of growth-promoting rhizobacteria is not ready for large-scale commercial application in forestry, but this demonstration of the possible beneficial effects on ozone exposure warrants further investigation. 44 refs., 3 tabs., 2 figs.

  8. Atrophic rhinitis and other nasal lesions induced by a 1-month exposure of F344 rats to 0.25 or 0.5 ppm ozone

    International Nuclear Information System (INIS)

    Hotchkiss, J.A.; Harkema, J.R.; Wacnik, P.W.

    1994-01-01

    Ozone, the principal oxidant pollutant of photochemical smog, is a common inhaled toxicant for metropolitan area residents. The effects of acute and chronic ozone exposure on inflammatory cell influx, hyperplasia, and secretory cell metaplasia within the surface epithelium lining rat nasal airways have previously been reported. On the other hand, there is a paucity of data describing the effects of ozone exposure on the subepithelial tissues (i.e., lamina propria and bone) of nasal turbinates. However, recently, a significant decrease in nasal turbinate bone area in rats chronically exposed (20 mo) to 1 ppm ozone was reported. The purpose of the present study was to examine the effects of a 1-mo ozone exposure on subepithelial tissue compartments of maxilloturbinates in the anterior nasal cavity of rats

  9. The missing piece: Valuing averting behavior for children's ozone exposures

    Energy Technology Data Exchange (ETDEWEB)

    Mansfield, Carol; Reed Johnson, F.; Van Houtven, George [Research Triangle Institute, P.O. Box 12194, Research Triangle Park, NC 27709-2194 (United States)

    2006-08-15

    Individuals can reduce their exposure to air pollution by reducing the amount of time they spend outdoors. Reducing outdoor time is an example of an averting behavior that should be measured as part of willingness to pay (WTP) for improvements in air quality. In this paper, we estimate parents' WTP to prevent restrictions on a child's outdoor time from a stated-preference (SP) conjoint survey. We combine this WTP measure with an estimate of reductions in time spent outdoors on high-ozone days from an activity-diary study to estimate this averting behavior component of WTP for reductions in ozone pollution. (author)

  10. Temporal Variability of Daily Personal Magnetic Field Exposure Metrics in Pregnant Women

    OpenAIRE

    Lewis, Ryan C.; Evenson, Kelly R.; Savitz, David A.; Meeker, John D.

    2014-01-01

    Recent epidemiology studies of power-frequency magnetic fields and reproductive health have characterized exposures using data collected from personal exposure monitors over a single day, possibly resulting in exposure misclassification due to temporal variability in daily personal magnetic field exposure metrics, but relevant data in adults are limited. We assessed the temporal variability of daily central tendency (time-weighted average, median) and peak (upper percentiles, maximum) persona...

  11. Stratospheric ozone changes under solar geoengineering: implications for UV exposure and air quality

    Directory of Open Access Journals (Sweden)

    P. J. Nowack

    2016-03-01

    Full Text Available Various forms of geoengineering have been proposed to counter anthropogenic climate change. Methods which aim to modify the Earth's energy balance by reducing insolation are often subsumed under the term solar radiation management (SRM. Here, we present results of a standard SRM modelling experiment in which the incoming solar irradiance is reduced to offset the global mean warming induced by a quadrupling of atmospheric carbon dioxide. For the first time in an atmosphere–ocean coupled climate model, we include atmospheric composition feedbacks for this experiment. While the SRM scheme considered here could offset greenhouse gas induced global mean surface warming, it leads to important changes in atmospheric composition. We find large stratospheric ozone increases that induce significant reductions in surface UV-B irradiance, which would have implications for vitamin D production. In addition, the higher stratospheric ozone levels lead to decreased ozone photolysis in the troposphere. In combination with lower atmospheric specific humidity under SRM, this results in overall surface ozone concentration increases in the idealized G1 experiment. Both UV-B and surface ozone changes are important for human health. We therefore highlight that both stratospheric and tropospheric ozone changes must be considered in the assessment of any SRM scheme, due to their important roles in regulating UV exposure and air quality.

  12. Ozone exposure triggers the emission of herbivore-induced plant volatiles, but does not disturb tritrophic signalling

    Energy Technology Data Exchange (ETDEWEB)

    Vuorinen, Terhi; Nerg, Anne-Marja; Holopainen, Jarmo K

    2004-09-01

    We evaluated the similarities between ozone-induced and mite-induced emission of volatile organic compounds (VOCs) from lima beans, and tested the response of the natural enemies of herbivores to these emissions using trophic system of two-spotted spider mites and predatory mites. The acute ozone-exposure and spider mite-infestation induced the emission of two homoterpenes, (E)-4,8-dimethyl-1,3,7-nonatriene and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, and (Z)-3-hexenyl acetate. Only plants with spider mite-infestation emitted the monoterpene (E)-{beta}-ocimene. Predatory mites were equally attracted to ozone-exposed and unexposed plants, but discriminated between spider mite-infested and uninfested plants, when both were exposed to ozone. The similarities between ozone and herbivore-induced VOCs suggest that plant defence against phytotoxic ozone and the production of VOCs for attraction of the natural enemies of herbivores may have adaptive coevolution. However, the expected elevated ozone concentrations in future may not disturb tritrophic signalling, unless herbivore-induced VOCs are lost in the process of aerosol formation.

  13. Ozone exposure triggers the emission of herbivore-induced plant volatiles, but does not disturb tritrophic signalling

    International Nuclear Information System (INIS)

    Vuorinen, Terhi; Nerg, Anne-Marja; Holopainen, Jarmo K.

    2004-01-01

    We evaluated the similarities between ozone-induced and mite-induced emission of volatile organic compounds (VOCs) from lima beans, and tested the response of the natural enemies of herbivores to these emissions using trophic system of two-spotted spider mites and predatory mites. The acute ozone-exposure and spider mite-infestation induced the emission of two homoterpenes, (E)-4,8-dimethyl-1,3,7-nonatriene and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, and (Z)-3-hexenyl acetate. Only plants with spider mite-infestation emitted the monoterpene (E)-β-ocimene. Predatory mites were equally attracted to ozone-exposed and unexposed plants, but discriminated between spider mite-infested and uninfested plants, when both were exposed to ozone. The similarities between ozone and herbivore-induced VOCs suggest that plant defence against phytotoxic ozone and the production of VOCs for attraction of the natural enemies of herbivores may have adaptive coevolution. However, the expected elevated ozone concentrations in future may not disturb tritrophic signalling, unless herbivore-induced VOCs are lost in the process of aerosol formation

  14. OMI/Aura TOMS-Like Ozone and Radiative Cloud Fraction Daily L3 Global 0.25x0.25 deg V003

    Data.gov (United States)

    National Aeronautics and Space Administration — The Version-003 of Level-3 Aura/OMI daily global TOMS-Like Total Column Ozone gridded product (OMTO3e) is generated by the NASA OMI science team by picking the best...

  15. Global Ozone Distribution relevant to Human Health: Metrics and present day levels from the Tropospheric Ozone Assessment Report (TOAR)

    Science.gov (United States)

    Fleming, Z. L.; Doherty, R. M.; von Schneidemesser, E.; Cooper, O. R.; Malley, C.; Colette, A.; Xu, X.; Pinto, J. P.; Simpson, D.; Schultz, M. G.; Hamad, S.; Moola, R.; Solberg, S.; Feng, Z.

    2017-12-01

    Using stations from the TOAR surface ozone database, this study quantifies present-day global and regional distributions of five ozone metrics relevant for both short-term and long-term human exposure. These metrics were explored at ozone monitoring sites globally, and re-classified for this project as urban or non-urban using population densities and night-time lights. National surface ozone limit values are usually related to an annual number of exceedances of daily maximum 8-hour running mean (MDA8), with many countries not even having any ozone limit values. A discussion and comparison of exceedances in the different ozone metrics, their locations and the seasonality of exceedances provides clues as to the regions that potentially have more serious ozone health implications. Present day ozone levels (2010-2014) have been compared globally and show definite geographical differences (see Figure showing the annual 4th highest MDA8 for present day ozone for all non-urban stations). Higher ozone levels are seen in western compared to eastern US, and between southern and northern Europe, and generally higher levels in east Asia. The metrics reflective of peak concentrations show highest values in western North America, southern Europe and East Asia. A number of the metrics show similar distributions of North-South gradients, most prominent across Europe and Japan. The interquartile range of the regional ozone metrics was largest in East Asia, higher for urban stations in Asia but higher for non-urban stations in Europe and North America. With over 3000 monitoring stations included in this analysis and despite the higher densities of monitoring stations in Europe, north America and East Asia, this study provides the most comprehensive global picture to date of surface ozone levels in terms of health-relevant metrics.

  16. Ozone changes under solar geoengineering: implications for UV exposure and air quality

    Science.gov (United States)

    Nowack, P. J.; Abraham, N. L.; Braesicke, P.; Pyle, J. A.

    2015-11-01

    Various forms of geoengineering have been proposed to counter anthropogenic climate change. Methods which aim to modify the Earth's energy balance by reducing insolation are often subsumed under the term Solar Radiation Management (SRM). Here, we present results of a standard SRM modelling experiment in which the incoming solar irradiance is reduced to offset the global mean warming induced by a quadrupling of atmospheric carbon dioxide. For the first time in an atmosphere-ocean coupled climate model, we include atmospheric composition feedbacks such as ozone changes under this scenario. Including the composition changes, we find large reductions in surface UV-B irradiance, with implications for vitamin D production, and increases in surface ozone concentrations, both of which could be important for human health. We highlight that both tropospheric and stratospheric ozone changes should be considered in the assessment of any SRM scheme, due to their important roles in regulating UV exposure and air quality.

  17. Adaptation of radish Raphanus sativus L. in response to continuous exposure to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Walmsley, L.; Ashmore, M.R.; Bell, J.N.B.

    1980-01-01

    A comparison was made between the development of radish Raphanus sativus L. cv. Cherry Belle in clean air and under continuous exposure to 0 x 17 ppm (340 ..mu..g m/sup -3/) of ozone. The area and dry weight of the individual leaves, and the dry weight of other plant organs, were determined at frequent, regular intervals throughout the experiment. Although the commercial yield of the ozone-treated plants, expressed as hypocotyl dry weight, was significantly reduced, changes in the pattern of development of these plants were observed which were of adaptive value. The pattern of assimilate distribution was altered so that new leaves were produced more rapidly in the ozone-treated plants. These later leaves were more resistant to ozone, showing a slower rate of senescence than the cotyledons or first leaves. Measurements of stomatal resistance suggested that this was an acquired, rather than an inherent, characteristic of the later leaves. By the end of the experiment, the relative growth rates in the two treatments did not differ significantly.

  18. Commuters’ Personal Exposure to Ambient and Indoor Ozone in Athens, Greece

    Directory of Open Access Journals (Sweden)

    Krystallia K. Kalimeri

    2017-07-01

    Full Text Available This pilot study aimed to monitor the residential/office indoor, outdoor, and personal levels of ozone for people living, working, and commuting in Athens, Greece. Participants (16 persons of this study worked at the same place. Passive sampling analysis results did not indicate any limit exceedance (Directive 2008/50/EC: 120 µg/m3, World Health Organization (WHO Air Quality Guidelines 2005: 100 µg/m3. The highest “house-outdoor” concentration was noticed for participants living in the north suburbs of Athens, confirming the photochemical ozone formation at the northern parts of the basin during southwestern prevailing winds. The residential indoor to outdoor ratio (I/O was found to be significantly lower than unity, underlying the outdoor originality of the pollutant. The highest “office-indoor” concentration was observed in a ground-level building, characterized by the extensive use of photocopy machines and printers. Personal ozone levels were positively correlated only with indoor-office concentrations. A clear correlation of personal ozone levels to the time spent by the individuals during moving/staying outdoors was observed. On the other hand, no correlation was observed when focusing only on commuting time, due to the fact that transit time includes both on-foot and in-vehicle time periods, therefore activities associated with increased exposure levels, but also with pollutants removal by recirculating air filtering systems, respectively.

  19. Biomarkers of oxidative stress study V: ozone exposure of rats and its effect on lipids, proteins, and DNA in plasma and urine.

    Science.gov (United States)

    Kadiiska, Maria B; Basu, Samar; Brot, Nathan; Cooper, Christopher; Saari Csallany, A; Davies, Michael J; George, Magdalene M; Murray, Dennis M; Jackson Roberts, L; Shigenaga, Mark K; Sohal, Rajindar S; Stocker, Roland; Van Thiel, David H; Wiswedel, Ingrid; Hatch, Gary E; Mason, Ronald P

    2013-08-01

    Ozone exposure effect on free radical-catalyzed oxidation products of lipids, proteins, and DNA in the plasma and urine of rats was studied as a continuation of the international Biomarker of Oxidative Stress Study (BOSS) sponsored by NIEHS/NIH. The goal was to identify a biomarker for ozone-induced oxidative stress and to assess whether inconsistent results often reported in the literature might be due to the limitations of the available methods for measuring the various types of oxidative products. The time- and dose-dependent effects of ozone exposure on rat plasma lipid hydroperoxides, malondialdehyde, F2-isoprostanes, protein carbonyls, methionine oxidation, and tyrosine- and phenylalanine oxidation products, as well as urinary malondialdehyde and F2-isoprostanes were investigated with various techniques. The criterion used to recognize a marker in the model of ozone exposure was that a significant effect could be identified and measured in a biological fluid seen at both doses at more than one time point. No statistically significant differences between the experimental and the control groups at either ozone dose and time point studied could be identified in this study. Tissue samples were not included. Despite all the work accomplished in the BOSS study of ozone, no available product of oxidation in biological fluid has yet met the required criteria of being a biomarker. The current negative findings as a consequence of ozone exposure are of great importance, because they document that in complex systems, as the present in vivo experiment, the assays used may not provide meaningful data of ozone oxidation, especially in human studies. Published by Elsevier Inc.

  20. Ozonation control and effects of ozone on water quality in recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Rojas-Tirado, Paula Andrea; Chetri, Ravi K.

    2018-01-01

    To address the undesired effect of chemotherapeutants in aquaculture, ozone has been suggested as an alternative to improve water quality. To ensure safe and robust treatment, it is vital to define the ozone demand and ozone kinetics of the specific water matrix to avoid ozone overdose. Different...... ozone dosages were applied to water in freshwater recirculating aquaculture systems (RAS). Experiments were performed to investigate ozone kinetics and demand, and to evaluate the effects on the water quality, particularly in relation to fluorescent organic matter. This study aimed at predicting...... a suitable ozone dosage for water treatment based on daily ozone demand via laboratory studies. These ozone dosages will be eventually applied and maintained at these levels in pilot-scale RAS to verify predictions. Selected water quality parameters were measured, including natural fluorescence and organic...

  1. Are Bavarian Forests (southern Germany) at risk from ground-level ozone? Assessment using exposure and flux based ozone indices

    International Nuclear Information System (INIS)

    Baumgarten, Manuela; Huber, Christian; Bueker, Patrick; Emberson, Lisa; Dietrich, Hans-Peter; Nunn, Angela J.; Heerdt, Christian; Beudert, Burkhard; Matyssek, Rainer

    2009-01-01

    Exposure and flux-based indices of O 3 risk were compared, at 19 forest locations across Bavaria in southern Germany from 2002 to 2005; leaf symptoms on mature beech trees found at these locations were also examined for O 3 injury. O 3 flux modelling was performed using continuously recorded O 3 concentrations in combination with meteorological and soil moisture data collected from Level II forest sites. O 3 measurements at nearby rural open-field sites proved appropriate as surrogates in cases where O 3 data were lacking at forest sites (with altitude-dependent average differences of about 10% between O 3 concentrations). Operational thresholds of biomass loss for both O 3 indices were exceeded at the majority of the forest locations, suggesting similar risk under long-term average climate conditions. However, exposure-based indices estimated higher O 3 risk during dry years as compared to the flux-based approach. In comparison, minor O 3 -like leaf injury symptoms were detected only at a few of the forest sites investigated. Relationships between flux-based risk thresholds and tree response need to be established for mature forest stands for validation of predicted growth reductions under the prevailing O 3 regimes. - Exposure- and flux-based ozone indices suggest Bavarian forests to be at risk from ozone; the flux-based index offers a means of incorporating stand-specific and ecological variables that influence risk.

  2. Racial Differences in Exposure and Reactivity to Daily Family Stressors

    Science.gov (United States)

    Cichy, Kelly E.; Stawski, Robert S.; Almeida, David M.

    2012-01-01

    Using data from the National Study of Daily Experiences, the authors examined racial differences in exposure and reactivity to daily stressors involving family members. Respondents included African American and European American adults age 34 to 84 (N = 1,931) who participated in 8 days of daily interviews during which they reported on daily…

  3. OZONE CONCENTRATION ATTRIBUTABLE PREMATURE DEATH IN POLAND

    Directory of Open Access Journals (Sweden)

    Krzysztof Skotak

    2010-03-01

    Full Text Available Ozone in the lower part of the atmosphere (troposphere, strong photochemical oxidant, is not directly emitted to the atmosphere but formed through a series of complex reactions. Ozone concentrations depends on ozone precursors air contamination (mainly nitrogen dioxide and non-methane volatile organic compounds and meteorological conditions (temperature and solar radiation. The main sectors emitted ozone precursors are road transport, power and heat generation plants, household (heating, industry, and petrol storage and distribution. Ozone and some of its precursors are also transported long distances in the atmosphere and are therefore considered a transboundary problem. As a result, the ozone concentrations are often low in busy urban areas and higher in suburban and rural areas. Nowadays, instead of particulate matter, ozone is one of the most widespread global air pollution problems. In and around urban areas, relatively large gradients of ozone can be observed. Because of its high reactivity in elevated concentrations ozone causes serious health problems and damage to ecosystems, agricultural crops and materials. Main ill-health endpoints as a results of ozone concentrations can be characterised as an effect of pulmonary and cardiovascular system, time morbidity and mortality series, development of atherosclerosis and asthma and finally reduction in life expectancy. The associations with increased daily mortality due to ozone concentrations are confirmed by many researches and epidemiological studies. Estimation of the level selected ill-health endpoints (mortality in total and due to cardiovascular and respiratory causes as a result of the short-term ozone exposure in Poland was the main aim of the project. Final results have been done based on estimation method elaborated by WHO, ozone measurements from National Air Quality Monitoring System and statistical information such as mortality rate and populations. All analysis have been done in

  4. The Variable Effects of Ozone and/or Diesel Particulate Inhalation Exposure on Allergic Airways Responses in Mice

    Science.gov (United States)

    Exposure to diesel exhaust particle matter (DEP) associated with the combustion of diesel fuel exacerbates asthma. Likewise, similar effects have been reported with exposure to the oxidizing air pollutant ozone (O3). Since levels of both pollutants in ambient air are e...

  5. Serum lipid and lipoprotein concentrations following exposure to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Vaughan, W J; Adamson, G L; Lindgren, F T; Schooley, J.C.

    1984-07-01

    The effects of exposure to ozone (O/sub 3/) on concentrations of serum lipids and lipoproteins were investigated. Male and female guinea pigs were exposed to O/sub 3/ at 1 ppm for two weeks. Serum concentrations of cholesterol, triglycerides, low density (LDL) and very low density (VLDL) lipoproteins were elevated after O/sub 3/ exposure, particularly in males. During O/sub 3/ exposure the food intake per day decreased (for a constant body weight), suggesting that metabolic rate and possibly basal metabolic rate was lower. Lung wet weights increased during O/sub 3/ exposure by 87% for males and 45% for females. When individual lung weight/body weight ratios were correlated with cholesterol and LDL values from the same animal, a high correlation is found for males (r . 0.81, P less than 0.05), suggesting that there may be a relationship between lipoprotein elevations and lung damage for males. Because elevated concentrations of lipids and lipoproteins in humans increase the risk of coronary heart disease (CHD), the lipoprotein results suggest that an epidemiological study of the incidence of CHD with metropolitan O/sub 3/ levels may be warranted.

  6. Ozone sensitivity of plants in natural communities

    Energy Technology Data Exchange (ETDEWEB)

    Treshow, M; Stewart, D

    1973-07-01

    Field fumigation studies conducted in grassland, oak, aspen, and conifer, communities established the injury threshold of prevalent plant species to ozone. Several important species, including Bromus tectorum, Quercus gambelii, and Populus tremuloides, were injured by a single 2-hours exposure to 15 pphM ozone. Over half the perennial forbs and woody species studied were visibly injured at concentrations of 30 pphM ozone or less. It is postulated that lower concentrations at prolonged or repeated exposures to ozone may impair growth and affect community vigor and stability. Continued exposure of natural plant communities to ozone is expected to initiate major shifts in the plant composition of communities. 10 references, 4 figures, 1 table.

  7. Short-term UV-B radiation and ozone exposure effects on aromatic secondary metabolite accumulation and shoot growth of flavonoid-deficient Arabidopsis mutants

    International Nuclear Information System (INIS)

    Ormrod, D.P.; Landry, L.G.; Conklin, P.L.

    1995-01-01

    The presence of UV-absorptive substances in the epidermal cells of leaves is thought to protect mesophyll tissues from the harmful effects of UV-B radiation. We examined the influence of short-term UV-B exposures on UV-absorptive (330 nm) sinapates and flavonols, and on shoot growth of the Arabidopsis wild type ecotype Landsberg erecta and two mutants. 114 deficient in chalcone synthase, and 115, deficient in chalcone/flavonone isomerase. Sequential ozone exposures were used to determine the effects of oxidative stress The levels of sinapates and flavonols on a leaf fresh weight basis increased substantially in the wild type and sinapates increased in the 114 mutant in vegetative vegetative/reproductive transitional and reproductive stage plants in response to short-term (48h) UV-B radiation. When UV-B was discontinued the levels generally decreased lo pre-exposure levels after 48 h in vegetative/reproductive but not in reproductive plants. Exposure to ozone before or alter UV-B treatment did not consistently affect the levels of these UV-absorptive compounds. Dry matter accumulation was less affected by UV-B at the vegetative and reproductive stages than at the vegetative/reproductive stage. At the vegetative/reproductive stage, shoot growth of all 3 genotypes was retarded by UV-B. Growth was not retarded by short-term ozone exposure alone but when exposure to ozone followed UV-B exposure, growth was reduced in all genotypes. Leaf cupping appeared on 115 plants exposed to UV-B

  8. Exposure to environmentally-relevant levels of ozone negatively influence pollen and fruit development

    International Nuclear Information System (INIS)

    Gillespie, Colin; Stabler, Daniel; Tallentire, Eva; Goumenaki, Eleni; Barnes, Jeremy

    2015-01-01

    A combination of in vitro and in vivo studies on tomato (Lycopersicon esculentum Mill. cv. Triton) revealed that environmentally-relevant levels of ozone (O_3) pollution adversely affected pollen germination, germ tube growth and pollen-stigma interactions – pollen originating from plants raised in charcoal-Purafil"® filtered air (CFA) exhibited reduced germ tube development on the stigma of plants exposed to environmentally-relevant levels of O_3. The O_3-induced decline in in vivo pollen viability was reflected in increased numbers of non-fertilized and fertilized non-viable ovules in immature fruit. Negative effects of O_3 on fertilization occurred regardless of the timing of exposure, with reductions in ovule viability evident in O_3 × CFA and CFA × O_3 crossed plants. This suggests O_3-induced reductions in fertilization were associated with reduced pollen viability and/or ovule development. Fruit born on trusses independently exposed to 100 nmol mol"−"1 O_3 (10 h d"−"1) from flowering exhibited a decline in seed number and this was reflected in a marked decline in the weight and size of individual fruit – a clear demonstration of the direct consequence of the effects of the pollutant on reproductive processes. Ozone exposure also resulted in shifts in the starch and ascorbic acid (Vitamin C) content of fruit that were consistent with accelerated ripening. The findings of this study draw attention to the need for greater consideration of, and possibly the adoption of weightings for the direct impacts of O_3, and potentially other gaseous pollutants, on reproductive biology during ‘risk assessment’ exercises. - Highlights: • Environmentally-relevant levels of ozone exert negative effects on pollen viability that translate into direct impacts on fruit yield. • Negative impacts of O_3 pollution on reproductive processes were evident regardless of the stage of plant development. • Exposure to environmentally-relevant levels of O_3

  9. Ozone reaction on slime mold. [Physarum polycephalum

    Energy Technology Data Exchange (ETDEWEB)

    Kanoh, F.

    1972-01-01

    To determine the effect of ozone, the motive force responsible for protoplasmic streaming in the slime mold, Physarum polycephalum was measured by the Double chamber method which was developed by Kamiya. The effects of ozone on the motive force were investigated by comparison of the Dynamoplasmogram of controls with that of ozone exposure. In the case of high concentration exposure, thickening of plasmagel, inversion of the period of flow and reduction of the extreme point were observed. Succinoxidase of exposed homogenates showed stronger activity than that of controls. It is certain that the Pasteur reaction takes place when plasmodium is kept under high ozone exposure condition. It appears that ozone inhibited a part of the process of glycolysis. 32 references, 8 figures.

  10. Ozone, Fine Particulate Matter, and Chronic Lower Respiratory Disease Mortality in the United States.

    Science.gov (United States)

    Hao, Yongping; Balluz, Lina; Strosnider, Heather; Wen, Xiao Jun; Li, Chaoyang; Qualters, Judith R

    2015-08-01

    Short-term effects of air pollution exposure on respiratory disease mortality are well established. However, few studies have examined the effects of long-term exposure, and among those that have, results are inconsistent. To evaluate long-term association between ambient ozone, fine particulate matter (PM2.5, particles with an aerodynamic diameter of 2.5 μm or less), and chronic lower respiratory disease (CLRD) mortality in the contiguous United States. We fit Bayesian hierarchical spatial Poisson models, adjusting for five county-level covariates (percentage of adults aged ≥65 years, poverty, lifetime smoking, obesity, and temperature), with random effects at state and county levels to account for spatial heterogeneity and spatial dependence. We derived county-level average daily concentration levels for ambient ozone and PM2.5 for 2001-2008 from the U.S. Environmental Protection Agency's down-scaled estimates and obtained 2007-2008 CLRD deaths from the National Center for Health Statistics. Exposure to ambient ozone was associated with an increased rate of CLRD deaths, with a rate ratio of 1.05 (95% credible interval, 1.01-1.09) per 5-ppb increase in ozone; the association between ambient PM2.5 and CLRD mortality was positive but statistically insignificant (rate ratio, 1.07; 95% credible interval, 0.99-1.14). This study links air pollution exposure data with CLRD mortality for all 3,109 contiguous U.S. counties. Ambient ozone may be associated with an increased rate of death from CLRD in the contiguous United States. Although we adjusted for selected county-level covariates and unobserved influences through Bayesian hierarchical spatial modeling, the possibility of ecologic bias remains.

  11. A probabilistic assessment of health risks associated with short-term exposure to tropospheric ozone

    Energy Technology Data Exchange (ETDEWEB)

    Whitfield, R.G; Biller, W.F.; Jusko, M.J.; Keisler, J.M.

    1996-06-01

    The work described in this report is part of a larger risk assessment sponsored by the U.S. Environmental Protection Agency. Earlier efforts developed exposure-response relationships for acute health effects among populations engaged in heavy exertion. Those efforts also developed a probabilistic national ambient air quality standards exposure model and a general methodology for integrating probabilistic exposure-response relation- ships and exposure estimates to calculate overall risk results. Recently published data make it possible to model additional health endpoints (for exposure at moderate exertion), including hospital admissions. New air quality and exposure estimates for alternative national ambient air quality standards for ozone are combined with exposure-response models to produce the risk results for hospital admissions and acute health effects. Sample results explain the methodology and introduce risk output formats.

  12. DNA bulky adducts in a Mediterranean population correlate with environmental ozone concentration, an indicator of photochemical smog.

    Science.gov (United States)

    Palli, Domenico; Saieva, Calogero; Grechi, Daniele; Masala, Giovanna; Zanna, Ines; Barbaro, Antongiulio; Decarli, Adriano; Munnia, Armelle; Peluso, Marco

    2004-03-01

    Ozone (O(3)), the major oxidant component in photochemical smog, mostly derives from photolysis of nitrogen dioxide. O(3) may have biologic effects directly and/or via free radicals reacting with other primary pollutants and has been reported to influence daily mortality and to increase lung cancer risk. Although DNA damage may be caused by ozone itself, only other photochemical reaction products (as oxidised polycyclic aromatic hydrocarbons) may form bulky DNA adducts, a reliable biomarker of genotoxic damage and cancer risk, showing a seasonal trend. In a large series consisting of 320 residents in the metropolitan area of Florence, Italy, enrolled in a prospective study for the period 1993-1998 (206 randomly sampled volunteers, 114 traffic-exposed workers), we investigated the correlation between individual levels of DNA bulky adducts and a cumulative O(3) exposure score. The average O(3) concentrations were calculated for different time windows (0-5 to 0-90 days) prior to blood drawing for each participant, based on daily measurements provided by the local monitoring system. Significant correlations between DNA adduct levels and O3 cumulative exposure scores in the last 2-8 weeks before enrollment emerged in never smokers. Correlations were highest in the subgroup of never smokers residing in the urban area and not occupationally exposed to vehicle traffic pollution, with peak values for average concentrations 4-6 weeks before enrollment (r = 0.34). Our current findings indicate that DNA adduct formation may be modulated by individual characteristics and by the cumulative exposure to environmental levels of ozone in the last 4-6 weeks, possibly through ozone-associated reactive pollutants. Copyright 2003 Wiley-Liss, Inc.

  13. Non-daily pre-exposure prophylaxis for HIV prevention

    Science.gov (United States)

    Anderson, Peter L.; García-Lerma, J. Gerardo; Heneine, Walid

    2015-01-01

    Purpose of review To discuss non-daily pre-exposure prophylaxis (PrEP) modalities that may provide advantages compared with daily PrEP in cost and cumulative toxicity, but may have lower adherence forgiveness. Recent Findings Animal models have informed our understanding of early viral transmission events, which help guide event-driven PrEP dosing strategies. These models indicate early establishment of viral replication in rectal or cervicovaginal tissues, so event-driven PrEP should rapidly deliver high mucosal drug concentrations within hours of the potential exposure event. Macaque models have demonstrated the high biological efficacy for event-driven dosing of oral tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) against both vaginal and rectal virus transmission. In humans, the IPERGAY study demonstrated 86% efficacy for event-driven oral TDF/FTC dosing among men who have sex with men (MSM), while no similar efficacy data are available on women or heterosexual men. The HPTN 067 study showed that certain MSM populations adhere well to non-daily PrEP while other populations of women adhere more poorly to non-daily versus daily regimens. Pharmacokinetic studies following oral TDF/FTC dosing in humans, indicate that TFV-diphosphate (the active form of TFV) accumulates to higher concentrations in rectal versus cervicovaginal tissue but non-adherence in trials complicates the interpretation of differential mucosal drug concentrations. Summary Event-driven dosing for TFV-based PrEP has promise for HIV prevention in MSM. Future research of event-driven PrEP in women and heterosexual men should be guided by a better understanding of the importance of mucosal drug concentrations for PrEP efficacy and its sensitivity to adherence. PMID:26633641

  14. Adrenal-derived stress hormones modulate ozone-induced ...

    Science.gov (United States)

    Ozone-induced systemic effects are modulated through activation of the neuro-hormonal stress response pathway. Adrenal demedullation (DEMED)or bilateral total adrenalectomy (ADREX) inhibits systemic and pulmonary effect of acute ozone exposure. To understand the influence of adrenal-derived stress hormones in mediating ozone-induced lung injury/inflammation, we assessed global gene expression (mRNA sequencing) and selected proteins in lung tissues from male Wistar-Kyoto rats that underwent DEMED, ADREX, or sham surgery (SHAM)prior to their exposure to air or ozone (1 ppm),4 h/day for 1 or 2days. Ozone exposure significantly changed the expression of over 2300 genes in lungs of SHAM rats, and these changes were markedly reduced in DEMED and ADREX rats. SHAM surgery but not DEMED or ADREX resulted in activation of multiple ozone-responsive pathways, including glucocorticoid, acute phase response, NRF2, and Pl3K-AKT.Predicted targets from sequencing data showed a similarity between transcriptional changes induced by ozone and adrenergic and steroidal modulation of effects in SHAM but not ADREX rats. Ozone-induced Increases in lung 116 in SHAM rats coincided with neutrophilic Inflammation, but were diminished in DEMED and ADREX rats. Although ozone exposure in SHAM rats did not significantly alter mRNA expression of lfny and 11-4, the IL-4 protein and ratio of IL-4 to IFNy (IL-4/IFNy) proteins increased suggesting a tendency for a Th2 response. This did not occur

  15. Pulmonary Ozone Exposure Alters Essential Metabolic Pathways involved in Glucose Homeostasis in the Liver

    Science.gov (United States)

    Pulmonary Ozone Exposure Alters Essential Metabolic Pathways involved in Glucose Homeostasis in the Liver D.B. Johnson, 1 W.O. Ward, 2 V.L. Bass, 2 M.C.J. Schladweiler, 2A.D. Ledbetter, 2 D. Andrews, and U.P. Kodavanti 2 1 Curriculum in Toxicology, UNC School of Medicine, Cha...

  16. Growth response of Pinus ponderosa seedlings and mature tree branches to acid rain and ozone exposure

    International Nuclear Information System (INIS)

    Anderson, P.D.; Houpis, J.L.J.; Helms, J.A.

    1994-10-01

    Forests of the central and southern Sierra Nevada in California have been subjected to chronic damage by ozone and other atmospheric pollutants for the past several decades. Until recently, pollutant exposure of northern Sierra Nevada forests has been mild but increasing population and changes in land use throughout the Sacramento Valley and Sierra Nevada foothills may lead to increased pollutant damage in these forests. Although, better documented in other regions of the United States, little is known regarding the potential for acidic precipitation damage to Sierra Nevada forests. Only recently have studies directed towards understanding the potential interactive effects of ozone and acidic precipitation been undertaken. A key issue in resolving potential regional impacts of pollutants on forests is the extent to which research results can be scaled across genotypes and life-stages. Most of the pollution research to date has been performed using seedlings with varying degrees of genetic control. It is important to determine if the results obtained in such studies can be extrapolated to mature trees and to different genetic sources. In this paper, we present results from a one-year study examining the interactive effects of foliar exposure to acidic rain and ozone on the growth of ponderosa pine (Pinus ponderosa), a conifer known to be sensitive to ozone. The response to pollutants is characterized for both seedlings and mature tree branches of three genotypes grown in a common environment

  17. Hypoxia-induced pulmonary arterial hypertension augments lung injury and airway reactivity caused by ozone exposure

    International Nuclear Information System (INIS)

    Zychowski, Katherine E.; Lucas, Selita N.; Sanchez, Bethany; Herbert, Guy; Campen, Matthew J.

    2016-01-01

    Ozone (O 3 )-related cardiorespiratory effects are a growing public health concern. Ground level O 3 can exacerbate pre-existing respiratory conditions; however, research regarding therapeutic interventions to reduce O 3 -induced lung injury is limited. In patients with chronic obstructive pulmonary disease, hypoxia-associated pulmonary hypertension (HPH) is a frequent comorbidity that is difficult to treat clinically, yet associated with increased mortality and frequency of exacerbations. In this study, we hypothesized that established HPH would confer vulnerability to acute O 3 pulmonary toxicity. Additionally, we tested whether improvement of pulmonary endothelial barrier integrity via rho-kinase inhibition could mitigate pulmonary inflammation and injury. To determine if O 3 exacerbated HPH, male C57BL/6 mice were subject to either 3 weeks continuous normoxia (20.9% O 2 ) or hypoxia (10.0% O 2 ), followed by a 4-h exposure to either 1 ppm O 3 or filtered air (FA). As an additional experimental intervention fasudil (20 mg/kg) was administered intraperitoneally prior to and after O 3 exposures. As expected, hypoxia significantly increased right ventricular pressure and hypertrophy. O 3 exposure in normoxic mice caused lung inflammation but not injury, as indicated by increased cellularity and edema in the lung. However, in hypoxic mice, O 3 exposure led to increased inflammation and edema, along with a profound increase in airway hyperresponsiveness to methacholine. Fasudil administration resulted in reduced O 3 -induced lung injury via the enhancement of pulmonary endothelial barrier integrity. These results indicate that increased pulmonary vascular pressure may enhance lung injury, inflammation and edema when exposed to pollutants, and that enhancement of pulmonary endothelial barrier integrity may alleviate such vulnerability. - Highlights: • Environmental exposures can exacerbate chronic obstructive pulmonary disease (COPD). • It is unknown if comorbid

  18. New Directions: Ozone-initiated reaction products indoors may be more harmful than ozone itself

    Science.gov (United States)

    Weschler, Charles J.

    2004-10-01

    Epidemiological studies have found associations between ozone concentrations measured at outdoor monitoring stations and certain adverse health outcomes. As a recent example, Gent et al. (2003, Journal of the American Medical Association 290, 1859-1867) have observed an association between ozone levels and respiratory symptoms as well as the use of maintenance medication by 271 asthmatic children living in Connecticut and the Springfield area of Massachusetts. In another example, Gilliland et al. (2001, Epidemiology 12, 43-54) detected an association between short-term increases in ozone levels and increased absences among 4th grade students from 12 southern California communities during the period from January to June 1996. Although children may spend a significant amount of time outdoors, especially during periods when ozone levels are elevated, they spend a much larger fraction of their time indoors. I hypothesize that exposure to the products of ozone-initiated indoor chemistry is more directly responsible for the health effects observed in the cited epidemiological studies than is exposure to outdoor ozone itself.

  19. The Tropospheric Ozone Assessment Report (TOAR): A community-wide effort to quantify tropospheric ozone in a rapidly changing world

    Science.gov (United States)

    Cooper, O. R.; Schultz, M.; Paoletti, E.; Galbally, I. E.; Naja, M. K.; Tarasick, D. W.; Evans, M. J.; Thompson, A. M.

    2017-12-01

    Tropospheric ozone is a greenhouse gas and pollutant detrimental to human health and crop and ecosystem productivity. Since 1990 a large portion of the anthropogenic emissions that react in the atmosphere to produce ozone has shifted from North America and Europe to Asia. This rapid shift, coupled with limited ozone monitoring in developing nations, left scientists unable to answer the most basic questions: Which regions of the world have the greatest human and plant exposure to ozone pollution? Is ozone continuing to decline in nations with strong emissions controls? To what extent is ozone increasing in the developing world? How can the atmospheric sciences community facilitate access to the ozone metrics necessary for quantifying ozone's impact on human health and crop/ecosystem productivity? To answer these questions the International Global Atmospheric Chemistry Project (IGAC) initiated the Tropospheric Ozone Assessment Report (TOAR). With over 220 member scientists and air quality specialists from 36 nations, TOAR's mission is to provide the research community with an up-to-date scientific assessment of tropospheric ozone's global distribution and trends from the surface to the tropopause. TOAR has also built the world's largest database of surface ozone observations and generated ozone exposure and dose metrics at thousands of measurement sites around the world, freely accessible for research on the global-scale impact of ozone on climate, human health and crop/ecosystem productivity. Plots of these metrics show the regions of the world with the greatest ozone exposure for humans and crops/ecosystems, at least in areas where observations are available. The results also highlight regions where air quality is improving and where it has degraded. TOAR has also conducted the first intercomparison of tropospheric column ozone from ozonesondes and multiple satellite instruments, which provide similar estimates of the present-day tropospheric ozone burden.

  20. Bittersweet: Real-Time, Dynamic Changes in Blood Glucose Levels during an Acute Ozone Exposure in Rats

    Science.gov (United States)

    In humans and rats, acute exposures to ozone have been shown to activate the sympathetic-adrenal-medullary and hypothalamic-pituitary-adrenal axes to induce multi-organ metabolic alterations including impaired glucose homeostasis. These findings have largely been gleaned from on...

  1. Tropospheric Ozone Assessment Report: Present-day ozone distribution and trends relevant to human health

    Directory of Open Access Journals (Sweden)

    Zoë L. Fleming

    2018-02-01

    Full Text Available This study quantifies the present-day global and regional distributions (2010–2014 and trends (2000–2014 for five ozone metrics relevant for short-term and long-term human exposure. These metrics, calculated by the Tropospheric Ozone Assessment Report, are: 4th highest daily maximum 8-hour ozone (4MDA8; number of days with MDA8 > 70 ppb (NDGT70, SOMO35 (annual Sum of Ozone Means Over 35 ppb and two seasonally averaged metrics (3MMDA1; AVGMDA8. These metrics were explored at ozone monitoring sites worldwide, which were classified as urban or non-urban based on population and nighttime lights data. Present-day distributions of 4MDA8 and NDGT70, determined predominantly by peak values, are similar with highest levels in western North America, southern Europe and East Asia. For the other three metrics, distributions are similar with North–South gradients more prominent across Europe and Japan. Between 2000 and 2014, significant negative trends in 4MDA8 and NDGT70 occur at most US and some European sites. In contrast, significant positive trends are found at many sites in South Korea and Hong Kong, with mixed trends across Japan. The other three metrics have similar, negative trends for many non-urban North American and some European and Japanese sites, and positive trends across much of East Asia. Globally, metrics at many sites exhibit non-significant trends. At 59% of all sites there is a common direction and significance in the trend across all five metrics, whilst 4MDA8 and NDGT70 have a common trend at ~80% of all sites. Sensitivity analysis shows AVGMDA8 trends differ with averaging period (warm season or annual. Trends are unchanged at many sites when a 1995–2014 period is used; although fewer sites exhibit non-significant trends. Over the longer period 1970–2014, most Japanese sites exhibit positive 4MDA8/SOMO35 trends. Insufficient data exist to characterize ozone trends for the rest of Asia and other world regions.

  2. Passive monitoring techniques for evaluating atmospheric ozone and nitrogen exposure and deposition to California ecosystems

    Science.gov (United States)

    Mark E. Fenn; Andrzej Bytnerowicz; Susan L. Schilling

    2018-01-01

    Measuring the exposure of ecosystems to ecologically relevant pollutants is needed for evaluating ecosystem effects and to identify regions and resources at risk. In California, ozone (O3) and nitrogen (N) pollutants are of greatest concern for ecological effects. "Passive" monitoring methods have been developed to obtain spatially...

  3. Ozone and limonene in indoor air: a source of submicron particle exposure.

    Science.gov (United States)

    Wainman, T; Zhang, J; Weschler, C J; Lioy, P J

    2000-12-01

    overall particle exposure. This study provides data for assessing the impact of outdoor ozone on indoor particles. This is important to determine the efficacy of the mass-based particulate matter standards in protecting public health because the indoor secondary particles can vary coincidently with the variations of outdoor fine particles in summer.

  4. Health Effects of Ozone Pollution

    Science.gov (United States)

    Inhaling ozone can cause coughing, shortness of breath, worse asthma or bronchitis symptoms, and irritation and damage to airways.You can reduce your exposure to ozone pollution by checking air quality where you live.

  5. Trends in Pinus ponderosa foliar pigment concentration due to chronic exposure of ozone and acid rain

    International Nuclear Information System (INIS)

    Neuman, L.; Houpis, J.; Anderson, P.

    1991-01-01

    To determine the effects of ozone and acid rain on mature Ponderosa pine trees, Lawrence Livermore National Lab. has collaborated with University of California Berkeley, University of California Davis, California State University Chico, and the US Forest Service at the latter's Chico Tree Improvement Center. Foliar tissue from mature grafted scions of Pinus ponderosa were exposed to two times ambient ozone for ten months and to acid rain (3.0 pH) weekly for 10 weeks using branch exposure chambers. Pigment extracts were analyzed spectrophotometrically for concentrations of chlorophylls a and b, and carotenoid pigments, at 662 nm, 644 nm, and 470 nm, respectively. Pigment concentrations were expressed on a surface area basis. Preliminary results revealed that chlorophyll a showed a downward trend due to the ozone treatment. Acid rain caused no effects on these three pigments, however, chlorophyll b showed an upward trend due to the interaction of ozone and acid rain. The carotenoid pigments showed no changes due to the treatments either singly, or in combination

  6. Effect of Tin Electrode (Sn, Electrode Distance and Thin Layer Size of Zinc Phthalocyanine (ZnPc to Resistance Changes With Ozone Exposure

    Directory of Open Access Journals (Sweden)

    Agustina Mogi

    2018-01-01

    Full Text Available This study was aimed to determine the effect of tin electrode distances and the thickness of a thin layer of ZnPc (Zinc phtyalocyanine toward changes in resistance with ozone exposure. Tin deposition on the glass surface was conducted using spraying method. The reaction between ozone and ZnPc produces electrical properties that can be read through the resistance value of the multimeter. Based on this study, it was investigated that the smaller a distance between the electrode and the thicker deposition of ZnPc lead to the less resistance. This showed that a thin layer of the conductivity increases along with the longer exposure to ozone gas. The movement of electrons with the hole was free.

  7. Temporal variability of daily personal magnetic field exposure metrics in pregnant women.

    Science.gov (United States)

    Lewis, Ryan C; Evenson, Kelly R; Savitz, David A; Meeker, John D

    2015-01-01

    Recent epidemiology studies of power-frequency magnetic fields and reproductive health have characterized exposures using data collected from personal exposure monitors over a single day, possibly resulting in exposure misclassification due to temporal variability in daily personal magnetic field exposure metrics, but relevant data in adults are limited. We assessed the temporal variability of daily central tendency (time-weighted average, median) and peak (upper percentiles, maximum) personal magnetic field exposure metrics over 7 consecutive days in 100 pregnant women. When exposure was modeled as a continuous variable, central tendency metrics had substantial reliability, whereas peak metrics had fair (maximum) to moderate (upper percentiles) reliability. The predictive ability of a single-day metric to accurately classify participants into exposure categories based on a weeklong metric depended on the selected exposure threshold, with sensitivity decreasing with increasing exposure threshold. Consistent with the continuous measures analysis, sensitivity was higher for central tendency metrics than for peak metrics. If there is interest in peak metrics, more than 1 day of measurement is needed over the window of disease susceptibility to minimize measurement error, but 1 day may be sufficient for central tendency metrics.

  8. The effect of chronic ozone exposure on the activation of endoplasmic reticulum stress and apoptosis in rat hippocampus

    Directory of Open Access Journals (Sweden)

    Erika Rodríguez-Martínez

    2016-10-01

    Full Text Available The chronic exposure to low doses of ozone, like in environmental pollution, leads to a state of oxidative stress, which has been proposed to contribute to neurodegenerative disorders, including Alzheimer's disease. It induces an increase of calcium in the endoplasmic reticulum (ER, which produces ER stress. On the other hand, different studies show that, in diseases such as Alzheimer’s, there exist disturbances in protein folding where ER plays an important role. The objective of this study was to evaluate the state of chronic oxidative stress on ER stress and its relationship with apoptotic death in the hippocampus of rats exposed to low doses of ozone. We used 108 male Wistar rats randomly divided into five groups. The groups received one of the following treatments: 1 Control (air, 2 Ozone (O3 7 days, 3 O3 15 days, 4 O3 30 days, 5 O3 60 days, and 6 O3 90 days. Two hours after each treatment, the animals were sacrificed and the hippocampus was extracted. Afterwards, the tissue was processed for western blot and immunohistochemistry using the following antibodies: ATF6, GRP8 and caspase 12. It was also performed TUNEL assay and electronic microscopy. Our results show an increase in ATF6, GRP78 and caspase 12 as well as ER ultrastructural alterations and an increase of TUNEL positive cells after 60 and 90 days of exposure to ozone. With the obtained results, we can conclude that oxidative stress induced by chronic exposure to low doses of ozone leads to ER stress. ER stress activates ATF6 inducing the increase of GRP78 in the cytoplasm, which leads to the increase in the nuclear translocation of ATF6. Finally, the translocation creates a vicious cycle that, together with the activation of the cascade for apoptotic cell death, contributes to the maintenance of ER stress. These events potentially contribute in the neurodegeneration processes in diseases like Alzheimer’s Disease.

  9. Destruction of enzymatic activities of corn and soybean leaves exposed to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Leffler, H R; Cherry, J H

    1974-01-01

    Experiments were conducted to determine the effects of a single ozone exposure on selected enzymatic activities and chlorophyll contents of corn and soybean seedlings. Both nitrite reductase activity and chlorophyll content of the seedlings were found to be quite sensitive to ozonation and were seen to decrease as much as 50% after exposure to 80 parts per hundred million (pphm) ozone. After exposure to lower levels of ozone, less-pronounced decreases were observed. Nitrate reductase activity was reduced only after exposure to seedling leaf tissues to high concentrations of ozone. These results are discussed in relation to the concept of a two-phase response to oxidant exposure. The first phase is at the chloroplast level and is quite sensitive to the low as well as the high concentrations of ozone; the second is at the cellular level and is relatively resistant to all but the highest ozone concentrations. 27 references, 2 tables.

  10. Human mortality effects of future concentrations of tropospheric ozone

    International Nuclear Information System (INIS)

    West, J.; Szopa, S.; Hauglustaine, D.A.

    2007-01-01

    Here we explore the effects of projected future changes in global ozone concentrations on premature human mortality, under three scenarios for 2030. We use daily surface ozone concentrations from a global atmospheric transport and chemistry model, and ozone-mortality relationships from daily time-series studies. The population-weighted annual average 8-h daily maximum ozone is projected to increase, relative to the present, in each of ten world regions under the SRES A2 scenario and the current legislation (CLE) scenario, with the largest growth in tropical regions, while decreases are projected in each region in the maximum feasible reduction (MFR) scenario. Emission reductions in the CLE scenario, relative to A2, are estimated to reduce about 190,000 premature human mortalities globally in 2030, with the most avoided mortalities in Africa. The MFR scenario will avoid about 460,000 premature mortalities relative to A2 in 2030, and 270,000 relative to CLE, with the greatest reductions in South Asia. (authors)

  11. Hypoxia-induced pulmonary arterial hypertension augments lung injury and airway reactivity caused by ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Zychowski, Katherine E.; Lucas, Selita N.; Sanchez, Bethany; Herbert, Guy; Campen, Matthew J., E-mail: mcampen@salud.unm.edu

    2016-08-15

    Ozone (O{sub 3})-related cardiorespiratory effects are a growing public health concern. Ground level O{sub 3} can exacerbate pre-existing respiratory conditions; however, research regarding therapeutic interventions to reduce O{sub 3}-induced lung injury is limited. In patients with chronic obstructive pulmonary disease, hypoxia-associated pulmonary hypertension (HPH) is a frequent comorbidity that is difficult to treat clinically, yet associated with increased mortality and frequency of exacerbations. In this study, we hypothesized that established HPH would confer vulnerability to acute O{sub 3} pulmonary toxicity. Additionally, we tested whether improvement of pulmonary endothelial barrier integrity via rho-kinase inhibition could mitigate pulmonary inflammation and injury. To determine if O{sub 3} exacerbated HPH, male C57BL/6 mice were subject to either 3 weeks continuous normoxia (20.9% O{sub 2}) or hypoxia (10.0% O{sub 2}), followed by a 4-h exposure to either 1 ppm O{sub 3} or filtered air (FA). As an additional experimental intervention fasudil (20 mg/kg) was administered intraperitoneally prior to and after O{sub 3} exposures. As expected, hypoxia significantly increased right ventricular pressure and hypertrophy. O{sub 3} exposure in normoxic mice caused lung inflammation but not injury, as indicated by increased cellularity and edema in the lung. However, in hypoxic mice, O{sub 3} exposure led to increased inflammation and edema, along with a profound increase in airway hyperresponsiveness to methacholine. Fasudil administration resulted in reduced O{sub 3}-induced lung injury via the enhancement of pulmonary endothelial barrier integrity. These results indicate that increased pulmonary vascular pressure may enhance lung injury, inflammation and edema when exposed to pollutants, and that enhancement of pulmonary endothelial barrier integrity may alleviate such vulnerability. - Highlights: • Environmental exposures can exacerbate chronic obstructive

  12. Ozone exposure and stomatal sluggishness in different plant physiognomic classes

    Energy Technology Data Exchange (ETDEWEB)

    Paoletti, Elena, E-mail: e.paoletti@ipp.cnr.i [IPP-CNR, Via Madonna del Piano 10, I-50019 Sesto Fiorentino, Florence (Italy); Grulke, Nancy E. [US Forest Service, 4955 Canyon Crest Drive, Riverside, CA 92507 (United States)

    2010-08-15

    Gas exchange responses to static and variable light were tested in three species: snap bean (Phaseolus vulgaris, two cultivars), California black oak (Quercus kelloggii), and blue oak (Q. douglasii). The effects of 1-month (snap beans) and 2-month (oaks) O{sub 3} (ozone) exposure (70 ppb over 8 h per day in open-top chambers) were investigated. A delay in stomatal responses (i.e., 'sluggish' responses) to variable light was found to be both an effect of O{sub 3} exposure and a reason for increased O{sub 3} sensitivity in snap bean cultivars, as it implied higher O{sub 3} uptake during times of disequilibrium. Sluggishness increased the time to open (thus limiting CO{sub 2} uptake) and close stomata (thus increasing transpirational water loss) after abrupt changes in light level. Similar responses were shown by snap beans and oaks, suggesting that O{sub 3}-induced stomatal sluggishness is a common trait among different plant physiognomic classes. - Sluggish stomatal responses are suggested to be both an effect of O{sub 3} exposure and a reason of increased O{sub 3} sensitivity in plants.

  13. Using air quality modeling to study source-receptor relationships between nitrogen oxides emissions and ozone exposures over the United States.

    Science.gov (United States)

    Tong, Daniel Q; Muller, Nicholas Z; Kan, Haidong; Mendelsohn, Robert O

    2009-11-01

    Human exposure to ambient ozone (O(3)) has been linked to a variety of adverse health effects. The ozone level at a location is contributed by local production, regional transport, and background ozone. This study combines detailed emission inventory, air quality modeling, and census data to investigate the source-receptor relationships between nitrogen oxides (NO(x)) emissions and population exposure to ambient O(3) in 48 states over the continental United States. By removing NO(x) emissions from each state one at a time, we calculate the change in O(3) exposures by examining the difference between the base and the sensitivity simulations. Based on the 49 simulations, we construct state-level and census region-level source-receptor matrices describing the relationships among these states/regions. We find that, for 43 receptor states, cumulative NO(x) emissions from upwind states contribute more to O(3) exposures than the state's own emissions. In-state emissions are responsible for less than 15% of O(3) exposures in 90% of U.S. states. A state's NO(x) emissions can influence 2 to 40 downwind states by at least a 0.1 ppbv change in population-averaged O(3) exposure. The results suggest that the U.S. generally needs a regional strategy to effectively reduce O(3) exposures. But the current regional emission control program in the U.S. is a cap-and-trade program that assumes the marginal damage of every ton of NO(x) is equal. In this study, the average O(3) exposures caused by one ton of NO(x) emissions ranges from -2.0 to 2.3 ppm-people-hours depending on the state. The actual damage caused by one ton of NO(x) emissions varies considerably over space.

  14. Maternal exposure to ozone and PM2.5 and the prevalence of orofacial clefts in four U.S. states

    International Nuclear Information System (INIS)

    Zhou, Ying; Gilboa, Suzanne M.; Herdt, Michele L.; Lupo, Philip J.; Flanders, W. Dana; Liu, Yang; Shin, Mikyong; Canfield, Mark A.; Kirby, Russell S.

    2017-01-01

    Background: While there is some evidence that maternal exposure to ambient air pollution is associated with orofacial clefts in offspring, the epidemiologic studies have been largely equivocal. We evaluated whether maternal exposure to elevated county-level ambient fine particulate matter with aerodynamic diameter ≤2.5 µm (PM 2.5 ) and ozone during early gestation was associated with a higher prevalence of orofacial clefts. Methods: Birth data consisting of 4.7 million births from 2001 to 2007 were obtained from National Birth Defects Prevention Network for four states — Arizona, Florida, New York (excluding New York City), and Texas. The air pollution exposure assessment for gestational weeks 5–10 was based on county-level average concentrations of PM 2.5 and ozone data generated using a Bayesian fusion model available through CDC's Environmental Public Health Tracking Network. Two outcomes were analyzed separately: cleft lip with or without cleft palate, cleft palate alone. In logistic regression analyses, we adjusted for factors that were suspected confounders or modifiers of the association between the prevalence of orofacial clefts and air pollution, i.e., infant sex, race-ethnicity, maternal education, smoking status during pregnancy, whether this was mother's first baby, maternal age. Results: Each 10 µg/m 3 increase in PM 2.5 concentration was significantly associated with cleft palate alone (OR =1.43, 95% CI: 1.11–1.86). There was no significant association between PM 2.5 concentration and cleft lip with or without cleft palate. No associations were observed between ozone exposure and the two outcomes of orofacial clefts. Conclusions: Our study suggests that PM 2.5 significantly increased the risk of cleft palate alone, but did not change the incidence of cleft lip with or without palate. Ozone levels did not correlate with incidence of orofacial clefts. - Highlights: • This is a large study with about 4.7 million births and 7000

  15. Suppression and recovery of the alveolar macrophage phagocytic system during continuous exposure to 0. 5 ppm ozone

    Energy Technology Data Exchange (ETDEWEB)

    Gilmour, M.I.; Hmieleski, R.R.; Stafford, E.A.; Jakab, G.J. (Johns Hopkins University, School of Hygiene and Public Health, Baltimore, MD (USA))

    1991-05-01

    Short-term exposures to ozone (O3) are known to impair pulmonary antibacterial defenses and alveolar macrophage (AM) phagocytosis in a dose-related manner. To determine the effect of prolonged O3 exposure, Swiss mice were exposed continuously to 0.5 ppm O3. At 1, 3, 7, and 14 days, intrapulmonary killing was assessed by inhalation challenge with Staphylococcus aureus or Proteus mirabilis and by comparing the number of viable bacteria remaining in the lungs at 4 h between O3-exposed and control animals. To evaluate the effects of O3 on the functional capacity of the AMs, Fc-receptor mediated phagocytosis was assessed. Ozone exposure impaired the intrapulmonary killing of S. aureus at 1 and 3 days; however, with prolonged exposure, the bactericidal capacity of the lungs returned to normal. This trend of an initial suppression followed by recovery was reflected in the phagocytic capacity of the AMs. In contrast to S. aureus, when P. mirabilis was used as the challenge organism, O3 exposure had no suppressive effect on pulmonary bactericidal activity, which correlated with an increase in the phagocytic cell population in the lungs. Morphologic examination of the lavaged macrophages showed that after 1 day of O3 exposure, the AMs were more foamy, and contained significantly more vacuoles. There was also a significant increase in binucleated cells at 3 days. These studies demonstrate that continuous exposure to O3 modulates AM-dependent lung defenses and points to the importance of the challenge organism and exposure protocol in establishing the adverse effect of O3.

  16. Reported Exposure and Emotional Reactivity to Daily Stressors: The Roles of Adult-Age and Global Perceived Stress

    Science.gov (United States)

    Stawski, Robert S.; Sliwinski, Martin J.; Almeida, David M.; Smyth, Joshua M.

    2012-01-01

    A central goal of daily stress research is to identify resilience and vulnerability factors associated with exposure and reactivity to daily stressors. The current study examined how age differences and global perceptions of stress relate to exposure and emotional reactivity to daily stressors. Sixty-seven younger (Mage = 20) and 116 older (Mage = 80) adults completed a daily stress diary and measures of positive and negative affect on 6 days over a 14 day period. Participants also completed a measure of global perceived stress. Results revealed that reported exposure to daily stressors is reduced in old age, but that emotional reactivity to daily stressors did not differ between young and older adults. Global perceived stress was associated with greater reported exposure to daily stressors in old adults, and greater stress-related increases in negative affect in younger adults. Furthermore, across days on which daily stressors were reported, intraindividual variability in the number and severity of stressors reported was associated with increased negative affect, but only among younger adults. PMID:18361654

  17. Reported exposure and emotional reactivity to daily stressors: the roles of adult age and global perceived stress.

    Science.gov (United States)

    Stawski, Robert S; Sliwinski, Martin J; Almeida, David M; Smyth, Joshua M

    2008-03-01

    A central goal of daily stress research is to identify resilience and vulnerability factors associated with exposure and reactivity to daily stressors. The present study examined how age differences and global perceptions of stress relate to exposure and emotional reactivity to daily stressors. Sixty-seven younger (M age = 20) and 116 older (M age = 80) adults completed a daily stress diary and measures of positive and negative affect on 6 days over a 14-day period. Participants also completed a measure of global perceived stress. Results revealed that reported exposure to daily stressors is reduced in old age but that emotional reactivity to daily stressors did not differ between younger and older adults. Global perceived stress was associated with greater reported exposure to daily stressors in older adults and greater stress-related increases in negative affect in younger adults. Furthermore, across days on which daily stressors were reported, intraindividual variability in the number and severity of stressors reported was associated with increased negative affect, but only among younger adults. (c) 2008 APA, all rights reserved.

  18. Ozone, area social conditions, and mortality in Mexico City

    International Nuclear Information System (INIS)

    O'Neill, M.S.; Loomis, Dana; Borja-Aburto, V.H.

    2004-01-01

    We investigated whether the association of daily mortality and ambient ozone differs by age and area social conditions of the region of residence using a time-series analysis. The study setting was metropolitan Mexico City, a high altitude city situated in a valley, with an estimated 20 million inhabitants, large socioeconomic gradients, and ozone levels frequently exceeding international standards. We stratified daily deaths by six census-derived socioeconomic indicators, based on characteristics of the county where decedents lived. We used Poisson regression to model the association between daily mortality and ozone levels (on the day of death and the previous day) in separate models, stratified by area socioeconomic level and age, and controlling for time trends and temperature. Ozone was positively associated with total mortality [0.65% increase per 10 ppb increment, 95% confidence interval (CI): 0.02%, 1.28%] and for mortality among those over age 65 [1.39% increase per 10 ppb increment, 95% CI: 0.51%, 2.28%]. Associations between ozone and all-age mortality did not show any consistent patterns according to socioeconomic gradients. We conclude that elderly people are at higher risk for ozone-associated mortality. Though county-level social indicators in Mexico City were not strong markers of vulnerability to ozone-associated acute mortality in this analysis, complex associations between individual and area-level factors may exist that would require additional data and further analyses to elucidate

  19. Is it true that ozone is always toxic? The end of a dogma

    International Nuclear Information System (INIS)

    Bocci, Velio

    2006-01-01

    There are a number of good experimental studies showing that exposure by inhalation to prolonged tropospheric ozone damages the respiratory system and extrapulmonary organs. The skin, if extensively exposed, may also contribute to the damage. The undoubtful strong reactivity of ozone has contributed to establish the dogma that ozone is always toxic and its medical application must be proscribed. Although it is less known, judiciously practiced ozonetherapy is becoming very useful either on its own or applied in combination with orthodox medicine in a broad range of pathologies. The opponents of ozonetherapy base their judgment on the ozone chemistry, and physicians, without any knowledge of the problem, are often skeptical. During the last 15 years, a clear understanding of the action of ozone in biology and medicine has been gained, allowing today to argue if it is true that ozone is always toxic. The fundamental points that are discussed in this paper are: the topography, anatomical and biochemical characteristics of the organs daily exposed to ozone versus the potent antioxidant capacity of blood exposed to a small and precisely calculated dose of ozone only for a few minutes. It is becoming clear how the respiratory system undergoing a chronic oxidative stress can release slowly, but steadily, a huge amount of toxic compounds able to enter the circulation and cause serious damage. The aim of this paper is to objectively evaluate this controversial issue

  20. Association of short-term exposure to ground-level ozone and respiratory outpatient clinic visits in a rural location – Sublette County, Wyoming, 2008–2011

    Energy Technology Data Exchange (ETDEWEB)

    Pride, Kerry R., E-mail: hgp3@cdc.gov [Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, GA (United States); Wyoming Department of Health, 6101 Yellowstone Road, Suite 510, Cheyenne, WY 82002 (United States); Peel, Jennifer L. [Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523 (United States); Robinson, Byron F. [Scientific Education and Professional Development Program Office, Office of Surveillance, Epidemiology and Laboratory Services, Centers for Disease Control and Prevention, 1600 Clifton Rd, NE, E-92, Atlanta, GA 30333 (United States); Busacker, Ashley [Field Support Branch, Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Wyoming Department of Health, 6101 Yellowstone Road, Suite 510, Cheyenne, WY 82002 (United States); Grandpre, Joseph [Chronic Disease Epidemiologist, Wyoming Department of Health, 6101 Yellowstone Road, Suite 510, Cheyenne, WY 82002 (United States); Bisgard, Kristine M. [Scientific Education and Professional Development Program Office, Office of Surveillance, Epidemiology and Laboratory Services, Centers for Disease Control and Prevention, 600 Clifton Road, NE, E-92, Atlanta, GA 30333 (United States); Yip, Fuyuen Y. [Air Pollution and Respiratory Disease Branch, Centers for Disease Control and Prevention, 600 Clifton Rd, NE, E-92, Atlanta, GA 30333 (United States); Murphy, Tracy D. [Wyoming Department of Health, 101 Yellowstone Road, Suite 510, Cheyenne, WY 82002 (United States)

    2015-02-15

    Objective: Short-term exposure to ground-level ozone has been linked to adverse respiratory and other health effects; previous studies typically have focused on summer ground-level ozone in urban areas. During 2008–2011, Sublette County, Wyoming (population: ~10,000 persons), experienced periods of elevated ground-level ozone concentrations during the winter. This study sought to evaluate the association of daily ground-level ozone concentrations and health clinic visits for respiratory disease in this rural county. Methods: Clinic visits for respiratory disease were ascertained from electronic billing records of the two clinics in Sublette County for January 1, 2008–December 31, 2011. A time-stratified case-crossover design, adjusted for temperature and humidity, was used to investigate associations between ground-level ozone concentrations measured at one station and clinic visits for a respiratory health concern by using an unconstrained distributed lag of 0–3 days and single-day lags of 0 day, 1 day, 2 days, and 3 days. Results: The data set included 12,742 case-days and 43,285 selected control-days. The mean ground-level ozone observed was 47±8 ppb. The unconstrained distributed lag of 0–3 days was consistent with a null association (adjusted odds ratio [aOR]: 1.001; 95% confidence interval [CI]: 0.990–1.012); results for lags 0, 2, and 3 days were consistent with the null. However, the results for lag 1 were indicative of a positive association; for every 10-ppb increase in the 8-h maximum average ground-level ozone, a 3.0% increase in respiratory clinic visits the following day was observed (aOR: 1.031; 95% CI: 0.994–1.069). Season modified the adverse respiratory effects: ground-level ozone was significantly associated with respiratory clinic visits during the winter months. The patterns of results from all sensitivity analyzes were consistent with the a priori model. Conclusions: The results demonstrate an association of increasing ground

  1. Association of short-term exposure to ground-level ozone and respiratory outpatient clinic visits in a rural location – Sublette County, Wyoming, 2008–2011

    International Nuclear Information System (INIS)

    Pride, Kerry R.; Peel, Jennifer L.; Robinson, Byron F.; Busacker, Ashley; Grandpre, Joseph; Bisgard, Kristine M.; Yip, Fuyuen Y.; Murphy, Tracy D.

    2015-01-01

    Objective: Short-term exposure to ground-level ozone has been linked to adverse respiratory and other health effects; previous studies typically have focused on summer ground-level ozone in urban areas. During 2008–2011, Sublette County, Wyoming (population: ~10,000 persons), experienced periods of elevated ground-level ozone concentrations during the winter. This study sought to evaluate the association of daily ground-level ozone concentrations and health clinic visits for respiratory disease in this rural county. Methods: Clinic visits for respiratory disease were ascertained from electronic billing records of the two clinics in Sublette County for January 1, 2008–December 31, 2011. A time-stratified case-crossover design, adjusted for temperature and humidity, was used to investigate associations between ground-level ozone concentrations measured at one station and clinic visits for a respiratory health concern by using an unconstrained distributed lag of 0–3 days and single-day lags of 0 day, 1 day, 2 days, and 3 days. Results: The data set included 12,742 case-days and 43,285 selected control-days. The mean ground-level ozone observed was 47±8 ppb. The unconstrained distributed lag of 0–3 days was consistent with a null association (adjusted odds ratio [aOR]: 1.001; 95% confidence interval [CI]: 0.990–1.012); results for lags 0, 2, and 3 days were consistent with the null. However, the results for lag 1 were indicative of a positive association; for every 10-ppb increase in the 8-h maximum average ground-level ozone, a 3.0% increase in respiratory clinic visits the following day was observed (aOR: 1.031; 95% CI: 0.994–1.069). Season modified the adverse respiratory effects: ground-level ozone was significantly associated with respiratory clinic visits during the winter months. The patterns of results from all sensitivity analyzes were consistent with the a priori model. Conclusions: The results demonstrate an association of increasing ground

  2. Role of surfactant protein-A (SP-A) in lung injury in response to acute ozone exposure of SP-A deficient mice

    International Nuclear Information System (INIS)

    Haque, Rizwanul; Umstead, Todd M.; Ponnuru, Padmavathi; Guo Xiaoxuan; Hawgood, Samuel; Phelps, David S.; Floros, Joanna

    2007-01-01

    Millions are exposed to ozone levels above recommended limits, impairing lung function, causing epithelial damage and inflammation, and predisposing some individuals to pneumonia, asthma, and other lung conditions. Surfactant protein-A (SP-A) plays a role in host defense, the regulation of inflammation, and repair of tissue damage. We tested the hypothesis that the lungs of SP-A(-/-) (KO) mice are more susceptible to ozone-induced damage. We compared the effects of ozone on KO and wild type (WT) mice on the C57BL/6 genetic background by exposing them to 2 parts/million of ozone for 3 or 6 h and sacrificing them 0, 4, and 24 h later. Lungs were subject to bronchoalveolar lavage (BAL) or used to measure endpoints of oxidative stress and inflammation. Despite more total protein in BAL of KO mice after a 3 h ozone exposure, WT mice had increased oxidation of protein and had oxidized SP-A dimers. In KO mice there was epithelial damage as assessed by increased LDH activity and there was increased phospholipid content. In WT mice there were more BAL PMNs and elevated macrophage inflammatory protein (MIP)-2 and monocyte chemoattractant protein (MCP)-1. Changes in MIP-2 and MCP-1 were observed in both KO and WT, however mRNA levels differed. In KO mice MIP-2 mRNA levels changed little with ozone, but in WT levels they were significantly increased. In summary, several aspects of the inflammatory response differ between WT and KO mice. These in vivo findings appear to implicate SP-A in regulating inflammation and limiting epithelial damage in response to ozone exposure

  3. Surface ozone in China: present-day distribution and long-term changes

    Science.gov (United States)

    Xu, X.; Lin, W.; Xu, W.

    2017-12-01

    Reliable knowledge of spatio-temporal variations of surface ozone is highly needed to assess the impacts of ozone on human health, ecosystem and climate. Although regional distributions and trends of surface ozone in European and North American countries have been well characterized, little is known about the variability of surface ozone in many other countries, including China, where emissions of ozone precursors have been changing rapidly in recent decades. Here we present the first comprehensive description of present-day (2013-2017) distribution and long-term changes of surface ozone in mainland China. Recent ozone measurements from China's air quality monitoring network (AQMN) are analyzed to show present-day distributions of a few ozone exposure metrics for urban environment. Long-term measurements of ozone at six background sites, a rural site and an urban are used to study the trends of ozone in background, rural and urban air, respectively. The average levels of ozone at the AQMN sites (mainly urban) are close to those found at many European and North American sites. However, ozone at most of the sites shows very large diurnal and seasonal variations so that ozone nonattainment can occur in many cities, particularly those in the North China Plain (NCP), the south of Northeast China (NEC), the Yangtze River Delta (YRD), the Pearl River Delta (PRD), and the Sichuan Basin-Chongqing region (SCB). In all these regions, particularly in the NCP, the maximum daily 8-h average (MDA8) ozone concentration can significantly exceed the national limit (75 ppb). High annual sum of ozone means over 35 ppb (SOMO35) exist mainly in the NCP, NEC and YRD, with regional averages over 4000 ppb·d. Surface ozone has significantly increased at Waliguan (a baseline site in western China) and Shangdianzi (a background site in the NCP), and decreased in winter and spring at Longfengshan (a background site in Northeast China). No clear trend can be derived from long-term measurements

  4. Establishing a cause and effect relationship for ambient ozone exposure and tree growth in the forest: Progress and an experimental approach

    International Nuclear Information System (INIS)

    Manning, William J.

    2005-01-01

    Much has been written about the effects of ambient ozone on tree growth. Cause and effect has been established with seedlings in chambers. Results from multi-year studies with older tree seedlings, in open-top chambers, have been inconclusive, due to chamber effects. Extrapolation of results from chambers to trees in the forest is not possible. Predictive models for forest tree growth reductions caused by ozone have been developed, but not verified. Dendrochronological methods have been used to establish correlations between radial growth reductions in forest trees and ambient ozone exposure. The protective chemical ethylenediurea (EDU) has been used to protect tree seedlings from ozone injury. An experimental approach is advocated here that utilizes forest trees selected for sensitivity and non-sensitivity to ozone, dendrochronological methods, the protective chemical EDU, and monitoring data for ambient ozone, stomatal conductance, soil moisture potential, air temperature, PAR, etc. in long-term investigations to establish cause and effect relationships. - Progress is reviewed and an experimental approach is proposed to demonstrate a cause and effect relationship for ambient ozone and forest tree growth

  5. Seasonal and diurnal gas exchange differences in ozone-sensitive common milkweed (Asclepias syriaca L.) in relation to ozone uptake

    International Nuclear Information System (INIS)

    Bergweiler, Chris; Manning, William J.; Chevone, Boris I.

    2008-01-01

    Stomatal conductance and net photosynthesis of common milkweed (Asclepias syriaca L.) plants in two different soil moisture regimes were directly quantified and subsequently modeled over an entire growing season. Direct measurements captured the dynamic response of stomatal conductance to changing environmental conditions throughout the day, as well as declining gas exchange and carbon assimilation throughout the growth period beyond an early summer maximum. This phenomenon was observed in plants grown both with and without supplemental soil moisture, the latter of which should theoretically mitigate against harmful physiological effects caused by exposure to ozone. Seasonally declining rates of stomatal conductance were found to be substantial and incorporated into models, making them less susceptible to the overestimations of effective exposure that are an inherent source of error in ozone exposure indices. The species-specific evidence presented here supports the integration of dynamic physiological processes into flux-based modeling approaches for the prediction of ozone injury in vegetation. - Temporal variation in physiological processes underlying diurnal and seasonal ozone uptake are described for a key ozone bioindicator species of North America

  6. Seasonal and diurnal gas exchange differences in ozone-sensitive common milkweed (Asclepias syriaca L.) in relation to ozone uptake

    Energy Technology Data Exchange (ETDEWEB)

    Bergweiler, Chris [Department of Plant, Soil, and Insect Sciences, University of Massachusetts, Amherst, MA 01003 (United States)], E-mail: bergweiler@nre.umass.edu; Manning, William J. [Department of Plant, Soil, and Insect Sciences, University of Massachusetts, Amherst, MA 01003 (United States); Chevone, Boris I. [Department of Plant Pathology, Physiology, and Weed Science, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States)

    2008-03-15

    Stomatal conductance and net photosynthesis of common milkweed (Asclepias syriaca L.) plants in two different soil moisture regimes were directly quantified and subsequently modeled over an entire growing season. Direct measurements captured the dynamic response of stomatal conductance to changing environmental conditions throughout the day, as well as declining gas exchange and carbon assimilation throughout the growth period beyond an early summer maximum. This phenomenon was observed in plants grown both with and without supplemental soil moisture, the latter of which should theoretically mitigate against harmful physiological effects caused by exposure to ozone. Seasonally declining rates of stomatal conductance were found to be substantial and incorporated into models, making them less susceptible to the overestimations of effective exposure that are an inherent source of error in ozone exposure indices. The species-specific evidence presented here supports the integration of dynamic physiological processes into flux-based modeling approaches for the prediction of ozone injury in vegetation. - Temporal variation in physiological processes underlying diurnal and seasonal ozone uptake are described for a key ozone bioindicator species of North America.

  7. Pre-exposure to nitric oxide modulates the effect of ozone on oxidative defenses and volatile emissions in lima bean

    International Nuclear Information System (INIS)

    Souza, Silvia R.; Blande, James D.; Holopainen, Jarmo K.

    2013-01-01

    The roles that ozone and nitric oxide (NO), the chief O 3 precursor, play in the antioxidative balance and inducible volatile emissions of lima bean were assessed. Exposure to O 3 inhibited APX, CAT, and GR, decreased GSH content and induced emissions of (E)-β-ocimene, limonene, 1,8-cineole, linalool, (E)-4,8-dimethyl-1,3,7-nonatriene (E)-DMNT, 2-butanone and nonanal. O 3 did not induce emissions of (E)-β-caryophyllene and appeared to reduce the antioxidative capacity of plants to a greater extent than NO and NO followed by O 3 (NO/O 3 ) treatments. There were significant differences in emissions of (E)-β-ocimene and linalool between NO/O 3 treated plants and controls, but no differences in antioxidant concentrations. A model to explain the relationships between the ascorbate–glutathione cycle and O 3 and NO inducible volatiles was proposed. Our findings suggest that prior exposure to NO modulates the oxidative effect of ozone by the process of cross-tolerance, which might regulate the antioxidative system and induction of volatile organic compounds. -- Highlights: •NO and O 3 disturb antioxidant defenses and cause lipid peroxidation in lima bean plants. •Exposure to NO before exposure to O 3 does not alter the antioxidant defenses and malondialdehyde levels. •The total sum of induced volatiles is reduced in plants that are exposed to NO and then O 3 . •The antioxidant system and induced VOC emission were balanced by pre-exposure to NO before O 3 . -- Capsule: Nitric oxide modulates the ozone-induced oxidative stress in lima bean by cross-tolerance effect

  8. Interaction of ozone with plastic and metallic materials in a dynamic flow system

    Energy Technology Data Exchange (ETDEWEB)

    Altshuller, A P; Wartburg, A F

    1961-01-01

    The loss of ozone in the p.p.h.m. range after passing through or over various plastic and metallic substances has been investigated. The materials used include Teflon, glass, stainless steel, aluminium, polyethylene and polyvinyl tubing, Mylar film, and aluminium foil. Unused Teflon passes ozone without loss. Glass tubing, after a short exposure to ozone, passes ozone without loss. Stainless steel tubing, aluminum tubing or foil and Mylar film must be exposed to ozone in the p.p.h.m. range for several hours before 90% or more of the ozone initially present can be passed through or over these materials. More rapid conditioning to ozone can be achieved by several five to fifteen-minute exposures to about 10 p.p.m. of ozone. Polyethylene and Nalgon tubing even after many hours of exposure to ozone will pass only 75 to 80% of the ozone initially present in the gas stream. Some types of polyvinyl tubing are unsatisfactory for use with ozone irrespective of the amount of exposure to ozone. Flowrates below 1000 c/sup 3//min. will increase losses of ozone. Except for Teflon and glass, materials should not be used in ozone analysis under any circumstances at low flowrates until they are thoroughly conditioned. Results obtained with stainless steel, aluminium and polyethylene indicate that conditioning to ozone once obtained will persist for at least two weeks.

  9. Effect of solar radiation on surface ozone in Cairo

    Energy Technology Data Exchange (ETDEWEB)

    Rizk, H F.S. [National Research Centre, Air Pollution Research Dept., Cairo (Egypt)

    1992-04-01

    Measurements of surface ozone content over an urban area in Cairo were conducted during a year, May 1989 to April 1990, while solar radiation at the same area was measured. Low and high concentrations of ozone are compared with those recommended by the WHO expert committee regarding the daily cycle of ozone concentration. 15 refs.

  10. Ozone distribution in remote ecologically vulnerable terrain of the southern Sierra Nevada, CA

    International Nuclear Information System (INIS)

    Panek, Jeanne; Saah, David; Esperanza, Annie; Bytnerowicz, Andrzej; Fraczek, Witold; Cisneros, Ricardo

    2013-01-01

    Ozone concentration spatial patterns remain largely uncharacterized across the extensive wilderness areas of the Sierra Nevada, CA, despite being downwind of major pollution sources. These natural areas, including four national parks and four national forests, contain forest species that are susceptible to ozone injury. Forests stressed by ozone are also more vulnerable to other agents of mortality, including insects, pathogens, climate change, and ultimately fire. Here we analyze three years of passive ozone monitor data from the southern Sierra Nevada and interpolate landscape-scale spatial and temporal patterns during the summer-through-fall high ozone concentration period. Segmentation analysis revealed three types of ozone exposure sub-regions: high, low, and variable. Consistently high ozone exposure regions are expected to be most vulnerable to forest mortality. One high exposure sub-region has been documented elsewhere as being further vulnerable to increased drought and fire potential. Identifying such hot-spots of forest vulnerability has utility for prioritizing management. -- Highlights: •Three years of passive ozone sampler data over 49,000 km 2 were analyzed spatially. •Spatial and temporal ozone patterns were mapped across the Sierra Nevada, CA. •Sub-regions of consistently high, low and variable ozone exposure were identified. •The 1700–2400 m elevation band delineated a distinct break in ozone concentration. •This approach has utility for prioritizing management across vulnerable landscapes. -- A passive ozone sampler network in combination with spatial analysis techniques was used to characterize landscape-scale ozone patterns and dynamics, identifying regions of consistently high and low ozone exposure for forest management prioritization

  11. Ozone killing action against bacterial and fungal species; microbiological testing of a domestic ozone generator.

    Science.gov (United States)

    Dyas, A; Boughton, B J; Das, B C

    1983-10-01

    The action of ozone generated from a small domestic device was examined with a view to using it in clinical isolation units accommodating immunosuppressed patients. Over a six-hour period in an average size room the device did not generate sufficient ozone to suppress bacterial and fungal growth. A useful bactericidal action, against a variety of human pathogens was achieved with ozone concentrations between 0.3 to 0.9 ppm. Bactericidal ozone concentrations are close to the limit permitted for human exposure however and further experiments are indicated.

  12. Climate Prediction Center (CPC)Stratospheric Monitoring Ozone Blended Analysis

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 3-D global ozone mixing ratio (ppm) and total column ozone (DU) dataset analyzed from daily Solar Backscatter Ultraviolet Instrument(SBUV/2) and TIROS Operational...

  13. Maternal exposure to ozone and PM{sub 2.5} and the prevalence of orofacial clefts in four U.S. states

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Ying, E-mail: yzhou2@cdc.gov [Environmental Health Tracking Branch, Division of Environmental Hazards and Health Effects, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA (United States); Gilboa, Suzanne M. [Birth Defects Branch, Division of Congenital and Developmental Disorders, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, GA (United States); Herdt, Michele L. [New York State Department of Health, Center for Environmental Health, Albany, NY (United States); State University of New York at Albany, Department of Epidemiology and Biostatistics, Rensselaer, NY (United States); Lupo, Philip J. [Baylor College of Medicine, Department of Pediatrics, Section of Hematology-Oncology, Houston, TX (United States); Flanders, W. Dana [Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA (United States); Liu, Yang [Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA (United States); Shin, Mikyong [Environmental Health Tracking Branch, Division of Environmental Hazards and Health Effects, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA (United States); Canfield, Mark A. [Birth Defects Epidemiology and Surveillance Branch, Texas Department of State Health Services, Austin, TX (United States); Kirby, Russell S. [Department of Community and Family Health, College of Public Health, University of South Florida, Tampa, FL (United States)

    2017-02-15

    Background: While there is some evidence that maternal exposure to ambient air pollution is associated with orofacial clefts in offspring, the epidemiologic studies have been largely equivocal. We evaluated whether maternal exposure to elevated county-level ambient fine particulate matter with aerodynamic diameter ≤2.5 µm (PM{sub 2.5}) and ozone during early gestation was associated with a higher prevalence of orofacial clefts. Methods: Birth data consisting of 4.7 million births from 2001 to 2007 were obtained from National Birth Defects Prevention Network for four states — Arizona, Florida, New York (excluding New York City), and Texas. The air pollution exposure assessment for gestational weeks 5–10 was based on county-level average concentrations of PM{sub 2.5} and ozone data generated using a Bayesian fusion model available through CDC's Environmental Public Health Tracking Network. Two outcomes were analyzed separately: cleft lip with or without cleft palate, cleft palate alone. In logistic regression analyses, we adjusted for factors that were suspected confounders or modifiers of the association between the prevalence of orofacial clefts and air pollution, i.e., infant sex, race-ethnicity, maternal education, smoking status during pregnancy, whether this was mother's first baby, maternal age. Results: Each 10 µg/m{sup 3} increase in PM{sub 2.5} concentration was significantly associated with cleft palate alone (OR =1.43, 95% CI: 1.11–1.86). There was no significant association between PM{sub 2.5} concentration and cleft lip with or without cleft palate. No associations were observed between ozone exposure and the two outcomes of orofacial clefts. Conclusions: Our study suggests that PM{sub 2.5} significantly increased the risk of cleft palate alone, but did not change the incidence of cleft lip with or without palate. Ozone levels did not correlate with incidence of orofacial clefts. - Highlights: • This is a large study with about 4

  14. Growth response of seedlings of six Betula pubescens Ehrh. provenances to six ozone exposure regimes

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, L.M. [Agricultural Univ. of Norway, Aas (Norway). Dept. of Horticulture and Crop Science

    1998-07-01

    Seedlings of six provenances of Betula pubescens Ehrh. from different latitudes (59-70 deg N) were grown under six ozone exposure regimes by combining different concentrations and daily exposure periods. The different treatments at increasing O{sub 3} exposure over 40 nmol/mol (AOT40 given in parentheses) were: 19 nmol mol{sup -1}/24 h day{sup -1} (0.1 {mu}mol/mol-h), 42 nmol mol{sup -1}/12 h day{sup -1} (2.5 {mu}mol/mol-h), 44 nmol mol{sup -1}/24 h day{sup -1} (7.1 {mu}mol/mol-h), 76 nmol mol{sup -1}/6 day{sup -1} (9.4 {mu}mol/mol-h), 75 nmol mol{sup -1}/12 h day{sup -1} (17.8 {mu}mol/mol{sup -1}) and 116 nmol mol{sup -1}/6 h day{sup -1} (19.8 {mu}mol/mol{sup -1}) for 40 days at a 24 h day{sup -1} photoperiod in growth chambers placed in a greenhouse. The effect of increasing the O{sub 3} exposure from 19 nmol mol{sup -1}/24 h to 42 nmol mol{sup -1}/12 h was a decrease in root but not shoot dry weight. A further increase in the exposure to 44 nmol mol{sup -1}/24 h also decreased the shoot dry weight. An increase in the O{sub 3} concentration to 75 and 116 nmol mol{sup -1} further decreased shoot and root dry weights. A moderate O{sub 3} exposure (42 nmol mol{sup -1}/12 h) increased the plant height and leaf size, while a further increase in O{sub 3} concentration and exposure time decreased both of these variables. The birch provenances generally had a similar response to the O{sub 3} treatments. The accumulated O{sub 3} exposure over the 0, 10, 20, 30, 40 and 50 nmol mol{sup -1} concentrations (AOT0, AOT10, AOT20, AOT30, AOT40 and AOT50, respectively) was calculated for all O{sub 3} treatments. The shoot and root dry weights were correlated best with AOT40 and AOT30, and were estimated to decrease by 10% at an AOT40 of 7.0 and 5.5 {mu}mol mol{sup -1}-h, respectively. The development of O{sub 3} injury (yellow stipples/chlorosis) was most marked when correlated with AOT40 26 refs, 6 figs, 1 tab

  15. Synoptic and meteorological drivers of extreme ozone concentrations over Europe

    Science.gov (United States)

    Otero, Noelia Felipe; Sillmann, Jana; Schnell, Jordan L.; Rust, Henning W.; Butler, Tim

    2016-04-01

    The present work assesses the relationship between local and synoptic meteorological conditions and surface ozone concentration over Europe in spring and summer months, during the period 1998-2012 using a new interpolated data set of observed surface ozone concentrations over the European domain. Along with local meteorological conditions, the influence of large-scale atmospheric circulation on surface ozone is addressed through a set of airflow indices computed with a novel implementation of a grid-by-grid weather type classification across Europe. Drivers of surface ozone over the full distribution of maximum daily 8-hour average values are investigated, along with drivers of the extreme high percentiles and exceedances or air quality guideline thresholds. Three different regression techniques are applied: multiple linear regression to assess the drivers of maximum daily ozone, logistic regression to assess the probability of threshold exceedances and quantile regression to estimate the meteorological influence on extreme values, as represented by the 95th percentile. The relative importance of the input parameters (predictors) is assessed by a backward stepwise regression procedure that allows the identification of the most important predictors in each model. Spatial patterns of model performance exhibit distinct variations between regions. The inclusion of the ozone persistence is particularly relevant over Southern Europe. In general, the best model performance is found over Central Europe, where the maximum temperature plays an important role as a driver of maximum daily ozone as well as its extreme values, especially during warmer months.

  16. Pulmonary arachidonic acid metabolism following acute exposures to ozone and nitrogen dioxide

    International Nuclear Information System (INIS)

    Schlesinger, R.B.; Driscoll, K.E.; Gunnison, A.F.; Zelikoff, J.T.

    1990-01-01

    Ozone (O 3 ) and nitrogen dioxide (NO 2 ) are common air pollutants, and exposure to these gases has been shown to affect pulmonary physiology, biochemistry, and structure. This study examined their ability to modulate arachidonic acid metabolites (eicosanoids) in the lungs. Rabbits were exposed for 2 h to O 3 at 0.1, 0.3, or 1 ppm; NO 2 at 1, 3, or 10 ppm; or to a mixture of 0.3 ppm O 3 and 3 ppm NO 2 . Groups of animals sacrificed either immediately or 24 h after each exposure underwent broncho-pulmonary lavage. Selected eicosanoids were assessed in lavage fluid by radioimmunoassay. Increases in prostaglandins E2 (PGE2) and F2 alpha (PGF2 alpha) were found immediately after exposure to 1 ppm O 3 . Exposure to 10 ppm NO 2 resulted in a depression of 6-keto-PGF1 alpha, while thromboxane B2 (TxB2) was elevated after exposure to 1 ppm NO 2 and depressed following 3 and 10 ppm. The O 3 /NO 2 mixture resulted in synergistic increases in PGE2 and PGF2 alpha, with the response appearing to be driven by O 3 . This study has demonstrated that acute exposure to either O 3 or NO 2 can alter pulmonary arachidonic acid metabolism and that the responses to these oxidants differ, both quantitatively and qualitatively

  17. Ozone health effects

    International Nuclear Information System (INIS)

    Easterly, C.

    1994-01-01

    Ozone is a principal component of photochemical air pollution endogenous to numerous metropolitan areas. It is primarily formed by the oxidation of NOx in the presence of sunlight and reactive organic compounds. Ozone is a highly active oxidizing agent capable of causing injury to the lung. Lung injury may take the form of irritant effects on the respiratory tract that impair pulmonary function and result in subjective symptoms of respiratory discomfort. These symptoms include, but are not limited to, cough and shortness of breath, and they can limit exercise performance. The effects of ozone observed in humans have been primarily limited to alterations in respiratory function, and a range of respiratory physiological parameters have been measured as a function of ozone exposure in adults and children. These affects have been observed under widely varying (clinical experimental and environmental settings) conditions

  18. Reported Exposure and Emotional Reactivity to Daily Stressors: The Roles of Adult-Age and Global Perceived Stress

    OpenAIRE

    Stawski, Robert S.; Sliwinski, Martin J.; Almeida, David M.; Smyth, Joshua M.

    2008-01-01

    A central goal of daily stress research is to identify resilience and vulnerability factors associated with exposure and reactivity to daily stressors. The current study examined how age differences and global perceptions of stress relate to exposure and emotional reactivity to daily stressors. Sixty-seven younger (Mage = 20) and 116 older (Mage = 80) adults completed a daily stress diary and measures of positive and negative affect on 6 days over a 14 day period. Participants also completed ...

  19. Effect of ozone and histamine on airway permeability to horseradish peroxidase in guinea pigs

    International Nuclear Information System (INIS)

    Miller, P.D.; Gordon, T.; Warnick, M.; Amdur, M.O.

    1986-01-01

    Airway permeability was studied in groups of male guinea pigs at 2, 8, and 24 h after a 1-h exposure to 1 ppm ozone or at 2 h after a 1-h exposure to filtered air (control). Intratracheal administration of 2 mg horseradish peroxidase (HRP) was followed by blood sampling at 5-min intervals up to 30 min. The rate of appearance of HRP in plasma was significantly higher at 2 and 8 h after ozone exposure than that found in animals examined 2 h after air exposure or 24 h after ozone exposure. A dose of 0.12 mg/kg of subcutaneous histamine given after the 15 min blood sample significantly increased the already elevated permeability seen at 2 h post ozone, but had no effect on animals exposed to filtered air 2 h earlier or to ozone 24 h earlier. No difference was seen in the amount of subcutaneous radiolabeled histamine in the lungs of animals exposed 2 h earlier either to air or to ozone. These data indicate that a short-term exposure to ozone produced a reversible increase in respiratory epithelial permeability to HRP in guinea pigs. The potentiation of this increased permeability by histamine may be another manifestation of ozone-induced hyperreactivity

  20. Surface ozone concentrations in Europe: Links with the regional-scale atmospheric circulation

    Science.gov (United States)

    Davies, T. D.; Kelly, P. M.; Low, P. S.; Pierce, C. E.

    1992-06-01

    Daily surface ozone observations from 1978 (1976 for some analyses) to 1988 for Bottesford (United Kingdom), Cabauw, Kloosterburen (The Netherlands), Hohenpeissenberg, Neuglobsow, Hamburg, and Arkona (Germany) are used to analyze links between surface ozone variations and the atmospheric circulation. A daily Europe-wide synoptic classification highlights marked differences between surface ozone/meteorology relationships in summer and winter. These relationships are characterized by correlations between daily surface ozone concentrations at each station and a local subregional surface pressure gradient (a wind speed index). Although there are geographical variations, which are explicable in terms of regional climatology, there are distinct annual cycles. In summer, the surface ozone/wind speed relationship exhibits the expected negative sign; however, in winter, the relationship is, in the main, strongly positive, especially at those stations which are more influenced by the vigorous westerlies. Spring and autumn exhibit negative, positive, or transitional (between summer and winter) behavior, depending on geographical position. It is suggested that these relationships reflect the importance of vertical exchange from the free troposphere to the surface in the nonsummer months. Composite surface pressure patterns and surface pressure anomaly (from the long-term mean) patterns associated with high surface ozone concentrations on daily and seasonal time scales are consistent with the surface ozone/wind speed relationships. Moreover, they demonstrate that high surface ozone concentrations, in a climatological time frame, can be associated with mean surface pressure patterns which have a synoptic reality and are robust. Such an approach may be useful in interpreting past variations in surface ozone and may help to isolate the effect of human activity. It is also possible that assessments can be made of the effect of projected future changes in the atmospheric circulation

  1. Exposure- and flux-based assessment of ozone risk to sugarcane plants

    Science.gov (United States)

    Moura, Bárbara Baêsso; Hoshika, Yasutomo; Ribeiro, Rafael Vasconcelos; Paoletti, Elena

    2018-03-01

    Ozone (O3) is a toxic oxidative air pollutant, with significant detrimental effects on crops. Sugarcane (Saccharum spp.) is an important crop with no O3 risk assessment performed so far. This study aimed to assess O3 risk to sugarcane plants by using exposure-based indices (AOT40 and W126) based on O3 concentrations in the air, and the flux-based index (PODy, where y is a threshold of uptake) that considers leaf O3 uptake and the influence of environmental conditions on stomatal conductance (gsto). Two sugarcane genotypes (IACSP94-2094 and IACSP95-5000) were subjected to a 90-day Free-Air Controlled Experiment (FACE) exposure at three levels of O3 concentrations: ambient (Amb); Amb x1.2; and Amb x1.4. Total above-ground biomass (AGB), stalk biomass (SB) and leaf biomass (LB) were evaluated and the potential biomass production in a clean air was estimated by assuming a theoretical clean atmosphere at 10 ppb as 24 h O3 average. The Jarvis-type multiplicative algorithm was used to parametrize gsto including environmental factors i.e. air temperature, light intensity, air vapor pressure deficit, and minimum night-time temperature. Ozone exposure caused a negative impact on AGB, SB and LB. The O3 sensitivity of sugarcane may be related to its high gsto (∼535 mmol H2O m-2 s-1). As sugarcane is adapted to hot climate conditions, gsto was restricted when the current minimum air temperature (Tmin) was below ∼14 °C and the minimum night-time air temperature of the previous day (Tnmin) was below ∼7.5 °C. The flux-based index (PODy) performed better than the exposure-based indices in estimating O3 effect on biomass losses. We recommend a y threshold of 2 nmol m-2 s-1 to incorporate O3 effects on both AGB and SB and 1 nmol m-2 s-1 on LB. In order not to exceed 4% reduction in the growth of these two sugarcane genotypes, we recommend the following critical levels: 1.09 and 1.04 mmol m-2 POD2 for AGB, 0.91 and 0.96 mmol m-2 POD2 for SB, and 3.00 and 2.36 mmol m-2 POD1 for

  2. Ozone decomposition kinetics on alumina: effects of ozone partial pressure, relative humidity and repeated oxidation cycles

    Directory of Open Access Journals (Sweden)

    R. C. Sullivan

    2004-01-01

    Full Text Available The room temperature kinetics of gas-phase ozone loss via heterogeneous interactions with thin alumina films has been studied in real-time using 254nm absorption spectroscopy to monitor ozone concentrations. The films were prepared from dispersions of fine alumina powder in methanol and their surface areas were determined by an in situ procedure using adsorption of krypton at 77K. The alumina was found to lose reactivity with increasing ozone exposure. However, some of the lost reactivity could be recovered over timescales of days in an environment free of water, ozone and carbon dioxide. From multiple exposures of ozone to the same film, it was found that the number of active sites is large, greater than 1.4x1014 active sites per cm2 of surface area or comparable to the total number of surface sites. The films maintain some reactivity at this point, which is consistent with there being some degree of active site regeneration during the experiment and with ozone loss being catalytic to some degree. The initial uptake coefficients on fresh films were found to be inversely dependent on the ozone concentration, varying from roughly 10-6 for ozone concentrations of 1014 molecules/cm3 to 10-5 at 1013 molecules/cm3. The initial uptake coefficients were not dependent on the relative humidity, up to 75%, within the precision of the experiment. The reaction mechanism is discussed, as well as the implications these results have for assessing the effect of mineral dust on atmospheric oxidant levels.

  3. Seasonal differences and within-canopy variations of antioxidants in mature spruce (Picea abies) trees under elevated ozone in a free-air exposure system

    International Nuclear Information System (INIS)

    Hofer, Nora; Alexou, Maria; Heerdt, Christian; Loew, Markus; Werner, Herbert; Matyssek, Rainer; Rennenberg, Heinz; Haberer, Kristine

    2008-01-01

    The effect of free-air ozone fumigation and crown position on antioxidants were determined in old-growth spruce (Picea abies) trees in the seasonal course of two consecutive years (2003 and 2004). Levels of total ascorbate and its redox state in the apoplastic washing fluid (AWF) were increased under double ambient ozone concentrations (2 x O 3 ), whilst ascorbate concentrations in needle extracts were unchanged. Concentrations of apoplastic and symplastic ascorbate were significantly higher in 2003 compared to 2004 indicating a combined effect of the drought conditions in 2003 with enhanced ozone exposure. Elevated ozone had only weak effects on total glutathione levels in needle extracts, phloem exudates and xylem saps. Total and oxidised glutathione concentrations were higher in 2004 compared to 2003 and seemed to be more affected by enhanced ozone influx in the more humid year 2004 compared to the combined effect of elevated ozone and drought in 2003 as observed for ascorbate. - Antioxidant defence in sun and shade needles of Picea abies under free-air ozone fumigation in the seasonal course of two consecutive years

  4. Contribution of various microenvironments to the daily personal exposure to ultrafine particles: Personal monitoring coupled with GPS tracking

    Science.gov (United States)

    Bekö, Gabriel; Kjeldsen, Birthe Uldahl; Olsen, Yulia; Schipperijn, Jasper; Wierzbicka, Aneta; Karottki, Dorina Gabriela; Toftum, Jørn; Loft, Steffen; Clausen, Geo

    2015-06-01

    Exposure to ultrafine particles (UFP) may have adverse health effects. Central monitoring stations do not represent the personal exposure to UFP accurately. Few studies have previously focused on personal exposure to UFP. Sixty non-smoking residents living in Copenhagen, Denmark were asked to carry a backpack equipped with a portable monitor, continuously recording particle number concentrations (PN), in order to measure the real-time individual exposure over a period of ˜48 h. A GPS logger was carried along with the particle monitor and allowed us to estimate the contribution of UFP exposure occurring in various microenvironments (residence, during active and passive transport, other indoor and outdoor environments) to the total daily exposure. On average, the fractional contribution of each microenvironment to the daily integrated personal exposure roughly corresponded to the fractions of the day the subjects spent in each microenvironment. The home environment accounted for 50% of the daily personal exposure. Indoor environments other than home or vehicles contributed with ˜40%. The highest median UFP concentration was obtained during passive transport (vehicles). However, being in transit or outdoors contributed 5% or less to the daily exposure. Additionally, the subjects recorded in a diary the periods when they were at home. With this approach, 66% of the total daily exposure was attributable to the home environment. The subjects spent 28% more time at home according to the diary, compared to the GPS. These results may indicate limitations of using diaries, but also possible inaccuracy and miss-classification in the GPS data.

  5. Impacts of ozone on trees and crops

    International Nuclear Information System (INIS)

    Felzer, B.S.; Cronina, T.; Melillo, J.M.; Reilly, J.M.; Xiaodong, Wang

    2007-01-01

    In this review article, we explore how surface-level ozone affects trees and crops with special emphasis on consequences for productivity and carbon sequestration. Vegetation exposure to ozone reduces photosynthesis, growth, and other plant functions. Ozone formation in the atmosphere is a product of NO x , which are also a source of nitrogen deposition. Reduced carbon sequestration of temperate forests resulting from ozone is likely offset by increased carbon sequestration from nitrogen fertilization. However, since fertilized crop-lands are generally not nitrogen-limited, capping ozone-polluting substances in the USA, Europe, and China can reduce future crop yield loss substantially. (authors)

  6. Comparing Model Ozone Loss during the SOLVE and SOLVE-2 Winters

    Science.gov (United States)

    Drdla, K.

    2003-01-01

    Model simulations have been used to analyze the factors influencing ozone loss during the 1999-2000 and 2002-2003 js. For both winters, the evolution of the Arctic vortex from November to April has been simulated using a trajectory-based microphysical and photochemical model. Extensive PSC formation and strong ozone depletion are evident in both winters. However, the ozone loss begins earlier in the 2002-2003 winter, with significant ozone depletion by early January. Analysis of the model results shows that during December 2002 not only cold temperatures but also the vortex structure was critical, allowing PSC-processed air parcels to experience significant solar exposure. The resultant ozone loss can be differentiated from ozone loss that occurs in the springtime, in particular because of the continued exposure to PSCs. For example, chlorine reactivation by the PSCs causes ozone loss to be insensitive to denitrification. Therefore, diagnosing the extent of ozone loss early in the winter is critical In understanding the overall winter-long ozone depletion.

  7. Relative impacts of worldwide tropospheric ozone changes and regional emission modifications on European surface-ozone levels

    International Nuclear Information System (INIS)

    Szopa, S.; Hauglustaine, D.A.

    2007-01-01

    Multi-scale models were applied to assess the surface ozone changes in 2030. Several emission scenarios are considered, ranging from (a) a pessimistic anthropogenic emission increase to (b) an optimistic decrease of emissions, and including (c) a realistic scenario that assumes the implementation of control legislations [CLE]. The two extreme scenarios lead respectively to homogeneous global increase and decrease of surface ozone, whereas low and inhomogeneous changes associated with a slight global increase of ozone are found for the CLE scenario. Over western Europe, for the CLE scenario, the benefit of European emission reduction is significantly counterbalanced by increasing global ozone levels. Considering warmer conditions over Europe and future emission modifications, the human health exposure to surface ozone is found to be significantly worsened. (authors)

  8. The Relationship Between Digital Technology Experience, Daily Media Exposure and Working Memory Capacity

    Directory of Open Access Journals (Sweden)

    Muhterem DİNDAR

    2016-06-01

    Full Text Available Today’s youngsters interact with digital technologies to a great extent which leads scholars to question the influence of this exposure on human cognitive structure. Through resorting to digital nativity assumptions, it is presumed that cognitive architecture of the youth may change in accordance with digital technology use. In this regard, the current study investigated the relationship between digital technology experience, daily media exposure and working memory capacity of so-called digital native participants. A total of 572 undergraduate students responded to self-report measures, which addressed years of experience for 7 different digital devices and the daily time spent for 14 different digital activities. Participants’ working memory capacity was measured through the Computation Span and the Dot Matrix Test. While the former was used to measure the phonological loop capacity, the latter was used to address the visuo-spatial sketchpad capacity. Correlational analyses revealed that neither the phonological loop capacity nor the visuo-spatial sketchpad capacity was related to digital technology experience and daily media exposure. Thus, the transformative contribution of digital technology experience to human cognitive architecture could not be observed through the current measures

  9. Effect of daily noise exposure monitoring on annual rates of hearing loss in industrial workers.

    Science.gov (United States)

    Rabinowitz, Peter M; Galusha, Deron; Kirsche, Sharon R; Cullen, Mark R; Slade, Martin D; Dixon-Ernst, Christine

    2011-06-01

    Occupational noise-induced hearing loss (NIHL) is prevalent, yet evidence on the effectiveness of preventive interventions is lacking. The effectiveness of a new technology allowing workers to monitor daily at-ear noise exposure was analysed. Workers in the hearing conservation program of an aluminium smelter were recruited because of accelerated rates of hearing loss. The intervention consisted of daily monitoring of at-ear noise exposure and regular feedback on exposures from supervisors. The annual rate of change in high frequency hearing average at 2, 3 and 4 KHz before intervention (2000-2004) and 4 years after intervention (2006-2009) was determined. Annual rates of loss were compared between 78 intervention subjects and 234 controls in other company smelters matched for age, gender and high frequency hearing threshold level in 2005. Individuals monitoring daily noise exposure experienced on average no further worsening of high frequency hearing (average rate of hearing change at 2, 3 and 4 KHz = -0.5 dB/year). Matched controls also showed decelerating hearing loss, the difference in rates between the two groups being significant (p hearing loss showed a similar trend but the difference was not statistically significant (p = 0.06). Monitoring daily occupational noise exposure inside hearing protection with ongoing administrative feedback apparently reduces the risk of occupational NIHL in industrial workers. Longer follow-up of these workers will help determine the significance of the intervention effect. Intervention studies for the prevention of NIHL need to include appropriate control groups.

  10. Adjuvant combined ozone therapy for extensive wound over tibia

    Directory of Open Access Journals (Sweden)

    Prasham Shah

    2011-01-01

    Full Text Available Disinfectant and antibacterial properties of ozone are utilized in the treatment of nonhealing or ischemic wounds. We present here a case of 59 years old woman with compartment syndrome following surgical treatment of stress fracture of proximal tibia with extensively infected wound and exposed tibia to about 4/5 of its extent. The knee joint was also infected with active pus draining from a medial wound. At presentation the patient had already taken treatment for 15 days in the form of repeated wound debridements and parenteral antibiotics, which failed to heal the wound and she was advised amputation. Topical ozone therapy twice daily and ozone autohemotherapy once daily were given to the patient along with daily dressings and parenteral antibiotics. Within 5 days, the wound was healthy enough for spilt thickness skin graft to provide biological dressing to the exposed tibia bone. Topical ozone therapy was continued for further 5 days till the knee wound healed. On the 15th day, implant removal, intramedullary nailing, and latissimus dorsi pedicle flap were performed. Both the bone and the soft tissue healed without further complications and at 20 months follow-up, the patient was walking independently with minimal disability.

  11. Profiling secondary metabolites of needles of ozone-fumigated white pine (Pinus strobus) clones by thermally assisted hydrolysis/methylation GC/MS.

    Science.gov (United States)

    Shadkami, F; Helleur, R J; Cox, R M

    2007-07-01

    Plant secondary metabolites have an important role in defense responses against herbivores and pathogens, and as a chemical barrier to elevated levels of harmful air pollutants. This study involves the rapid chemical profiling of phenolic and diterpene resin acids in needles of two (ozone-tolerant and ozone-sensitive) white pine (Pinus strobus) clones, fumigated with different ozone levels (control, and daily events peaking at 80 and 200 ppb) for 40 days. The phenolic and resin acids were measured using thermally assisted hydrolysis and methylation (THM) gas chromatography/mass spectrometry. Short-term fumigation affected the levels of two phenolic acids, i.e., 3-hydroxybenzoic and 3,4-dihydroxybenzoic acids, in that both showed a substantial decrease in concentration with increased ozone dose. The decrease in concentration of these THM products may be caused by inhibition of the plant's shikimate biochemical pathway caused by ozone exposure. The combined occurrence of these two ozone-sensitive indicators has a role in biomonitoring of ozone levels and its impact on forest productivity. In addition, chromatographic profile differences in the major diterpene resin acid components were observed between ozone-tolerant and ozone-sensitive clones. The resin acids anticopalic, 3-oxoanticopalic, 3beta-hydroxyanticopalic, and 3,4-cycloanticopalic acids were present in the ozone-sensitive pine; however, only anticopalic acid was present in the ozone-tolerant clone. This phenotypic variation in resin acid composition may be useful in distinguishing populations that are differentially adapted to air pollutants.

  12. Ozone uptake (flux) as it relates to ozone-induced foliar symptoms of Prunus serotina and Populus maximowizii x trichocarpa

    International Nuclear Information System (INIS)

    Orendovici-Best, T.; Skelly, J.M.; Davis, D.D.; Ferdinand, J.A.; Savage, J.E.; Stevenson, R.E.

    2008-01-01

    Field studies were conducted during 2003 and 2004 from early June to the end of August, at 20 sites of lower or higher elevation within north-central Pennsylvania, using seedlings of black cherry (Prunus serotina, Ehrh.) and ramets of hybrid poplar (Populus maximowizii x trichocarpa). A linear model was developed to estimate the influence of local environmental conditions on stomatal conductance. The most significant factors explaining stomatal variance were tree species, air temperature, leaf vapor pressure deficit, elevation, and time of day. Overall, environmental factors explained less than 35% of the variation in stomatal conductance. Ozone did not affect gas exchange rates in either poplar or cherry. Ozone-induced foliar injury was positively correlated with cumulative ozone exposures, expressed as SUM40. Overall, the amount of foliar injury was better correlated to a flux-based approach rather than to an exposure-based approach. More severe foliar injuries were observed on plants growing at higher elevations. - Within heterogeneous environments, ozone flux does not completely explain the variation observed in ozone-induced visible injury

  13. Deciduous shrubs for ozone bioindication: Hibiscus syriacus as an example

    Energy Technology Data Exchange (ETDEWEB)

    Paoletti, Elena [Institut Plant Protection (IPP), National Council Research (CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Florence (Italy)], E-mail: e.paoletti@ipp.cnr.it; Ferrara, Anna Maria [Istituto per le Piante da Legno e l' Ambiente (IPLA), Corso Casale 476, 10132 Turin (Italy); Calatayud, Vicent; Cervero, Julia [Fundacion C.E.A.M., Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Giannetti, Fabio [Istituto per le Piante da Legno e l' Ambiente (IPLA), Corso Casale 476, 10132 Turin (Italy); Sanz, Maria Jose [Fundacion C.E.A.M., Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Manning, William J. [Department of Plant, Soil and Insect Sciences, University of Massachusetts, Amherst, MA 01003-9320 (United States)

    2009-03-15

    Ozone-like visible injury was detected on Hibiscus syriacus plants used as ornamental hedges. Weekly spray of the antiozonant ethylenediurea (EDU, 300 ppm) confirmed that the injury was induced by ambient ozone. EDU induced a 75% reduction in visible injury. Injury was more severe on the western than on the eastern exposure of the hedge. This factor of variability should be considered in ozone biomonitoring programmes. Seeds were collected and seedlings were artificially exposed to ozone in filtered vs. not-filtered (+30 ppb) Open-Top Chambers. The level of exposure inducing visible injury in the OTC seedlings was lower than that in the ambient-grown hedge. The occurrence of visible injury in the OTC confirmed that the ozone sensitivity was heritable and suggested that symptomatic plants of this deciduous shrub population can be successfully used as ozone bioindicators. EDU is recommended as a simple tool for diagnosing ambient ozone visible injury on field vegetation. - An Italian population of the deciduous shrub Hibiscus syriacus, a common ornamental species in temperate zones, is recommended as ozone bioindicator.

  14. Deciduous shrubs for ozone bioindication: Hibiscus syriacus as an example

    International Nuclear Information System (INIS)

    Paoletti, Elena; Ferrara, Anna Maria; Calatayud, Vicent; Cervero, Julia; Giannetti, Fabio; Sanz, Maria Jose; Manning, William J.

    2009-01-01

    Ozone-like visible injury was detected on Hibiscus syriacus plants used as ornamental hedges. Weekly spray of the antiozonant ethylenediurea (EDU, 300 ppm) confirmed that the injury was induced by ambient ozone. EDU induced a 75% reduction in visible injury. Injury was more severe on the western than on the eastern exposure of the hedge. This factor of variability should be considered in ozone biomonitoring programmes. Seeds were collected and seedlings were artificially exposed to ozone in filtered vs. not-filtered (+30 ppb) Open-Top Chambers. The level of exposure inducing visible injury in the OTC seedlings was lower than that in the ambient-grown hedge. The occurrence of visible injury in the OTC confirmed that the ozone sensitivity was heritable and suggested that symptomatic plants of this deciduous shrub population can be successfully used as ozone bioindicators. EDU is recommended as a simple tool for diagnosing ambient ozone visible injury on field vegetation. - An Italian population of the deciduous shrub Hibiscus syriacus, a common ornamental species in temperate zones, is recommended as ozone bioindicator

  15. Assimilated ozone from EOS-Aura: Evaluation of the tropopause region and tropospheric columns

    NARCIS (Netherlands)

    Stajner, I.; Wargan, K.; Pawson, S.; Hayashi, H.; Chang, L.-P.; Hudman, R.C.; Froidevaux, L.; Livesey, N.J.; Levelt, P.F.; Thompson, A.M.; Tarasick, D.W.; Stübi, R.; Andersen, S.B.; Yela, M.; König-Langlo, G.; Schmidlin, F.J.; Witte, J.C.

    2008-01-01

    Retrievals from the Microwave Limb Sounder (MLS) and the Ozone Monitoring Instrument (OMI) on EOS-Aura were included in the Goddard Earth Observing System version 4 (GEOS-4) ozone data assimilation system. The distribution and daily to seasonal evolution of ozone in the stratosphere and troposphere

  16. Pulmonary sensitivity to ozone exposure in sedentary versus chronically trained, female rats.

    Science.gov (United States)

    Gordon, Christopher J; Phillips, Pamela M; Beasley, Tracey E; Ledbetter, A; Aydin, Cenk; Snow, Samantha J; Kodavanti, Urmila P; Johnstone, Andrew F

    2016-06-01

    Epidemiological data suggest that a sedentary lifestyle may contribute to increased susceptibility for some environmental toxicants. We developed an animal model of active versus sedentary life style by providing female Sprague-Dawley rats with continuous access to running wheels. Sedentary rats were housed in standard cages without wheels. After training for 12 wks, rats were exposed to 0, 0.25, 0.5 or 1.0 ppm ozone [O3 for 5 h/d, 1 d/wk, for 6 wk (N = 10 per group)]. Body composition (%fat, lean and fluid) was monitored noninvasively over the course of the study. Ventilatory parameters [tidal volume, minute ventilation, frequency and enhanced pause (Penh)] were assessed using whole-body plethysmography prior to O3 and 24 h after the 5th O3 exposure. Trained rats lost ∼2% body fat after 12 wk of access to running wheels. Peak wheel activity was reduced by 40% after exposure to 1.0 ppm O3. After the 5th O3 exposure, body weight and %fat were reduced in sedentary but not trained rats. Penh was significantly elevated in sedentary but not trained rats the day after exposure to 1.0 ppm O3. However, lung lavage cell counts and biomarkers of pulmonary inflammation measured 1 day after the final exposure were inconsistently affected by training. Wheel running led to marked physiological responses along with some indication of improved pulmonary recovery from O3 exposure. However, wheel running with O3 exposure may also be a detriment for some pulmonary endpoints. Overall, a sedentary lifestyle may increase susceptibility to O3, but additional studies are needed.

  17. Acute effects of ozone on mortality from the "Air pollution and health : A European approach" project

    NARCIS (Netherlands)

    Gryparis, A; Forsberg, B; Katsouyanni, K; Analitis, A; Touloumi, G; Schwartz, J; Samoli, E; Medina, S; Anderson, HR; Niciu, EM; Wichmann, HE; Kriz, B; Kosnik, M; Skorkovsky, J; Vonk, JM; Dortbudak, Z

    2004-01-01

    In the Air Pollution and Health: A European Approach (APHEA2) project, the effects of ambient ozone concentrations on mortality were investigated. Data were collected on daily ozone concentrations, the daily number of deaths, confounders, and potential effect modifiers from 23 cities/areas for at

  18. From ozone depletion to biological UV damage

    Energy Technology Data Exchange (ETDEWEB)

    Tamm, E; Thomalla, E; Koepke, P [Munich Univ. (Germany). Meteorological Inst.

    1996-12-31

    Based on the ozone data from the Meteorological Observatory Hohenpeissenberg (MOHP: 47.8 deg N, 11.01 deg E) and corresponding mean atmospheric conditions, high resolution UV spectra are calculated with a complex radiation transfer model STAR. Biologically weighted UV spectra are investigated as integrated irradiances (dose rates) for maximum zenith angles and as daily integrals for selected days of the year. Ozone variation and uncertainty of action spectra are investigated

  19. From ozone depletion to biological UV damage

    Energy Technology Data Exchange (ETDEWEB)

    Tamm, E.; Thomalla, E.; Koepke, P. [Munich Univ. (Germany). Meteorological Inst.

    1995-12-31

    Based on the ozone data from the Meteorological Observatory Hohenpeissenberg (MOHP: 47.8 deg N, 11.01 deg E) and corresponding mean atmospheric conditions, high resolution UV spectra are calculated with a complex radiation transfer model STAR. Biologically weighted UV spectra are investigated as integrated irradiances (dose rates) for maximum zenith angles and as daily integrals for selected days of the year. Ozone variation and uncertainty of action spectra are investigated

  20. Changes in the carbon dioxide expirogram in response to ozone exposure

    International Nuclear Information System (INIS)

    Taylor, Adekemi B.; Lee, Genea M.; Nellore, Kavitha; Ben-Jebria, Abdellaziz; Ultman, James S.

    2006-01-01

    The objectives of this study were to quantify pulmonary responses to ozone (O 3 ) exposure by parameters computed from the carbon dioxide expirogram and to compare these responses to decrements in forced expired spirometry. Anatomical dead space (V D ) was determined from the pure dead space and transition regions of the expirogram. Four alternative parameters were computed from the alveolar plateau: slope (S), normalized slope (NS), peripheral cross-sectional area (A P ) and well-mixed peripheral volume (V MP ). Forty-seven healthy nonsmokers (25 men and 22 women) participated in two research sessions in which they exercised on a cycle ergometer for 1 h while orally inhaling either room air at a minute ventilation of 30.6 ± 3.6 L or room air mixed with 0.252 ± 0.029 ppm O 3 at a minute ventilation of 29.9 ± 3.7 L. Carbon dioxide expirograms were measured before exposure, 10 min after exposure and 70 min after exposure. Percent changes (mean ± SD) in expirogram parameters were significant (P ≤ 0.002) at both 10 and 70 min after O 3 exposure: V D (-4.2 ± 5.1, -3.3 ± 6.9), S(16.4 ± 17.9, +15.1 ± 20.2), NS(17.5 ± 15.4, +15.9 ± 19.2), A P (-8.1 ± 7.6, -7.7 ± 9.8) and V MP (-15.4 ± 13.0, -13.0 ± 15.2). Percent decrements of forced expired volume in one second (FEV 1 ) were also significant at both 10 min (-13.3 ± 13.4) and 70 min (-11.1 ± 9.2) following O 3 exposure. Changes in the expirogram as well as decrements in FEV 1 were not significant at either time point after air exposure. Thus, the CO 2 expirogram is useful for characterizing the effect of O 3 exposure on gas transport, and for supplementing forced expired spirometry that is frequently used to quantify lung mechanics

  1. Measurement of Ozone Production Sensor

    Directory of Open Access Journals (Sweden)

    M. Cazorla

    2010-05-01

    Full Text Available A new ambient air monitor, the Measurement of Ozone Production Sensor (MOPS, measures directly the rate of ozone production in the atmosphere. The sensor consists of two 11.3 L environmental chambers made of UV-transmitting Teflon film, a unit to convert NO2 to O3, and a modified ozone monitor. In the sample chamber, flowing ambient air is exposed to the sunlight so that ozone is produced just as it is in the atmosphere. In the second chamber, called the reference chamber, a UV-blocking film over the Teflon film prevents ozone formation but allows other processes to occur as they do in the sample chamber. The air flows that exit the two chambers are sampled by an ozone monitor operating in differential mode so that the difference between the two ozone signals, divided by the exposure time in the chambers, gives the ozone production rate. High-efficiency conversion of NO2 to O3 prior to detection in the ozone monitor accounts for differences in the NOx photostationary state that can occur in the two chambers. The MOPS measures the ozone production rate, but with the addition of NO to the sampled air flow, the MOPS can be used to study the sensitivity of ozone production to NO. Preliminary studies with the MOPS on the campus of the Pennsylvania State University show the potential of this new technique.

  2. Modification of the optoelectronic properties of two-dimensional MoS2 crystals by ultraviolet-ozone treatment

    Science.gov (United States)

    Yang, Hae In; Park, Seonyoung; Choi, Woong

    2018-06-01

    We report the modification of the optoelectronic properties of mechanically-exfoliated single layer MoS2 by ultraviolet-ozone exposure. Photoluminescence emission of pristine MoS2 monotonically decreased and eventually quenched as ultraviolet-ozone exposure time increased from 0 to 10 min. The reduction of photoluminescence emission accompanied reduction of Raman modes, suggesting structural degradation in ultraviolet-ozone exposed MoS2. Analysis with X-ray photoelectron spectroscopy revealed that the formation of Ssbnd O and Mosbnd O bonding increases with ultraviolet-ozone exposure time. Measurement of electrical transport properties of MoS2 in a bottom-gate thin-film transistor configuration suggested the presence of insulating MoO3 after ultraviolet-ozone exposure. These results demonstrate that ultraviolet-ozone exposure can significantly influence the optoelectronic properties of single layer MoS2, providing important implications on the application of MoS2 and other two-dimensional materials into optoelectronic devices.

  3. SUM06 Index for Damage to Flora from Ozone

    Data.gov (United States)

    U.S. Environmental Protection Agency — In addition to health effects in humans, Ozone exposure also causes damage to plants. One index used in calculating the potential damage to plants from Ozone...

  4. Ozone Atmospheric Pollution and Alzheimer's Disease: From Epidemiological Facts to Molecular Mechanisms.

    Science.gov (United States)

    Croze, Marine L; Zimmer, Luc

    2018-01-01

    Atmospheric pollution is a well-known environmental hazard, especially in developing countries where millions of people are exposed to airborne pollutant levels above safety standards. Accordingly, several epidemiological and animal studies confirmed its role in respiratory and cardiovascular pathologies and identified a strong link between ambient air pollution exposure and adverse health outcomes such as hospitalization and mortality. More recently, the potential deleterious effect of air pollution inhalation on the central nervous system was also investigated and mounting evidence supports a link between air pollution exposure and neurodegenerative pathologies, especially Alzheimer's disease (AD). The focus of this review is to highlight the possible link between ozone air pollution exposure and AD incidence. This review's approach will go from observational and epidemiological facts to the proposal of molecular mechanisms. First, epidemiological and postmortem human study data concerning residents of ozone-severely polluted megacities will be presented and discussed. Then, the more particular role of ozone air pollution in AD pathology will be described and evidenced by toxicological studies in rat or mouse with ozone pollution exposure only. The experimental paradigms used to reproduce in rodent the human exposure to ozone air pollution will be described. Finally, current insights into the molecular mechanisms through which ozone inhalation can affect the brain and play a role in AD development or progression will be recapitulated.

  5. Seasonal and diurnal gas exchange differences in ozone-sensitive common milkweed (Asclepias syriaca L.) in relation to ozone uptake.

    Science.gov (United States)

    Bergweiler, Chris; Manning, William J; Chevone, Boris I

    2008-03-01

    Stomatal conductance and net photosynthesis of common milkweed (Asclepias syriaca L.) plants in two different soil moisture regimes were directly quantified and subsequently modeled over an entire growing season. Direct measurements captured the dynamic response of stomatal conductance to changing environmental conditions throughout the day, as well as declining gas exchange and carbon assimilation throughout the growth period beyond an early summer maximum. This phenomenon was observed in plants grown both with and without supplemental soil moisture, the latter of which should theoretically mitigate against harmful physiological effects caused by exposure to ozone. Seasonally declining rates of stomatal conductance were found to be substantial and incorporated into models, making them less susceptible to the overestimations of effective exposure that are an inherent source of error in ozone exposure indices. The species-specific evidence presented here supports the integration of dynamic physiological processes into flux-based modeling approaches for the prediction of ozone injury in vegetation.

  6. Ozone induces glucose intolerance and systemic metabolic effects in young and aged brown Norway rats

    International Nuclear Information System (INIS)

    Bass, V.; Gordon, C.J.; Jarema, K.A.; MacPhail, R.C.; Cascio, W.E.; Phillips, P.M.; Ledbetter, A.D.; Schladweiler, M.C.; Andrews, D.; Miller, D.; Doerfler, D.L.; Kodavanti, U.P.

    2013-01-01

    Air pollutants have been associated with increased diabetes in humans. We hypothesized that ozone would impair glucose homeostasis by altering insulin signaling and/or endoplasmic reticular (ER) stress in young and aged rats. One, 4, 12, and 24 month old Brown Norway (BN) rats were exposed to air or ozone, 0.25 or 1.0 ppm, 6 h/day for 2 days (acute) or 2 d/week for 13 weeks (subchronic). Additionally, 4 month old rats were exposed to air or 1.0 ppm ozone, 6 h/day for 1 or 2 days (time-course). Glucose tolerance tests (GTT) were performed immediately after exposure. Serum and tissue biomarkers were analyzed 18 h after final ozone for acute and subchronic studies, and immediately after each day of exposure in the time-course study. Age-related glucose intolerance and increases in metabolic biomarkers were apparent at baseline. Acute ozone caused hyperglycemia and glucose intolerance in rats of all ages. Ozone-induced glucose intolerance was reduced in rats exposed for 13 weeks. Acute, but not subchronic ozone increased α 2 -macroglobulin, adiponectin and osteopontin. Time-course analysis indicated glucose intolerance at days 1 and 2 (2 > 1), and a recovery 18 h post ozone. Leptin increased day 1 and epinephrine at all times after ozone. Ozone tended to decrease phosphorylated insulin receptor substrate-1 in liver and adipose tissues. ER stress appeared to be the consequence of ozone induced acute metabolic impairment since transcriptional markers of ER stress increased only after 2 days of ozone. In conclusion, acute ozone exposure induces marked systemic metabolic impairments in BN rats of all ages, likely through sympathetic stimulation. - Highlights: • Air pollutants have been associated with increased diabetes in humans. • Acute ozone exposure produces profound metabolic alterations in rats. • Age influences metabolic risk factors in aging BN rats. • Acute metabolic effects are reversible and repeated exposure reduces these effects. • Ozone metabolic

  7. Ozone induces glucose intolerance and systemic metabolic effects in young and aged brown Norway rats

    Energy Technology Data Exchange (ETDEWEB)

    Bass, V. [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Gordon, C.J.; Jarema, K.A.; MacPhail, R.C. [Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Cascio, W.E. [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Phillips, P.M. [Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Ledbetter, A.D.; Schladweiler, M.C. [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Andrews, D. [Research Cores Unit, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Miller, D. [Curriculum in Toxicology, University of North Carolina, Chapel Hill, NC (United States); Doerfler, D.L. [Research Cores Unit, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Kodavanti, U.P., E-mail: kodavanti.urmila@epa.gov [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States)

    2013-12-15

    Air pollutants have been associated with increased diabetes in humans. We hypothesized that ozone would impair glucose homeostasis by altering insulin signaling and/or endoplasmic reticular (ER) stress in young and aged rats. One, 4, 12, and 24 month old Brown Norway (BN) rats were exposed to air or ozone, 0.25 or 1.0 ppm, 6 h/day for 2 days (acute) or 2 d/week for 13 weeks (subchronic). Additionally, 4 month old rats were exposed to air or 1.0 ppm ozone, 6 h/day for 1 or 2 days (time-course). Glucose tolerance tests (GTT) were performed immediately after exposure. Serum and tissue biomarkers were analyzed 18 h after final ozone for acute and subchronic studies, and immediately after each day of exposure in the time-course study. Age-related glucose intolerance and increases in metabolic biomarkers were apparent at baseline. Acute ozone caused hyperglycemia and glucose intolerance in rats of all ages. Ozone-induced glucose intolerance was reduced in rats exposed for 13 weeks. Acute, but not subchronic ozone increased α{sub 2}-macroglobulin, adiponectin and osteopontin. Time-course analysis indicated glucose intolerance at days 1 and 2 (2 > 1), and a recovery 18 h post ozone. Leptin increased day 1 and epinephrine at all times after ozone. Ozone tended to decrease phosphorylated insulin receptor substrate-1 in liver and adipose tissues. ER stress appeared to be the consequence of ozone induced acute metabolic impairment since transcriptional markers of ER stress increased only after 2 days of ozone. In conclusion, acute ozone exposure induces marked systemic metabolic impairments in BN rats of all ages, likely through sympathetic stimulation. - Highlights: • Air pollutants have been associated with increased diabetes in humans. • Acute ozone exposure produces profound metabolic alterations in rats. • Age influences metabolic risk factors in aging BN rats. • Acute metabolic effects are reversible and repeated exposure reduces these effects. • Ozone

  8. Evaluation of The Surface Ozone Concentrations In Greater Cairo Area With Emphasis On Helwan, Egypt

    International Nuclear Information System (INIS)

    Ramadan, A.; Kandil, A.T.; Abd Elmaged, S.M.; Mubarak, I.

    2011-01-01

    Various biogenic and anthropogenic sources emit huge quantities of surface ozone. The main purpose of this study is to evaluate the surface ozone levels present at Helwan area in order to improve the knowledge and understanding troposphere processes. Surface Ozone has been measured at 2 sites at Helwan; these sites cover the most populated area in Helwan. Ozone concentration is continuously monitored by UV absorption photometry using the equipment O 3 41 M UV Photometric Ozone Analyzer. The daily maximum values of the ozone concentration in the greater Cairo area have approached but did not exceeded the critical levels during the year 2008. Higher ozone concentrations at Helwan are mainly due to the transport of ozone from regions further to the north of greater Cairo and to a lesser extent of ozone locally generated by photochemical smog process. The summer season has the largest diurnal variation, with the tendency of the daily ozone maxima occur in the late afternoon. The night time concentration of ozone was significantly higher at Helwan because there are no fast acting sinks, destroying ozone since the average night time concentration of ozone is maintained at 40 ppb at the site. No correlation between the diurnal total suspended particulate (TSP) matter and the diurnal cumulative ozone concentration was observed during the Khamasin period

  9. Exposure to environmentally-relevant levels of ozone negatively influence pollen and fruit development.

    Science.gov (United States)

    Gillespie, Colin; Stabler, Daniel; Tallentire, Eva; Goumenaki, Eleni; Barnes, Jeremy

    2015-11-01

    A combination of in vitro and in vivo studies on tomato (Lycopersicon esculentum Mill. cv. Triton) revealed that environmentally-relevant levels of ozone (O3) pollution adversely affected pollen germination, germ tube growth and pollen-stigma interactions - pollen originating from plants raised in charcoal-Purafil(®) filtered air (CFA) exhibited reduced germ tube development on the stigma of plants exposed to environmentally-relevant levels of O3. The O3-induced decline in in vivo pollen viability was reflected in increased numbers of non-fertilized and fertilized non-viable ovules in immature fruit. Negative effects of O3 on fertilization occurred regardless of the timing of exposure, with reductions in ovule viability evident in O3 × CFA and CFA × O3 crossed plants. This suggests O3-induced reductions in fertilization were associated with reduced pollen viability and/or ovule development. Fruit born on trusses independently exposed to 100 nmol mol(-1) O3 (10 h d(-1)) from flowering exhibited a decline in seed number and this was reflected in a marked decline in the weight and size of individual fruit - a clear demonstration of the direct consequence of the effects of the pollutant on reproductive processes. Ozone exposure also resulted in shifts in the starch and ascorbic acid (Vitamin C) content of fruit that were consistent with accelerated ripening. The findings of this study draw attention to the need for greater consideration of, and possibly the adoption of weightings for the direct impacts of O3, and potentially other gaseous pollutants, on reproductive biology during 'risk assessment' exercises. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Trends of Ozone in Switzerland since 1992 (TROZOS)

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez, C.; Mathis, H.; Furger, M.; Prevot, A.S.H

    2004-07-01

    This work reports on the trends of the daily afternoon (noon to midnight) maximum ozone concentrations at 15 of the 16 stations of the Swiss air quality monitoring network (NABEL) during the period 1992-2002. The use of numerous meteorological parameters and additional data allowed a detailed seasonal analysis of the influence of the weather on the ozone maxima at the different stations. An analysis of covariance (ANCOVA) was performed separately for each station and season in order to detect the parameters which best explain the variability of the daily ozone maximum concentrations. During the warm seasons (summer and spring) the most explanatory parameters are those related to the ozone production, in particular the afternoon temperature. In winter, the most explanatory variables are the ones influencing the vertical mixing and thus the ozone destruction by titration with NO and dry deposition, like the afternoon global radiation. The trends of both the measured and meteorologically corrected ozone maxima were calculated. The year-to-year variability in the ozone maxima was lowered by a factor of 3 by the meteorological correction. Significantly positive trends of corrected ozone maxima of 0.3 - 1.1 ppb/year were found at the low altitude stations in winter and autumn as well as at Lausanne - urban station - in all the seasons, mainly due to the lower loss of ozone by reaction with NO as a consequence of the decreased emissions of primary pollutants during the 90s. This could be partially confirmed by the lower trends of O{sub X} (sum O{sub 3} of and NO{sub 2}) maxima compared to the trends in ozone maxima. The absence of negative trends of the median or mean ozone maxima north of the Alps in summer suggests that the decrease in the emissions of ozone precursors did not have a strong impact on the afternoon maximum ozone concentrations during the last decade. In contrast to the project TOSS (Trends of Ozone in Southern Switzerland), no significantly negative

  11. Trends of Ozone in Switzerland since 1992 (TROZOS)

    International Nuclear Information System (INIS)

    Ordonez, C.; Mathis, H.; Furger, M.; Prevot, A.S.H.

    2004-07-01

    This work reports on the trends of the daily afternoon (noon to midnight) maximum ozone concentrations at 15 of the 16 stations of the Swiss air quality monitoring network (NABEL) during the period 1992-2002. The use of numerous meteorological parameters and additional data allowed a detailed seasonal analysis of the influence of the weather on the ozone maxima at the different stations. An analysis of covariance (ANCOVA) was performed separately for each station and season in order to detect the parameters which best explain the variability of the daily ozone maximum concentrations. During the warm seasons (summer and spring) the most explanatory parameters are those related to the ozone production, in particular the afternoon temperature. In winter, the most explanatory variables are the ones influencing the vertical mixing and thus the ozone destruction by titration with NO and dry deposition, like the afternoon global radiation. The trends of both the measured and meteorologically corrected ozone maxima were calculated. The year-to-year variability in the ozone maxima was lowered by a factor of 3 by the meteorological correction. Significantly positive trends of corrected ozone maxima of 0.3 - 1.1 ppb/year were found at the low altitude stations in winter and autumn as well as at Lausanne - urban station - in all the seasons, mainly due to the lower loss of ozone by reaction with NO as a consequence of the decreased emissions of primary pollutants during the 90s. This could be partially confirmed by the lower trends of O X (sum O 3 of and NO 2 ) maxima compared to the trends in ozone maxima. The absence of negative trends of the median or mean ozone maxima north of the Alps in summer suggests that the decrease in the emissions of ozone precursors did not have a strong impact on the afternoon maximum ozone concentrations during the last decade. In contrast to the project TOSS (Trends of Ozone in Southern Switzerland), no significantly negative trends of ozone

  12. Ozone air pollution effects on tree-ring growth,{delta}{sup 13}C, visible foliar injury and leaf gas exchange in three ozone-sensitive woody plant species

    Energy Technology Data Exchange (ETDEWEB)

    Novak, K. [Swiss Federal Inst. for Forest, Snow and Landscape Research, Birmensdorf (Switzerland); Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Zurich (Switzerland); Saurer, M. [Paul Scherrer Inst. Villigen (Switzerland); Fuhrer, J. [Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Zurich (Switzerland); Skelly, J.M. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Plant Pathology; Krauchi, N.; Schaub, M. [Swiss Federal Inst. for Forest, Snow and Landscape Research, Birmensdorf (Switzerland)

    2007-07-15

    Species specific plant responses to tropospheric ozone pollution depend on a range of morphological, biochemical and physiological characteristics as well as environmental factors. The effects of ambient tropospheric ozone on annual tree-ring growth, {delta}{sup 13} C in the rings, leaf gas exchange and ozone-induced visible foliar injury in three ozone-sensitive woody plant species in southern Switzerland were assessed during the 2001 and 2002 growing seasons. Seedlings of Populus nigra L., Viburnum lantana L. and Fraxinus excelsior L. were exposed to charcoal-filtered air and non-filtered air in open-top chambers, and to ambient air (AA) in open plots. The objective was to determine if a relationship exists between measurable ozone-induced effects at the leaf level and subsequent changes in annual tree-ring growth and {delta} {sup 13} C signatures. The visible foliar injury, early leaf senescence and premature leaf loss in all species was attributed to the ambient ozone exposures in the region. Ozone had pronounced negative effects on net photosynthesis and stomatal conductance in all species in 2002 and in V. lantana and F. excelsior in 2001. Water-use efficiency decreased and intercellular carbon dioxide concentrations increased in all species in response to ozone in 2002 only. The width and {delta}{sup 13} C of the 2001 and 2002 growth rings were measured for all species at the end of the 2002 growing season. Significant ozone-induced effects at the leaf level did not correspond to reduced tree-ring growth or increased {delta}{sup 13} C in all species, suggesting that the timing of ozone exposure and extent of leaf-level responses may be relevant in determining the sensitivity of tree productivity to ozone exposure. 48 refs., 4 tabs., 2 figs.

  13. Spatial clustering and meteorological drivers of summer ozone in Europe

    Science.gov (United States)

    Carro-Calvo, Leopoldo; Ordóñez, Carlos; García-Herrera, Ricardo; Schnell, Jordan L.

    2017-10-01

    We have applied the k-means clustering technique on a maximum daily 8-h running average near-surface ozone (MDA8 O3) gridded dataset over Europe at 1° × 1° resolution for summer 1998-2012. This has resulted in a spatial division of nine regions where ozone presents coherent spatiotemporal patterns. The role of meteorology in the variability of ozone at different time scales has been investigated by using daily meteorological fields from the NCEP-NCAR meteorological reanalysis. In the five regions of central-southern Europe ozone extremes (exceedances of the summer 95th percentile) occur mostly under anticyclonic circulation or weak sea level pressure gradients which trigger elevated temperatures and the recirculation of air masses. In the four northern regions extremes are associated with high-latitude anticyclones that divert the typical westerly flow at those latitudes and cause the advection of aged air masses from the south. The impact of meteorology on the day-to-day variability of ozone has been assessed by means of two different types of multiple linear models. These include as predictors meteorological fields averaged within the regions (;region-based; approach) or synoptic indices indicating the degree of resemblance between the daily meteorological fields over a large domain (25°-70° N, 35° W - 35° E) and their corresponding composites for extreme ozone days (;index-based; approach). With the first approach, a reduced set of variables, always including daily maximum temperature within the region, explains 47-66% of the variability (adjusted R2) in central-southern Europe, while more complex models are needed to explain 27-49% of the variability in the northern regions. The index-based approach yields better results for the regions of northern Europe, with adjusted R2 = 40-57%. Finally, both methodologies have also been applied to reproduce the interannual variability of ozone, with the best models explaining 66-88% of the variance in central

  14. Ozone and nitrogen oxides in surface air in Russia: TROICA experiments.

    Science.gov (United States)

    Pankratova, N.; Elansky, N.; Belikov, I.; Shumskiy, R.

    2009-04-01

    The results of measurements of surface ozone and nitrogen oxides concentrations over the continental regions of Russia are discussed. The measurements were done during 10 TROICA experiments (Transcontinental Observations Into the Chemistry of the Atmosphere). The TROICA experiment started in 1995. By the present moment ten expeditions along the Trans-Siberian railroad from Moscow to Vladivostok (around 9300 km) are carried out. We separate data sets into unpolluted and polluted areas to study temporal and spatial features. Moreover we analyzed cities (more then 100 cities). About 50% of all data corresponds to unpolluted conditions. The data collected are used in an analysis of the physical and chemical processes occurring over continental Russia. In this work the estimations of seasonal and daily ozone and NOx distribution were made. The seasonal distribution of ozone for TROICA experiments concentration considerably differs from ozone distribution at Mace Head (Ireland) and Hohenpeissenberg (Germany) stations and well agrees with the ozone distribution at Zotino (Russia, East Siberia). The same concerns also a daily variability. The ozone concentration gradient is presented. Ozone concentration gradually increases in the eastward direction. Its result of the air transport from polluted regions of Europe and ozone depletions, oxidations of CH4 in Siberia, forest fires in Siberia and around Baikal Lake, regional transport of burning products from Northern China. Significant factor of ozone increasing is stratospheric-tropospheric exchange. It appears in TROICA-3 experiment. During several hours ozone concentration was more then 60 ppbv. The areas of photochemical ozone generation in polluted air are also detected. We estimate anthropogenic and natural factors, which are responsible for sharp ozone concentration increasing. Acknowledgments. The work was supported by International Science and Technology Center (ISTC) under contract No. 2770 and by Russian Basic

  15. Foliar nutrient status of Pinus ponderosa exposed to ozone and acid rain

    International Nuclear Information System (INIS)

    Anderson, P.D.; Houpis, J.L.J.

    1991-01-01

    A direct effect of foliar exposure to acid rain may be increased leaching of nutrient elements. Ozone exposure, through degradation of the cuticle and cellular membranes, may also result in increased nutrient leaching. To test these hypotheses, the foliar concentrations of 13 nutrient elements were monitored for mature branches of three clones of Pinus ponderosa exposed to ozone and/or acid rain. The three clones represented three distinct levels of phenotypic vigor. Branches were exposed to charcoal filtered, ambient, or 2 x ambient concentrations of ozone and received no acid rain (NAP), pH 5.1 rain (5.1), or pH 3.0 (3.0) rain. Following 10 months of continuous ozone exposure and 3 months of weekly rain applications, the concentrations of P and Mg differed significantly among rain treatments with a ranking of: 5.1 < NAP < 3.0. The S concentration increased with rain application regardless of pH. For the clones of moderate and low vigor, the concentration of N decreased with increasing rain acidity. There was no evidence of significant ozone or ozone x acid rain response. Among the three families, high phenotypic vigor was associated with significantly greater concentrations of N, P, K, Mg, B and An. These results indicate generally negligible leaching as a result of exposure to acid rain and/or ozone for one growing season. Increases in foliar concentrations of S, Mg and P are possibly the result of evaporative surface deposition from the rain solution

  16. Ozone-Induced Pulmonary Injury and Inflammation are Modulated by Adrenal-Derived Stress Hormones

    Science.gov (United States)

    Ozone exposure promotes pulmonary injury and inflammation. Previously we have characterized systemic changes that occur immediately after acute ozone exposure and are mediated by neuro-hormonal stress response pathway. Both HPA axis and sympathetic tone alterations induce the rel...

  17. Thermoluminescence as a tool for monitoring ozone-stressed plants

    Energy Technology Data Exchange (ETDEWEB)

    Skotnica, J.; Gilbert, M.; Weingart, I.; Wilhelm, C

    2003-05-01

    Thermoluminescence parameters are more sensitive to ozone than fluorescence parameters (F{sub 0}, F{sub M}, F{sub v}/F{sub M}). - The effect of ozone (6 h, various concentrations from 0 to 350 ppb) on barley (Hordeum vulgare L., cv. Bomi) and tomato (Lycopersicon esculentum L., cv. Yellow Cherry) leaves was investigated in parallel by thermoluminescence (TL) and fluorescence (FL) methods. Several significant changes were found in TL glow curves measured after excitation by one single turnover flash at +2 deg. C in the temperature range from 2 to 170 deg. C immediately after ozone exposure. Contrary to TL, ozone induced only negligible changes in FL parameters F{sub 0}, F{sub M} and F{sub v}/F{sub M}. Measurements done 24 h after ozone exposure showed partial recovery of ozone-induced changes. The extent of recovery was not the same in different parts of TL curves. Fluorescence parameters were not significantly changed. The results demonstrate that TL parameters are more sensitive to ozone than conventially used FL parameters F{sub 0}, F{sub M} and F{sub v}/F{sub M}. Moreover, TL measurements seem to give information not only about the PSII electron transport, but also about the extent of oxidative damage and membrane lipid peroxidation. It is concluded, that TL can be a highly informative tool for monitoring the impact of ozone on plants.

  18. Trends in Surface Level Ozone Observations from Human-health Relevant Metrics: Results from the Tropospheric Ozone Assessment Report (TOAR)

    Science.gov (United States)

    Fleming, Z. L.; von Schneidemesser, E.; Doherty, R. M.; Malley, C.; Cooper, O. R.; Pinto, J. P.; Colette, A.; Xu, X.; Simpson, D.; Schultz, M.; Hamad, S.; Moola, R.; Solberg, S.; Feng, Z.

    2017-12-01

    Ozone is an air pollutant formed in the atmosphere from precursor species (NOx, VOCs, CH4, CO) that is detrimental to human health and ecosystems. The global Tropospheric Ozone Assessment Report (TOAR) initiative has assembled a global database of surface ozone observations and generated ozone exposure metrics at thousands of measurement sites around the world. This talk will present results from the assessment focused on those indicators most relevant to human health. Specifically, the trends in ozone, comparing different time periods and patterns across regions and among metrics will be addressed. In addition, the fraction of population exposed to high ozone levels and how this has changed between 2000 and 2014 will also be discussed. The core time period analyzed for trends was 2000-2014, selected to include a greater number of sites in East Asia. Negative trends were most commonly observed at many US and some European sites, whereas many sites in East Asia showed positive trends, while sites in Japan showed more of a mix of positive and negative trends. More than half of the sites showed a common direction and significance in the trends for all five human-health relevant metrics. The peak ozone metrics indicate a reduction in exposure to peak levels of ozone related to photochemical episodes in Europe and the US. A considerable number of European countries and states within the US have shown a decrease in population-weighted ozone over time. The 2000-2014 results will be augmented and compared to the trend analysis for additional time periods that cover a greater number of years, but by necessity are based on fewer sites. Trends are found to be statistically significant at a larger fraction of sites with longer time series, compared to the shorter (2000-2014) time series.

  19. Ozone and infection of geranium flowers by Botrytis cinerea

    Energy Technology Data Exchange (ETDEWEB)

    Manning, W.J.; Feder, W.A.; Perkins, I.

    1970-01-01

    Flowering plants of geranium cultivars were exposed to 0.2, 0.35, and 0.55 ppm ozone for 4-hr periods at 20/sup 0/C in a greenhouse fumigation chamber. Three fully-opened flower heads were sprayed with a spore suspension of Botrytis cinerea at 2000, 1000, or 500 spores/ml immediately before exposure to ozone began. Sterile distilled water was sprayed on noninoculated flower heads. All flowers were examined for evidence of infection 24 hr after the end of the ozone-exposure periods. All flower heads were then removed and placed in wet, loosely tied plastic bags and incubated at 20/sup 0/C for 72 hr, with examination at 24-hr intervals for evidence of infection. Ozone at 0.2 ppm did not injure the plants or prevent or inhibit flower infection by B. cinerea at all inoculum levels. Natural infection also occurred on some noninoculated flowers. Ozone at 0.35 ppm did not injure the plants or prevent infection, but did inhibit pathogenesis at the 500-spore/ml inoculum level and on noninoculated flowers. Ozone at 0.55 ppm caused moderate injury on all plants. Ozone at this level did not prevent infection, but did restrict pathogenesis on all inoculated and noninoculated flowers.

  20. Photochemical model evaluation of the ground-level ozone impacts on ambient air quality and vegetation health in the Alberta oil sands region: Using present and future emission scenarios

    Science.gov (United States)

    Vijayaraghavan, Krish; Cho, Sunny; Morris, Ralph; Spink, David; Jung, Jaegun; Pauls, Ron; Duffett, Katherine

    2016-09-01

    One of the potential environmental issues associated with oil sands development is increased ozone formation resulting from NOX and volatile organic compound emissions from bitumen extraction, processing and upgrading. To manage this issue in the Athabasca Oil Sands Region (AOSR) in northeast Alberta, a regional multi-stakeholder group, the Cumulative Environmental Management Association (CEMA), developed an Ozone Management Framework that includes a modelling based assessment component. In this paper, we describe how the Community Multi-scale Air Quality (CMAQ) model was applied to assess potential ground-level ozone formation and impacts on ambient air quality and vegetation health for three different ozone precursor cases in the AOSR. Statistical analysis methods were applied, and the CMAQ performance results met the U.S. EPA model performance goal at all sites. The modelled 4th highest daily maximum 8-h average ozone concentrations in the base and two future year scenarios did not exceed the Canada-wide standard of 65 ppb or the newer Canadian Ambient Air Quality Standards of 63 ppb in 2015 and 62 ppb in 2020. Modelled maximum 1-h ozone concentrations in the study were well below the Alberta Ambient Air Quality Objective of 82 ppb in all three cases. Several ozone vegetation exposure metrics were also evaluated to investigate the potential impact of ground-level ozone on vegetation. The chronic 3-months SUM60 exposure metric is within the CEMA baseline range (0-2000 ppb-hr) everywhere in the AOSR. The AOT40 ozone exposure metric predicted by CMAQ did not exceed the United Nations Economic Commission for Europe (UN/ECE) threshold of concern of 3000 ppb-hr in any of the cases but is just below the threshold in high-end future emissions scenario. In all three emission scenarios, the CMAQ predicted W126 ozone exposure metric is within the CEMA baseline threshold of 4000 ppb-hr. This study outlines the use of photochemical modelling of the impact of an industry (oil

  1. Effects of long-term ambient ozone exposure on biomass and wood traits in poplar treated with ethylenediurea (EDU)

    International Nuclear Information System (INIS)

    Carriero, G.; Emiliani, G.; Giovannelli, A.; Hoshika, Y.; Manning, W.J.; Traversi, M.L.; Paoletti, E.

    2015-01-01

    This is the longest continuous experiment where ethylenediurea (EDU) was used to protect plants from ozone (O 3 ). Effects of long-term ambient O 3 exposure (23 ppm h AOT40) on biomass of an O 3 sensitive poplar clone (Oxford) were examined after six years from in-ground planting. Trees were irrigated with either water or 450 ppm EDU. Above (−51%) and below-ground biomass (−47%) was reduced by O 3 although the effect was significant only for stem and coarse roots. Ambient O 3 decreased diameter of the lower stem, and increased moisture content along the stem of not-protected plants (+16%). No other change in the physical wood structure was observed. A comparison with a previous assessment in the same experiment suggested that O 3 effects on biomass partitioning to above-ground organs depend on the tree ontogenetic stage. The root/shoot ratios did not change, suggesting that previous short-term observations of reduced allocation to tree roots may be overestimated. - Highlights: • 6-y ambient O 3 exposure was investigated in a sensitive poplar clone. • EDU irrigation protected poplar against ambient O 3 exposure. • O 3 reduced biomass of roots and stem, but did not change biomass allocation. • O 3 decreased stem diameter only in the lower third of the stem. • O 3 increased moisture content of the wood along the stem. - Ozone exposure reduced lateral branching, leaves and roots in younger trees, and affected stem and roots in older trees, while shoot/root ratios did not change.

  2. Influence of ozone on RNA and protein content of Lemna minor L

    Energy Technology Data Exchange (ETDEWEB)

    Craker, L E

    1972-01-01

    The amount of RNA and protein in Lemna minor L. plants decreased after exposure to ozone, as compared with control plants receiving no ozone treatment. Differences in RNA and protein content between control and ozone-treated Lemna plants were detectable immediately following ozone treatments and remained throughout the 24 h sampling time.

  3. Regional differences in DNA replication in nasal epithelium following acute ozone or cigarette smoke exposure

    International Nuclear Information System (INIS)

    Johnson, N.F.; Hotchkiss, J.A.; Harkema, J.R.; Henderson, R.F.; Mauderly, J.L.; Cuddihy, R.G.

    1988-01-01

    The epithelium of the anterior nasal cavity is composed of four cell types, squamous, respiratory, cuboidal, and olfactory cells. We monitored proliferation In these tissues by bromodeoxy-uridine (BrdUrd) incorporation; the labeled cells were identified by using a monoclonal antibody that recognizes BrdUrd. The respiratory, cuboidal and olfactory epithelia had low cell turnover (1-labeled ceIl/mm basal lamina). Squamous epithelium contained 40-labeled cells per mm basal lamina. Following exposure to diluted mainstream cigarette smoke, a transient, but marked increase in DNA replication was seen in the cuboidal epithelium. In contrast, ozone exposure was associated with DNA replication in the olfactory and respiratory epithelium, as well as in the cuboidal epithelium. These studies show that the sensitivity of nasal epithelium to irritants can be assayed by measuring DNA replication. (author)

  4. Regional differences in DNA replication in nasal epithelium following acute ozone or cigarette smoke exposure

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, N F; Hotchkiss, J A; Harkema, J R; Henderson, R F; Mauderly, J L; Cuddihy, R G

    1988-12-01

    The epithelium of the anterior nasal cavity is composed of four cell types, squamous, respiratory, cuboidal, and olfactory cells. We monitored proliferation In these tissues by bromodeoxy-uridine (BrdUrd) incorporation; the labeled cells were identified by using a monoclonal antibody that recognizes BrdUrd. The respiratory, cuboidal and olfactory epithelia had low cell turnover (1-labeled ceIl/mm basal lamina). Squamous epithelium contained 40-labeled cells per mm basal lamina. Following exposure to diluted mainstream cigarette smoke, a transient, but marked increase in DNA replication was seen in the cuboidal epithelium. In contrast, ozone exposure was associated with DNA replication in the olfactory and respiratory epithelium, as well as in the cuboidal epithelium. These studies show that the sensitivity of nasal epithelium to irritants can be assayed by measuring DNA replication. (author)

  5. Daily stressors, trauma exposure, and mental health among stateless Rohingya refugees in Bangladesh.

    Science.gov (United States)

    Riley, Andrew; Varner, Andrea; Ventevogel, Peter; Taimur Hasan, M M; Welton-Mitchell, Courtney

    2017-06-01

    The Rohingya of Myanmar are a severely persecuted minority who form one of the largest groups of stateless people; thousands of them reside in refugee camps in southeastern Bangladesh. There has been little research into the mental health consequences of persecution, war, and other historical trauma endured by the Rohingya; nor has the role of daily environmental stressors associated with continued displacement, statelessness, and life in the refugee camps, been thoroughly researched. This cross-sectional study examined: trauma history, daily environmental stressors, and mental health outcomes for 148 Rohingya adults residing in Kutupalong and Nayapara refugee camps in Bangladesh. Results indicated high levels of mental health concerns: posttraumatic stress disorder (PTSD), depression, somatic complaints, and associated functional impairment. Participants also endorsed local idioms of distress, including somatic complaints and concerns associated with spirit possession. The study also found very high levels of daily environmental stressors associated with life in the camps, including problems with food, lack of freedom of movement, and concerns regarding safety. Regression and associated mediation analyses indicated that, while there was a direct effect of trauma exposure on mental health outcomes (PTSD symptoms), daily environmental stressors partially mediated this relationship. Depression symptoms were associated with daily stressors, but not prior trauma exposure. These findings indicate that daily stressors play a pivotal role in mental health outcomes of populations affected by collective violence and statelessness. It is, therefore, important to consider the role and effects of environmental stressors associated with life in refugee camps on the mental health and psychosocial well-being of stateless populations such as the Rohingya, living in protracted humanitarian environments.

  6. Daily exposure to either a high- or low-energy-dense snack food reduces its reinforcing value in adolescents.

    Science.gov (United States)

    Temple, Jennifer L; Van der Kloet, Erika; Atkins, Amanda M; Crandall, Amanda K; Ziegler, Amanda M

    2017-02-01

    To examine the impact of daily exposure to a low-energy-dense (LED) or a high-energy-dense (HED) snack food on its reinforcing value (RRV) in adolescents with healthy weight, overweight, or obesity. A parallel-group, randomized trial was used to assess RRV of LED or HED snack food at baseline and again after exposure to that snack food daily for 2 weeks in 77 adolescents, aged 13 to 17 years. Information on eating-related subject characteristics was also collected at baseline. After 2 weeks of daily exposure, the RRV of the snack foods was significantly reduced in all participants, regardless of energy density or participant weight status. Among individuals who were high in dietary restraint only, those randomized to LED food found their snack food less reinforcing at baseline than those who were randomized to HED food. Baseline eating-related variables also differed as a function of weight status. Daily exposure to snack food in adolescents reduces the RRV of that food regardless of snack food energy density or weight status of the adolescent. This finding differs from adults, suggesting that increases in RRV of HED food after repeated exposure may develop after adolescence. © 2017 The Obesity Society.

  7. Extreme value modeling for the analysis and prediction of time series of extreme tropospheric ozone levels: a case study.

    Science.gov (United States)

    Escarela, Gabriel

    2012-06-01

    The occurrence of high concentrations of tropospheric ozone is considered as one of the most important issues of air management programs. The prediction of dangerous ozone levels for the public health and the environment, along with the assessment of air quality control programs aimed at reducing their severity, is of considerable interest to the scientific community and to policy makers. The chemical mechanisms of tropospheric ozone formation are complex, and highly variable meteorological conditions contribute additionally to difficulties in accurate study and prediction of high levels of ozone. Statistical methods offer an effective approach to understand the problem and eventually improve the ability to predict maximum levels of ozone. In this paper an extreme value model is developed to study data sets that consist of periodically collected maxima of tropospheric ozone concentrations and meteorological variables. The methods are applied to daily tropospheric ozone maxima in Guadalajara City, Mexico, for the period January 1997 to December 2006. The model adjusts the daily rate of change in ozone for concurrent impacts of seasonality and present and past meteorological conditions, which include surface temperature, wind speed, wind direction, relative humidity, and ozone. The results indicate that trend, annual effects, and key meteorological variables along with some interactions explain the variation in daily ozone maxima. Prediction performance assessments yield reasonably good results.

  8. Spatial associations between social groups and ozone air pollution exposure in the Beijing urban area.

    Science.gov (United States)

    Zhao, Xinyi; Cheng, Hongguang; He, Siyuan; Cui, Xiangfen; Pu, Xiao; Lu, Lu

    2018-07-01

    Few studies have linked social factors to air pollution exposure in China. Unlike the race or minority concepts in western countries, the Hukou system (residential registration system) is a fundamental reason for the existence of social deprivation in China. To assess the differences in ozone (O 3 ) exposure among social groups, especially groups divided by Hukou status, we assigned estimates of O 3 exposure to the latest census data of the Beijing urban area using a kriging interpolation model. We developed simultaneous autoregressive (SAR) models that account for spatial autocorrelation to identify the associations between O 3 exposure and social factors. Principal component regression was used to control the multicollinearity bias as well as explore the spatial structure of the social data. The census tracts (CTs) with higher proportions of persons living alone and migrants with non-local Hukou were characterized by greater exposure to ambient O 3 . The areas with greater proportions of seniors had lower O 3 exposure. The spatial distribution patterns were similar among variables including migrants, agricultural population and household separation (population status with separation between Hukou and actual residences), which fit the demographic characteristics of the majority of migrants. Migrants bore a double burden of social deprivation and O 3 pollution exposure due to city development planning and the Hukou system. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. Carryover effects of acid rain and ozone on the physiology of multiple flushes of loblolly pine seedlings

    International Nuclear Information System (INIS)

    Sasek, T.W.; Richardson, C.J.; Fendick, E.A.; Bevington, S.R.; Kress, L.W.

    1991-01-01

    The effects of acid rain and ozone exposure on loblolly pine (Pinus taeda L.) seedlings in the Piedmont of North Carolina were assessed over two exposure seasons (1987-1988). Direct effects and carryover effects of long-term exposure on the photosynthetic potential and photopigment concentrations of different needle age-classes were studied. Three half-sib families were grown in open-top field chambers and exposed two acid rain treatments and five ozone exposures delivered in proportion to ambient concentrations in a complete factorial design. Ozone significantly affected photosynthesis but there were no statistically significant effects of acid rain nor any ozone x acid rain interactions. In 1987, photosynthesis of the 1987 first-flush progressively diverged among the ozone treatments except between charcoal-filtered and nonfiltered air (NF). At the end of the first season, photosynthesis was reduced 24% at 1.5x compared to CF and more than 80% at 2.25x and 3.0x. Chlorophyll and carotenoid concentrations were similarly reduced at elevated ozone exposures. In 1988, photosynthesis of the 1987 first-flush in the elevated ozone treatments remained lower. Early in the second season, the 1988 first-flush had a 25% to 50% lower photosynthetic potential at 2.25x and 3.0x compared to CF. This carryover effect on the photosynthetic potential before significant cumulative exposure was progressively smaller in the later 1988 flushes. In the late season flushes in the highest ozone treatments, photosynthesis was significantly higher than in the lower ozone treatments

  10. Enhanced response to ozone exposure during the follicular phase of the menstrual cycle

    Energy Technology Data Exchange (ETDEWEB)

    Fox, S.D.; Adams, W.C.; Brookes, K.A.; Lasley, B.L. (Univ. of Calfornia, Davis (United States))

    1993-08-01

    Exposure to ozone (O[sub 3]), a toxic component of photochemical smog, results in significant airway inflammation, respiratory discomfort, and pulmonary function impairment. These effects can be reduced via pretreatment with anti-inflammatory agents. Progesterone, a gonadal steroid, is known to reduce general inflammation in the uterine endometrium. However, it is not known whether fluctuation in blood levels of progesterone, which are experienced during the normal female menstrual cycle, could alter O[sub 3] inflammatory-induced pulmonary responses. In this study, we tested the hypothesis that young, adult females are more responsive to O[sub 3] inhalation with respect to pulmonary function impairment during their follicular (F) menstrual phase when progesterone levels are lowest that during their mid-luteal (ML) phase when progesterone levels are highest. Nine subjects with normal ovarian function were exposed in random order for 1 hour each to filtered air and to 0.30 ppm O[sub 3] in their F and ML menstrual phases. Ozone responsiveness was measured by percent change in pulmonary function from pre- to postexposure. Significant gas concentration effects (filtered air versus O[sub 3]) were observed for forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV[sub 1]), and forced expiratory flow between 25 and 75% of FVC (FEF[sub 25-75]), showed a significant menstrual phase and gas concentration interaction effect, with larger decrements observed in the F menstrual phase when progesterone concentrations were significantly lower. We conclude that young, adult females appear to be more responsive to acute O[sub 3] exposure during the F phase than during the ML phase of their menstrual cycles. This difference in pulmonary function response could be related to the anti-inflammatory effects of increased progesterone concentrations during the luteal phase.

  11. NCEP TOVS & SBUV/2 Column Ozone GRIB Format Daily L3 Global 1 Deg Lat/Lon

    Data.gov (United States)

    National Aeronautics and Space Administration — TOAST is a new near real-time operational ozone map generated by combining TOVS tropospheric and lower stratospheric (4 to 23 km) ozone retrievals with SBUV/2...

  12. A difference gel electrophoresis study on thylakoids isolated from poplar leaves reveals a negative impact of ozone exposure on membrane proteins.

    Science.gov (United States)

    Bohler, Sacha; Sergeant, Kjell; Hoffmann, Lucien; Dizengremel, Pierre; Hausman, Jean-Francois; Renaut, Jenny; Jolivet, Yves

    2011-07-01

    Populus tremula L. x P. alba L. (Populus x canescens (Aiton) Smith), clone INRA 717-1-B4, saplings were subjected to 120 ppb ozone exposure for 28 days. Chloroplasts were isolated, and the membrane proteins, solubilized using the detergent 1,2-diheptanoyl-sn-glycero-3-phosphocholine (DHPC), were analyzed in a difference gel electrophoresis (DiGE) experiment comparing control versus ozone-exposed plants. Extrinsic photosystem (PS) proteins and adenosine triphosphatase (ATPase) subunits were detected to vary in abundance. The general trend was a decrease in abundance, except for ferredoxin-NADP(+) oxidoreductase (FNR), which increased after the first 7 days of exposure. The up-regulation of FNR would increase NAPDH production for reducing power and detoxification inside and outside of the chloroplast. Later on, FNR and a number of PS and ATPase subunits decrease in abundance. This could be the result of oxidative processes on chloroplast proteins but could also be a way to down-regulate photochemical reactions in response to an inhibition in Calvin cycle activity.

  13. Bright Light Delights: Effects of Daily Light Exposure on Emotions, Restactivity Cycles, Sleep and Melatonin Secretion in Severely Demented Patients.

    Science.gov (United States)

    Münch, Mirjam; Schmieder, Michael; Bieler, Katharina; Goldbach, Rolf; Fuhrmann, Timo; Zumstein, Naomi; Vonmoos, Petra; Scartezzini, Jean-Louis; Wirz-Justice, Anna; Cajochen, Christian

    2017-01-01

    We tested whether the effects of a dynamic lighting system are superior to conventional lighting on emotions, agitation behaviour, quality of life, melatonin secretion and circadian restactivity cycles in severely demented patients. As a comparison, an age matched control patient group was exposed to conventional lighting. For none of the output measures were significant differences between the two lighting conditions found during the 8 study weeks in fall/winter. Thus, we divided the patient cohort (n = 89) into two groups, solely based on the median of their daily individual light exposure. Patients with higher average daily light exposure (>417 lx) showed significantly longer emotional expressions of pleasure and alertness per daily observations than patients with lower daily light exposure. Moreover, they had a higher quality of life, spent less time in bed, went to bed later and initiated their sleep episodes later, even though the two groups did not differ with respect to age, severity of cognitive impairment and mobility. In general, men were more agitated, had shorter sleep with more wake episodes, had a lower circadian amplitude of relative rest-wake activity and interdaily circadian stability than women. In particular, lower daily light exposures significantly predicted lower circadian amplitudes of rest-activity cycles in men but not in women. This may indicate sex specific susceptibility to daily light exposures for rest-activity regulation in older demented patients. Our results provide evidence that a higher daily light exposure has beneficial effects on emotions and thus improved quality of life in a severely demented patient group. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. The effects of ozone exposure and associated injury mechanisms on the central nervous system.

    Science.gov (United States)

    Martínez-Lazcano, Juan Carlos; González-Guevara, Edith; del Carmen Rubio, María; Franco-Pérez, Javier; Custodio, Verónica; Hernández-Cerón, Miguel; Livera, Carlos; Paz, Carlos

    2013-01-01

    Ozone (O3) is a component of photochemical smog, which is a major air pollutant and demonstrates properties that are harmful to health because of the toxic properties that are inherent to its powerful oxidizing capabilities. Environmental O3 exposure is associated with many symptoms related to respiratory disorders, which include loss of lung function, exacerbation of asthma, airway damage, and lung inflammation. The effects of O3 are not restricted to the respiratory system or function - adverse effects within the central nervous system (CNS) such as decreased cognitive response, decrease in motor activity, headaches, disturbances in the sleep-wake cycle, neuronal dysfunctions, cell degeneration, and neurochemical alterations have also been described; furthermore, it has also been proposed that O3 could have epigenetic effects. O3 exposure induces the reactive chemical species in the lungs, but the short half-life of these chemical species has led some authors to attribute the injurious mechanisms observed within the lungs to inflammatory processes. However, the damage to the CNS induced by O3 exposure is not well understood. In this review, the basic mechanisms of inflammation and activation of the immune system by O3 exposure are described and the potential mechanisms of damage, which include neuroinflammation and oxidative stress, and the signs and symptoms of disturbances within the CNS caused by environmental O3 exposure are discussed.

  15. Solar dynamics influence on the atmospheric ozone

    International Nuclear Information System (INIS)

    Gogosheva, T.; Grigorieva, V.; Mendeva, B.; Krastev, D.; Petkov, B.

    2007-01-01

    A response of the atmospheric ozone to the solar dynamics has been studied using the total ozone content data, taken from the satellite experiments GOME on ERS-2 and TOMS-EP together with data obtained from the ground-based spectrophotometer Photon operating in Stara Zagora, Bulgaria during the period 1999-2005. We also use data from surface ozone observations performed in Sofia, Bulgaria. The solar activity was characterized by the sunspot daily numbers W, the solar radio flux at 10.7 cm (F10.7) and the MgII wing-to-core ratio solar index. The impact of the solar activity on the total ozone has been investigated analysing the ozone response to sharp changes of these parameters. Some of the examined cases showed a positive correlation between the ozone and the solar parameters, however, a negative correlation in other cases was found. There were some cases when the sharp increases of the solar activity did not provoke any ozone changes. The solar radiation changes during an eclipse can be considered a particular case of the solar dynamics as this event causes a sharp change of irradiance within a comparatively short time interval. The results of both - the total and surface ozone measurements carried out during the eclipses on 11 August 1999, 31 May 2003 and 29 March 2006 are presented. It was found that the atmospheric ozone behavior shows strong response to the fast solar radiation changes which take place during solar eclipse. (authors)

  16. Risk assessments for forest trees: The performance of the ozone flux versus the AOT concepts

    International Nuclear Information System (INIS)

    Karlsson, P.E.; Braun, S.; Broadmeadow, M.; Elvira, S.; Emberson, L.; Gimeno, B.S.; Le Thiec, D.; Novak, K.; Oksanen, E.; Schaub, M.; Uddling, J.; Wilkinson, M.

    2007-01-01

    Published ozone exposure-response relationships from experimental studies with young trees performed at different sites across Europe were re-analysed in order to test the performance of ozone exposure indices based on AOTX (Accumulated exposure Over a Threshold of X nmol mol -1 ) and AF st Y (Accumulated Stomatal Flux above a threshold of Y nmol m -2 s -1 ). AF st 1.6 was superior, as compared to AOT40, for explaining biomass reductions, when ozone sensitive species with differing leaf morphology were included in the analysis, while this was not the case for less sensitive species. A re-analysis of data with young black cherry trees, subject to different irrigation regimes, indicated that leaf visible injuries were more strongly related to the estimated stomatal ozone uptake, as compared to the ozone concentration in the air. Experimental data with different clones of silver birch indicated that leaf thickness was also an important factor influencing the development of ozone induced leaf visible injury. - Ozone stomatal flux based indices were superior, as compared to AOT40, for explaining biomass reductions and leaf visible injury

  17. Ozone exposure, defoliation of beech (Fagus sylvatica L.) and visible foliar symptoms on native plants in selected plots of South-Western Europe

    International Nuclear Information System (INIS)

    Ferretti, Marco; Calderisi, Marco; Bussotti, Filippo

    2007-01-01

    The relationships between crown defoliation of beech, visible foliar symptoms on native vegetation and ozone exposure were investigated on permanent monitoring sites in South-Western Europe in the years 2000-2002. Relationships between defoliation of beech and O 3 (seasonal mean, 2-week maximum, AOT40) were investigated by means of multiple regression models (11 plots, 1-3 years of data each) and a model based on temporal autocorrelation of defoliation data (14 plots, 1-3 years of data each). Different multiple regression techniques were used. The four models generated (R 2 = 0.71-0.85, explained variance in cross-validation 61-78%) identified several significant predictors of defoliation, with AOT40 (p = 0.008) and foliar content of phosphorous (p = 0.0002-0.0004) being common to all models. The autocorrelation model (R 2 = 0.55; p 35,000 ppbh). O 3 -like visible foliar symptoms were recorded on 65 species at 47% of the common monitoring sites in 2001 and 38% in 2002. No relationship was found between O 3 exposure, frequency of symptomatic sites and frequency of species with symptoms (R 2 = 0.11; p > 0.05). A number of questions related to the ecological and methodological basis of the survey were identified. Inherent sampling and non-sampling errors and multicollinearity of the data suggest great caution when examining results obtained from mensurational, correlative studies. - Ozone AOT40 was identified as a significant predictor of defoliation of beech, but a limited relationship was found between ozone exposure and visible symptoms on native vegetation

  18. California Baseline Ozone Transport Study (CABOTS): Ozonesonde Measurements

    Science.gov (United States)

    Eiserloh, A. J., Jr.; Chiao, S.; Spitze, J.; Cauley, S.; Clark, J.; Roberts, M.

    2016-12-01

    Because the EPA recently lowered the ambient air quality standard for the 8-hr average of ozone (O3) to70 ppbv, California must continue to achieve significant reductions in ozone precursor emissions and prepare for new State Implementation Plans (SIP) to demonstrate how ground-level ambient ozone will be reduced below the new health-based standard. Prior studies suggest that background levels of ozone traveling across the Pacific Ocean can significantly influence surface ozone throughout California, particularly during the spring. Evidence has been presented indicating that background levels of ozone continue to increase in the western United States over the recent few decades, implying more ozone exceedances in the future. To better understand the contributions of the external natural and anthropogenic pollution sources as well as atmospheric processes for surface ozone concentrations in California during the spring and summer months, the California Baseline Ozone Transport Study (CABOTS) has been established. One major goal of CABOTS is to implement near daily ozonesonde measurements along the California Coast to quantify background ozone aloft before entering the State during high ozone season. CABOTS has been ongoing from May through August of 2016 launching ozonesondes from Bodega Bay and Half Moon Bay, California. The temporal progression of ozonesonde measurements and subsequent analysis of the data will be discussed with a focus on the contribution of background ozone to surface ozone sites inland as well as likely origins of layers aloft. Comparisons of current ozonesondes versus prior ozonesonde studies of California will also be performed. A few selected cases of high ozone layers moving onshore from different sources will be discussed as well.

  19. Urbanization and Daily Exposure to Biomass Fuel Smoke Both Contribute to Chronic Bronchitis Risk in a Population with Low Prevalence of Daily Tobacco Smoking.

    Science.gov (United States)

    Miele, Catherine H; Jaganath, Devan; Miranda, J Jaime; Bernabe-Ortiz, Antonio; Gilman, Robert H; Johnson, Caroline M; Diette, Gregory B; Wise, Robert A; Checkley, William

    2016-01-01

    Risk factors beyond tobacco smoking associated with chronic bronchitis are not well understood. We sought to describe the prevalence and risk factors of chronic bronchitis across four distinct settings in Peru with overall low prevalence of tobacco smoking yet varying degrees of urbanization, daily exposure to biomass fuel smoke and living at high altitude. We analyzed data of 2,947 participants from rural and urban Puno, Lima and Tumbes including spirometry, blood samples, anthropometry and administered questionnaires about respiratory symptoms. We used multivariable Poisson regression to assess biologic, socioeconomic and environmental risk factors associated with chronic bronchitis. Overall prevalence of chronic bronchitis was 5.9% (95%CI 5.1%-6.9%) with variation by setting: prevalence was lower in semi-urban Tumbes (1.3%) vs. highly urbanized Lima (8.9%), urban Puno (7.0%) and rural Puno (7.8%; p urbanization (PR = 3.34, 95%CI 2.18-5.11) and daily exposure to biomass fuel smoke (PR = 2.00, 95%CI 1.30-3.07) were all associated with chronic bronchitis. We found important variations in the prevalence of chronic bronchitis across settings. Prevalence increased with both urbanization and with daily exposure to biomass fuel smoke. Having chronic bronchitis was also associated with worse patient-centered outcomes including dyspnea, hospitalization and missed workdays.

  20. Ozone exposure, defoliation of beech (Fagus sylvatica L.) and visible foliar symptoms on native plants in selected plots of South-Western Europe

    Energy Technology Data Exchange (ETDEWEB)

    Ferretti, Marco [Dipartimento di Biologia Vegetale, Universita di Firenze, Piazzale Cascine 28, I-50144 Florence (Italy)]. E-mail: m.ferretti@linnaea.it; Calderisi, Marco [Dipartimento di Biologia Vegetale, Universita di Firenze, Piazzale Cascine 28, I-50144 Florence (Italy)]. E-mail: calderisi@chemiometria.it; Bussotti, Filippo [Dipartimento di Biologia Vegetale, Universita di Firenze, Piazzale Cascine 28, I-50144 Florence (Italy)]. E-mail: filippo.bussotti@unifi.it

    2007-02-15

    The relationships between crown defoliation of beech, visible foliar symptoms on native vegetation and ozone exposure were investigated on permanent monitoring sites in South-Western Europe in the years 2000-2002. Relationships between defoliation of beech and O{sub 3} (seasonal mean, 2-week maximum, AOT40) were investigated by means of multiple regression models (11 plots, 1-3 years of data each) and a model based on temporal autocorrelation of defoliation data (14 plots, 1-3 years of data each). Different multiple regression techniques were used. The four models generated (R {sup 2} = 0.71-0.85, explained variance in cross-validation 61-78%) identified several significant predictors of defoliation, with AOT40 (p = 0.008) and foliar content of phosphorous (p = 0.0002-0.0004) being common to all models. The autocorrelation model (R {sup 2} = 0.55; p < 0.0001) was used to calculate expected defoliation on the basis of the previous year's defoliation, and model predictions were used as an estimate of expected defoliation under constant site and environmental condition. Residuals (predicted-measured) plotted against current AOT40 shows that a possible effect of ozone occurs only at very high AOT40 (>35,000 ppbh). O{sub 3}-like visible foliar symptoms were recorded on 65 species at 47% of the common monitoring sites in 2001 and 38% in 2002. No relationship was found between O{sub 3} exposure, frequency of symptomatic sites and frequency of species with symptoms (R {sup 2} = 0.11; p > 0.05). A number of questions related to the ecological and methodological basis of the survey were identified. Inherent sampling and non-sampling errors and multicollinearity of the data suggest great caution when examining results obtained from mensurational, correlative studies. - Ozone AOT40 was identified as a significant predictor of defoliation of beech, but a limited relationship was found between ozone exposure and visible symptoms on native vegetation.

  1. Ozone and sulphur dioxide effects on leaf water potential of Petunia

    Energy Technology Data Exchange (ETDEWEB)

    Elkiey, T.; Ormrod, D.P.

    1979-01-01

    Three cultivars of Petunia hydrida Vilm., of differing ozone visible injury sensitivity, were exposed to 40 parts per hundred million (pphm) ozone and/or 80 pphm SO/sub 2/ for 4 h to study the relationships of leaf water potential, pollutant exposure, and cultivar sensitivity. Ozone substantially decreased leaf water potential in cv White Cascade but not in cv Capri or White Magic. Sulphur dioxide did not affect leaf water potential but delayed ozone-induced changes. Cultivar sensitivity to ozone-induced changes in leaf water potential was not related to cultivar sensitivity to ozone-induced visible injury.

  2. Effective cloud fractions from the Ozone Monitoring Instrument: theoretical framework and validation

    NARCIS (Netherlands)

    Stammes, P.; Sneep, M.; Haan, de J.F.; Veefkind, J.P.; Wang, P.; Levelt, P.F.

    2008-01-01

    The Dutch-Finnish Ozone Monitoring Instrument (OMI) on board NASA's EOS-Aura satellite is measuring ozone, NO2, and other trace gases with daily global coverage. To correct these trace gas retrievals for the presence of clouds, there are two OMI cloud products, based on different physical processes,

  3. Field responses of Prunus serotina and Asclepias syriaca to ozone around southern Lake Michigan

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, J.P. [U.S. Geological Survey and Institute for Environmental Studies, University of Wisconsin, Madison, WI 53706 (United States)]. E-mail: jpbennet@wisc.edu; Jepsen, E.A. [Bureau of Air Management, Wisconsin Department of Natural Resources, Madison, WI 53707 (United States); Roth, J.A. [Bureau of Air Management, Wisconsin Department of Natural Resources, Madison, WI 53707 (United States)

    2006-07-15

    Higher ozone concentrations east of southern Lake Michigan compared to west of the lake were used to test hypotheses about injury and growth effects on two plant species. We measured approximately 1000 black cherry trees and over 3000 milkweed stems from 1999 to 2001 for this purpose. Black cherry branch elongation and milkweed growth and pod formation were significantly higher west of Lake Michigan while ozone injury was greater east of Lake Michigan. Using classification and regression tree (CART) analyses we determined that departures from normal precipitation, soil nitrogen and ozone exposure/peak hourly concentrations were the most important variables affecting cherry branch elongation, and milkweed stem height and pod formation. The effects of ozone were not consistently comparable with the effects of soil nutrients, weather, insect or disease injury, and depended on species. Ozone SUM06 exposures greater than 13 ppm-h decreased cherry branch elongation 18%; peak 1-h exposures greater than 93 ppb reduced milkweed stem height 13%; and peak 1-h concentrations greater than 98 ppb reduced pod formation 11% in milkweed. - Decreased cherry branch elongation, milkweed stem height and pod production, and foliar injury on both species occurred at sites around southern Lake Michigan at ozone exposures of 13 SUM06 ppm-h and 93-98 ppb peak hourly.

  4. Field responses of Prunus serotina and Asclepias syriaca to ozone around southern Lake Michigan

    International Nuclear Information System (INIS)

    Bennett, J.P.; Jepsen, E.A.; Roth, J.A.

    2006-01-01

    Higher ozone concentrations east of southern Lake Michigan compared to west of the lake were used to test hypotheses about injury and growth effects on two plant species. We measured approximately 1000 black cherry trees and over 3000 milkweed stems from 1999 to 2001 for this purpose. Black cherry branch elongation and milkweed growth and pod formation were significantly higher west of Lake Michigan while ozone injury was greater east of Lake Michigan. Using classification and regression tree (CART) analyses we determined that departures from normal precipitation, soil nitrogen and ozone exposure/peak hourly concentrations were the most important variables affecting cherry branch elongation, and milkweed stem height and pod formation. The effects of ozone were not consistently comparable with the effects of soil nutrients, weather, insect or disease injury, and depended on species. Ozone SUM06 exposures greater than 13 ppm-h decreased cherry branch elongation 18%; peak 1-h exposures greater than 93 ppb reduced milkweed stem height 13%; and peak 1-h concentrations greater than 98 ppb reduced pod formation 11% in milkweed. - Decreased cherry branch elongation, milkweed stem height and pod production, and foliar injury on both species occurred at sites around southern Lake Michigan at ozone exposures of 13 SUM06 ppm-h and 93-98 ppb peak hourly

  5. Fluid cognitive ability is associated with greater exposure and smaller reactions to daily stressors.

    Science.gov (United States)

    Stawski, Robert S; Almeida, David M; Lachman, Margie E; Tun, Patricia A; Rosnick, Christopher B

    2010-06-01

    The authors of this study investigated whether fluid cognitive ability predicts exposure and emotional reactivity to daily stressors. A national sample of adults from the Midlife in the United States study and the National Study of Daily Experiences (N = 1,202) who had a mean age of 57 years (SD = 12; 56% women, 44% men) completed positive and negative mood reports as well as a stressor diary on 8 consecutive evenings via telephone. Participants also completed a telephone-based battery of tests measuring fluid cognitive ability. Higher levels of fluid cognitive ability were associated with greater exposure to work- and home-related overload stressors. Possessing higher levels of fluid cognitive ability was associated with smaller stressor-related increases in negative mood, primarily for interpersonal tensions and network stressors, and smaller stressor-related decreases in positive mood for interpersonal tensions. Furthermore, fluid cognitive ability was unrelated to subjective severity ratings of the stressors reported. Discussion focuses on the role of fluid cognitive ability in daily stress processes. (c) 2010 APA, all rights reserved).

  6. Ozone sonde cell current measurements and implications for observations of near-zero ozone concentrations in the tropical upper troposphere

    Directory of Open Access Journals (Sweden)

    H. Vömel

    2010-04-01

    Full Text Available Laboratory measurements of the Electrochemical Concentration Cell (ECC ozone sonde cell current using ozone free air as well as defined amounts of ozone reveal that background current measurements during sonde preparation are neither constant as a function of time, nor constant as a function of ozone concentration. Using a background current, measured at a defined timed after exposure to high ozone may often overestimate the real background, leading to artificially low ozone concentrations in the upper tropical troposphere, and may frequently lead to operator dependent uncertainties. Based on these laboratory measurements an improved cell current to partial pressure conversion is proposed, which removes operator dependent variability in the background reading and possible artifacts in this measurement. Data from the Central Equatorial Pacific Experiment (CEPEX have been reprocessed using the improved background treatment based on these laboratory measurements. In the reprocessed data set near-zero ozone events no longer occur. At Samoa, Fiji, Tahiti, and San Cristóbal, nearly all near-zero ozone concentrations occur in soundings with larger background currents. To a large extent, these events are no longer observed in the reprocessed data set using the improved background treatment.

  7. Ozone-induced airway hyperresponsiveness in patients with asthma: role of neutrophil-derived serine proteinases.

    Science.gov (United States)

    Hiltermann, T J; Peters, E A; Alberts, B; Kwikkers, K; Borggreven, P A; Hiemstra, P S; Dijkman, J H; van Bree, L A; Stolk, J

    1998-04-01

    Proteinase inhibitors may be of potential therapeutic value in the treatment of respiratory diseases such as chronic obstructive pulmonary disease (COPD) or asthma. Our aim was to study the role of neutrophils, and neutrophil-derived serine proteinases in an acute model in patients with asthma. Exposure to ozone induces an acute neutrophilic inflammatory reaction accompanied by an increase in airway hyperresponsiveness. It is thought that these two effects of ozone are linked, and that neutrophil-derived serine proteinases (i.e. elastase) may play a role in the ozone-induced airway hyperresponsiveness. Therefore, we examined the effect of recombinant antileukoprotease (rALP), one of the major serine proteinase inhibitors in the lung, on ozone-induced changes in airway hyperresponsiveness in this model. We observed that 16 h after exposure to ozone, airway hyperresponsiveness to methacholine was increased both following placebo and rALP treatment. There was no significant difference between placebo and rALP treatment (change in area under the dose-response curve to methacholine: 117.3+/-59.0 vs 193.6+/-59.6 % fall x DD; p=.12). Moreover, the immediate decrease in FEV1 after ozone exposure was not significantly different between the two groups (placebo: -29.6+/-6.7%; rALP: -20.9+/-3.8%; p=.11). In addition, no significant differences were observed in plasma levels of fibrinogen degradation products generated by neutrophil serine proteinases before and after exposure to ozone. We conclude that neutrophil-derived serine proteinases are not important mediators for ozone-induced hyperresponsiveness.

  8. Protective Role of Eosinophils and TNFa after Ozone Inhalation.

    Science.gov (United States)

    Fryer, Allison D; Jacoby, David B; Wicher, Sarah A

    2017-03-01

    Exposure to ozone induces deleterious responses in the airways that include shortness of breath, inflammation, and bronchoconstriction. People with asthma have increased airway sensitivity to ozone and other irritants. Dr. Allison Fryer and colleagues addressed how exposure to ozone affects the immune and physiological responses in guinea pigs. Guinea pigs are considered a useful animal model for studies of respiratory and physiological responses in humans; their response to airborne allergens is similar to that in humans and shares some features of allergic asthma. Fryer and colleagues had previously observed that within 24 hours of exposure, ozone not only induced bronchoconstriction but also stimulated the production of new cells in the bone marrow, where all white blood cells develop. As a result of ozone exposure, increased numbers of newly synthesized white blood cells, particularly eosinophils, moved into the blood and lungs. The central hypothesis of the current study was that newly synthesized eosinophils recruited to the lungs 3 days after ozone exposure were beneficial to the animals because they reduced ozoneinduced bronchoconstriction. The investigators also hypothesized that the beneficial effect seen in normal (nonsensitized) animals was lost in animals that had been injected with an allergen, ovalbumin (sensitized). They also planned to explore the effects of inhibitors of certain cytokines (cellsignaling molecules). Immune responses in sensitized animals are dominated by a Th2 pattern, which is characterized by the synthesis of cytokines (interleukin [IL]-4, IL-5, and IL-13) and the Th2 subset of CD4+ T lymphocytes and the cells they activate (predominantly eosinophils, and B lymphocytes that switch to making immunoglobulin E [IgE]). Thus, sensitized animals were used as a model of allergic humans, whose immune responses tend to be dominated by IgE. Fryer and colleagues exposed normal and sensitized (allergic) guinea pigs to 2 ppm ozone or filtered

  9. Ozone modelling in Eastern Austria

    Energy Technology Data Exchange (ETDEWEB)

    Stohl, A.; Wotawa, G.; Kromp-Kolb, H. [Univ. of Agriculture, Vienna (Austria). Inst. of Meteorology and Physics; Winiwater, W. [Austrian Research Centre, Seibersdorf (Austria); Baumann, R.; Spangl, W. [Federal Environmental Agency, Vienna (Austria)

    1995-12-31

    High ozone concentrations are frequently observed in Eastern Austria, often exceeding local as well as international health standards, both for short-term as well as for long-term exposures. The maximum concentrations are produced in urban plumes, e.g. of the city of Vienna, whereas regional-scale transport and production of ozone is more important for the long-term concentrations. The Pannonian Ozone Project (POP) is an Austrian research initiative to model photochemical processes on a regional as well as on a local scale with a Lagrangian model to better understand the mechanisms leading to the high ozone concentrations and to develop abatement strategies. Up to now, focus has been on the regional scale. Aircraft, tethered balloon, tetroon and intensified ground measurements are carried out to validate the model. Although the major measurement campaign will be held in summer 1995, first results from a measurement campaign in summer 1994 are already available

  10. Products and mechanisms of the reaction of gas phase ozone with organic colorants

    Energy Technology Data Exchange (ETDEWEB)

    Grosjean, D. (DGA, Inc., Ventura, CA (USA)); Druzik, J.R. (Getty Conservation Institute, Marina del Rey, CA (USA)); Sensharma, D.K. (Univ. of California, Los Angeles (USA)); Whitmore, P.M.; DeMoor, C.P.; Cass, G.R. (California Institute of Technology, Pasadena (USA))

    1988-09-01

    Studies carried out in this laboratory have shown that many artists organic colorants fade substantially when exposed to ozone in the dark. These studies typically involved pigment exposure for 12 weeks to purified air containing 0.3-0.4 ppm of ozone at ambient temperature and humidity. These laboratory conditions are equivalent to about six years of exposure inside a typical air-conditioned building in Los Angeles, and the observed fading is therefore directly relevant to possible damage to works of arts in museum settings. Organic colorants that were most ozone-fugitive included natural colorants, such as curcumin and indigo, as well as modern synthetic colorants such as alizarin lakes and triphenylmethane dyes. Thus, these colorants were selected for further study with emphasis on the nature of the reaction products. Exposures were carried out on different substrates including watercolor paper, cellulose, silica gel, and Teflon. The experiments involved long-term exposure to low levels of ozone (e.g. {approximately} 0.3 ppm for 90 days) or shorter-term exposure to higher ozone concentrations (e.g. 10 ppm for 24 hours). Exposed and control samples, along with solvent and substrate blanks, were analyzed by mass spectrometry using a Kratos Scientific Instruments MS25 hexapole mass spectrometer operated in either methane chemical ionization (CI) or electron impact (EI) modes.

  11. Driver exposure to volatile organic compounds, CO, ozone, and NO2 under different driving conditions

    International Nuclear Information System (INIS)

    Changchuan Chan; Oezkaynak, H.; Spengler, J.D.; Sheldon, L.

    1991-01-01

    The in-vehicle concentrations of 24 gasoline-related volatile organic compounds (VOCs) and three criteria air pollutants, ozone, carbon monoxide, and nitrogen dioxide, were measured in the summer of 1988, in Raleigh, NC. Two four-door sedan of different ages were used to evaluate in-vehicle concentrations of these compounds under different driving conditions. Factors that could influence driver exposure, such as different traffic patterns, car model, vehicle ventilation conditions, and driving periods, were evaluated. Isopentane was the most abundant aliphatic hydrocarbon and toluene was the most abundant aromatic VOC measured inside the vehicles. In-vehicle VOC and CO concentrations were highest for the urban roadway, second highest for the interstate highway, and lowest for the rural road. The median concentration ratio of urban/interstate/rural for each VOC was about 10/6/1. No differences in in-vehicle VOC concentrations were found between morning and afternoon rush hour driving, but higher in-vehicle ozone and NO 2 concentrations were found during afternoon driving. In-vehicle VOC levels were lowest with the air conditioner on and highest when the vent was open with the fan on. The in-vehicle/car exterior concentration ratio for VOCs, CO, and NO 2 was slightly higher than 1. The VOC concentration measured by a pedestrian on the urban sidewalk was lower than the in-vehicle measurements but higher than the fixed-site measurements but higher than the fixed-site measurements on urban roadways 50 m from streets. The VOC measurements were positively correlated with the CO measurement and negatively correlated with the ozone measurement

  12. Impacts of ozone-vegetation coupling and feedbacks on global air quality, ecosystems and food security

    Science.gov (United States)

    Tai, A. P. K.

    2016-12-01

    Surface ozone is an air pollutant of significant concerns due to its harmful effects on human health, vegetation and crop productivity. Chronic ozone exposure is shown to reduce photosynthesis and interfere with gas exchange in plants, thereby influencing surface energy balance and biogeochemical fluxes with important ramifications for climate and atmospheric composition, including possible feedbacks onto ozone itself that are not well understood. Ozone damage on crops has been well documented, but a mechanistic understanding is not well established. Here we present several results pertaining to the effects of ozone-vegetation coupling on air quality, ecosystems and agriculture. Using the Community Earth System Model (CESM), we find that inclusion of ozone damage on plants reduces the global land carbon sink by up to 5%, while simulated ozone is enhanced by up to 6 ppbv North America, Europe and East Asia. This strong positive feedback on ozone air quality via ozone-vegetation coupling arises mainly from reduced stomatal conductance, which induces two feedback pathways: 1) reduced dry deposition and ozone uptake; and 2) reduced evapotranspiration that enhances vegetation temperature and thus isoprene emission. Using the same ozone-vegetation scheme in a crop model within CESM, we further examine the impacts of historical ozone exposure on global crop production. We contrast our model results with a separate statistical analysis designed to characterize the spatial variability of crop-ozone-temperature relationships and account for the confounding effect of ozone-temperature covariation, using multidecadal global datasets of crop yields, agroclimatic variables and ozone exposures. We find that several crops (especially C4 crops such as maize) exhibit stronger sensitivities to ozone than found by field studies or in CESM simulations. We also find a strong anticorrelation between crop sensitivities and average ozone levels, reflecting biological adaptive ozone

  13. Ozone injury increases infection of geranium leaves by Botrytis cinerea

    Energy Technology Data Exchange (ETDEWEB)

    Manning, W.J.; Feder, W.A.; Perkins, I.

    1970-04-01

    Detached and attached, inoculated and noninoculated, ozone-injured and noninjured leaves from the lower, middle, and terminal regions of plants of geranium cultivars Enchantress and White Mountain were observed for infection by Botrytis cinerea. Previous exposure to ozone did not appreciably influence the susceptibility of leaves of either geranium cultivar to infection by B. cinerea, unless there was visible ozone injury. Ozone-injured, necrotic tissues on older attached and detached geranium leaves of both cultivars served as infection courts for B. cinerea. 14 references, 1 table.

  14. Observing Tropospheric Ozone From Space

    Science.gov (United States)

    Fishman, Jack

    2000-01-01

    The importance of tropospheric ozone embraces a spectrum of relevant scientific issues ranging from local environmental concerns, such as damage to the biosphere and human health, to those that impact global change questions, Such is climate warming. From an observational perspective, the challenge is to determine the tropospheric ozone global distribution. Because its lifetime is short compared with other important greenhouse gases that have been monitored over the past several decades, the distribution of tropospheric ozone cannot be inferred from a relatively small set of monitoring stations. Therefore, the best way to obtain a true global picture is from the use of space-based instrumentation where important spatial gradients over vast ocean expanses and other uninhabited areas can be properly characterized. In this paper, the development of the capability to measure tropospheric ozone from space over the past 15 years is summarized. Research in the late 1980s successfully led to the determination of the climatology of tropospheric ozone as a function of season; more recently, the methodology has improved to the extent where regional air pollution episodes can be characterized. The most recent modifications now provide quasi-global (50 N) to 50 S) maps on a daily basis. Such a data set would allow for the study of long-range (intercontinental) transport of air pollution and the quantification of how regional emissions feed into the global tropospheric ozone budget. Future measurement capabilities within this decade promise to offer the ability to provide Concurrent maps of the precursors to the in situ formation of tropospheric ozone from which the scientific community will gain unprecedented insight into the processes that control global tropospheric chemistry

  15. Acute Ozone (O3) Exposure Accelerates Diet-Induced Pulmonary Injury and Metabolic Alterations in a Rat Model of Type II Diabetes

    Science.gov (United States)

    Abstract for Society of Toxicology, March 22-25, 2015, San Diego, CAAcute Ozone (O3) Exposure Accelerates Diet-Induced Pulmonary Injury and Metabolic Alterations in a Rat Model of Type II DiabetesS.J. Snow1,3, D. Miller2, V. Bass2, M. Schladweiler3, A. Ledbetter3, J. Richards3, C...

  16. Passive sampling of ambient ozone by solid phase microextraction with on-fiber derivatization

    International Nuclear Information System (INIS)

    Lee, I-S.; Tsai, S.-W.

    2008-01-01

    The solid phase microextraction (SPME) device with the polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber was used as a passive sampler for ambient ozone. Both O-2,3,4,5,6-(pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) and 1,2-di-(4-pyridyl)ethylene (DPE) were loaded onto the fiber before sampling. The SPME fiber assembly was then inserted into a PTFE tubing as a passive sampler. Known concentrations of ozone around the ambient ground level were generated by a calibrated ozone generator. Laboratory validations of the SPME passive sampler with the direct-reading ozone monitor were performed side-by-side in an exposure chamber at 25 deg. C. After exposures, pyriden-4-aldehyde was formed due to the reaction between DPE and ozone. Further on-fiber derivatizations between pyriden-4-aldehyde and PFBHA were followed and the derivatives, oximes, were then determined by portable gas chromatography with electron capture detector. The experimental sampling rate of the SPME ozone passive sampler was found to be 1.10 x 10 -4 cm 3 s -1 with detection limit of 58.8 μg m -3 h -1 . Field validations with both SPME device and the direct-reading ozone monitor were also performed. The correlations between the results from both methods were found to be consistent with r = 0.9837. Compared with other methods, the current designed sampler provides a convenient and sensitive tool for the exposure assessments of ozone

  17. Ozone Sensitivity and Catalase Activity in Pigmented and Non-Pigmented Strains of Serratia Marcescens.

    Science.gov (United States)

    de Ondarza, José

    2017-01-01

    Ozone exposure rapidly leads to bacterial death, making ozone an effective disinfectant in food industry and health care arena. However, microbial defenses may moderate this effect and play a role in the effective use of oxidizing agents for disinfection. Serratia marcescens is an opportunistic pathogen, expressing genes differentially during infection of a human host. A better understanding of regulatory systems that control expression of Serratia 's virulence genes and defenses is therefore valuable. Here, we investigated the role of pigmentation and catalase in Serratia marcescens on survival to ozone exposure. Pigmented and non-pigmented strains of Serratia marcescens were cultured to exponential or stationary phase and exposed to 5 ppm of gaseous ozone for 2.5 - 10 minutes. Survival was calculated via plate counts. Catalase activity was measured photometrically and tolerance to hydrogen peroxide was assayed by disk-diffusion. Exposure of S. marcescens to 5 ppm gaseous ozone kills > 90% of cells within 10 minutes in a time and concentration-dependent manner. Although pigmented Serratia (grown at 28°C) survived ozonation better than unpigmented Serratia (grown at 35°C), non-pigmented mutant strains of Serratia had similar ozone survival rates, catalase activity and H 2 O 2 tolerance as wild type strains. Rather, ozone survival and catalase activity were elevated in 6 hour cultures compared to 48 hour cultures. Our studies did not bear out a role for prodigiosin in ozone survival. Rather, induction of oxidative stress responses during exponential growth increased both catalase activity and ozone survival in both pigmented and unpigmented S. marcescens .

  18. Influence of wildfires on the variability and trend of ozone concentrations in the U.S. Intermountain West

    Science.gov (United States)

    Lu, Xiao; Zhang, Lin; Zhao, Yuanhong; Yue, Xu

    2016-04-01

    Wildfires are important sources of ozone by emitting large amounts of NOx and NMVOC, main ozone precursors at both global and regional scales. Their influences on ozone in the U.S. Intermountain West have recently received much interest because surface ozone concentrations over that region showed an increasing trend in the past two decades likely due to increasing wildfire emissions in a warming climate. Here we use the Lagrangian particle dispersion model (FLEXPART) as well as the GEOS-Chem chemical transport model to estimate wildfires' contribution on summer (June, July and August; JJA) ozone concentration variations, trends, and extremely high ozone events over the US Intermountain West for the past 22 years (1989-2010). We combine the resident time estimated from the FLEXPART 5-day backward trajectories and a high-resolution fire inventory to define a fire index representing the impact of wildfires on ozone concentration at a particular site for each day of summers 1989-2010. Over 26,000 FLEXPART back-trajectories are conducted for the whole time period and for 13 CASTNet surface monitoring sites. We build a stepwise multiple linear regression (SMLR) model of daily ozone concentrations using fire index and other meteorological variables for each site. The SMLR models explain 53% of the ozone variations (ranging from 12% to 68% for each site). We show that ozone produced from wildfires (calculated from SMLR model) are of high variability at daily scale (ranging from 0.1 ppbv to 20.7 ppbv), but are averaged to lower values of about 0.25-3.5 ppbv for summer mean. We estimate that wildfires magnify inter-annual variations of the regional mean summer ozone for about 32%, compared to the result with wildfires impact excluded from the SMLR model. Wildfire ozone enhancements increase at a rate of 0.04 ppbv per year, accouting for about 20% of the regional summer ozone trend during 1989-2010. Removing wildfires' impact would reduce 35% (46%) of the high-ozone days with

  19. Evaluation of sorghum flour functionality and quality characteristics of gluten-free bread and cake as influenced by ozone treatment.

    Science.gov (United States)

    Marston, Kathryn; Khouryieh, Hanna; Aramouni, Fadi

    2015-12-01

    Commercially milled food-grade sorghum flour was subjected to ozone at the rate of 0.06 L/min for 15, 30, and 45 min. The pH of ozone-treated flour decreased as exposure time increased. The L* (lightness) values of sorghum flour significantly increased (p cake volume significantly increased as ozonation time increased. Additionally, longer ozonation exposure times increased cells per slice area, lightness, and slice brightness values in gluten-free cakes while reducing crumb firmness. Despite improving lightness and slice brightness values, ozonation did not significantly increase the specific volume of gluten-free batter-based bread. While ozonation improved the volume and texture in cakes, it did not have the same positive effects on gluten-free bread. Bread made from ozonated sorghum flour had an open ragged structure with equivalent volume to the control flour. In both applications, the increased brightness and lightness values due to ozone exposure is recommended to increase the acceptability of sorghum products. © The Author(s) 2014.

  20. Adrenal-derived stress hormones modulate ozone-induced lung injury and inflammation

    Science.gov (United States)

    Ozone-induced systemic effects are modulated through activation of the neuro-hormonal stress response pathway. Adrenal demedullation (DEMED)or bilateral total adrenalectomy (ADREX) inhibits systemic and pulmonary effect of acute ozone exposure. To understand the influence of adre...

  1. Persistent polar depletion of stratospheric ozone and emergent mechanisms of ultraviolet radiation-mediated health dysregulation.

    Science.gov (United States)

    Dugo, Mark A; Han, Fengxiang; Tchounwou, Paul B

    2012-01-01

    Year 2011 noted the first definable ozone "hole" in the Arctic region, serving as an indicator to the continued threat of dangerous ultraviolet radiation (UVR) exposure caused by the deterioration of stratospheric ozone in the northern hemisphere. Despite mandates of the Montreal Protocol to phase out the production of ozone-depleting chemicals (ODCs), the relative stability of ODCs validates popular notions of persistent stratospheric ozone for several decades. Moreover, increased UVR exposure through stratospheric ozone depletion is occurring within a larger context of physiologic stress and climate change across the biosphere. In this review, we provide commentaries on stratospheric ozone depletion with relative comparisons between the well-known Antarctic ozone hole and the newly defined ozone hole in the Arctic. Compared with the Antarctic region, the increased UVR exposure in the Northern Hemisphere poses a threat to denser human populations across North America, Europe, and Asia. In this context, we discuss emerging targets of UVR exposure that can potentially offset normal biologic rhythms in terms of taxonomically conserved photoperiod-dependent seasonal signaling and entrainment of circadian clocks. Consequences of seasonal shifts during critical life history stages can alter fitness and condition, whereas circadian disruption is increasingly becoming associated as a causal link to increased carcinogenesis. We further review the significance of genomic alterations via UVR-induced modulations of phase I and II transcription factors located in skin cells, the aryl hydrocarbon receptor (AhR), and the nuclear factor (erythroid-derived 2)-related factor 2 (Nrf2), with emphasis on mechanism that can lead to metabolic shifts and cancer. Although concern for adverse health consequences due to increased UVR exposure are longstanding, recent advances in biochemical research suggest that AhR and Nrf2 transcriptional regulators are likely targets for UVR

  2. Effect of ozone on photosynthesis and respiration of Scenedesmus obtusiusculus Chod. , with a general discussion of effects of air pollutants in plants

    Energy Technology Data Exchange (ETDEWEB)

    Verkroost, M

    1974-01-01

    In the present study the mode of action of the air pollutant ozone was investigated by studying its effects on photosynthesis, respiration and some biochemical and structural properties of the unicellular alga, Scenedesmus obtusiusculus CHOD. The extensive literature on the effects of the most important air pollutant gases SO/sub 2/, HF, NO/sub 2/, PAN and O/sub 3/ on the processes of photosynthesis and respiration is reviewed, while possible modes of action of each of these gases are discussed. The procedure for ozone exposure is extensively described. It is shown that photosynthesis and dark respiration are inhibited by previous exposure of the cell suspensions to ozone; the inhibition is increased with the duration of exposure and with temperature during exposure. The effect of an ozone treatment is increased by light during the exposure, and consequently, photosynthesis appears more inhibited in as much as the light-intensity during the preceding exposure to ozone was higher. It is shown that the chlorophyll content decreases by exposure to ozone; the decrease is more pronounced after exposure in the light than after exposure in the dark. It appeared in a preliminary study that there is a substantial loss of lipid in ozone-exposed algae, and there are indications that this in mainly due to oxidation of the unsaturated fatty acid, linoleic acid. A preliminary study showed that there is a very small loss of protein content in ozone-exposed algae, which may be ascribed mainly to oxidation of the acid component serine, and of an unidentified alkaline compound. In ozone exposed algae, ultrastructural changes are observed. 181 references, 21 figures, 11 tables.

  3. A passive sampler for atmospheric ozone

    International Nuclear Information System (INIS)

    Grosjean, D.; Hisham, M.W.M.

    1992-01-01

    A simple, cost-effective passive sampler has been developed for the determination of atmospheric ozone. This passive sampler is based on a colorant which fades upon reaction with ozone, whose concentration can be determined by reflectance measurement of the color change. Direct, on-site measurements are possible, and no chemical analyses are needed. Sampler design and validation studies have been carried out and included quantitative determination of color change vs exposure time (1-8 days), color change vs. ozone concentration (30-350 ppb), and response to changes in sampler configuration that modify the passive sampling rate. With indigo carmine as the colorant, the detection limits are 30 ppb. day and 120 ppb. day using a plastic grid and Teflon filter, respectively, as diffusion barriers. Interferences from nitrogen dioxide, formaldehyde and peroxyacetyl nitrate are 15, 4 and 16%, respectively, thus resulting in a negligible bias when measuring ozone in ambient air

  4. Short-term respiratory effects of 0. 12 ppm ozone exposure in volunteers with chronic obstructive pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Linn, W.S.; Fischer, D.A.; Medway, D.A.; Anzar, U.T.; Spier, C.E.; Valencia, L.M.; Venet, T.G.; Hackney, J.D.

    1982-06-01

    Twenty-five volunteers with chronic obstructive pulmonary disease of mild to moderately severe degree underwent 1-h exposures to 0.12 ppm ozone (O/sub 2/) in purified air with intermittent mild exercise. Their responses were assessed in terms of forced expiratory performance, ear oximetry, and reported symptoms. Control studied consisted of similar exposures to purified air alone. Control studies were separated from O/sub 2/ exposures by 1 month, and the order was randomized. All studies took place in a controlled-environment chamber, and were preceded by approximately 1 h of rest in a purified-air environment. No significant disturbances in forced expiratory performance or symptoms attributable to O/sub 2/ exposure were found. A slight but significant tendency to decreased arterial hemoglobin oxygen saturation (SaO/sub 2/) during exercise in O/sub 2/ was observed. The decrement in SaO/sub 2/ with O/sub 2/ relative to clean air (mean 1.3%) was near the limit of resolution of the ear oximeter test and was detected by signal averaging, thus its physiologic or clinical significance is uncertain.

  5. Limonene and its ozone-initiated reaction products attenuate allergic lung inflammation in mice.

    Science.gov (United States)

    Hansen, Jitka S; Nørgaard, Asger W; Koponen, Ismo K; Sørli, Jorid B; Paidi, Maya D; Hansen, Søren W K; Clausen, Per Axel; Nielsen, Gunnar D; Wolkoff, Peder; Larsen, Søren Thor

    2016-11-01

    Inhalation of indoor air pollutants may cause airway irritation and inflammation and is suspected to worsen allergic reactions. Inflammation may be due to mucosal damage, upper (sensory) and lower (pulmonary) airway irritation due to activation of the trigeminal and vagal nerves, respectively, and to neurogenic inflammation. The terpene, d-limonene, is used as a fragrance in numerous consumer products. When limonene reacts with the pulmonary irritant ozone, a complex mixture of gas and particle phase products is formed, which causes sensory irritation. This study investigated whether limonene, ozone or the reaction mixture can exacerbate allergic lung inflammation and whether airway irritation is enhanced in allergic BALB/cJ mice. Naïve and allergic (ovalbumin sensitized) mice were exposed via inhalation for three consecutive days to clean air, ozone, limonene or an ozone-limonene reaction mixture. Sensory and pulmonary irritation was investigated in addition to ovalbumin-specific antibodies, inflammatory cells, total protein and surfactant protein D in bronchoalveolar lavage fluid and hemeoxygenase-1 and cytokines in lung tissue. Overall, airway allergy was not exacerbated by any of the exposures. In contrast, it was found that limonene and the ozone-limonene reaction mixture reduced allergic inflammation possibly due to antioxidant properties. Ozone induced sensory irritation in both naïve and allergic mice. However, allergic but not naïve mice were protected from pulmonary irritation induced by ozone. This study showed that irritation responses might be modulated by airway allergy. However, aggravation of allergic symptoms was observed by neither exposure to ozone nor exposure to ozone-initiated limonene reaction products. In contrast, anti-inflammatory properties of the tested limonene-containing pollutants might attenuate airway allergy.

  6. Ozone slows stomatal response to light and leaf wounding in a Mediterranean evergreen broadleaf, Arbutus unedo

    Energy Technology Data Exchange (ETDEWEB)

    Paoletti, Elena [Istituto Protezione Piante, Consiglio Nazionale delle Ricerche, Via Madonna del Piano, I-50019 Sesto Fiorentino (Italy)]. E-mail: e.paoletti@ipp.cnr.it

    2005-04-01

    The effect of a 90-d ozone exposure (charcoal-filtered air or 110 nmol mol{sup -1} O{sub 3}) on stomatal conductance (g{sub s}) was investigated in the Mediterranean evergreen broadleaf Arbutus unedo L. Ozone did not significantly reduce midday steady-state g{sub s} compared to controls. However, it slowed stomatal response to abrupt reduction of light intensity and to increasing water stress, applied by severing the leaf midrib. Ozone slowed stomatal closure, rather than aperture. Nevertheless, vein-cutting did not allow ozonated leaves to reach the pre-injury g{sub s} levels, like controls did, suggesting re-opening was still, slowly in progress. The sluggish behaviour was recorded 10 days after cessation of O{sub 3} exposure ('memory effect') and may affect stomatal control in response to sunflecks and leaf wounding. Mediterranean evergreen broadleaves are regarded as tolerant to O{sub 3} exposure. Nevertheless, measurements of steady-state g{sub s} at midday may not account for altered stomatal responses to stressors. - In response to ozone exposure, stomata were slower in closing rather than in opening.

  7. Ozone slows stomatal response to light and leaf wounding in a Mediterranean evergreen broadleaf, Arbutus unedo

    International Nuclear Information System (INIS)

    Paoletti, Elena

    2005-01-01

    The effect of a 90-d ozone exposure (charcoal-filtered air or 110 nmol mol -1 O 3 ) on stomatal conductance (g s ) was investigated in the Mediterranean evergreen broadleaf Arbutus unedo L. Ozone did not significantly reduce midday steady-state g s compared to controls. However, it slowed stomatal response to abrupt reduction of light intensity and to increasing water stress, applied by severing the leaf midrib. Ozone slowed stomatal closure, rather than aperture. Nevertheless, vein-cutting did not allow ozonated leaves to reach the pre-injury g s levels, like controls did, suggesting re-opening was still, slowly in progress. The sluggish behaviour was recorded 10 days after cessation of O 3 exposure ('memory effect') and may affect stomatal control in response to sunflecks and leaf wounding. Mediterranean evergreen broadleaves are regarded as tolerant to O 3 exposure. Nevertheless, measurements of steady-state g s at midday may not account for altered stomatal responses to stressors. - In response to ozone exposure, stomata were slower in closing rather than in opening

  8. The relationship between some meteorological parameters and the tropospheric concentrations of ozone in the urban area of Belgrade

    Directory of Open Access Journals (Sweden)

    DRAGAN M. MARKOVIC

    2005-12-01

    Full Text Available During the period between June and December 2002, the concentrations of ozone in the air at 4 measuring sites in Belgrade were measured. The measuring periods varied from 10 days to several weeks. Themaximalmeasured daily concentrations of ozone ranged from 19 ppbv (23 December 2002 to 118 ppbv (23 June 2002. Ozone concentrations higher than, or equal to 90 ppbv were registered at threemeasuring sites. It was shown that at measuring sites characterized as urban, maximal O3 concentrations equal to, or higher than 90 ppbv occurred at high temperatures (higher than 30 oC and low wind speeds (mostly from the north. The measured ozone concentrations mostly showed characteristics usual for a daily photochemical ozone cycle, excluding the specificities influenced by the measuring site itself. Ozone transport was recorded at increased wind speeds, primarily from south-easterly directions. On the basis of he correlations between ozone concentration and the corresponding meteorological parameters, a validation of the measuring sites was performed from the aspect of their representativeness for the measurements.

  9. Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species

    International Nuclear Information System (INIS)

    Novak, K.; Schaub, M.; Fuhrer, J.; Skelly, J.M.; Hug, C.; Landolt, W.; Bleuler, P.; Kraeuchi, N.

    2005-01-01

    Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. - Reductions in leaf gas exchange corresponded to the onset of ozone-induced visible foliar injury for seedlings exposed to ambient ozone exposures

  10. Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species

    Energy Technology Data Exchange (ETDEWEB)

    Novak, K. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland)]. E-mail: kristopher.novak@wsl.ch; Schaub, M. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Fuhrer, J. [Swiss Federal Research Station for Agroecology and Agriculture FAL, 8046 Zurich (Switzerland); Skelly, J.M. [Department of Plant Pathology, The Pennsylvania State University, University Park, PA 16802 (United States); Hug, C. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Landolt, W. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Bleuler, P. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Kraeuchi, N. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland)

    2005-07-15

    Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. - Reductions in leaf gas exchange corresponded to the onset of ozone-induced visible foliar injury for seedlings exposed to ambient ozone exposures.

  11. Field responses of Prunus serotina and Asclepias syriaca to ozone around southern Lake Michigan.

    Science.gov (United States)

    Bennett, J P; Jepsen, E A; Roth, J A

    2006-07-01

    Higher ozone concentrations east of southern Lake Michigan compared to west of the lake were used to test hypotheses about injury and growth effects on two plant species. We measured approximately 1000 black cherry trees and over 3000 milkweed stems from 1999 to 2001 for this purpose. Black cherry branch elongation and milkweed growth and pod formation were significantly higher west of Lake Michigan while ozone injury was greater east of Lake Michigan. Using classification and regression tree (CART) analyses we determined that departures from normal precipitation, soil nitrogen and ozone exposure/peak hourly concentrations were the most important variables affecting cherry branch elongation, and milkweed stem height and pod formation. The effects of ozone were not consistently comparable with the effects of soil nutrients, weather, insect or disease injury, and depended on species. Ozone SUM06 exposures greater than 13 ppm-h decreased cherry branch elongation 18%; peak 1-h exposures greater than 93 ppb reduced milkweed stem height 13%; and peak 1-h concentrations greater than 98 ppb reduced pod formation 11% in milkweed.

  12. Ozone and its projection in regard to climate change

    Science.gov (United States)

    Melkonyan, Ani; Wagner, Patrick

    2013-03-01

    In this paper, the dependence of ozone-forming potential on temperature was analysed based on data from two stations (with an industrial and rural background, respectively) in North Rhine-Westphalia, Germany, for the period of 1983-2007. After examining the interrelations between ozone, NOx and temperature, a projection of the days with ozone exceedance (over a limit value of a daily maximum 8-h average ≥ 120 μg m-3 for 25 days per year averaged for 3 years) in terms of global climate change was made using probability theory and an autoregression integrated moving average (ARIMA) model. The results show that with a temperature increase of 3 K, the frequency of days when ozone exceeds its limit value will increase by 135% at the industrial station and by 87% at the rural background station.

  13. Association between outdoor ozone and compensated acute respiratory diseases among workers in Quebec (Canada).

    Science.gov (United States)

    Adam-Poupart, Ariane; Labrèche, France; Busque, Marc-Antoine; Brand, Allan; Duguay, Patrice; Fournier, Michel; Zayed, Joseph; Smargiassi, Audrey

    2015-01-01

    Respiratory effects of ozone in the workplace have not been extensively studied. Our aim was to explore the relationship between daily average ozone levels and compensated acute respiratory problems among workers in Quebec between 2003 and 2010 using a time-stratified case-crossover design. Health data came from the Workers' Compensation Board. Daily concentrations of ozone were estimated using a spatiotemporal model. Conditional logistic regressions, with and without adjustment for temperature, were used to estimate odds ratios (ORs, per 1 ppb increase of ozone), and lag effects were assessed. Relationships with respiratory compensations in all industrial sectors were essentially null. Positive non-statistically significant associations were observed for outdoor sectors, and decreased after controlling for temperature (ORs of 0.98; 1.01 and 1.05 at Lags 0, 1 and 2 respectively). Considering the predicted increase of air pollutant concentrations in the context of climate change, closer investigation should be carried out on outdoor workers.

  14. Ozone Induced Premature Mortality and Crop Yield Loss in China

    Science.gov (United States)

    Lin, Y.; Jiang, F.; Wang, H.

    2017-12-01

    Exposure to ambient ozone is a major risk factor for health impacts such as chronic obstructive pulmonary disease (COPD) and cause damage to plant and agricultural crops. But these impacts were usually evaluated separately in earlier studies. We apply Community Multi-scale Air Quality model to simulate the ambient O3 concentration at a resolution of 36 km×36 km across China. Then, we follow Global Burden of Diseases approach and AOT40 (i.e., above a threshold of 40 ppb) metric to estimate the premature mortalities and yield losses of major grain crops (i.e., winter wheat, rice and corn) across China due to surface ozone exposure, respectively. Our results show that ozone exposure leads to nearly 67,700 premature mortalities and 145 billion USD losses in 2014. The ozone induced yield losses of all crop production totaled 78 (49.9-112.6)million metric tons, worth 5.3 (3.4-7.6)billion USD, in China. The relative yield losses ranged from 8.5-14% for winter wheat, 3.9-15% for rice, and 2.2-5.5% for maize. We can see that the top four health affected provinces (Sichuan, Henan, Shandong, Jiangsu) are also ranking on the winter wheat and rice crop yield loss. Our results provide further evidence that surface ozone pollution is becoming urgent air pollution in China, and have important policy implications for China to alleviate the impacts of air pollution.

  15. Effects of age, socioeconomic status, and menstrual cycle on pulmonary response to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Seal, E. Jr.; McDonnell, W.F.; House, D.E. [Environmental Protection Agency, Research Triangle Park, NC (United States)

    1996-03-01

    The purpose of this study was to investigate the effects of age, socioeconomic status, and menstrual cycle phase on the pulmonary response to ozone exposure. Three hundred seventy-two healthy white and black young adults, between the ages of 18 and 35 y, were exposed only once to 0.0, 0.12, 0.18, 0.24, 0.30, or 0.40 ppm ozone for 2.3 h. Prior to and after exposure, pulmonary function tests were obtained. Prior to exposure, each subject completed a personal and family-history questionnaire. The response to this questionnaire were used to investigate age, socioeconomic status, and menstrual cycle phase effects on pulmonary responsiveness to ozone. We concluded that the ages of subjects, within the age range studied, had an effect on responsiveness (i.e., decrements in forced expiratory volume in 1 s decreased as the subjects` ages decreased). Socioeconomic status, as reflected by education of fathers, also appeared to affect forced expiratory volume in 1-s responsiveness to ozone, with the middle socioeconomic group being the most responsive. The phase of menstrual cycle did not have an impact on individual responsiveness to ozone. 14 refs., 4 figs.

  16. Inhibition of DNA replication by ozone in Chinese Hamster V79 cells

    International Nuclear Information System (INIS)

    Rasmussen, R.E.

    1986-01-01

    DNA replication in Chinese hamster lung fibroblasts, line V79, was depressed in a dose-dependent manner over an ozone concentration range of 1-10 ppm. When the cells were exposed for 1 h at concentrations up to 6 ppm, the rate of DNA replication, as measured by [ 3 H]thymidine incorporation, declined further during a 3-h period immediately following exposure. At higher ozone concentrations, at which more than 99.9% of the cells were killed, no further decline in DNA replication was seen beyond that immediately following exposure. Cultures exposed for 1 h to 10 mM ethyl methanesulfonate or to 10 J/m 2 of ultraviolet (UV) light showed a similar progressive decline in the rate of DNA replication. The inhibition of DNA replication by ozone resembled that seen after exposure of cells to chemical mutagens or radiation and did not resemble the inhibition produced by metabolic poisons. The results may indicate that ozone or its reaction products interact directly with DNA in a way that inhibits replication

  17. Effects of Low Ozone Concentrations and Short Exposure Times on the Mortality of Immature Stages of the Indian Meal Moth, Plodia Interpunctella (Lepidoptera: Pyralidae

    Directory of Open Access Journals (Sweden)

    Keivanloo Ensieh

    2014-07-01

    Full Text Available In Iran, the Indian meal moth, Plodia interpunctella (Hübner, is one of the most important pests of such stored products as date fruits and pistachio nuts. Ozone was applied as a gas at four concentrations (0, 2, 3, and 5 ppm for four different periods (30, 60, 90, and 120 min on the immature stages of P. interpunctella. The results indicated that by increasing the concentration and exposure time, the rate of mortality increased for all tested stages. This study showed that 12-day-old larvae were more susceptible than other stages when exposed to 5 ppm ozone for 120 min. The next in order of susceptibility were pupae, then 5-day-old larvae, and 17-dayold larvae had the highest sensitivity to ozonation. At the highest concentration of ozone, for the longest time, the least mortality rate was recorded for one-day-old eggs. According to the results, a reduction in the population density of P. interpunctella in laboratory experiments is promising. However, validation studies will be necessary to fully determine the potential of ozone as a replacement for the current post harvest chemical control of P. interpunctella on either pistachio nuts or date fruits.

  18. Ozone pollution affects flower numbers and timing in a simulated BAP priority calcareous grassland community

    International Nuclear Information System (INIS)

    Hayes, Felicity; Williamson, Jennifer; Mills, Gina

    2012-01-01

    Mesocosms representing the BAP Priority habitat ‘Calcareous Grassland’ were exposed to eight ozone profiles for twelve-weeks in two consecutive years. Half of the mesocosms received a reduced watering regime during the exposure periods. Numbers and timing of flowering in the second exposure period were related to ozone concentration and phytotoxic ozone dose (accumulated stomatal flux). For Lotus corniculatus, ozone accelerated the timing of the maximum number of flowers. An increase in mean ozone concentration from 30 ppb to 70 ppb corresponded with an advance in the timing of maximum flowering by six days. A significant reduction in flower numbers with increasing ozone was found for Campanula rotundifolia and Scabiosa columbaria and the relationship with ozone was stronger for those that were well-watered than for those with reduced watering. These changes in flowering timing and numbers could have large ecological impacts, affecting plant pollination and the food supply of nectar feeding insects. - Highlights: ► An increase in ozone accelerated timing of maximum flowering in Lotus corniculatus. ► Ozone reduced flower numbers in Campanula rotundifolia and Scabiosa columbaria. ► Reduced water availability did not protect most species from the effects of ozone. - Increased tropospheric ozone affected timing of flowering and maximum flower numbers in calcareous grassland mesocosms.

  19. 8 Hour Ozone Design Value for 1998-2000

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Ozone design value is based on the average of the annual 4th highest daily 8-hour maximum over a 3-year period (1998-2000) in this case. This is a human health...

  20. Long-Term Impairment of Sound Processing in the Auditory Midbrain by Daily Short-Term Exposure to Moderate Noise

    Directory of Open Access Journals (Sweden)

    Liang Cheng

    2017-01-01

    Full Text Available Most citizen people are exposed daily to environmental noise at moderate levels with a short duration. The aim of the present study was to determine the effects of daily short-term exposure to moderate noise on sound level processing in the auditory midbrain. Sound processing properties of auditory midbrain neurons were recorded in anesthetized mice exposed to moderate noise (80 dB SPL, 2 h/d for 6 weeks and were compared with those from age-matched controls. Neurons in exposed mice had a higher minimum threshold and maximum response intensity, a longer first spike latency, and a higher slope and narrower dynamic range for rate level function. However, these observed changes were greater in neurons with the best frequency within the noise exposure frequency range compared with those outside the frequency range. These sound processing properties also remained abnormal after a 12-week period of recovery in a quiet laboratory environment after completion of noise exposure. In conclusion, even daily short-term exposure to moderate noise can cause long-term impairment of sound level processing in a frequency-specific manner in auditory midbrain neurons.

  1. Effects of 0.12 and 0.80 PPM ozone on rat nasal and nasopharyngeal epithelial mucosubstances: Quantitative histochemistry

    International Nuclear Information System (INIS)

    Harkema, J.R.; Hotchkiss, J.A.; Henderson, R.F.

    1988-01-01

    The present study was designed to characterize changes in the quantity of mucosubstances in surface epithelia of rat nasal airways after short- term ozone exposure. Rats were exposed for 7 days (6 h/day) to 0.0, 0.12, or 0.8 ppm ozone, and killed immediately or 7 days after the last exposure. Nasal cavities were processed for morphometric analysis of intraepithelial mucosubstances. Compared to controls, rats exposed to 0.12 ppm ozone had increased amounts of stored mucosubstances within epithelium lining the medial aspect of the nasal turbinate immediately after exposure, but no change within epithelia of the nasopharynx. Rats exposed to 0.8 ppm ozone had increased quantities of stored mucosubstances within transitional and respiratory epithelium lining turbinates and lateral walls of the anterior nasal airway and significant decreases in stored mucosubstances within epithelia of the nasal septum at the end of exposure. Seven days after the end of exposure, the amounts of intraepithelial mucosubstances returned to control levels along the septum, but remained greater than those of controls along the turbinates. We demonstrated that exposures to ambient levels of ozone induce significant changes in the stored secretory product of nasal epithelium in the rat, and that these changes persist for at least 7 days post-exposure. (author)

  2. Assessment and Applications of NASA Ozone Data Products Derived from Aura OMI-MLS Satellite Measurements in Context of the GMI Chemical Transport Model

    Science.gov (United States)

    Ziemke, J. R.; Olsen, M. A.; Witte, J. C.; Douglass, A. R.; Strahan, S. E.; Wargan, K.; Liu, X.; Schoeberl, M. R.; Yang, K.; Kaplan, T. B.; hide

    2013-01-01

    Measurements from the Ozone Monitoring Instrument (OMI) and Microwave Limb Sounder (MLS), both onboard the Aura spacecraft, have been used to produce daily global maps of column and profile ozone since August 2004. Here we compare and evaluate three strategies to obtain daily maps of tropospheric and stratospheric ozone from OMI and MLS measurements: trajectory mapping, direct profile retrieval, and data assimilation. Evaluation is based upon an assessment that includes validation using ozonesondes and comparisons with the Global Modeling Initiative (GMI) chemical transport model (CTM). We investigate applications of the three ozone data products from near-decadal and inter-annual timescales to day-to-day case studies. Zonally averaged inter-annual changes in tropospheric ozone from all of the products in any latitude range are of the order 1-2 Dobson Units while changes (increases) over the 8-year Aura record investigated http://eospso.gsfc.nasa.gov/atbd-category/49 vary approximately 2-4 Dobson Units. It is demonstrated that all of the ozone products can measure and monitor exceptional tropospheric ozone events including major forest fire and pollution transport events. Stratospheric ozone during the Aura record has several anomalous inter-annual events including stratospheric warming split events in the Northern Hemisphere extra-tropics that are well captured using the data assimilation ozone profile product. Data assimilation with continuous daily global coverage and vertical ozone profile information is the best of the three strategies at generating a global tropospheric and stratospheric ozone product for science applications.

  3. Ozone Exposure-Response in Field Grown Soybean: Characterizing Intraspecific Variability of Physiology and Biochemistry

    Science.gov (United States)

    Crop losses due to rising tropospheric ozone concentrations ([ozone]) in 2000 were estimated to cost $1.8 to $3.9 billion in the U.S. and $3.0 to $5.5 billion in China, and are expected to grow with the predicted 25% increase in background [ozone] over the next 30 to 50 years. This challenge provide...

  4. Ozone flux over a Norway spruce forest and correlation with net ecosystem production

    International Nuclear Information System (INIS)

    Zapletal, Milos; Cudlin, Pavel; Chroust, Petr; Urban, Otmar; Pokorny, Radek; Edwards-Jonasova, Magda; Czerny, Radek; Janous, Dalibor; Taufarova, Klara; Vecera, Zbynek; Mikuska, Pavel; Paoletti, Elena

    2011-01-01

    Daily ozone deposition flux to a Norway spruce forest in Czech Republic was measured using the gradient method in July and August 2008. Results were in good agreement with a deposition flux model. The mean daily stomatal uptake of ozone was around 47% of total deposition. Average deposition velocity was 0.39 cm s -1 and 0.36 cm s -1 by the gradient method and the deposition model, respectively. Measured and modelled non-stomatal uptake was around 0.2 cm s -1 . In addition, net ecosystem production (NEP) was measured by using Eddy Covariance and correlations with O 3 concentrations at 15 m a.g.l., total deposition and stomatal uptake were tested. Total deposition and stomatal uptake of ozone significantly decreased NEP, especially by high intensities of solar radiation. - Highlights: → We estimate ozone deposition flux to a Norway spruce forest using the gradient method and model. → The mean stomatal uptake of ozone is approximately 47% of the total deposition. → We measure net ecosystem production (NEP) using Eddy Covariance. → We test whether elevated total deposition and stomatal uptake of O 3 imply a reduction of NEP. → Deposition and stomatal uptake of O 3 decrease NEP, especially by high intensities of solar radiation. - Net ecosystem production of a Norway spruce forest decreases with increasing deposition and stomatal uptake of ozone.

  5. Effects of ozone on crops in north-west Pakistan

    International Nuclear Information System (INIS)

    Ahmad, Muhammad Nauman; Büker, Patrick; Khalid, Sofia; Van Den Berg, Leon; Shah, Hamid Ullah; Wahid, Abdul; Emberson, Lisa; Power, Sally A.; Ashmore, Mike

    2013-01-01

    Although ozone is well-documented to reduce crop yields in the densely populated Indo-Gangetic Plain, there is little knowledge of its effects in other parts of south Asia. We surveyed crops close to the city of Peshawar, in north-west Pakistan, for visible injury, linking this to passive measurements of ozone concentrations. Foliar injury was found on potato, onion and cotton when mean monthly ozone concentrations exceeded 45 ppb. The symptoms on onion were reproduced in ozone fumigation experiments, which also showed that daytime ozone concentrations of 60 ppb significantly reduce the growth of a major Pakistani onion variety. Aphid infestation on spinach was also reduced at these elevated ozone concentrations. The ozone concentrations measured in April–May in Peshawar, and used in the fumigation experiment, are comparable to those that have been modelled to occur over many parts of south Asia, where ozone may be a significant threat to sensitive crops. -- Highlights: ► Visible ozone injury to onion, cotton and potato was identified in north-west Pakistan. ► The symptoms on onion were reproduced by exposure to elevated ozone. ► Elevated ozone levels also significantly reduced onion growth. ► Levels of aphid infestation on spinach were lower under elevated ozone. ► These effects were observed at ozone levels that have been modelled to occur widely across south Asia. -- Ozone concentrations in NW Pakistan have adverse effects on sensitive crop species

  6. Interaction between ozone and airborne particulate matter in office air

    DEFF Research Database (Denmark)

    Mølhave, Lars; Kjærgaard, Søren K.; Sigsgaard, Torben

    2005-01-01

    This study investigated the hypotheses that humans are affected by air pollution caused by ozone and house dust, that the effect of simultaneous exposure to ozone and dust in the air is larger than the effect of these two pollutants individually, and that the effects can be measured as release of...

  7. Factors affecting ozone removal rates in a simulated aircraft cabin environment

    DEFF Research Database (Denmark)

    Tamas, Gyöngyi; Weschler, Charles J.; Bako-Biro, Zsolt

    2006-01-01

    of people, soiled T-shirts, aircraft seats and a used HEPA filter, we have been able in the course of 24 experiments to isolate the contributions of these and other factors to the removal of ozone from the cabin air. In the case of this simulated aircraft, people were responsible for almost 60% of the ozone...... present, the measured ratio of ozone's concentration in the cabin versus that outside the cabin was 0.15-0.21, smaller than levels reported in the literature. The results reinforce the conclusion that the optimal way to reduce people's exposure to both ozone and ozone oxidation products is to efficiently...

  8. Associations between daily outpatient visits for respiratory diseases and ambient fine particulate matter and ozone levels in Shanghai, China.

    Science.gov (United States)

    Wang, Yiyi; Zu, Yaqun; Huang, Lin; Zhang, Hongliang; Wang, Changhui; Hu, Jianlin

    2018-09-01

    Air pollution in China has been very serious during the recent decades. However, few studies have investigated the effects of short-term exposure to PM 2.5 and O 3 on daily outpatient visits for respiratory diseases. We examined the effects of PM 2.5 and O 3 on the daily outpatient visits for respiratory diseases, explored the sensitivities of different population subgroups and analyzed the relative risk (RR) of PM 2.5 and O 3 in different seasons in Shanghai during 2013-2016. The generalized linear model (GLM) was applied to analyze the exposure-response relationship between air pollutants (daily average PM 2.5 and daily maximum 8-h average O 3 ), and daily outpatient visits due to respiratory diseases. The sensitivities of males and females at the ages of 15-60 yr-old and 60+ yr-old to the pollutants were also studied for the whole year and for the cold and warm months, respectively. Finally, the results of the single-day lagged model were compared with that of the moving average lag model. At lag 0 day, the RR of respiratory outpatients increased by 0.37% with a 10 μg/m 3 increase in PM 2.5 . Exposure to PM 2.5 (RR, 1.0047, 95% CI, 1.0032-1.0062) was more sensitive for females than for males (RR, 1.0025, 95% CI, 1.0008-1.0041), and was more sensitive for the 15-60 yr-old (RR, 1.0041, 95% CI, 1.0027-1.0055) than the 60+ yr-old age group (RR, 1.0031, 95% CI, 1.0014-1.0049). O 3 was not significantly associated with respiratory outpatient visits during the warm periods, but was negatively associated during the cold periods. PM 2.5 was more significantly in the cold periods than that in the warm periods. The results indicated that control of PM 2.5 , compared to O 3 , in the cold periods would be more beneficial to the respiratory health in Shanghai. In addition, the single-day lagged model underestimated the relationship between PM 2.5 and O 3 and outpatient visits for respiratory diseases compared to the moving average lag model. Copyright © 2018 Elsevier Ltd

  9. Ozone-Induced Nasal Type 2 Immunity in Mice Is Dependent on Innate Lymphoid Cells.

    Science.gov (United States)

    Kumagai, Kazuyoshi; Lewandowski, Ryan; Jackson-Humbles, Daven N; Li, Ning; Van Dyken, Steven J; Wagner, James G; Harkema, Jack R

    2016-06-01

    Epidemiological studies suggest that elevated ambient concentrations of ozone are associated with activation of eosinophils in the nasal airways of atopic and nonatopic children. Mice repeatedly exposed to ozone develop eosinophilic rhinitis and type 2 immune responses. In this study, we determined the role of innate lymphoid cells (ILCs) in the pathogenesis of ozone-induced eosinophilic rhinitis by using lymphoid-sufficient C57BL/6 mice, Rag2(-/-) mice that are devoid of T cells and B cells, and Rag2(-/-)Il2rg(-/-) mice that are depleted of all lymphoid cells including ILCs. The animals were exposed to 0 or 0.8 ppm ozone for 9 consecutive weekdays (4 h/d). Mice were killed 24 hours after exposure, and nasal tissues were selected for histopathology and gene expression analysis. ILC-sufficient C57BL/6 and Rag2(-/-) mice exposed to ozone developed marked eosinophilic rhinitis and epithelial remodeling (e.g., epithelial hyperplasia and mucous cell metaplasia). Chitinase-like proteins and alarmins (IL-33, IL-25, and thymic stromal lymphopoietin) were also increased morphometrically in the nasal epithelium of ozone-exposed C57BL/6 and Rag2(-/-) mice. Ozone exposure elicited increased expression of Il4, Il5, Il13, St2, eotaxin, MCP-2, Gob5, Arg1, Fizz1, and Ym2 mRNA in C57BL/6 and Rag2(-/-) mice. In contrast, ozone-exposed ILC-deficient Rag2(-/-)Il2rg(-/-) mice had no nasal lesions or overexpression of Th2- or ILC2-related transcripts. These results indicate that ozone-induced eosinophilic rhinitis, nasal epithelial remodeling, and type 2 immune activation are dependent on ILCs. To the best of our knowledge, this is the first study to demonstrate that ILCs play an important role in the nasal pathology induced by repeated ozone exposure.

  10. Distribution ozone concentration in Klang Valley using GIS approaches

    Science.gov (United States)

    Sulaiman, A.; Rahman, A. A. Ab; Maulud, K. N. Abdul; Latif, M. T.; Ahmad, F.; Wahid, M. A. Abdul; Ibrahim, M. A.; Halim, N. D. Abdul

    2017-05-01

    Today, ozone has become one of the main air pollutants in Malaysia. The high ozone precursor concentrations have been encouraging the ozone production. The development of the Klang Valley, Malaysia has many types of physical activities such as urban commercial, industrial area, settlement area and others, which has increased the risk of atmospheric pollution. The purpose of this paper is to determine the spatial distribution between types of land use and ozone concentration that are occurred in the year 2014. The study areas for this paper include Shah Alam, Kajang, Petaling Jaya and Port Klang. Distribution of ozone concentration will be showed via spatial analysis tools in Geographic Information Systems (GIS) approached and the types of land use will be extracted using Remote Sensing technique. The result showed 97 ppb (parts-per-billion, 10-9) and 161 ppb recorded at Port Klang and Shah Alam respectively that are mainly represented by the settlement area. Therefore, the physical land use need to be monitor and controlled by the government in order to make sure the ozone production for daily per hour will not exceed the regulation allowed.

  11. Distribution ozone concentration in Klang Valley using GIS approaches

    International Nuclear Information System (INIS)

    Sulaiman, A; Ab Rahman, A A; Abdul Maulud, K N; Abdul Wahid, M A; Ibrahim, M A; Latif, M T; Abdul Halim, N D; Ahmad, F

    2017-01-01

    Today, ozone has become one of the main air pollutants in Malaysia. The high ozone precursor concentrations have been encouraging the ozone production. The development of the Klang Valley, Malaysia has many types of physical activities such as urban commercial, industrial area, settlement area and others, which has increased the risk of atmospheric pollution. The purpose of this paper is to determine the spatial distribution between types of land use and ozone concentration that are occurred in the year 2014. The study areas for this paper include Shah Alam, Kajang, Petaling Jaya and Port Klang. Distribution of ozone concentration will be showed via spatial analysis tools in Geographic Information Systems (GIS) approached and the types of land use will be extracted using Remote Sensing technique. The result showed 97 ppb (parts-per-billion, 10 -9 ) and 161 ppb recorded at Port Klang and Shah Alam respectively that are mainly represented by the settlement area. Therefore, the physical land use need to be monitor and controlled by the government in order to make sure the ozone production for daily per hour will not exceed the regulation allowed. (paper)

  12. The biological effects of ozone on representative members of five groups of animal viruses

    Energy Technology Data Exchange (ETDEWEB)

    Bolton, D.C.; Zee, Y.C.; Osebold, J.W.

    1982-04-01

    In an effort to establish the biological relevance of the reactions of ozone with soluble proteins and lipid bilayer membrane systems, representative viruses from five major virus groups were exposed to moderate concentrations of ozone. The virus suspensions were exposed at 37/sup 0/C to 0.00, 0.16, and 0.64 ppm ozone in the gas phase. The ozone reacted with the virus suspensions as a thin film of fluid on the surface of a rotating culture bottle as the gas was drawn through the bottle at a flow rate of 2 liters/min. The three enveloped viruses tested exhibited different susceptibilities to ozone inactivation which correlated with their thermolability in the absence of ozone. The order of susceptibility to ozone inactivation of the enveloped viruses was vesicular stomatitis virus (VSV) (Rhabdoviridae) > influenza A virus (WSN strain) (Orthomyxoviridae) > infectious bovine rhinotracheitis virus (IBRV) (Herpesviridae). The inactivation reactions of the enveloped viruses with ozone showed pseudo-first-order kinetics. A simple reaction model was used to derive a reaction rate expression from which rate constrants and reaction stoichiometry were estimated. In contrast to the enveloped viruses, the two nonenveloped viruses examined were relatively resistant to ozone inactivation. Polio virus type I (Picornaviridae) was found to be completely resistant to ozone inactivation after 60 hr exposure to either ozone concentration, while infectious canine hepatitis virus (Adenoviridae) showed only slight inactivation after exposure to 0.64 ppm ozone for 66 hr. The significance of these results with regard to the reactions of ozone with cell membranes and other components is discussed.

  13. Effects of Botrytis and ozone on bracts and flowers of poinsettia cultivars

    Energy Technology Data Exchange (ETDEWEB)

    Manning, W.J.; Feder, W.A.; Perkins, I.

    1972-09-01

    Variability, ranging from complete resistance to extensive susceptibility, was observed when flowers and bracts of 14 cultivars of poinsettia were inoculated with spores of Botrytis cinerea. Flowers and bracts were not visibly injured by exposure to ozone levels up to 45 pphm. Ozone did not have significant fungicidal effects, as measured by visual disease incidence following incubation, when inoculated flowers and bracts were exposed to ozone at 15, 25, 35, and 45 pphm ozone for 4 hr prior to incubation. 8 references, 1 table.

  14. Ozone-induced changes in the pulmonary clearance of (99m)Tc-DTPA in man

    International Nuclear Information System (INIS)

    Kehrl, H.R.; Vincent, L.M.; Kowalsky, R.J.; Horstman, D.H.; O'Neil, J.J.

    1988-05-01

    Ozone is a respiratory irritant that has been shown in animals to increase the premeability of the respiratory epithelium. In the study the authors have recently reported that respiratory epithelial permeability was similarly affected in eight healthy non-smoking young men exposed to ozone (ARRD, 135 (1987) 1124-8). Permeability was evaluated by determining the pulmonary clearance of inhaled aerosolized 99mTc-DTPA with sequential posterior lung imaging by a computer-assisted gamma camera. In a randomized crossover design, 16 young men were exposed for 2 h to purified air and 0.4 ppm ozone while performing intermittent high intensity treadmill exercise; forced vital capacity (FVC) was measured before and at the end of exposures. The results demonstrate that ozone exposure increased respiratory epithelial permeability. Such an increase may be a manifestation of direct ozone-induced epithelial-cell injury, lung inflammation, or both

  15. Comparison of seasonal variations of ozone exposure and fluxes in a Mediterranean Holm oak forest between the exceptionally dry 2003 and the following year

    International Nuclear Information System (INIS)

    Gerosa, Giacomo; Finco, Angelo; Mereu, Simone; Vitale, Marcello; Manes, Fausto; Denti, Antonio Ballarin

    2009-01-01

    Ozone and energy fluxes have been measured using the eddy covariance technique, from June to December 2004 in Castelporziano near Rome (Italy), and compared to similar measurements made in the previous year. The studied ecosystem consisted in a typical Mediterranean Holm oak forest. Stomatal fluxes have been calculated using the resistance analogy and by inverting the Penmann-Monteith equation. Results showed that the average stomatal contribution accounts for 42.6% of the total fluxes. Non-stomatal deposition proved to be enhanced by increasing leaf wetness and air humidity during the autumnal months. From a comparison of the two years, it can be inferred that water supply is the most important limiting factor for ozone uptake and that prolonged droughts alter significantly the stomatal conductance, even 2 months after the soil water content is replenished. Ozone exposure, expressed as AOT40, behaves similarly to the cumulated stomatal flux in dry conditions whereas a different behaviour for the two indices appears in wet autumnal conditions. A difference also occurs between the two years. - Ozone fluxes to a Holm oak coastal forest show inter-annual variations depending on meteorological conditions and water availability.

  16. Innate Lymphoid Cells Mediate Pulmonary Eosinophilic Inflammation, Airway Mucous Cell Metaplasia, and Type 2 Immunity in Mice Exposed to Ozone.

    Science.gov (United States)

    Kumagai, Kazuyoshi; Lewandowski, Ryan P; Jackson-Humbles, Daven N; Buglak, Nicholas; Li, Ning; White, Kaylin; Van Dyken, Steven J; Wagner, James G; Harkema, Jack R

    2017-08-01

    Exposure to elevated levels of ambient ozone in photochemical smog is associated with eosinophilic airway inflammation and nonatopic asthma in children. In the present study, we determined the role of innate lymphoid cells (ILCs) in the pathogenesis of ozone-induced nonatopic asthma by using lymphoid cell-sufficient C57BL/6 mice, ILC-sufficient Rag2 -/- mice (devoid of T and B cells), and ILC-deficient Rag2 -/- Il2rg -/- mice (depleted of all lymphoid cells including ILCs). Mice were exposed to 0 or 0.8 parts per million ozone for 1 day or 9 consecutive weekdays (4 hr/day). A single exposure to ozone caused neutrophilic inflammation, airway epithelial injury, and reparative DNA synthesis in all strains of mice, irrespective of the presence or absence of ILCs. In contrast, 9-day exposures induced eosinophilic inflammation and mucous cell metaplasia only in the lungs of ILC-sufficient mice. Repeated ozone exposures also elicited increased messenger RNA expression of transcripts associated with type 2 immunity and airway mucus production in ILC-sufficient mice. ILC-deficient mice repeatedly exposed to ozone had no pulmonary pathology or increased gene expression related to type 2 immunity. These results suggest a new paradigm for the biologic mechanisms underlying the development of a phenotype of childhood nonatopic asthma that has been linked to ambient ozone exposures.

  17. Forecasting ozone concentrations in the east of Croatia using ...

    Indian Academy of Sciences (India)

    for urban and another one for rural area in the eastern part of Croatia. ... 2010). Apart from the negative impact on respiratory system, atmo- ..... Figure 3. Daily average ozone concentrations in the rural (Tikveš) and urban (Osijek) areas.

  18. Associations between ozone and morbidity using the Spatial Synoptic Classification system

    Directory of Open Access Journals (Sweden)

    Arora Gurmeet

    2011-05-01

    Full Text Available Abstract Background Synoptic circulation patterns (large-scale tropospheric motion systems affect air pollution and, potentially, air-pollution-morbidity associations. We evaluated the effect of synoptic circulation patterns (air masses on the association between ozone and hospital admissions for asthma and myocardial infarction (MI among adults in North Carolina. Methods Daily surface meteorology data (including precipitation, wind speed, and dew point for five selected cities in North Carolina were obtained from the U.S. EPA Air Quality System (AQS, which were in turn based on data from the National Climatic Data Center of the National Oceanic and Atmospheric Administration. We used the Spatial Synoptic Classification system to classify each day of the 9-year period from 1996 through 2004 into one of seven different air mass types: dry polar, dry moderate, dry tropical, moist polar, moist moderate, moist tropical, or transitional. Daily 24-hour maximum 1-hour ambient concentrations of ozone were obtained from the AQS. Asthma and MI hospital admissions data for the 9-year period were obtained from the North Carolina Department of Health and Human Services. Generalized linear models were used to assess the association of the hospitalizations with ozone concentrations and specific air mass types, using pollutant lags of 0 to 5 days. We examined the effect across cities on days with the same air mass type. In all models we adjusted for dew point and day-of-the-week effects related to hospital admissions. Results Ozone was associated with asthma under dry tropical (1- to 5-day lags, transitional (3- and 4-day lags, and extreme moist tropical (0-day lag air masses. Ozone was associated with MI only under the extreme moist tropical (5-day lag air masses. Conclusions Elevated ozone levels are associated with dry tropical, dry moderate, and moist tropical air masses, with the highest ozone levels being associated with the dry tropical air mass. Certain

  19. Mexico City ozone concentrations as a function of readily-available meteorological parameters

    International Nuclear Information System (INIS)

    Brown, M.J.

    1994-01-01

    Daily maximum ozone concentrations measured at four sites within the Mexico City basin during the winter months are plotted as functions of different meteorological parameters that are routinely measured at surface stations. We found that ozone concentrations are most strongly correlated to the increase in daytime temperature and the maximum daytime wind speed. We also discovered that high ozone values at the sites in the southern end of the basin occur when winds come out of the northeast. In contrast, wind direction was found to be uncorrelated with high ozone values at the northern sites. From straightforward combinations of the meteorological variables, we derived some simple rules for estimating lower and upper bounds on the ozone concentration. Scatter in the data was too long to give significance to best-fit equations and statistics. Additionally, a small rawinsonde data set was used to investigate ozone's dependence on boundary-layer height and near-surface temperature gradient. Results were inconclusive, however, due to the small size of the data set

  20. Inhaled ozone (O3)-induces changes in serum metabolomic and liver transcriptomic profiles in rats

    International Nuclear Information System (INIS)

    Miller, Desinia B.; Karoly, Edward D.; Jones, Jan C.; Ward, William O.; Vallanat, Beena D.; Andrews, Debora L.; Schladweiler, Mette C.; Snow, Samantha J.; Bass, Virginia L.; Richards, Judy E.; Ghio, Andrew J.; Cascio, Wayne E.; Ledbetter, Allen D.; Kodavanti, Urmila P.

    2015-01-01

    Air pollution has been linked to increased incidence of diabetes. Recently, we showed that ozone (O 3 ) induces glucose intolerance, and increases serum leptin and epinephrine in Brown Norway rats. In this study, we hypothesized that O 3 exposure will cause systemic changes in metabolic homeostasis and that serum metabolomic and liver transcriptomic profiling will provide mechanistic insights. In the first experiment, male Wistar Kyoto (WKY) rats were exposed to filtered air (FA) or O 3 at 0.25, 0.50, or 1.0 ppm, 6 h/day for two days to establish concentration-related effects on glucose tolerance and lung injury. In a second experiment, rats were exposed to FA or 1.0 ppm O 3 , 6 h/day for either one or two consecutive days, and systemic metabolic responses were determined immediately after or 18 h post-exposure. O 3 increased serum glucose and leptin on day 1. Glucose intolerance persisted through two days of exposure but reversed 18 h-post second exposure. O 3 increased circulating metabolites of glycolysis, long-chain free fatty acids, branched-chain amino acids and cholesterol, while 1,5-anhydroglucitol, bile acids and metabolites of TCA cycle were decreased, indicating impaired glycemic control, proteolysis and lipolysis. Liver gene expression increased for markers of glycolysis, TCA cycle and gluconeogenesis, and decreased for markers of steroid and fat biosynthesis. Genes involved in apoptosis and mitochondrial function were also impacted by O 3 . In conclusion, short-term O 3 exposure induces global metabolic derangement involving glucose, lipid, and amino acid metabolism, typical of a stress–response. It remains to be examined if these alterations contribute to insulin resistance upon chronic exposure. - Highlights: • Ozone, an ubiquitous air pollutant induces acute systemic metabolic derangement. • Serum metabolomic approach provides novel insights in ozone-induced changes. • Ozone exposure induces leptinemia, hyperglycemia, and glucose intolerance

  1. Exposure to Non-Extreme Solar UV Daylight: Spectral Characterization, Effects on Skin and Photoprotection

    Directory of Open Access Journals (Sweden)

    Claire Marionnet

    2014-12-01

    Full Text Available The link between chronic sun exposure of human skin and harmful clinical consequences such as photo-aging and skin cancers is now indisputable. These effects are mostly due to ultraviolet (UV rays (UVA, 320–400 nm and UVB, 280–320 nm. The UVA/UVB ratio can vary with latitude, season, hour, meteorology and ozone layer, leading to different exposure conditions. Zenithal sun exposure (for example on a beach around noon under a clear sky can rapidly induce visible and well-characterized clinical consequences such as sunburn, predominantly induced by UVB. However, a limited part of the global population is exposed daily to such intense irradiance and until recently little attention has been paid to solar exposure that does not induce any short term clinical impact. This paper will review different studies on non-extreme daily UV exposures with: (1 the characterization and the definition of the standard UV daylight and its simulation in the laboratory; (2 description of the biological and clinical effects of such UV exposure in an in vitro reconstructed human skin model and in human skin in vivo, emphasizing the contribution of UVA rays and (3 analysis of photoprotection approaches dedicated to prevent the harmful impact of such UV exposure.

  2. Exposure to non-extreme solar UV daylight: spectral characterization, effects on skin and photoprotection.

    Science.gov (United States)

    Marionnet, Claire; Tricaud, Caroline; Bernerd, Françoise

    2014-12-23

    The link between chronic sun exposure of human skin and harmful clinical consequences such as photo-aging and skin cancers is now indisputable. These effects are mostly due to ultraviolet (UV) rays (UVA, 320-400 nm and UVB, 280-320 nm). The UVA/UVB ratio can vary with latitude, season, hour, meteorology and ozone layer, leading to different exposure conditions. Zenithal sun exposure (for example on a beach around noon under a clear sky) can rapidly induce visible and well-characterized clinical consequences such as sunburn, predominantly induced by UVB. However, a limited part of the global population is exposed daily to such intense irradiance and until recently little attention has been paid to solar exposure that does not induce any short term clinical impact. This paper will review different studies on non-extreme daily UV exposures with: (1) the characterization and the definition of the standard UV daylight and its simulation in the laboratory; (2) description of the biological and clinical effects of such UV exposure in an in vitro reconstructed human skin model and in human skin in vivo, emphasizing the contribution of UVA rays and (3) analysis of photoprotection approaches dedicated to prevent the harmful impact of such UV exposure.

  3. Spatial distribution of ozone over Indonesia (Study case: Forest fire event 2015)

    Science.gov (United States)

    Muslimah, Sri; Buce Saleh, Muhamad; Hidayat, Rahmat

    2018-05-01

    Tropospheric ozone is known as surface ozone and caused several health impact. The objective of this study was to analysis spatial distribution of tropospheric ozone over Indonesia case study forest fire event in 2015. Monthly observation measured by Ozone Monitoring Instrument (OMI) have been analysed from January – December 2015 to study spatial distribution of tropospheric ozone related to forest fire event 2015. The study discovered high level of tropospheric column ozone (TCO) from October to November 2015. The result shows increasing average of TCO from September to October almost 6 DU. Meanwhile, monthly number of hotspot is higher in September 2015 with total number 257 hotspot which is acquired by Moderate Resolution Imaging Spectrometer (MODIS) Terra version 6.1 with confidence level same or more than 90%. The hotspot distribution compared with spatial TCO distribution and shows interesting time lag with respect to hotspot distribution, one month. Further study for daily comparison of TCO and forest fire event needed. This result suggested that the tropospheric ozone over the Indonesian region increases in 2015 were remarkable and corresponded to forest fire event.

  4. Ozone exposure affects leaf wettability and tree water balance

    NARCIS (Netherlands)

    Schreuder, M.D.J.; Hove, van L.W.A.; Brewer, C.A.

    2001-01-01

    Relatively little is known about the influences of growing-season background ozone (O3) concentrations on leaf cuticles and foliar water loss. Using fumigation chambers, leaf wettability and foliar water loss were studied in two poplar species, Populus nigra and P. euramericana, and a conifer,

  5. Southern Hemisphere Additional Ozonesondes (SHADOZ) Ozone Climatology (2005-2009): Tropospheric and Tropical Tropopause Layer (TTL) Profiles with Comparisons to Omi-based Ozone Products

    Science.gov (United States)

    Thompson, Anne M.; Miller, Sonya K.; Tilmes, Simone; Kollonige, Debra W.; Witte, Jacquelyn C.; Oltmans, Samuel J.; Johnson, Brian J.; Fujiwara, Masatomo; Schmidlin, F. J.; Coetzee, G. J. R.; hide

    2012-01-01

    We present a regional and seasonal climatology of SHADOZ ozone profiles in the troposphere and tropical tropopause layer (TTL) based on measurements taken during the first five years of Aura, 2005-2009, when new stations joined the network at Hanoi, Vietnam; Hilo, Hawaii; Alajuela Heredia, Costa Rica; Cotonou, Benin. In all, 15 stations operated during that period. A west-to-east progression of decreasing convective influence and increasing pollution leads to distinct tropospheric ozone profiles in three regions: (1) western Pacific eastern Indian Ocean; (2) equatorial Americas (San Cristobal, Alajuela, Paramaribo); (3) Atlantic and Africa. Comparisons in total ozone column from soundings, the Ozone Monitoring Instrument (OMI, on Aura, 2004-) satellite and ground-based instrumentation are presented. Most stations show better agreement with OMI than they did for EPTOMS comparisons (1998-2004; Earth-ProbeTotal Ozone Mapping Spectrometer), partly due to a revised above-burst ozone climatology. Possible station biases in the stratospheric segment of the ozone measurement noted in the first 7 years of SHADOZ ozone profiles are re-examined. High stratospheric bias observed during the TOMS period appears to persist at one station. Comparisons of SHADOZ tropospheric ozone and the daily Trajectory-enhanced Tropospheric Ozone Residual (TTOR) product (based on OMIMLS) show that the satellite-derived column amount averages 25 low. Correlations between TTOR and the SHADOZ sondes are quite good (typical r2 0.5-0.8), however, which may account for why some published residual-based OMI products capture tropospheric interannual variability fairly realistically. On the other hand, no clear explanations emerge for why TTOR-sonde discrepancies vary over a wide range at most SHADOZ sites.

  6. Impact of increasing heat waves on U.S. ozone episodes in the 2050s: Results from a multimodel analysis using extreme value theory

    Science.gov (United States)

    Shen, L.; Mickley, L. J.; Gilleland, E.

    2016-04-01

    We develop a statistical model using extreme value theory to estimate the 2000-2050 changes in ozone episodes across the United States. We model the relationships between daily maximum temperature (Tmax) and maximum daily 8 h average (MDA8) ozone in May-September over 2003-2012 using a Point Process (PP) model. At ~20% of the sites, a marked decrease in the ozone-temperature slope occurs at high temperatures, defined as ozone suppression. The PP model sometimes fails to capture ozone-Tmax relationships, so we refit the ozone-Tmax slope using logistic regression and a generalized Pareto distribution model. We then apply the resulting hybrid-extreme value theory model to projections of Tmax from an ensemble of downscaled climate models. Assuming constant anthropogenic emissions at the present level, we find an average increase of 2.3 d a-1 in ozone episodes (>75 ppbv) across the United States by the 2050s, with a change of +3-9 d a-1 at many sites.

  7. Oxidation kinetics of hazelnut oil treated with ozone

    Directory of Open Access Journals (Sweden)

    H. Uzun

    2018-01-01

    Full Text Available The present study investigates the oxidation kinetics of hazelnut oil ozonated in different treatment periods (1, 5, 60 and 180 min. The kinetic rate constant (k was taken as the inverse of oxidation onset time (To observing a linear relationship from the plot of lnTo to isothermal temperatures (373, 383, 393, and 403 K carried out at differential scanning calorimetry. Kinetic parameters, activation energy (Ea, activation enthalpy (ΔH‡ and entropy (ΔS‡ were calculated based on the Arrhenius equation and activated complex theory. k values showed an exponential rise with the increase of ozone treatment time. The increase in k correlated well with the increase in the peroxide and free fatty acid values of all samples. Ea and ∆H‡ of the ozone treated oils showed a reducing trend and reflected an increased oxidation sensitivity after ozone treatment. Consistently, an increase in ∆S‡ indicated a faster oxidation reaction with an increase in ozone exposure time. However, no significant difference was observed in k, Ea, ΔH‡, ΔS‡ (p < 0.05 as a function of storage period, after the hazelnut oil was treated with ozone for 1 min.

  8. Oxidation kinetics of hazelnut oil treated with ozone

    International Nuclear Information System (INIS)

    Uzun, H.; Ibanoglu, E.

    2017-01-01

    The present study investigates the oxidation kinetics of hazelnut oil ozonated in different treatment periods (1, 5, 60 and 180 min). The kinetic rate constant (k) was taken as the inverse of oxidation onset time (To) observing a linear relationship from the plot of ln To to isothermal temperatures (373, 383, 393, and 403 K) carried out at differential scanning calorimetry. Kinetic parameters, activation energy (Ea), activation enthalpy (ΔH‡) and entropy (ΔS‡) were calculated based on the Arrhenius equation and activated complex theory. k values showed an exponential rise with the increase of ozone treatment time. The increase in k correlated well with the increase in the peroxide and free fatty acid values of all samples. Ea and ΔH‡ of the ozone treated oils showed a reducing trend and reflected an increased oxidation sensitivity after ozone treatment. Consistently, an increase in ΔS‡ indicated a faster oxidation reaction with an increase in ozone exposure time. However, no significant difference was observed in k, Ea, ΔH‡, ΔS‡ (p < 0.05) as a function of storage period, after the hazelnut oil was treated with ozone for 1 min. [es

  9. Assimilation of carbon and transport of assimilates in coniferous trees under the influence of airborne pollutants. Photosynthesis rate and assimilate distribution in young fir trees (Picea abies [L.]Karst.) under controlled exposure to ozone. Final report; Assimilation von Kohlenstoff und der Assimilattransport in Coniferen unter dem Einfluss von Luftschadstoffen. Photosyntheseleistung und Assimilatverteilung in jungen Fichten (Picea abies [L.]Karst.) unter kontrollierter Ozon-Exposition. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Willenbrink, J.; Schatten, T.

    1992-12-31

    In this project, effects of long-term, low-level ozone exposure on CO{sub 2}fixation and assimilate partitioning in 4-years spruces old were studied. 1. In October, ozone exposure resulted in a 40% decrease of photosynthesis. Chlorophyll content was not altered. Depression of net photosynthesis by ozone exposure fluctuates. At least partly, this depression of net photosynthesis might reflect an increase of respiration. After 6 weeks of ozone exposure, both stomatal conductivity and transpiration seemed to be lowered. However, internal [CO{sub 2}] and water use efficiency were not significantly altered. 2. Compared with the control, needles of ozone-exposed plants exhibited a shift of the {sup 14}C-ratio of {beta}-carotene/xanthophylls which effect faded away with the season (October). 3. In August and October, translocation of {sup 14}C-assimilates from the {sup 14}C-fed source leaves seems to be impeded by ozone exposure. 4. No O{sub 3}-related differences were found for the lipophilic as well as for the fractions of organic or amino acids. For the sink tissues (twig, stem, root), less label was found in non-starch residue in August (main growth season), in O{sub 3}-exposed plants. 5. Starch and sugar content of cortex, cambium, xylem, and of the root follow annual cycles. Under ozon exposure, levels of {sup 14}C-starch and {sup 14}C-sucrose are lowered whereas in the needles, build-up of {sup 14}C-starch was detected. 6. Obviously, long-term low-level ozone affects allocation of assimilates. Secondary effects on chloroplasts by the treatment cannot be excluded. (orig./UWA) [Deutsch] Unter Labor- bzw. Gewaechshausbedingungen wurde der Einfluss einer kontrollierten Ozonexposition auf die Photosyntheseleistung und die Assimilatverteilung in 4-jaehrigen Fichten untersucht. 1. Unter Ozon-Exposition wird die Netto-Photosyntheserate in den jungen Nadeln zum Herbst hin reduziert, waehrend der Chlorophyllgehalt unbeeinflusst bleibt. Die Photosyntheserate der jungen Nadeln

  10. Improve observation-based ground-level ozone spatial distribution by compositing satellite and surface observations: A simulation experiment

    Science.gov (United States)

    Zhang, Yuzhong; Wang, Yuhang; Crawford, James; Cheng, Ye; Li, Jianfeng

    2018-05-01

    Obtaining the full spatial coverage of daily surface ozone fields is challenging because of the sparsity of the surface monitoring network and the difficulty in direct satellite retrievals of surface ozone. We propose an indirect satellite retrieval framework to utilize the information from satellite-measured column densities of tropospheric NO2 and CH2O, which are sensitive to the lower troposphere, to derive surface ozone fields. The method is applicable to upcoming geostationary satellites with high-quality NO2 and CH2O measurements. To prove the concept, we conduct a simulation experiment using a 3-D chemical transport model for July 2011 over the eastern US. The results show that a second order regression using both NO2 and CH2O column densities can be an effective predictor for daily maximum 8-h average ozone. Furthermore, this indirect retrieval approach is shown to be complementary to spatial interpolation of surface observations, especially in regions where the surface sites are sparse. Combining column observations of NO2 and CH2O with surface site measurements leads to an improved representation of surface ozone over simple kriging, increasing the R2 value from 0.53 to 0.64 at a surface site distance of 252 km. The improvements are even more significant with larger surface site distances. The simulation experiment suggests that the indirect satellite retrieval technique can potentially be a useful tool to derive the full spatial coverage of daily surface ozone fields if satellite observation uncertainty is moderate.

  11. Modeling ozone bioindicator injury with microscale and landscape-scale explanatory variables: A logistic regression approach

    Science.gov (United States)

    John W. Coulston

    2011-01-01

    Tropospheric ozone occurs at phytotoxic levels in the United States (Lefohn and Pinkerton 1988). Several plant species, including commercially important timber species, are sensitive to elevated ozone levels. Exposure to elevated ozone can cause growth reduction and foliar injury and make trees more susceptible to secondary stressors such as insects and pathogens (...

  12. Depletion of the ozone layer: consequences for non-infectious human diseases

    International Nuclear Information System (INIS)

    Bentham, G.

    1993-01-01

    Stratospheric ozone depletion threatens to increase exposure to ultraviolet (UV) radiation which is known to be a factor in a number of diseases. There is little doubt that cumulative exposure to UV radiation is important in the aetiology of non-melanoma skin cancers. Evidence is also strong for a link with cutaneous malignant melanoma, although here it appears to be intermittent intense exposure that is most damaging. More controversial is the view that exposure to solar radiation is a significant factor in ocular damage, particularly in the formation of cataracts. Earlier studies pointing to such an effect have been criticized and alternative aetiological hypotheses have been proposed. However, other studies do show an effect of UV exposure on cortical cataract. Concern is also growing that UV may be capable of activating viruses and have immunological effects that might exacerbate infectious disease. Very worrying is the possibility that UV exposure can activate the human immunodeficiency virus which might accelerate the onset AIDS. Any such health effects that have been observed in human populations are the result of exposure to existing, naturally occurring levels of UV radiation. There is, therefore, great concern about the possible exacerbation of these impacts as a result of increased exposure to UV radiation associated with stratospheric ozone depletion. However, any assessment of the nature and scale of such impacts on human health has to deal with several major problems and these are the focus of this paper. There are uncertainties about recent trends in stratospheric ozone and problems in the prediction of future changes

  13. Intrapulmonary reactions of workers exposed to dust and ozone

    Energy Technology Data Exchange (ETDEWEB)

    Tsunoda, T; Nakadate, T; Sakurai, M; Sakurai, Y

    1984-01-01

    Forty-one dust-and-ozone-exposed and 37 nonexposed workers, belonging to the Research and Development Division of a photo-copier manufacturing industry, were examined to assess the effect of the exposure to carbon, iron and resin dust and ozone in the air of the work environment by means of questionnaires on their physical condition, smoking habits and exposure history by interview, chest X-rays, testing of ventilatory functions, transcutaneous PO2 (tcPO2) test and H2O2-induced hemolysis test. The following results were obtained. Respirable dust concentrations in the air of the work place were 0.1-1.0 mg/m3, total dust concentrations 0.2-2.0 mg/m3, and ozone concentrations 0.004-0.06 ppm (0.008-0.12 mg/m3). According to the Japanese Classification of Radiographs of Pneumoconioses, the exposed workers showed a higher rate of profusion 0/1 and over, and category 1 and over (1/0 and over) than the nonexposed workers. Ventilatory function testing revealed no difference between exposed workers and nonexposed workers, but small airway narrowing was suspected in smoking workers in comparison with nonsmoking workers. Transcutaneous PO2 showed no difference between exposed and nonexposed workers, between smoking and nonsmoking workers, and between any of the paired six combinations out of the four groups of workers, i.e., nonsmoking and nonexposed, nonsmoking and exposed, smoking and nonexposed, and smoking and exposed. It was estimated by H2O2-induced hemolysis test that smoking and/or dust exposure, especially long-term exposure, gave rise to aggravation of fragility of the erythrocyte membrane by lipid peroxidation with ozone or active oxygen produced by the reaction of dust and alveolar macrophages.

  14. Products of Ozone-initiated Chemistry during 4-hour Exposures of Human Subjects in a Simulated Aircraft Cabin

    DEFF Research Database (Denmark)

    Weschler, Charles J.; Wisthaler, Armin; Tamás, Gyöngyi

    2006-01-01

    Proton-transfer-reaction mass spectrometry (PTR-MS) was used to examine organic compounds in the air of a simulated aircraft cabin under four conditions: low ozone, low air exchange rate; low ozone, high air exchange rate; high ozone, low air exchange rate; high ozone, high air exchange rate....... The results showed large differences in the chemical composition of the cabin air between the low and high ozone conditions. These differences were more pronounced at the low air exchange condition....

  15. Global impacts of surface ozone changes on crop yields and land use

    NARCIS (Netherlands)

    Chuwah, C.D.; Noije, van Twan; Vuuren, van Detlef P.; Stehfest, Elke; Hazeleger, Wilco

    2015-01-01

    Exposure to surface ozone has detrimental impacts on vegetation and crop yields. In this study, we estimate ozone impacts on crop production and subsequent impacts on land use in the 2005-2050 period using results of the TM5 atmospheric chemistry and IMAGE integrated assessment model. For the

  16. Global impacts of surface ozone changes on crop yields and land use

    NARCIS (Netherlands)

    Chuwah, Clifford; van Noije, Twan; van Vuuren, Detlef P.; Stehfest, Elke; Hazeleger, Wilco

    2015-01-01

    Exposure to surface ozone has detrimental impacts on vegetation and crop yields. In this study, we estimate ozone impacts on crop production and subsequent impacts on land use in the 2005-2050 period using results of the TM5 atmospheric chemistry and IMAGE integrated assessment model. For the crops

  17. Aviation-attributable ozone as a driver for changes in mortality related to air quality and skin cancer

    Science.gov (United States)

    Eastham, Sebastian D.; Barrett, Steven R. H.

    2016-11-01

    Aviation is a significant source of tropospheric ozone, which is a critical UV blocking agent, an indirect precursor to the formation of particulate matter, and a respiratory health hazard. To date, investigations of human health impacts related to aviation emissions have focused on particulate matter, and no global estimate yet exists of the combined health impact of aviation due to ozone, particulate matter and UV exposure changes. We use a coupled tropospheric-stratospheric chemical-transport model with a global aviation emissions inventory to estimate the total impact of aviation on all three risk factors. We find that surface ozone due to aviation emissions is maximized during hemispheric winter due to the greater wintertime chemical lifetime of ozone, but that a smaller enhancement of 0.5 ppbv occurs during summertime. This summertime increase results in an estimated 6,800 premature mortalities per year due to ozone exposure, over three times greater than previous estimates. During the winter maximum, interaction with high background NOx concentrations results in enhanced production of nitrate aerosol and increased annual average exposure to particulate matter. This ozone perturbation is shown to be the driving mechanism behind an additional 9,200 premature mortalities due to exposure to particulate matter. However, the increase in tropospheric ozone is also found to result in 400 fewer mortalities due to melanoma skin cancer in 2006. This is the first estimate of global melanoma mortality due to aviation, and the first estimate of skin cancer mortality impacts due to aviation using a global chemical transport model.

  18. Ozone treatment of shell eggs to preserve functional quality and enhance shelf life during storage.

    Science.gov (United States)

    Yüceer, Muhammed; Aday, Mehmet Seçkin; Caner, Cengiz

    2016-06-01

    Eggs have long been recognised as a source of high-quality proteins. Many methods exist to extend shelf life of food and one of them is ozone treatment, which is an emerging technology for disinfecting surfaces in the food industry. This study aimed to extend the shelf life of fresh eggs using gaseous ozone treatments at concentrations of 2, 4 and 6 ppm with exposure times of 2 and 5 min during storage for 6 weeks at 24 °C. The effect of the treatments on interior quality and functional properties of eggs is also reported. Ozone concentration and exposure time significantly affected the Haugh unit (HU), yolk index, albumen pH, relative whipping capacity (RWC), and albumen viscosity of eggs during the storage. Control eggs had the highest albumen pH and lowest albumen viscosity. Attributes such as albumen pH and RWC of eggs exposed to ozone treatments were better than the control samples. The measurement results showed that ozone concentration at 6 ppm and exposure time of 5 min can be applied to fresh eggs and extend shelf life up to 6 weeks at 24 °C storage period. Ozone treatments helped to maintain egg quality for a longer time. Ozone concentrations at 2 and 4 ppm showed promising results in maintaining internal quality and functional properties of fresh eggs during storage. Ozone at high concentration (6 ppm) caused a detrimental effect on eggshell quality. As a result, this study demonstrated that ozone treatments of 2, and especially 4 and 6 ppm concentration maintained eggshell quality during the storage. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  19. Effects of 0.12 and 0.80 ppm ozone on rat nasal and nasopharyngeal epithelial mucosubstances: Quantitative histochemistry

    International Nuclear Information System (INIS)

    Harkema, J.R.; Hotchkiss, J.A.; Henderson, R.F.

    1989-01-01

    The present study was designed to characterize the quantity of mucosubstances in surface epithelia of the rat nasal cavity and nasopharynx after short-term ozone exposure. Rats were exposure. Nasal cavities were processed for morphometric analysis of intraepithelial mucosubstances. Compared to controls, rats exposed to 0.12 ppm ozone had increased amounts of stored mucosubstances within epithelium lining the medial aspect of the nasal turbinate, but no change within the epithelium of the nasopharynx. Rats exposed to 0.8 ppm ozone had increased quantities of stored mucosubstances within the transitional and respiratory epithelia lining turbinates and lateral walls of the anterior nasal airway, and significant decreases in stored mucosubstances within the epithelium of the nasal septum at the end of exposure. Seven days after the end of exposure, the amounts of intraepithelial mucosubstances returned to control levels along the septum, but remained greater than those of controls along the turbinates and nasopharynx. We conclude that exposures to ambient levels of ozone induce significant changes in the stored secretory product of nasal epithelium in the rat, and that these changes persist for at least 7 days after cessation of exposure

  20. Inhaled ozone (O{sub 3})-induces changes in serum metabolomic and liver transcriptomic profiles in rats

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Desinia B. [Curriculum in Toxicology, University of North Carolina-Chapel Hill, Chapel Hill, NC (United States); Karoly, Edward D.; Jones, Jan C. [Metabolon Incorporation, Durham, NC (United States); Ward, William O.; Vallanat, Beena D.; Andrews, Debora L. [Research Cores Unit, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Schladweiler, Mette C.; Snow, Samantha J. [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Bass, Virginia L. [Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC (United States); Richards, Judy E.; Ghio, Andrew J.; Cascio, Wayne E.; Ledbetter, Allen D. [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States); Kodavanti, Urmila P., E-mail: kodavanti.urmila@epa.gov [Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC (United States)

    2015-07-15

    Air pollution has been linked to increased incidence of diabetes. Recently, we showed that ozone (O{sub 3}) induces glucose intolerance, and increases serum leptin and epinephrine in Brown Norway rats. In this study, we hypothesized that O{sub 3} exposure will cause systemic changes in metabolic homeostasis and that serum metabolomic and liver transcriptomic profiling will provide mechanistic insights. In the first experiment, male Wistar Kyoto (WKY) rats were exposed to filtered air (FA) or O{sub 3} at 0.25, 0.50, or 1.0 ppm, 6 h/day for two days to establish concentration-related effects on glucose tolerance and lung injury. In a second experiment, rats were exposed to FA or 1.0 ppm O{sub 3}, 6 h/day for either one or two consecutive days, and systemic metabolic responses were determined immediately after or 18 h post-exposure. O{sub 3} increased serum glucose and leptin on day 1. Glucose intolerance persisted through two days of exposure but reversed 18 h-post second exposure. O{sub 3} increased circulating metabolites of glycolysis, long-chain free fatty acids, branched-chain amino acids and cholesterol, while 1,5-anhydroglucitol, bile acids and metabolites of TCA cycle were decreased, indicating impaired glycemic control, proteolysis and lipolysis. Liver gene expression increased for markers of glycolysis, TCA cycle and gluconeogenesis, and decreased for markers of steroid and fat biosynthesis. Genes involved in apoptosis and mitochondrial function were also impacted by O{sub 3}. In conclusion, short-term O{sub 3} exposure induces global metabolic derangement involving glucose, lipid, and amino acid metabolism, typical of a stress–response. It remains to be examined if these alterations contribute to insulin resistance upon chronic exposure. - Highlights: • Ozone, an ubiquitous air pollutant induces acute systemic metabolic derangement. • Serum metabolomic approach provides novel insights in ozone-induced changes. • Ozone exposure induces leptinemia

  1. Ozone impact on vegetation: phenolic metabolism modification and oxidative alteration of Rubisco in Phaseolus vulgaris L; Impact de l'ozone sur le vegetal: modification du metabolisme phenolique et alteration de la Rubisco chez Phaseolus vulgaris L.

    Energy Technology Data Exchange (ETDEWEB)

    Kanoun, M.

    2002-04-15

    In order to characterize and quantify, in semi-natural situation, the incidence of atmospheric pollution on some physiological and metabolic functions in plants, the aim of our work was to identify sub-cellular impact markers, in bean (Phaseolus vulgaris L.), able to characterize a chronic and realistic ozone pollution climate. Two criteria were chosen: the foliar phenolic metabolism and the Rubisco, the key enzyme of photosynthesis. Using Open Top Chambers system, we demonstrated that, according to concentration, exposure kinetic and leaf type, ozone could induce amount variations of some constitutive soluble phenolic and the synthesis of new phenolic (iso-flavonoids). In some cases, these disturbances were observed jointly with foliar injuries and/or biomass reduction. Concurrently, this chronic and moderate ozone exposure could also induce carbonyl formation in amino acid residues constitutive of Rubisco small subunit (Rubisco-SSU) and a reduction in the amount of the native Rubisco. The amount of a constitutive kaempferol glucuronide and the ozone-induced oxidative alteration of Rubisco-SSU were selected and tested for the construction of dose-response relationships. Whatever the marker, the linear model was able to describe the relation. For the phenolic response, several exposure indexes were tested. According to their mode of calculation, these exposure forms emphasize more or less the contribution of high ozone concentrations. If, for Rubisco oxidation, the use of the exposure index AOT40 seems relevant, in the case of the phenolic marker, the choice of the right index is leaf type dependant. (author)

  2. Ozone exposure alters temporal fluctuations of 14C-labeled assimilate pools in leaves of Pinus taeda L

    International Nuclear Information System (INIS)

    Friend, A.L.; Tomlinson, P.T.

    1991-01-01

    The effects of O 3 on uptake and distribution of 14 C within current-year foliage of 3-year-old loblolly pine (Pinus taeda L.) seedlings were studied using open-top exposure chambers that delivered ozone at three concentrations: sub-ambient O 3 [charcoal-filtered air (CF)]; ambient O 3 (AMB); and twice-ambient O 3 (2X). Seedlings were exposed to O 3 from May to Oct. of 1987, 1988, and 1989. In July, Aug., and Sept. 1989, individual foliage fascicles were labeled with 14 CO 2 ; harvested at 0, 0.5, 4, 24, and 48h after labeling; and analyzed for 14 C in lipids and pigments, protein, starch, residue, sugars, organic acids, and amino acids. O 3 affected initial (0 h) incorporation of 14 C into different chemical fractions, and the relative distribution of 14 C among fractions at specific points in time. Starch dynamics were particularly responsive to and negatively affected by O 3 . In 2X treatments, only 39-46% of the initial (0 h) 14 C incorporated into starch remained after 48h, compared with a range of 56-90% remaining in CF treatments. The percentage of 14 C in the starch fraction after 48 h decreased by nearly three-fold in August from CF to 2X treatments [%total 14 C in starch: 31% (CF), 17% (AMB), and 11% (2X)]. The authors data indicated that foliar starch synthesis and/or retention was depressed by ozone exposure during late-season months, and supported the concept that O 3 decreases growth by depleting carbohydrate reserves. Other findings will be discussed

  3. Beginning of the ozone recovery over Europe? − Analysis of the total ozone data from the ground-based observations, 1964−2004

    Directory of Open Access Journals (Sweden)

    J. W. Krzyścin

    2005-07-01

    Full Text Available The total ozone variations over Europe (~50° N in the period 1964–2004 are analyzed for detection of signals of ozone recovery. The ozone deviations from the long-term monthly means (1964–1980 for selected European stations, where the ozone observations (by the Dobson spectrophotometers have been carried out continuously for at least 3–4 decades, are averaged and examined by a regression model. A new method is proposed to disclose both the ozone trend variations and date of the trend turnaround. The regression model contains a piecewise linear trend component and the terms describing the ozone response to forcing by "natural" changes in the atmosphere. Standard proxies for the dynamically driven ozone variations are used. The Multivariate Adaptive Regression Splines (MARS methodology and principal component analysis are used to find an optimal set of the explanatory variables and the trend pattern. The turnaround of the ozone trend in 1994 is suggested from the pattern of the piecewise linear trend component. Thus, the changes in the ozone mean level are calculated over the periods 1970–1994 and 1994–2003, for both the original time series and the time series having "natural" variations removed. Statistical significance of the changes are derived by bootstrapping. A first stage of recovery (according to the definition of the International Ozone Commission, i.e. lessening of a negative trend, is found over Europe. It seems possible that the increase in the ozone mean level since 1994 of about 1–2% is due to superposition of the "natural" processes. Comparison of the total ozone ground-based network (the Dobson and Brewer spectrophotometers and the satellite (TOMS, version 8 data over Europe shows the small bias in the mean values for the period 1996–2004, but the differences between the daily ozone values from these instruments are not trendless, and this may hamper an identification of the next stage of the ozone recovery over

  4. Monitoring ambient ozone with a passive measurement technique method, field results and strategy

    NARCIS (Netherlands)

    Scheeren, BA; Adema, EH

    1996-01-01

    A low-cost, accurate and sensitive passive measurement method for ozone has been developed and tested. The method is based on the reaction of ozone with indigo carmine which results in colourless reaction products which are detected spectrophotometrically after exposure. Coated glass filters are

  5. Ozone slows stomatal response to light and leaf wounding in a Mediterranean evergreen broadleaf, Arbutus unedo.

    Science.gov (United States)

    Paoletti, Elena

    2005-04-01

    The effect of a 90-d ozone exposure (charcoal-filtered air or 110 nmol mol(-1) O3) on stomatal conductance (gs) was investigated in the Mediterranean evergreen broadleaf Arbutus unedo L. Ozone did not significantly reduce midday steady-state gs compared to controls. However, it slowed stomatal response to abrupt reduction of light intensity and to increasing water stress, applied by severing the leaf midrib. Ozone slowed stomatal closure, rather than aperture. Nevertheless, vein-cutting did not allow ozonated leaves to reach the pre-injury gs levels, like controls did, suggesting re-opening was still, slowly in progress. The sluggish behaviour was recorded 10 days after cessation of O3 exposure ("memory effect") and may affect stomatal control in response to sunflecks and leaf wounding. Mediterranean evergreen broadleaves are regarded as tolerant to O3 exposure. Nevertheless, measurements of steady-state gs at midday may not account for altered stomatal responses to stressors.

  6. Estimation of surface UV levels based on Meteor-3/TOMS ozone data

    Energy Technology Data Exchange (ETDEWEB)

    Borisov, Y A [Central Aerological Observatory, Moscow (Russian Federation); Geogdzhaev, I V [Moscow Inst. of Physics and Technology, Moscow (Russian Federation); Khattatov, V U [Central Aerological Observatory, Moscow (Russian Federation)

    1996-12-31

    The major consequence of ozone layer depletion for the environment is an increase of harmful ultraviolet (UV) radiation on the Earth surface and in the upper ocean. This implies the importance of environmental UV monitoring. Since the direct global monitoring is not currently possible, indirect estimations of surface UV levels may be used based on satellite ozone data (Madronich, S. 1992). Total Ozone Mapping Spectrometer (TOMS) on board the METEOR-3 satellite provided regular set of data for such estimates. During the time of its operation (August, 1991 - December, 1994) the instrument registered several ozone hole events over Antarctica, when ozone levels dropped by as much as 60 % from their unperturbed values. Probably even more alarming ozone depletions were observed over highly populated regions of middle latitudes of northern hemisphere. Radiative transfer modeling was used to convert METEOR-3/TOMS daily ozone values into regional and global maps of biologically active UV. Calculations demonstrate the effect on surface UV levels produced by ozone hole over Antarctica and ozone depletions over the territory of Russia (March, 1994). UV contour lines deviate from the normal appearance which is determined by growing southward solar elevation. UV contour lines are almost perpendicular to the ozone ones in the ozone depletions areas. The 30 % ozone depletion, over Siberia caused more than 30 % increase in noontime erythemal UV levels, which is equivalent to 10-15 degrees southward latitude displacement. Higher UV radiation increases were found in ozone hole over South America (October 1992) equivalent to about 20 degrees southward displacement

  7. Estimation of surface UV levels based on Meteor-3/TOMS ozone data

    Energy Technology Data Exchange (ETDEWEB)

    Borisov, Y.A. [Central Aerological Observatory, Moscow (Russian Federation); Geogdzhaev, I.V. [Moscow Inst. of Physics and Technology, Moscow (Russian Federation); Khattatov, V.U. [Central Aerological Observatory, Moscow (Russian Federation)

    1995-12-31

    The major consequence of ozone layer depletion for the environment is an increase of harmful ultraviolet (UV) radiation on the Earth surface and in the upper ocean. This implies the importance of environmental UV monitoring. Since the direct global monitoring is not currently possible, indirect estimations of surface UV levels may be used based on satellite ozone data (Madronich, S. 1992). Total Ozone Mapping Spectrometer (TOMS) on board the METEOR-3 satellite provided regular set of data for such estimates. During the time of its operation (August, 1991 - December, 1994) the instrument registered several ozone hole events over Antarctica, when ozone levels dropped by as much as 60 % from their unperturbed values. Probably even more alarming ozone depletions were observed over highly populated regions of middle latitudes of northern hemisphere. Radiative transfer modeling was used to convert METEOR-3/TOMS daily ozone values into regional and global maps of biologically active UV. Calculations demonstrate the effect on surface UV levels produced by ozone hole over Antarctica and ozone depletions over the territory of Russia (March, 1994). UV contour lines deviate from the normal appearance which is determined by growing southward solar elevation. UV contour lines are almost perpendicular to the ozone ones in the ozone depletions areas. The 30 % ozone depletion, over Siberia caused more than 30 % increase in noontime erythemal UV levels, which is equivalent to 10-15 degrees southward latitude displacement. Higher UV radiation increases were found in ozone hole over South America (October 1992) equivalent to about 20 degrees southward displacement

  8. Comparative ozone responses of cutleaf coneflowers (Rudbeckia laciniata var. digitata, var. ampla) from Rocky Mountain and Great Smoky Mountains National Parks, USA.

    Science.gov (United States)

    Neufeld, Howard S; Johnson, Jennifer; Kohut, Robert

    2018-01-01

    Cutleaf coneflower (Rudbeckia laciniata L. var. digitata) is native to Great Smoky Mountains National Park (GRSM) and an ozone bioindicator species. Variety ampla, whose ozone sensitivity is less well known, is native to Rocky Mountain National Park (ROMO). In the early 2000s, researchers found putative ozone symptoms on var. ampla and rhizomes were sent to Appalachian State University to verify that the symptoms were the result of ozone exposure. In 2011, potted plants were exposed to ambient ozone from May to August. These same plants were grown in open-top chambers (OTCs) in 2012 and 2013, and exposed to charcoal-filtered (CF), non-filtered (NF), elevated ozone (EO), NF+50ppb in 2012 for 47days and NF+30/NF+50ppb ozone in 2013 for 36 and 36days, respectively. Ozone symptoms similar to those found in ROMO (blue-black adaxial stippling) were reproduced both in ambient air and in the OTCs. Both varieties exhibited foliar injury in the OTCs in an exposure-dependent manner, verifying that symptoms resulted from ozone exposure. In two of the three study years, var. digitata appeared more sensitive than var. ampla. Exposure to EO caused reductions in ambient photosynthetic rate (A) and stomatal conductance (g s ) for both varieties. Light response curves indicated that ozone reduced A, g s , and the apparent quantum yield while it increased the light compensation point. In CF air, var. ampla had higher light saturated A (18.2±1.04 vs 11.6±0.37μmolm -2 s -1 ), higher light saturation (1833±166.7 vs 1108±141.7μmolm -2 s -1 ), and lower Ci/Ca ratio (0.67±0.01 vs 0.77±0.01) than var. digitata. Coneflowers in both Parks are adversely affected by exposure to ambient ozone and if ozone concentrations increase in the Rocky Mountains, greater amounts of injury on var. ampla can be expected. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Surface ozone measurements in the southwest of the Iberian Peninsula (Huelva, Spain).

    Science.gov (United States)

    Carnero, Jose A Adame; Bolívar, Juan P; de la Morena, Benito A

    2010-02-01

    Photochemical ozone pollution of the lower troposphere (LT) is a very complex process involving meteorological, topographic emissions and chemical parameters. Ozone is considered the most important air pollutant in rural, suburban and industrial areas of many sites in the world since it strongly affects human health, vegetation and forest ecosystems, and its increase during the last decades has been significant. In addition, ozone is a greenhouse gas that contributes to climate change. For these reasons, it is necessary to carry out investigations that determine the behaviour of ozone at different locations. The aim of this work is to understand the levels and temporal variations of surface ozone in an industrial-urban region of the Southwest Iberian Peninsula. The study is based on ozone hourly data recorded during a 6-year period, 2000 to 2005 at four stations and meteorological data from a coastal station. The stations used were El Arenosillo and Cartaya--both coastal stations, Huelva--an urban site and Valverde--an inland station 50 km away from the coastline. The general characteristics of the ozone series, seasonal and daily ozone cycles as well as number of exceedances of the threshold established in the European Ozone Directive have been calculated and analysed. Analysis of the meteorological data shows that winter-autumn seasons are governed by the movement of synoptic weather systems; however, in the spring-summer seasons, both synoptic and mesoescale conditions exist. Average hourly ozone concentrations range from 78.5 +/- 0.1 microg m(-3) at Valverde to 57.8 +/- 0.2 microg m(-3) at Huelva. Ozone concentrations present a seasonal variability with higher values in summer months, while in wintertime, lower values are recorded. A seasonal daily evolution has also been found with minimum levels around 08:00 UTC, which occurs approximately 1-1.5 h after sunrise, whereas the maximum is reached at about 16:00 UTC. Furthermore, during summer, the maximum value

  10. Influence of ozone and paracetic acid disinfection on adhesion of resilient liners to acrylic resin.

    Science.gov (United States)

    Ekren, Orhun; Ozkomur, Ahmet

    2016-08-01

    The aim of this study was to evaluate the effect of paracetic acid (PAA) and ozone disinfection on the tensile bond strength (TBS) of silicone-based resilient liners to acrylic resins. One hundred and twenty dumbbell shaped heat-polymerized acrylic resins were prepared. From the mid segment of the specimens, 3 mm of acrylic were grinded off and separated parts were reattached by resilient liners. The specimens were divided into 2 control (control1, control7) and 4 test groups of PAA and ozone disinfection (PAA1, PAA7, ozone1 and ozone7; n=10). While control groups were immersed in distilled water for 10 min (control1) and 7 days (control7), test groups were subjected to PAA (16 g/L) or ozone rich water (4 mg/L) for 1 cycle (10 min for PAA and 60 min for ozone) per day for 7 days prior to tensile tests. Measurements of the TBS were analyzed using 3-way ANOVA and Tukey's HSD test. Adhesive strength of Mollosil decreased significantly by application of ozone disinfection. PAA disinfection had no negative effect on the TBS values of Mollosil and Molloplast B to acrylic resin. Single application of ozone disinfection did not have any negative effect on TBS values of Molloplast B, but prolonged exposure to ozone decreased its adhesive strength. The adhesion of resilient liners to acrylic was not adversely affected by PAA disinfection. Immersion in ozonated water significantly decreased TBS of Mollosil. Prolonged exposure to ozone negatively affects adhesion of Molloplast B to denture base materials.

  11. GSTM1 modulation of IL-8 expression in human epithelial cells exposed to ozone

    Science.gov (United States)

    Exposure to the major air pollutant ozone can aggravate asthma and other lung diseases. Our recent study in humanvolunteers hasshown that the glutathione S-transferase Mu 1(GSTMI)-null genotype is associated with increased airway neutrophilic inflammation induced by inhaled ozone...

  12. Is the ozone climate penalty robust in Europe?

    International Nuclear Information System (INIS)

    Colette, Augustin; Bessagnet, Bertrand; Meleux, Frédérik; Rouïl, Laurence; Andersson, Camilla; Engardt, Magnuz; Langner, Joakim; Baklanov, Alexander; Brandt, Jørgen; Christensen, Jesper H; Geels, Camilla; Hedegaard, Gitte B; Doherty, Ruth; Giannakopoulos, Christos; Katragkou, Eleni; Lei, Hang; Manders, Astrid; Melas, Dimitris; Sofiev, Mikhail; Soares, Joana

    2015-01-01

    Ozone air pollution is identified as one of the main threats bearing upon human health and ecosystems, with 25 000 deaths in 2005 attributed to surface ozone in Europe (IIASA 2013 TSAP Report #10). In addition, there is a concern that climate change could negate ozone pollution mitigation strategies, making them insufficient over the long run and jeopardising chances to meet the long term objective set by the European Union Directive of 2008 (Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008) (60 ppbv, daily maximum). This effect has been termed the ozone climate penalty. One way of assessing this climate penalty is by driving chemistry-transport models with future climate projections while holding the ozone precursor emissions constant (although the climate penalty may also be influenced by changes in emission of precursors). Here we present an analysis of the robustness of the climate penalty in Europe across time periods and scenarios by analysing the databases underlying 11 articles published on the topic since 2007, i.e. a total of 25 model projections. This substantial body of literature has never been explored to assess the uncertainty and robustness of the climate ozone penalty because of the use of different scenarios, time periods and ozone metrics. Despite the variability of model design and setup in this database of 25 model projection, the present meta-analysis demonstrates the significance and robustness of the impact of climate change on European surface ozone with a latitudinal gradient from a penalty bearing upon large parts of continental Europe and a benefit over the North Atlantic region of the domain. Future climate scenarios present a penalty for summertime (JJA) surface ozone by the end of the century (2071–2100) of at most 5 ppbv. Over European land surfaces, the 95% confidence interval of JJA ozone change is [0.44; 0.64] and [0.99; 1.50] ppbv for the 2041–2070 and 2071–2100 time windows, respectively

  13. Is the ozone climate penalty robust in Europe?

    Science.gov (United States)

    Colette, Augustin; Andersson, Camilla; Baklanov, Alexander; Bessagnet, Bertrand; Brandt, Jørgen; Christensen, Jesper H.; Doherty, Ruth; Engardt, Magnuz; Geels, Camilla; Giannakopoulos, Christos; Hedegaard, Gitte B.; Katragkou, Eleni; Langner, Joakim; Lei, Hang; Manders, Astrid; Melas, Dimitris; Meleux, Frédérik; Rouïl, Laurence; Sofiev, Mikhail; Soares, Joana; Stevenson, David S.; Tombrou-Tzella, Maria; Varotsos, Konstantinos V.; Young, Paul

    2015-08-01

    Ozone air pollution is identified as one of the main threats bearing upon human health and ecosystems, with 25 000 deaths in 2005 attributed to surface ozone in Europe (IIASA 2013 TSAP Report #10). In addition, there is a concern that climate change could negate ozone pollution mitigation strategies, making them insufficient over the long run and jeopardising chances to meet the long term objective set by the European Union Directive of 2008 (Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008) (60 ppbv, daily maximum). This effect has been termed the ozone climate penalty. One way of assessing this climate penalty is by driving chemistry-transport models with future climate projections while holding the ozone precursor emissions constant (although the climate penalty may also be influenced by changes in emission of precursors). Here we present an analysis of the robustness of the climate penalty in Europe across time periods and scenarios by analysing the databases underlying 11 articles published on the topic since 2007, i.e. a total of 25 model projections. This substantial body of literature has never been explored to assess the uncertainty and robustness of the climate ozone penalty because of the use of different scenarios, time periods and ozone metrics. Despite the variability of model design and setup in this database of 25 model projection, the present meta-analysis demonstrates the significance and robustness of the impact of climate change on European surface ozone with a latitudinal gradient from a penalty bearing upon large parts of continental Europe and a benefit over the North Atlantic region of the domain. Future climate scenarios present a penalty for summertime (JJA) surface ozone by the end of the century (2071-2100) of at most 5 ppbv. Over European land surfaces, the 95% confidence interval of JJA ozone change is [0.44; 0.64] and [0.99; 1.50] ppbv for the 2041-2070 and 2071-2100 time windows, respectively.

  14. Ozone depletion, related UVB changes and increased skin cancer incidence

    Science.gov (United States)

    Kane, R. P.

    1998-03-01

    Stratospheric ozone at middle latitudes shows a seasonal variation of about +/-20%, a quasi-biennial oscillation of 1-10% range and a long-term variation in which the level was almost steady up to about 1979 and declined thereafter to the present day by about 10%. These variations are expected to be reflected in solar UVB observed at the ground, but in an opposite direction. Thus UVB should have had a long-term increase of about 10-20%, which should cause an increase in skin cancer incidence of about 20-40%. Skin cancer incidence has increased all over the world, e.g. about 90% in USA during 1974-1990. It is popularly believed that this increase in skin cancer incidence is related to the recent ozone depletion. This seems to be incorrect, for two reasons. Firstly, the observed skin cancer increase is too large (90%) compared with the expected value (40%) from ozone depletion. Secondly, cancer does not develop immediately after exposure to solar UVB. The sunburns may occur within hours; but cancer development and detection may take years, even decades. Hence the observed skin cancer increase since 1974 (no data available for earlier periods) must have occurred due to exposure to solar UVB in the 1950s and 1960s, when there was no ozone depletion. Thus, the skin cancer increase must be attributed to harmful solar UVB levels existing even in the 1960s, accentuated later not by ozone depletion (which started only much later, by 1979) but by other causes, such as a longer human life span, better screening, increasing tendencies of sunbathing at beaches, etc., in affluent societies. On the other hand, the recent ozone depletion and the associated UVB increases will certainly take their toll; only that the effects will not be noticed now but years or decades from now. The concern for the future expressed in the Montreal Protocol for reducing ozone depletion by controlling CFC production is certainly justified, especially because increased UVB is harmful to animal and

  15. Modeling the effects of ozone on soybean growth and yield.

    Science.gov (United States)

    Kobayashi, K; Miller, J E; Flagler, R B; Heck, W W

    1990-01-01

    A simple mechanistic model was developed based on an existing growth model in order to address the mechanisms of the effects of ozone on growth and yield of soybean [Glycine max. (L.) Merr. 'Davis'] and interacting effects of other environmental stresses. The model simulates daily growth of soybean plants using environmental data including shortwave radiation, temperature, precipitation, irrigation and ozone concentration. Leaf growth, dry matter accumulation, water budget, nitrogen input and seed growth linked to senescence and abscission of leaves are described in the model. The effects of ozone are modeled as reduced photosynthate production and accelerated senescence. The model was applied to the open-top chamber experiments in which soybean plants were exposed to ozone under two levels of soil moisture regimes. After calibrating the model to the growth data and seed yield, goodness-of-fit of the model was tested. The model fitted well for top dry weight in the vegetative growth phase and also at maturity. The effect of ozone on seen yield was also described satisfactorily by the model. The simulation showed apparent interaction between the effect of ozone and soil moisture stress on the seed yield. The model revealed that further work is needed concerning the effect of ozone on the senescence process and the consequences of alteration of canopy microclimate by the open-top chambers.

  16. Ozone carcinogenesis in vitro and its co-carcinogenesis with radiation

    International Nuclear Information System (INIS)

    Borek, C.

    1988-01-01

    Ozone (O/sub 3/), a reactive species of oxygen, is an important natural constituent of the atmosphere. Background levels of ozone in the lower atmosphere may range up to 0.1 ppm and are modified by geographic elevation, solar radiation and climatic conditions. Since some ozone effects are radiomimetic, its actions may be enhanced in the presence of ionizing radiation from background and/or manmade sources. While stratospheric ozone spares the earth from excess solar ultraviolet (UV) radiation, high levels of ozone in the environment are toxic and present a health hazard to man. Excess environmental exposure to ozone can result from a variety of sources. Ozone is a key component in oxidant smog and in the vicinity of high electric voltage equipment when in operation. Ozone is widely used as a disinfectant for air and water, in bleaches, waxes, textiles, oils. and inorganic synthesis. Enhanced levels of ozone are found in planes flying at high altitudes. Because of the toxic nature of ozone and its potential hazard to man, its levels in the environment are subject to government regulation. The current standard is set at an hourly average of 235 μg/m/sup 3/ (0.12 ppm) not to be exceeded more than once per year. Urban areas with high levels of photochemical smog (e.g. Southern California) may experience high ambient ozone levels which can reach 0.5 ppm

  17. Physiological and biochemical stress responses in grassland species are influenced by both early-season ozone exposure and interspecific competition

    International Nuclear Information System (INIS)

    Scebba, Francesca; Canaccini, Francesca; Castagna, Antonella; Bender, Juergen; Weigel, Hans-Joachim; Ranieri, Annamaria

    2006-01-01

    The effects of two-year early season ozone exposure on physiological and biochemical stress response were investigated in model plant communities. Achillea millefolium and Veronica chamaedrys target plants were grown in monocultures and in mixed cultures with Poa pratensis (phytometer) and exposed in open-top chambers over two years for five weeks to charcoal-filtered (CF) air plus 25 nl l -1 O 3 (control) and non-filtered (NF) air plus 50 nl l -1 O 3 . Significant O 3 effects were detected in different physiological and biochemical parameters, evidencing interspecific differences in metabolic stress responses and a strong influence of the competition factor. O 3 induced strong oxidative effects in Achillea irrespective to the different growth modality. Veronica showed less O 3 -induced effects in monoculture than when grown in competition with the phytometer. Poa exhibited a different behaviour against O 3 depending on the species in competition, showing an overall higher sensitivity to O 3 when in mixture with Achillea. - The competition between species modulates the ozone effect in a short-term

  18. Physiological and biochemical stress responses in grassland species are influenced by both early-season ozone exposure and interspecific competition

    Energy Technology Data Exchange (ETDEWEB)

    Scebba, Francesca [Department of Agricultural Chemistry and Biotechnology, University of Pisa, Via del Borghetto 80, 56124 Pisa (Italy); Canaccini, Francesca [Department of Agricultural Chemistry and Biotechnology, University of Pisa, Via del Borghetto 80, 56124 Pisa (Italy); Castagna, Antonella [Department of Agricultural Chemistry and Biotechnology, University of Pisa, Via del Borghetto 80, 56124 Pisa (Italy); Bender, Juergen [Institute of Agroecology, FAL, Bundesallee 50, 38116 Braunschweig (Germany); Weigel, Hans-Joachim [Institute of Agroecology, FAL, Bundesallee 50, 38116 Braunschweig (Germany); Ranieri, Annamaria [Department of Agricultural Chemistry and Biotechnology, University of Pisa, Via del Borghetto 80, 56124 Pisa (Italy)]. E-mail: aranieri@agr.unipi.it

    2006-08-15

    The effects of two-year early season ozone exposure on physiological and biochemical stress response were investigated in model plant communities. Achillea millefolium and Veronica chamaedrys target plants were grown in monocultures and in mixed cultures with Poa pratensis (phytometer) and exposed in open-top chambers over two years for five weeks to charcoal-filtered (CF) air plus 25 nl l{sup -1} O{sub 3} (control) and non-filtered (NF) air plus 50 nl l{sup -1} O{sub 3}. Significant O{sub 3} effects were detected in different physiological and biochemical parameters, evidencing interspecific differences in metabolic stress responses and a strong influence of the competition factor. O{sub 3} induced strong oxidative effects in Achillea irrespective to the different growth modality. Veronica showed less O{sub 3}-induced effects in monoculture than when grown in competition with the phytometer. Poa exhibited a different behaviour against O{sub 3} depending on the species in competition, showing an overall higher sensitivity to O{sub 3} when in mixture with Achillea. - The competition between species modulates the ozone effect in a short-term.

  19. SPIROMETRIC RESPONSE TO OZONE (O3) IN YOUNG ADULTS AS A FUNCTION OF BODY MAASS INDEX (BMI)

    Science.gov (United States)

    Recent studies in murine models of obesity have shown enhanced responsiveness to ozone in obese vs. lean mice. To assess whether previous human ozone exposure data from our laboratory support an effect of BMI on the spirometric response to ozone we analyzed the post-O3 percent de...

  20. Ozone visible symptoms and reduced root biomass in the subalpine species Pinus uncinata after two years of free-air ozone fumigation

    International Nuclear Information System (INIS)

    Díaz-de-Quijano, Maria; Schaub, Marcus; Bassin, Seraina; Volk, Matthias; Peñuelas, Josep

    2012-01-01

    Concentrations of ozone often exceed the thresholds of forest protection in the Pyrenees, but the effect of ozone on Pinus uncinata, the dominant species in subalpine forests in this mountainous range, has not yet been studied. We conducted an experiment of free-air ozone fumigation with saplings of P. uncinata fumigated with ambient O 3 (AOT40 May–Oct: 9.2 ppm h), 1.5 × O 3amb (AOT40 May–Oct: 19.2 ppm h), and 1.8 × O 3amb (AOT40 May–Oct: 32.5 ppm h) during two growing seasons. We measured chlorophyll content and fluorescence, visible injury, gas exchange, and above- and below-ground biomass. Increased exposures to ozone led to a higher occurrence and intensity of visible injury from O 3 and a 24–29% reduction of root biomass, which may render trees more susceptible to other stresses such as drought. P. uncinata is thus a species sensitive to O 3 , concentrations of which in the Pyrenees are already likely affecting this species. - Highlights: ► We assessed sensitivity to O 3 in Pinus uncinata using a free-air O 3 fumigation system. ► Occurrence and intensity of visible injury from O 3 correlated with exposure to O 3 . ► Increased O 3 reduced root biomass 24–29%. ► O 3 weakens P. uncinata, making it more susceptible to other stresses. ► Ambient [O 3 ] in the Pyrenees is thus likely to already be affecting P. uncinata stands. - Ozone concentrations similar to those in the Pyrenees affect Pinus uncinata by reducing root biomass and possibly increasing susceptibility to other stresses.

  1. Ozone phytotoxicity evaluation and prediction of crops production in tropical regions

    Science.gov (United States)

    Mohammed, Nurul Izma; Ramli, Nor Azam; Yahya, Ahmad Shukri

    2013-04-01

    Increasing ozone concentration in the atmosphere can threaten food security due to its effects on crop production. Since the 1980s, ozone has been believed to be the most damaging air pollutant to crops. In Malaysia, there is no index to indicate the reduction of crops due to the exposure of ozone. Therefore, this study aimed to identify the accumulated exposure over a threshold of X ppb (AOTX) indexes in assessing crop reduction in Malaysia. In European countries, crop response to ozone exposure is mostly expressed as AOT40. This study was designed to evaluate and predict crop reduction in tropical regions and in particular, the Malaysian climate, by adopting the AOT40 index method and modifying it based on Malaysian air quality and crop data. Nine AOTX indexes (AOT0, AOT5, AOT10, AOT15, AOT20, AOT25, AOT30, AOT40, and AOT50) were analyzed, crop responses tested and reduction in crops predicted. The results showed that the AOT50 resulted in the highest reduction in crops and the highest R2 value between the AOT50 and the crops reduction from the linear regression analysis. Hence, this study suggests that the AOT50 index is the most suitable index to estimate the potential ozone impact on crops in tropical regions. The result showed that the critical level for AOT50 index if the estimated crop reduction is 5% was 1336 ppb h. Additionally, the results indicated that the AOT40 index in Malaysia gave a minimum percentage of 6% crop reduction; as contrasted with the European guideline of 5% (due to differences in the climate e.g., average amount of sunshine).

  2. Growth of Chironomus dilutus larvae exposed to ozone-treated and untreated oil sands process water

    International Nuclear Information System (INIS)

    Anderson, J.; Wiseman, S.; Franz, E.; Jones, P.; Liber, K.; Giesy, J.; Gamal El-Din, M.; Marin, J.

    2010-01-01

    Oil sand processing operations require large quantities of freshwater and produce large volumes of oil sands process water (OSPW) which must be stored on-site. This presentation reviewed various treatment methods for remediating OSPW in order to eliminate downstream toxicity. Naphthenic acids are the most important target fractions for treatment because they are primarily responsible for the acute toxicity of OSPW. Although ozonation has shown promise for reducing OSPW toxicity, the effects of ozonation on aquatic invertebrates remain unknown. This study investigated the effects of exposure to untreated and ozonated OSPW in Chironomus dilutus larvae. OSPW was treated with either a 50 or 80 mg O 3 /L dose of ozonation. The effects of ozonation levels on C. dilutus survival and growth were examined. The study showed that after a 10-day exposure, there were pronounced effects on survival of larvae exposed to ozone-treated or untreated OSPW. Larvae exposed to OSPW were 64-77 percent smaller than their respective controls, but the mean wet mass of organisms exposed to 50 mg O 3 /L ozonated OSPW was not much different from that of the controls. Larvae exposed to 80 mg O 3 /L ozone-treated OSPW were 40 percent smaller than the freshwater controls, and the mean wet mass was also much larger than the untreated OSPW. It was concluded that the toxicity of OSPW to benthic invertebrates may be reduced by ozone treatment.

  3. Improved functionality of graphene and carbon nanotube hybrid foam architecture by UV-ozone treatment

    Science.gov (United States)

    Wang, Wei; Ruiz, Isaac; Lee, Ilkeun; Zaera, Francisco; Ozkan, Mihrimah; Ozkan, Cengiz S.

    2015-04-01

    Optimization of the electrode/electrolyte double-layer interface is a key factor for improving electrode performance of aqueous electrolyte based supercapacitors (SCs). Here, we report the improved functionality of carbon materials via a non-invasive, high-throughput, and inexpensive UV generated ozone (UV-ozone) treatment. This process allows precise tuning of the graphene and carbon nanotube hybrid foam (GM) transitionally from ultrahydrophobic to hydrophilic within 60 s. The continuous tuning of surface energy can be controlled by simply varying the UV-ozone exposure time, while the ozone-oxidized carbon nanostructure maintains its integrity. Symmetric SCs based on the UV-ozone treated GM foam demonstrated enhanced rate performance. This technique can be readily applied to other CVD-grown carbonaceous materials by taking advantage of its ease of processing, low cost, scalability, and controllability.Optimization of the electrode/electrolyte double-layer interface is a key factor for improving electrode performance of aqueous electrolyte based supercapacitors (SCs). Here, we report the improved functionality of carbon materials via a non-invasive, high-throughput, and inexpensive UV generated ozone (UV-ozone) treatment. This process allows precise tuning of the graphene and carbon nanotube hybrid foam (GM) transitionally from ultrahydrophobic to hydrophilic within 60 s. The continuous tuning of surface energy can be controlled by simply varying the UV-ozone exposure time, while the ozone-oxidized carbon nanostructure maintains its integrity. Symmetric SCs based on the UV-ozone treated GM foam demonstrated enhanced rate performance. This technique can be readily applied to other CVD-grown carbonaceous materials by taking advantage of its ease of processing, low cost, scalability, and controllability. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr06795a

  4. Screening agrochemicals as potential protectants of plants against ozone phytotoxicity.

    Science.gov (United States)

    Saitanis, Costas J; Lekkas, Dimitrios V; Agathokleous, Evgenios; Flouri, Fotini

    2015-02-01

    We tested seven contemporary agrochemicals as potential plant protectants against ozone phytotoxicity. In nine experiments, Bel-W3 tobacco plants were experienced weekly exposures to a) 80 nmol mol(-1) of ozone-enriched or ozone-free air in controlled environment chambers, b) an urban air polluted area, and c) an agricultural-remote area. Ozone caused severe leaf injury, reduced chlorophylls' and total carotenoids' content, and negatively affected photosynthesis and stomatal conductance. Penconazole, (35% ± 8) hexaconazole (28% ± 5) and kresoxim-methyl (28% ± 15) showed higher plants' protection (expressed as percentage; mean ± s.e.) against ozone, although the latter exhibited a high variability. Azoxystrobin (21% ± 15) showed lower protection efficacy and Benomyl (15% ± 9) even lower. Trifloxystrobin (7% ± 11) did not protect the plants at all. Acibenzolar-S-methyl + metalaxyl-M (Bion MX) (-6% ± 17) exhibited the higher variability and contrasting results: in some experiments it showed some protection while in others it intensified the ozone injury by causing phytotoxic symptoms on leaves, even in control plants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Effect of ozone exposure on maximal airway narrowing in non-asthmatic and asthmatic subjects

    NARCIS (Netherlands)

    Hiltermann, T J; Stolk, J; Hiemstra, P S; Fokkens, P H; Rombout, P J; Sont, J K; Sterk, P J; Dijkman, J H

    1995-01-01

    1. Ozone is a major constituent of air pollution in the summer. Epidemiological studies have demonstrated that there is an increase in hospital admissions for respiratory diseases 1 day after peak levels of ambient ozone. This may be due to an increase in the responsiveness of the airways to

  6. Ozone alteration of membrane permeability in Chlorella. I. Permeability of potassium ion as measured by 86Rubidium tracer

    International Nuclear Information System (INIS)

    Heath, R.L.; Frederick, P.E.

    1979-01-01

    The addition of ozone to a suspension of Chlorella sorokiniana causes a rapid loss of K + , as measured by efflux of 86 Rb from prelabeled cells. The efflux of the tracer is stimulated some 15 to 20 times over that of the control. For about 100 microliters per liter ozone, about 25 minutes (6 x 10 -8 moles O 3 delivered per minute) of exposure are required for a 50% depletion of the intracellular K + . The stimulation of K + efflux is nearly linearly dependent upon the amount of ozone delivered into the solution. Following short pulses of ozone (lasting 1 to 5 minutes), efflux rates return to the control level but only after about 15 minutes. While influx of K + is ultimately inhibited by ozone, at low concentrations or for short exposure times the tracer influx is stimulated 100 to 200%. Ozone stimulation of an active pump mechanism is unlikely in view of a concomitant decrease in respiration. Thus, this influx may represent movement of K + along its electrochemical gradient. Assuming that influx and efflux are in steady-state according to the Goldman equation, it was calculated that the membrane potential for K + of -80 to -90 millivolts in control cells drops to -40 millivolts with ozone exposure and is accompanied by a calculated increased permeability to K + of 2- to 3-fold. 25 references, 6 figures

  7. Quantification of ozone uptake at the stand level in a Pinus canariensis forest in Tenerife, Canary Islands: An approach based on sap flow measurements

    International Nuclear Information System (INIS)

    Wieser, Gerhard; Luis, Vanessa C.; Cuevas, Emilio

    2006-01-01

    Ozone uptake was studied in a pine forest in Tenerife, Canary Islands, an ecotone with strong seasonal changes in climate. Ambient ozone concentration showed a pronounced seasonal course with high concentrations during the dry and warm period and low concentrations during the wet and cold season. Ozone uptake by contrast showed no clear seasonal trend. This is because canopy conductance significantly decreased with soil water availability and vapour pressure deficit. Mean daily ozone uptake averaged 1.9 nmol m -2 s -1 during the wet and cold season, and 1.5 nmol m -2 s -1 during the warm and dry period. The corresponding daily mean ambient ozone concentrations were 42 and 51 nl l -1 , respectively. Thus we conclude that in Mediterranean type forest ecosystems the flux based approach is more capable for risk assessment than an external, concentration based approach. - Sap flow measurements can be used for estimating ozone uptake at the stand level and for parameterisation of O 3 uptake models

  8. Effects of Acute Ozone Exposure and Methyl Jasmonate Treatment on White Pine Monoterpene and Sesquiterpene Emission Rates

    Science.gov (United States)

    Faiola, C. L.; Wagner, D.; Allwine, E.; Harley, P. C.; Vanreken, T. M.

    2010-12-01

    Biogenic volatile organic compounds (BVOCs) are produced by plants and include monoterpenes, sesquiterpenes, and their oxygenated derivatives. These BVOCs are one of the principal factors influencing the oxidative capacity of the atmosphere in forested regions, and impact both ozone concentration and secondary organic aerosol formation. Under unstressed conditions, the release of BVOCs to the atmosphere is primarily controlled by the vapor pressure of the relevant compounds within the plant tissue, which is in turn dependent on temperature as well as complex biochemical production processes. However, various natural and anthropogenic stressors can alter both the quantity and composition of the BVOCs emitted by plants. Many potential stressors are expected to become stronger as climate change effects escalate. The impacts of most stressors on BVOC emissions have not been well characterized, particularly in a field setting where changes in BVOC emissions could have influential feedbacks with climate. This study investigated the effects of two stressors on monoterpene and sesquiterpene emission rates at a field site in northern Michigan: acute ozone exposure and treatment with methyl jasmonate, an herbivory proxy. The study included six repetitions of the same experiment, each time using a new set of sub-canopy eastern white pine specimens. For each experiment, dynamic branch enclosures were simultaneously used on three specimens for sample collection: one ozone treatment tree, one methyl jasmonate treatment tree, and one control tree. Sampling lines were placed in each enclosure and VOCs were collected onto cartridges packed with Tenax GR adsorbent. Samples were collected several times per day for at least two days before treatment and for five days after treatment. Cartridges were analyzed via thermodesorption with an Agilent GC/MS/FID. This analysis allowed the identification and quantification of several monoterpene and sesquiterpene species in the samples

  9. Hypocotyl shape in radishes - a useful impact criterion for biological indication of ozone?; Hypokotyl-Form bei Radieschen - ein sinnvolles Wirkungskriterium fuer die Bioindikation von Ozon?

    Energy Technology Data Exchange (ETDEWEB)

    Kostka-Rick, R.

    1992-12-31

    A consistent correlation between certain `source` leaves and specific `sink` regions in the root of Beta vulgaris L. justifies to study the impact of ozone (O{sub 3}) on the shape of the hypocotyl in radish (Raphanus sativus L.) and the potential use of shape variants as effect criteria. A 7-day period of exposure to O{sub 3} ranging within realistic immission levels caused a nonsignificant reduction of hypocotyl fresh weight in radish. Two out three of the shape indices under study were also changed by ozone exposure - sometimes significantly. A discriminance function derived from several shape indices with or without fresh weight allowed a significant separation between the two O{sub 3}-treatment variants. Treatment with the anti-oxidant ethylene diurea (EDU) had no essential effect on hypocotyl shape. The author discusses the use of shape variants for ozone bio-indication. (orig.) [Deutsch] Eine konsistente Beziehung zwischen bestimmten `source`-Blaettern und spezifischen `sink`-Regionen in der Wurzel von Beta vulgaris L. rechtfertigt die Ueberpruefung des Einflusses von Ozon (O{sub 3}) auf die Form des Hypokotyls bei Radies (Raphanus sativus L.) und der potentiellen Nutzung von Formvariablen als Wirkungskriterium. Eine 7taegige O{sub 3}-Belastung im Bereich realistischer Immissionskonzentrationen verursachte eine nicht-signifikante Minderung des Hypokotyl-Frischgewichtes von Radies. Zwei von drei der untersuchten Formindizes wurden durch die Ozon-Belastung ebenfalls, z.T. signifikant, veraendert. Eine Diskriminanzfunktion aus mehreren Formindizes, mit oder ohne Einbeziehung des Frischgewichtes, gestattete eine signifikante Trennung zwischen den beiden O{sub 3}-Behandlungsvarianten. Eine Behandlung mit dem Anti-oxidants Ethylendiurea (EDU) hatte keinen wesentlichen Einfluss auf die Hypokotylform. Die Moeglichkeiten des Einsatzes von Formvariablen in der Bioindikation von Ozon werden diskutiert. (orig.)

  10. Exposure to air pollution is associated with lung hyperinflation in healthy children and adolescents in Southwest Mexico City: a pilot study.

    Science.gov (United States)

    Calderón-Garcidueñas, L; Mora-Tiscareño, A; Chung, C J; Valencia, G; Fordham, L A; García, R; Osnaya, N; Romero, L; Acuña, H; Villarreal-Calderón, A; Devlin, R B; Koren, H S

    2000-06-01

    Air pollution produces adverse health effects. The consequences of lifelong daily exposures to atmospheric pollutants upon the respiratory apparatus of healthy children are of considerable clinical importance. We investigated the association between exposure to a highly polluted urban environment with a complex mixture of air pollutants-ozone and particulate matter the predominant ones-and chest x-ray abnormalities in 59 healthy Mexican children who are lifelong residents of Southwest Metropolitan Mexico City (SWMMC), with a negative history of tobacco exposure and respiratory illnesses. Their clinical results and x-ray findings were compared to those of 19 Mexican control children, residents of a low-pollution area, with a similar negative history of tobacco exposure and respiratory illnesses. Ozone concentrations in SWMMC exceeded the U.S. Environmental Protection Agency (U.S. EPA) National Ambient Air Quality Standard (NAAQS) for O(3): 0.08 ppm as 1-h maximal concentration, not to be exceeded more than 4 times a year, on 71% of days in 1986 and 95% in 1997, with values as high as 0.48 ppm. Ozone maximal peaks are usually recorded between 2 and 5 pm coinciding with children's outdoor physical activities. Children in the control group reported no upper or lower respiratory symptomatology. Every SWMMC child complained of upper and/or lower respiratory symptoms, including epistaxis, nasal dryness and crusting, cough, shortness of breath, and chest discomfort. Children aged 7-13 yr had the most symptomatology, while 5- to 6-year olds and adolescents with the lowest number of statistically significant outdoor exposure hours had less respiratory symptoms. Bilateral symmetric mild lung hyperinflation was significantly associated with exposure to the SWMMC atmosphere (p = .0004). Chronic and sustained inhalation of a complex mixture of air pollutants, including ozone and particulate matter (PM), is associated with lung hyperinflation, suggestive of small airway disease

  11. Adaptation of the pituitary-adrenal axis to daily repeated forced swim exposure in rats is dependent on the temperature of water.

    Science.gov (United States)

    Rabasa, Cristina; Delgado-Morales, Raúl; Gómez-Román, Almudena; Nadal, Roser; Armario, Antonio

    2013-11-01

    Comparison of exposure to certain predominantly emotional stressors reveals a qualitatively similar neuroendocrine response profile as well as a reduction of physiological responses after daily repeated exposure (adaptation). However, particular physical components of the stressor may interfere with adaptation. As defective adaptation to stress can enhance the probability to develop pathologies, we studied in adult male rats (n = 10/group) swimming behavior (struggling, immobility and mild swim) and physiological responses (ACTH, corticosterone and rectal temperature) to daily repeated exposure to forced swim (20 min, 13 d) at 25 or 36 °C (swim25 or swim36). Rats were repeatedly blood-sampled by tail-nick and hormones measured by radioimmunoassay. Some differences were observed between the two swim temperature groups after the first exposure to forced swim: (a) active behaviors were greater in swim25 than swim36 groups; (b) swim25 but not swim36 caused hypothermia; and (c) swim36 elicited the same ACTH response as swim25, but plasma corticosterone concentration was lower for swim36 at 30 min post-swim. After daily repeated exposure, adaptation in ACTH secretion was observed with swim36 already on day 4, whereas with swim25 adaptation was not observed until day 13 and was of lower magnitude. Nevertheless, after repeated exposure to swim25 a partial protection from hypothermia was observed and the two swim conditions resulted in progressive reduction of active behaviors. Thus, daily repeated swim at 25 °C impairs adaptation of the hypothalamic-pituitary-adrenal axis as compared to swim at 36 °C, supporting the hypothesis that certain physical components of predominantly emotional stressors can interfere with the process of adaptation.

  12. Unequivocal detection of ozone recovery in the Antarctic Ozone Hole through significant increases in atmospheric layers with minimum ozone

    Science.gov (United States)

    de Laat, Jos; van Weele, Michiel; van der A, Ronald

    2015-04-01

    An important new landmark in present day ozone research is presented through MLS satellite observations of significant ozone increases during the ozone hole season that are attributed unequivocally to declining ozone depleting substances. For many decades the Antarctic ozone hole has been the prime example of both the detrimental effects of human activities on our environment as well as how to construct effective and successful environmental policies. Nowadays atmospheric concentrations of ozone depleting substances are on the decline and first signs of recovery of stratospheric ozone and ozone in the Antarctic ozone hole have been observed. The claimed detection of significant recovery, however, is still subject of debate. In this talk we will discuss first current uncertainties in the assessment of ozone recovery in the Antarctic ozone hole by using multi-variate regression methods, and, secondly present an alternative approach to identify ozone hole recovery unequivocally. Even though multi-variate regression methods help to reduce uncertainties in estimates of ozone recovery, great care has to be taken in their application due to the existence of uncertainties and degrees of freedom in the choice of independent variables. We show that taking all uncertainties into account in the regressions the formal recovery of ozone in the Antarctic ozone hole cannot be established yet, though is likely before the end of the decade (before 2020). Rather than focusing on time and area averages of total ozone columns or ozone profiles, we argue that the time evolution of the probability distribution of vertically resolved ozone in the Antarctic ozone hole contains a better fingerprint for the detection of ozone recovery in the Antarctic ozone hole. The advantages of this method over more tradition methods of trend analyses based on spatio-temporal average ozone are discussed. The 10-year record of MLS satellite measurements of ozone in the Antarctic ozone hole shows a

  13. Predicting community sensitivity to ozone, using Ellenberg Indicator values

    Energy Technology Data Exchange (ETDEWEB)

    Jones, M. Laurence M. [Centre for Ecology and Hydrology Bangor, Orton Building, Deiniol Road, Bangor, Gwynedd LL57 2UP (United Kingdom)]. E-mail: lj@ceh.ac.uk; Hayes, Felicity [Centre for Ecology and Hydrology Bangor, Orton Building, Deiniol Road, Bangor, Gwynedd LL57 2UP (United Kingdom)]. E-mail: fhay@ceh.ac.uk; Mills, Gina [Centre for Ecology and Hydrology Bangor, Orton Building, Deiniol Road, Bangor, Gwynedd LL57 2UP (United Kingdom)]. E-mail: gmi@ceh.ac.uk; Sparks, Tim H. [Centre for Ecology and Hydrology Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS (United Kingdom)]. E-mail: ths@ceh.ac.uk; Fuhrer, Juerg [Swiss Federal Research Station for Agroecology and Agriculture (FAL), Air Pollution/Climate Group, Reckenholzstrasse 191, CH-8046 Zurich (Switzerland)]. E-mail: juerg.fuhrer@fal.admin.ch

    2007-04-15

    This paper develops a regression-based model for predicting changes in biomass of individual species exposed to ozone (RS{sub p}), based on their Ellenberg Indicator values. The equation (RS{sub p}=1.805-0.118Light-0.135Salinity) underpredicts observed sensitivity but has the advantage of widespread applicability to almost 3000 European species. The model was applied to grassland communities to develop two further predictive tools. The first tool, percentage change in biomass (ORI%) was tested on data from a field-based ozone exposure experiment and predicted a 27% decrease in biomass over 5 years compared with an observed decrease of 23%. The second tool, an index of community sensitivity to ozone (CORI), was applied to 48 grassland communities and suggests that community sensitivity to ozone is primarily species-driven. A repeat-sampling routine showed that nine species were the minimum requirement to estimate CORI within 5%.

  14. A DIGE analysis of developing poplar leaves subjected to ozone reveals major changes in carbon metabolism.

    Science.gov (United States)

    Bohler, Sacha; Bagard, Matthieu; Oufir, Mouhssin; Planchon, Sébastien; Hoffmann, Lucien; Jolivet, Yves; Hausman, Jean-François; Dizengremel, Pierre; Renaut, Jenny

    2007-05-01

    Tropospheric ozone pollution is described as having major negative effects on plants, compromising plant survival. Carbon metabolism is especially affected. In the present work, the effects of chronic ozone exposure were evaluated at the proteomic level in developing leaves of young poplar plants exposed to 120 ppb of ozone for 35 days. Soluble proteins (excluding intrinsic membrane proteins) were extracted from leaves after 3, 14 and 35 days of ozone exposure, as well as 10 days after a recovery period. Proteins (pI 4 to 7) were analyzed by 2-D DIGE experiments, followed by MALDI-TOF-TOF identification. Additional observations were obtained on growth, lesion formation, and leaf pigments analysis. Although treated plants showed large necrotic spots and chlorosis in mature leaves, growth decreased only slightly and plant height was not affected. The number of abscised leaves was higher in treated plants, but new leaf formation was not affected. A decrease in chlorophylls and lutein contents was recorded. A large number of proteins involved in carbon metabolism were identified. In particular, proteins associated with the Calvin cycle and electron transport in the chloroplast were down-regulated. In contrast, proteins associated with glucose catabolism increased in response to ozone exposure. Other identified enzymes are associated with protein folding, nitrogen metabolism and oxidoreductase activity.

  15. Pulmonary and symptom threshold effects of ozone in airline passenger and cockpit crew surrogates

    Energy Technology Data Exchange (ETDEWEB)

    Lategola, M.T.; Melton, C.E.; Higgins, E.A.

    1980-09-01

    Previous studies showed that the ozone concentration for pulmonary and symptom threshold effects in flight attendant surrogates lies between 0.20 and 0.30 ppMv for a 3-h exposure with intermittent treadmill exercise at 1829 m (MSL) stimulated cabin altitude. In the present study of sedentary occupants of the in-flight airline cabin, the same protocol was used except for omitting all treadmill exercise. Symptoms were assessed with a standardized questionnaire. Pulmonary function was assessed using standardized quantitative spirometry. Male smoker and nonsmoker airline passenger and cockpit crew surrogates 40 to 59 years of age were used. Small but statistically significant displacements occurred in symptoms and in some spirometry parameters. In general, the younger subjects appeared more sensitive to ozone than the older subjects. No significant differences appeared between smokers' and nonsmokers' responses to ozone exposure. It is concluded that the ozone threshold of these sedentary surrogates under these experimental conditions is right at 0.30 ppMv.

  16. Ozonation for source treatment of pharmaceuticals in hospital wastewater - ozone lifetime and required ozone dose

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Spiliotopoulou, Aikaterini; Chhetri, Ravi Kumar

    2016-01-01

    Ozonation aimed at removing pharmaceuticals was studied in an effluent from an experimental pilot system using staged moving bed biofilm reactor (MBBR) tanks for the optimal biological treatment of wastewater from a medical care unit of Aarhus University Hospital. Dissolved organic carbon (DOC......) and pH in samples varied considerably, and the effect of these two parameters on ozone lifetime and the efficiency of ozone in removing pharmaceuticals were determined. The pH in the effluent varied from 5.0 to 9.0 resulting in approximately a doubling of the required ozone dose at the highest p......H for each pharmaceutical. DOC varied from 6 to 20 mg-DOC/L. The ozone required for removing each pharmaceutical, varied linearly with DOC and thus, ozone doses normalized to DOC (specific ozone dose) agreed between water samples (typically within 15%). At neutral pH the specific ozone dose required...

  17. Ozone response to emission changes: a modeling study during the MCMA-2006/MILAGRO Campaign

    Directory of Open Access Journals (Sweden)

    J. Song

    2010-04-01

    Full Text Available The sensitivity of ozone production to precursor emissions was investigated under five different meteorological conditions in the Mexico City Metropolitan Area (MCMA during the MCMA-2006/MILAGRO field campaign using the gridded photochemical model CAMx driven by observation-nudged WRF meteorology. Precursor emissions were constrained by the comprehensive data from the field campaign and the routine ambient air quality monitoring network. Simulated plume mixing and transport were examined by comparing with measurements from the G-1 aircraft during the campaign. The observed concentrations of ozone precursors and ozone were reasonably well reproduced by the model. The effects of reducing precursor emissions on urban ozone production were performed for three representative emission control scenarios. A 50% reduction in VOC emissions led to 7 to 22 ppb decrease in daily maximum ozone concentrations, while a 50% reduction in NOx emissions leads to 4 to 21 ppb increase, and 50% reductions in both NOx and VOC emission decrease the daily maximum ozone concentrations up to 10 ppb. These results along with a chemical indicator analysis using the chemical production ratios of H2O2 to HNO3 demonstrate that the MCMA urban core region is VOC-limited for all meteorological episodes, which is consistent with the results from MCMA-2003 field campaign; however the degree of the VOC-sensitivity is higher during MCMA-2006 due to lower VOCs, lower VOC reactivity and moderately higher NOx emissions. Ozone formation in the surrounding mountain/rural area is mostly NOx-limited, but can be VOC-limited, and the range of the NOx-limited or VOC-limited areas depends on meteorology.

  18. Pre-Altitude Serum Ferritin Levels and Daily Oral Iron Supplement Dose Mediate Iron Parameter and Hemoglobin Mass Responses to Altitude Exposure.

    Directory of Open Access Journals (Sweden)

    Andrew D Govus

    Full Text Available To investigate the influence of daily oral iron supplementation on changes in hemoglobin mass (Hbmass and iron parameters after 2-4 weeks of moderate altitude exposure.Hematological data collected from 178 athletes (98 males, 80 females exposed to moderate altitude (1,350-3,000 m were analysed using linear regression to determine how altitude exposure combined with oral iron supplementation influenced Hbmass, total iron incorporation (TII and blood iron parameters [ferritin and transferrin saturation (TSAT].Altitude exposure (mean ± s: 21 ± 3 days increased Hbmass by 1.1% [-0.4, 2.6], 3.3% [1.7, 4.8], and 4.0% [2.0, 6.1] from pre-altitude levels in athletes who ingested nil, 105 mg and 210 mg respectively, of oral iron supplement daily. Serum ferritin levels decreased by -33.2% [-46.9, -15.9] and 13.8% [-32.2, 9.7] from pre-altitude levels in athletes who supplemented with nil and 105 mg of oral iron supplement daily, but increased by 36.8% [1.3, 84.8] in athletes supplemented with 210 mg of oral iron daily. Finally, athletes who ingested either 105 mg or 210 mg of oral iron supplement daily had a greater TII compared with non-supplemented athletes (0 versus 105 mg: effect size (d = -1.88 [-2.56, -1.17]; 0 versus 210 mg: effect size (d = -2.87 [-3.88, -1.66].Oral iron supplementation during 2-4 weeks of moderate altitude exposure may enhance Hbmass production and assist the maintenance of iron balance in some athletes with low pre-altitude iron stores.

  19. Ozone induced leaf loss and decreased leaf production of European Holly (Ilex aquifolium L.) over multiple seasons

    International Nuclear Information System (INIS)

    Ranford, Jonathan; Reiling, Kevin

    2007-01-01

    European Holly (Ilex aquifolium L.) was used to study the impact of one short (28 day) ozone fumigation episode on leaf production, leaf loss and stomatal conductance (g s ), in order to explore potential longer term effects over 3 growing seasons. Young I. aquifolium plants received an episode of either charcoal-filtered air or charcoal-filtered air with 70 nl l -1 O 3 added for 7 h d -1 over a 28 day period from June 15th 1996, then placed into ambient environment, Stoke-on-Trent, U.K. Data were collected per leaf cohort over the next three growing seasons. Ozone exposure significantly increased leaf loss and stomatal conductance and reduced leaf production over all subsequent seasons. Impact of the initial ozone stress was still detected in leaves that had no direct experimental ozone exposure. This study has shown the potential of ozone to introduce long-term phenological perturbations into ecosystems by influencing productivity over a number of seasons. - Ozone significantly alters Ilex aquifolium leaf production and loss over multiple seasons

  20. Fumigation characteristics of ozone in postharvest treatment of Kabkab dates (Phoenix dactylifera L.) against selected insect infestation.

    Science.gov (United States)

    Niakousari, Mehrdad; Erjaee, Zahra; Javadian, Shahram

    2010-04-01

    Methyl bromide fumigation, the most accepted quarantine treatment for dates and many other dried commodities, will be phased out by 2015 worldwide. As a result, there is a critical need to develop durable alternatives for methyl bromide as postharvest treatments of agricultural commodities. This article presents a new method for postharvest treatment of Kabkab dates (Phoenix dactylifera L.) by application of gaseous ozone to reduce or eliminate all life stages (adults, larvae, and eggs) of Indian meal moth (Plodia interpunctella) and sawtooth grain beetle (Oryzaephilus surinamensis). The effect of the ozonation process on the sugar content of dates was also evaluated. Infested dates were exposed to ozone concentrations of 600, 1,200, 2,000, and 4,000 ppm for 1 and 2 h. As insect eggs are known to be most tolerant to many chemical or physical treatments, they were additionally exposed to an atmosphere of pure carbon dioxide prior to ozonation. Exposing samples to ozone concentrations of >2,000 ppm for 2 h resulted in complete mortality of larvae and adults. Exposure to 4,000 ppm of ozone for 2 h resulted in 80% mortality of eggs, and exposure to CO(2) prior to ozonation did not improve the effect of ozonation on eggs. Ozone did not have any influence on the sugar content of Kabkab dates.

  1. CARRY-OVER EFFECTS OF OZONE ON ROOT GROWTH AND CARBOHYDRATE CONCENTRATIONS OF PONDEROSA PINE SEEDLINGS

    Science.gov (United States)

    Ozone exposure decreases belowground carbon allocation and root growth of plants;however,the extent to which these effects persist and the cumulative impact of ozone stress on plant growth are poorly understood.To evaluate the potential for plant compensation,we followed the prog...

  2. Shelf life characteristics of bread produced from ozonated wheat flour.

    Science.gov (United States)

    Obadi, Mohammed; Zhu, Ke-Xue; Peng, Wei; Sulieman, Abdellatif A; Mahdi, Amer Ali; Mohammed, Khalid; Zhou, Hui-Ming

    2017-11-13

    The objective of this work was to study the effect of ozone treatment on the quality of bread and its shelf life. Flour was treated with ozone gas a rate of 5 L/min for 5, 15, 25, 35, and 45 min. Baking studies showed that bread made from flour treated with ozone for 15 min exhibited improved quality properties (in terms of specific volume, bread color, and crumb cell numbers). Exposure to ozone for shorter times did not cause obvious changes in the major volatile compounds of bread. A shelf life tests showed that ozone gas treatment influenced the extent of starch crystallinity. The relative starch crystallinity of bread made from flour treated with ozone for 15 min was lower than the control value, as were the hardness, springiness, and cohesiveness. Microscopic examination of crumb structure revealed remarkable differences between control and treated breads. Although ozone is a naturally occurring substance found in the atmosphere, ozone can also be produced synthetically. Recently, ozone has come to be regarded as a new treatment for flour. Especially in countries where the chlorination is forbidden, ozone treatment may be of a great interest if it were associated with significant and reliable changes in flour. Ozone treatment of wheat flour tends to improve bread shelf life and quality in terms of physiochemical, baking properties, X-ray diffraction data, volatile compound levels, crumb structure, and textural characteristics. Given such findings, desirable shelf life and bread qualities may be achieved when ozone is used as a flour oxidant prior to bread baking. Analyses of the effects of ozone gas on treatment of flour on bread shelf life and quality would aid the production of high quality and extend the shelf life of bread. © 2017 Wiley Periodicals, Inc.

  3. Exposure information in environmental health research: Current opportunities and future directions for particulate matter, ozone, and toxic air pollutants

    Energy Technology Data Exchange (ETDEWEB)

    McKone, Thomas E.; Ryan, P. Barry; Ozkaynak, Haluk

    2007-02-01

    Understanding and quantifying outdoor and indoor sources of human exposure are essential but often not adequately addressed in health-effects studies for air pollution. Air pollution epidemiology, risk assessment, health tracking and accountability assessments are examples of health-effects studies that require but often lack adequate exposure information. Recent advances in exposure modeling along with better information on time-activity and exposure factors data provide us with unique opportunities to improve the assignment of exposures for both future and ongoing studies linking air pollution to health impacts. In September 2006, scientists from the US Environmental Protection Agency (EPA) and the Centers for Disease Control and Prevention (CDC) along with scientists from the academic community and state health departments convened a symposium on air pollution exposure and health in order to identify, evaluate, and improve current approaches for linking air pollution exposures to disease. This manuscript presents the key issues, challenges and recommendations identified by the exposure working group, who used cases studies of particulate matter, ozone, and toxic air pollutant exposure to evaluate health-effects for air pollution. One of the over-arching lessons of this workshop is that obtaining better exposure information for these different health-effects studies requires both goal-setting for what is needed and mapping out the transition pathway from current capabilities to meeting these goals. Meeting our long-term goals requires definition of incremental steps that provide useful information for the interim and move us toward our long-term goals. Another over-arching theme among the three different pollutants and the different health study approaches is the need for integration among alternate exposure assessment approaches. For example, different groups may advocate exposure indicators, biomonitoring, mapping methods (GIS), modeling, environmental media

  4. Breaks induced in the deoxyribonucleic acid of aerosolized Escherichia coli by ozonized cyclohexene.

    Science.gov (United States)

    De Mik, G; De Groot, I

    1978-01-01

    The inactivation of aerosolized Escherichia coli by ozone, cyclohexene, and ozonized cyclohexene was studied. The parameters for damage were loss of reproduction and introduction of breaks in the deoxyribonucleic acid (DNA). Aerosolization of E. coli in clean air at 80 percent relative humidity or in air containing either ozone or cyclohexene hardly affected survival; however, some breaks per DNA molecule were induced, as shown by sucrose gradient sedimentation of the DNA. Aerosolization of E. coli in air containing ozonized cyclohexene at 80 percent relative humidity decreased the survival by a factor of 10(3) or more after 1 h of exposure and induced many breaks in the DNA. PMID:341811

  5. Investigating ozone-induced decomposition of surface-bound permethrin for conditions in aircraft cabins.

    Science.gov (United States)

    Coleman, B K; Wells, J R; Nazaroff, W W

    2010-02-01

    The reaction of ozone with permethrin can potentially form phosgene. Published evidence on ozone levels and permethrin surface concentrations in aircraft cabins indicated that significant phosgene formation might occur in this setting. A derivatization technique was developed to detect phosgene with a lower limit of detection of 2 ppb. Chamber experiments were conducted with permethrin-coated materials (glass, carpet, seat fabric, and plastic) exposed to ozone under cabin-relevant conditions (150 ppb O(3), 4.5/h air exchange rate, means of material-balance modeling indicates that the upper limit on the phosgene level in aircraft cabins resulting from this chemistry is approximately 1 microg/m(3) or approximately 0.3 ppb. It was thus determined that phosgene formation, if it occurs in aircraft cabins, is not likely to exceed relevant, health-based phosgene exposure guidelines. Phosgene formation from ozone-initiated oxidation of permethrin in the aircraft cabin environment, if it occurs, is estimated to generate levels below the California Office of Environmental Health Hazard Assessment acute reference exposure level of 4 microg/m(3) or approximately 1 ppb.

  6. Tobacco clones derived from tissue culture with supersensitivity to ozone

    International Nuclear Information System (INIS)

    Sun, E.J.; Kang, H.W.

    2003-01-01

    New tobacco clones supersensitive to ozone were obtained from tissue culture. - At least two supersensitive tobacco somaclones were obtained from tissue culture (TC) , when this approach was used to asexually propagate Bel-W3 tobacco indicator plants. These somaclones can detect as low as 30 ppb ozone for a 4-h exposure duration both within CSTR exposure chambers and in ambient air. Comparison of the injury index and their coefficient of variance showed that the TC plantlets usually have more uniform performance in response to ozone in addition to their higher sensitivity. A quick regeneration procedure was established to preserve the supersensitive germplasm immediately when it was found. The TC plantlets will flower and produce seed similar to seed-grown tobacco. The TC approach proved to be a better propagation system for valuable indicator plant species. The mechanism that causes the variation and the possible difference in their genome from seed-grown tobacco is still unknown. Further studies are needed in the future to determine if factors in the TC system may be responsible for the sensitivity difference

  7. Solar UV radiation exposure of seamen - Measurements, calibration and model calculations of erythemal irradiance along ship routes

    Energy Technology Data Exchange (ETDEWEB)

    Feister, Uwe [German Meteorological Service, Meteorological Observatory Lindenberg - Richard-Assmann-Observatory, Am Observatorium 12, 15848 Lindenberg (Germany); Meyer, Gabriele; Kirst, Ulrich [German Social Accident Insurance Institution for Transport and Traffic, Ottenser Hauptstrasse 54, 22765 Hamburg (Germany)

    2013-05-10

    Seamen working on vessels that go along tropical and subtropical routes are at risk to receive high doses of solar erythemal radiation. Due to small solar zenith angles and low ozone values, UV index and erythemal dose are much higher than at mid-and high latitudes. UV index values at tropical and subtropical Oceans can exceed UVI = 20, which is more than double of typical mid-latitude UV index values. Daily erythemal dose can exceed the 30-fold of typical midlatitude winter values. Measurements of erythemal exposure of different body parts on seamen have been performed along 4 routes of merchant vessels. The data base has been extended by two years of continuous solar irradiance measurements taken on the mast top of RV METEOR. Radiative transfer model calculations for clear sky along the ship routes have been performed that use satellite-based input for ozone and aerosols to provide maximum erythemal irradiance and dose. The whole data base is intended to be used to derive individual erythemal exposure of seamen during work-time.

  8. Potential of ozone as a fumigant to control pests in honey bee (Hymenoptera: Apidae) hives.

    Science.gov (United States)

    James, R R

    2011-04-01

    Ozone is a powerful oxidant capable of killing insects and microorganisms, and eliminating odors, taste, and color. Thus, it could be useful as a fumigant to decontaminate honey comb between uses. The experiments here are intended to determine the exposure levels required to kill an insect pest and spore forming bee pathogens. Ozone was effective against greater wax moth, Galleria mellonella (L.) (Lepidoptera: Pyralidae), even on naturally infested comb. Neonates and adults were the easiest life stages to kill, requiring only a few hours of exposure, whereas eggs required a 48-h exposure (at 460-920 mg O3/m3). Two honey bee, Apis mellifera L. (Hymenoptera: Apidae), pathogens, Ascosphaera apis (a fungus that causes chalkbrood) and Paenibacillus larvae (a bacterium that causes American foulbrood), also were killed with ozone. These pathogens required much higher concentrations (3200 and 8560 mg O3/m3, respectively) and longer exposure periods (3 d) than needed to control the insects. P. larvae was effectively sterilized only when these conditions were combined with high temperature (50 degrees C) and humidity (> or =75% RH). Thus, ozone shows potential as a fumigant for bee nesting materials, but further research is needed to evaluate its acceptability and efficacy in the field. The need for a reliable method to decontaminate honey bee nesting materials as part of an overall bee health management system is discussed.

  9. Stomata open at night in pole-sized and mature ponderosa pine: implications for O{sub 3} exposure metrics

    Energy Technology Data Exchange (ETDEWEB)

    Grulke, N. E.; Alonso, R.; Nguyen, T.; Dobrowolski, W. [USDA Forest Service, Pacific Southwest Station, Riverside, CA (United States); Cascio, C. [University of Florence, Firenze (Italy)

    2004-09-01

    Nighttime stomatal behaviour in two tree size stands of ponderosa pine are described. Ponderosa pine is one of the most ozone-sensitive conifers in western North America. The study involved measurement of time required to reach equilibrium in response to small increases in low irradiances at sites differing in environmental stressors. The contribution of nighttime ozone uptake to total daily ozone uptake in early and later summer was also investigated. Nighttime stomata conductance ranged between one tenth and one fifth that of maximum day-time values. Pole-size trees (i.e. less than 40 years old) showed greater ozone conductance than mature trees (i.e. over 250 years old). In June, nighttime ozone uptake accounted for 9, 5, and 3 per cent of the total daily ozone uptake of pole-sized trees. In late summer, ozone uptake at night was less than two percent of daily uptake at all sites. It is suspected that nighttime uptake of oxidants may have harmful physiological effects, such as contributing to the declining health of forest trees, owing to the fact that oxidants absorbed at night are not detoxified as well during the day. 67 refs.,1 tab., 8 figs.

  10. Ozonated water in the post-harvest treatment of coffee fruits

    Directory of Open Access Journals (Sweden)

    Fernando J. B. Brandão

    Full Text Available ABSTRACT Ozone is used in many countries for the treatment of effluents, becoming a viable alternative in sanitation of coffee wastewater. However, the strong ozone oxidation, responsible for its germicidal effect, can also compromise grain and beverage quality. The objective of this study was to evaluate the quality of Arabica coffee in different periods of treatment with ozonated water and its effect after drying. Coffee fruits were subjected to ozonation at regular intervals of 0, 5, 10, 20, and 30 min, with continuous stirring promoted by a recirculating water system at constant rate of 1 ppm of solubilized ozone. The design was completely randomized with five treatments and four replicates. After obtaining the data, the analysis of variance was performed and means were compared by Tukey test (p ≤ 0.05. The results showed a partial reduction of fungi after washing with ozonated water, but the same effect was not observed after drying. For coffee quality analysis, the longest times of exposure to the solubilized gas in the water produced some negative results in electrical conductivity and total and reducing sugars. However, the sensory quality of the beverage was maintained.

  11. Ozone exposure induces the activation of leaf senescence-related processes and morphological and growth changes in seedlings of Mediterranean tree species

    International Nuclear Information System (INIS)

    Ribas, Angela; Pen-tilde uelas, Josep; Elvira, Susana; Gimeno, Benjamin S.

    2005-01-01

    Four Mediterranean tree taxa, Quercus ilex subsp. ilex, Quercus ilex subsp. ballota, Olea europaea cv. vulgaris and Ceratonia siliqua, were exposed to different ozone (O 3 ) concentrations in open top chambers (OTCs) during 2 years. Three treatments were applied: charcoal-filtered air (CF), non-filtered air (NF) and non-filtered air plus 40 ppb v of O 3 (NF+). The photochemical maximal efficiency, Fv/Fm, decreased in NF+ plants during the second year of exposure, especially during the most stressful Mediterranean seasons (winter and summer). An increase of δ 13 C was found in three of the four studied species during the first year of exposure. This finding was only maintained in C. siliqua during the second year. Decreases in the chlorophyll content were detected during the first year of fumigations in all the species studied, but not during the second year. The NF+ treatment induced changes in foliar anatomical characteristics, especially in leaf mass per area (LMA) and spongy parenchyma thickness, which increased in some species. A reduction in N content and an increase in δ 15 N were found in all species during the second year when exposed in the NF+ OTCs, suggesting a change in their retranslocation pattern linked to an acceleration of leaf senescence, as also indicated by the above mentioned biochemical and anatomical foliar changes. The two Q. ilex subspecies were the most sensitive species since the changes in N concentration, δ 15 N, chlorophyll, leaf area, LMA and biomass occurred at ambient O 3 concentrations. However, C. siliqua was the most responsive species (29% biomass reduction) when exposed to the NF+ treatment, followed by the two Q. ilex subspecies (14-20%) and O. europaea (no significant reduction). Ozone resistance of the latter species was linked to some plant traits such as chlorophyll concentrations, or spongy parenchyma thickness. - Ozone induces species-specific leaf senescence-related processes and morphological and growth changes in

  12. Ozone exposure induces the activation of leaf senescence-related processes and morphological and growth changes in seedlings of Mediterranean tree species

    Energy Technology Data Exchange (ETDEWEB)

    Ribas, Angela [CSIC-CEAB-CREAF Ecophysiology Unit, CREAF-Center for Ecological Research and Forestry Applications, Edifici C, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)]. E-mail: a.ribas@creaf.uab.es; Pen-tilde uelas, Josep [CSIC-CEAB-CREAF Ecophysiology Unit, CREAF-Center for Ecological Research and Forestry Applications, Edifici C, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)]. E-mail: josep.penuelas@uab.es; Elvira, Susana [CIEMAT, Avd. Complutense 22, 28040 Madrid (Spain); Gimeno, Benjamin S. [CIEMAT, Avd. Complutense 22, 28040 Madrid (Spain)

    2005-03-01

    Four Mediterranean tree taxa, Quercus ilex subsp. ilex, Quercus ilex subsp. ballota, Olea europaea cv. vulgaris and Ceratonia siliqua, were exposed to different ozone (O{sub 3}) concentrations in open top chambers (OTCs) during 2 years. Three treatments were applied: charcoal-filtered air (CF), non-filtered air (NF) and non-filtered air plus 40 ppb{sub v} of O{sub 3} (NF+). The photochemical maximal efficiency, Fv/Fm, decreased in NF+ plants during the second year of exposure, especially during the most stressful Mediterranean seasons (winter and summer). An increase of {delta}{sup 13}C was found in three of the four studied species during the first year of exposure. This finding was only maintained in C. siliqua during the second year. Decreases in the chlorophyll content were detected during the first year of fumigations in all the species studied, but not during the second year. The NF+ treatment induced changes in foliar anatomical characteristics, especially in leaf mass per area (LMA) and spongy parenchyma thickness, which increased in some species. A reduction in N content and an increase in {delta}{sup 15}N were found in all species during the second year when exposed in the NF+ OTCs, suggesting a change in their retranslocation pattern linked to an acceleration of leaf senescence, as also indicated by the above mentioned biochemical and anatomical foliar changes. The two Q. ilex subspecies were the most sensitive species since the changes in N concentration, {delta}{sup 15}N, chlorophyll, leaf area, LMA and biomass occurred at ambient O{sub 3} concentrations. However, C. siliqua was the most responsive species (29% biomass reduction) when exposed to the NF+ treatment, followed by the two Q. ilex subspecies (14-20%) and O. europaea (no significant reduction). Ozone resistance of the latter species was linked to some plant traits such as chlorophyll concentrations, or spongy parenchyma thickness. - Ozone induces species-specific leaf senescence

  13. Physiological responses of Pinus sylvestris to changing carbon dioxide and ozone concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Holopainen, T [Kuopio Univ. (Finland). Dept. of Ecology and Environmental Science; Palomaeki, V [Joensuu Univ. (Finland). Faculty of Forestry; Helmisaari, H S [Finnish Forest Research Inst., Helsinki (Finland); and others

    1997-12-31

    The objective of this research is to study the effects of elevated ozone, carbon dioxide and their combination on ultrastructural, physiological and biochemical responses of Scots pine needles and how these effects are reflected to photosynthesis, carbohydrate and nutrient allocation and finally to shoot and root growth of trees. In addition the interactions of the studied trees and mycorrhizal fungi as well as insect herbivores are studied. The exposures have been running only for two growing periods and it seems necessary to continue the experiment over the third growing season in 1996. Since the analyses are partially incomplete, only preliminary conclusions are possible at the moment. The slightly increased shoot growth and needle width and increased amount of starch in chloroplasts point to the slight stimulating effect of elevated CO{sub 2} among the chamber treatments. Altogether the growth of the seedlings was best in the chamberless treatment indicating a negative chamber effect. The elevated ozone significantly increased the chlorotic mottling and overall yellowing of second year needles as well as caused increased density of chloroplast stroma and declined photosynthesis, all these responses being often related to ozone exposures. The ozone related responses appeared at both CO{sub 2} levels indicating no clear protection due to elevated CO{sub 2}. The ozone or carbon dioxide treatments were not able to significantly change nutrient concentrations, insect herbivory or carbon allocation among the secondary compounds of needles. A tendency of increased carbon allocation to fine roots due to ozone but not so clearly to CO{sub 2} was observed

  14. Physiological responses of Pinus sylvestris to changing carbon dioxide and ozone concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Holopainen, T. [Kuopio Univ. (Finland). Dept. of Ecology and Environmental Science; Palomaeki, V. [Joensuu Univ. (Finland). Faculty of Forestry; Helmisaari, H.S. [Finnish Forest Research Inst., Helsinki (Finland)] [and others

    1996-12-31

    The objective of this research is to study the effects of elevated ozone, carbon dioxide and their combination on ultrastructural, physiological and biochemical responses of Scots pine needles and how these effects are reflected to photosynthesis, carbohydrate and nutrient allocation and finally to shoot and root growth of trees. In addition the interactions of the studied trees and mycorrhizal fungi as well as insect herbivores are studied. The exposures have been running only for two growing periods and it seems necessary to continue the experiment over the third growing season in 1996. Since the analyses are partially incomplete, only preliminary conclusions are possible at the moment. The slightly increased shoot growth and needle width and increased amount of starch in chloroplasts point to the slight stimulating effect of elevated CO{sub 2} among the chamber treatments. Altogether the growth of the seedlings was best in the chamberless treatment indicating a negative chamber effect. The elevated ozone significantly increased the chlorotic mottling and overall yellowing of second year needles as well as caused increased density of chloroplast stroma and declined photosynthesis, all these responses being often related to ozone exposures. The ozone related responses appeared at both CO{sub 2} levels indicating no clear protection due to elevated CO{sub 2}. The ozone or carbon dioxide treatments were not able to significantly change nutrient concentrations, insect herbivory or carbon allocation among the secondary compounds of needles. A tendency of increased carbon allocation to fine roots due to ozone but not so clearly to CO{sub 2} was observed

  15. Long-term Measurements of Summer-time Ozone at the Walnut Grove Tower - Understanding Trends in the Boundary Layer

    Science.gov (United States)

    Mahmud, A.; Di, P.; Mims, D.; Avise, J.; DaMassa, J.; Kaduwela, A. P.

    2015-12-01

    The California Air Resources Board (CARB) has been monitoring boundary layer ozone at the Walnut Grove Tower (WGT) since 1996 for investigating regional transport and vertical profile. Walnut Grove is located between Sacramento and Stockton, CA in the Sacramento - San Joaquin Delta. Sampling inlets are positioned at 30-ft, 400-ft, 800-ft, 1200-ft and 1600-ft levels of the 2000-ft tower, which is one of the tallest monitoring towers in the Western US. Ozone, ambient temperature, wind speed, and wind direction are simultaneously measured at each level, and reported as hourly averages. The current study included analyses of available ozone and corresponding meteorological data for the months of June - September from 1996 - 2014 with objectives to: 1) explore trends and inter-annual variability of ozone, 2) examine any correlations between ozone and meteorological parameters, 3) understand interactions of ozone measured at various levels, and 4) assess how well a regulatory state-of-the-science air quality model such as the Community Multi-scale Air Quality Model (CMAQ) captures observation. Daily 1-hr maximum ozone has been consistently decreasing during the 1996 - 2014 period at a rate of ~1 ppb per year. This indicates that CARB's measures to control ambient ozone have been effective over the past years. Evolution of the vertical profile throughout the day shows that ozone is fairly homogeneously mixed between 1 - 5 pm, when mixing height typically reaches the maximum. Ozone at 30-ft shows the greatest variability because of its proximity to the ground and emissions sources - rises faster during morning hours (7 - 10 am) and declines more rapidly during evening hours (7 - 10 pm) compared to other levels. Air masses reaching the tower are predominantly southwesterly (247 - 257 deg.) at the bottom, and southwesterly to slightly northwesterly (254 - 302 deg.) at top levels. Daily 1-hr maximum ozone was negatively correlated with wind speed (i.e. ozone was high under

  16. Toxicological analysis of limonene reaction products using an in vitro exposure system

    Science.gov (United States)

    Anderson, Stacey E.; Khurshid, Shahana S.; Meade, B. Jean; Lukomska, Ewa; Wells, J.R.

    2015-01-01

    Epidemiological investigations suggest a link between exposure to indoor air chemicals and adverse health effects. Consumer products contain reactive chemicals which can form secondary pollutants which may contribute to these effects. The reaction of limonene and ozone is a well characterized example of this type of indoor air chemistry. The studies described here characterize an in vitro model using an epithelial cell line (A549) or differentiated epithelial tissue (MucilAir™). The model is used to investigate adverse effects following exposure to combinations of limonene and ozone. In A549 cells, exposure to both the parent compounds and reaction products resulted in alterations in inflammatory cytokine production. A one hour exposure to limonene + ozone resulted in decreased proliferation when compared to cells exposed to limonene alone. Repeated dose exposures of limonene or limonene + ozone were conducted on MucilAir™ tissue. No change in proliferation was observed but increases in cytokine production were observed for both the parent compounds and reaction products. Factors such as exposure duration, chemical concentration, and sampling time point were identified to influence result outcome. These findings suggest that exposure to reaction products may produce more severe effects compared to the parent compound. PMID:23220291

  17. Ozone Layer Protection

    Science.gov (United States)

    ... and Research Centers Contact Us Share Ozone Layer Protection The stratospheric ozone layer is Earth’s “sunscreen” – protecting ... GreenChill Partnership Responsible Appliance Disposal (RAD) Program Ozone Protection vs. Ozone Pollution This website addresses stratospheric ozone ...

  18. Quantification of ozone uptake at the stand level in a Pinus canariensis forest in Tenerife, Canary Islands: An approach based on sap flow measurements

    Energy Technology Data Exchange (ETDEWEB)

    Wieser, Gerhard [Division of Alpine Timberline Ecophysiology, Federal Research and Training Centre for Forests, Natural Hazards and Landscape, Rennweg 1, A-6020 Innsbruck (Austria)]. E-mail: gerhard.wieser@uibk.ac.at; Luis, Vanessa C. [Department of Plant Biology, Plant Physiology, University of La Laguna, Avda. Astrofisico Francisco Sanchez s/n, E-38207 La Laguna, Tenerife (Spain); Cuevas, Emilio [Izana Atmospheric Observatory, National Institute of Meteorology, La Marina, E-38071 Santa Cruz de Tenerife (Spain)

    2006-04-15

    Ozone uptake was studied in a pine forest in Tenerife, Canary Islands, an ecotone with strong seasonal changes in climate. Ambient ozone concentration showed a pronounced seasonal course with high concentrations during the dry and warm period and low concentrations during the wet and cold season. Ozone uptake by contrast showed no clear seasonal trend. This is because canopy conductance significantly decreased with soil water availability and vapour pressure deficit. Mean daily ozone uptake averaged 1.9 nmol m{sup -2} s{sup -1} during the wet and cold season, and 1.5 nmol m{sup -2} s{sup -1} during the warm and dry period. The corresponding daily mean ambient ozone concentrations were 42 and 51 nl l{sup -1}, respectively. Thus we conclude that in Mediterranean type forest ecosystems the flux based approach is more capable for risk assessment than an external, concentration based approach. - Sap flow measurements can be used for estimating ozone uptake at the stand level and for parameterisation of O{sub 3} uptake models.

  19. Foliar injury responses of eleven plant species to ozone/sulfur dioxide mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Tingey, D T; Reinert, R A; Dunning, J A; Heck, W W

    1973-01-01

    Eleven plant species were exposed to ozone and/or sulfur dioxide to determine if a mixture of the two gases enhanced foliar injury. Tobacco, radish, and alfalfa developed more injury that the additive injury of the single gases. In other species, such as cabbage, broccoli, and tomato, the foliar injury from mixed-gas exposures was additive or less than additive. Leaf injury from the ozone/sulfur dioxide mixture appeared as upper surface flecking, stipple, bifacial necrosis, and lower surface glazing and, in general, appeared similar to injury from oxidant or ozone. The concentrations of ozone and sulfur dioxide that caused plant injury were similar to those found in urban areas. These concentrations may result in yield losses to plants grown under field conditions.

  20. Global health and economic impacts of future ozone pollution

    International Nuclear Information System (INIS)

    Selin, N E; Nam, K M; Reilly, J M; Paltsev, S; Prinn, R G; Webster, M D; Wu, S

    2009-01-01

    We assess the human health and economic impacts of projected 2000-2050 changes in ozone pollution using the MIT Emissions Prediction and Policy Analysis - Health Effects (EPPA-HE) model, in combination with results from the GEOS-Chem global tropospheric chemistry model of climate and chemistry effects of projected future emissions. We use EPPA-HE to assess the human health damages (including mortality and morbidity) caused by ozone pollution, and quantify their economic impacts in sixteen world regions. We compare the costs of ozone pollution under scenarios with 2000 and 2050 ozone precursor and greenhouse gas emissions (using the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A1B scenario). We estimate that health costs due to global ozone pollution above pre-industrial levels by 2050 will be $580 billion (year 2000$) and that mortalities from acute exposure will exceed 2 million. We find that previous methodologies underestimate costs of air pollution by more than a third because they do not take into account the long-term, compounding effects of health costs. The economic effects of emissions changes far exceed the influence of climate alone.

  1. Climatology 2011: An MLS and Sonde Derived Ozone Climatology for Satellite Retrieval Algorithms

    Science.gov (United States)

    McPeters, Richard D.; Labow, Gordon J.

    2012-01-01

    The ozone climatology used as the a priori for the version 8 Solar Backscatter Ultraviolet (SBUV) retrieval algorithms has been updated. The Microwave Limb Sounder (MLS) instrument on Aura has excellent latitude coverage and measures ozone daily from the upper troposphere to the lower mesosphere. The new climatology consists of monthly average ozone profiles for ten degree latitude zones covering pressure altitudes from 0 to 65 km. The climatology was formed by combining data from Aura MLS (2004-2010) with data from balloon sondes (1988-2010). Ozone below 8 km (below 12 km at high latitudes) is based on balloons sondes, while ozone above 16 km (21 km at high latitudes) is based on MLS measurements. Sonde and MLS data are blended in the transition region. Ozone accuracy in the upper troposphere is greatly improved because of the near uniform coverage by Aura MLS, while the addition of a large number of balloon sonde measurements improves the accuracy in the lower troposphere, in the tropics and southern hemisphere in particular. The addition of MLS data also improves the accuracy of climatology in the upper stratosphere and lower mesosphere. The revised climatology has been used for the latest reprocessing of SBUV and TOMS satellite ozone data.

  2. Climate Change Impacts on Projections of Excess Mortality at 2030 using Spatially-Varying Ozone-Temperature Risk Surfaces

    Science.gov (United States)

    Wilson, Ander; Reich, Brian J.; Nolte, Christopher G.; Spero, Tanya L.; Hubbell, Bryan; Rappold, Ana G.

    2017-01-01

    We project the change in ozone-related mortality burden attributable to changes in climate between a historical (1995–2005) and near-future (2025–2035) time period while incorporating a nonlinear and synergistic effect of ozone and temperature on mortality. We simulate air quality from climate projections varying only biogenic emissions and holding anthropogenic emissions constant, thus attributing changes in ozone only to changes in climate and independent of changes in air pollutant emissions. We estimate nonlinear, spatially-varying, ozone-temperature risk surfaces for 94 US urban areas using observed data. Using the risk surfaces and climate projections we estimate daily mortality attributable to ozone exceeding 40 ppb (moderate level) and 75 ppb (US ozone NAAQS) for each time period. The average increases in city-specific median April-October ozone and temperature between time periods are 1.02 ppb and 1.94°F; however, the results varied by region. Increases in ozone due to climate change result in an increase in ozone-mortality burden. Mortality attributed to ozone exceeding 40 ppb increases by 7.7% (1.6%, 14.2%). Mortality attributed to ozone exceeding 75 ppb increases by 14.2% (1.6%, 28.9%). The absolute increase in excess ozone mortality is larger for changes in moderate ozone levels, reflecting the larger number of days with moderate ozone levels. PMID:27005744

  3. The Ozone Monitoring Instrument: overview of 14 years in space

    Science.gov (United States)

    Levelt, Pieternel F.; Joiner, Joanna; Tamminen, Johanna; Pepijn Veefkind, J.; Bhartia, Pawan K.; Stein Zweers, Deborah C.; Duncan, Bryan N.; Streets, David G.; Eskes, Henk; van der A, Ronald; McLinden, Chris; Fioletov, Vitali; Carn, Simon; de Laat, Jos; DeLand, Matthew; Marchenko, Sergey; McPeters, Richard; Ziemke, Jerald; Fu, Dejian; Liu, Xiong; Pickering, Kenneth; Apituley, Arnoud; González Abad, Gonzalo; Arola, Antti; Boersma, Folkert; Miller, Christopher Chan; Chance, Kelly; de Graaf, Martin; Hakkarainen, Janne; Hassinen, Seppo; Ialongo, Iolanda; Kleipool, Quintus; Krotkov, Nickolay; Li, Can; Lamsal, Lok; Newman, Paul; Nowlan, Caroline; Suleiman, Raid; Gijsbert Tilstra, Lieuwe; Torres, Omar; Wang, Huiqun; Wargan, Krzysztof

    2018-04-01

    This overview paper highlights the successes of the Ozone Monitoring Instrument (OMI) on board the Aura satellite spanning a period of nearly 14 years. Data from OMI has been used in a wide range of applications and research resulting in many new findings. Due to its unprecedented spatial resolution, in combination with daily global coverage, OMI plays a unique role in measuring trace gases important for the ozone layer, air quality, and climate change. With the operational very fast delivery (VFD; direct readout) and near real-time (NRT) availability of the data, OMI also plays an important role in the development of operational services in the atmospheric chemistry domain.

  4. Comparative study of ozonized olive oil and ozonized sunflower oil

    Directory of Open Access Journals (Sweden)

    Díaz Maritza F.

    2006-01-01

    Full Text Available In this study the ozonized olive and sunflower oils are chemical and microbiologically compared. These oils were introduced into a reactor with bubbling ozone gas in a water bath at room temperature until they were solidified. The peroxide, acidity and iodine values along with antimicrobial activity were determined. Ozonization effects on the fatty acid composition of these oils were analyzed using Gas-Liquid Chromatographic Technique. An increase in peroxidation and acidity values was observed in both oils but they were higher in ozonized sunflower oil. Iodine value was zero in ozonized olive oil whereas in ozonized sunflower was 8.8 g Iodine per 100 g. The antimicrobial activity was similar for both ozonized oils except for Minimum Bactericidal Concentrations of Pseudomona aeruginosa. Composition of fatty acids in both ozonized oils showed gradual decrease in unsaturated fatty acids (C18:1, C18:2 with gradual increase in ozone doses.

  5. Screening agrochemicals as potential protectants of plants against ozone phytotoxicity

    International Nuclear Information System (INIS)

    Saitanis, Costas J.; Lekkas, Dimitrios V.; Agathokleous, Evgenios; Flouri, Fotini

    2015-01-01

    We tested seven contemporary agrochemicals as potential plant protectants against ozone phytotoxicity. In nine experiments, Bel-W3 tobacco plants were experienced weekly exposures to a) 80 nmol mol −1 of ozone-enriched or ozone-free air in controlled environment chambers, b) an urban air polluted area, and c) an agricultural-remote area. Ozone caused severe leaf injury, reduced chlorophylls' and total carotenoids' content, and negatively affected photosynthesis and stomatal conductance. Penconazole, (35% ± 8) hexaconazole (28% ± 5) and kresoxim-methyl (28% ± 15) showed higher plants’ protection (expressed as percentage; mean ± s.e.) against ozone, although the latter exhibited a high variability. Azoxystrobin (21% ± 15) showed lower protection efficacy and Benomyl (15% ± 9) even lower. Trifloxystrobin (7% ± 11) did not protect the plants at all. Acibenzolar-S-methyl + metalaxyl-M (Bion MX) (−6% ± 17) exhibited the higher variability and contrasting results: in some experiments it showed some protection while in others it intensified the ozone injury by causing phytotoxic symptoms on leaves, even in control plants. - Highlights: • Penconazole and hexaconazole offered some protection to plants against ozone. • Bion MX fungicide caused phytotoxic symptoms to Bel-W3 tobacco plants. • Stomatal conductance was reduced in ozone-fumigated plants. - Seven agrochemicals were assessed as potential protectants against ozone phytotoxicity – triazoles fungicides were the most effective

  6. Antarctic ozone loss in 1989-2010: evidence for ozone recovery?

    Science.gov (United States)

    Kuttippurath, J.; Lefèvre, F.; Pommereau, J.-P.; Roscoe, H. K.; Goutail, F.; Pazmiño, A.; Shanklin, J. D.

    2012-04-01

    We present a detailed estimation of chemical ozone loss in the Antarctic polar vortex from 1989 to 2010. The analyses include ozone loss estimates for 12 Antarctic ground-based (GB) stations. All GB observations show minimum ozone in the late September-early October period. Among the stations, the lowest minimum ozone values are observed at South Pole and the highest at Dumont d'Urville. The ozone loss starts by mid-June at the vortex edge and then progresses towards the vortex core with time. The loss intensifies in August-September, peaks by the end of September-early October, and recovers thereafter. The average ozone loss in the Antarctic is revealed to be about 33-50% in 1989-1992 in agreement with the increase in halogens during this period, and then stayed at around 48% due to saturation of the loss. The ozone loss in the warmer winters (e.g. 2002, and 2004) is lower (37-46%) and in the colder winters (e.g. 2003, and 2006) is higher (52-55%). Because of small inter-annual variability, the correlation between ozone loss and the volume of polar stratospheric clouds yields ~0.51. The GB ozone and ozone loss values are in good agreement with those found from the space-based observations of the Total Ozone Mapping Spectrometer/Ozone Monitoring Instrument (TOMS/OMI), the Global Ozone Monitoring Experiment (GOME), the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY), and the Aura Microwave Limb Sounder (MLS), where the differences are within ±5% and are mostly within the error bars of the measurements. The piece-wise linear trends computed from the September-November vortex average GB and TOMS/OMI ozone show about -4 to -5.6 DU (Dobson Unit) yr-1 in 1989-1996 and about +1 DU yr-1 in 1997-2010. The trend during the former period is significant at 95% confidence intervals, but the trend in 1997-2010 is significant only at 85% confidence intervals. Our analyses suggest a period of about 9-10 yr to get the first detectable ozone

  7. Dynamic interactions between hydrogeological and exposure parameters in daily dose prediction under uncertainty and temporal variability

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Vikas, E-mail: vikas.kumar@urv.cat [Department of Chemical Engineering, Rovira i Virgili University, Tarragona 43007 (Spain); Barros, Felipe P.J. de [Sonny Astani Department of Civil and Environmental Engineering, University of Southern California, Los Angeles 90089, CA (United States); Schuhmacher, Marta [Department of Chemical Engineering, Rovira i Virgili University, Tarragona 43007 (Spain); Fernàndez-Garcia, Daniel; Sanchez-Vila, Xavier [Hydrogeology Group, Department of Geotechnical Engineering and Geosciences, University Politècnica de Catalunya-BarcelonaTech, Barcelona 08034 (Spain)

    2013-12-15

    Highlights: • Dynamic parametric interaction in daily dose prediction under uncertainty. • Importance of temporal dynamics associated with the dose. • Different dose experienced by different population cohorts as a function of time. • Relevance of uncertainty reduction in the input parameters shows temporal dynamism. -- Abstract: We study the time dependent interaction between hydrogeological and exposure parameters in daily dose predictions due to exposure of humans to groundwater contamination. Dose predictions are treated stochastically to account for an incomplete hydrogeological and geochemical field characterization, and an incomplete knowledge of the physiological response. We used a nested Monte Carlo framework to account for uncertainty and variability arising from both hydrogeological and exposure variables. Our interest is in the temporal dynamics of the total dose and their effects on parametric uncertainty reduction. We illustrate the approach to a HCH (lindane) pollution problem at the Ebro River, Spain. The temporal distribution of lindane in the river water can have a strong impact in the evaluation of risk. The total dose displays a non-linear effect on different population cohorts, indicating the need to account for population variability. We then expand the concept of Comparative Information Yield Curves developed earlier (see de Barros et al. [29]) to evaluate parametric uncertainty reduction under temporally variable exposure dose. Results show that the importance of parametric uncertainty reduction varies according to the temporal dynamics of the lindane plume. The approach could be used for any chemical to aid decision makers to better allocate resources towards reducing uncertainty.

  8. On the link between martian total ozone and potential vorticity

    Science.gov (United States)

    Holmes, James A.; Lewis, Stephen R.; Patel, Manish R.

    2017-01-01

    We demonstrate for the first time that total ozone in the martian atmosphere is highly correlated with the dynamical tracer, potential vorticity, under certain conditions. The degree of correlation is investigated using a Mars global circulation model including a photochemical model. Potential vorticity is the quantity of choice to explore the dynamical nature of polar vortices because it contains information on winds and temperature in a single scalar variable. The correlation is found to display a distinct seasonal variation, with a strong positive correlation in both northern and southern winter at poleward latitudes in the northern and southern hemisphere respectively. The identified strong correlation implies variations in polar total ozone during winter are predominantly controlled by dynamical processes in these spatio-temporal regions. The weak correlation in northern and southern summer is due to the dominance of photochemical reactions resulting from extended exposure to sunlight. The total ozone/potential vorticity correlation is slightly weaker in southern winter due to topographical variations and the preference for ozone to accumulate in Hellas basin. In northern winter, total ozone can be used to track the polar vortex edge. The ozone/potential vorticity ratio is calculated for both northern and southern winter on Mars for the first time. Using the strong correlation in total ozone and potential vorticity in northern winter inside the polar vortex, it is shown that potential vorticity can be used as a proxy to deduce the distribution of total ozone where satellites cannot observe for the majority of northern winter. Where total ozone observations are available on the fringes of northern winter at poleward latitudes, the strong relationship of total ozone and potential vorticity implies that total ozone anomalies in the surf zone of the northern polar vortex can potentially be used to determine the origin of potential vorticity filaments.

  9. The antioxidant EDU and Raphanus sativus L. - a new approach to biological indication of ozone?; Das Antioxidant EDU und Raphanus sativus L. - neue Moeglichkeiten der Bioindikation von Ozon?

    Energy Technology Data Exchange (ETDEWEB)

    Kostka-Rick, R; Manning, W J

    1993-12-31

    Studies on the effects of ozone on plants repeatedly suggested to use anti-oxidant agent-like ethylene diurea (EDU) as control treatment for exposure systems like open-top chambers. Radish (`Cherry Belle`) was exposed to ozone (135-225 {mu}g m{sup -3}, 7.5 h d{sup -1}, 7 d) in a controlled way in green-house tests run during three different developmental stages. Some plants received pretreatment with EDU (150 mg l{sup -1}). Up to 26% of the leaf surface was injured by ozone exposure in untreated plants; EDU-treated plants and control plants grown in filtered ais showed a maximum of 2% of leaf injury. The growth of the storage organ (hypocotyl) was significantly depressed by ozone exposure (without EDU) but compensatory processes largely redressed this loss after the exposure period. EDU caused some minor leaf injury and a nonsignificant stimulation of shoot growth. (orig.) [Deutsch] In O{sub 3}-Wirkungsuntersuchungen mit Pflanzen wurde wiederholt der Einsatz antioxidanter Wirkstoffe wie Ethylendiurea (EDU) als Kontrollbehandlung alternativ zu Expositionssystemen wie z.B. Open-Top-Kammern vorgeschlagen. Waehrend drei verschiedener Entwicklungsstadien wurden Radies (Sorte `Cherry Belle`) in einem Gewaechshausversuch kontrolliert mit O{sub 3} belastet (135-225 {mu}g m{sup -3}, 7.5 h d{sup -1}, 7 d), nachdem ein Teil der Pflanzen mit EDU behandelt worden war (150 mg l{sup -1}). Bei unbehandelten Pflanzen wurden bis zu 26% der Blattflaeche durch die O{sub 3}-Exposition geschaedigt; EDU-behandelte Pflanzen und Kontrollpflanzen in gefilterter Luft zeigten maximal 2% Blattschaedigung. Das Wachstum des Speicherorgans (Hypokotyl) war durch die O{sub 3}-Belastung (ohne EDU) signifikant vermindert, kompensatorische Prozesse glichen diesen Verlust nach der Belastungsphase jedoch weitgehend aus. EDU selbst loeste leichte Blattschaedigungen aus und bewirkte eine nicht-signifikante Stimulation des Sprosswachstums. (orig.)

  10. The antioxidant EDU and Raphanus sativus L. - a new approach to biological indication of ozone?; Das Antioxidant EDU und Raphanus sativus L. - neue Moeglichkeiten der Bioindikation von Ozon?

    Energy Technology Data Exchange (ETDEWEB)

    Kostka-Rick, R.; Manning, W.J.

    1992-12-31

    Studies on the effects of ozone on plants repeatedly suggested to use anti-oxidant agent-like ethylene diurea (EDU) as control treatment for exposure systems like open-top chambers. Radish (`Cherry Belle`) was exposed to ozone (135-225 {mu}g m{sup -3}, 7.5 h d{sup -1}, 7 d) in a controlled way in green-house tests run during three different developmental stages. Some plants received pretreatment with EDU (150 mg l{sup -1}). Up to 26% of the leaf surface was injured by ozone exposure in untreated plants; EDU-treated plants and control plants grown in filtered ais showed a maximum of 2% of leaf injury. The growth of the storage organ (hypocotyl) was significantly depressed by ozone exposure (without EDU) but compensatory processes largely redressed this loss after the exposure period. EDU caused some minor leaf injury and a nonsignificant stimulation of shoot growth. (orig.) [Deutsch] In O{sub 3}-Wirkungsuntersuchungen mit Pflanzen wurde wiederholt der Einsatz antioxidanter Wirkstoffe wie Ethylendiurea (EDU) als Kontrollbehandlung alternativ zu Expositionssystemen wie z.B. Open-Top-Kammern vorgeschlagen. Waehrend drei verschiedener Entwicklungsstadien wurden Radies (Sorte `Cherry Belle`) in einem Gewaechshausversuch kontrolliert mit O{sub 3} belastet (135-225 {mu}g m{sup -3}, 7.5 h d{sup -1}, 7 d), nachdem ein Teil der Pflanzen mit EDU behandelt worden war (150 mg l{sup -1}). Bei unbehandelten Pflanzen wurden bis zu 26% der Blattflaeche durch die O{sub 3}-Exposition geschaedigt; EDU-behandelte Pflanzen und Kontrollpflanzen in gefilterter Luft zeigten maximal 2% Blattschaedigung. Das Wachstum des Speicherorgans (Hypokotyl) war durch die O{sub 3}-Belastung (ohne EDU) signifikant vermindert, kompensatorische Prozesse glichen diesen Verlust nach der Belastungsphase jedoch weitgehend aus. EDU selbst loeste leichte Blattschaedigungen aus und bewirkte eine nicht-signifikante Stimulation des Sprosswachstums. (orig.)

  11. Ozone acts alone and synergistically with ionizing radiation to induce in vitro neoplastic transformation

    Energy Technology Data Exchange (ETDEWEB)

    Borek, C; Zaider, M; Ong, A; Mason, H; Witz, G

    1986-09-01

    Ozone, a major chemical oxidant in the atmosphere, is an environmental air pollutant whose ability to act as a direct carcinogen is unclear. Using in vitro transformation, a technique which permits the study of oncogenesis in the absence of host specific effects, it is reported for the first time that ozone (5 p.p.m. for 5 min) induces neoplastic transformation in vitro in both primary hamster embryo cells and mouse fibroblast cultures (C3H/10-1/2). Exposure of the hamster and mouse cells to ozone also results in enhanced levels of free radical-mediated lipid peroxidation products. The carcinogenic interaction between ozone and ionizing radiation is also reported. Exposure of the cells to 3 or 4 Gy of ..gamma..-rays, 2 h prior to O/sub 3/ treatment, results in markedly enhanced rates of transformation, statistically consistent with a synergistic interaction between the agents. The results demonstrate that O/sub 3/ acts as a direct carcinogen and co-carcinogen on susceptible cells, therefore having important consequences for public health.

  12. Acid mist and ozone effects on the leaf chemistry of two western conifer species

    Science.gov (United States)

    Westman, Walter E.; Temple, Patrick J.

    1989-01-01

    The effects of ozone and acid-mist exposures on the leaf chemistry of Jeffrey pine and giant sequoia seedlings grown in filtered-air greenhouses were investigated. Acid-mist treatments (pH 4.1, 3.4, 2.7, or 2.0) were administered for 3 h, and ozone exposures (0, 0.10, and 0.20 microliter/liter), which followed acid-mist treatments, for 4 h, each for three days a week for six to nine weeks. It was found that seedlings were more susceptible to acid-mist and acid mist/ozone combinations, than to ozone alone. Acid mist treatment resulted in higher levels of nitrogen and sulfur (both present in acid mist) as well as Na. Leaves of giant sequoia exhibited increased K and decreased Mn, while Jeffrey pine showed increases in Fe and Mn. In sequoia leaves, concentrations of Ca, Mg, and Ba decreased. Acid treatment also reduced chlorophyll b concentrations in both conifer species. Extensive changes induced by acid mist are consistent with earlier observations of changes in spectral reflectance of conifer seedlings observed after three weeks of fumigation.

  13. Global environment and radiation exposure

    International Nuclear Information System (INIS)

    Okamoto, Kazuto

    1991-01-01

    The present status of investigation of acid rain, stratospheric ozone depletion and greenhouse effect and their relations to radiation exposure are reported. Soil acidification increases transfer rates of radioactivities to plants which increases the population dose. There are two types of ozone depletion, conventional type and ozone hole type and the latter is much more serious than the former. In the greenhouse effect, although there are large uncertainties both in theoretical and observational sides, present predictions about the global warming will not be very far from reality. Environmental effects are wide-ranging and serious. Radon and thoron exhalation rates are affected by the global warming. The influence of the greenhouse effect on ozone depletion is to suppress depletion for conventional type and enhance depletion for ozone hole type. (author) 65 refs

  14. Ozone modeling within plasmas for ozone sensor applications

    OpenAIRE

    Arshak, Khalil; Forde, Edward; Guiney, Ivor

    2007-01-01

    peer-reviewed Ozone (03) is potentially hazardous to human health and accurate prediction and measurement of this gas is essential in addressing its associated health risks. This paper presents theory to predict the levels of ozone concentration emittedfrom a dielectric barrier discharge (DBD) plasma for ozone sensing applications. This is done by postulating the kinetic model for ozone generation, with a DBD plasma at atmospheric pressure in air, in the form of a set of rate equations....

  15. Interactions involving ozone, Botrytis cinerea, and B. squamosa on onion leaves

    Energy Technology Data Exchange (ETDEWEB)

    Rist, D.L.

    1983-01-01

    Interactions involving Botrytis cinerea Pers., B. squamosa Walker, and ozone on onion (alium cepae L.) were investigated. Initially, threshold dosages of ozone required to predispose onion leaves to greater infection by B. cinerea and B. squamosa were determined under controlled conditions in an ozone-exposure chamber. Subsequent experiments supported the hypothesis that nutrients leaking out of ozone-injured cells stimulated lesion production by B. cinerea. The electrical conductivity of, and carbohydrate concentration in, dew collected from leaves of onion plants which had been exposed to ozone were greater than the electrical conductivity of, and carbohydrate concentration in, dew collected from leaves of other, non-exposed onion plants. When conidia of B. cinerea were suspended in dew collected from leaves of plants which had been exposed to ozone and the resulting suspension atomized onto leaves of non-exposed plants, more lesions were induced than on leaves of other non-exposed plants inoculated with conidia suspended in dew collected from plants which had not been exposed to ozone. EDU protected onion leaves from ozone-induced predisposition to these fungi under controlled conditions. Experiments designed to detect interaction between B. cinerea and B. squamosa in onion leaf blighting indicated that such interaction did not occur. Leaves were blighted rapidly when inoculated with B. squamosa whether B. cinerea was present or absent.

  16. Wintertime pollution level, size distribution and personal daily exposure to particulate matters in the northern and southern rural Chinese homes and variation in different household fuels.

    Science.gov (United States)

    Du, Wei; Shen, Guofeng; Chen, Yuanchen; Zhuo, Shaojie; Xu, Yang; Li, Xinyue; Pan, Xuelian; Cheng, Hefa; Wang, Xilong; Tao, Shu

    2017-12-01

    This study investigated and compared wintertime air pollution and personal exposure in the rural northern and southern Chinese homes. Daily indoor and outdoor particle samples were simultaneously collected by using stationary samplers, and personal exposure was directly measured using portable carried samplers. The daily average concentrations of indoor and outdoor PM 2.5 were 521 ± 234 and 365 ± 185 μg/m 3 in the northern village, that were about 2.3-2.7 times of 188 ± 104 and 150 ± 29 μg/m 3 in indoor and outdoor air in the southern villages. Particle size distribution was similar between indoor and outdoor air, and had relatively smaller difference between the two sites, relative to the particle mass concentration difference. PM 2.5 contributed to ∼80% of the TSP mass, and in PM 2.5 , near 90% were PM 1.0 . In homes using electricity in the southern villages, outdoor air pollution could explain 70-80% of the variation in indoor air pollution. The daily exposure to PM 2.5 measured using personal carried samplers were 451 ± 301 μg/m 3 in the northern villages with traditional solid fuels used for daily cooking and heating, and in the southern villages without heating, the exposure to PM 2.5 were 184 ± 83 and 166 ± 45 μg/m 3 , respectively, for the population using wood and electricity for daily cooking. Time-weighted daily average exposure estimated from area concentration and time spent indoor and outdoor was generally correlated the directly measured exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Evaluation of the stomatal conductance formulation in the EMEP ozone deposition model for Picea abies

    Science.gov (United States)

    Wieser, G.; Emberson, L. D.

    It is widely acknowledged that the possible impacts of ozone on forest trees are more closely related to ozone flux through the stomata than to external ozone exposure. However, the application of the flux approach on a European scale requires the availability of appropriate models, such as the European Monitoring and Evaluation Programme (EMEP) ozone deposition model, for estimating ozone flux and cumulative ozone uptake. Within this model stomatal conductance is the key variable, since it determines the amount of ozone absorbed by the leaves. This paper describes the suitability of the existing EMEP ozone deposition model parameterisation and formulation to represent stomatal behaviour determined from field measurements on adult Norway spruce ( Picea abies (L.) Karst.) trees in the Central European Alps. Parameters affecting maximum stomatal conductance (e.g. seasonal phenology, needle position, needle age, nutrient deficiency and ozone itself) and stomatal response functions to temperature, irradiance, vapour pressure deficit, and soil water content are investigated. Finally, current limitations and possible alterations of the EMEP model will be discussed with respect to spatial scales of available input data for future flux modelling.

  18. Unprotected daily sun exposure is differently associated with central adiposity and beta-cell dysfunction by gender: The Korean national health and nutrition examination survey (KNHANES) V

    Energy Technology Data Exchange (ETDEWEB)

    Ohn, Jung Hun [Division of Endocrinology and Metabolism, Department of Internal Medicine, Hallym University College of Medicine, Chuncheon (Korea, Republic of); Kwon, In Ho [Department of Dermatology, Hallym University Dongtan Sacred Heart Hospital, Hwaseong (Korea, Republic of); Park, Juri; Ryu, Ohk Hyun; Lee, Seong Jin; Kim, Doo-Man; Ihm, Sung-Hee; Choi, Moon-Gi; Yoo, Hyung Joon [Division of Endocrinology and Metabolism, Department of Internal Medicine, Hallym University College of Medicine, Chuncheon (Korea, Republic of); Hong, Eun-Gyoung, E-mail: hegletter@hallym.or.kr [Division of Endocrinology and Metabolism, Department of Internal Medicine, Hallym University College of Medicine, Chuncheon (Korea, Republic of)

    2014-08-15

    Background: Ultraviolet irradiation by sun exposure has been associated with both harms and benefits to metabolic health. Objective: The objective of this study was to determine whether unprotected daily sun exposure is associated with the prevalence of diabetes and explore the underlying mechanism. Methods: We analyzed the Korean National Health and Nutrition Survey V from 2010 to 2011. Participants 19–60 years of age were asked about the average amount of time they had been exposed to direct sunlight per day since the age of 19. We categorized participants into three groups with different levels of lifetime daily sun exposure and explored the association of sun exposure with the prevalence of diabetes. Results: The risk of diabetes was higher in subjects with more than 5 h of unprotected sun exposure per day, with an odds ratio of 2.39 (95% CI 1.75–3.25), compared to those with less than 2 h of sun exposure, and the association remained significant after adjusting for diabetes risk factors. Long-term sun exposure was associated with increased central obesity and the possibility of an increase in visceral adiposity, especially among women, and with decrease in beta cell function and peripheral adiposity or percent body fat in men. Conclusions: Our study provides a cutoff for upper limit of sun exposure and suggests unprotected daily sun exposure for more than 5 h should be avoided to prevent diabetes. Increased central adiposity and decreased beta cell function were observed in women and men, respectively, who had long-term unprotected daily sun exposure. - Highlights: • Sun exposure for more than 5 h per day is associated with diabetes risk. • Insulin resistance associated with visceral adiposity may play a role in women. • Insulin secretory defect may explain diabetes risk in men.

  19. Unprotected daily sun exposure is differently associated with central adiposity and beta-cell dysfunction by gender: The Korean national health and nutrition examination survey (KNHANES) V

    International Nuclear Information System (INIS)

    Ohn, Jung Hun; Kwon, In Ho; Park, Juri; Ryu, Ohk Hyun; Lee, Seong Jin; Kim, Doo-Man; Ihm, Sung-Hee; Choi, Moon-Gi; Yoo, Hyung Joon; Hong, Eun-Gyoung

    2014-01-01

    Background: Ultraviolet irradiation by sun exposure has been associated with both harms and benefits to metabolic health. Objective: The objective of this study was to determine whether unprotected daily sun exposure is associated with the prevalence of diabetes and explore the underlying mechanism. Methods: We analyzed the Korean National Health and Nutrition Survey V from 2010 to 2011. Participants 19–60 years of age were asked about the average amount of time they had been exposed to direct sunlight per day since the age of 19. We categorized participants into three groups with different levels of lifetime daily sun exposure and explored the association of sun exposure with the prevalence of diabetes. Results: The risk of diabetes was higher in subjects with more than 5 h of unprotected sun exposure per day, with an odds ratio of 2.39 (95% CI 1.75–3.25), compared to those with less than 2 h of sun exposure, and the association remained significant after adjusting for diabetes risk factors. Long-term sun exposure was associated with increased central obesity and the possibility of an increase in visceral adiposity, especially among women, and with decrease in beta cell function and peripheral adiposity or percent body fat in men. Conclusions: Our study provides a cutoff for upper limit of sun exposure and suggests unprotected daily sun exposure for more than 5 h should be avoided to prevent diabetes. Increased central adiposity and decreased beta cell function were observed in women and men, respectively, who had long-term unprotected daily sun exposure. - Highlights: • Sun exposure for more than 5 h per day is associated with diabetes risk. • Insulin resistance associated with visceral adiposity may play a role in women. • Insulin secretory defect may explain diabetes risk in men

  20. Pulmonary sensitivity to ozone exposure in sedentary versus chronically trained, female rats

    Data.gov (United States)

    U.S. Environmental Protection Agency — Pulmonary effects to ozone with rats that have chronically exercised or have been continuously sedentary. Also includes body composition of both groups throughout...

  1. On-line monitoring of ozonation through estimation of Ct value and AOC formation with UV/Vis spectrometry

    NARCIS (Netherlands)

    Ross, P.S.; Van der Helm, A.W.C.; Van den Broeke, J.; Rietveld, L.C.

    2012-01-01

    The application of ozone in water treatment serves many purposes, such as disinfection, degradation of organic micro-pollutants and oxidation of taste, odour and colour producing compounds. A commonly used method to determine the disinfection capacity of ozonation is calculating the exposure of

  2. Effect of fiber material on ozone removal and carbonyl production from carpets

    Science.gov (United States)

    Abbass, Omed A.; Sailor, David J.; Gall, Elliott T.

    2017-01-01

    Indoor air quality is affected by indoor materials such as carpets that may act as sources and/or sinks of gas-phase air pollutants. Heterogeneous reactions of ozone with carpets may result in potentially harmful products. In this study, indoor residential carpets of varying fiber types were tested to evaluate their ability to remove ozone, and to assess their role in the production of carbonyls when exposed to elevated levels of ozone. Tests were conducted with six types of new unused carpets. Two sets of experiments were conducted, the first measured ozone removal and ozone deposition velocities, and the second measured primary carbonyl production and secondary production as a result of exposure to ozone. The tests were conducted using glass chambers with volume of 52 L each. Air exchange rates for all tests were 3 h-1. The ozone removal tests show that, for the conditions tested, the polyester carpet sample had the lowest ozone removal (40%), while wool carpet had the greatest ozone removal (65%). Most carpet samples showed higher secondary than primary carbonyl emissions, with carpets containing polypropylene fibers being a notable exception. Carpets with polyester fibers had both the highest primary and secondary emissions of formaldehyde among all samples tested. While it is difficult to make blanket conclusions about the relative air quality merits of various carpet fiber options, it is clear that ozone removal percentages and emissions of volatile organic compounds can vary drastically as a function of fiber type.

  3. Tree age dependence and within-canopy variation of leaf gas exchange and antioxidative defence in Fagus sylvatica under experimental free-air ozone exposure

    International Nuclear Information System (INIS)

    Herbinger, K.; Then, Ch.; Loew, M.; Haberer, K.; Alexous, M.; Koch, N.; Remele, K.; Heerdt, C.; Grill, D.; Rennenberg, H.; Haeberle, K.-H.; Matyssek, R.; Tausz, M.; Wieser, G.

    2005-01-01

    We characterized leaf gas exchange and antioxidative defence of two-year-old seedlings and 60-year-old trees of Fagus sylvatica exposed to ambient (1xO 3 ) or two-fold ambient (2xO 3 ) O 3 concentrations (maximum of 150 ppb) in a free-air canopy exposure system throughout the growing season. Decline in photosynthesis from sun-exposed to shaded conditions was more pronounced in adult than juvenile trees. Seedling leaves and leaves in the sun-exposed canopy had higher stomatal conductance and higher internal CO 2 concentrations relative to leaves of adult trees and leaves in shaded conditions. There was a weak overall depression of photosynthesis in the 2xO 3 variants across age classes and canopy positions. Pigment and tocopherol concentrations of leaves were significantly affected by canopy position and tree age, whereas differences between 1xO 3 and 2xO 3 regimes were not observed. Glutathione concentrations were significantly increased under 2xO 3 across both age classes and canopy levels. Seedlings differed from adult trees in relevant physiological and biochemical traits in ozone response. The water-soluble antioxidative systems responded most sensitively to 2xO 3 without regard of tree age or canopy position. - Ozone effects on leaf gas exchange and antioxidative systems of beech across tree age and canopy level were investigated in a free air exposure system

  4. Global health benefits of mitigating ozone pollution with methane emission controls.

    Science.gov (United States)

    West, J Jason; Fiore, Arlene M; Horowitz, Larry W; Mauzerall, Denise L

    2006-03-14

    Methane (CH(4)) contributes to the growing global background concentration of tropospheric ozone (O(3)), an air pollutant associated with premature mortality. Methane and ozone are also important greenhouse gases. Reducing methane emissions therefore decreases surface ozone everywhere while slowing climate warming, but although methane mitigation has been considered to address climate change, it has not for air quality. Here we show that global decreases in surface ozone concentrations, due to methane mitigation, result in substantial and widespread decreases in premature human mortality. Reducing global anthropogenic methane emissions by 20% beginning in 2010 would decrease the average daily maximum 8-h surface ozone by approximately 1 part per billion by volume globally. By using epidemiologic ozone-mortality relationships, this ozone reduction is estimated to prevent approximately 30,000 premature all-cause mortalities globally in 2030, and approximately 370,000 between 2010 and 2030. If only cardiovascular and respiratory mortalities are considered, approximately 17,000 global mortalities can be avoided in 2030. The marginal cost-effectiveness of this 20% methane reduction is estimated to be approximately 420,000 US dollars per avoided mortality. If avoided mortalities are valued at 1 US dollars million each, the benefit is approximately 240 US dollars per tone of CH(4) ( approximately 12 US dollars per tone of CO(2) equivalent), which exceeds the marginal cost of the methane reduction. These estimated air pollution ancillary benefits of climate-motivated methane emission reductions are comparable with those estimated previously for CO(2). Methane mitigation offers a unique opportunity to improve air quality globally and can be a cost-effective component of international ozone management, bringing multiple benefits for air quality, public health, agriculture, climate, and energy.

  5. Solar photo-ozonation: A novel treatment method for the degradation of water pollutants

    International Nuclear Information System (INIS)

    Chávez, Ana M.; Rey, Ana; Beltrán, Fernando J.; Álvarez, Pedro M.

    2016-01-01

    Highlights: • Aqueous ozone decomposition is accelerated by solar radiation. • Hydrogen peroxide is identifies as a main intermediate of decomposition of aqueous ozone under solar irradiation. • Solar photo-ozonation leads to higher Rct ratios than single ozonation. • Solar photo-ozonation is a promising AOP for the degradation of water pollutants. - Abstract: The decomposition of aqueous ozone by UV–vis radiation has been investigated with focus on the impact of ozone photolysis on the degradation of water pollutants during solar ozonation processes. The apparent first-order rate constants of the decomposition of ozone (k_o_b_s) have been determined at various pHs in the 4–9 range using radiation of different wavelengths in the UV–vis range. It was found that UVA–visible radiation (λ > 320 nm) highly enhanced ozone decomposition, especially at pH 4, for which k_o_b_s was three-folded with respect to the process in the absence of radiation. Hydrogen peroxide was identified as a main intermediate of ozone photo-decomposition at pH 4. Experiments of degradation of oxalic acid by ozone showed that solar irradiation brings about an increase in the hydroxyl radical to ozone exposures ratio (R_c_t). Finally, photo-ozonation (λ > 300 nm) was shown advantageous over single ozonation in the mineralization of a selection of emerging contaminants (metoprolol, ibuprofen, N,N-diethyl-meta-toluamide and clofibric acid) in both ultrapure water and a synthetic secondary effluent. Thus, TOC removal in 2-h treatments increased from 10 to 25% in the absence of radiation to about 50% in the presence of radiation.

  6. Solar photo-ozonation: A novel treatment method for the degradation of water pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Chávez, Ana M.; Rey, Ana; Beltrán, Fernando J.; Álvarez, Pedro M., E-mail: pmalvare@unex.es

    2016-11-05

    Highlights: • Aqueous ozone decomposition is accelerated by solar radiation. • Hydrogen peroxide is identifies as a main intermediate of decomposition of aqueous ozone under solar irradiation. • Solar photo-ozonation leads to higher Rct ratios than single ozonation. • Solar photo-ozonation is a promising AOP for the degradation of water pollutants. - Abstract: The decomposition of aqueous ozone by UV–vis radiation has been investigated with focus on the impact of ozone photolysis on the degradation of water pollutants during solar ozonation processes. The apparent first-order rate constants of the decomposition of ozone (k{sub obs}) have been determined at various pHs in the 4–9 range using radiation of different wavelengths in the UV–vis range. It was found that UVA–visible radiation (λ > 320 nm) highly enhanced ozone decomposition, especially at pH 4, for which k{sub obs} was three-folded with respect to the process in the absence of radiation. Hydrogen peroxide was identified as a main intermediate of ozone photo-decomposition at pH 4. Experiments of degradation of oxalic acid by ozone showed that solar irradiation brings about an increase in the hydroxyl radical to ozone exposures ratio (R{sub ct}). Finally, photo-ozonation (λ > 300 nm) was shown advantageous over single ozonation in the mineralization of a selection of emerging contaminants (metoprolol, ibuprofen, N,N-diethyl-meta-toluamide and clofibric acid) in both ultrapure water and a synthetic secondary effluent. Thus, TOC removal in 2-h treatments increased from 10 to 25% in the absence of radiation to about 50% in the presence of radiation.

  7. Enhancement of bromate formation by pH depression during ozonation of bromide-containing water in the presence of hydroxylamine.

    Science.gov (United States)

    Yang, Jingxin; Li, Ji; Dong, Wenyi; Ma, Jun; Yang, Yi; Li, Jiayin; Yang, Zhichao; Zhang, Xiaolei; Gu, Jia; Xie, Wanying; Cang, Yan

    2017-02-01

    This work investigated the fate of bromate formation during ozonation in the presence of hydroxylamine (HA). Results indicated that pH depression, as a commonly feasible control strategy for bromate formation during ozonation, unexpectedly enhanced the bromate formation during ozonation in the presence of HA. A dramatically high level of bromate was observed at acidic pH in the ozone/HA process. The scavenging experiments demonstrated the essential role of OH produced in the reaction of ozone with HA in bromate formation. In the process, OH mainly oxidizes bromide to Br, which is further oxidized by ozone and eventually converts to bromate. Further investigations suggested that the unexpected enhancement on bromate formation by pH depression can be mainly ascribed to the pH-dependent ozone decay, OH exposures and formation rate of Br. As pH decreased from 7 to 5, the reduced OH scavenging capacity of HA led to higher OH exposures, which contributed to the enhancement of bromate formation. As pH decreased from 5 to 3, the enhanced formation rate of Br largely augmented the formation of bromate. In addition, the ozone decay slowed down by pH depression provided more available ozone for the oxidation of the formed Br to bromate. The enhanced effect of pH depression on bromate formation was still observed in the real water samples in the ozone/HA process. Accordingly, pH depression might be avoided to control the bromate formation during ozonation in the presence of HA. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Protective effect of Mn(III)-desferrioxamine B upon oxidative stress caused by ozone and acid rain in the Brazilian soybean cultivar Glycine max "Sambaiba".

    Science.gov (United States)

    Esposito, Jéssica Bordotti Nobre; Esposito, Breno Pannia; Azevedo, Ricardo Antunes; Cruz, Luciano Soares; da Silva, Luzimar Campos; de Souza, Silvia Ribeiro

    2015-04-01

    This study aimed to investigate the effects of the Mn complex (Mn(III)-desferrioxamine B (MnDFB)) on oxidative stress in the Brazilian soybean cultivar Glycine max "Sambaiba" following exposure to ozone and acid rain. We determined the suitable dose of MnDFB to apply to G. max seedlings using a dose-response curve. The highest superoxide dismutase (SOD) activity and Mn content in leaves were found upon the application of 8 μM MnDFB. Thus, G. max seedlings pretreated with 8 μM MnDFB were individually exposed to ozone and acid rain simulated. Pretreatment with MnDFB reduced lipid peroxidation upon ozone exposure and increased SOD activity in leaves; it did not alter the metal content in any part of the plant. Conversely, following acid rain exposure, neither the metal content in leaves nor SOD enzyme activity were directly affected by MnDFB, unlike pH. Our findings demonstrated that exogenous MnDFB application before ozone exposure may modulate the MnSOD, Cu/ZnSOD, and FeSOD activities to combat the ROS excess in the cell. Here, we demonstrated that the applied dose of MnDFB enhances antioxidative defenses in soybean following exposure to acid rain and especially to ozone.

  9. Climate change impacts on projections of excess mortality at 2030 using spatially varying ozone-temperature risk surfaces.

    Science.gov (United States)

    Wilson, Ander; Reich, Brian J; Nolte, Christopher G; Spero, Tanya L; Hubbell, Bryan; Rappold, Ana G

    2017-01-01

    We project the change in ozone-related mortality burden attributable to changes in climate between a historical (1995-2005) and near-future (2025-2035) time period while incorporating a non-linear and synergistic effect of ozone and temperature on mortality. We simulate air quality from climate projections varying only biogenic emissions and holding anthropogenic emissions constant, thus attributing changes in ozone only to changes in climate and independent of changes in air pollutant emissions. We estimate non-linear, spatially varying, ozone-temperature risk surfaces for 94 US urban areas using observed data. Using the risk surfaces and climate projections we estimate daily mortality attributable to ozone exceeding 40 p.p.b. (moderate level) and 75 p.p.b. (US ozone NAAQS) for each time period. The average increases in city-specific median April-October ozone and temperature between time periods are 1.02 p.p.b. and 1.94 °F; however, the results varied by region. Increases in ozone because of climate change result in an increase in ozone mortality burden. Mortality attributed to ozone exceeding 40 p.p.b. increases by 7.7% (1.6-14.2%). Mortality attributed to ozone exceeding 75 p.p.b. increases by 14.2% (1.6 28.9%). The absolute increase in excess ozone mortality is larger for changes in moderate ozone levels, reflecting the larger number of days with moderate ozone levels.

  10. Ozone decomposition

    Directory of Open Access Journals (Sweden)

    Batakliev Todor

    2014-06-01

    Full Text Available Catalytic ozone decomposition is of great significance because ozone is a toxic substance commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers. Considerable work has been done on ozone decomposition reported in the literature. This review provides a comprehensive summary of the literature, concentrating on analysis of the physico-chemical properties, synthesis and catalytic decomposition of ozone. This is supplemented by a review on kinetics and catalyst characterization which ties together the previously reported results. Noble metals and oxides of transition metals have been found to be the most active substances for ozone decomposition. The high price of precious metals stimulated the use of metal oxide catalysts and particularly the catalysts based on manganese oxide. It has been determined that the kinetics of ozone decomposition is of first order importance. A mechanism of the reaction of catalytic ozone decomposition is discussed, based on detailed spectroscopic investigations of the catalytic surface, showing the existence of peroxide and superoxide surface intermediates

  11. Monitoring the consequences of decreased ozone protection: The NSF ultraviolet radiation monitoring network

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The effects of decreased protection from ultraviolet radiation are as troubling as the continuing depletion of stratospheric ozone. Evidence exists to clearly link ozone depletion to changes in the antarctic marine environment. Results of two 1992 papers are summarized here. Enhanced exposure to mid-range UV radiation was found to be affecting marine ecosystems with a recorded 6-12 percent reduction in primary productivity directly related to the ozone layer depletion. In another experiment, a model was developed indicating that the ozone hole could reduce near-surface photosynthesis by as much as 12-15 percent. The NSF UV monitoring system in place for these and other experiments uses a spectroradiometer, making hourly, high-resolution measurements of the distribution of UV surface irradiance

  12. What Is the Best Strategy for Enhancing the Effects of Topically Applied Ozonated Oils in Cutaneous Infections?

    Directory of Open Access Journals (Sweden)

    I. Zanardi

    2013-01-01

    Full Text Available Owing to diabetes, atherosclerosis, and ageing, there are several million patients undergoing skin lesions degenerated into infected ulcers with very little tendency to heal and implying a huge socioeconomical cost. Previous medical experience has shown that the daily application of ozonated oil eliminates the infection and promotes a rapid healing. The purpose of the study is the optimization of the antimicrobial effect of ozonated oils by testing in vitro four bacterial species and one yeast without or in the presence of different amounts of human serum. The results obtained suggest that a gentle and continuous removal of debris and exudate is an essential condition for the potent bactericidal effect of ozonated oils. In fact, even small amounts of human serum inactivate ozone derivatives and protect bacteria. The application of ozonated oil preparations is very promising in a variety of skin and mucosal infections. Moreover, ozonated oils are far less expensive than antibiotic preparations.

  13. Toward a biologically significant and usable standard for ozone that will also protect plants

    International Nuclear Information System (INIS)

    Paoletti, Elena; Manning, William J.

    2007-01-01

    Ozone remains an important phytotoxic air pollutant and is also recognized as a significant greenhouse gas. In North America, Europe, and Asia, incidence of high concentrations is decreasing, but background levels are steadily rising. There is a need to develop a biologically significant and usable standard for ozone. We compare the strengths and weaknesses of concentration-based, exposure-based and threshold-based indices, such as SUM60 and AOT40, and examine the O 3 flux concept. We also present major challenges to the development of an air quality standard for ozone that has both biological significance and practicality in usage. - Current standards do not protect vegetation from ozone, but progress is being made

  14. Simulation of Halocarbon Production and Emissions and Effects on Ozone Depletion

    Science.gov (United States)

    Holmes; Ellis

    1997-09-01

    / This paper describes an integrated model that simulates future halocarbon production/emissions and potential ozone depletion. Applications and historical production levels for various halocarbons are discussed first. A framework is then presented for modeling future halocarbon impacts incorporating differences in underlying demands, applications, regulatory mandates, and environmental characteristics. The model is used to simulate the potential impacts of several prominent issues relating to halocarbon production, regulation, and environmental interactions, notably: changes in agricultural methyl bromide use, increases in effectiveness of bromine for ozone depletion, modifications to the elimination schedule for HCFCs, short-term expansion of CFC demand in low use compliance countries, and delays in Russian Federation compliance. Individually, each issue does not unequivocally represent a significant likely increase in long-term atmospheric halogen loading and stratospheric ozone depletion. In combination, however, these impacts could increase peak halogen concentrations and long-term integral halogen loading, resulting in higher levels of stratospheric ozone depletion and longer exposure to increased levels of UV radiation.KEY WORDS: Halocarbons; Ozone depletion; Montreal Protocol; Integrated assessment

  15. High resolution tempo-spatial ozone prediction with SVM and LSTM

    Science.gov (United States)

    Gao, D.; Zhang, Y.; Qu, Z.; Sadighi, K.; Coffey, E.; LIU, Q.; Hannigan, M.; Henze, D. K.; Dick, R.; Shang, L.; Lv, Q.

    2017-12-01

    To investigate and predict the exposure of ozone and other pollutants in urban areas, we utilize data from various infrastructures including EPA, NOAA and RIITS from government of Los Angeles and construct statistical models to conduct ozone concentration prediction in Los Angeles areas at finer spatial and temporal granularity. Our work involves cyber data such as traffic, roads and population data as features for prediction. Two statistical models, Support Vector Machine (SVM) and Long Short-term Memory (LSTM, deep learning method) are used for prediction. . Our experiments show that kernelized SVM gains better prediction performance when taking traffic counts, road density and population density as features, with a prediction RMSE of 7.99 ppb for all-time ozone and 6.92 ppb for peak-value ozone. With simulated NOx from Chemical Transport Model(CTM) as features, SVM generates even better prediction performance, with a prediction RMSE of 6.69ppb. We also build LSTM, which has shown great advantages at dealing with temporal sequences, to predict ozone concentration by treating ozone concentration as spatial-temporal sequences. Trained by ozone concentration measurements from the 13 EPA stations in LA area, the model achieves 4.45 ppb RMSE. Besides, we build a variant of this model which adds spatial dynamics into the model in the form of transition matrix that reveals new knowledge on pollutant transition. The forgetting gate of the trained LSTM is consistent with the delay effect of ozone concentration and the trained transition matrix shows spatial consistency with the common direction of winds in LA area.

  16. Newly divided eosinophils limit ozone-induced airway hyperreactivity in nonsensitized guinea pigs.

    Science.gov (United States)

    Wicher, Sarah A; Jacoby, David B; Fryer, Allison D

    2017-06-01

    Ozone causes vagally mediated airway hyperreactivity and recruits inflammatory cells, including eosinophils, to lungs, where they mediate ozone-induced hyperreactivity 1 day after exposure but are paradoxically protective 3 days later. We aimed to test the role of newly divided eosinophils in ozone-induced airway hyperreactivity in sensitized and nonsensitized guinea pigs. Nonsensitized and sensitized guinea pigs were treated with 5-bromo-2-deoxyuridine (BrdU) to label newly divided cells and were exposed to air or ozone for 4 h. Later (1 or 3 days later), vagally induced bronchoconstriction was measured, and inflammatory cells were harvested from bone marrow, blood, and bronchoalveolar lavage. Ozone induced eosinophil hematopoiesis. One day after ozone, mature eosinophils dominate the inflammatory response and potentiate vagally induced bronchoconstriction. However, by 3 days, newly divided eosinophils have reached the lungs, where they inhibit ozone-induced airway hyperreactivity because depleting them with antibody to IL-5 or a TNF-α antagonist worsened vagally induced bronchoconstriction. In sensitized guinea pigs, both ozone-induced eosinophil hematopoiesis and subsequent recruitment of newly divided eosinophils to lungs 3 days later failed to occur. Thus mature eosinophils dominated the ozone-induced inflammatory response in sensitized guinea pigs. Depleting these mature eosinophils prevented ozone-induced airway hyperreactivity in sensitized animals. Ozone induces eosinophil hematopoiesis and recruitment to lungs, where 3 days later, newly divided eosinophils attenuate vagally mediated hyperreactivity. Ozone-induced hematopoiesis of beneficial eosinophils is blocked by a TNF-α antagonist or by prior sensitization. In these animals, mature eosinophils are associated with hyperreactivity. Thus interventions targeting eosinophils, although beneficial in atopic individuals, may delay resolution of airway hyperreactivity in nonatopic individuals. Copyright

  17. Ozone-surface reactions in five homes: surface reaction probabilities, aldehyde yields, and trends.

    Science.gov (United States)

    Wang, H; Morrison, G

    2010-06-01

    Field experiments were conducted in five homes during three seasons (summer 2005, summer 2006 and winter 2007) to quantify ozone-initiated secondary aldehyde yields, surface reaction probabilities, and trends any temporal over a 1.5-year interval. Surfaces examined include living room carpets, bedroom carpets, kitchen floors, kitchen counters, and living room walls. Reaction probabilities for all surfaces for all seasons ranged from 9.4 x 10(-8) to 1.0 x 10(-4). There were no significant temporal trends in reaction probabilities for any surfaces from summer 2005 to summer 2006, nor over the entire 1.5-year period, indicating that it may take significantly longer than this period for surfaces to exhibit any 'ozone aging' or lowering of ozone-surface reactivity. However, all surfaces in three houses exhibited a significant decrease in reaction probabilities from summer 2006 to winter 2007. The total yield of aldehydes for the summer of 2005 were nearly identical to that for summer of 2006, but were significantly higher than for winter 2007. We also observed that older carpets were consistently less reactive than in newer carpets, but that countertops remained consistently reactive, probably because of occupant activities such as cooking and cleaning. Ozone reactions taking place at indoor surfaces significantly influence personal exposure to ozone and volatile reaction products. These field studies show that indoor surfaces only slowly lose their ability to react with ozone over several year time frames, and that this is probably because of a combination of large reservoirs of reactive coatings and periodic additions of reactive coatings in the form of cooking, cleaning, and skin-oil residues. When considering exposure to ozone and its reaction products and in the absence of dramatic changes in occupancy, activities or furnishings, indoor surface reactivity is expected to change very slowly.

  18. [Health impact of ozone in 13 Italian cities].

    Science.gov (United States)

    Mitis, Francesco; Iavarone, Ivano; Martuzzi, Marco

    2007-01-01

    to estimate the health impact of ozone in 13 Italian cities over 200,000 inhabitants and to produce basic elements to permit the reproducibility of the study in other urban locations. the following data have been used: population data (2001), health data (2001 or from scientific literature), environmental data (2002-2004), from urban background monitoring station and concentration/response risk coefficients derived from recent metanalyses. The indicators SOMO35 and SOMO0 have been used as a proxi of the average exposure to calcolate attributable deaths (and years of life lost) and several causes of morbility for ozone concentrations over 70 microg/m3. acute mortality for all causes and for cardiovascular mortality, respiratory-related hospital admissions in elderly, asthma exacerbation in children and adults, minor restricted activity days, lower respiratory symptoms in children. over 500 (1900) deaths, the 0.6% (2.1%) of total mortality, equivalent to about 6000 (22,000) years of life lost are attributable to ozone levels over 70 microg/m3 in the 13 Italian cities under study. Larger figures, in the order of thousands, are attributable to less severe morbidity outcomes. The health impact of ozone in Italian towns is relevant in terms of acute mortality and morbidity, although less severe than PM10 impact. Background ozone levels are increasing. Abatement strategies for ozone concentrations should consider the whole summer and not only "peak" days and look at policies limiting the concentration of precursors produced by traffic sources. Relevant health benefits can be obtained also under levels proposed as guidelines in the present environmental regulations.

  19. Significant increase of surface ozone at a rural site, north of eastern China

    Directory of Open Access Journals (Sweden)

    Z. Ma

    2016-03-01

    Full Text Available Ozone pollution in eastern China has become one of the top environmental issues. Quantifying the temporal trend of surface ozone helps to assess the impacts of the anthropogenic precursor reductions and the likely effects of emission control strategies implemented. In this paper, ozone data collected at the Shangdianzi (SDZ regional atmospheric background station from 2003 to 2015 are presented and analyzed to obtain the variation in the trend of surface ozone in the most polluted region of China, north of eastern China or the North China Plain. A modified Kolmogorov–Zurbenko (KZ filter method was performed on the maximum daily average 8 h (MDA8 concentrations of ozone to separate the contributions of different factors from the variation of surface ozone and remove the influence of meteorological fluctuations on surface ozone. Results reveal that the short-term, seasonal and long-term components of ozone account for 36.4, 57.6 and 2.2 % of the total variance, respectively. The long-term trend indicates that the MDA8 has undergone a significant increase in the period of 2003–2015, with an average rate of 1.13 ± 0.01 ppb year−1 (R2 = 0.92. It is found that meteorological factors did not significantly influence the long-term variation of ozone and the increase may be completely attributed to changes in emissions. Furthermore, there is no significant correlation between the long-term O3 and NO2 trends. This study suggests that emission changes in VOCs might have played a more important role in the observed increase of surface ozone at SDZ.

  20. Nicotiana tabacum as model for ozone - plant surface reactions

    Science.gov (United States)

    Jud, Werner; Fischer, Lukas; Wohlfahrt, Georg; Tissier, Alain; Canaval, Eva; Hansel, Armin

    2015-04-01

    Elevated tropospheric ozone concentrations are considered a toxic threat to plants, responsible for global crop losses with associated economic costs of several billion dollars per year. The ensuing injuries have been related to the uptake of ozone through the stomatal pores and oxidative effects damaging the internal leaf tissue. A striking question of current research is the environment and plant specific partitioning of ozone loss between gas phase, stomatal or plant surface sink terms. Here we show results from ozone fumigation experiments using various Nicotiana Tabacum varieties, whose surfaces are covered with different amounts of unsaturated diterpenoids exuded by their glandular trichomes. Exposure to elevated ozone levels (50 to 150 ppbv) for 5 to 15 hours in an exceptionally clean cuvette system did neither result in a reduction of photosynthesis nor caused any visible leaf damage. Both these ozone induced stress effects have been observed previously in ozone fumigation experiments with the ozone sensitive tobacco line Bel-W3. In our case ozone fumigation was accompanied by a continuous release of oxygenated volatile organic compounds, which could be clearly associated to their condensed phase precursors for the first time. Gas phase reactions of ozone were avoided by choosing a high enough gas exchange rate of the plant cuvette system. In the case of the Ambalema variety, that is known to exude only the diterpenoid cis-abienol, ozone fumigation experiments yield the volatiles formaldehyde and methyl vinyl ketone (MVK). The latter could be unequivocally separated from isomeric methacrolein (MACR) by the aid of a Selective Reagent Ion Time-of-Flight Mass Spectrometer (SRI-ToF-MS), which was switched every six minutes from H3O+ to NO+ primary ion mode and vice versa. Consistent with the picture of an ozone protection mechanism caused by reactive diterpenoids at the leaf surface are the results from dark-light experiments. The ozone loss obtained from the

  1. Ozone Therapy on Rats Submitted to Subtotal Nephrectomy: Role of Antioxidant System

    Directory of Open Access Journals (Sweden)

    José Luis Calunga

    2005-01-01

    Full Text Available Chronic renal failure (CRF represents a world health problem. Ozone increases the endogenous antioxidant defense system, preserving the cell redox state. The aim of this study is to evaluate the effect of ozone/oxygen mixture in the renal function, morphology, and biochemical parameters, in an experimental model of CRF (subtotal nephrectomy. Ozone/oxygen mixture was applied daily, by rectal insufflation (0.5 mg/kg for 15 sessions after the nephrectomy. Renal function was evaluated, as well as different biochemical parameters, at the beginning and at the end of the study (10 weeks. Renal plasmatic flow (RPF, glomerular filtration rate (GFR, the urine excretion index, and the sodium and potassium excretions (as a measurement of tubular function in the ozone group were similar to those in Sham group. Nevertheless, nephrectomized rats without ozone (positive control group showed the lowest RPF, GFR, and urine excretion figures, as well as tubular function. Animals treated with ozone showed systolic arterial pressure (SAP figures lower than those in the positive control group, but higher values compared to Sham group. Serum creatinine values and protein excretion in 24 hours in the ozone group were decreased compared with nephrectomized rats, but were still higher than normal values. Histological study demonstrated that animals treated with ozone showed less number of lesions in comparison with nephrectomized rats. Thiobarbituric acid reactive substances were significantly increased in nephrectomized and ozone-treated nephrectomized rats in comparison with Sham group. In the positive control group, superoxide dismutase (SOD and catalase (CAT showed the lowest figures in comparison with the other groups. However, ozone/oxygen mixture induced a significant stimulation in the enzymatic activity of CAT, SOD, and glutathione peroxidase, as well as reduced glutathione in relation with Sham and positive control groups. In this animal model of CRF, ozone

  2. Ozone modifies the metabolic and endocrine response to glucose: Reproduction of effects with the stress hormone corticosterone.

    Science.gov (United States)

    Thomson, Errol M; Pilon, Shinjini; Guénette, Josée; Williams, Andrew; Holloway, Alison C

    2018-03-01

    Air pollution is associated with increased incidence of metabolic disease (e.g. metabolic syndrome, obesity, diabetes); however, underlying mechanisms are poorly understood. Air pollutants increase the release of stress hormones (human cortisol, rodent corticosterone), which could contribute to metabolic dysregulation. We assessed acute effects of ozone, and stress axis involvement, on glucose tolerance and on the metabolic (triglyceride), endocrine/energy regulation (insulin, glucagon, GLP-1, leptin, ghrelin, corticosterone), and inflammatory/endothelial (TNF, IL-6, VEGF, PAI-1) response to exogenous glucose. Male Fischer-344 rats were exposed to clean air or 0.8 ppm ozone for 4 h in whole body chambers. Hypothalamic-pituitary-adrenal (HPA) axis involvement in ozone effects was tested through subcutaneous administration of the glucocorticoid synthesis inhibitor metyrapone (50 mg/kg body weight), corticosterone (10 mg/kg body weight), or vehicle (40% propylene glycol) prior to exposure. A glucose tolerance test (2 g/kg body weight glucose) was conducted immediately after exposure, with blood samples collected at 0, 30, 60, 90, and 120 min. Ozone exposure impaired glucose tolerance, an effect accompanied by increased plasma triglycerides but no impairment of insulin release. Ozone diminished glucagon, GLP-1, and ghrelin responses to glucose, but did not significantly impact inflammatory/endothelial analytes. Metyrapone reduced corticosterone but increased glucose and triglycerides, complicating evaluation of the impact of glucocorticoid inhibition. However, administration of corticosterone reproduced the profile of ozone effects, supporting a role for the HPA axis. The results show that ozone-dependent changes in glucose tolerance are accompanied by altered metabolic and endocrine responses to glucose challenge that are reproduced by exogenous stress hormone. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  3. The Ozone Monitoring Instrument: overview of 14 years in space

    Directory of Open Access Journals (Sweden)

    P. F. Levelt

    2018-04-01

    Full Text Available This overview paper highlights the successes of the Ozone Monitoring Instrument (OMI on board the Aura satellite spanning a period of nearly 14 years. Data from OMI has been used in a wide range of applications and research resulting in many new findings. Due to its unprecedented spatial resolution, in combination with daily global coverage, OMI plays a unique role in measuring trace gases important for the ozone layer, air quality, and climate change. With the operational very fast delivery (VFD; direct readout and near real-time (NRT availability of the data, OMI also plays an important role in the development of operational services in the atmospheric chemistry domain.

  4. Hyaluronan signaling during ozone-induced lung injury requires TLR4, MyD88, and TIRAP.

    Directory of Open Access Journals (Sweden)

    Zhuowei Li

    Full Text Available Ozone exposure is associated with exacerbation of reactive airways disease. We have previously reported that the damage-associated molecular pattern, hyaluronan, is required for the complete biological response to ambient ozone and that hyaluronan fragments signal through toll-like receptor 4 (TLR4. In this study, we further investigated the role of TLR4 adaptors in ozone-induced airway hyperresponsiveness (AHR and the direct response to hyaluronan fragments (HA. Using a murine model of AHR, C57BL/6J, TLR4-/-, MyD88-/-, and TIRAP-/- mice were characterized for AHR after exposure to either ozone (1 ppm × 3 h or HA fragments. Animals were characterized for AHR with methacholine challenge, cellular inflammation, lung injury, and production of pro-inflammatory cytokines. Ozone-exposed C57BL/6J mice developed cellular inflammation, lung injury, pro-inflammatory cytokines, and AHR, while mice deficient in TLR4, MyD88 or TIRAP demonstrated both reduced AHR and reduced levels of pro-inflammatory cytokines including TNFα, IL-1β, MCP-1, IL-6 and KC. The level of hyaluronan was increased after inhalation of ozone in each strain of mice. Direct challenge of mice to hyaluronan resulted in AHR in C57BL/6J mice, but not in TLR4-/-, MyD88-/-, or TIRAP-/- mice. HA-induced cytokine production in wild-type mice was significantly reduced in TLR4-/-, MyD88-/-, or TIRAP-/- mice. In conclusion, our findings support that ozone-induced airway hyperresponsiveness is dependent on the HA-TLR4-MyD88-TIRAP signaling pathway.

  5. The impacts of surface ozone pollution on winter wheat productivity in China – An econometric approach

    International Nuclear Information System (INIS)

    Yi, Fujin; Jiang, Fei; Zhong, Funing; Zhou, Xun; Ding, Aijun

    2016-01-01

    The impact of surface ozone pollution on winter wheat yield is empirically estimated by considering socio-economic and weather determinants. This research is the first to use an economic framework to estimate the ozone impact, and a unique county-level panel is employed to examine the impact of the increasing surface ozone concentration on the productivity of winter wheat in China. In general, the increment of surface ozone concentration during the ozone-sensitive period of winter wheat is determined to be harmful to its yield, and a conservative reduction of ozone pollution could significantly increase China's wheat supply. - Highlights: • We examine the impacts of the surface ozone exposure on winter wheat yield in China. • An econometric method is used to measure the ozone impacts. • The results conclude that surface ozone is harmful to winter wheat yield in China. • We confirm that stress conditions such as drought and air particles can mitigate the adverse effect of ozone. - Surface ozone pollution is harmful to winter wheat yield in China by considering socio-economic determinants, weather, and other stress conditions like drought and air particles.

  6. Ozone decay in chemical reactor for ozone-dynamical disintegration of used tyres

    International Nuclear Information System (INIS)

    Golota, V.I.; Manuilenko, O.V.; Taran, G.V.; Dotsenko, Yu.V.; Pismenetskii, A.S.; Zamuriev, A.A.; Benitskaja, V.A.

    2011-01-01

    The ozone decay kinetics in the chemical reactor intended for used tyres disintegration is investigated experimentally and theoretically. Ozone was synthesized in barrierless ozonizers based on the streamer discharge. The chemical reactor for tyres disintegration in the ozone-air environment represents the cylindrical chamber, which feeds from the ozonizer by ozone-air mixture with the specified rate of volume flow, and with known ozone concentration. The output of the used mixture, which rate of volume flow is also known, is carried out through the ozone destructor. As a result of ozone decay in the volume and on the reactor walls, and output of the used mixture from the reactor, the ozone concentration in the reactor depends from time. In the paper, the analytical expression for dependence of ozone concentration in the reactor from time and from the parameters of a problem such as the volumetric feed rate, ozone concentration on the input in the reactor, volume flow rate of the used mixture, the volume of the reactor and the area of its internal surface is obtained. It is shown that experimental results coincide with good accuracy with analytical ones.

  7. Comparison of spectrophotometric and radioisotopic methods for the assay of Rubisco in ozone-treated plants

    International Nuclear Information System (INIS)

    Reid, C.D.; Tissue, D.T.; Fiscus, E.L.; Strain, B.R.

    1997-01-01

    Radioisotopic and spectrophotometric assays for ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) initial and final activities and Rubisco content were compared in plants chronically exposed to ozone (O 3 ) in a greenhouse and the field. In a greenhouse experiment, Glycine max was treated in exposure chambers with either charcoal-filtered air (CF air) or 100 nl O 3 l -1 for 6 h daily during vegetative growth. Samples were collected after 7 days of exposure. In a field experiment, G. max was treated in open-top chambers with either CF air or non-filtered air with O 3 added at 1.5 times ambient O 3 for 12 h daily. Average daily O 3 concentrations were 21 and 92 nl l -1 in the CF and O 3 treatments, respectively. Samples were collected during vegetative and reproductive growth. Both assays generally yielded comparable Rubisco initial and final activities for greenhouse-grown plants regardless of the O 3 treatment. However for field-grown plants, Rubisco initial and final activities average 15 and 23% lower when assayed by the spectrophotometric rather than the radioisotopic method. For Rubisco content estimated by the spectrophotometric method, lower values for the regression of Rubisco activity vs concentration of carboxyarabinitol-1.5-bisphosphate were observed in O 3- than in CF-treated plants. Both assays yielded comparable Rubisco contents in the greenhouse and in the field although the variation was larger with the spectrophotometric method in field-grown plants. Growth conditions, field vs greenhouse, were more critical to the spectrophotometric assay performance than the O 3 treatments for measurement of Rubisco activity and content. (au) 40 refs

  8. Effect of pulsed corona discharge voltage and feed gas flow rate on dissolved ozone concentration

    International Nuclear Information System (INIS)

    Prasetyaningrum, A.; Ratnawati,; Jos, B.

    2015-01-01

    Ozonization is one of the methods extensively used for water purification and degradation of organic materials. Ozone (O 3 ) is recognized as a powerful oxidizing agent. Due to its strong oxidability and better environmental friendless, ozone increasing being used in domestic and industrial applications. Current technology in ozone production utilizes several techniques (corona discharge, ultra violet radiation and electrolysis). This experiment aimed to evaluating effect of voltage and gas flow rate on ozone production with corona discharge. The system consists of two net-type stainless steel electrode placed in a dielectric barrier. Three pulsed voltage (20, 30, 40 KV) and flow rate (5, 10, 15 L/min) were prepare for operation variable at high frequency (3.7 kHz) with AC pulsed power supply. The dissolved ozone concentration depends on the applied high-voltage level, gas flow rate and the discharge exposure duration. The ozone concentration increases with decreasing gas flow rate. Dissolved ozone concentrations greater than 200 ppm can be obtained with a minimum voltage 40 kV

  9. Effect of pulsed corona discharge voltage and feed gas flow rate on dissolved ozone concentration

    Science.gov (United States)

    Prasetyaningrum, A.; Ratnawati, Jos, B.

    2015-12-01

    Ozonization is one of the methods extensively used for water purification and degradation of organic materials. Ozone (O3) is recognized as a powerful oxidizing agent. Due to its strong oxidability and better environmental friendless, ozone increasing being used in domestic and industrial applications. Current technology in ozone production utilizes several techniques (corona discharge, ultra violet radiation and electrolysis). This experiment aimed to evaluating effect of voltage and gas flow rate on ozone production with corona discharge. The system consists of two net-type stainless steel electrode placed in a dielectric barrier. Three pulsed voltage (20, 30, 40 KV) and flow rate (5, 10, 15 L/min) were prepare for operation variable at high frequency (3.7 kHz) with AC pulsed power supply. The dissolved ozone concentration depends on the applied high-voltage level, gas flow rate and the discharge exposure duration. The ozone concentration increases with decreasing gas flow rate. Dissolved ozone concentrations greater than 200 ppm can be obtained with a minimum voltage 40 kV.

  10. Effect of pulsed corona discharge voltage and feed gas flow rate on dissolved ozone concentration

    Energy Technology Data Exchange (ETDEWEB)

    Prasetyaningrum, A., E-mail: ajiprasetyaningrum@gmail.com; Ratnawati,; Jos, B. [Department of Chemical Engineering, Faculty of Engineering, Diponegoro University Jl. Prof. H. Soedarto Tembalang, Semarang, Central Java, Indonesia, 50276 (Indonesia)

    2015-12-29

    Ozonization is one of the methods extensively used for water purification and degradation of organic materials. Ozone (O{sub 3}) is recognized as a powerful oxidizing agent. Due to its strong oxidability and better environmental friendless, ozone increasing being used in domestic and industrial applications. Current technology in ozone production utilizes several techniques (corona discharge, ultra violet radiation and electrolysis). This experiment aimed to evaluating effect of voltage and gas flow rate on ozone production with corona discharge. The system consists of two net-type stainless steel electrode placed in a dielectric barrier. Three pulsed voltage (20, 30, 40 KV) and flow rate (5, 10, 15 L/min) were prepare for operation variable at high frequency (3.7 kHz) with AC pulsed power supply. The dissolved ozone concentration depends on the applied high-voltage level, gas flow rate and the discharge exposure duration. The ozone concentration increases with decreasing gas flow rate. Dissolved ozone concentrations greater than 200 ppm can be obtained with a minimum voltage 40 kV.

  11. Ozone pollution and ozone biomonitoring in European cities Part II. Ozone-induced plant injury and its relationship with descriptors of ozone pollution

    DEFF Research Database (Denmark)

    Klumpp, A.; Ansel, W.; Klumpp, G.

    2006-01-01

    within local networks were relatively small, but seasonal and inter-annual differences were strong due to the variability of meteorological conditions and related ozone concentrations. The 2001 data revealed a significant relationship between foliar injury degree and various descriptors of ozone...... pollution such as mean value, AOT20 and AOT40. Examining individual sites of the local monitoring networks separately, however, yielded noticeable differences. Some sites showed no association between ozone pollution and ozone-induced effects, whereas others featured almost linear relationships...

  12. Studies on the developmental toxicity of ozone: postnatal effects. [Rats

    Energy Technology Data Exchange (ETDEWEB)

    Kavlock, R J; Meyer, E; Grabowski, C T

    1980-01-01

    Pregnant rats were exposed to either 0, 1.0, or 1.5 ppm ozone during either mid gestation (Days 9-12) or late gestation (Days 17-20). The dams were allowed to deliver and the early morphological and behavioral development of their pups was monitored. Both exposure regimens transiently reduced neonatal growth rates. The late gestation exposure regimen produced retardations in early reflex development and in open field behavior. Finally, several males from this exposure regimen remained permanently stunted in growth.

  13. Inactivation of Template-Directed Misfolding of Infectious Prion Protein by Ozone

    Science.gov (United States)

    Ding, Ning; Price, Luke M.; Braithwaite, Shannon L.; Balachandran, Aru; Belosevic, Miodrag

    2012-01-01

    Misfolded prions (PrPSc) are well known for their resistance to conventional decontamination processes. The potential risk of contamination of the water environment, as a result of disposal of specified risk materials (SRM), has raised public concerns. Ozone is commonly utilized in the water industry for inactivation of microbial contaminants and was tested in this study for its ability to inactivate prions (263K hamster scrapie = PrPSc). Treatment variables included initial ozone dose (7.6 to 25.7 mg/liter), contact time (5 s and 5 min), temperature (4°C and 20°C), and pH (pH 4.4, 6.0, and 8.0). Exposure of dilute suspensions of the infected 263K hamster brain homogenates (IBH) (0.01%) to ozone resulted in the in vitro destruction of the templating properties of PrPSc, as measured by the protein misfolding cyclic amplification (PMCA) assay. The highest levels of prion inactivation (≥4 log10) were observed with ozone doses of 13.0 mg/liter, at pH 4.4 and 20°C, resulting in a CT (the product of residual ozone concentration and contact time) value as low as 0.59 mg · liter−1 min. A comparison of ozone CT requirements among various pathogens suggests that prions are more susceptible to ozone degradation than some model bacteria and protozoa and that ozone treatment may be an effective solution for inactivating prions in water and wastewater. PMID:22138993

  14. Reconciliation of Halogen-Induced Ozone Loss with the Total-Column Ozone Record

    Science.gov (United States)

    Shepherd, T. G.; Plummer, D. A.; Scinocca, J. F.; Hegglin, M. I.; Fioletov, V. E.; Reader, M. C.; Remsberg, E.; von Clarmann, T.; Wang, H. J.

    2014-01-01

    The observed depletion of the ozone layer from the 1980s onwards is attributed to halogen source gases emitted by human activities. However, the precision of this attribution is complicated by year-to-year variations in meteorology, that is, dynamical variability, and by changes in tropospheric ozone concentrations. As such, key aspects of the total-column ozone record, which combines changes in both tropospheric and stratospheric ozone, remain unexplained, such as the apparent absence of a decline in total-column ozone levels before 1980, and of any long-term decline in total-column ozone levels in the tropics. Here we use a chemistry-climate model to estimate changes in halogen-induced ozone loss between 1960 and 2010; the model is constrained by observed meteorology to remove the eects of dynamical variability, and driven by emissions of tropospheric ozone precursors to separate out changes in tropospheric ozone. We show that halogen-induced ozone loss closely followed stratospheric halogen loading over the studied period. Pronounced enhancements in ozone loss were apparent in both hemispheres following the volcanic eruptions of El Chichon and, in particular, Mount Pinatubo, which significantly enhanced stratospheric aerosol loads. We further show that approximately 40% of the long-term non-volcanic ozone loss occurred before 1980, and that long-term ozone loss also occurred in the tropical stratosphere. Finally, we show that halogeninduced ozone loss has declined by over 10% since stratospheric halogen loading peaked in the late 1990s, indicating that the recovery of the ozone layer is well underway.

  15. Effects of ozone on growth, yield and leaf gas exchange rates of two Bangladeshi cultivars of wheat (Triticum aestivum L.)

    International Nuclear Information System (INIS)

    Akhtar, Nahid; Yamaguchi, Masahiro; Inada, Hidetoshi; Hoshino, Daiki; Kondo, Taisuke; Izuta, Takeshi

    2010-01-01

    To clarify the effects of O 3 on crop plants cultivated in Bangladesh, two Bangladeshi wheat cultivars (Sufi and Bijoy) were grown in plastic boxes filled with Andisol and exposed daily to charcoal-filtered air or O 3 at 60 and 100 nl l -1 (10:00-17:00) from 13 March to 4 June 2008. The whole-plant dry mass and grain yield per plant of the two cultivars at the final harvest were significantly reduced by the exposure to O 3 . Although there was no significant effect of O 3 on stomatal diffusive conductance to H 2 O of flag leaf, net photosynthetic rate of the leaf was significantly reduced by the exposure to O 3. The sensitivity of growth, yield, yield components and leaf gas exchange rates to O 3 was not significantly different between the two cultivars. The results obtained in the present study suggest that ambient levels of O 3 may detrimentally affect wheat production in Bangladesh. - The exposure to ambient levels of ozone decreases growth, yield and leaf gas exchange rates of two Bangladeshi cultivars of wheat.

  16. Ozone exposure, vitamin C intake, and genetic susceptibility of asthmatic children in Mexico City: a cohort study

    Directory of Open Access Journals (Sweden)

    Moreno-Macías Hortensia

    2013-02-01

    Full Text Available Abstract Background We previously reported that asthmatic children with GSTM1 null genotype may be more susceptible to the acute effect of ozone on the small airways and might benefit from antioxidant supplementation. This study aims to assess the acute effect of ozone on lung function (FEF25-75 in asthmatic children according to dietary intake of vitamin C and the number of putative risk alleles in three antioxidant genes: GSTM1, GSTP1 (rs1695, and NQO1 (rs1800566. Methods 257 asthmatic children from two cohort studies conducted in Mexico City were included. Stratified linear mixed models with random intercepts and random slopes on ozone were used. Potential confounding by ethnicity was assessed. Analyses were conducted under single gene and genotype score approaches. Results The change in FEF25-75 per interquartile range (60 ppb of ozone in persistent asthmatic children with low vitamin C intake and GSTM1 null was −91.2 ml/s (p = 0.06. Persistent asthmatic children with 4 to 6 risk alleles and low vitamin C intake showed an average decrement in FEF25-75 of 97.2 ml/s per 60 ppb of ozone (p = 0.03. In contrast in children with 1 to 3 risk alleles, acute effects of ozone on FEF25-75 did not differ by vitamin C intake. Conclusions Our results provide further evidence that asthmatic children predicted to have compromised antioxidant defense by virtue of genetic susceptibility combined with deficient antioxidant intake may be at increased risk of adverse effects of ozone on pulmonary function.

  17. Generation of ozone and safety aspects in an accelerator facility of BARC

    International Nuclear Information System (INIS)

    Dubey, Praveen; Sawatkar, Aparna R.; Sathe, Arun P.; Soundararajan, S.; Sarma, K.S.S.

    2009-01-01

    Industrial electron beam accelerators up to 10 MeV are commonly employed for different applications. During normal operation of an accelerator, the principal hazard is the high radiation level produced. Experiments and applications in which the electron beam is used to irradiate materials outside the accelerator vacuum system are associated with problems such as radiation damage and production of considerable quantities of ozone. The possible generation of ozone during the operation of an electron beam accelerator is of special interest due to reactivity, corrosivity and the toxic characteristics of ozone. Industrial hygiene surveys were conducted to estimate the airborne concentration of ozone during operations of the electron beam accelerator (Type: ILU-6; 2 MeV; 20 KW) at varied operating parameters. The ozone concentration in the accelerator room was measured at different powers of the accelerator and the ozone decay pattern was also observed after beam shut down. Ozone in the accelerator room was measured by different methods such as colorimetry using neutral buffered potassium iodide, chemiluminescence method using ethylene and by using electrochemical sensor. An air velocity meter was used to measure the linear air velocity across the exhaust grills and the number of air changes available in the accelerator room was calculated. Necessary control measures were suggested to keep the occupational exposure of the personnel to ozone concentrations well within the Threshold Limit Values. (author)

  18. Measurement of the initial phase of ozone decomposition in water and wastewater by means of a continuous quench-flow system: application to disinfection and pharmaceutical oxidation.

    Science.gov (United States)

    Buffle, Marc-Olivier; Schumacher, Jochen; Salhi, Elisabeth; Jekel, Martin; von Gunten, Urs

    2006-05-01

    Due to a lack of adequate experimental techniques, the kinetics of the first 20s of ozone decomposition in natural water and wastewater is still poorly understood. Introducing a continuous quench-flow system (CQFS), measurements starting 350 ms after ozone addition are presented for the first time. Very high HO. to O3 exposures ratios (Rct=integralHO.dt/integralO3dt) reveal that the first 20s of ozonation present oxidation conditions that are similar to ozone-based advanced oxidation processes (AOP). The oxidation of carbamazepine could be accurately modeled using O3 and HO. exposures measured with CQFS during wastewater ozonation. These results demonstrate the applicability of bench scale determined second-order rate constants for wastewater ozonation. Important degrees of pharmaceutical oxidation and microbial inactivation are predicted, indicating that a significant oxidation potential is available during wastewater ozonation, even when ozone is entirely decomposed in the first 20s.

  19. Regulation of ozone-induced lung inflammation and injury by the β-galactoside-binding lectin galectin-3

    International Nuclear Information System (INIS)

    Sunil, Vasanthi R.; Francis, Mary; Vayas, Kinal N.; Cervelli, Jessica A.; Choi, Hyejeong; Laskin, Jeffrey D.; Laskin, Debra L.

    2015-01-01

    Macrophages play a dual role in ozone toxicity, contributing to both pro- and anti-inflammatory processes. Galectin-3 (Gal-3) is a lectin known to regulate macrophage activity. Herein, we analyzed the role of Gal-3 in the response of lung macrophages to ozone. Bronchoalveolar lavage (BAL) and lung tissue were collected 24–72 h after exposure (3 h) of WT and Gal-3 -/- mice to air or 0.8 ppm ozone. In WT mice, ozone inhalation resulted in increased numbers of proinflammatory (Gal-3 + , iNOS + ) and anti-inflammatory (MR-1 + ) macrophages in the lungs. While accumulation of iNOS + macrophages was attenuated in Gal-3 -/- mice, increased numbers of enlarged MR-1 + macrophages were noted. This correlated with increased numbers of macrophages in BAL. Flow cytometric analysis showed that these cells were CD11b + and consisted mainly (> 97%) of mature (F4/80 + CD11c + ) proinflammatory (Ly6GLy6C hi ) and anti-inflammatory (Ly6GLy6C lo ) macrophages. Increases in both macrophage subpopulations were observed following ozone inhalation. Loss of Gal-3 resulted in a decrease in Ly6C hi macrophages, with no effect on Ly6C lo macrophages. CD11b + Ly6G + Ly6C + granulocytic (G) and monocytic (M) myeloid derived suppressor cells (MDSC) were also identified in the lung after ozone. In Gal-3 -/- mice, the response of G-MDSC to ozone was attenuated, while the response of M-MDSC was heightened. Changes in inflammatory cell populations in the lung of ozone treated Gal-3 -/- mice were correlated with reduced tissue injury as measured by cytochrome b5 expression. These data demonstrate that Gal-3 plays a role in promoting proinflammatory macrophage accumulation and toxicity in the lung following ozone exposure. - Highlights: • Multiple monocytic-macrophage subpopulations accumulate in the lung after ozone inhalation. • Galectin-3 plays a proinflammatory role in ozone-induced lung injury. • In the absence of gal-3, inflammatory cells with a myeloid derived suppressor cell phenotype

  20. Sensitivity of antibiotic resistant and antibiotic susceptible Escherichia coli, Enterococcus and Staphylococcus strains against ozone.

    Science.gov (United States)

    Heß, Stefanie; Gallert, Claudia

    2015-12-01

    Tolerance of antibiotic susceptible and antibiotic resistant Escherichia coli, Enterococcus and Staphylococcus strains from clinical and wastewater samples against ozone was tested to investigate if ozone, a strong oxidant applied for advanced wastewater treatment, will affect the release of antibiotic resistant bacteria into the aquatic environment. For this purpose, the resistance pattern against antibiotics of the mentioned isolates and their survival after exposure to 4 mg/L ozone was determined. Antibiotic resistance (AR) of the isolates was not correlating with higher tolerance against ozone. Except for ampicillin resistant E. coli strains, which showed a trend towards increased resistance, E. coli strains that were also resistant against cotrimoxazol, ciprofloxacin or a combination of the three antibiotics were similarly or less resistant against ozone than antibiotic sensitive strains. Pigment-producing Enterococcus casseliflavus and Staphylococcus aureus seemed to be more resistant against ozone than non-pigmented species of these genera. Furthermore, aggregation or biofilm formation apparently protected bacteria in subsurface layers from inactivation by ozone. The relatively large variance of tolerance against ozone may indicate that resistance to ozone inactivation most probably depends on several factors, where AR, if at all, does not play a major role.

  1. CONTRIBUTION TO INDOOR OZONE LEVELS OF AN OZONE GENERATOR

    Science.gov (United States)

    This report gives results of a study of a commonly used commercially available ozone generator, undertaken to determine its impact on indoor ozone levels. xperiment were conducted in a typical mechanically ventilated office and in a test house. he generated ozone and the in-room ...

  2. Development of Compact Ozonizer with High Ozone Output by Pulsed Power

    Science.gov (United States)

    Tanaka, Fumiaki; Ueda, Satoru; Kouno, Kanako; Sakugawa, Takashi; Akiyama, Hidenori; Kinoshita, Youhei

    Conventional ozonizer with a high ozone output using silent or surface discharges needs a cooling system and a dielectric barrier, and therefore becomes a large machine. A compact ozonizer without the cooling system and the dielectric barrier has been developed by using a pulsed power generated discharge. The wire to plane electrodes made of metal have been used. However, the ozone output was low. Here, a compact and high repetition rate pulsed power generator is used as an electric source of a compact ozonizer. The ozone output of 6.1 g/h and the ozone yield of 86 g/kWh are achieved at 500 pulses per second, input average power of 280 W and an air flow rate of 20 L/min.

  3. Ozone affects growth and development of Pieris brassicae on the wild host plant Brassica nigra

    International Nuclear Information System (INIS)

    Khaling, Eliezer; Papazian, Stefano; Poelman, Erik H.; Holopainen, Jarmo K.; Albrectsen, Benedicte R.; Blande, James D.

    2015-01-01

    When plants are exposed to ozone they exhibit changes in both primary and secondary metabolism, which may affect their interactions with herbivorous insects. Here we investigated the performance and preferences of the specialist herbivore Pieris brassicae on the wild plant Brassica nigra under elevated ozone conditions. The direct and indirect effects of ozone on the plant-herbivore system were studied. In both cases ozone exposure had a negative effect on P. brassicae development. However, in dual-choice tests larvae preferentially consumed plant material previously fumigated with the highest concentration tested, showing a lack of correlation between larval preference and performance on ozone exposed plants. Metabolomic analysis of leaf material subjected to combinations of ozone and herbivore-feeding, and focussing on known defence metabolites, indicated that P. brassicae behaviour and performance were associated with ozone-induced alterations to glucosinolate and phenolic pools. - Highlights: • We examined the effects of ozone on Pieris brassicae performance and preference. • We studied ozone and herbivore induced changes in the metabolome of Brassica nigra. • The performance of P. brassicae did not correlate with preference of ozonated plants. • Ozone and herbivore-feeding stress changes the phytochemical pools of B. nigra. - Ozone indirectly reduces herbivore performance, which is associated with change in phytochemical pools, but does not correlate with host plant preference

  4. Impacts of ozone air pollution and temperature extremes on crop yields: Spatial variability, adaptation and implications for future food security

    Science.gov (United States)

    Tai, Amos P. K.; Val Martin, Maria

    2017-11-01

    Ozone air pollution and climate change pose major threats to global crop production, with ramifications for future food security. Previous studies of ozone and warming impacts on crops typically do not account for the strong ozone-temperature correlation when interpreting crop-ozone or crop-temperature relationships, or the spatial variability of crop-to-ozone sensitivity arising from varietal and environmental differences, leading to potential biases in their estimated crop losses. Here we develop an empirical model, called the partial derivative-linear regression (PDLR) model, to estimate the spatial variations in the sensitivities of wheat, maize and soybean yields to ozone exposures and temperature extremes in the US and Europe using a composite of multidecadal datasets, fully correcting for ozone-temperature covariation. We find generally larger and more spatially varying sensitivities of all three crops to ozone exposures than are implied by experimentally derived concentration-response functions used in most previous studies. Stronger ozone tolerance is found in regions with high ozone levels and high consumptive crop water use, reflecting the existence of spatial adaptation and effect of water constraints. The spatially varying sensitivities to temperature extremes also indicate stronger heat tolerance in crops grown in warmer regions. The spatial adaptation of crops to ozone and temperature we find can serve as a surrogate for future adaptation. Using the PDLR-derived sensitivities and 2000-2050 ozone and temperature projections by the Community Earth System Model, we estimate that future warming and unmitigated ozone pollution can combine to cause an average decline in US wheat, maize and soybean production by 13%, 43% and 28%, respectively, and a smaller decline for European crops. Aggressive ozone regulation is shown to offset such decline to various extents, especially for wheat. Our findings demonstrate the importance of considering ozone regulation

  5. Modifiers of short-term effects of ozone on mortality in eastern Massachusetts - A case-crossover analysis at individual level

    Directory of Open Access Journals (Sweden)

    Schwartz Joel

    2010-01-01

    Full Text Available Abstract Background Substantial epidemiological studies demonstrate associations between exposure to ambient ozone and mortality. A few studies simply examine the modification of this ozone effect by individual characteristics and socioeconomic status, but socioeconomic status was usually coded at the city level. Methods This study used a case-crossover design to examine whether impacts of ozone on mortality were modified by socioeconomic status coded at the tract or characteristics at an individual level in eastern Massachusetts, US for a period May-September, 1995-2002, with a total of 157,197 non-accident deaths aging 35 years or older. We used moving averages of maximal 8-hour concentrations of ozone monitored at 8 stationary stations as personal exposure. Results A 10 ppb increase in the four-day moving average of maximal 8-hour ozone was associated with 1.68% (95% confidence interval (CI: 0.51%, 2.87%, 1.96% (95% CI: -1.83%, 5.90%, 8.28% (95% CI: 0.66%, 16.48%, 0.44% (95% CI: -1.45%, 2.37%, -0.83% (95% CI: -2.94%, 1.32%, -1.09% (95% CI: -4.27%, 2.19% and 6.5% (95% CI: 1.74%, 11.49% changes in all natural deaths, respiratory disorders, diabetes, cardiovascular diseases, heart diseases, acute myocardial infarction and stroke, respectively. We did not find any evidence that the associations were significantly modified by socioeconomic status or individual characteristics although small differences of estimates across subpopulations were demonstrated. Conclusions Exposure to ozone was associated with specific cause mortality in Eastern Massachusetts during May-September, 1995-2002. There was no evidence that effects of ozone on mortality were significantly modified by socioeconomic status and individual characteristics.

  6. Secondary maxima in ozone profiles

    Directory of Open Access Journals (Sweden)

    R. Lemoine

    2004-01-01

    Full Text Available Ozone profiles from balloon soundings as well as SAGEII ozone profiles were used to detect anomalous large ozone concentrations of ozone in the lower stratosphere. These secondary ozone maxima are found to be the result of differential advection of ozone-poor and ozone-rich air associated with Rossby wave breaking events. The frequency and intensity of secondary ozone maxima and their geographical distribution is presented. The occurrence and amplitude of ozone secondary maxima is connected to ozone variability and trend at Uccle and account for a large part of the total ozone and lower stratospheric ozone variability.

  7. The effect of winter stress on Ilex aquifolium L.previously fumigated with ozone

    International Nuclear Information System (INIS)

    Ranford, Jonathan; Reiling, Kevin

    2007-01-01

    European Holly (Ilex aquifolium) received either charcoal-filtered air (CFA) or CFA with 70 nl l -1 ozone added for 7 h day -1 over a 28 day period. Plants were then transferred into cooling incubators for hardening (4 o C day/2 o C night; day length 12 h) for 7 days and then to the frosting stage (2 o C day and -5, -10 or -15 o C night) for 4 days. The plants were then placed in ambient conditions. Treatment produced significant differences in chlorophyll fluorescence data. Stomatal conductance was significantly higher for the ozone treatments though both showed a general decline over all temperature regimes. Ozone also significantly increased electrolyte leakage and reduced winter survival. These results show that ambient concentrations of ozone can reduce the tolerance of I. aquifolium to freezing stress, which may have serious implications for its establishment and survival. - Exposure to ozone decreases the winter hardening capability and markedly increases the frost sensitivity of Ilex aquifolium

  8. The stratospheric ozone and the ozone layer

    International Nuclear Information System (INIS)

    Zea Mazo, Jorge Anibal; Leon Aristizabal Gloria Esperanza; Eslava Ramirez Jesus Antonio

    2000-01-01

    An overview is presented of the principal characteristics of the stratospheric ozone in the Earth's atmosphere, with particular emphasis on the tropics and the ozone hole over the poles. Some effects produced in the atmosphere as a consequence of the different human activities will be described, and some data on stratospheric ozone will be shown. We point out the existence of a nucleus of least ozone in the tropics, stretching from South America to central Africa, with annual mean values less than 240 DU, a value lower than in the middle latitudes and close to the mean values at the South Pole. The existence of such a minimum is confirmed by mean values from measurements made on satellites or with earthbound instruments, for different sectors in Colombia, like Medellin, Bogota and Leticia

  9. Ozone exposure- and flux-based response relationships with photosynthesis of winter wheat under fully open air condition.

    Science.gov (United States)

    Feng, Zhaozhong; Calatayud, Vicent; Zhu, Jianguo; Kobayashi, Kazuhiko

    2018-04-01

    Five winter wheat cultivars were exposed to ambient (A-O 3 ) and elevated (E-O 3 , 1.5 ambient) O 3 in a fully open-air fumigation system in China. Ozone exposure- and flux based response relationships were established for seven physiological variables related to photosynthesis. The performance of the fitting of the regressions in terms of R 2 increased when second order regressions instead of first order ones were used, suggesting that effects of O 3 were more pronounced towards the last developmental stages of the wheat. The more robust indicators were those related with CO 2 assimilation, Rubisco activity and RuBP regeneration capacity (A sat , J max and Vc max ), and chlorophyll content (Chl). Flux-based metrics (POD y , Phytotoxic O 3 Dose over a threshold ynmolO 3 m -2 s -1 ) predicted slightly better the responses to O 3 than exposure metrics (AOTX, Accumulated O 3 exposure over an hourly Threshold of X ppb) for most of the variables. The best performance was observed for metrics POD 1 ( A sat , J max and Vc max ) and POD 3 (Chl). For this crop, the proposed response functions could be used for O 3 risk assessment based on physiological effects and also to include the influence of O 3 on yield or other variables in models with a photosynthetic component. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Heterogeneous ozonation reactions of PAHs and fatty acid methyl esters in biodiesel particulate matter

    Science.gov (United States)

    Kasumba, John; Holmén, Britt A.

    2018-02-01

    Numerous studies have examined the oxidation of PAHs found in diesel particulate matter (PM) by ozone, but no studies have investigated the ozone oxidation of biodiesel exhaust PM. Fatty acid methyl esters (FAMEs), found in high abundance in biodiesel PM, can potentially alter the kinetics of the reactions between atmospheric oxidants such as ozone and particle-phase PAHs. In this study, the heterogeneous reactivity of 16 EPA PAHs upon 24 h exposure to 0.4 ppm ozone in the presence (PAH + FAMES) and absence (PAH-only) of FAMEs was investigated at room temperature and 50% relative humidity. The ozone-reactivity of the PAHs detected in 20% biodiesel (B20) exhaust PM was also investigated. In the absence of FAMEs, the pseudo-first order ozone reaction rate constant, kO 3 , of PAHs varied from 0.086 ± 0.030 hr-1 (chrysene) to 0.184 ± 0.078 hr-1 (anthracene). In the presence of FAMEs, kO 3 of the PAHs varied between 0.013 ± 0.012 hr-1 (benzo[b]fluoranthene) and 0.168 ± 0.028 hr-1 (benzo[a]pyrene), and with the exception of benzo[a]pyrene, the kO 3 of PAHs were 1.2-8 times lower compared to those obtained during the PAH-only ozone exposure. Only one PAH, benzo[a]pyrene (BaP), did not show a significant change in kO3 with addition of FAMEs. Phenanthrene, fluoranthene, and pyrene, the only PAHs detected in the B20 PM, had kO 3 values about 4 times lower in B20 PM than those obtained when spiked PAHs-only were exposed to ozone. The kO 3 values of phenanthrene and fluoranthene in the B20 PM were 2 times higher than rates obtained when the PAH mix was exposed to ozone in the presence of the FAMEs. In contrast, pyrene's kO 3 in the B20 PM was about 2 times lower than that obtained for the PAH + FAMEs exposure. Observed differences in PAH behavior demonstrate individual PAH heterogeneous reactivity with gas-phase ozone is sensitive to PAH (vapor pressure, solubility/sorption to matrix components, chemical reactivity) as well as substrate properties (PAH and O3 diffusivity

  11. Exposure of Norway spruce to ozone increases the sensitivity of current year needles to photoinhibition and desiccation

    DEFF Research Database (Denmark)

    Mikkelsen, Teis Nørgaard; Ro-Poulsen, H.

    1994-01-01

    decreases in net photosynthesis and chlorophyll fluorescence (FN/FM) were found during periods with co-occurrence of high ozone concentrations And high light intensities, indicating interactions between effects of ozone and photoinhibition. After termination of fumigation enhanced rates of photosynthesis...

  12. Modification of fecundity and fertility during oogenesis by γ radiation and/or ozone with a cytological analysis in the ectoparasitic wasp, Habrobracon juglandis (Ashmead)

    International Nuclear Information System (INIS)

    Ofuoku, E.E.

    1984-01-01

    In Experiment I, adult female wasps were exposed to ozone for 0, 2, 4, 6, 8, 10, 12, 16, 24, and 27 h. The results indicated that the 27 h of ozone exposure produced 100% lethality on the first day. Exposures below 27 h progressively decreased life span with increasing length of exposure. In Experiment II A, adult virgin Habrobracon females were exposed to ozone for 0, 2, 4, 6, 8, 10, 12, 16, and 24 h to determine the effects of ozone on fecundity (egg laying ability) and fertility (egg hatching ability). The results showed that ozone significantly decreased fecundity and fertility in all meiotic stages except metaphase I. In Experiment II B, adult virgin Habrobracon females were exposed to Co-60 γ radiation. All treated wasps showed significant progressive decreases in fecundity and fertility with increases in radiation dose. In Experiment II C, adult virgin Habrobracon females were exposed to Co-60 γ radiation, to ozone, or to combinations thereof to determine the effects of these insults on fecundity and fertility. Together or singly ozone and radiation reduced fecundity and fertility. In Experiment III, adult virgin Habrobracon females were exposed to the conditions of Experiment II C to correlate by cytological examination of the ovarioles the effects of ionizing radiation and/or ozone on the germ cells at specific meiotic stages. Results obtained from the cytological study explain the fecundity and fertility observations

  13. Exploration of the formation mechanism and source attribution of ambient ozone in Chongqing with an observation-based model

    Institute of Scientific and Technical Information of China (English)

    SU Rong; ZHAI ChongZhi; ZHANG YuanHang; LU KeDing; YU JiaYan; TAN ZhaoFeng; JIANG MeiQing; LI Jing; XIE ShaoDong; WU YuSheng; ZENG LiMin

    2018-01-01

    An intensive field campaign was conducted in Chongqing during the summer of 2015 to explore the formation mechanisms of ozone pollution.The sources of ozone,the local production rates,and the controlling factors,as well as key species of volatile organic compounds (VOCs),were quantified by integrating a local ozone budget analysis,calculations of the relative incremental reactivity,and an empirical kinetic model approach.It was found that the potential for rapid local ozone formation exists in Chongqing.During ozone pollution episodes,the ozone production rates were found to be high at the upwind station Nan Quan,the urban station Chao Zhan,and the downwind station Jin-Yun Shan.The average local ozone production rate was 30× 10-9 V/V h1 and the daily integration of the produced ozone was greater than 180× 10-9 V/V.High ozone concentrations were associated with urban and downwind air masses.At most sites,the local ozone production was VOC-limited and the key species were aromatics and alkene,which originated mainly from vehicles and solvent usage.In addition,the air masses at the northwestern rural sites were NOx-limited and the local ozone production rates were significantly higher during the pollution episodes due to the increased NOx concentrations.In summary,the ozone abatement strategies of Chongqing should be focused on the mitigation of VOCs.Nevertheless,a reduction in NOx is also beneficial for reducing the regional ozone peak values in Chongqing and the surrounding areas.

  14. Physiological and foliar injury responses of Prunus serotina, Fraxinus americana, and Acer rubrum seedlings to varying soil moisture and ozone

    International Nuclear Information System (INIS)

    Schaub, M.; Skelly, J.M.; Steiner, K.C.; Davis, D.D.; Pennypacker, S.P.; Zhang, J.; Ferdinand, J.A.; Savage, J.E.; Stevenson, R.E.

    2003-01-01

    High soil water availability favors ozone uptake, increases foliar injury, and exacerbates the negative ozone effect on gas exchange of seedlings of deciduous tree species. - Sixteen black cherry (Prunus serotina, Ehrh.), 10 white ash (Fraxinus americana, L.) and 10 red maple (Acer rubrum, L.) 1-year old seedlings were planted per plot in 1997 on a former nursery bed within 12 open-top chambers and six open plots. Seedlings were exposed to three different ozone scenarios (ambient air: 100% O 3 ; non-filtered air: 98% ambient O 3 ; charcoal-filtered air: 50% ambient O 3 ) within each of two different water regimes (nine plots irrigated, nine plots non-irrigated) during three growing seasons. During the 1998 and 1999 growing season, leaf gas exchange, plant water relations, and foliar injury were measured. Climatic data, ambient- and chamber-ozone-concentrations were monitored. We found that seedlings grown under irrigated conditions had similar (in 1998) but significantly higher gas exchange rates (in 1999) than seedlings grown within non-irrigated plots among similar ozone exposures. Cherry and ash had similar ozone uptake but cherry developed more ozone-induced injury (<34% affected leaf area, LAA) than ash (<5% LAA), while maple rarely showed foliar injury, indicating the species differed in ozone sensitivity. Significantly more severe injury on seedlings grown under irrigated conditions than seedlings grown under non-irrigated conditions demonstrated that soil moisture altered seedling responses to ambient ozone exposures

  15. Psidium guajava 'Paluma' (the guava plant) as a new bio-indicator of ozone in the tropics

    International Nuclear Information System (INIS)

    Furlan, C.M.; Moraes, R.M.; Bulbovas, P.; Domingos, M.; Salatino, A.; Sanz, M.J.

    2007-01-01

    Psidium guajava 'Paluma' saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF), and ambient non-filtered air + 40 ppb ozone (NF + O 3 ) 8 h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12 895 ppb h -1 , respectively for the three treatments. After 5 days of exposure (AOT40 = 1497 ppb h -1 ), interveinal red stippling appeared in plants in the NF + O 3 chamber. In the NF chamber, symptoms were observed only after 40 days of exposure (AOT40 = 880 ppb h -1 ). After 60 days, injured leaves per plant corresponded to 86% in NF + O 3 and 25% in the NF treatment, and the average leaf area injured was 45% in NF + O 3 and 5% in the NF treatment. The extent of leaf area injured (leaf injury index) was explained mainly by the accumulated exposure of ozone (r 2 = 0.91; p < 0.05). - Psidium guajava 'Paluma', a tropical species widely used in Brazilian food industry, is a potential sensitive bio-indicator of ozone

  16. Tree age dependence and within-canopy variation of leaf gas exchange and antioxidative defence in Fagus sylvatica under experimental free-air ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Herbinger, K. [Institut fuer Pflanzenwissenschaften, Universitaet Graz, Schubertstrasse 51, A-8010 Graz (Austria)]. E-mail: karin.herbinger@uni-graz.at; Then, Ch. [Bundesamt und Forschungszentrum fuer Wald, Abteilung Forstpflanzenphysiologie, Rennweg 1, A-6020 Innsbruck (Austria)]|[Lehrstuhl fuer Oekophysiologie der Pflanzen, Technische Universitaet Muenchen, Life Sciences Center Weihenstephan, Am Hochanger 13, D-85354 Freising (Germany); Loew, M.; Koch, N. [Lehrstuhl fuer Oekophysiologie der Pflanzen, Technische Universitaet Muenchen, Life Sciences Center Weihenstephan, Am Hochanger 13, D-85354 Freising (Germany); Haberer, K.; Alexous, M. [Institut fuer Forstbotanik und Baumphysiologie, Universitaet Freiburg, Georges-Koehler-Allee 053/054, D-79085 Freiburg (Germany); Remele, K. [Institut fuer Pflanzenwissenschaften, Universitaet Graz, Schubertstrasse 51, A-8010 Graz (Austria); Heerdt, C. [Lehrstuhl fuer Bioklimatologie und Immissionsforschung, Technische Universitaet Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Grill, D. [Institut fuer Pflanzenwissenschaften, Universitaet Graz, Schubertstrasse 51, A-8010 Graz (Austria); Rennenberg, H. [Institut fuer Forstbotanik und Baumphysiologie, Universitaet Freiburg, Georges-Koehler-Allee 053/054, D-79085 Freiburg (Germany); Haeberle, K.-H.; Matyssek, R. [Lehrstuhl fuer Oekophysiologie der Pflanzen, Technische Universitaet Muenchen, Life Sciences Center Weihenstephan, Am Hochanger 13, D-85354 Freising (Germany); Tausz, M. [Institut fuer Pflanzenwissenschaften, Universitaet Graz, Schubertstrasse 51, A-8010 Graz (Austria)]|[[School of Forest and Ecosystem Science, University of Melbourne, Water Street, Creswick, Vic. 3363 (Australia); Wieser, G. [Bundesamt und Forschungszentrum fuer Wald, Abteilung Forstpflanzenphysiologie, Rennweg 1, A-6020 Innsbruck (Austria)

    2005-10-15

    We characterized leaf gas exchange and antioxidative defence of two-year-old seedlings and 60-year-old trees of Fagus sylvatica exposed to ambient (1xO{sub 3}) or two-fold ambient (2xO{sub 3}) O{sub 3} concentrations (maximum of 150 ppb) in a free-air canopy exposure system throughout the growing season. Decline in photosynthesis from sun-exposed to shaded conditions was more pronounced in adult than juvenile trees. Seedling leaves and leaves in the sun-exposed canopy had higher stomatal conductance and higher internal CO{sub 2} concentrations relative to leaves of adult trees and leaves in shaded conditions. There was a weak overall depression of photosynthesis in the 2xO{sub 3} variants across age classes and canopy positions. Pigment and tocopherol concentrations of leaves were significantly affected by canopy position and tree age, whereas differences between 1xO{sub 3} and 2xO{sub 3} regimes were not observed. Glutathione concentrations were significantly increased under 2xO{sub 3} across both age classes and canopy levels. Seedlings differed from adult trees in relevant physiological and biochemical traits in ozone response. The water-soluble antioxidative systems responded most sensitively to 2xO{sub 3} without regard of tree age or canopy position. - Ozone effects on leaf gas exchange and antioxidative systems of beech across tree age and canopy level were investigated in a free air exposure system.

  17. Fractal and variability analysis of simulations in ozone level due to oxides of nitrogen and sulphur

    Science.gov (United States)

    Bhardwaj, Rashmi; Pruthi, Dimple

    2017-10-01

    Air pollution refers to the release of pollutants into the air. These pollutants are detrimental to human the planet as a whole. Apart from causing respiratory infections and pulmonary disorders, rising levels of Nitrogen Dioxide is worsening ozone pollution. Formation of Ground-level ozone involves nitrogen oxides and volatile gases in the sunlight. Volatile gases are emitted from vehicles primarily. Ozone is harmful gas and its exposure can trigger serious health effects as it damages lung tissues. In order to decrease the level of ozone, level of oxides leading to ozone formation has to be dealt with. This paper deals with the simulations in ozone due to oxides of nitrogen and sulphur. The data from Central Pollution Control Board shows positive correlation for ozone with oxides of sulphur and nitrogen for RK Puram, Delhi in India where high concentration of ozone has been found. The correlation between ozone and sulphur, nitrogen oxides is moderate during summer while weak during winters. Ozone with nitrogen and sulphur dioxide follow persistent behavior as Hurst exponent is between 0.5 and 1. The fractal dimension for Sulphur dioxide is 1.4957 indicating the Brownian motion. The behavior of ozone is unpredictable as index of predictability is close to zero.

  18. Determination of total ozone from DMSP multichannel filter radiometer measurements

    International Nuclear Information System (INIS)

    Luther, F.M.; Weichel, R.L.

    1992-01-01

    The multichannel filter radiometer (MFR) infrared sensor was first flown in 1977 on a Defense Meteorological Satellite Program (DMSP) Block 5D series satellite operated by the US Air Force. The first four satellites in this series carried MFR sensors from which total atmospheric column ozone amounts may be derived. The MFR sensor was the first cross-track scanning sensor capable of measuring ozone. MFR sensor infrared measurements are taken day and night. The satellites are in polar sun-synchronous orbits providing daily global coverage. The series of four sensors spans a data period of nearly three years. The MFR sensor measures infrared radiances for 16 channels. Total ozone amounts are determined from sets of radiance measurements using an empirical relationship that is developed using linear regression analysis. Total ozone is modeled as a linear combination of terms involving functions of the MFR radiances for four channels (1, 3, 7 and 16) and the secant of the zenith angle. The MFR scans side to side in discrete steps of 40. The MFR sensor takes infrared radiance measurements at 25 cross-track scanning locations every 32 seconds. The instrument could take a theoretical maximum of 67,500 measurements per day, although typically 35,000 - 45,000 measurements are taken per day

  19. The effects of welding parameters on ultra-violet light emissions, ozone and CrVI formation in MIG welding.

    Science.gov (United States)

    Dennis, J H; Mortazavi, S B; French, M J; Hewitt, P J; Redding, C R

    1997-01-01

    This paper describes the relationships between ultra-violet emission, ozone generation and CrVI production in MIG welding which were measured as a function of shield gas flow rate, welding voltage, electrode stick-out and shield gas composition using an automatic welding rig that permitted MIG welding under reproducible conditions. The experimental results are interpreted in terms of the physico-chemical processes occurring in the micro- and macro-environments of the arc as part of research into process modification to reduce occupational exposure to ozone and CrVI production rates in MIG welding. We believe the techniques described here, and in particular the use of what we have termed u.v.-ozone measurements, will prove useful in further study of ozone generation and CrVI formation and may be applied in the investigation of engineering control of occupational exposure in MIG and other welding process such as Manual Metal Arc (MMA) and Tungsten Inert Gas (TIG).

  20. Ozone effects on Sphagnum mosses, carbon dioxide exchange and methane emission in boreal peatland microcosms

    International Nuclear Information System (INIS)

    Niemi, Riikka; Holopainen, Toini; Martikainen, Pertti J.; Silvola, Jouko

    2002-01-01

    Microcosms of a boreal peatland originating from an oligotrophic fen in Eastern Finland were fumigated under four ozone concentrations (0, 50, 100 and 150 ppb O 3 ) in laboratory growth chambers during two separate experiments (autumn and summer) for 4 and 6 weeks, respectively. Ozone effects on Sphagnum mosses and the fluxes of carbon dioxide and methane were evaluated. In both experiments, the three Sphagnum species studied showed only a few significant responses to ozone. In the autumn experiment, membrane permeability of S. angustifolium, measured as conductivity and magnesium leakage, was significantly higher under ozone fumigation (P=0.005 and 2 exchange during the 6-week-long summer experiment, but dark ecosystem respiration was transiently increased by ozone concentration of 100 ppb after 14 days of exposure (P<0.05). Fumigation with 100 ppb of ozone, however, more than doubled (P<0.05) methane emission from the peatland monoliths. Our results suggest that increasing tropospheric ozone concentration may cause substantial changes in the carbon gas cycling of boreal peatlands, even though these changes are not closely associated with the changes in Sphagnum vegetation

  1. Ozone and NOx chemistry in the eastern US: evaluation of CMAQ/CB05 with satellite (OMI data

    Directory of Open Access Journals (Sweden)

    T. P. Canty

    2015-10-01

    Full Text Available Regulatory air quality models, such as the Community Multiscale Air Quality model (CMAQ, are used by federal and state agencies to guide policy decisions that determine how to best achieve adherence with National Ambient Air Quality Standards for surface ozone. We use observations of ozone and its important precursor NO2 to test the representation of the photochemistry and emission of ozone precursors within CMAQ. Observations of tropospheric column NO2 from the Ozone Monitoring Instrument (OMI, retrieved by two independent groups, show that the model overestimates urban NO2 and underestimates rural NO2 under all conditions examined for July and August 2011 in the US Northeast. The overestimate of the urban to rural ratio of tropospheric column NO2 for this baseline run of CMAQ (CB05 mechanism, mobile NOx emissions from the National Emissions Inventory; isoprene emissions from MEGAN v2.04 suggests this model may underestimate the importance of interstate transport of NOx. This CMAQ simulation leads to a considerable overestimate of the 2-month average of 8 h daily maximum surface ozone in the US Northeast, as well as an overestimate of 8 h ozone at AQS sites during days when the state of Maryland experienced NAAQS exceedances. We have implemented three changes within CMAQ motivated by OMI NO2 as well as aircraft observations obtained in July 2011 during the NASA DISCOVER-AQ campaign: (a the modeled lifetime of organic nitrates within CB05 has been reduced by a factor of 10, (b emissions of NOx from mobile sources has been reduced by a factor of 2, and (c isoprene emissions have been reduced by using MEGAN v2.10 rather than v2.04. Compared to the baseline simulation, the CMAQ run using all three of these changes leads to considerably better simulation of column NO2 in both urban and rural areas, better agreement with the 2-month average of daily 8 h maximum ozone in the US Northeast, fewer number of false positives of an ozone exceedance

  2. Pollen exposure and hospitalization due to asthma exacerbations: daily time series in a European city

    Science.gov (United States)

    Osborne, Nicholas J.; Alcock, Ian; Wheeler, Benedict W.; Hajat, Shakoor; Sarran, Christophe; Clewlow, Yolanda; McInnes, Rachel N.; Hemming, Deborah; White, Mathew; Vardoulakis, Sotiris; Fleming, Lora E.

    2017-10-01

    Exposure to pollen can contribute to increased hospital admissions for asthma exacerbation. This study applied an ecological time series analysis to examine associations between atmospheric concentrations of different pollen types and the risk of hospitalization for asthma in London from 2005 to 2011. The analysis examined short-term associations between daily pollen counts and hospital admissions in the presence of seasonal and long-term patterns, and allowed for time lags between exposure and admission. Models were adjusted for temperature, precipitation, humidity, day of week, and air pollutants. Analyses revealed an association between daily counts (continuous) of grass pollen and adult hospital admissions for asthma in London, with a 4-5-day lag. When grass pollen concentrations were categorized into Met Office pollen `alert' levels, `very high' days (vs. `low') were associated with increased admissions 2-5 days later, peaking at an incidence rate ratio of 1.46 (95%, CI 1.20-1.78) at 3 days. Increased admissions were also associated with `high' versus `low' pollen days at a 3-day lag. Results from tree pollen models were inconclusive and likely to have been affected by the shorter pollen seasons and consequent limited number of observation days with higher tree pollen concentrations. Future reductions in asthma hospitalizations may be achieved by better understanding of environmental risks, informing improved alert systems and supporting patients to take preventive measures.

  3. Earth's ozone layer

    International Nuclear Information System (INIS)

    Lasa, J.

    1991-01-01

    The paper contain the actual results of investigations of the influence of the human activity on the Earth's ozone layer. History of the ozone measurements and of the changes in its concentrations within the last few years are given. The influence of the trace gases on both local and global ozone concentrations are discussed. The probable changes of the ozone concentrations are presented on the basis of the modelling investigations. The effect of a decrease in global ozone concentration on human health and on biosphere are also presented. (author). 33 refs, 36 figs, 5 tabs

  4. Urban Summertime Ozone of China: Peak Ozone Hour and Nighttime Mixing

    Science.gov (United States)

    Qu, H.; Wang, Y.; Zhang, R.

    2017-12-01

    We investigate the observed diurnal cycle of summertime ozone in the cities of China using a regional chemical transport model. The simulated daytime ozone is in general agreement with the observations. Model simulations suggest that the ozone peak time and peak concentration are a function of NOx (NO + NO2) and volatile organic compound (VOC) emissions. The differences between simulated and observed ozone peak time and peak concentration in some regions can be applied to understand biases in the emission inventories. For example, the VOCs emissions are underestimated over the Pearl River Delta (PRD) region, and either NOx emissions are underestimated or VOC emissions are overestimated over the Yangtze River Delta (YRD) regions. In contrast to the general good daytime ozone simulations, the simulated nighttime ozone has a large low bias of up to 40 ppbv. Nighttime ozone in urban areas is sensitive to the nocturnal boundary-layer mixing, and enhanced nighttime mixing (from the surface to 200-500 m) is necessary for the model to reproduce the observed level of ozone.

  5. The effect of increased ozone concentrations in the air on selected aspects of rat reproduction.

    Science.gov (United States)

    Jedlińska-Krakowska, M; Gizejewski, Z; Dietrich, G J; Jakubowski, K; Glogowski, J; Penkowski, A

    2006-01-01

    Five-month-old male rates were exposed to 0.5 ppm ozone for 50 days, 5 hours a day. A week before the completion of ozone exposure, a biological test was performed to determine the fertilization rate and the survival rate of newborns in both ozone-exposed and control animals. After 50 days, the rats were sacrificed with an overdose of halotane, and testes were collected to assess the morphology and motility of spermatozoa. Neither the morphology of spermatozoa nor motility parameters determined by the CASA (computer-assisted sperm analysis) system showed statistically significant differences between ozone-exposed and control males. The number of successful matings and the survival rate of newborns per litter within one year postpartum were also similar in both groups. However, sperm concentration was by 17% lower in ozone-exposed rats, compared with the control animals.

  6. Total ozone changes in the 1987 Antarctic ozone hole

    Science.gov (United States)

    Krueger, Arlin J.; Schoeberl, Mark R.; Doiron, Scott D.; Sechrist, Frank; Galimore, Reginald

    1988-01-01

    The development of the Antarctic ozone minimum was observed in 1987 with the Nimbus 7 Total Ozone Mapping Spectrometer (TOMS) instrument. In the first half of August the near-polar (60 and 70 deg S) ozone levels were similar to those of recent years. By September, however, the ozone at 70 and 80 deg S was clearly lower than any previous year including 1985, the prior record low year. The levels continued to decrease throughout September until October 5 when a new record low of 109 DU was established at a point near the South Pole. This value is 29 DU less than the lowest observed in 1985 and 48 DU less than the 1986 low. The zonal mean total ozone at 60 deg S remained constant throughout the time of ozone hole formation. The ozone decline was punctuated by local minima formed away from the polar night boundary at about 75 deg S. The first of these, on August 15 to 17, formed just east of the Palmer Peninsula and appears to be a mountain wave. The second major minimum formed on September 5 to 7 again downwind of the Palmer Peninsula. This event was larger in scale than the August minimum and initiated the decline of ozone across the polar region. The 1987 ozone hole was nearly circular and pole centered for its entire life. In previous years the hole was perturbed by intrusions of the circumpolar maximum into the polar regions, thus causing the hole to be elliptical. The 1987 hole also remained in place until the end of November, a few days longer than in 1985, and this persistence resulted in the latest time for recovery to normal values yet observed.

  7. Physiological effects of ozone on cultivars of watermelon (Citrullus lanatus) and muskmelon (Cucumis melo) widely grown in Spain.

    Science.gov (United States)

    Fernandez-Bayon, J M; Barnes, J D; Ollerenshaw, J H; Davison, A W

    1993-01-01

    Two cultivars of watermelon (Citrullus lanatus) and muskmelon (Cucumis melo), which are widely grown in Spain, were exposed to ozone (70 nl litre(-1), 6 h d(-1)) for 21 days. Ozone sensitivity was assessed by recording the extent of visible injury, changes in fast-fluorescence kinetics, the relative-growth rate (R) of root (RR) and shoot (RS), and effects on the number of flowers produced per plant. Leaf gas exchange was measured in order to provide some indication of the factors underlying differential response to ozone. After 9-10 days of fumigation, all the cultivars developed typical visible symptoms of zone injury on the older leaves. However, significant (P watermelon, there was a marked reduction in the rate of CO(2) assimilation as a result of exposure to ozone, and this was accompanied by a parallel decrease in stomatal conductance. Mean plant-relative-growth rate (R) was markedly (P watermelon, but there were no significant effects on R in muskmelon. Ozone reduced root growth relative to the shoot in three out of four cultivars-an effect that may be of considerable ecological significance. Moreover, exposure to ozone reduced flower production in both muskmelon and watermelon, which indicated effects on yield. There was no correlation between a variety of methods used to assess ozone sensitivity and visible injury, and reasons for this are discussed. This observation draws clear attention to the dangers in ranking plants for ozone sensitivity purely on the basis of visible symptoms. It is concluded from this study that ozone-insensitive genotypes should be identified and considered for planting in the major areas of melon production concentrated on the Mediterranean coast of Spain.

  8. Ozone modeling

    International Nuclear Information System (INIS)

    McIllvaine, C.M.

    1994-01-01

    Exhaust gases from power plants that burn fossil fuels contain concentrations of sulfur dioxide (SO 2 ), nitric oxide (NO), particulate matter, hydrocarbon compounds and trace metals. Estimated emissions from the operation of a hypothetical 500 MW coal-fired power plant are given. Ozone is considered a secondary pollutant, since it is not emitted directly into the atmosphere but is formed from other air pollutants, specifically, nitrogen oxides (NO), and non-methane organic compounds (NMOQ) in the presence of sunlight. (NMOC are sometimes referred to as hydrocarbons, HC, or volatile organic compounds, VOC, and they may or may not include methane). Additionally, ozone formation Alternative is a function of the ratio of NMOC concentrations to NO x concentrations. A typical ozone isopleth is shown, generated with the Empirical Kinetic Modeling Approach (EKMA) option of the Environmental Protection Agency's (EPA) Ozone Isopleth Plotting Mechanism (OZIPM-4) model. Ozone isopleth diagrams, originally generated with smog chamber data, are more commonly generated with photochemical reaction mechanisms and tested against smog chamber data. The shape of the isopleth curves is a function of the region (i.e. background conditions) where ozone concentrations are simulated. The location of an ozone concentration on the isopleth diagram is defined by the ratio of NMOC and NO x coordinates of the point, known as the NMOC/NO x ratio. Results obtained by the described model are presented

  9. Ultraviolet-ozone treatment reduces levels of disease-associated prion protein and prion infectivity

    Science.gov (United States)

    Johnson, C.J.; Gilbert, P.; McKenzie, D.; Pedersen, J.A.; Aiken, Judd M.

    2009-01-01

    Background. Transmissible spongiform encephalopathies (TSEs) are a group of fatal neurodegenerative diseases caused by novel infectious agents referred to as prions. Prions appear to be composed primarily, if not exclusively, of a misfolded isoform of the cellular prion protein. TSE infectivity is remarkably stable and can resist many aggressive decontamination procedures, increasing human, livestock and wildlife exposure to TSEs. Findings. We tested the hypothesis that UV-ozone treatment reduces levels of the pathogenic prion protein and inactivates the infectious agent. We found that UV-ozone treatment decreased the carbon and prion protein content in infected brain homogenate to levels undetectable by dry-ashing carbon analysis or immunoblotting, respectively. After 8 weeks of ashing, UV-ozone treatment reduced the infectious titer of treated material by a factor of at least 105. A small amount of infectivity, however, persisted despite UV-ozone treatment. When bound to either montmorillonite clay or quartz surfaces, PrPTSE was still susceptible to degradation by UV-ozone. Conclusion. Our findings strongly suggest that UV-ozone treatment can degrade pathogenic prion protein and inactivate prions, even when the agent is associated with surfaces. Using larger UV-ozone doses or combining UV-ozone treatment with other decontaminant methods may allow the sterilization of TSE-contaminated materials. ?? 2009 Aiken et al; licensee BioMed Central Ltd.

  10. The exhibition to ozone diminishes the adherence and increases the membrane permeability of macrophages alveolar of rate

    International Nuclear Information System (INIS)

    Garcia, J.

    2000-01-01

    Ozone gas is generated photochemically in areas with high levels of automotive or industrial emissions, and causes irritation and inflammation of the airways if inhaled. Rat alveolar macrophages were obtained by lung lavage from male Sprague Dawley rats and used as a model to assess ozone induced cell damage (0,594 ppm for up to 60 minutes). Ozone exposure caused loss of cell adherence to a polystyrene substrate and increased membrane permeability, as noted by increases in specific 51 Cr release and citoplasmic calcium levels. The results indicate that the cell membrane is a target for ozone damage. Elevations of cytoplasmic calcium could mediate other macrophage responses to ozone , including eicosanoid and nitric oxide production, with concomitant decreases in phagocytic ability and superoxide production. (Author) [es

  11. PM2.5 and tropospheric ozone in China: overview of situation and responses

    Science.gov (United States)

    Zhang, Hua

    This work reviewed the observational status of PM2.5 and tropospheric ozone in China. It told us the observational facts on the ratios of typical types of aerosol components to the total PM2.5/PM10, and daily and seasonal change of near surface ozone concentration at different cities of China; the global concentration distribution of tropospheric ozone observed by satellite in 2010-2013 was also given for comparison; the PM2.5 concentration distribution and their seasonal change in China region were simulated by an aerosol chemistry-global climate modeling system. Different contribution from five kinds of aerosols to the simulated PM2.5 was analyzed. Then, it linked the emissions of aerosol and greenhouse gases and their radiative forcing and thus gave their climatic effect by reducing their emissions on the basis of most recently published IPCC AR5. Finally it suggested policies on reducing emissions of short-lived climate pollutants (SLCPs) (such as PM2.5 and tropospheric ozone) in China from protecting both climate and environment.

  12. Mortality tradeoff between air quality and skin cancer from changes in stratospheric ozone

    Science.gov (United States)

    Eastham, Sebastian D.; Keith, David W.; Barrett, Steven R. H.

    2018-03-01

    Skin cancer mortality resulting from stratospheric ozone depletion has been widely studied. Similarly, there is a deep body of literature on surface ozone and its health impacts, with modeling and observational studies demonstrating that surface ozone concentrations can be increased when stratospheric air mixes to the Earth’s surface. We offer the first quantitative estimate of the trade-off between these two effects, comparing surface air quality benefits and UV-related harms from stratospheric ozone depletion. Applying an idealized ozone loss term in the stratosphere of a chemistry-transport model for modern-day conditions, we find that each Dobson unit of stratospheric ozone depletion results in a net decrease in the global annual mortality rate of ~40 premature deaths per billion population (d/bn/DU). The impacts are spatially heterogeneous in sign and magnitude, composed of a reduction in premature mortality rate due to ozone exposure of ~80 d/bn/DU concentrated in Southeast Asia, and an increase in skin cancer mortality rate of ~40 d/bn/DU, mostly in Western Europe. This is the first study to quantify air quality benefits of stratospheric ozone depletion, and the first to find that marginal decreases in stratospheric ozone around modern-day values could result in a net reduction in global mortality due to competing health impact pathways. This result, which is subject to significant methodological uncertainty, highlights the need to understand the health and environmental trade-offs involved in policy decisions regarding anthropogenic influences on ozone chemistry over the 21st century.

  13. Ozone time scale decomposition and trend assessment from surface observations

    Science.gov (United States)

    Boleti, Eirini; Hueglin, Christoph; Takahama, Satoshi

    2017-04-01

    Emissions of ozone precursors have been regulated in Europe since around 1990 with control measures primarily targeting to industries and traffic. In order to understand how these measures have affected air quality, it is now important to investigate concentrations of tropospheric ozone in different types of environments, based on their NOx burden, and in different geographic regions. In this study, we analyze high quality data sets for Switzerland (NABEL network) and whole Europe (AirBase) for the last 25 years to calculate long-term trends of ozone concentrations. A sophisticated time scale decomposition method, called the Ensemble Empirical Mode Decomposition (EEMD) (Huang,1998;Wu,2009), is used for decomposition of the different time scales of the variation of ozone, namely the long-term trend, seasonal and short-term variability. This allows subtraction of the seasonal pattern of ozone from the observations and estimation of long-term changes of ozone concentrations with lower uncertainty ranges compared to typical methodologies used. We observe that, despite the implementation of regulations, for most of the measurement sites ozone daily mean values have been increasing until around mid-2000s. Afterwards, we observe a decline or a leveling off in the concentrations; certainly a late effect of limitations in ozone precursor emissions. On the other hand, the peak ozone concentrations have been decreasing for almost all regions. The evolution in the trend exhibits some differences between the different types of measurement. In addition, ozone is known to be strongly affected by meteorology. In the applied approach, some of the meteorological effects are already captured by the seasonal signal and already removed in the de-seasonalized ozone time series. For adjustment of the influence of meteorology on the higher frequency ozone variation, a statistical approach based on Generalized Additive Models (GAM) (Hastie,1990;Wood,2006), which corrects for meteorological

  14. Modeling Stomatal Conductance to Estimate Seasonal Uptake in the Ozone-Sensitive Bioindicator Plant Common Milkweed (A. syriaca L.)

    Science.gov (United States)

    Bergweiler, C.

    2008-12-01

    The US EPA National Ambient Air Quality Standard (NAAQS) was not conceived to nor does it provide an accurate definition of the absorbed ozone dose or baseline exposure level to protect vegetation. This research presents a multiplicative modeling approach based not only on atmospheric, but on equally important physiological, phenological, and environmental parameters. Physiological constraints on ozone uptake demonstrate that actual absorption is substantially lower than that assumed by a simple interpretation of hourly atmospheric ozone concentrations. Coupled with development of foliar injury expression this provides evidence that tropospheric ozone is more toxic to vegetation than is currently understood.

  15. Total Ozone Data From a European Network 1951-1957

    Science.gov (United States)

    Brönnimann, S.; Brönnimann, S.; Farmer, S.

    2001-12-01

    Soon after its foundation in 1948, the International Ozone Commission (IOC) established a total ozone network in Europe, together with the Gassiot Committee of the Royal Socitey, UNESCO, the London Meteorological Office and national services. The network was built-up in 1950 with Dobson spectrophotometers equipped with photomultipliers, which were calibrated in Oxford before shipping to the stations. In 1957, some of the stations became part of the network of the IGY, and these data can be found today at the WOUDC. The earlier data were compiled and archived in Oxford by the secretary of the IOC, Charles Normand, but have never been published and only rarely appeared in the scientific literature [Normand, QJRMS 67 (1951) 474 and QJRMS 69 (1953) 39]. The copies of the data sheets stored at UK Met Office [MO/19/3/9 Part I] comprise daily values from the following stations/time periods: Aarhus (DK, 6/52-12/59, Dobson #41), Aldergrove (UK, 6/52-4/57, #35?), Arosa (CH, 6/52-12/58 #15), Cagliari/Elmas (IT, 12/54-5/59, #48), Camborne (UK, 1/52-12/59, #32), Eskdalemuir (UK, 9/57-12/59, #35), Hemsby (UK, 6/52-9/55), Lerwick (UK, 6/52-12/59, #7), Magny les Hameaux (FR, 1/55-9/57, #49?), Messina (IT, 7/54-6/58, #46), Oxford (UK, 6/52-12/59, #1), Paris/Montsouris (FR, 10/57-8/58, #49), Reykjavik (IS, 6/52-10/59, #50), Rome/Vigna di Valle (IT, 4/54-12/59 #47), Santa Maria/Azores (ES, 2/53-7/56, #13), Spitzbergen (NO, 11/50-7/58, #8), Tromsoe (NO, 6/52-5/59, #14), Uccle (BE, 6/52-12/58, #40), and Uppsala (SE, 6/52-12/58, #30). These data could be useful to supplement the currently available total ozone measurement series. Together with existing meteorological data, they enable us to study the relation between atmospheric circulation and total ozone in a chemically largely unperturbed time period. The daily values from 1951 to 1957 have now been digitized. Using appropriate statistical methods, the quality of each series will be addressed. The data will be homogenized and re

  16. Tetracycline degradation by ozonation in the aqueous phase: Proposed degradation intermediates and pathway

    International Nuclear Information System (INIS)

    Khan, M. Hammad; Bae, Hyokwan; Jung, Jin-Young

    2010-01-01

    During the ozonation of tetracycline (TC) in aqueous media at pHs 2.2 and 7.0, the effects of pH variations, protonation and dissociation of functional groups and variation in free radical exposure were investigated to elucidate the transformation pathway. Liquid chromatography-triple quadrupole mass spectrometry detected around 15 ozonation products, and uncovered their production and subsequent degradation patterns. During ozonation at pH 2.2, the TC degradation pathway was proposed on the basis of the structure, ozonation chemistry and mass spectrometry data of TC. Ozonation of TC at the C11a-C12 and C2-C3 double bonds, aromatic ring and amino group generated products of m/z 461, 477, 509 and 416, respectively. Further ozonation at the above mentioned sites gave products of m/z 432, 480, 448, 525 and 496. The removal of TOC reached a maximum of ∼40% after 2 h of ozonation, while TC was completely removed within 4-6 min at both pHs. The low TOC removal efficiency might be due to the generation of recalcitrant products and the low ozone supply for high TC concentration. Ozonation decreased the acute toxicity of TC faster at pH 7.0 than pH 2.2, but the maximum decrease was only about 40% at both pHs after 2 h of ozonation. In this study, attempts were made to understand the correlation between the transformation products, pathway, acute toxicity and quantity of residual organics in solution. Overall, ozonation was found to be a promising process for removing TC and the products initially generated.

  17. Sulfur dioxide emissions from Peruvian copper smelters detected by the ozone monitoring instrument

    NARCIS (Netherlands)

    Carn, S.A.; Krueger, A.J.; Krotkov, N.A.; Yang, Kai; Levelt, P.F.

    2007-01-01

    We report the first daily observations of sulfur dioxide (SO2) emissions from copper smelters by a satellite-borne sensor - the Ozone Monitoring Instrument (OMI) on NASA's EOS/Aura spacecraft. Emissions from two Peruvian smelters (La Oroya and Ilo) were detected in up to 80% of OMI overpasses

  18. Influences of serum from ozone-exposed pregnant rats in an in vitro model of implantation

    Science.gov (United States)

    In our previous studies, ozone (O3) exposure during implantation [gestational day (GD) 5 and 6)] in rats resulted in intrauterine growth restriction (IUGR), suggesting impairment of implantation with exposure. The aim of this study was to (1) determine if serum collected from pre...

  19. Laboratory measurement of secondary pollutant yields from ozone reaction with HVAC filters

    International Nuclear Information System (INIS)

    Destaillats, Hugo; Chen, Wenhao; Apte, Michael; Li, Nuan; Spears, Michael; Almosni, Jeremie; Zhang, Jianshun Jensen; Fisk, William J.

    2009-01-01

    We used Proton Transfer Reaction - Mass Spectrometry (PTR-MS) and conventional sampling methods to monitor and identify trace level organic pollutants formed in heterogeneous reactions between ozone and HVAC filters in real time. Experiments were carried out using a bench-scale flow tube reactor operating with dry air and humidified air (50% RH), at realistically high ozone concentrations (150 ppbv). We explored different filter media (i.e., fiberglass and cotton/polyester blends) and different particle loadings (i.e., clean filter and filters loaded with particles for 3 months at the Lawrence Berkeley National Laboratory and the Port of Oakland, CA). Detailed emission dynamics of very low levels of certain organic pollutants from filter media upon ozone exposure in the presence of moisture have been obtained and analyzed.

  20. Betel quid chewing as a source of manganese exposure: total daily intake of manganese in a Bangladeshi population.

    Science.gov (United States)

    Al-Rmalli, Shaban W; Jenkins, Richard O; Haris, Parvez I

    2011-02-07

    A relationship between betel quid chewing in Bangladeshi populations and the development of skin lesions and tremor has been previously reported, for people exposed to high levels of arsenic (As) through drinking contaminated groundwater. Exposure to manganese (Mn) is also known to induce neurotoxicity and levels of Mn in Bangladeshi groundwater are also high. The present study evaluates betel quid chewing as an overlooked source of Mn exposure in a Bangladeshi population. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine (1) urinary Mn levels for 15 chewers and 22 non-chewers from the ethnic Bangladeshi community in the United Kingdom, and (2) Mn levels in betel quids, its individual components and other Bangladeshi foods. Betel quid chewers displayed a significantly higher (P = 0.009) mean Mn concentration in urine (1.93 μg L(-1)) compared to non-chewers (0.62 μg L(-1)). High levels of Mn were detected in Piper betel leaves with an overall average of 135 mg kg(-1) (range 26 -518 mg kg(-1)). The mean concentration of Mn in betel quid was 41 mg kg(-1) (SD 27) and the daily intake of Mn in the Bangladeshi population was estimated to be 20.3 mg/day. Chewing six betel quids could contribute up to 18% of the maximum recommended daily intake of Mn. We have demonstrated that Mn in betel quids is an overlooked source of exposure to Mn in humans. Chewers display a 3.1 fold increased urinary Mn concentration compared to non-chewers. The practice of betel quid chewing contributes a high proportion of the maximum recommended daily intake of Mn, which could make chewers in Bangladesh more vulnerable to Mn neurotoxicity.

  1. The Influence of Puff Characteristics, Nicotine Dependence, and Rate of Nicotine Metabolism on Daily Nicotine Exposure in African American Smokers.

    Science.gov (United States)

    Ross, Kathryn C; Dempsey, Delia A; St Helen, Gideon; Delucchi, Kevin; Benowitz, Neal L

    2016-06-01

    African American (AA) smokers experience greater tobacco-related disease burden than Whites, despite smoking fewer cigarettes per day (CPD). Understanding factors that influence daily nicotine intake in AA smokers is an important step toward decreasing tobacco-related health disparities. One factor of interest is smoking topography, or the study of puffing behavior. (i) to create a model using puff characteristics, nicotine dependence, and nicotine metabolism to predict daily nicotine exposure, and (ii) to compare puff characteristics and nicotine intake from two cigarettes smoked at different times to ensure the reliability of the puff characteristics included in our model. Sixty AA smokers smoked their preferred brand of cigarette at two time points through a topography device. Plasma nicotine, expired CO, and changes in subjective measures were measured before and after each cigarette. Total nicotine equivalents (TNE) was measured from 24-hour urine collected during ad libitum smoking. In a model predicting daily nicotine exposure, total puff volume, CPD, sex, and menthol status were significant predictors (R(2) = 0.44, P smokers. Cancer Epidemiol Biomarkers Prev; 25(6); 936-43. ©2016 AACR. ©2016 American Association for Cancer Research.

  2. Ozone modeling

    Energy Technology Data Exchange (ETDEWEB)

    McIllvaine, C M

    1994-07-01

    Exhaust gases from power plants that burn fossil fuels contain concentrations of sulfur dioxide (SO{sub 2}), nitric oxide (NO), particulate matter, hydrocarbon compounds and trace metals. Estimated emissions from the operation of a hypothetical 500 MW coal-fired power plant are given. Ozone is considered a secondary pollutant, since it is not emitted directly into the atmosphere but is formed from other air pollutants, specifically, nitrogen oxides (NO), and non-methane organic compounds (NMOQ) in the presence of sunlight. (NMOC are sometimes referred to as hydrocarbons, HC, or volatile organic compounds, VOC, and they may or may not include methane). Additionally, ozone formation Alternative is a function of the ratio of NMOC concentrations to NO{sub x} concentrations. A typical ozone isopleth is shown, generated with the Empirical Kinetic Modeling Approach (EKMA) option of the Environmental Protection Agency's (EPA) Ozone Isopleth Plotting Mechanism (OZIPM-4) model. Ozone isopleth diagrams, originally generated with smog chamber data, are more commonly generated with photochemical reaction mechanisms and tested against smog chamber data. The shape of the isopleth curves is a function of the region (i.e. background conditions) where ozone concentrations are simulated. The location of an ozone concentration on the isopleth diagram is defined by the ratio of NMOC and NO{sub x} coordinates of the point, known as the NMOC/NO{sub x} ratio. Results obtained by the described model are presented.

  3. Regionalization based on spatial and seasonal variation in ground-level ozone concentrations across China.

    Science.gov (United States)

    Cheng, Linjun; Wang, Shuai; Gong, Zhengyu; Li, Hong; Yang, Qi; Wang, Yeyao

    2018-05-01

    Owing to the vast territory of China and strong regional characteristic of ozone pollution, it's desirable for policy makers to have a targeted and prioritized regulation and ozone pollution control strategy in China based on scientific evidences. It's important to assess its current pollution status as well as spatial and temporal variation patterns across China. Recent advances of national monitoring networks provide an opportunity to insight the actions of ozone pollution. Here, we present rotated empirical orthogonal function (REOF) analysis that was used on studying the spatiotemporal characteristics of daily ozone concentrations. Based on results of REOF analysis in pollution seasons for 3years' observations, twelve regions with clear patterns were identified in China. The patterns of temporal variation of ozone in each region were separated well and different from each other, reflecting local meteorological, photochemical or pollution features. A rising trend in annual averaged Eight-hour Average Ozone Concentrations (O 3 -8hr) from 2014 to 2016 was observed for all regions, except for the Tibetan Plateau. The mean values of annual and 90 percentile concentrations for all 338 cities were 82.6±14.6 and 133.9±25.8μg/m 3 , respectively, in 2015. The regionalization results of ozone were found to be influenced greatly by terrain features, indicating significant terrain and landform effects on ozone spatial correlations. Among 12 regions, North China Plain, Huanghuai Plain, Central Yangtze River Plain, Pearl River Delta and Sichuan Basin were realized as priority regions for mitigation strategies, due to their higher ozone concentrations and dense population. Copyright © 2017. Published by Elsevier B.V.

  4. Regulation of ozone-induced lung inflammation and injury by the β-galactoside-binding lectin galectin-3

    Energy Technology Data Exchange (ETDEWEB)

    Sunil, Vasanthi R., E-mail: sunilva@pharmacy.rutgers.edu [Department of Pharmacology and Toxicology, Rutgers University, Ernest Mario School of Pharmacy, Piscataway, NJ (United States); Francis, Mary, E-mail: maryfranrutgers@gmail.com [Department of Pharmacology and Toxicology, Rutgers University, Ernest Mario School of Pharmacy, Piscataway, NJ (United States); Vayas, Kinal N., E-mail: kinalv5@gmail.com [Department of Pharmacology and Toxicology, Rutgers University, Ernest Mario School of Pharmacy, Piscataway, NJ (United States); Cervelli, Jessica A., E-mail: j.cervelli@pharmacy.rutgers.edu [Department of Pharmacology and Toxicology, Rutgers University, Ernest Mario School of Pharmacy, Piscataway, NJ (United States); Choi, Hyejeong, E-mail: choi@eohsi.rutgers.edu [Department of Pharmacology and Toxicology, Rutgers University, Ernest Mario School of Pharmacy, Piscataway, NJ (United States); Laskin, Jeffrey D., E-mail: jlaskin@eohsi.rutgers.edu [Department of Environmental and Occupational Medicine, Rutgers University, Robert Wood Johnson Medical School, Piscataway, NJ (United States); Laskin, Debra L., E-mail: laskin@eohsi.rutgers.edu [Department of Pharmacology and Toxicology, Rutgers University, Ernest Mario School of Pharmacy, Piscataway, NJ (United States)

    2015-04-15

    Macrophages play a dual role in ozone toxicity, contributing to both pro- and anti-inflammatory processes. Galectin-3 (Gal-3) is a lectin known to regulate macrophage activity. Herein, we analyzed the role of Gal-3 in the response of lung macrophages to ozone. Bronchoalveolar lavage (BAL) and lung tissue were collected 24–72 h after exposure (3 h) of WT and Gal-3{sup -/-} mice to air or 0.8 ppm ozone. In WT mice, ozone inhalation resulted in increased numbers of proinflammatory (Gal-3{sup +}, iNOS{sup +}) and anti-inflammatory (MR-1{sup +}) macrophages in the lungs. While accumulation of iNOS{sup +} macrophages was attenuated in Gal-3{sup -/-} mice, increased numbers of enlarged MR-1{sup +} macrophages were noted. This correlated with increased numbers of macrophages in BAL. Flow cytometric analysis showed that these cells were CD11b{sup +} and consisted mainly (> 97%) of mature (F4/80{sup +}CD11c{sup +}) proinflammatory (Ly6GLy6C{sup hi}) and anti-inflammatory (Ly6GLy6C{sup lo}) macrophages. Increases in both macrophage subpopulations were observed following ozone inhalation. Loss of Gal-3 resulted in a decrease in Ly6C{sup hi} macrophages, with no effect on Ly6C{sup lo} macrophages. CD11b{sup +}Ly6G{sup +}Ly6C{sup +} granulocytic (G) and monocytic (M) myeloid derived suppressor cells (MDSC) were also identified in the lung after ozone. In Gal-3{sup -/-} mice, the response of G-MDSC to ozone was attenuated, while the response of M-MDSC was heightened. Changes in inflammatory cell populations in the lung of ozone treated Gal-3{sup -/-} mice were correlated with reduced tissue injury as measured by cytochrome b5 expression. These data demonstrate that Gal-3 plays a role in promoting proinflammatory macrophage accumulation and toxicity in the lung following ozone exposure. - Highlights: • Multiple monocytic-macrophage subpopulations accumulate in the lung after ozone inhalation. • Galectin-3 plays a proinflammatory role in ozone-induced lung injury. • In the

  5. The Antarctic ozone hole

    International Nuclear Information System (INIS)

    Jones, Anna E

    2008-01-01

    Since the mid 1970s, the ozone layer over Antarctica has experienced massive destruction during every spring. In this article, we will consider the atmosphere, and what ozone and the ozone layer actually are. We explore the chemistry responsible for the ozone destruction, and learn about why conditions favour ozone destruction over Antarctica. For the historical perspective, the events leading up to the discovery of the 'hole' are presented, as well as the response from the international community and the measures taken to protect the ozone layer now and into the future

  6. Evidence for a continuous decline in lower stratospheric ozone offsetting ozone layer recovery

    Science.gov (United States)

    Ball, William T.; Alsing, Justin; Mortlock, Daniel J.; Staehelin, Johannes; Haigh, Joanna D.; Peter, Thomas; Tummon, Fiona; Stübi, Rene; Stenke, Andrea; Anderson, John; Bourassa, Adam; Davis, Sean M.; Degenstein, Doug; Frith, Stacey; Froidevaux, Lucien; Roth, Chris; Sofieva, Viktoria; Wang, Ray; Wild, Jeannette; Yu, Pengfei; Ziemke, Jerald R.; Rozanov, Eugene V.

    2018-02-01

    Ozone forms in the Earth's atmosphere from the photodissociation of molecular oxygen, primarily in the tropical stratosphere. It is then transported to the extratropics by the Brewer-Dobson circulation (BDC), forming a protective ozone layer around the globe. Human emissions of halogen-containing ozone-depleting substances (hODSs) led to a decline in stratospheric ozone until they were banned by the Montreal Protocol, and since 1998 ozone in the upper stratosphere is rising again, likely the recovery from halogen-induced losses. Total column measurements of ozone between the Earth's surface and the top of the atmosphere indicate that the ozone layer has stopped declining across the globe, but no clear increase has been observed at latitudes between 60° S and 60° N outside the polar regions (60-90°). Here we report evidence from multiple satellite measurements that ozone in the lower stratosphere between 60° S and 60° N has indeed continued to decline since 1998. We find that, even though upper stratospheric ozone is recovering, the continuing downward trend in the lower stratosphere prevails, resulting in a downward trend in stratospheric column ozone between 60° S and 60° N. We find that total column ozone between 60° S and 60° N appears not to have decreased only because of increases in tropospheric column ozone that compensate for the stratospheric decreases. The reasons for the continued reduction of lower stratospheric ozone are not clear; models do not reproduce these trends, and thus the causes now urgently need to be established.

  7. Evidence for a Continuous Decline in Lower Stratospheric Ozone Offsetting Ozone Layer Recovery

    Science.gov (United States)

    Ball, William T.; Alsing, Justin; Mortlock, Daniel J.; Staehelin, Johannes; Haigh, Joanna D.; Peter, Thomas; Tummon, Fiona; Stuebi, Rene; Stenke, Andrea; Anderson, John; hide

    2018-01-01

    Ozone forms in the Earth's atmosphere from the photodissociation of molecular oxygen, primarily in the tropical stratosphere. It is then transported to the extratropics by the Brewer-Dobson circulation (BDC), forming a protective "ozone layer" around the globe. Human emissions of halogen-containing ozone-depleting substances (hODSs) led to a decline in stratospheric ozone until they were banned by the Montreal Protocol, and since 1998 ozone in the upper stratosphere is rising again, likely the recovery from halogen-induced losses. Total column measurements of ozone between the Earth's surface and the top of the atmosphere indicate that the ozone layer has stopped declining across the globe, but no clear increase has been observed at latitudes between 60degS and 60degN outside the polar regions (60-90deg). Here we report evidence from multiple satellite measurements that ozone in the lower stratosphere between 60degS and 60degN has indeed continued to decline since 1998. We find that, even though upper stratospheric ozone is recovering, the continuing downward trend in the lower stratosphere prevails, resulting in a downward trend in stratospheric column ozone between 60degS and 60degN. We find that total column ozone between 60degS and 60degN appears not to have decreased only because of increases in tropospheric column ozone that compensate for the stratospheric decreases. The reasons for the continued reduction of lower stratospheric ozone are not clear; models do not reproduce these trends, and thus the causes now urgently need to be established.

  8. The benefit of modeled ozone data for the reconstruction of a 99-year UV radiation time series

    Science.gov (United States)

    Junk, J.; Feister, U.; Helbig, A.; GöRgen, K.; Rozanov, E.; KrzyśCin, J. W.; Hoffmann, L.

    2012-08-01

    Solar erythemal UV radiation (UVER) is highly relevant for numerous biological processes that affect plants, animals, and human health. Nevertheless, long-term UVER records are scarce. As significant declines in the column ozone concentration were observed in the past and a recovery of the stratospheric ozone layer is anticipated by the middle of the 21st century, there is a strong interest in the temporal variation of UVERtime series. Therefore, we combined ground-based measurements of different meteorological variables with modeled ozone data sets to reconstruct time series of daily totals of UVER at the Meteorological Observatory, Potsdam, Germany. Artificial neural networks were trained with measured UVER, sunshine duration, the day of year, measured and modeled total column ozone, as well as the minimum solar zenith angle. This allows for the reconstruction of daily totals of UVERfor the period from 1901 to 1999. Additionally, analyses of the long-term variations from 1901 until 1999 of the reconstructed, new UVER data set are presented. The time series of monthly and annual totals of UVERprovide a long-term meteorological basis for epidemiological investigations in human health and occupational medicine for the region of Potsdam and Berlin. A strong benefit of our ANN-approach is the fact that it can be easily adapted to different geographical locations, as successfully tested in the framework of the COSTAction 726.

  9. Ozonated Olive Oils and Troubles

    Directory of Open Access Journals (Sweden)

    Bulent Uysal

    2014-04-01

    Full Text Available One of the commonly used methods for ozone therapy is ozonated oils. Most prominent type of used oils is extra virgin olive oil. But still, each type of unsaturated oils may be used for ozonation. There are a lot of wrong knowledge on the internet about ozonated oils and its use as well. Just like other ozone therapy studies, also the studies about ozone oils are inadequate to avoid incorrect knowledge. Current data about ozone oil and its benefits are produced by supplier who oversees financial interests and make misinformation. Despite the rapidly increasing ozone oil sales through the internet, its quality and efficacy is still controversial. Dozens of companies and web sites may be easily found to buy ozonated oil. But, very few of these products are reliable, and contain sufficiently ozonated oil. This article aimed to introduce the troubles about ozonated oils and so to inform ozonated oil users. [J Intercult Ethnopharmacol 2014; 3(2.000: 49-50

  10. Trauma exposure and heavy drinking and drug use among college students: Identifying the roles of negative and positive affect lability in a daily diary study.

    Science.gov (United States)

    Weiss, Nicole H; Bold, Krysten W; Contractor, Ateka A; Sullivan, Tami P; Armeli, Stephen; Tennen, Howard

    2018-04-01

    Trauma exposure is linked to heavy drinking and drug use among college students. Extant research reveals positive associations between negative affect lability and both trauma exposure and alcohol use. This study aimed to extend past research by using daily diary methods to test whether (a) individuals with (versus without) trauma exposure experience greater negative and positive affect lability, (b) negative and positive affect lability are associated with heavy drinking and drug use, and (c) negative and positive affect lability mediate the relations between trauma exposure and heavy drinking and drug use. Participants were 1640 college students (M age=19.2, 54% female, 80% European American) who provided daily diary data for 30days via online surveys. Daily diaries assessed negative and positive affect and substance use (i.e., percent days of heavy drinking, percent days of drug use, total number of drugs used). Individuals with (versus without) a history of trauma exposure demonstrated higher levels of negative and positive affect lability. Negative, but not positive, affect lability was associated with percent days of heavy drinking, percent days of drug use, and total number of drugs used, and mediated the associations between trauma exposure and heavy drinking and drug use outcomes. Findings provide support for the underlying role of negative affect lability in the relations between trauma exposure and heavy drinking and drug use among college students, suggesting that treatments targeting negative affect lability may potentially serve to reduce heavy drinking and drug use among trauma-exposed college students. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. SMM mesospheric ozone measurements

    Science.gov (United States)

    Aikin, A. C.

    1990-01-01

    The main objective was to understand the secular and seasonal behavior of ozone in the lower mesosphere, 50 to 70 km. This altitude region is important in understanding the factors which determine ozone behavior. A secondary objective is the study of stratospheric ozone in the polar regions. Use is made of results from the SBUV satellite borne instrument. In the Arctic the interaction between chlorine compounds and low molecular weight hydrocarbons is studied. More than 30,000 profiles were obtained using the UVSP instrument on the SMM spacecraft. Several orbits of ozone data per day were obtained allowing study of the current rise in solar activity from the minimum until the present. Analysis of Nimbus 7 SBUV data in Antarctic spring indicates that ozone is depleted within the polar vortex relative to ozone outside the vortex. This depletion confirms the picture of ozone loss at altitudes where polar stratospheric clouds exist. In addition, there is ozone loss above the cloud level indicating that there is another mechanism in addition to ozone loss initiated by heterogeneous chlorine reactions on cloud particles.

  12. Ozonation of 1,2-dihydroxybenzene in the presence of activated carbon.

    Science.gov (United States)

    Zaror, C; Soto, G; Valdés, H; Mansilla, H

    2001-01-01

    This work aims at obtaining experimental data on ozonation of 1,2-dihydroxybenzene (DHB) in the presence of activated carbon, with a view to assessing possible changes in its surface chemical structure and adsorption capacity. Experiments were conducted in a 0.5 L reactor, loaded with 2 g Filtrasorb 400 granular activated carbon, and 1-5 mM DHB aqueous solution at pH 2-8. Ozone gas was generated with an Ozocav generator, and fed into the reactor for a given exposure time, in the range 0.5-240 min, at 25 degrees C and 1 atm. After each run, liquid and activated carbon samples were taken for chemical assays. Soluble organic groups present on the active carbon surface were desorbed and analysed by GC-MS and HPLC. Activated carbon chemical surface properties were analysed using TPD, FT-IR, and XPS techniques. Reactions between ozone and adsorbed DHB were shown to be fast, leading to formation of C-6, C-4 and C-2 by-products. Oxygenated surface groups, particularly, COOH and C = O, increased as a result of ozonation.

  13. Surface ozone pollution in Poland - observations and modelling support for a two-year assessment 2012-2013

    Science.gov (United States)

    Struzewska, Joanna; Kaminski, Jacek W.; Durka, Pawel

    2015-04-01

    The concentrations of near-surface ozone in terms of long term objectives and target values are exceeded at many monitoring sites in Poland. At the request of the Chief Inspectorate of Environmental Protection, an assessment of ozone impact on human health and ecosystems in Poland was undertaken, based on the GEM-AQ model calculations for the period 2012-2013. GEM-AQ (Kaminski et al., 2008) is a comprehensive chemical weather model where air quality processes (chemistry and aerosols) are implemented on-line in the operational weather prediction model developed at Environment Canada (Cote et al., 1998). For this project the model was run in a self-nesting mode with the target grid centered over Poland with the resolution of 5 km. The EMEP emission inventory was refined based on GIS information. Modelling results were evaluated against ozone and NO2 measurements from available monitoring stations in Poland using the DeltaTool developed in the scope of FAIRMODE. We will present exposure levels to high ozone concentrations in terms of number of days with exceeded target values as well as indices AOT40 and SOMO35. Differences between exposure diagnostics in 2012 and 2013 will be discussed.

  14. Ozone Depletion in Tropospheric Volcanic Plumes: From Halogen-Poor to Halogen-Rich Emissions

    Directory of Open Access Journals (Sweden)

    Tjarda J. Roberts

    2018-02-01

    Full Text Available Volcanic halogen emissions to the troposphere undergo a rapid plume chemistry that destroys ozone. Quantifying the impact of volcanic halogens on tropospheric ozone is challenging, only a few observations exist. This study presents measurements of ozone in volcanic plumes from Kīlauea (HI, USA, a low halogen emitter. The results are combined with published data from high halogen emitters (Mt Etna, Italy; Mt Redoubt, AK, USA to identify controls on plume processes. Ozone was measured during periods of relatively sustained Kīlauea plume exposure, using an Aeroqual instrument deployed alongside Multi-Gas SO2 and H2S sensors. Interferences were accounted for in data post-processing. The volcanic H2S/SO2 molar ratio was quantified as 0.03. At Halema‘uma‘u crater-rim, ozone was close to ambient in the emission plume (at 10 ppmv SO2. Measurements in grounding plume (at 5 ppmv SO2 about 10 km downwind of Pu‘u ‘Ō‘ō showed just slight ozone depletion. These Kīlauea observations contrast with substantial ozone depletion reported at Mt Etna and Mt Redoubt. Analysis of the combined data from these three volcanoes identifies the emitted Br/S as a strong but non-linear control on the rate of ozone depletion. Model simulations of the volcanic plume chemistry highlight that the proportion of HBr converted into reactive bromine is a key control on the efficiency of ozone depletion. This underlines the importance of chemistry in the very near-source plume on the fate and atmospheric impacts of volcanic emissions to the troposphere.

  15. VOC reactivity and its effect on ozone production during the HaChi summer campaign

    Directory of Open Access Journals (Sweden)

    L. Ran

    2011-05-01

    Full Text Available Measurements of ozone and its precursors conducted within the HaChi (Haze in China project in summer 2009 were analyzed to characterize volatile organic compounds (VOCs and their effects on ozone photochemical production at a suburban site in the North China Plain (NCP. Ozone episodes, during which running 8-h average ozone concentrations exceeding 80 ppbv lasted for more than 4 h, occurred on about two thirds of the observational days during the 5-week field campaign. This suggests continuous ozone exposure risks in this region in the summer. Average concentrations of nitrogen oxides (NOx and VOCs are about 20 ppbv and 650 ppbC, respectively. On average, total VOC reactivity is dominated by anthropogenic VOCs. The contribution of biogenic VOCs to total ozone-forming potential, however, is also considerable in the daytime. Key species associated with ozone photochemical production are 2-butenes (18 %, isoprene (15 %, trimethylbenzenes (11 %, xylenes (8.5 %, 3-methylhexane (6 %, n-hexane (5 % and toluene (4.5 %. Formation of ozone is found to be NOx-limited as indicated by measured VOCs/NOx ratios and further confirmed by a sensitivity study using a photochemical box model NCAR_MM. The Model simulation suggests that ozone production is also sensitive to changes in VOC reactivity under the NOx-limited regime, although this sensitivity depends strongly on how much NOx is present.

  16. Potential ozone impacts of excess NO2 emissions from diesel particulate filters for on- and off-road diesel engines.

    Science.gov (United States)

    Bar-llan, Amnon; Johnson, Jeremiah R; Denbleyker, Allison; Chan, Lit-Mian; Yarwood, Gregory; Hitchcock, David; Pinto, Joseph P

    2010-08-01

    This study considers potential impacts of increased use of diesel oxidation catalysts (DOCs) and catalyzed diesel particulate filters (DPFs) on ozone formation in the Dallas/ Fort Worth (DFW) area. There is concern that excess nitrogen dioxide (NO2) emissions from vehicles equipped with these devices could increase ambient ozone levels. The approach involved developing two scenarios for use of these devices, quantifying excess NO2 emissions in each scenario, and using a photochemical model to estimate the resulting ozone changes. In the "maximum penetration" scenario, DOC/DPF devices in a 2009 fleet of heavy-duty on-road trucks, school buses, and construction equipment were significantly increased by accelerating turnover of these vehicles and equipment to models that would require DOCs/DPFs. In the "realistic" scenario, current fractional usage of these devices was assessed for 2009. For both scenarios, excess NO2 emissions from DOCs/DPFs were estimated using U.S. Environmental Protection Agency's MOBILE6 and NONROAD emissions inventory modeling tools. The emissions analyses were used to adjust the DFW photochemical modeling emissions inventories and the Comprehensive Air Quality Model with extensions air quality model was rerun for the DFW area to determine the impact of these two scenarios on ozone formation. The maximum penetration scenario, which showed an overall reduction in oxides of nitrogen (NO(x)) because of the accelerated turnover of equipment to cleaner models, resulted in a net decrease in daily maximum 8-hr ozone of 4-5 parts per billion (ppb) despite the increase in NO2 emissions. The realistic scenario resulted in a small increase in daily maximum 8-hr ozone of less than 1 ppb for the DFW area. It was concluded that the excess NO2 emissions from DOC/DPF devices result in very small ozone impacts, particularly for the realistic scenario, in the DFW area. There are noticeable decreases in ozone for the maximum penetration scenario because NO

  17. Understanding Adherence to Daily and Intermittent Regimens of Oral HIV Pre-exposure Prophylaxis Among Men Who Have Sex with Men in Kenya

    OpenAIRE

    Mugo, Peter Mwangi; Sanders, Eduard J.; Mutua, Gaudensia; van der Elst, Elisabeth; Anzala, Omu; Barin, Burc; Bangsberg, David R.; Priddy, Frances H.; Haberer, Jessica E.

    2014-01-01

    A qualitative assessment of Kenyan men who have sex with men taking daily and intermittent oral HIV pre-exposure prophylaxis (PrEP) found stigma, sex work, mobility, and alcohol impacted adherence. We analyzed quantitative data from the same cohort to explore different definitions of intermittent adherence. Volunteers were randomized to daily emtricitabine/tenofovir or placebo, or intermittent (prescription: Mondays/Fridays/after sex, maximum 1 dose/day) emtricitabine/tenofovir or placebo (2:...

  18. Impact of climate change on ozone-related mortality and morbidity in Europe.

    Science.gov (United States)

    Orru, Hans; Andersson, Camilla; Ebi, Kristie L; Langner, Joakim; Aström, Christofer; Forsberg, Bertil

    2013-02-01

    Ozone is a highly oxidative pollutant formed from precursors in the presence of sunlight, associated with respiratory morbidity and mortality. All else being equal, concentrations of ground-level ozone are expected to increase due to climate change. Ozone-related health impacts under a changing climate are projected using emission scenarios, models and epidemiological data. European ozone concentrations are modelled with the model of atmospheric transport and chemistry (MATCH)-RCA3 (50×50 km). Projections from two climate models, ECHAM4 and HadCM3, are applied under greenhouse gas emission scenarios A2 and A1B, respectively. We applied a European-wide exposure-response function to gridded population data and country-specific baseline mortality and morbidity. Comparing the current situation (1990-2009) with the baseline period (1961-1990), the largest increase in ozone-associated mortality and morbidity due to climate change (4-5%) have occurred in Belgium, Ireland, the Netherlands and the UK. Comparing the baseline period and the future periods (2021-2050 and 2041-2060), much larger increases in ozone-related mortality and morbidity are projected for Belgium, France, Spain and Portugal, with the impact being stronger using the climate projection from ECHAM4 (A2). However, in Nordic and Baltic countries the same magnitude of decrease is projected. The current study suggests that projected effects of climate change on ozone concentrations could differentially influence mortality and morbidity across Europe.

  19. Photoprotection in moisturizers and daily-care products.

    Science.gov (United States)

    Seite, S; Fourtanier, A; Rougier, A

    2010-10-01

    During usual daily activities, an appropriate protection against solar UV exposure should prevent clinical, cellular and molecular changes potentially leading to photoaging. In skin areas regularly exposed to sun, UV-damage is superimposed to tissue degeneration resulting from chronological aging. It is, therefore, important to know if moisturizers and daily-care products containing UVA absorbers combined with UVB ones are able to prevent these skin damages. This review will summarize clinical studies evaluating this topic. These studies demonstrate that broad-spectrum protection in moisturizers or daily-care products can prevent the "silent" sub-erythemal cumulative effects of UVR from inadvertent sun exposure.

  20. Effects of Drought Stress and Ozone Exposure on Isoprene Emissions from Oak Seedlings in Texas

    Science.gov (United States)

    Madronich, M. B.; Harte, A.; Schade, G. W.

    2014-12-01

    Isoprene is the dominant hydrocarbon emitted by plants to the atmosphere with an approximate global emission of 550 Tg C yr-1. Isoprene emission studies have elucidated plants' isoprene production capacity, and the controlling factors of instantaneous emissions. However, it is not yet well understood how long-term climatic factors such as drought and increasing ozone concentrations affect isoprene emission rates. Drought reduces photosynthetic activity and is thus expected to reduce isoprene emission rate, since isoprene production relies on photosynthates. On the other hand, ozone is also known to negatively affect photosynthesis rates, but can instead increase isoprene emissions. These apparent inconsistencies and a lack of experimental data make it difficult to accurately parameterize isoprene emission responses to changing environmental conditions. The objective of this work is to reduce some of these uncertainties, using oak seedlings as a study system. Our project focuses on isoprene emission responses of oak trees to typical summer drought and high ozone conditions in Texas. We report on experiments conducted using a laboratory whole-plant chamber and leaf-level data obtained from greenhouse-grown seedlings. The chamber experiment studied the effects of ozone and drought on isoprene emissions from >3 year old oak seedlings under controlled conditions of photosynthetically active radiation (PAR), temperature, soil-moisture and the chamber's air composition. Stress in plants was induced by manipulating potted soil-moisture and ozone concentration in the chamber. The greenhouse study focused on understanding the effects of drought under Texas climatic conditions. For this study we used two year old seedlings of water oak (Quercus nigra) and post oak (Quercus stellata). Temperature, humidity and light in the greenhouse followed local conditions. Leaf-level conductance, photosynthesis measurements and isoprene sampling were carried out under controlled leaf

  1. PHOTOCHEMICAL AIR POLLUTION IN THE NORTH OF PORTUGAL: A HIGH TROPOSHERIC OZONE EPISODE

    Science.gov (United States)

    Monteiro, A.; Carvalho, A.; Tchepel, O.; Ferreira, J.; Martins, H.; Miranda, A.; Borrego, C.; Saavedra, S.; Rodríguez, A.; Souto, J. A.

    2009-12-01

    Very high concentrations of ozone are continuously measured at the monitoring station at Lamas d’Olo, located at the North of Portugal,. A particular high photochemical episode occurred between 11 and 13 of July 2005, registering ozone hourly maximum values above 350 µg.m-3. This ozone-rich episode is investigated in this paper, in order to identify its origin and formation. Besides the analysis of both meteorological and air quality monitoring datasets, a numerical modelling approach, based on MM5-CAMx system, was used to simulate the dispersion and transport (horizontal and vertical) of the photochemical pollutants and its precursors. A cross spectrum analysis of the meteorological and air quality time series was performed, in the frequency domain, to establish the relationships between ozone data measured at Lamas d’Olo with air quality data from neighbourhood stations and meteorological parameters. Results point out different behaviour/contribution between the analysed sites. Moreover, different contributions of the u and v wind component on the ozone concentration fluctuations were found suggesting the presence a mountain breeze circulation and a north synoptic transport. The preliminary modelling results pointed out that the vertical transport of pollutants are responsible for the measured high concentrations, combined with particular meteorological conditions, related to the planetary boundary layer (PBL) development. The pollutants transported and existent at high vertical levels are captured/trapped when the PBL height reaches its daily maximum, and extremely high ozone ground level concentrations are consequently measured.

  2. Inhomogeneous ozone doping and heat induced defects in graphene studied by infrared near-field microscopy

    Science.gov (United States)

    Wang, Wenjie; Zhang, Jiawei; Deng, Haiming; Liu, Megnkun; Xu, Du

    With the potential use of surface plasmon such as transfer data many orders faster than traditional wires, it has been very popular in research. The fact is that the wavelength of of plasmon is much shorter than the one of free space radiation. The UV ozone doping level can be fine controlled in room temperature creating selected plasmon circuit. We study inhomogeneous graphene plasmonics in ozone doped graphene using scattering-type scanning near-field infrared microscopy and spectroscopy. The single layer and bilayer graphene are doped with different dosage of ozone under UV exposure, which lead to surface inhomogeneity and inhomogeneous graphene plasmon polarition excitation under tip. After annealing the ozone doped graphene in air, the inhomogeneous doping induced plasmons disappear, together with the occurrence of local defects after high temperature annealing.

  3. Effects of a modular two-step ozone-water and annealing process on silicon carbide graphene

    Energy Technology Data Exchange (ETDEWEB)

    Webb, Matthew J., E-mail: matthew.webb@cantab.net; Lundstedt, Anna; Grennberg, Helena [Department of Chemistry—BMC, Uppsala University, Box 576, SE-751 23 Uppsala (Sweden); Polley, Craig; Niu, Yuran; Zakharov, Alexei A.; Balasubramanian, Thiagarajan [MAX IV Laboratory, Lund University, 22100 Lund (Sweden); Dirscherl, Kai [DFM—Danish Fundamental Metrology, Matematiktorvet 307, DK-2800 Lyngby (Denmark); Burwell, Gregory; Guy, Owen J. [College of Engineering, Faraday Tower, Singleton Park, Swansea University, Swansea SA2 8PP (United Kingdom); Palmgren, Pål [VG Scienta Scientific AB, Box 15120, Vallongatan 1, SE-750 15 Uppsala (Sweden); Yakimova, Rositsa [Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping (Sweden)

    2014-08-25

    By combining ozone and water, the effect of exposing epitaxial graphene on silicon carbide to an aggressive wet-chemical process has been evaluated after high temperature annealing in ultra high vacuum. The decomposition of ozone in water produces a number of oxidizing species, however, despite long exposure times to the aqueous-ozone environment, no graphene oxide was observed after the two-step process. The systems were comprehensively characterized before and after processing using Raman spectroscopy, core level photoemission spectroscopy, and angle resolved photoemission spectroscopy together with low energy electron diffraction, low energy electron microscopy, and atomic force microscopy. In spite of the chemical potential of the aqueous-ozone reaction environment, the graphene domains were largely unaffected raising the prospect of employing such simple chemical and annealing protocols to clean or prepare epitaxial graphene surfaces.

  4. Ozone Antimicrobial Efficacy

    Science.gov (United States)

    Ozone is a potent germicide that has been used extensively for water purification. In Europe, 90 percent of the municipal water systems are treated with ozone, and in France, ozone has been used to treat drinking water since 1903. However, there is limited information on the bioc...

  5. Tropospheric ozone using an emission tagging technique in the CAM-Chem and WRF-Chem models

    Science.gov (United States)

    Lupascu, A.; Coates, J.; Zhu, S.; Butler, T. M.

    2017-12-01

    Tropospheric ozone is a short-lived climate forcing pollutant. High concentration of ozone can affect human health (cardiorespiratory and increased mortality due to long-term exposure), and also it damages crops. Attributing ozone concentrations to the contributions from different sources would indicate the effects of locally emitted or transported precursors on ozone levels in specific regions. This information could be used as an important component of the design of emissions reduction strategies by indicating which emission sources could be targeted for effective reductions, thus reducing the burden of ozone pollution. Using a "tagging" approach within the CAM-Chem (global) and WRF-Chem (regional) models, we can quantify the contribution of individual emission of NOx and VOC precursors on air quality. Hence, when precursor emissions of NOx are tagged, we have seen that the largest contributors on ozone levels are the anthropogenic sources, while in the case of precursor emissions of VOCs, the biogenic sources and methane account for more than 50% of ozone levels. Further, we have extended the NOx tagging method in order to investigate continental source region contributions to concentrations of ozone over various receptor regions over the globe, with a zoom over Europe. In general, summertime maximum ozone in most receptor regions is largely attributable to local emissions of anthropogenic NOx and biogenic VOC. During the rest of the year, especially during springtime, ozone in most receptor regions shows stronger influences from anthropogenic emissions of NOx and VOC in remote source regions.

  6. Development of a portable instrument to measure ozone production rates in the troposphere

    Science.gov (United States)

    Sklaveniti, Sofia; Locoge, Nadine; Stevens, Philip; Kumar, Vinod; Sinha, Vinayak; Dusanter, Sébastien

    2015-04-01

    Ground-level ozone is a key species related to air pollution, causing respiratory problems, damaging crops and forests, and affecting the climate. Our current understanding of the tropospheric ozone-forming chemistry indicates that net ozone production occurs via reactions of peroxy radicals (HO2 + RO2) with NO producing NO2, whose photolysis leads to O3 formation. Production rates of tropospheric ozone, P(O3), depend on concentrations of oxides of nitrogen (NOx = NO + NO2) and Volatile Organic Compounds (V OCs), but also on production rates of ROx radicals (OH + HO2 + RO2). The formation of ozone follows a complex nonlinear chemistry that makes strategies for reducing ozone difficult to implement. In this context, atmospheric chemistry models are used to develop emission regulations, but there are still uncertainties associated with the chemical mechanisms used in these models. Testing the ozone formation chemistry in atmospheric models is needed, in order to ensure the development of effective strategies for ozone reduction. We will present the development of an instrument for direct measurements of ozone production rates (OPR) in ambient air. The OPR instrument is made of three components: (i) two quartz flow tubes to sample ambient air, one exposed to solar radiation and one covered by a UV filter, (ii) a NO2-to-O3 conversion unit, and (iii) an ozone analyzer. The total amount of ozone exiting each flow tube is conserved in the form of Ox = NO2 + O3. Ozone production rates P(O3) are derived from the difference in Ox concentration between the two flow tubes, divided by the exposure time of air inside the flow tubes. We will present studies that were carried out in the laboratory to characterize each part of the instrument and we will discuss the performances of the OPR instrument based on experiments carried out using synthetic air mixtures of known composition (NOx and V OCs). Chemical modeling will also be presented to assess the reliability of ozone

  7. Effects of El Niño on Summertime Ozone Air Quality in the Eastern United States

    Science.gov (United States)

    Shen, Lu; Mickley, Loretta J.

    2017-12-01

    We investigate the effect of El Niño on maximum daily 8 h average surface ozone over the eastern United States in summer during 1980-2016. El Niño can influence the extratropical climate through the propagation of stationary waves, leading to (1) reduced transport of moist, clean air into the middle and southern Atlantic states and greater subsidence, reduced precipitation, and increased surface solar radiation in this region, as well as (2) intensified southerly flow into the south central states, which here enhances flux of moist and clean air. As a result, each standard deviation increase in the Niño 1 + 2 index is associated with an increase of 1-2 ppbv ozone in the Atlantic states and a decrease of 0.5-2 ppbv ozone in the south central states. These influences can be predicted 4 months in advance. We show that U.S. summertime ozone responds differently to eastern-type El Niño events compared to central-type events.

  8. Extreme events in total ozone over Arosa – Part 1: Application of extreme value theory

    Directory of Open Access Journals (Sweden)

    H. E. Rieder

    2010-10-01

    Full Text Available In this study ideas from extreme value theory are for the first time applied in the field of stratospheric ozone research, because statistical analysis showed that previously used concepts assuming a Gaussian distribution (e.g. fixed deviations from mean values of total ozone data do not adequately address the structure of the extremes. We show that statistical extreme value methods are appropriate to identify ozone extremes and to describe the tails of the Arosa (Switzerland total ozone time series. In order to accommodate the seasonal cycle in total ozone, a daily moving threshold was determined and used, with tools from extreme value theory, to analyse the frequency of days with extreme low (termed ELOs and high (termed EHOs total ozone at Arosa. The analysis shows that the Generalized Pareto Distribution (GPD provides an appropriate model for the frequency distribution of total ozone above or below a mathematically well-defined threshold, thus providing a statistical description of ELOs and EHOs. The results show an increase in ELOs and a decrease in EHOs during the last decades. The fitted model represents the tails of the total ozone data set with high accuracy over the entire range (including absolute monthly minima and maxima, and enables a precise computation of the frequency distribution of ozone mini-holes (using constant thresholds. Analyzing the tails instead of a small fraction of days below constant thresholds provides deeper insight into the time series properties. Fingerprints of dynamical (e.g. ENSO, NAO and chemical features (e.g. strong polar vortex ozone loss, and major volcanic eruptions, can be identified in the observed frequency of extreme events throughout the time series. Overall the new approach to analysis of extremes provides more information on time series properties and variability than previous approaches that use only monthly averages and/or mini-holes and mini-highs.

  9. TOMS EP UV Aerosol Index Daily and Monthly Zonal Means V008 (TOMSEPL3zaer) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — This data product contains TOMS/EP UV Aerosol Index Daily and Monthly Zonal Means Version 8 data in ASCII format.The Total Ozone Mapping Spectrometer (TOMS) Version...

  10. Multi-model assessment of stratospheric ozone return dates and ozone recovery in CCMVal-2 models

    Directory of Open Access Journals (Sweden)

    V. Eyring

    2010-10-01

    Full Text Available Projections of stratospheric ozone from a suite of chemistry-climate models (CCMs have been analyzed. In addition to a reference simulation where anthropogenic halogenated ozone depleting substances (ODSs and greenhouse gases (GHGs vary with time, sensitivity simulations with either ODS or GHG concentrations fixed at 1960 levels were performed to disaggregate the drivers of projected ozone changes. These simulations were also used to assess the two distinct milestones of ozone returning to historical values (ozone return dates and ozone no longer being influenced by ODSs (full ozone recovery. The date of ozone returning to historical values does not indicate complete recovery from ODSs in most cases, because GHG-induced changes accelerate or decelerate ozone changes in many regions. In the upper stratosphere where CO2-induced stratospheric cooling increases ozone, full ozone recovery is projected to not likely have occurred by 2100 even though ozone returns to its 1980 or even 1960 levels well before (~2025 and 2040, respectively. In contrast, in the tropical lower stratosphere ozone decreases continuously from 1960 to 2100 due to projected increases in tropical upwelling, while by around 2040 it is already very likely that full recovery from the effects of ODSs has occurred, although ODS concentrations are still elevated by this date. In the midlatitude lower stratosphere the evolution differs from that in the tropics, and rather than a steady decrease in ozone, first a decrease in ozone is simulated from 1960 to 2000, which is then followed by a steady increase through the 21st century. Ozone in the midlatitude lower stratosphere returns to 1980 levels by ~2045 in the Northern Hemisphere (NH and by ~2055 in the Southern Hemisphere (SH, and full ozone recovery is likely reached by 2100 in both hemispheres. Overall, in all regions except the tropical lower stratosphere, full ozone recovery from ODSs occurs significantly later than the

  11. Coconut, Fish, and Olive Oil-Rich Diets Modify Ozone-Induced Metabolic Effects

    Science.gov (United States)

    Pulmonary health effects of ozone (O3) exposure are well known; however, the cardiovascular and metabolic consequences are still under investigation. Fish oil (FO) and olive oil (OO) dietary supplementation have several cardioprotective benefits, but it is not established if thes...

  12. Merged SAGE II, Ozone_cci and OMPS ozone profile dataset and evaluation of ozone trends in the stratosphere

    Directory of Open Access Journals (Sweden)

    V. F. Sofieva

    2017-10-01

    Full Text Available In this paper, we present a merged dataset of ozone profiles from several satellite instruments: SAGE II on ERBS, GOMOS, SCIAMACHY and MIPAS on Envisat, OSIRIS on Odin, ACE-FTS on SCISAT, and OMPS on Suomi-NPP. The merged dataset is created in the framework of the European Space Agency Climate Change Initiative (Ozone_cci with the aim of analyzing stratospheric ozone trends. For the merged dataset, we used the latest versions of the original ozone datasets. The datasets from the individual instruments have been extensively validated and intercompared; only those datasets which are in good agreement, and do not exhibit significant drifts with respect to collocated ground-based observations and with respect to each other, are used for merging. The long-term SAGE–CCI–OMPS dataset is created by computation and merging of deseasonalized anomalies from individual instruments. The merged SAGE–CCI–OMPS dataset consists of deseasonalized anomalies of ozone in 10° latitude bands from 90° S to 90° N and from 10 to 50 km in steps of 1 km covering the period from October 1984 to July 2016. This newly created dataset is used for evaluating ozone trends in the stratosphere through multiple linear regression. Negative ozone trends in the upper stratosphere are observed before 1997 and positive trends are found after 1997. The upper stratospheric trends are statistically significant at midlatitudes and indicate ozone recovery, as expected from the decrease of stratospheric halogens that started in the middle of the 1990s and stratospheric cooling.

  13. Tropospheric Ozone from the TOMS TDOT (TOMS-Direct-Ozone-in-Troposphere) Technique During SAFARI-2000

    Science.gov (United States)

    Stone, J. B.; Thompson, A. M.; Frolov, A. D.; Hudson, R. D.; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    There are a number of published residual-type methods for deriving tropospheric ozone from TOMS (Total Ozone Mapping Spectrometer). The basic concept of these methods is that within a zone of constant stratospheric ozone, the tropospheric ozone column can be computed by subtracting stratospheric ozone from the TOMS Level 2 total ozone column, We used the modified-residual method for retrieving tropospheric ozone during SAFARI-2000 and found disagreements with in-situ ozone data over Africa in September 2000. Using the newly developed TDOT (TOMS-Direct-Ozone-in-Troposphere) method that uses TOMS radiances and a modified lookup table based on actual profiles during high ozone pollution periods, new maps were prepared and found to compare better to soundings over Lusaka, Zambia (15.5 S, 28 E), Nairobi and several African cities where MOZAIC aircraft operated in September 2000. The TDOT technique and comparisons are described in detail.

  14. A Review of Atmospheric Ozone and Current Thinking on the Antarctic Ozone Hole.

    Science.gov (United States)

    1987-01-01

    UNIVERSITY OF CALIFORNIA 0 A Review of Atmospheric ozone and Current Thinking on the Antartic Ozone Hole A thesis submitted in partial satisfaction of the...4. TI TLE (Pit 5,1tlfie) S. TYPE OF REPORT & PFRIOO COVERED A Review of Atmospheric Ozone and Current THESIS/DA/;J.At1AAU00 Thinking on the Antartic ...THESIS A Review of Atmospheric Ozone and Current Thinking on the Antartic Ozone Hole by Randolph Antoine Fix Master of Science in Atmospheric Science

  15. From never to daily smoking in 30 months: the predictive value of tobacco and non-tobacco advertising exposure

    Science.gov (United States)

    Morgenstern, Matthis; Sargent, James D; Isensee, Barbara; Hanewinkel, Reiner

    2013-01-01

    Objective To test the specificity of the association between tobacco advertising and youth smoking initiation. Design Longitudinal survey with a 30 month interval. Setting 21 public schools in three German states. Participants A total of 1320 sixth-to-eighth grade students who were never-smokers at baseline (age range at baseline, 10–15 years; mean, 12.3 years). Exposures Exposure to tobacco and non-tobacco advertisements was measured at baseline with images of six tobacco and eight non-tobacco advertisements; students indicated the number of times they had seen each ad and the sum score over all advertisements was used to represent inter-individual differences in the amount of advertising exposure. Primary and secondary outcome measures Established smoking, defined as smoked >100 cigarettes during the observational period, and daily smoking at follow-up. Secondary outcome measures were any smoking and smoking in the last 30 days. Results During the observation period, 5% of the never-smokers at baseline smoked more than 100 cigarettes and 4.4% were classified as daily smokers. After controlling for age, gender, socioeconomic status, school performance, television screen time, personality characteristics and smoking status of peers and parents, each additional 10 tobacco advertising contacts increased the adjusted relative risk for established smoking by 38% (95% CI 16% to 63%; padvertising contact. Conclusions The study confirms a content-specific association between tobacco advertising and smoking behaviour and underlines that tobacco advertising exposure is not simply a marker for adolescents who are generally more receptive or attentive towards marketing. PMID:23794549

  16. Ozone depletion calculations

    International Nuclear Information System (INIS)

    Luther, F.M.; Chang, J.S.; Wuebbles, D.J.; Penner, J.E.

    1992-01-01

    Models of stratospheric chemistry have been primarily directed toward an understanding of the behavior of stratospheric ozone. Initially this interest reflected the diagnostic role of ozone in the understanding of atmospheric transport processes. More recently, interest in stratospheric ozone has arisen from concern that human activities might affect the amount of stratospheric ozone, thereby affecting the ultraviolet radiation reaching the earth's surface and perhaps also affecting the climate with various potentially severe consequences for human welfare. This concern has inspired a substantial effort to develop both diagnostic and prognostic models of stratospheric ozone. During the past decade, several chemical agents have been determined to have potentially significant impacts on stratospheric ozone if they are released to the atmosphere in large quantities. These include oxides of nitrogen, oxides of hydrogen, chlorofluorocarbons, bromine compounds, fluorine compounds and carbon dioxide. In order to assess the potential impact of the perturbations caused by these chemicals, mathematical models have been developed to handle the complex coupling between chemical, radiative, and dynamical processes. Basic concepts in stratospheric modeling are reviewed

  17. Near-ambient ozone concentrations reduce the vigor of Betula and Populus species in Finland.

    Science.gov (United States)

    Oksanen, Elina; Manninen, Sirkku; Vapaavuori, Elina; Holopainen, Toini

    2009-12-01

    In this review the main growth responses of Finnish birch (Betula pendula, B. pubescens) and aspen species (Populus tremula and P. tremuloides x P. tremula) are correlated with ozone exposure, indicated as the AOT40 value. Data are derived from 23 different laboratory, open-top chamber, and free-air fumigation experiments. Our results indicate that these tree species are sensitive to increasing ozone concentrations, though high intraspecific variation exists. The roots are the most vulnerable targets in both genera. These growth reductions, determined from trees grown under optimal nutrient and water supply, were generally accompanied by increased visible foliar injuries, carbon allocation toward defensive compounds, reduced carbohydrate contents of leaves, impaired photosynthesis processes, disturbances in stomatal function, and earlier autumn senescence. Because both genera have shown complex ozone defense and response mechanisms, which are modified by variable environmental conditions, a mechanistically based approach is necessary for accurate ozone risk assessment.

  18. Tibouchina pulchra (Cham.) Cogn., a native Atlantic Forest species, as a bio-indicator of ozone: Visible injury

    Energy Technology Data Exchange (ETDEWEB)

    Furlan, Claudia M. [Departamento de Botanica, Instituto de Biociencias, Universidade de Sao Paulo, CP 11461, 05422-970 Sao Paulo, SP (Brazil)], E-mail: furlancm@yahoo.com.br; Moraes, Regina M.; Bulbovas, Patricia [Secao de Ecologia, Instituto de Botanica, SMA, CP 4005, 01061-970 Sao Paulo (Brazil); Sanz, Maria J. [Fundacion Centro de Estudios Ambientales del Mediterraneo, Parque Tecnologico, E-46980 Paterna, Valencia (Spain); Domingos, Marisa [Secao de Ecologia, Instituto de Botanica, SMA, CP 4005, 01061-970 Sao Paulo (Brazil); Salatino, Antonio [Departamento de Botanica, Instituto de Biociencias, Universidade de Sao Paulo, CP 11461, 05422-970 Sao Paulo, SP (Brazil)

    2008-03-15

    Tibouchina pulchra saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF) and ambient non-filtered air + 40 ppb ozone (NF + O{sub 3}) 8 h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12,895 ppb h{sup -1}, respectively, for the three treatments. After 25 days of exposure (AOT40 = 3871 ppb h{sup -1}), interveinal red stippling appeared in plants in the NF + O{sub 3} chamber. In the NF chamber, symptoms were observed only after 60 days of exposure (AOT40 = 910 ppb h{sup -1}). After 60 days, injured leaves per plant corresponded to 19% in NF + O{sub 3} and 1% in the NF treatment; and the average leaf area injured was 7% within the NF + O{sub 3} and 0.2% within the NF treatment. The extent of leaf area injured (leaf injury index) was mostly explained by the accumulated exposure of ozone (r{sup 2} = 0.89; p < 0.05). - Tibouchina pulchra, a tropical species widely used in Brazilian landscapes as an ornamental tree, is a potential sensitive bio-indicator of ozone air pollution.

  19. Tibouchina pulchra (Cham.) Cogn., a native Atlantic Forest species, as a bio-indicator of ozone: Visible injury

    International Nuclear Information System (INIS)

    Furlan, Claudia M.; Moraes, Regina M.; Bulbovas, Patricia; Sanz, Maria J.; Domingos, Marisa; Salatino, Antonio

    2008-01-01

    Tibouchina pulchra saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF) and ambient non-filtered air + 40 ppb ozone (NF + O 3 ) 8 h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12,895 ppb h -1 , respectively, for the three treatments. After 25 days of exposure (AOT40 = 3871 ppb h -1 ), interveinal red stippling appeared in plants in the NF + O 3 chamber. In the NF chamber, symptoms were observed only after 60 days of exposure (AOT40 = 910 ppb h -1 ). After 60 days, injured leaves per plant corresponded to 19% in NF + O 3 and 1% in the NF treatment; and the average leaf area injured was 7% within the NF + O 3 and 0.2% within the NF treatment. The extent of leaf area injured (leaf injury index) was mostly explained by the accumulated exposure of ozone (r 2 = 0.89; p < 0.05). - Tibouchina pulchra, a tropical species widely used in Brazilian landscapes as an ornamental tree, is a potential sensitive bio-indicator of ozone air pollution

  20. Ozone deposition velocities, reaction probabilities and product yields for green building materials

    Science.gov (United States)

    Lamble, S. P.; Corsi, R. L.; Morrison, G. C.

    2011-12-01

    Indoor surfaces can passively remove ozone that enters buildings, reducing occupant exposure without an energy penalty. However, reactions between ozone and building surfaces can generate and release aerosols and irritating and carcinogenic gases. To identify desirable indoor surfaces the deposition velocity, reaction probability and carbonyl product yields of building materials considered green (listed, recycled, sustainable, etc.) were quantified. Nineteen separate floor, wall or ceiling materials were tested in a 10 L, flow-through laboratory reaction chamber. Inlet ozone concentrations were maintained between 150 and 200 ppb (generally much lower in chamber air), relative humidity at 50%, temperature at 25 °C and exposure occurred over 24 h. Deposition velocities ranged from 0.25 m h -1 for a linoleum style flooring up to 8.2 m h -1 for a clay based paint; reaction probabilities ranged from 8.8 × 10 -7 to 6.9 × 10 -5 respectively. For all materials, product yields of C 1 thru C 12 saturated n-aldehydes, plus acetone ranged from undetectable to greater than 0.70 The most promising material was a clay wall plaster which exhibited a high deposition velocity (5.0 m h -1) and a low product yield (