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Sample records for acute ozone exposure

  1. Acute ozone exposure increases plasma prostaglandin F2 alpha in ozone-sensitive human subjects

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    Schelegle, E.S.; Adams, W.C.; Giri, S.N.; Siefkin, A.D.

    1989-07-01

    Twenty O/sub 3/-sensitive and /sup 2/O O/sub 3/-nonsensitive subjects participated in a study to investigate the effects of disparate O/sub 3/ sensitivity on plasma prostaglandin F2 alpha responses consequent to exposure to ambient O3 concentrations. Subjects were selected from a pool of 75 normal healthy college-aged males who had been previously exposed to 0.35 ppm O3 for 1 h at an exercising VE of 60 L/min. The selection criterion used was the observed decrement in FEV1 after the O/sub 3/ exposure: O/sub 3/-sensitive, FEV1 decrement greater than 24%; O/sub 3/-nonsensitive, FEV1 decrement less than 11%. Each subject was exposed to filtered air and to 0.20 and 0.35 ppm O/sub 3/ for 80 min while exercising at a VE of 50 L/min. These experimental protocols were divided into two 40-min sessions separated by a period of 4 to 10 min. PGF2 alpha, FVC, FEV1, and FEF25-75 were evaluated before, during, and after each protocol. SGaw and Vtg were measured before and after each protocol. Plasma PGF2 alpha was significantly increased in the O/sub 3/-sensitive group during and after the 0.35-ppm O/sub 3/ exposure.

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

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    Schlesinger, R.B.; Driscoll, K.E.; Gunnison, A.F.; Zelikoff, J.T. (New York Univ. Medical Center, NY (USA))

    1990-12-01

    Ozone (O{sub 3}) and nitrogen dioxide (NO{sub 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{sub 3} at 0.1, 0.3, or 1 ppm; NO{sub 2} at 1, 3, or 10 ppm; or to a mixture of 0.3 ppm O{sub 3} and 3 ppm NO{sub 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{sub 3}. Exposure to 10 ppm NO{sub 2} resulted in a depression of 6-keto-PGF1 alpha, while thromboxane B2 (TxB2) was elevated after exposure to 1 ppm NO{sub 2} and depressed following 3 and 10 ppm. The O{sub 3}/NO{sub 2} mixture resulted in synergistic increases in PGE2 and PGF2 alpha, with the response appearing to be driven by O{sub 3}. This study has demonstrated that acute exposure to either O{sub 3} or NO{sub 2} can alter pulmonary arachidonic acid metabolism and that the responses to these oxidants differ, both quantitatively and qualitatively.

  3. Assessment of toxicologic interactions resulting from acute inhalation exposure to sulfuric acid and ozone mixtures

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    Schlesinger, R.B.; Zelikoff, J.T.; Chen, L.C.; Kinney, P.L. (Department of Environmental Medicine, New York University Medical Center, NY (United States))

    1992-08-01

    Studies examining effects of air pollutants often use single compounds, while real world' exposures are to more than one chemical. Thus, it is necessary to assess responses following inhalation of chemical mixtures. Rabbits were exposed for 3 hr to sulfuric acid aerosol at 0, 50, 75, or 125 micrograms/m3 in conjunction with ozone at 0, 0.1, 0.3, or 0.6 ppm, following which broncho-pulmonary lavage was performed. Various pulmonary response endpoints related to general cytotoxicity and macrophage function were examined. In addition, a goal of the study was to define an improved approach to the analysis of data sets involving binary pollutant mixtures. Results were evaluated using analysis of variance with multiple linear contrasts to determine the significance of any effect in the pollutant-exposed groups compared to sham control animals and to assess the type, and extent, of any toxicological interaction between acid and ozone. Interaction was considered to occur when the effects of combined exposure were either significantly greater or less than additive. Pollutant exposures had no effect on lavage fluid levels of lactate dehydrogenase, prostaglandins E2 and F2 alpha, nor on the numbers, viability, or types of immune cells recovered by lavage. Phagocytic activity of macrophages was depressed at the two highest acid levels and at all levels of ozone. Superoxide production by stimulated macrophages was depressed by acid exposure at the two highest concentrations, while ozone alone had no effect. Significant antagonistic interaction was observed following exposure to mixtures of 75 or 125 micrograms/m3 acid with 0.1 or 0.3 ppm ozone. The activity of tumor necrosis factor elicited from stimulated macrophages was depressed by acid at 75 and 125 micrograms/m3 while ozone had no effect. Exposure to mixtures of 125 micrograms/m3 acid with 0.3 or 0.6 ppm ozone resulted in synergistic interaction.

  4. Age-dependence of responses to acute ozone exposure in rats

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    Gunnison, A.F.; Weideman, P.A.; Sobo, M.; Koenig, K.L.; Chen, L.C. (Institute of Environmental Medicine, New York University Medical Center, New York (United States))

    1992-04-01

    In the study reported here, we have extended our initial investigation to include the influence of animal age on temporal aspects of pulmonary AA metabolism and several other responses to brief exposures to 1 ppm ozone. Rats of discrete ages ranging from 13 days to 16 weeks were exposed to 1 ppm ozone or to air for 2, 4, or 6 hr. Immediately following exposure the lungs were lavaged with six consecutive volumes of phosphate-buffered saline and the acellular fluid from the first lavage volume recovered was analyzed for its content of prostaglandin E2 (PGE2), protein, and lactate dehydrogenase. Leukocytes recovered by lavage were quantitated and characterized by viability and percentage of polymorphonuclear (PMN) cells. Several lines of evidence verified that PGE2 was produced by the lung as a consequence of ozone exposure and that its concentration in the fluid from the first lavage was a reasonably good index of pulmonary AA metabolism to prostanoids. We also demonstrated that the lavage process itself stimulates the lung, resulting in increased AA metabolism to prostanoids that were recovered in the second and following lavage volumes. The time course of PGE2 production by the ozone-exposed lung varied considerably with animal age. Neonatal rats 13 days of age were the most sensitive to ozone stimulation. At 2 hr of exposure, PGE2 concentration in the first lung lavage of these animals peaked at values approximately two orders of magnitude above controls and then decreased sharply with continued exposure. Adults and older neonates (18 days of age) were much less responsive to 2-hr exposures; however, continued exposure of these rats for up to 6 hr resulted in increasing PGE2 concentration in the first lung lavage. Other responses showed various degree of age dependence.

  5. Chronic and Acute Ozone Exposure in the Week Prior to Delivery Is Associated with the Risk of Stillbirth

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    Pauline Mendola

    2017-07-01

    Full Text Available Chronic and acute air pollution has been studied in relation to stillbirth with inconsistent findings. We examined stillbirth risk in a retrospective cohort of 223,375 singleton deliveries from 12 clinical sites across the United States. Average criteria air pollutant exposure was calculated using modified Community Multiscale Air Quality models for the day of delivery and each of the seven days prior, whole pregnancy, and first trimester. Poisson regression models using generalized estimating equations estimated the relative risk (RR of stillbirth and 95% confidence intervals (CI in relation to an interquartile range increase in pollutant with adjustment for temperature, clinical, and demographic factors. Ozone (O3 was associated with a 13–22% increased risk of stillbirth on days 2, 3, and 5–7 prior to delivery in single pollutant models, and these findings persisted in multi-pollutant models for days 5 (RR = 1.22, CI = 1.07–1.38 and 6 (RR = 1.18, CI = 1.04–1.33. Whole pregnancy and first trimester O3 increased risk 18–39% in single pollutant models. Maternal asthma increased stillbirth risk associated with chronic PM2.5 and carbon monoxide exposures. Both chronic and acute O3 exposure consistently increased stillbirth risk, while the role of other pollutants varied. Approximately 8000 stillbirths per year in the US may be attributable to O3 exposure.

  6. 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

  7. Acute effect of ozone exposure on daily mortality in seven cities of Jiangsu Province, China: No clear evidence for threshold.

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    Chen, Kai; Zhou, Lian; Chen, Xiaodong; Bi, Jun; Kinney, Patrick L

    2017-05-01

    Few multicity studies have addressed the health effects of ozone in China due to the scarcity of ozone monitoring data. A critical scientific and policy-relevant question is whether a threshold exists in the ozone-mortality relationship. Using a generalized additive model and a univariate random-effects meta-analysis, this research evaluated the relationship between short-term ozone exposure and daily total mortality in seven cities of Jiangsu Province, China during 2013-2014. Spline, subset, and threshold models were applied to further evaluate whether a safe threshold level exists. This study found strong evidence that short-term ozone exposure is significantly associated with premature total mortality. A 10μg/m(3) increase in the average of the current and previous days' maximum 8-h average ozone concentration was associated with a 0.55% (95% posterior interval: 0.34%, 0.76%) increase of total mortality. This finding is robust when considering the confounding effect of PM2.5, PM10, NO2, and SO2. No consistent evidence was found for a threshold in the ozone-mortality concentration-response relationship down to concentrations well below the current Chinese Ambient Air Quality Standard (CAAQS) level 2 standard (160μg/m(3)). Our findings suggest that ozone concentrations below the current CAAQS level 2 standard could still induce increased mortality risks in Jiangsu Province, China. Continuous air pollution control measures could yield important health benefits in Jiangsu Province, China, even in cities that meet the current CAAQS level 2 standard. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Modeled population exposures to ozone

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    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...

  9. Clinical and pathological manifestations of cardiovascular disease in rat models: the influence of acute ozone exposure

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    This paper shows that rat models of cardiovascular diseases have differential degrees of underlying pathologies at a young age. Rodent models of cardiovascular diseases (CVD) and metabolic disorders are used for examining susceptibility variations to environmental exposures. How...

  10. Age-related differences in pulmonary effects of acute and subchronic episodic ozone exposures in Brown Norway rats

    Science.gov (United States)

    Ozone (O3) is known to induce adverse pulmonary and systemic health effects. Importantly, children and older persons are considered at-risk populations for O3-induced dysfunction, yet the mechanisms accounting for the age-related pulmonary responses to O3 are uncertain. In this s...

  11. Statistical estimation of ozone exposure metrics

    Science.gov (United States)

    Blankenship, Erin E.; Stefanski, L. A.

    Data from recent experiments at North Carolina State University and other locations provide a unique opportunity to study the effect of ambient ozone on the growth of clover. The data consist of hourly ozone measurements over a 140 day growing season at eight sites in the US, coupled with clover growth response data measured every 28 days. The objective is to model an indicator of clover growth as a function of ozone exposure. A common strategy for dealing with the numerous hourly ozone measurements is to reduce these to a single summary measurement, a so-called exposure metric, for the growth period of interest. However, the mean ozone value is not necessarily the best summarization, as it is widely believed that low levels of ozone have a negligible effect on growth, whereas peak ozone values are deleterious to plant growth. There are also suspected interactions with available sunlight, temperature and humidity. A number of exposure metrics have been proposed that reflect these beliefs by assigning different weights to ozone values according to magnitude, time of day, temperature and humidity. These weighting schemes generally depend on parameters that have, to date, been subjectively determined. We propose a statistical approach based on profile likelihoods to estimate the parameters in these exposure metrics.

  12. Impact of Ozone Exposure on OPV Efficiency

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    Palankar, Aneeket Jaisukhlal

    Organic solar cells are a considerable promise for alternate energy sources owing to their plentiful, easily accessible and renewable source of power. Degradation on organic film and anode layer are the major factors that determine device reliability and ozone can induce damage to these materials due to its strong oxidizing property. This study measured the sustainability of a type of organic photovoltaic (OPV) film (P3HT:PC71BM) and its anodes (Al and MoO3) to different levels of ozone environment and investigated the impact of ozone exposure on OPV film and anodes efficiency. The devices were fabricated in a Glove Box under controlled N2 atmosphere using Spin Coating and Physical Vapor Deposition and exposed to varied ozone concentrations, followed by J-V measurements to determine the Power Conversion Efficiency and Fill Factor. The effects of ozone exposure on the films were compared vs. the effects of exposure on complete devices with anodes (Al and MoO 3). The results show that the devices decay from normal efficiency (4%) to 0% in 12 hours under 300 ppb (+/-10%) ozone concentration and decay to 0% in 6 hours when the ozone concentration was 600 ppb (+/-10%), when only the polymer thin films are exposed. This established an inverse linear relationship between the decay rate and ozone exposure at high concentrations on the OPV films. Furthermore, the effect of exposure to ambient ozone concentration on the polymer films, which is 70 ppb (+/-15%), was also investigated and the devices were found to decay to 0% in 28 hours, which is much faster than expected. The decay resistance of complete devices when the polymer films are coated with thermally evaporated anodes (Al and MoO3) before exposure to 400 ppb ozone concentration was investigated. The average efficiency of the complete device after 2, 6, 10, 15, 28 and 42 hours exposure in 400 ppb ozone environment was 4.16% with a standard deviation of 0.12%. The test findings for the complete device with coated

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

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    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...

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

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    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...

  15. The role of ozone exposure in the epidemiology of asthma

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    Balmes, J.R. [Univ. of California, San Francisco, CA (United States)

    1993-12-01

    Asthma is a clinical condition characterized by intermittent respiratory symptoms, nonspecific airway hyperresponsiveness, and reversible airway obstruction. Although the pathogenesis of asthma is incompletely understood, it is clear that airway inflammation is a paramount feature of the condition. Because inhalation of ozone by normal, healthy subjects causes increased airway responsiveness and inflammation, it is somewhat surprising that most controlled human exposure studies that have involved asthmatic subjects have not shown them to be especially sensitive to ozone. The acute decrement in lung function that is the end point traditionally used to define sensitivity to ozone in these studies may be due more to neuromuscular mechanisms limiting deep inspiration than to bronchoconstriction. The frequency of asthma attacks following ozone exposures may be a more relevant end point. Epidemiologic studies, rather than controlled human exposure studies, are required to determine whether ozone pollution increases the risk of asthma exacerbations. Asthma affects approximately 10 million people in the United States and, thus, the answer to this question is of considerable public health importance. Both the prevalence and severity of asthma appear to be increasing in many countries. Although increased asthma morbidity and mortality are probably of multifactorial etiology, a contributory role of urban air pollution is plausible. The epidemiologic database to support an association between asthma and ozone exposure is limited, but the results of several studies suggest such an association. Some potential approaches to further investigation of the relationship between asthma and ozone, including those that would link controlled human exposures to population-based studies, are considered. 57 refs.

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

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    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...

  17. Acute Ozone (O3) Exposure Enhances Aortic Contraction in Healthy Rats while Exacerbating Pulmonary Injury in Diabetics

    Science.gov (United States)

    Air pollution exposure affects health adversely in individuals with type 2 diabetes (T2D) and diet induced obesity (DIO). We hypothesized that T2D and DIO would exacerbate O3 induced pulmonary responses and alter arterial reactivity. Male Wistar and Goto Kakizaki (GK) rats, a l...

  18. 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...

  19. Acute inhalation of ozone stimulates bronchial C-fibers and rapidly adapting receptors in dogs

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    Coleridge, J.C.G.; Coleridge, H.M.; Schelegle, E.S.; Green, J.F. (Univ. of California, Davis (United States) Univ. of California, San Francisco (United States))

    1993-05-01

    To identify the afferents responsible for initiating the vagally mediated respiratory changes evoked by acute exposure to ozone, the authors recorded vagal impulses in anesthetized, open-chest, artificially ventilated dogs and examined the pulmonary afferent response to ozone (2--3 ppM in air) delivered to the lower trachea for 20--60 min. Bronchial C-fibers (BrCs) were the lung afferents most susceptible to ozone, the activity of 10 of 11 BrCs increasing from 0.2 [+-] 0.2 to 4.6 [+-] 1.3 impulses/s within 1--7 min of ozone exposure. Ten of 15 rapidly adapting receptors (RARs) were stimulated by ozone, their activity increasing from 1.5 [+-] 0.4 to 4.7 [+-] 0.7 impulses/s. Stimulation of RARs (but not of BrCs) appeared secondary to the ozone-induced reduction of lung compliance because it was abolished by hyperinflation of the lungs. Ozone had little effect on pulmonary C-fibers or slowly adapting pulmonary stretch receptors. The authors' results suggest that both BrCs and RARs contribute to the tachypnea and bronchoconstriction evoked by acute exposure to ozone when vagal conduction is intact and that BrCs alone are responsible for the vagally mediated tachypnea that survives vagal cooling to 7[degrees]C. 23 refs., 5 figs.

  20. Effect of regular aerobic exercise with ozone exposure on peripheral leukocyte populations in Wistar male rats

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    Afshar Jafari

    2009-09-01

    Full Text Available

    • BACKGROUND: The immune system in endurance athletes may be at risk for deleterious effects of gasous pollutants such as ambient ozone. Therefore, this study was performed to assess the effect of regular aerobic exercise with ozone exposure on peripheral leukocytes populations in male Wistar rats.
    • METHODS: Twenty eight 8 weeks old rats were selected and randomly divided into four groups of ozone-unexposed anduntrained (control or group 1, n = 6, ozone-exposed and untrained (group 2, n = 6, ozone-unexposed and trained (group 3, n = 8, ozone-exposed and trained (group 4, n = 8. All animals in groups 3 and 4 were regularly running (20 m/min, 30 min/day on a treadmill for 7 weeks (5 day/week. After the last ozone exposure [0.3 ppm, 30 min per sessions], blood samples were obtained from the cardiac puncture and hematological parameters as well as blood lactate were measured using automatic analyzers. Data were expressed as means (± SD and analyzed by ANOVA and Pearson's correlation tests at p < 0.05.
    • RESULTS: All the hematological parameters differences (except RBC and hemoglobin rate were significantly higher in the trained groups (p < 0.001. However, ozone-induced leukocytosis in the trained (but not in the sedentary rats was statistically higher than in the counterpart groups.
    • CONCLUSIONS: Repeated acute ozone exposure has more additive effect on peripheral leukocyte counts in active animals. But, more researches are needed to identify effects of ozone exposure on other components of the immune system in athletes and non-athletes.
    • KEYWORDS: Moderate Aerobic Exercise, Ozone Exposure,  eukocytosis, Wistar Rats.

  1. 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

    , if any, threshold for ozone's impact on mortality. Additionally, the present study estimates that average daily indoor intakes of ozone oxidation products are roughly one-third to twice the indoor inhalation intake of ozone alone. Some of these oxidation products are known or suspected to adversely...... affect human health (e.g., formaldehyde, acrolein, hydro-peroxides, fine and ultrafine particles). Indirect evidence supports connections between morbidity/mortality and exposures to indoor ozone and its oxidation products. For example, cities with stronger associations between outdoor ozone...

  2. Acute effects of inhaled urban particles and ozone: lung morphology, macrophage activity, and plasma endothelin-1.

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    Bouthillier, L; Vincent, R; Goegan, P; Adamson, I Y; Bjarnason, S; Stewart, M; Guénette, J; Potvin, M; Kumarathasan, P

    1998-12-01

    We studied acute responses of rat lungs to inhalation of urban particulate matter and ozone. Exposure to particles (40 mg/m3 for 4 hours; mass median aerodynamic diameter, 4 to 5 microm; Ottawa urban dust, EHC-93), followed by 20 hours in clean air, did not result in acute lung injury. Nevertheless, inhalation of particles resulted in decreased production of nitric oxide (nitrite) and elevated secretion of macrophage inflammatory protein-2 from lung lavage cells. Inhalation of ozone (0.8 parts per million for 4 hours) resulted in increased neutrophils and protein in lung lavage fluid. Ozone alone also decreased phagocytosis and nitric oxide production and stimulated endothelin-1 secretion by lung lavage cells but did not modify secretion of macrophage inflammatory protein-2. Co-exposure to particles potentiated the ozone-induced septal cellularity in the central acinus but without measurable exacerbation of the ozone-related alveolar neutrophilia and permeability to protein detected by lung lavage. The enhanced septal thickening was associated with elevated production of both macrophage inflammatory protein-2 and endothelin-1 by lung lavage cells. Interestingly, inhalation of urban particulate matter increased the plasma levels of endothelin-1, but this response was not influenced by the synergistic effects of ozone and particles on centriacinar septal tissue changes. This suggests an impact of the distally distributed particulate dose on capillary endothelial production or filtration of the vasoconstrictor. Overall, equivalent patterns of effects were observed after a single exposure or three consecutive daily exposures to the pollutants. The experimental data are consistent with epidemiological evidence for acute pulmonary effects of ozone and respirable particulate matter and suggest a possible mechanism whereby cardiovascular effects may be induced by particle exposure. In a broad sense, acute biological effects of respirable particulate matter from ambient air

  3. Transcriptomic changes induced by acute ozone in resistant and sensitive Medicago truncatula accessions

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    Mahalingam Ramamurthy

    2008-04-01

    Full Text Available Abstract Background Tropospheric ozone, the most abundant air pollutant is detrimental to plant and animal health including humans. In sensitive plant species even a few hours of exposure to this potent oxidant (200–300 nL. L-1 leads to severe oxidative stress that manifests as visible cell death. In resistant plants usually no visible symptoms are observed on exposure to similar ozone concentrations. Naturally occurring variability to acute ozone in plants provides a valuable resource for examining molecular basis of the differences in responses to ozone. From our earlier study in Medicago truncatula, we have identified cultivar Jemalong is ozone sensitive and PI 464815 (JE154 is an ozone-resistant accession. Analyses of transcriptome changes in ozone-sensitive and resistant accession will provide important clues for understanding the molecular changes governing the plant responses to ozone. Results Acute ozone treatment (300 nL L-1 for six hours led to a reactive oxygen species (ROS burst in sensitive Jemalong six hours post-fumigation. In resistant JE154 increase in ROS levels was much reduced compared to Jemalong. Based on the results of ROS profiling, time points for microarray analysis were one hour into the ozone treatment, end of treatment and onset of an ozone-induced ROS burst at 12 hours. Replicated temporal transcriptome analysis in these two accessions using 17 K oligonucleotide arrays revealed more than 2000 genes were differentially expressed. Significantly enriched gene ontologies (GOs were identified using the Cluster Enrichment analysis program. A striking finding was the alacrity of JE154 in altering its gene expression patterns in response to ozone, in stark contrast to delayed transcriptional response of Jemalong. GOs involved in signaling, hormonal pathways, antioxidants and secondary metabolism were altered in both accessions. However, the repertoire of genes responding in each of these categories was different between

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

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    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.

  5. Acute Ozone-Induced Pulmonary and Systemic Metabolic Effects Are Diminished in Adrenalectomized Rats.

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    Miller, Desinia B; Snow, Samantha J; Schladweiler, Mette C; Richards, Judy E; Ghio, Andrew J; Ledbetter, Allen D; Kodavanti, Urmila P

    2016-04-01

    Acute ozone exposure increases circulating stress hormones and induces metabolic alterations in animals. We hypothesized that the increase of adrenal-derived stress hormones is necessary for both ozone-induced metabolic effects and lung injury. Male Wistar-Kyoto rats underwent bilateral adrenal demedullation (DEMED), total bilateral adrenalectomy (ADREX), or sham surgery (SHAM). After a 4 day recovery, rats were exposed to air or ozone (1 ppm), 4 h/day for 1 or 2 days and responses assessed immediately postexposure. Circulating adrenaline levels dropped to nearly zero in DEMED and ADREX rats relative to SHAM. Corticosterone tended to be low in DEMED rats and dropped to nearly zero in ADREX rats. Adrenalectomy in air-exposed rats caused modest changes in metabolites and lung toxicity parameters. Ozone-induced hyperglycemia and glucose intolerance were markedly attenuated in DEMED rats with nearly complete reversal in ADREX rats. Ozone increased circulating epinephrine and corticosterone in SHAM but not in DEMED or ADREX rats. Free fatty acids (P = .15) and branched-chain amino acids increased after ozone exposure in SHAM but not in DEMED or ADREX rats. Lung minute volume was not affected by surgery or ozone but ozone-induced labored breathing was less pronounced in ADREX rats. Ozone-induced increases in lung protein leakage and neutrophilic inflammation were markedly reduced in DEMED and ADREX rats (ADREX > DEMED). Ozone-mediated decreases in circulating white blood cells in SHAM were not observed in DEMED and ADREX rats. We demonstrate that ozone-induced peripheral metabolic effects and lung injury/inflammation are mediated through adrenal-derived stress hormones likely via the activation of stress response pathway.

  6. S-nitroso-proteome in poplar leaves in response to acute ozone stress.

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    Elisa Vanzo

    Full Text Available Protein S-nitrosylation, the covalent binding of nitric oxide (NO to protein cysteine residues, is one of the main mechanisms of NO signaling in plant and animal cells. Using a combination of the biotin switch assay and label-free LC-MS/MS analysis, we revealed the S-nitroso-proteome of the woody model plant Populus x canescens. Under normal conditions, constitutively S-nitrosylated proteins in poplar leaves and calli comprise all aspects of primary and secondary metabolism. Acute ozone fumigation was applied to elicit ROS-mediated changes of the S-nitroso-proteome. This treatment changed the total nitrite and nitrosothiol contents of poplar leaves and affected the homeostasis of 32 S-nitrosylated proteins. Multivariate data analysis revealed that ozone exposure negatively affected the S-nitrosylation status of leaf proteins: 23 proteins were de-nitrosylated and 9 proteins had increased S-nitrosylation content compared to the control. Phenylalanine ammonia-lyase 2 (log2[ozone/control] = -3.6 and caffeic acid O-methyltransferase (-3.4, key enzymes catalyzing important steps in the phenylpropanoid and subsequent lignin biosynthetic pathways, respectively, were de-nitrosylated upon ozone stress. Measuring the in vivo and in vitro phenylalanine ammonia-lyase activity indicated that the increase of the phenylalanine ammonia-lyase activity in response to acute ozone is partly regulated by de-nitrosylation, which might favor a higher metabolic flux through the phenylpropanoid pathway within minutes after ozone exposure.

  7. Combined anaerobic–ozonation process for treatment of textile wastewater: Removal of acute toxicity and mutagenicity

    Energy Technology Data Exchange (ETDEWEB)

    Punzi, Marisa, E-mail: marisa.punzi@biotek.lu.se [Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Nilsson, Filip [Water and Environmental Engineering at the Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Anbalagan, Anbarasan [Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Svensson, Britt-Marie [School of Education and Environment, Kristianstad University, SE-291 88 Kristianstad (Sweden); Jönsson, Karin [Water and Environmental Engineering at the Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Mattiasson, Bo; Jonstrup, Maria [Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden)

    2015-07-15

    Highlights: • COD and UV absorbance were effectively reduced. • The treated effluents were non-toxic to Artemia salina and Vibrio fischeri. • The real textile wastewater was mutagenic. • Mutagenicity persisted after bio treatment and even more after a short ozonation. • Higher ozone doses completely remove mutagenicity. - Abstract: A novel set up composed of an anaerobic biofilm reactor followed by ozonation was used for treatment of artificial and real textile effluents containing azo dyes. The biological treatment efficiently removed chemical oxygen demand and color. Ozonation further reduced the organic content of the effluents and was very important for the degradation of aromatic compounds, as shown by the reduction of UV absorbance. The acute toxicity toward Vibrio fischeri and the shrimp Artemia salina increased after the biological treatment. No toxicity was detected after ozonation with the exception of the synthetic effluent containing the highest concentration, 1 g/l, of the azo dye Remazol Red. Both untreated and biologically treated textile effluents were found to have mutagenic effects. The mutagenicity increased even further after 1 min of ozonation. No mutagenicity was however detected in the effluents subjected to longer exposure to ozone. The results of this study suggest that the use of ozonation as short post-treatment after a biological process can be beneficial for the degradation of recalcitrant compounds and the removal of toxicity of textile wastewater. However, monitoring of toxicity and especially mutagenicity is crucial and should always be used to assess the success of a treatment strategy.

  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. 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.

  10. The effect of ozone exposure on the release of eicosanoids in guinea-pig BAL fluid in relation to cellular damage and inflammation

    Directory of Open Access Journals (Sweden)

    H. J. M. Van Hoof

    1997-01-01

    Full Text Available The observed effects after ozone exposure strongly depend on ozone concentration and exposure time. We hypothesized that depending on the O3 exposure protocol, mainly either an oxidant damage or an inflammation will determine the O3 toxicity. We compared two different ozone exposure protocols: an acute exposure (3 ppm 2 h for studying the oxidant damage and an exposure (1 ppm 12 h where an inflammatory component is also probably involved. We measured LDH activity and protein and albumin exudation as markers for cellular damage. After the acute exposure an increase in LDH activity was measured and after exposure to 1 ppm ozone for 12 h the exudation of protein and albumin was also enhanced. The histological examinations showed a neutrophilic inflammatory response only after exposure to 1 ppm ozone for 12 h. The acute exposure protocol resulted in an increased release of PGE2, PGD2, PGF2α and 6-ketoPGF1α whereas exposure to 1 ppm ozone for 12 h led to an additional release of LTB4. No effects were measured on the release of TxB2 and LTC4/D4/E4. These changed amounts of eicosanoids will probably contribute to the ozone-induced lung function changes.

  11. Interannual Variability of Ozone and Ultraviolet Exposure

    Science.gov (United States)

    Herman, J. R.; Piacentini, R. D.; Ziemke, J.; Celarier, E.; Larko. D.

    1999-01-01

    Annual zonal averages of ozone amounts from Nimbus-7/TOMS (Total Ozone Mapping Spectrometer) (1979 to 1992) are used to estimate the interannual variability of ozone and UVB (290 - 315 nm) irradiance between plus or minus 60 deg. latitude. Clear-sky interannual ozone and UVB changes are mainly caused by the Quasi Biennial Oscillation (QBO) of stratospheric winds, and can amount to plus or minus 15% at 300 nm and plus or minus 5% at 310 nm (or erythemal irradiance) at the equator and at middle latitudes. Near the equator, the interannual variability of ozone amounts and UV irradiance caused by the combination of the 2.3 year QBO and annual cycles implies that there is about a 5-year periodicity in UVB variability. At higher latitudes, the appearance of the interannual UVB maximum is predicted by the QBO, but without the regular periodicity. The 5-year periodic QBO effects on UVB irradiance are larger than the currently evaluated long-term changes caused by the decrease in ozone amounts.

  12. Growth-stage dependent crop yield response to ozone exposure.

    Science.gov (United States)

    Younglove, T; McCool, P M; Musselman, R C; Kahl, M E

    1994-01-01

    Data from four crop yield-loss field trials were examined to determine if analysis using an imposed phenological weighting function based on seasonal growth stage would provide a more accurate indication of impact of ozone exposure. Alfalfa (Medicago sativa L. cv. Moapa 69), dry bean (Phaseolus vulgaris L. cv. California Dark Red kidney), fresh market and processing tomato (Lycopersicon esculentum Mill. cv. 6718 VF and VF-145-B7879, respectively) were grown at 9-11 ambient field plots within southern California comprising an ambient gradient of ozone. The growing season for each crop was artificially divided into 'quarters' composed of equal numbers of whole days and roughly corresponding to specific growth stages. Ozone exposure was calculated for each of these 'quarters' and regressed against final crop yield using 163 different exposure statistics. Weighting functions were developed using reciprocal residual mean square (1/RMS) or percentage of the best 100 exposure statistics of the 163 tested (TOP100) for each of the quarters. The third quarter of the alfalfa season was clearly most responsive to ozone as measured by both of the weighting functions. Third quarter ozone was also weighted highest by both weighting functions for dry bean. Fresh market and processing tomato were each influenced the greatest by second quartero zone as demonstrated by both weighting functions. The occurrence of ozone during physiologically important events (flowering and initial fruit set in second quarter for tomato; pod development in third quarter for dry bean) appeared to influence the yield of these crops the greatest. Growth-stage-dependent phenological weighting of pollutant exposure may result in more effective predictions of levels of ozone exposure resulting in yield reductions.

  13. 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

  14. Assessing the Influence of Indoor Exposure to "Outdoor Ozone" on the Relationship between Ozone and Short-term Mortality in US Communities

    DEFF Research Database (Denmark)

    Chen, Chun; Zhao, Bin; Weschler, Charles J.

    2012-01-01

    BACKGROUND: City-to-city differences have been reported for the increase in short-term mortality associated with a given increase in ozone concentration (ozone mortality coefficient). Although ozone concentrations are monitored at central outdoor locations, a large fraction of total ozone exposur......: Differences in ozone mortality coefficients among cities appear to partially reflect differences in total ozone exposure resulting from differences in the amount of outdoor ozone that is transported indoors....

  15. Combined anaerobic-ozonation process for treatment of textile wastewater: removal of acute toxicity and mutagenicity.

    Science.gov (United States)

    Punzi, Marisa; Nilsson, Filip; Anbalagan, Anbarasan; Svensson, Britt-Marie; Jönsson, Karin; Mattiasson, Bo; Jonstrup, Maria

    2015-07-15

    A novel set up composed of an anaerobic biofilm reactor followed by ozonation was used for treatment of artificial and real textile effluents containing azo dyes. The biological treatment efficiently removed chemical oxygen demand and color. Ozonation further reduced the organic content of the effluents and was very important for the degradation of aromatic compounds, as shown by the reduction of UV absorbance. The acute toxicity toward Vibrio fischeri and the shrimp Artemia salina increased after the biological treatment. No toxicity was detected after ozonation with the exception of the synthetic effluent containing the highest concentration, 1 g/l, of the azo dye Remazol Red. Both untreated and biologically treated textile effluents were found to have mutagenic effects. The mutagenicity increased even further after 1 min of ozonation. No mutagenicity was however detected in the effluents subjected to longer exposure to ozone. The results of this study suggest that the use of ozonation as short post-treatment after a biological process can be beneficial for the degradation of recalcitrant compounds and the removal of toxicity of textile wastewater. However, monitoring of toxicity and especially mutagenicity is crucial and should always be used to assess the success of a treatment strategy.

  16. Effects of ozone exposure: a comparison between oral and nasal breathing

    Energy Technology Data Exchange (ETDEWEB)

    Hynes, B.; Silverman, F.; Cole, P.; Corey, P.

    1988-09-01

    Mode of inhalation, by nose or by mouth, as a determinant of pulmonary toxicity to acute inhalant exposure has been investigated incompletely. This communication addresses whether there are significant differences in toxic pulmonary responses to acute ozone (O/sub 3/) exposure between differing modes of inhalation (nasal vs. oral breathing). Changes in the results of pulmonary function tests and symptomatology of healthy young adults were compared following both exclusive nose and exclusive mouth breathing during a 30-min exposure to approximately 0.4 ppm O/sub 3/ under conditions of moderate continuous exercise. In this single-blind, randomized, crossover study, no significant differences in either the results of pulmonary function tests or in symptomatology were found between the two modes of inhalation.

  17. Exposure of humans to ambient levels of ozone for 6. 6 hours causes cellular and biochemical changes in the lung

    Energy Technology Data Exchange (ETDEWEB)

    Devlin, R.B.; McDonnell, W.F.; Mann, R.; Becker, S.; House, D.E.; Schreinemachers, D.; Koren, H.S. (Environmental Protection Agency, Research Triangle Park, NC (USA))

    1991-01-01

    An acute (2 h) exposure of humans to 0.4 ppm ozone initiates biochemical changes in the lung that result in the production of components mediating inflammation and acute lung damage as well as components having the potential to lead to long-term effects such as fibrosis. However, many people are exposed to lower levels of ozone than this, but for periods of several hours. Therefore, it is important to determine if a prolonged exposure to low levels of ozone is also capable of causing cellular and biochemical changes in the lung. Nonsmoking males were randomly exposed to filtered air and either 0.10 ppm ozone or 0.08 ppm ozone for 6.6 h with moderate exercise (40 liters/min). Bronchoalveolar lavage (BAL) was performed 18 h after each exposure, and cells and fluid were analyzed. The BAL fluid of volunteers exposed to 0.10 ppm ozone had significant increases in neutrophils (PMNs), protein, prostaglandin E2 (PGE2), fibronectin, interleukin-6 (IL-6), and lactate dehydrogenase (LDH) compared with BAL fluid from the same volunteers exposed to filtered air. In addition, there was a decrease in the ability of alveolar macrophages to phagocytize yeast via the complement receptor. Exposure to 0.08 ppm ozone resulted in significant increases in PMNs, PGE2, LDH, IL-6, alpha 1-antitrypsin, and decreased phagocytosis via the complement receptor. However, BAL fluid protein and fibronectin were no longer significantly elevated. We conclude that exposure of humans to as low a level as 0.08 ppm for 6.6 h is sufficient to initiate an inflammatory reaction in the lung.

  18. 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.

  19. 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...

  20. 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 ...

  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. 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

    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......, was observed. Only the Spanish cities did not fit this pattern; there, ozone levels were again lower than in central European cities, probably due to the direct influence of strong car traffic emissions. In general, ozone concentrations and cumulative exposure were significantly higher at suburban sites than...

  3. Ozone Exposure System Designed and Used to High-Altitude Airship Materials

    Science.gov (United States)

    Miller, Sharon K.

    2005-01-01

    High-altitude airships can receive high doses of ozone over short mission durations. For example, in 1 year at an altitude of 70,000 ft, the ozone fluence (number arriving per unit area) can be as high as 1.2 1024 molecules/sq cm. Ozone exposure at these levels can embrittle materials or change the performance of solar cells. It is important to expose components and materials to the expected ozone dosage to determine if the ozone exposure could cause any mission-critical failures.

  4. Elevation of susceptibility to ozone-induced acute tracheobronchial injury in transgenic mice deficient in Clara cell secretory protein.

    Science.gov (United States)

    Plopper, C G; Mango, G W; Hatch, G E; Wong, V J; Toskala, E; Reynolds, S D; Tarkington, B K; Stripp, B R

    2006-05-15

    Increases in Clara cell abundance or cellular expression of Clara cell secretory protein (CCSP) may cause increased tolerance of the lung to acute oxidant injury by repeated exposure to ozone (O3). This study defines how disruption of the gene for CCSP synthesis affects the susceptibility of tracheobronchial epithelium to acute oxidant injury. Mice homozygous for a null allele of the CCSP gene (CCSP-/-) and wild type (CCSP+/+) littermates were exposed to ozone (0.2 ppm, 8 h; 1 ppm, 8 h) or filtered air. Injury was evaluated by light and scanning electron microscopy, and the abundance of necrotic, ciliated, and nonciliated cells was estimated by morphometry. Proximal and midlevel intrapulmonary airways and terminal bronchioles were evaluated. There was no difference in airway epithelial composition between CCSP+/+ and CCSP-/- mice exposed to filtered air, and exposure to 0.2 ppm ozone caused little injury to the epithelium of both CCSP+/+ and CCSP-/- mice. After exposure to 1.0 ppm ozone, CCSP-/- mice suffered from a greater degree of epithelial injury throughout the airways compared to CCSP+/+ mice. CCSP-/- mice had both ciliated and nonciliated cell injury. Furthermore, lack of CCSP was associated with a shift in airway injury to include proximal airway generations. Therefore, we conclude that CCSP modulates the susceptibility of the epithelium to oxidant-induced injury. Whether this is due to the presence of CCSP on the acellular lining layer surface and/or its intracellular distribution in the secretory cell population needs to be defined.

  5. Evaluation of ozone exposure indices in exposure-response modeling.

    Science.gov (United States)

    Lee, E H; Tingey, D T; Hogsett, W E

    1988-01-01

    In exposure-response modeling, a major concern is the numerical definition of exposure in relating crop loss to O3, yet few indices have been considered. This paper addresses research in which plant growth was regressed for soybean, wheat, cotton, corn, and sorghum against 613 numerical exposure indices using the Box-Tidwell model. When the minimum sum of squared errors criterion was used, optimum performance was not attained for any single index; however, near optimum performances were achieved by two censored cumulative indices and from a class of indices called the generalized, phenologically weighted, cumulative impact indices (GPWCIs). The top-performing GPWCIs accumulated concentrations, used sigmoid weighting schemes emphasizing O3 concentrations of 0.06 ppm (118 microg m(-3)) or higher, and had phenological weighting schemes with greatest weight occurring 20 to 40 days prior to crop maturity. These findings indicate that (1) peak concentrations are important, but lower concentrations should be included in the calculations, (2) increased plant sensitivity occurs between flowering and maturity, and (3) plants respond to cumulative exposure impact.

  6. 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...

  7. Long-Term Exposure to Ozone and Life Expectancy in the United States, 2002 to 2008.

    Science.gov (United States)

    Li, Chaoyang; Balluz, Lina S; Vaidyanathan, Ambarish; Wen, Xiao-Jun; Hao, Yongping; Qualters, Judith R

    2016-02-01

    Long-term exposure to ground-level ozone is associated with increased risk of morbidity and mortality. The association remains uncertain between long-term exposure to ozone and life expectancy. We assessed the associations between seasonal mean daily 8-hour maximum (8-hr max) ozone concentrations measured during the ozone monitoring seasons and life expectancy at birth in 3109 counties of the conterminous U.S. during 2002 to 2008. We used latent class growth analysis to identify latent classes of counties that had distinct mean levels and rates of change in ozone concentrations over the 7-year period and used linear regression analysis to determine differences in life expectancy by ozone levels. We identified 3 classes of counties with distinct seasonal mean daily 8-hr max ozone concentrations and rates of change. When compared with the counties with the lowest ozone concentrations, the counties with the highest ozone concentrations had 1.7- and 1.4-year lower mean life expectancy in males and females (both P life expectancy in males (95% CI: -0.30 to -0.19) and 0.21 year in females (95% CI: -0.25 to -0.17). We identified 3 classes of counties with distinct mean levels and rates of change in ozone concentrations. Our findings suggest that long-term exposure to a higher ozone concentration may be associated with a lower life expectancy.

  8. Impacts of summer ozone exposure on the growth and overwintering of UK upland vegetation

    Science.gov (United States)

    Hayes, Felicity; Mills, Gina; Williams, Philip; Harmens, Harry; Büker, Patrick

    The effects of ozone exposure on species of an upland grassland were assessed. Thirty-three species from Snowdonia, North Wales, UK, were exposed for 10 weeks to a weekly episodic ozone regime in solardomes representing predicted future concentrations. Two solardomes were used as controls, with ozone added to charcoal-filtered air to give a continuous ozone concentration of 30 ppb (O 3(30)). A weekly episodic ozone regime was applied to two other solardomes, with concentrations rising for 8 h per day to 80 ppb on day 1, 100 ppb on days 2 and 3, and 80 ppb on day 4; ozone concentrations remained at 30 ppb at all other times (O 3(30+peaks)). The control and background ozone concentrations of 30 ppb were maintained throughout the night as well as during the daytime. During exposure to the episodic ozone regime, some species were sensitive to ozone and showed ozone-specific leaf injury symptoms (e.g . Carex echinata) and/or premature senescence (e.g. Festuca rubra) and/or changes in above-ground biomass (e.g. Armeria maritima), whereas other species (e.g Holcus lanatus and Carex demissa) showed no effects. Some species, although showing no effects during the 10-week ozone exposure, showed carry-over effects on biomass the following spring, after a winter period of ambient ozone exposure (e.g. Galium saxatile, Nardus stricta and Saxifraga stellaris). The carry-over effects shown in this study indicate the potential ecological impact of ozone on semi-natural vegetation species and indicate the importance of longer-term studies on the effects of ozone on plants.

  9. Duration of enhanced responsiveness upon re-exposure to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Schonfeld, B.R.; Adams, W.C.; Schelegle, E.S. (Univ. of California, Davis (USA))

    1989-07-01

    It has been repeatedly observed that ozone (O3) re-exposure within 24 h elicits enhanced pulmonary function responses. However, there are only limited observations concerning re-exposure to O3 at intervals between 24 h and several days. The present study was designed to assess the effects of re-exposure to 0.35 ppm O3 at intervals of 24, 48, 72, and 120 h. Forty young adult male subjects were assigned randomly to one of four groups in ascending order of time to re-exposure (groups 1-4). Each exercised on a bicycle ergometer for 60 min at a workload that elicited a mean ventilation of 60 l/min on three occasions: protocol 1 (P1), filtered air (FA); protocol 2 (P2), 0.35 ppm O3; and protocol 3 (P3), 0.35 ppm O3. In addition to standard pulmonary function measures, specific airway resistance (SRaw); exercise ventilatory pattern, i.e., respiratory frequency (fR) and tidal volume (VT); and subjective symptoms (SS) were assessed. Statistical analysis revealed significant differences (p less than .05) for all groups between the FA (P1) responses and those for the two O3 exposures (P2, P3) for forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1.0), SRaw, fR, VT, and SS. When the two O3 exposures (P2 and P3) were compared, only group 1 (24 h) responses were statistically significant upon re-exposure: FEV1.0, -16.1 vs. -30.4% (p less than .003); SRaw, 20.5 vs. 34.5% (p less than .05); fR, 44.2 vs. 65.3% (p less than .001); and SS (p less than .015).

  10. 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...

  11. 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.

  12. Does ozone exposure alter growth and carbon allocation of mycorrhizal plants

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, L.C.; Gamon, J.A. (California State Univ., Los Angeles, CA (United States)); Andersen, C.P. (Environmental Protection Agency, Corvallis, OR (United States))

    1994-06-01

    Ozone is known to adversely affect plant growth. However, it is less clear how ozone affects belowground processes. This study tests the hypothesis that ozone alters growth and carbon allocation of vesicular arbuscular mycorrhizal (VAM) plants. Two ecotypes of Elymus glaucus (blue wild rye) were exposed to mycorrhizal inoculation and episodic ozone exposures simulating atmospheric conditions in the Los Angeles Basin. Preliminary results show that effects of ozone on growth were subtle. In both ecotypes, growth of aboveground biomass was not affected by ozone while root growth was decreased. In most treatments, mycorrhizal inoculation decreased growth of leaves and stems, but had no significant effect on root growth. Three-way ANOVA tests indicated interactive effects between ecotype, mycorrhiza and ozone. Further experimental work is needed to reveal the biological processes governing these responses.

  13. Exposure to ozone reduces postharvest quality loss in red and green chilli peppers.

    Science.gov (United States)

    Glowacz, Marcin; Rees, Deborah

    2016-11-01

    The effect of continuous exposure to ozone at 0.45, 0.9 and 2μmolmol(-1) on quality changes during the storage of red and green chilli peppers at 10°C was investigated. Ozone at 0.45 and 0.9μmolmol(-1) reduced disease incidence in red peppers, with no further benefits at 2μmolmol(-1). Ozone at 0.9μmolmol(-1) reduced weight loss during storage and improved firmness maintenance. Skin colour was bleached in red peppers exposed to ozone at 2μmolmol(-1), and in green ones at all tested doses. Total phenolic content was not affected by ozone but antioxidant activity was reduced in green chilli peppers exposed to ozone at 2μmolmol(-1), due to lower ascorbic acid content in those samples. Ozone at 0.9μmolmol(-1) extended the shelf-life of chilli peppers.

  14. 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.

  15. Role of tachykinins in ozone-induced acute lung injury in guinea pigs

    Energy Technology Data Exchange (ETDEWEB)

    Tepper, J.S.; Costa, D.L.; Fitzgerald, S.; Doerfler, D.L.; Bromberg, P.A. (ManTech Environmental Technology, Inc., Research Triangle Park, NC (United States))

    1993-09-01

    To examine the hypothesis that the acute reversible changes caused by ozone (O3) exposure are mediated by tachykinin release, guinea pigs were depleted of tachykinins by use of repeated capsaicin (CAP) injections before O3 exposure in an attempt to prevent O3-induced functional changes. Unexpectedly, CAP pretreatment caused divergent results in the functional responses to O3. Ventilatory measurements obtained from CAP-pretreated O3-exposed (CAP-O3) animals were exacerbated rather than diminished compared with the effects of O3 alone. Similarly, lavage fluid protein accumulation was enhanced in the CAP-O3 group compared with the O3-exposed group. In better agreement with our initial hypothesis, the CAP-O3 group was less responsive than the O3-exposed animals to histamine aerosol challenge. Additionally, Evans blue dye accumulation, a hallmark of tachykinin release, was increased in O3-exposed animals and was partially blocked in the CAP-O3 group. These data suggest that tachykinin-containing sensory fibers are unlikely to mediate the acute effects of O3 exposure on tidal breathing and lavage fluid protein accumulation but may play a role in causing post-O3 airway hyperreactivity and protein extravasation into the trachea.

  16. 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.

  17. Acute ozone-induced differential gene expression profiles in rat lung.

    Science.gov (United States)

    Nadadur, Srikanth S; Costa, Daniel L; Slade, Ralph; Silbjoris, Robert; Hatch, Gary E

    2005-12-01

    Ozone is an oxidant gas that can directly induce lung injury. Knowledge of the initial molecular events of the acute O3 response would be useful in developing biomarkers of exposure or response. Toward this goal, we exposed rats to toxic concentrations of O3 (2 and 5 ppm) for 2 hr and the molecular changes were assessed in lung tissue 2 hr postexposure using a rat cDNA expression array containing 588 characterized genes. Gene array analysis indicated differential expression in almost equal numbers of genes for the two exposure groups: 62 at 2 ppm and 57 at 5 ppm. Most of these genes were common to both exposure groups, suggesting common roles in the initial toxicity response. However, we also identified the induction of nine genes specific to 2-ppm (thyroid hormone-beta receptor c-erb-A-beta; and glutathione reductase) or 5-ppm exposure groups (c-jun, induced nitric oxide synthase, macrophage inflammatory protein-2, and heat shock protein 27). Injury markers in bronchoalveolar lavage fluid (BALF) were used to assess immediate toxicity and inflammation in rats similarly exposed. At 2 ppm, injury was marked by significant increases in BALF total protein, N-acetylglucosaminidase, and lavageable ciliated cells. Because infiltration of neutrophils was observed only at the higher 5 ppm concentration, the distinctive genes suggested a potential amplification role for inflammation in the gene profile. Although the specific gene interactions remain unclear, this is the first report indicating a dose-dependent direct and immediate induction of gene expression that may be separate from those genes involved in inflammation after acute O3 exposure.

  18. Peri-implantation Ozone Exposure Alters Uterine Artery Flow and Induces Fetal Growth Restriction in Rats

    Science.gov (United States)

    Epidemiological studies suggest a relationship between air pollutant exposures to various adverse pregnancy outcomes. Elevated ambient ozone levels during the first and second trimesters have demonstrated an increased correlation to preeclampsia, gestational diabetes, and intraut...

  19. 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 ...

  20. Concentrations, cumulative exposure and critical levels of ozone in Ireland

    NARCIS (Netherlands)

    Kluizenaar, Y. de; Aherne, J.; Farrell, E.P.

    2001-01-01

    Concentrations of tropospheric ozone (O3) and exceedance of critical levels to vegetation have been investigated and mapped for Ireland. Hourly ozone concentration data (1995–1997) at 7 seven monitoring stations and the CORINE landcover database, supported by a Geographical Information System, were

  1. Studying cumulative ozone exposures in Europe during a 7-year period

    Science.gov (United States)

    Bastrup-Birk, Annemarie; Brandt, JøRgen; Zlatev, Zahari; Uria, Ignacio

    1997-10-01

    Ozone is one of the most harmful pollutants in the troposphere. High ozone concentrations can damage plants, animals and humans. The damaging effects depend on the magnitude of a critical level of a special parameter, the cumulative ozone exposure. This is why cumulative ozone exposures must be carefully studied. It is important to determine the relationships between relevant emissions (NOx emissions, human-made VOC emissions, and/or a combination of NOx emissions and human-made VOC emissions) and cumulative ozone exposures. All these issues are discussed in this paper. Meteorological data from seven consecutive years, from 1989 to 1995, have been used in the experiments with different scenarios for varying the emissions (the NOx emissions, the human-made VOC emissions, as well as both the NOx emissions and the human-made VOC emissions). The particular air pollution model used in this study is the Danish Eulerian Model. Several hundred runs with different input data (meteorological data and/or emission data) have been performed. Advanced visualization techniques are used to interpret the large amount of digital data collected in these runs and to show clearly different trends and relationships that are normally hidden behind millions and millions of numbers. The model results were compared with measurements taken at more than 80 stations located in different European countries. The experiments indicate that it is sufficient to carry out computations over 5 consecutive years in order to eliminate the influence of extreme meteorological conditions (very warm or very cold summer months) on the cumulative ozone exposures, while this effect is clearly seen if less than 5 years are used in the experiments. It is shown that the relationship between the emissions (NOx and/or human-made VOC emissions) and the cumulative ozone exposures is in general nonlinear. Finally, it is illustrated that the critical values for ozone exposures are exceeded in most of Europe (in many

  2. Responses of subjects with chronic obstructive pulmonary disease after exposures to 0. 3 ppm ozone

    Energy Technology Data Exchange (ETDEWEB)

    Kehrl, H.R.; Hazucha, M.J.; Solic, J.J.; Bromberg, P.A.

    1985-05-01

    The authors previously reported that the respiratory mechanics of intermittently exercising persons with chronic obstructive pulmonary disease (COPD) were unaffected by a 2-h exposure to 0.2 ppm ozone. Employing a single-blind, cross-over design protocol, 13 white men with nonreversible COPD (9 current smokers; mean FEV1/FVC, 56%) were randomly exposed on 2 consecutive days for 2 h to air and 0.3 ppm ozone. During exposures, subjects exercised (minute ventilation, 26.4 +/- 3.0 L/min) for 7.5 min every 30 min; ventilation and gas exchange measured during exercise showed no difference between exposure days. Pulmonary function tests (spirometry, body plethysmography) obtained before and after exposures were unchanged on the air day. On the ozone day the mean airway resistance and specific airway resistance showed the largest (25 and 22%) changes (p = 0.086 and 0.058, respectively). Arterial oxygen saturation (SaO/sub 2/) obtained in 8 subjects during the last exercise interval showed a mean decrement of 0.95% on the ozone exposure day; this change did not attain significance (p = 0.074). Nevertheless, arterial oxygen desaturation may be a true consequence of low-level ozone exposure in this compromised patient group. As normal subjects undergoing exposures to ozone with slightly higher exercise intensities show a threshold for changes in their respiratory mechanics at approximately 0.3 ppm, these data indicate that persons with COPD are not unduly sensitive to the effects of low-level ozone exposure.

  3. In Vivo Nanodetoxication for Acute Uranium Exposure

    Directory of Open Access Journals (Sweden)

    Luis Guzmán

    2015-06-01

    Full Text Available Accidental exposure to uranium is a matter of concern, as U(VI is nephrotoxic in both human and animal models, and its toxicity is associated to chemical toxicity instead of radioactivity. We synthesized different PAMAM G4 and G5 derivatives in order to prove their interaction with uranium and their effect on the viability of red blood cells in vitro. Furthermore, we prove the effectiveness of the selected dendrimers in an animal model of acute uranium intoxication. The dendrimer PAMAM G4-Lys-Fmoc-Cbz demonstrated the ability to chelate the uranyl ion in vivo, improving the biochemical and histopathologic features caused by acute intoxication with uranium.

  4. 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.

  5. Response of Phaseolus vulgaris L. to differing ozone regimes having identical total exposure

    Science.gov (United States)

    Musselman, Robert C.; Younglove, Theodore; McCool, Patrick M.

    Protocols were designed to test for differences in response of plants to ozone treatments having equal total exposure (concentration × time) but different exposure profiles Kidney beans ( Phaseolus vulgaris L., cv. California Dark Red) were exposed to ozone in controlled fumigation chambers within a greenhouse Four different ozone exposure profiles were used, each having the same total cumulative exposure (SUM00) and the same 7, 12 and 24 h seasonal means. The three exposure profiles which incorporated peak concentrations more severely impacted response parameters compared to a steady-state profile which did not exceed the National Ambient Air Quality Standard. Significant differences were found in percent necrotic leaf area, number of pods and top dry weight between exposure profiles. In additional analyses, the response parameters were regressed against seasonal cumulative ozone concentrations raised to powers of 0.33 and from 0.5 to 4 in steps of 0.5 in order to increase effective weighting of the higher concentrations. Total dry weight and leaf necrosis were best fit with the sum of the squared concentrations ( n = 2) while number of pods was best fit by the summed concentrations to the 3.5 power ( n = 3.5). These analyses suggest the peak ozone concentrations are important in determining plant response.

  6. 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.

  7. Acute effects of 0. 2 ppm ozone in patients with chronic obstructive pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Solic, J.J.; Hazucha, M.J.; Bromberg, P.A.

    1982-06-01

    Epidemiologic data suggest that patients with chronic obstructive pulmonary disease (COPD) might be more sensitive than normal persons to the respiratory effects of oxidant pollutant exposure. Our study was designed to determine the response of patients with COPD to ozone. Thirteen white men with nonreversible airways obstruction (mean FEV1/FVC, 58%), of whom 8 were current smokers, were randomly exposed for 2 h to air and to 0.2 ppm ozone on 2 consecutive days using a single-blind crossover design. During either exposure, subjects exercised for 7.5 min every 30 min. Measures of respiratory mechanics obtained pre-exposure and postexposure were not significantly affected by either exposure. Similarly, ventilation and gas exchange measured during exercise showed no difference either between exercise periods or exposure days. However, arterial O/sub 2/ saturation (SaO/sub 2/), measured by ear oximetry during the final exercise period each day was lower (94.8%) at the end of O/sub 2/ exposure, than SaO/sub 2/ obtained at the end of air exposure (95.3%), the difference (0.48%) being significant (p . 0.008). Because normal subjects undergoing comparable exposures show a threshold for respiratory mechanical effects at about 0.3 ppm ozone, our data suggest that mild to moderate COPD is not associated with increased sensitivity to low ozone concentrations. However, our data do not rule out the possibility that the response of such subjects might be exaggerated at higher ozone concentrations. The consistent (in 11 of 13 subjects), though small, decrease in SaO/sub 2/ may indicate that indexes of ventilation/perfusion distribution might be more sensitive measures of ozone effect in this compromised patient group than are conventional respiratory mechanics measures.

  8. Therapeutic effects of topical application of ozone on acute cutaneous wound healing.

    Science.gov (United States)

    Kim, Hee Su; Noh, Sun Up; Han, Ye Won; Kim, Kyoung Moon; Kang, Hoon; Kim, Hyung Ok; Park, Young Min

    2009-06-01

    This study was undertaken to evaluate the therapeutic effects of topical ozonated olive oil on acute cutaneous wound healing in a guinea pig model and also to elucidate its therapeutic mechanism. After creating full-thickness skin wounds on the backs of guinea pigs by using a 6 mm punch biopsy, we examined the wound healing effect of topically applied ozonated olive oil (ozone group), as compared to the pure olive oil (oil group) and non-treatment (control group). The ozone group of guinea pig had a significantly smaller wound size and a residual wound area than the oil group, on days 5 (Pozone group than that in the oil group on day 7. Immunohistochemical staining demonstrated upregulation of platelet derived growth factor (PDGF), transforming growth factor-beta (TGF-beta) and vascular endothelial growth factor (VEGF) expressions, but not fibroblast growth factor expression in the ozone group on day 7, as compared with the oil group. In conclusion, these results demonstrate that topical application of ozonated olive oil can accelerate acute cutaneous wound repair in a guinea pig in association with the increased expression of PDGF, TGF-beta, and VEGF.

  9. Ozone Induced Impairment of Systemic Metabolic Processes: Influence of Prior Ozone Exposure and Metformin Pre-treatment on Aged Wistar Kyoto (WKY) Rats.

    Science.gov (United States)

    SOT2014 Abstract for presentation: March 23-27, 2014; Phoenix, AZ Ozone Induced Impairment of Systemic Metabolic Processes: Influence of Prior Ozone Exposure and Metformin Pre-treatment on Aged Wistar Kyoto (WKY) Rats. V. Bass, D. Andrews, J. Richards, M. Schladweiler, A. Ledb...

  10. Ozone Induced Impairment of Systemic Metabolic Processes: Influence of Prior Ozone Exposure and Metformin Pre-treatment on Aged Wistar Kyoto (WKY) Rats.

    Science.gov (United States)

    SOT2014 Abstract for presentation: March 23-27, 2014; Phoenix, AZ Ozone Induced Impairment of Systemic Metabolic Processes: Influence of Prior Ozone Exposure and Metformin Pre-treatment on Aged Wistar Kyoto (WKY) Rats. V. Bass, D. Andrews, J. Richards, M. Schladweiler, A. Ledb...

  11. Mapping acute systemic effects of inhaled particulate matter and ozone: multiorgan gene expression and glucocorticoid activity.

    Science.gov (United States)

    Thomson, Errol M; Vladisavljevic, Djordje; Mohottalage, Susantha; Kumarathasan, Prem; Vincent, Renaud

    2013-09-01

    Recent epidemiological studies have demonstrated associations between air pollution and adverse effects that extend beyond respiratory and cardiovascular disease, including low birth weight, appendicitis, stroke, and neurological/neurobehavioural outcomes (e.g., neurodegenerative disease, cognitive decline, depression, and suicide). To gain insight into mechanisms underlying such effects, we mapped gene profiles in the lungs, heart, liver, kidney, spleen, cerebral hemisphere, and pituitary of male Fischer-344 rats immediately and 24h after a 4-h exposure by inhalation to particulate matter (0, 5, and 50mg/m(3) EHC-93 urban particles) and ozone (0, 0.4, and 0.8 ppm). Pollutant exposure provoked differential expression of genes involved in a number of pathways, including antioxidant response, xenobiotic metabolism, inflammatory signalling, and endothelial dysfunction. The mRNA profiles, while exhibiting some interorgan and pollutant-specific differences, were remarkably similar across organs for a set of genes, including increased expression of redox/glucocorticoid-sensitive genes and decreased expression of inflammatory genes, suggesting a possible hormonal effect. Pollutant exposure increased plasma levels of adrenocorticotropic hormone and the glucocorticoid corticosterone, confirming activation of the hypothalamic-pituitary-adrenal axis, and there was a corresponding increase in markers of glucocorticoid activity. Although effects were transient and presumably represent an adaptive response to acute exposure in these healthy animals, chronic activation and inappropriate regulation of the hypothalamic-pituitary-adrenal axis are associated with adverse neurobehavioral, metabolic, immune, developmental, and cardiovascular effects. The experimental data are consistent with epidemiological associations of air pollutants with extrapulmonary health outcomes and suggest a mechanism through which such health effects may be induced.

  12. Assessing the risk of chronic lung injury attributable to long-term ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Whitfield, R.G. (Argonne National Lab., IL (United States). Environmental Assessment and Information Sciences Div.); Wallsten, T.S. (North Carolina Univ., Chapel Hill, NC (United States). L.L. Thurstone Psychometric Lab.); Winkler, R.L. (Duke Univ., Durham, NC (United States). Fuqua School of Business); Richmond, H.M. (Environmental Protection Agency, Research Triangle Park, NC (United States). O

    1991-07-01

    The research described here is part of a larger risk assessment project sponsored by the US Environmental Protection Agency. The purpose of this research is to characterize scientific judgment regarding the risk of chronic lung injury to children aged 8 through 16 and adult outdoor workers due to long-term ozone exposure in areas with patterns of exposure similar to those found in southern California and the Northeast. The qualitative and quantitative judgments resulting from the work will not be used in the ongoing review of the ozone primary ambient air quality standard. They will instead be used to inform policymakers and the public about the possible health implications of long-term exposure to ozone. Our measure of injury is the incidence of mild or moderate lesions in the centriacinar region of the lung. The probabilities over population response rates were elicited from six health experts actively researching ozone-induced lung injury. We describe our approach and present the results in the form of judgmental probability distributions and associated qualitative comments over the population response rates for formation of lesions induced by exposure to ozone. 19 refs., 15 figs., 1 tab.

  13. 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, Pseud

  14. Changes in the expression of NO synthase isoforms after ozone: the effects of allergen exposure

    Directory of Open Access Journals (Sweden)

    Lee June-Hyuk

    2004-06-01

    Full Text Available Abstract Background The functional role of nitric oxide (NO and various nitric oxide synthase (NOS isoforms in asthma remains unclear. Objective This study investigated the effects of ozone and ovalbumin (OVA exposure on NOS isoforms. Methods The expression of inducible NOS (iNOS, neuronal NOS (nNOS, and endothelial NOS (eNOS in lung tissue was measured. Enhanced pause (Penh was measured as a marker of airway obstruction. Nitrate and nitrite in bronchoalveolar lavage (BAL fluid were measured using a modified Griess reaction. Results The nitrate concentration in BAL fluid from the OVA-sensitized/ozone-exposed/OVA-challenged group was greater than that of the OVA-sensitized/saline-challenged group. Methacholine-induced Penh was increased in the OVA-sensitized/ozone-exposed/OVA-challenged group, with a shift in the dose-response curve to the left, compared with the OVA-sensitized/saline-challenged group. The levels of nNOS and eNOS were increased significantly in the OVA-sensitized/ozone-exposed/OVA-challenged group and the iNOS levels were reduced compared with the OVA-sensitized/saline-challenged group. Conclusion In mice, ozone is associated with increases in lung eNOS and nNOS, and decreases in iNOS. None of these enzymes are further affected by allergens, suggesting that the NOS isoforms play different roles in airway inflammation after ozone exposure.

  15. Reversion by ozone treatment of acute nephrotoxicity induced by cisplatin in rats

    Directory of Open Access Journals (Sweden)

    Ricardo González

    2004-01-01

    Full Text Available BACKGROUND: Ozone therapy has become a useful treatment for pathological processes, in which the damage mediated by reactive oxygen species is involved. Several lines of evidence suggest that cisplatin-induced acute nephrotoxicity is partially mediated by reactive oxygen species.

  16. Comparison of ozone exposure characteristics in forested regions near Mexico City and Los Angeles

    Science.gov (United States)

    Miller, Paul R.; de Lourdes de Bauer, María; Quevedo Nolasco, Abel; Hernández Tejeda, Tomás

    This comparison of forest exposure to ozone in the vicinity of México City and Los Angeles provides preliminary evidence of the seasonal differences in ozone concentrations. Summer concentrations near México City are not as high as those near Los Angeles because most of the precipitation and associated cloudiness occurs near México City during the months of June through September. Winter concentrations remain nearly as high as summer concentrations at México City, because in winter skies are clearer and incident sunlight remains high. Latitudinal influences on solar zenith angle and the higher altitude of the México City region both contribute to a higher actinic flux than in the Los Angeles region. The primary difference in forest exposure is that there is very little respite from adverse ozone concentrations during the entire year in the México City region. Also, the rainy summer season would likely diminish water stress and result in greater ozone uptake at the Desierto de los Leones compared to dry summer conditions in California. The closer proximity of the Desierto de los Leones monitoring site to the urban area also contributes to high winter exposures. There is some respite from exposure during the winter in the San Bernardino mountain region; however, summer concentrations are higher than near México City. The greater transport distance from the Los Angeles source region also contributes to lower winter exposures.

  17. Immunotoxic effects of low level ozone exposure suggestive of an inducers in bronchial hyperresponiveness

    Institute of Scientific and Technical Information of China (English)

    SongH; LiDM

    2002-01-01

    For the city pollution of motor vehicle emissions,public air oxidizer exposure level has increasing tendence.As a representative of osidizer,ozone exposure is universal expecially at low levels in big city.Summarizing previous experimental study,which focuses on the exposure concentration at 0.125 ppm,the changes in inflammatory cytokines in animal airway suggest that low levels ozone expose activate cytokines resembling the bronchial hyperresponsiveness of atopy.Similarly the epidemiological study on adverse effects of ambient ozone exposure showed that the lower maxinal mid-expiratory flow of achoold children in exposed area where the concentration of ozone exceeded background levels only in the periphery of petroleum chemical enterprise were observed compared with those in control ares(P<0.05).This phenomenon of airway resistance increases as well as laboratory observation suggests that low level oxidizer exposure is one of the main risk factors of result in the increasing incidence of asthma in cities.

  18. Exposure to medium and high ambient levels of ozone causes adverse systemic inflammatory and cardiac autonomic effects.

    Science.gov (United States)

    Arjomandi, Mehrdad; Wong, Hofer; Donde, Aneesh; Frelinger, Jessica; Dalton, Sarah; Ching, Wendy; Power, Karron; Balmes, John R

    2015-06-15

    Epidemiological evidence suggests that exposure to ozone increases cardiovascular morbidity. However, the specific biological mechanisms mediating ozone-associated cardiovascular effects are unknown. To determine whether short-term exposure to ambient levels of ozone causes changes in biomarkers of cardiovascular disease including heart rate variability (HRV), systemic inflammation, and coagulability, 26 subjects were exposed to 0, 100, and 200 ppb ozone in random order for 4 h with intermittent exercise. HRV was measured and blood samples were obtained immediately before (0 h), immediately after (4 h), and 20 h after (24 h) each exposure. Bronchoscopy with bronchoalveolar lavage (BAL) was performed 20 h after exposure. Regression modeling was used to examine dose-response trends between the endpoints and ozone exposure. Inhalation of ozone induced dose-dependent adverse changes in the frequency domains of HRV across exposures consistent with increased sympathetic tone [increase of (parameter estimate ± SE) 0.4 ± 0.2 and 0.3 ± 0.1 in low- to high-frequency domain HRV ratio per 100 ppb increase in ozone at 4 h and 24 h, respectively (P = 0.02 and P = 0.01)] and a dose-dependent increase in serum C-reactive protein (CRP) across exposures at 24 h [increase of 0.61 ± 0.24 mg/l in CRP per 100 ppb increase in ozone (P = 0.01)]. Changes in HRV and CRP did not correlate with ozone-induced local lung inflammatory responses (BAL granulocytes, IL-6, or IL-8), but changes in HRV and CRP were associated with each other after adjustment for age and ozone level. Inhalation of ozone causes adverse systemic inflammatory and cardiac autonomic effects that may contribute to the cardiovascular mortality associated with short-term exposure.

  19. 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.

  20. Human Ozone (O3) Exposure Alters Serum Profile of Lipid Metabolites

    Science.gov (United States)

    HUMAN OZONE (O3) EXPOSURE ALTERS SERUM PROFILE OF LIPID METABOLITES Miller, D B.1; Kodavanti, U P.2 Karoly, E D.3; Cascio W.E2, Ghio, A J. 21. UNC-Chapel Hill, Chapel Hill, N.C., United States. 2. NHEERL, U.S. EPA, RTP, N.C., United States. 3. METABOLON INC., Durham, N.C., United...

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

    Science.gov (United States)

    Exposure to oxidant air pollution is associated with Increased respiratory morbiditses 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 pri...

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

    Energy Technology Data Exchange (ETDEWEB)

    Diffey, Brian [Regional Medical Physics Department, Newcastle General Hospital, Newcastle NE4 6BE (United Kingdom)

    2004-01-07

    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)

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

    Science.gov (United States)

    Diffey, Brian

    2004-01-07

    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.

  4. Human Ozone (O3) Exposure Alters Serum Profile of Lipid Metabolites

    Science.gov (United States)

    HUMAN OZONE (O3) EXPOSURE ALTERS SERUM PROFILE OF LIPID METABOLITES Miller, D B.1; Kodavanti, U P.2 Karoly, E D.3; Cascio W.E2, Ghio, A J. 21. UNC-Chapel Hill, Chapel Hill, N.C., United States. 2. NHEERL, U.S. EPA, RTP, N.C., United States. 3. METABOLON INC., Durham, N.C., United...

  5. 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...

  6. Increase in markers of airway inflammation after ozone exposure can be observed also in stable treated asthmatics with minimal functional response to ozone

    Directory of Open Access Journals (Sweden)

    Dente Federico L

    2010-01-01

    Full Text Available Abstract Background The discrepancy between functional and inflammatory airway response to ozone has been reported in normal subjects, but few data are available for stable asthmatics regularly treated with inhaled corticosteroids. Methods Twenty-three well controlled, regularly treated, mild-to-moderate asthmatic patients underwent two sequential randomised exposures to either filtered air or ozone (0.3 ppm for 2 hours in a challenge chamber. Pulmonary function (PF was monitored, and patients with FEV1 decrease greater than 10% from pre-challenge value were considered as responders. Immediately after each exposure, exhaled breath condensate (EBC was collected to measure malondialdehyde (MDA. Six hours after each exposure, PF and EBC collection were repeated, and sputum was induced to measure inflammatory cell counts and soluble mediators (IL-8 and neutrophil elastase. The response to ozone was also evaluated according to the presence of polymorphism in oxidative stress related NQO1 and GSTM1 genes. Results After ozone exposure, sputum neutrophils significantly increased in responders (n = 8, but not in nonresponders (n = 15. Other markers of neutrophil activation in sputum supernatant and MDA in EBC significantly increased in all patients, but only in nonresponders the increase was significant. In nonresponders, sputum eosinophils also significantly increased after ozone. There was a positive correlation between ozone-induced FEV1 fall and increase in sputum neutrophils. No difference in functional or inflammatory response to ozone was observed between subjects with or without the combination of NQO1wt- GSTM1null genotypes. Conclusions Markers of neutrophilic inflammation and oxidative stress increase also in asthmatic subjects not responding to ozone. A greater functional response to ozone is associated with greater neutrophil airway recruitment in asthmatic subjects.

  7. Overview of ozone human exposure and health risk analyses used in the U.S. EPA's review of the ozone air quality standard.

    Energy Technology Data Exchange (ETDEWEB)

    Whitfield, R. G.

    1999-03-04

    This paper presents an overview of the ozone human exposure and health risk analyses developed under sponsorship of the U.S. Environmental Protection Agency (EPA). These analyses are being used in the current review of the national ambient air quality standards (NAAQS) for ozone. The analyses consist of three principal steps: (1) estimating short-term ozone exposure for particular populations (exposure model); (2) estimating population response to exposures or concentrations (exposure-response or concentration-response models); and (3) integrating concentrations or exposure with concentration-response or exposure-response models to produce overall risk estimates (risk model). The exposure model, called the probabilistic NAAQS exposure model for ozone (pNEM/03), incorporates the following factors: hourly ambient ozone concentrations; spatial distribution of concentrations; ventilation state of individuals at time of exposure; and movement of people through various microenvironments (e.g., outdoors, indoors, inside a vehicle) of varying air quality. Exposure estimates are represented by probability distributions. Exposure-response relationships have been developed for several respiratory symptom and lung function health effects, based on the results of controlled human exposure studies. These relationships also are probabilistic and reflect uncertainties associated with sample size and variability of response among subjects. The analyses also provide estimates of excess hospital admissions in the New York City area based on results from an epidemiology study. Overall risk results for selected health endpoints and recently analyzed air quality scenarios associated with alternative 8-hour NAAQS and the current 1-hour standard for outdoor children are used to illustrate application of the methodology.

  8. Changes in the proteome of juvenile European beech following three years exposure to free-air elevated ozone

    Directory of Open Access Journals (Sweden)

    Kerner R

    2011-04-01

    Full Text Available Tropospheric ozone, one of the most phytotoxic air pollutants, may specially impose in long-lived forest trees substantial reduction in productivity and biomass. European beech saplings grown in lysimeter around areas were used to monitor proteomic changes upon elevated ozone concentrations following four vegetation periods of exposure. A proteome study based on highly sensitive two-dimensional fluorescence difference gel electrophoresis (2-D DIGE was performed to identify protein changes in European beech, the most important deciduous tree in Central Europe. Main emphasis was on identifying differentially expressed proteins after long-time period of ozone exposure under natural conditions rather than short-term responses or reactions under controlled conditions. Our results clearly demonstrate a response of European beech saplings to long-term ozone fumigation at the protein level. We indicate changes in the protein abundance of 142 protein spots; among them 59 were increased and 83 decreased following three years of elevated ozone exposure. As the first step, 40 proteins were identified by a homology driven mass spectrometric approach. Some of the identified proteins have been previously described in the context of short-term ozone responses in plants, indicating, at least for certain cellular functions, the congruence of plant reactions following short- and long-term ozone exposure. Under elevated ozone exposure, abundance of proteins related to the Calvin cycle and photosynthetic electron transport chain were decreased whereas the abundance of proteins regarding the carbon metabolism/catabolism were increased.

  9. 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)

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

    Directory of Open Access Journals (Sweden)

    P. J. Nowack

    2015-11-01

    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 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.

  11. 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.

  12. Interaction of ozone exposure with airway hyperresponsiveness and inflammation induced by trimellitic anhydride in sensitized guinea pigs

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jian; Chung, K.Fan [National Heart & Lung Institute, London (United Kingdom)

    1997-09-01

    The effect of prior ozone (O{sub 3}) exposure on airway hyperresponsiveness and inflammation induced by trimellitic anhydride (TMA) has been investigated in TMA-sensitized guinea pigs. Airway responsiveness was measured as the concentration of acetylcholine needed to increase baseline lung resistance (RL) by 300% (PC300). Ozone (3 ppm, for 3 h) caused an increase in-log PC300 at 1 h after exposure, with return of -log PC300 to control levels at 8 h. Ozone also increased baseline RL at 8 h. TMA challenge increase -log PC300 in TMA-sensitized guinea pigs at 8 h after challenge from 3.85 {+-} 0.09 to 4.11 {+-} 0.09. Ozone exposure prior to TMA challenge prevented the induction of airway hyperresponsiveness with a mean -log PC300 of 3.51 {+-} 0.20, which was not different from that of control TMA-Sensitized group. Baseline RL was significantly higher in ozone-pretreated animals after TMA challenge when compared to those of either control or challenged with TMA alone. Ozone had no effect on TMA challenge-induced BAL eosinophilia and neutrophilia. We conclude that a single exposure to ozone inhibits the increase in airway responsiveness, but increases the bronchoconstrictor response induced by TMA in TMA-Sensitized guinea pigs; however, the inflammatory airway response to TMA is unchanged by preexposure to ozone. 29 refs., 2 figs., 1 tab.

  13. Lung collagen and elastin after ozone exposure in vitamin B-6-deficient rats

    Energy Technology Data Exchange (ETDEWEB)

    Myers, B.A.; Dubick, M.A.; Gerriets, J.E.; Reiser, K.M.; Last, J.A.; Rucker, R.B.

    1986-01-01

    The effects of vitamin B-6 deficiency and ozone exposure on selected features of connective tissue metabolism in lung were investigated in groups of weanling male rats fed one of three diets: B-6-supplemented, fed ad lib; B-6-deficient, fed ad lib; or B-6-supplemented, restricted to the food intake of deficient rats for 5 weeks. Also, perinatal rat pups were studied that were nursed from dams fed one of the 3 diets from parturition to day 15 of lactation. During the final week of each experiment, half of the rats in each of the groups were exposed to 0.64 ppm of ozone (23.5 h per day). The collagen and elastin content, collagen synthesis rate, total protein synthesis rate, and lysyloxidase activity of lungs were measured. Perinatal pups rendered vitamin B-6-deficient were particularly sensitive to ozone exposure (65% died as compared to fewer than 5% of the ad lib or food-restricted controls). When L-proline incorporation into collagen and total protein was investigated using lung minces, food restriction and B-6-deficiency resulted in about one-half the incorporation normally observed. Total lung lysyl oxidase activity was also decreased in B-6-deficient and food-restricted rats compared to B-6-supplemented rats fed ad lib. Exposure to ozone resulted in increased lysyl oxidase activity and collagen synthesis in lungs from B-6-supplemented rats, but such responses were not observed in B-6-deficient or food-restricted (FR) rats exposed to ozone.

  14. Inflammatory Cytokines and White Blood Cell Counts Response to Environmental Levels of Diesel Exhaust and Ozone Inhalation Exposures

    Science.gov (United States)

    Epidemiological observations of urban inhalation exposures to diesel exhaust (DE) and ozone (O3) have shown pre-clinical cardiopulmonary responses in humans. Identifying the key biological mechanisms that initiate these health bioindicators is difficult due to variability in envi...

  15. Ozone exposure thresholds and foliar injury on forest plants in Switzerland.

    Science.gov (United States)

    VanderHeyden, D; Skelly, J; Innes, J; Hug, C; Zhang, J; Landolt, W; Bleuler, P

    2001-01-01

    Canton Ticino in southern Switzerland is exposed to some of the highest concentrations of tropospheric ozone in Europe. During recent field surveys in Canton Ticino, foliar symptoms identical to those caused by ozone have been documented on native tree and shrub species. In Europe, the critical ozone level for forest trees has been defined at an AOT40 of 10 ppm.h O3 (10 ppm.h accumulated exposure of ozone over a threshold of 40 ppb) during daylight hours over a six-month growing season. The objective of this study was to determine the amount of ambient ozone required to induce visible foliar symptoms on various forest plant species in southern Switzerland. Species were grown within eight open-top chambers and four open plots at the Vivaio Lattecaldo Cantonal Forest Nursery in Ticino, Switzerland. Species differed significantly in terms of the ppb.h exposures needed to cause visible symptoms. The most to least symptomatic species grown within open-plots in this study rank as Prunus serotina, Salix viminalis, Vibrnum lantana, Rhamnus cathartica, Betula pendula, Rumex obtusifolius, Sambucus racemosa, Morus nigra, Prunus avium, Fraxinus excelsior, Rhamnus frangula, Alnus viridis, Fagus sylvatica and Acer pseudoplatanus. Similar rankings were obtained in the non-filtered chamber plots. The ranking of species sensitivity closely follows AOT values for the occurrence of initial symptoms and symptom progression across the remainder of the exposure season. Species that first showed evidence of foliar injury also demonstrated the most sensitivity throughout the growing season, with symptoms rapidly advancing over ca. 25-30% of the total plant leaf surfaces by the end of the observation period. Conversely, those species that developed symptoms later in the season had far less total injury to plant foliage by the end of the observation period (1.5 to < 5% total leaf area injured). The current European ambient ozone standard may be insufficient to protect native plant species

  16. Ozone co-exposure modifies cardiac function responses to fine and ultrafine particulate matter in mice

    Science.gov (United States)

    There is growing evidence from epidemiological studies that show acute exposure to particulate matter (PM) increases the risk of cardiovascular morbidity and mortality. Although the data supporting these findings are increasingly more convincing, the immediate impact of PM inhala...

  17. Effects of ambient and acute partial pressures of ozone on leaf net CO sub 2 assimilation of field-grown Vitis vinifera L

    Energy Technology Data Exchange (ETDEWEB)

    Roper, T.R.; Williams, L.E. (Univ. of California, Davis (USA) Kearney Agricultural Center, Parlier, CA (USA))

    1989-12-01

    Mature, field-grown Vitis vinifera L. grapevines grown in open-top chambers were exposed to either charcoal-filtered air or ambient ozone partial pressures throughout the growing season. Individual leaves also were exposed to ozone partial pressures of 0.2, 0.4, or 0.6 micropascals per pascal for 5 hours. No visual ozone damage was found on leaves exposed to any of the treatments. Chronic exposure to ambient O{sub 3} partial pressures reduced net CO{sub 2} assimilation rate (A) between 5 and 13% at various times throughout the season when compared to the filtered treatment. Exposure of leaves to 0.2 micropascals per pascal O{sub 3} for 5 hours had no significant effect on A; however, A was reduced 84% for leaves exposed to 0.6 micropascals per pascal O{sub 3} when compared to the controls after 5 hours. Intercellular CO{sub 2} partial pressure (c{sub i}) was lower for leaves exposed to 0.2 micropascals per pascal O{sub 3} when compared to the controls, while c{sub i} of the leaves treated with 0.6 micropascals per pascal of O{sub 3} increased during the fumigation. The long-term effects of ambient O{sub 3} and short-term exposure to acute levels of O{sub 3} reduced grape leaf photosynthesis due to a reduction in both stomatal and mesophyll conductances.

  18. Room temperature oxidation enhancement of porous Si(001) using ultraviolet{endash}ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, W.H.; Yamani, Z.; Abu Hassan, L.H.; Greene, J.E.; Nayfeh, M. [University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801 (United States); Hasan, M. [C. C. Cameron Applied Research Center and Department of Electrical Engineering, University of North Carolina, Charlotte, North Carolina 28223 (United States)

    1996-11-01

    The interaction of porous silicon (001) with ozone and ultraviolet (uv) was investigated at room temperature and ambient pressure. The O/Si atomic ratio in oxidized samples, as measured by Auger depth profiling, was similar to those measured from thermally oxidized samples. For long exposure times ({approx_gt}15 min), the O/Si ratio stayed constant throughout the porous layer, indicating full oxidation of the porous structure. Additionally, the carbon concentration decreased significantly in the uv{endash}ozone oxidized layers as compared to the untreated porous layers. Oxide layers up to 400 nm were measured. Fourier transform ir absorption measurements show both an increase in the oxygen concentration and a decrease in hydrogen concentration after oxidation. Photoluminescence data show that this method of oxidation quenches light emission from the porous layer. We believe that uv induced excitation of valence electrons results in higher reactivity and diffusion of oxygen and ozone as well as bond softening. The large volume of voids in the porous structure assist penetration of ozone and atomic oxygen throughout the porous structure while the narrow lateral dimensions of the Si skeleton requires a short diffusion length for full oxidation. {copyright} {ital 1996 American Institute of Physics.}

  19. Physiological effects of ozone exposure on De Colgar and Rechaiga II tomato (Solanum lycopersicum L.) cultivars.

    Science.gov (United States)

    Maamar, Benchohra; Maatoug, Mohamed; Iriti, Marcello; Dellal, Abdelkader; Ait hammou, Mohammed

    2015-08-01

    The sensitivity of two tomato (Solanum lycopersicum L.) cultivars, Rechaiga II and De Colgar, to 50, 80, and 100 ppb ozone (O3) exposures was assessed in fumigation chamber, during 4 h per day over a period of 7 days. The Rechaiga II variety was shown to be sensitive to the dose of 50 ppb, showing chlorotic spots on the adaxial leaf surface and alterations of some physiological parameters. During 1-week fumigation, ozone caused a decrease in stomatal conductance, chlorophylls a and b, total chlorophylls, and carotenoids, although soluble sugars and membrane integrity were significantly increased in fumigated plants compared to controls. This trend was similar for the three pollutant doses used in fumigation. The De Colgar tomato remained asymptomatic.

  20. Ozone-induced acute tracheobronchial epithelial injury: relationship to granulocyte emigration in the lung

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, D.M.; Hubbard, W.C.; Wong, V.; Wu, R.; Pinkerton, K.; Plopper, C.G. (California Primate Research Center, School of Veterinary Medicine, University of California, Davis (United States))

    1992-05-01

    To investigate the relationship between granulocyte emigration and epithelial injury in specific airway generations of the tracheobronchial tree following short-term ozone exposure, we exposed rhesus monkeys for 8 h to 0.00 (controls) or 0.96 ppm ozone with post-exposure periods of 1, 12, 24, 72, and 168 h in filtered air before necropsy. There were five control and three exposed monkeys for each of the post-exposure times for a total of 20 monkeys. Neutrophils isolated from peripheral blood and labeled with 111In-tropolonate were infused in the cephalic vein in unanesthetized monkeys (except the 1-h group) 4 to 5 h before necropsy. The trachea and microdissected bronchi (fourth and ninth generations) and respiratory bronchioles (fifteenth generation) from the right upper lobe of each monkey were examined by electron microscopy. Labeled neutrophil influx into lung tissue and bronchoalveolar lavage fluid (BALF) was maximal at 12 h and returned to baseline by 24 h after exposure. This was in contrast to total neutrophils in BALF, which were significantly elevated through 24 h after exposure but returned to baseline by 72 h. Lavage protein was significantly elevated at 24 h after exposure but was at control levels at all other times. Morphometric observations showed epithelial necrosis at 1 and 12 h in the trachea and bronchioles but continued to be observed in significant numbers at 24 h after exposure in bronchi. A significant increase in the labeling index of epithelial cells was observed at 12 h only in bronchi. Epithelial necrosis and repair was associated with the presence of granulocytes in the epithelium and interstitium of all airway levels. However, eosinophils were maximally increased in the epithelium and interstitium of bronchi at 24 h after exposure when epithelial necrosis was maximal in these airways and when lavage protein was significantly elevated.

  1. Early life ozone exposure results in dysregulated innate immune function and altered microRNA expression in airway epithelium.

    Science.gov (United States)

    Clay, Candice C; Maniar-Hew, Kinjal; Gerriets, Joan E; Wang, Theodore T; Postlethwait, Edward M; Evans, Michael J; Fontaine, Justin H; Miller, Lisa A

    2014-01-01

    Exposure to ozone has been associated with increased incidence of respiratory morbidity in humans; however the mechanism(s) behind the enhancement of susceptibility are unclear. We have previously reported that exposure to episodic ozone during postnatal development results in an attenuated peripheral blood cytokine response to lipopolysaccharide (LPS) that persists with maturity. As the lung is closely interfaced with the external environment, we hypothesized that the conducting airway epithelium of neonates may also be a target of immunomodulation by ozone. To test this hypothesis, we evaluated primary airway epithelial cell cultures derived from juvenile rhesus macaque monkeys with a prior history of episodic postnatal ozone exposure. Innate immune function was measured by expression of the proinflammatory cytokines IL-6 and IL-8 in primary cultures established following in vivo LPS challenge or, in response to in vitro LPS treatment. Postnatal ozone exposure resulted in significantly attenuated IL-6 mRNA and protein expression in primary cultures from juvenile animals; IL-8 mRNA was also significantly reduced. The effect of antecedent ozone exposure was modulated by in vivo LPS challenge, as primary cultures exhibited enhanced cytokine expression upon secondary in vitro LPS treatment. Assessment of potential IL-6-targeting microRNAs miR-149, miR-202, and miR-410 showed differential expression in primary cultures based upon animal exposure history. Functional assays revealed that miR-149 is capable of binding to the IL-6 3' UTR and decreasing IL-6 protein synthesis in airway epithelial cell lines. Cumulatively, our findings suggest that episodic ozone during early life contributes to the molecular programming of airway epithelium, such that memory from prior exposures is retained in the form of a dysregulated IL-6 and IL-8 response to LPS; differentially expressed microRNAs such as miR-149 may play a role in the persistent modulation of the epithelial innate

  2. Early life ozone exposure results in dysregulated innate immune function and altered microRNA expression in airway epithelium.

    Directory of Open Access Journals (Sweden)

    Candice C Clay

    Full Text Available Exposure to ozone has been associated with increased incidence of respiratory morbidity in humans; however the mechanism(s behind the enhancement of susceptibility are unclear. We have previously reported that exposure to episodic ozone during postnatal development results in an attenuated peripheral blood cytokine response to lipopolysaccharide (LPS that persists with maturity. As the lung is closely interfaced with the external environment, we hypothesized that the conducting airway epithelium of neonates may also be a target of immunomodulation by ozone. To test this hypothesis, we evaluated primary airway epithelial cell cultures derived from juvenile rhesus macaque monkeys with a prior history of episodic postnatal ozone exposure. Innate immune function was measured by expression of the proinflammatory cytokines IL-6 and IL-8 in primary cultures established following in vivo LPS challenge or, in response to in vitro LPS treatment. Postnatal ozone exposure resulted in significantly attenuated IL-6 mRNA and protein expression in primary cultures from juvenile animals; IL-8 mRNA was also significantly reduced. The effect of antecedent ozone exposure was modulated by in vivo LPS challenge, as primary cultures exhibited enhanced cytokine expression upon secondary in vitro LPS treatment. Assessment of potential IL-6-targeting microRNAs miR-149, miR-202, and miR-410 showed differential expression in primary cultures based upon animal exposure history. Functional assays revealed that miR-149 is capable of binding to the IL-6 3' UTR and decreasing IL-6 protein synthesis in airway epithelial cell lines. Cumulatively, our findings suggest that episodic ozone during early life contributes to the molecular programming of airway epithelium, such that memory from prior exposures is retained in the form of a dysregulated IL-6 and IL-8 response to LPS; differentially expressed microRNAs such as miR-149 may play a role in the persistent modulation of the

  3. 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

  4. 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.

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

    Science.gov (United States)

    Roy, S. Deb; Beig, G.; Ghude, Sachin D.

    2009-07-01

    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.

  6. Oxidative stress-dependent changes in immune responses and cell death in the substantia nigra after ozone exposure in rat

    Science.gov (United States)

    Rivas-Arancibia, Selva; Zimbrón, Luis Fernando Hernández; Rodríguez-Martínez, Erika; Maldonado, Perla D.; Borgonio Pérez, Gabino; Sepúlveda-Parada, María

    2015-01-01

    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. PMID:25999851

  7. Ozone-induced acute pulmonary fibrosis in rats. Prevention of increased rates of collagen synthesis by methylprednisolone

    Energy Technology Data Exchange (ETDEWEB)

    Hesterberg, T.W.; Last, J.A.

    1981-01-01

    The net rate of collagen synthesis by lung minces prepared from rats exposed for 7 days to ozone was increased in a dose-dependent manner severalfold above the net rate obtained with lung minces prepared from rats that had breathed only filtered air. Concurrent administration of methylprednisolone during the exposure to ozone prevented the increase in rate of collagen synthesis in a dose-dependent manner for each level of ozone tested. These results could be correlted with lower levels of inflammatory edema measured in the same steroid-treated rats as decreased wet weights of their right apical lung lobes.

  8. Low-temperature ozone exposure technique to modulate the stoichiometry of WOx nanorods and optimize the electrochromic performance

    Science.gov (United States)

    Lin, Feng; Li, Chi-Ping; Chen, Gang; Tenent, Robert C.; Wolden, Colin A.; Gillaspie, Dane T.; Dillon, Anne C.; Richards, Ryan M.; Engtrakul, Chaiwat

    2012-06-01

    A low-temperature ozone exposure technique was employed for the post-treatment of WOx nanorod thin films fabricated from hot-wire chemical vapor deposition (HWCVD) and ultrasonic spray deposition (USD) techniques. The resulting films were characterized with x-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, UV-vis-NIR spectroscopy and x-ray photoelectron spectroscopy (XPS). The stoichiometry and surface crystallinity of the WOx thin films were subsequently modulated upon ozone exposure and thermal annealing without particle growth. The electrochromic performance was studied in a LiClO4-propylene carbonate electrolyte, and the results suggest that the low-temperature ozone exposure technique is superior to the traditional high-temperature thermal annealing (employed to more fully oxidize the WOx). The optical modulation at 670 nm was improved from 35% for the as-deposited film to 57% for the film after ozone exposure at 150 °C. The coloration efficiency was improved and the switching speed to the darkened state was significantly accelerated from 18.0 s for the as-deposited film to 11.8 s for the film after the ozone exposure. The process opens an avenue for low-temperature and cost-effective manufacturing of electrochromic films, especially on flexible polymer substrates.

  9. Interaction of drought and ozone exposure on isoprene emission from extensively cultivated poplar.

    Science.gov (United States)

    Yuan, Xiangyang; Calatayud, Vicent; Gao, Feng; Fares, Silvano; Paoletti, Elena; Tian, Yuan; Feng, Zhaozhong

    2016-10-01

    The combined effects of ozone (O3 ) and drought on isoprene emission were studied for the first time. Young hybrid poplars (clone 546, Populus deltoides cv. 55/56 x P. deltoides cv. Imperial) were exposed to O3 (charcoal-filtered air, CF, and non-filtered air +40 ppb, E-O3 ) and soil water stress (well-watered, WW, and mild drought, MD, one-third irrigation) for 96 days. Consistent with light-saturated photosynthesis (Asat ), intercellular CO2 concentration (Ci ) and chlorophyll content, isoprene emission depended on drought, O3 , leaf position and sampling time. Drought stimulated emission (+38.4%), and O3 decreased it (-40.4%). Ozone increased the carbon cost per unit of isoprene emission. Ozone and drought effects were stronger in middle leaves (13th-15th from the apex) than in upper leaves (6th-8th). Only Asat showed a significant interaction between O3 and drought. When the responses were up-scaled to the entire-plant level, however, drought effects on total leaf area translated into around twice higher emission from WW plants in clean air than in E-O3 . Our results suggest that direct effects on plant emission rates and changes in total leaf area may affect isoprene emission from intensively cultivated hybrid poplar under combined MD and O3 exposure, with important feedbacks for air quality.

  10. BVOC responses to realistic nitrogen fertilization and ozone exposure in silver birch.

    Science.gov (United States)

    Carriero, G; Brunetti, C; Fares, S; Hayes, F; Hoshika, Y; Mills, G; Tattini, M; Paoletti, E

    2016-06-01

    Emission of BVOC (Biogenic Volatile Organic Compounds) from plant leaves in response to ozone exposure (O3) and nitrogen (N) fertilization is poorly understood. For the first time, BVOC emissions were explored in a forest tree species (silver birch, Betula pendula) exposed for two years to realistic levels of O3 (35, 48 and 69 ppb as daylight average) and N (10, 30 and 70 kg ha(-1) yr(-1), applied weekly to the soil as ammonium nitrate). The main BVOCs emitted were: α-pinene, β-pinene, limonene, ocimene, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) and hexanal. Ozone exposure increased BVOC emission and reduced total leaf area. The effect on emission was stronger when a short-term O3 metric (concentrations at the time of sampling) rather than a long-term one (AOT40) was used. The effect of O3 on total leaf area was not able to compensate for the stimulation of emission, so that responses to O3 at leaf and whole-plant level were similar. Nitrogen fertilization increased total leaf area, decreased α-pinene and β-pinene emission, and increased ocimene, hexanal and DMNT emission. The increase of leaf area changed the significance of the emission response to N fertilization for most compounds. Nitrogen fertilization mitigated the effects of O3 exposure on total leaf area, while the combined effects of O3 exposure and N fertilization on BVOC emission were additive and not synergistic. In conclusion, O3 exposure and N fertilization have the potential to affect global BVOC via direct effects on plant emission rates and changes in leaf area.

  11. 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.

  12. Variation in glutathione and ascorbic acid content among selected cultivars of Phaseolus vulgaris prior to and after exposure to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Guri, A.

    1983-07-01

    Measurements of reduced glutathione (GSH) and ascorbic acid (AA) concentrations in the primary leaves of of four bean cultivars, two ozone-insensitive (S) and two ozone-sensitive (I), have revealed that GSH concentrations were not significantly different in all four cultivars prior to the exposure to ozone (0.28-0.32 ppm for 8 h); however, after ozone exposure GSH concentrations were significantly lower in the two sensitive cultivars, PHR and 0669, while in the two insensitive tolerants, FH and Nep-2, the drop in GSH concentrations was slight. The assay of glutathione reductase(GR), the enzyme which catalyzed the reduction of oxidized glutathione (GSSG) to its reduced form, namely GSH, indicated that its specific activity in the two insensitive cultivars was almost twice as high as in the two sensitive cultivars. The drop in AA concentration after 8 h of fumigation was moderate (although significant) in all four cultivars, whereas the concentrations of AA in all four cultivars prior to ozone fumigation were not significantly different. From the data it is suggested that differences in GR-specific activity, probably due to different isozymes, could be the reason for insensitivity or sensitivity to ozone among bean cultivars. 21 references, 3 tables.

  13. Acute and delayed effects of intermittant ozone on cardiovascular and thermoregulatory responses of young and aged rats

    Science.gov (United States)

    Ozone (03) is associated with cardiovascular and respiratory diseases. The aged population is considered to be more sensitive to air pollutants but relatively few studies have demonstrated increased susceptibility in animal models of aging. To study the acute and delayed physiolo...

  14. Premature mortality in India due to PM2.5 and ozone exposure

    Science.gov (United States)

    Ghude, Sachin D.; Chate, D. M.; Jena, C.; Beig, G.; Kumar, R.; Barth, M. C.; Pfister, G. G.; Fadnavis, S.; Pithani, Prakash

    2016-05-01

    This bottom-up modeling study, supported by new population census 2011 data, simulates ozone (O3) and fine particulate matter (PM2.5) exposure on local to regional scales. It quantifies, present-day premature mortalities associated with the exposure to near-surface PM2.5 and O3 concentrations in India using a regional chemistry model. We estimate that PM2.5 exposure leads to about 570,000 (CI95: 320,000-730,000) premature mortalities in 2011. On a national scale, our estimate of mortality by chronic obstructive pulmonary disease (COPD) due to O3 exposure is about 12,000 people. The Indo-Gangetic region accounts for a large part (~42%) of the estimated mortalities. The associated lost life expectancy is calculated as 3.4 ± 1.1 years for all of India with highest values found for Delhi (6.3 ± 2.2 years). The economic cost of estimated premature mortalities associated with PM2.5 and O3 exposure is about 640 (350-800) billion USD in 2011, which is a factor of 10 higher than total expenditure on health by public and private expenditure.

  15. Modulation of human alveolar macrophage properties by ozone exposure in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Becker, S.; Madden, M.C.; Newman, S.L.; Devlin, R.B.; Koren, H.S.

    1991-01-01

    The study investigated changes in human alveolar macrophage (HAM) function after exposure in vitro to ozone (O3)(0.1-1.0 ppm for 2-4 hr). The functions studied reflect concern that O3 is detrimental to host defense mechanisms in the bronchoalveolar spaces. Exposure of HAM to O3 caused a concentration-dependent increase in release of prostaglandin E2(PGE2), an important modulator of inflammation, phagocytosis, and oxidative burst. Although phagocytosis of particulate immune complexes was decreased by O3, the authors found no change in the quantity of Fc receptors and complement receptors on the HAM surface. Superoxide (O2) production in response to phorbol ester was reduced after exposure of HAM to O3 while the basal O2 release in response to plastic adherence was not affected. Growth inhibition of the opportunistic yeast Cryptococcus neoformans by HAM was not affected by O3 exposure. The production of inflammatory mediators and immune modulators such as tumor necrosis factor-alpha, interleukin 1, and interleukin 6 were not induced by exposure to O3. However, compared to controls, O3-exposed HAM produced significantly lower levels of these cytokines when simulated with bacterial lipopolysaccharide (LPS).

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

    Science.gov (United States)

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

    2011-04-01

    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.

  17. In vitro ozone exposure increases release of arachidonic acid products from a human bronchial epithelial cell line

    Energy Technology Data Exchange (ETDEWEB)

    McKinnon, K.P.; Madden, M.C.; Noah, T.L.; Devlin, R.B. (TRC Environmental Corporation, Chapel Hill, NC (United States))

    1993-02-01

    Eicosanoids released after ozone exposure of a human bronchial epithelial cell line, BEAS-S6, were analyzed by high-pressure liquid chromatography (HPLC) of supernatants from exposed cells prelabeled with [3H]arachidonic acid. BEAS cells released thromboxane B2 (TxB2), prostaglandin E2 (PGE2), leukotriene C4 (LTC4), LTD4, LTE4, and 12-hydroxyheptadecatrienoic acid (HHT) after exposure to ozone at concentrations of 0.1, 0.25, 0.5, and 1.0 ppm. The eicosanoids were identified by coelution with authentic standards. The largest product from ozone-exposed BEAS cells was the most polar peak, designated Peak 1. Release of cyclooxygenase products such as TxB2, PGE2, and HHT was inhibited by acetylsalicylic acid. Peaks that migrated with authentic standards for LTB4, LTC4, and LTD4 were inhibited by the lipoxygenase inhibitor nordihydroguaiaretic acid. The leukotrienes LTB4 and LTC4/D4 could also be detected by immunoassay of concentrated peak fractions. Thus BEAS cells released eicosanoids from cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism following exposure to ozone. Airway epithelial cells may be an important source of eicosanoids following ozone stimulation in humans.

  18. Pulmonary Inflammatory Responses to Acute Meteorite Dust Exposures - to Acute Meteorite Dust Exposures - Exploration

    Science.gov (United States)

    Harrington, A. D.; McCubbin, F. M.; Kaur, J.; Smirnov, A.; Galdanes, K.; Schoonen, M. A. A.; Chen, L. C.; Tsirka, S. E.; Gordon, T.

    2017-01-01

    New initiatives to begin lunar and martian colonization within the next few decades are illustrative of the resurgence of interest in space travel. One of NASA's major concerns with extended human space exploration is the inadvertent and repeated exposure to unknown dust. This highly interdisciplinary study evaluates both the geochemical reactivity (e.g. iron solubility and acellular reactive oxygen species (ROS) generation) and the relative toxicity (e.g. in vitro and in vivo pulmonary inflammation) of six meteorite samples representing either basalt or regolith breccia on the surface of the Moon, Mars, and Asteroid 4Vesta. Terrestrial mid-ocean ridge basalt (MORB) is also used for comparison. The MORB demonstrated higher geochemical reactivity than most of the meteorite samples but caused the lowest acute pulmonary inflammation (API). Notably, the two martian meteorites generated some of the highest API but only the basaltic sample is significantly reactive geochemically. Furthermore, while there is a correlation between a meteorite's soluble iron content and its ability to generate acellular ROS, there is no direct correlation between a particle's ability to generate ROS acellularly and its ability to generate API. However, assorted in vivo API markers did demonstrate strong positive correlations with increasing bulk Fenton metal content. In summary, this comprehensive dataset allows for not only the toxicological evaluation of astromaterials but also clarifies important correlations between geochemistry and health.

  19. Major ozonated autohemotherapy promotes the recovery of upper limb motor function in patients with acute cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Xiaona Wu; Zhensheng Li; Xiaoyan Liu; Haiyan Peng; Yongjun Huang; Gaoquan Luo; Kairun Peng

    2013-01-01

    Major ozonated autohemotherapy is classically used in treating ischemic disorder of the lower limbs. In the present study, we performed major ozonated autohemotherapy treatment in patients with acute cerebral infarction, and assessed outcomes according to the U.S. National Institutes of Health Stroke Score, Modified Rankin Scale, and transcranial magnetic stimulation motor-evoked potential. Compared with the control group, the clinical total effective rate and the cortical potential rise rate of the upper limbs were significantly higher, the central motor conduction time of upper limb was significantly shorter, and the upper limb motor-evoked potential amplitude was significantly increased, in the ozone group. In the ozone group, the National Institutes of Health Stroke Score was positively correlated with the central motor conduction time and the motor-evoked potential amplitude of the upper limb. Central motor conduction time and motor-evoked potential amplitude of the upper limb may be effective indicators of motor-evoked potentials to assess upper limb motor function in cerebral infarct patients. Furthermore, major ozonated autohemotherapy may promote motor function recovery of the upper limb in patients with acute cerebral infarction.

  20. Early suppression of NFkappaB and IL-8 in bronchial epithelium after ozone exposure in healthy human subjects.

    Science.gov (United States)

    Bosson, Jenny; Blomberg, Anders; Pourazar, Jamshid; Mudway, Ian S; Frew, Anthony J; Kelly, Frank J; Sandström, Thomas

    2009-09-01

    Exposure to elevated concentrations of ozone, a common air pollutant, has been associated with numerous adverse health effects. We have previously reported the time-course of ozone-induced airway inflammation, demonstrating an early up-regulation of vascular endothelial adhesion molecules in bronchial mucosa at 1.5 hours, followed by a neutrophilic infiltration 6 hours after exposure to 0.2 ppm ozone. We hypothesized that the neutrophilic infiltration in the bronchial mucosa would reflect an early increase in bronchial epithelial expression of redox-sensitive transcription factors and kinases regulating neutrophil chemoattractant expression. To test this hypothesis, endobronchial biopsies were obtained from healthy human subjects (n = 11) 1.5 hours after 0.2 ppm of ozone and filtered air exposures (lasting for 2 hours) and stained for mitogen-activated protein kinases (MAPKs), transcription factors, and neutrophil chemoattractants. Total epithelial staining was quantified, as well as the extent of nuclear translocation. Contrary to expectation, ozone significantly suppressed total and nuclear expression of nuclear factor kappaB (NFkappaB) in bronchial epithelial cells (p = 0.02 and p = 0.003 respectively). Similarly, the total staining for phosphorylated C-jun was suppressed (p = 0.021). Expression of interleukin 8 (IL-8) in the bronchial epithelium was likewise decreased after ozone (p = 0.018), while GRO-alpha, ENA-78, C-fos, p-p38, p-JNK, and p-ERK stainings were unchanged. These data suggest that the redox-sensitive NFkappaB and activator protein 1 (AP-1) pathways within the human bronchial epithelium do not seem to be involved in the early inflammatory cell recruitment pathways in healthy subjects exposed to ozone.

  1. Co-exposure to ultrafine particulate matter and ozone causes electrocardiogram changes indicative of increased arrhythmia risk in mice

    Science.gov (United States)

    Numerous studies have shown a relationship between acute air pollution exposure and increased risk for cardiovascular morbidity and mortality. Due to the inherent complexity of air pollution, recent studies have focused on co-exposures to better understand potential interactions....

  2. Pre-exposure to ozone predisposes oak leaves to attacks by Diplodia corticola and Biscogniauxia mediterranea.

    Science.gov (United States)

    Paoletti, Elena; Anselmi, Naldo; Franceschini, Antonio

    2007-01-01

    One-year-old cork oak (Quercus suber) and turkey oak (Q. cerris) seedlings were exposed to ozone (110 ppb, 5 h day(-1), for 30 days) and were inoculated with Diplodia corticola and Biscogniauxia mediterranea, respectively, by spraying a suspension of spores on the leaves. Both fungi are endophytic and may act as weak parasites, contributing to oak decline. Ozone exposure stimulated leaf attacks after inoculation, although the physiological, visible, and structural responses of both oaks to O3 exposure were weak. In fact, steady-state gas exchange, leaf waxes, and wettability were not significantly affected by O3. In Q. cerris, O3 altered the structure of stomata, as observed by scanning microscopy, and reduced the leaf relative water content. No hyphal entry through stomata or growth towards stomata was, however, observed. Inoculations were performed in a humid chamber at low light; stomata were likely to be closed. When Q. cerris was inoculated in natural conditions, i.e., in a forest infected by B. mediterranea, seedlings pre-exposed to the enhanced O3 regime had a higher number of B. mediterranea isolates than the controls. This suggests that pre-exposure to O3 predisposed Q. cerris leaves to attacks by B. mediterranea independent of stomata. The hyphae of both fungi were able to enter the leaf through the cuticle, either by gradual in-growth into the cuticle or erosion of a hollow in the cuticle at the point of contact. The primary cause of increased leaf injury in O3-exposed seedlings appeared to be higher germination of spores than on control leaves.

  3. Pre-Exposure to Ozone Predisposes Oak Leaves to Attacks by Diplodia corticola and Biscogniauxia mediterranea

    Directory of Open Access Journals (Sweden)

    Elena Paoletti

    2007-01-01

    Full Text Available One-year-old cork oak (Quercus suber and turkey oak (Q. cerris seedlings were exposed to ozone (110 ppb, 5 h day˗1, for 30 days and were inoculated with Diplodia corticola and Biscogniauxia mediterranea, respectively, by spraying a suspension of spores on the leaves. Both fungi are endophytic and may act as weak parasites, contributing to oak decline. Ozone exposure stimulated leaf attacks after inoculation, although the physiological, visible, and structural responses of both oaks to O3 exposure were weak. In fact, steady-state gas exchange, leaf waxes, and wettability were not significantly affected by O3. In Q. cerris, O3 altered the structure of stomata, as observed by scanning microscopy, and reduced the leaf relative water content. No hyphal entry through stomata or growth towards stomata was, however, observed. Inoculations were performed in a humid chamber at low light; stomata were likely to be closed. When Q. cerris was inoculated in natural conditions, i.e., in a forest infected by B. mediterranea, seedlings pre-exposed to the enhanced O3 regime had a higher number of B. mediterranea isolates than the controls. This suggests that pre-exposure to O3 predisposed Q. cerris leaves to attacks by B. mediterranea independent of stomata. The hyphae of both fungi were able to enter the leaf through the cuticle, either by gradual in-growth into the cuticle or erosion of a hollow in the cuticle at the point of contact. The primary cause of increased leaf injury in O3-exposed seedlings appeared to be higher germination of spores than on control leaves.

  4. Modulation of human alveolar macrophage properties by ozone exposure in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Becker, S.; Madden, M.C.; Newman, S.L.; Devlin, R.B.; Koren, H.S. (ABB Environmental Services, Inc., Chapel Hill, NC (United States))

    1991-09-15

    The authors have investigated changes in human alveolar macrophage (HAM) function after exposure in vitro to ozone (O3). The functions studied reflect concern that O3 is detrimental to host defense mechanisms in the bronchoalveolar spaces. Exposure of HAM to O3 caused a concentration-dependent increase in release of prostaglandin E2 (PGE2), an important modulator of inflammation, phagocytosis, and oxidative burst. Although phagocytosis of particulate immune complexes was decreased by O3, we found no change in the quantity of Fc receptors and complement receptors on the HAM surface. Superoxide (O2-) production in response to phorbol ester was reduced after exposure of HAM to O3 while the basal O2- release in response to plastic adherence was not affected. Growth inhibition of the opportunistic yeast Cryptococcus neoformans by HAM was not affected by O3 exposure. The production of inflammatory mediators and immune modulators such as tumor necrosis factor-alpha, interleukin 1, and interleukin 6 were not induced by exposure to O3. However, compared to controls, O3- exposed HAM produced significantly lower levels of these cytokines when stimulated with bacterial lipopolysaccharide (LPS). Two-dimensional gel electrophoretic analysis of proteins made by HAM following in vitro exposure to O3 identified 11 proteins whose rate of synthesis was significantly altered. Thus, these studies show that exposure to O3 alters the functional competence of HAM. While there is a minimal effect on protein expression or synthesis, the responses of HAM to particulate immune complexes, to bacterial LPS, and to PMA are impaired. The release of arachidonic acid and PGE2 suggest that the effect of O3 is primarily targeted to the HAM cell membrane. These changes may ultimately result in increased susceptibility to inhaled infectious agents in the O3-exposed individual.

  5. Effects of ozone exposure on lipid metabolism in human alveolar macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, M.; Madden, M.C.; Samet, J.M. (Univ. of North Carolina, Chapel Hill, NC (United States)); Koren, H.S. (Environmental Protection Agency, Research Triangle Park, NC (United States))

    1992-07-01

    Alveolar macrophages (AM) store arachidonic acid (AA), which is esterified in cellular phospholipids until liberated by phospholipase A[sub C] or C after exposure to inflammatory stimuli. After release, there can be subsequent metabolism of AA into various potent, biologically active mediators including prostaglandins and platelet-activating factor (PAF). To examine the possibility that these mediators may account for some of the pathophysiologic alterations seen in the lung after ozone (O[sub 3]) exposure, human AM were collected by bronchoalveolar lavage of normal subjects, plated into tissue culture dishes, and the adherent cells were incubated with [[sup 3]H]AA or [[sup 3]H]lysoPAF. Human AM exposed to 1.0 ppm O[sub 3] for 2 hr released 65 [+-] 12% more tritium, derived from [[sup 3]H]AA, than paired, air-exposed controls into media supernatants. In other studies using a similar O[sub 3] exposure protocol, there was also a significant increase in human AM prostaglandin E[sub 2] production (2.0 [+-] 0.5-fold increase above air-exposure values, p < 0.02, n = 5). These potent lipid mediators, originally derived from human AM, may play an important role in the mechanisms of O[sub 3] lung toxicity. 25 refs., 2 figs., 5 tabs.

  6. EFFECTS OF ACUTE PYRETHROID EXPOSURE ON THERMOREGULATION IN RATS.

    Science.gov (United States)

    Pyrethroid insecticides produce acute neurotoxicity in mammals. According to the FQPA mandate, the USEPA is required to consider the risk of cumulative toxicity posed to humans through exposure to pyrethroid mixtures. Thermoregulatory response (TR) is being used to determine if t...

  7. Occupational exposure to solvents and acute myeloid leukemia

    DEFF Research Database (Denmark)

    Talibov, Madar; Lehtinen-Jacks, Susanna; Martinsen, Jan Ivar;

    2014-01-01

    OBJECTIVE: The aim of the current study was to assess the relation between occupational exposure to solvents and the risk of acute myeloid leukemia (AML). METHODS: Altogether, this study comprises 15 332 incident cases of AML diagnosed in Finland, Norway, Sweden and Iceland from 1961-2005 and 76...

  8. Human solvent exposure. Factors influencing the pharmacokinetics and acute toxicity

    DEFF Research Database (Denmark)

    Bælum, Jesper

    1991-01-01

    exposed to mixtures of solvents experience an increased frequency of work related irritative and neurological symptoms although the exposure has been far below the occupational exposure limits. A series of controlled human exposure studies was carried out. Different groups of persons were exposed...... to the most frequent solvent, toluene. Toluene in alveolar air and the urinary excretion of the metabolites were measured and the acute effects of toluene were assessed by the performance in a series of test of the perceptual and psychomotor functions as well as a standardized registration of annoyance...

  9. Health Impacts from Acute Radiation Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Strom, Daniel J.

    2003-09-30

    Absorbed doses above1-2 Gy (100-200 rads) received over a period of a day or less lead to one or another of the acute radiation syndromes. These are the hematopoietic syndrome, the gastrointestinal (GI) syndrome, the cerebrovascular (CV) syndrome, the pulmonary syndrome, or the cutaneous syndrome. The dose that will kill about 50% of the exposed people within 60 days with minimal medical care, LD50-60, is around 4.5 Gy (450 rads) of low-LET radiation measured free in air. The GI syndrome may not be fatal with supportive medical care and growth factors below about 10 Gy (1000 rads), but above this is likely to be fatal. Pulmonary and cutaneous syndromes may or may not be fatal, depending on many factors. The CV syndrome is invariably fatal. Lower acute doses, or protracted doses delivered over days or weeks, may lead to many other health outcomes than death. These include loss of pregnancy, cataract, impaired fertility or temporary or permanent sterility, hair loss, skin ulceration, local tissue necrosis, developmental abnormalities including mental and growth retardation in persons irradiated as children or fetuses, radiation dermatitis, and other symptoms listed in Table 2 on page 12. Children of parents irradiated prior to conception may experience heritable ill-health, that is, genetic changes from their parents. These effects are less strongly expressed than previously thought. Populations irradiated to high doses at high dose rates have increased risk of cancer incidence and mortality, taken as about 10-20% incidence and perhaps 5-10% mortality per sievert of effective dose of any radiation or per gray of whole-body absorbed dose low-LET radiation. Cancer risks for non-uniform irradiation will be less.

  10. No consistent effects of ozone exposure for one growth season on levels of polyamines in Picea abies

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, J.E.; Jensen, E. [Tromsoe Univ. (Norway). Dept. of Plant Physiology and Microbiology

    1998-07-01

    It is well known that ozone is detrimental to plants, due to its action as a strong oxidant. Polyamines have been suggested as protecting against oxidative stress, and have been reported as being induced by ozone in plants. However, there is a paucity of data on tree species exposed to ozone for an extended period under field-like conditions. In the present investigation, mature spruce clones were exposed to ozone (200 or 400 {mu}g m{sup -3} air) in open-top chambers for an entire growth season at two localities in Norway, and levels of the polyamines putrescine, spermidine and spermine were measured. No consistent effects of ozone fumigation were found on levels of any of the polyamines; not for two clones showing visible injury (yellow needles), and not for four apparently healthy clones. Thus, there was no correlation between sensitivity or tolerance to ozone and polyamine content. However, there were significant differences in polyamine contents between clones and the two localities of exposure 18 refs, 3 figs

  11. Reduced exercise time in competitive simulations consequent to low level ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Schelegle, E.S.; Adams, W.C.

    1986-08-01

    Ten highly trained endurance athletes were studied to determine the effects of exposure to low ozone (O/sub 3/) concentrations on simulated competitive endurance performance and associated physiological and subjective symptom responses. Each subject was randomly exposed to filtered air (FA), and to 0.12, 0.18, and 0.24 ppm O/sub 3/ while performing a 1 h competitive simulation protocol on a bicycle ergometer. Endurance performance was evaluated by the number of subjects unable to complete rides (last 30 min at an intense work load of approximately 86% VO/sub 2/max). All subjects completed the FA exposure, whereas one, five, and seven subjects did not complete the 0.12, 0.18, and 0.24 ppm O/sub 3/ exposures, respectively. Statistical analysis indicated a significant (P less than 0.05) increase in the inability of subjects to complete the competitive simulations with increasing O/sub 3/ concentration, including a significant difference between the 0.24 ppm O/sub 3/ and FA exposure. Significant decreases (P less than 0.05) were also observed following the 0.18 and 0.24 ppm O/sub 3/ exposures, respectively, in forced vital capacity (-7.8 and -9.9%), and forced expiratory volume in 1 s (-5.8 and -10.5%). No significant O/sub 3/ effect was observed for exercise respiratory metabolism or ventilatory pattern responses. However, the number of reported subjective symptoms increased significantly following the 0.18 and 0.24 ppm O/sub 3/ protocols. These data demonstrate significant decrements in simulated competitive endurance performance and in pulmonary function, with accompanying enhanced subjective symptoms, following exposure to low O/sub 3/ levels commonly observed in numerous metropolitan environments during the summer months.

  12. Ozone and cardiovascular injury

    Directory of Open Access Journals (Sweden)

    Rainaldi Giuseppe

    2009-06-01

    Full Text Available Abstract Air pollution is increasingly recognized as an important and modifiable determinant of cardiovascular diseases in urban communities. The potential detrimental effects are both acute and chronic having a strong impact on morbidity and mortality. The acute exposure to pollutants has been linked to adverse cardiovascular events such as myocardial infarction, heart failure and life-threatening arrhythmias. The long-terms effects are related to the lifetime risk of death from cardiac causes. The WHO estimates that air pollution is responsible for 3 million premature deaths each year. The evidence supporting these data is very strong nonetheless, epidemiologic and observational data have the main limitation of imprecise measurements. Moreover, the lack of clinical experimental models makes it difficult to demonstrate the individual risk. The other limitation is related to the lack of a clear mechanism explaining the effects of pollution on cardiovascular mortality. In the present review we will explore the epidemiological, clinical and experimental evidence of the effects of ozone on cardiovascular diseases. The pathophysiologic consequences of air pollutant exposures have been extensively investigated in pulmonary systems, and it is clear that some of the major components of air pollution (e.g. ozone and particulate matter can initiate and exacerbate lung disease in humans 1. It is possible that pulmonary oxidant stress mediated by particulate matter and/or ozone (O3 exposure can result in downstream perturbations in the cardiovasculature, as the pulmonary and cardiovascular systems are intricately associated, and it is well documented that specific environmental toxins (such as tobacco smoke 2 introduced through the lungs can initiate and/or accelerate cardiovascular disease development. Indeed, several epidemiologic studies have proved that there is an association between PM and O3 and the increased incidence of cardiovascular morbidity

  13. Ozone exposure- and flux-based response relationships with photosynthesis, leaf morphology and biomass in two poplar clones.

    Science.gov (United States)

    Shang, Bo; Feng, Zhaozhong; Li, Pin; Yuan, Xiangyang; Xu, Yansen; Calatayud, Vicent

    2017-12-15

    Poplar clones 546 (P. deltoides cv. '55/56'×P. deltoides cv. 'Imperial') and 107 (P. euramericana cv. '74/76') were exposed to five ozone concentrations in 15 open-top chambers (OTCs). Both ozone exposure (AOT40, Accumulation Over a Threshold hourly ozone concentration of 40ppb) and flux-based (POD7, Phytotoxic Ozone Dose above an hourly flux threshold of 7nmol O3 m(-2) PLA (projected leaf area) s(-1)) response relationships were established with photosynthesis, leaf morphology and biomass variables. Increases in both metrics showed significant negative relationships with light-saturated photosynthesis rate, chlorophyll content, leaf mass per area, actual photochemical efficiency of PSII in the light and root biomass but not with stomatal conductance (gs), leaf and stem biomass. Ozone had a greater impact on belowground than on aboveground biomass. The ranking of these indicators from higher to lower sensitivity to ozone was: photosynthetic parameters, morphological index, and biomass. Clone 546 had a higher sensitivity to ozone than clone 107. The coefficients of determination (R(2)) were similar between exposure- and flux-based dose-response relationships for each variable. The critical levels (CLs) for a 5% reduction in total biomass for the two poplar clones were 14.8ppmh for AOT40 and 9.8mmol O3 m(-2) PLA for POD7. In comparison, equivalent reduction occurred at much lower values in photosynthetic parameters (4ppmh for AOT40 and 3mmol O3 m(-2) PLA for POD7) and LMA (5.8ppmh for AOT40 and 4mmol O3 m(-2) PLA for POD7). While in recent decades different CLs have been proposed for several plant receptors especially in Europe, studies focusing on both flux-based dose-response relationships and CLs are still scarce in Asia. This study is therefore valuable for regional O3 risk assessment in Asia. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. 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.

  15. Global crop yield reductions due to surface ozone exposure: 1. Year 2000 crop production losses and economic damage

    Science.gov (United States)

    Avnery, Shiri; Mauzerall, Denise L.; Liu, Junfeng; Horowitz, Larry W.

    2011-04-01

    Exposure to elevated concentrations of surface ozone (O 3) causes substantial reductions in the agricultural yields of many crops. As emissions of O 3 precursors rise in many parts of the world over the next few decades, yield reductions from O 3 exposure appear likely to increase the challenges of feeding a global population projected to grow from 6 to 9 billion between 2000 and 2050. This study estimates year 2000 global yield reductions of three key staple crops (soybean, maize, and wheat) due to surface ozone exposure using hourly O 3 concentrations simulated by the Model for Ozone and Related Chemical Tracers version 2.4 (MOZART-2). We calculate crop losses according to two metrics of ozone exposure - seasonal daytime (08:00-19:59) mean O 3 (M12) and accumulated O 3 above a threshold of 40 ppbv (AOT40) - and predict crop yield losses using crop-specific O 3 concentration:response functions established by field studies. Our results indicate that year 2000 O 3-induced global yield reductions ranged, depending on the metric used, from 8.5-14% for soybean, 3.9-15% for wheat, and 2.2-5.5% for maize. Global crop production losses totaled 79-121 million metric tons, worth $11-18 billion annually (USD 2000). Our calculated yield reductions agree well with previous estimates, providing further evidence that yields of major crops across the globe are already being substantially reduced by exposure to surface ozone - a risk that will grow unless O 3-precursor emissions are curbed in the future or crop cultivars are developed and utilized that are resistant to O 3.

  16. Effect of chlorination and ozone pre-oxidation on the photobacteria acute toxicity for dissolved organic matter from sewage treatment plants

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The effect of chlorination and ozone pre-oxidation on the photobacteria acute toxicity for dissolved organic matter(DOM) from sewage treatment plants was investigated in this study.The results show that ozone pre-oxidation enhanced the photobacteria acute toxicity of the water samples.DOM before and after ozone pre-oxidation was fractionated by resins into six kinds of hydrophobic and hydrophilic organics.The six fractions were chlorinated individually and the photobacteria acute toxicity before and after chlorination was tested.It was found that the percentage of hydrophilic organics in DOM significantly increased after ozone pre-oxidation and hydrophilic organics exhibited remarkably higher acute toxicity than hydrophobic organics.In view of potentiometric titration and fourier transform infrared(FTIR) analysis,the hydrophilic organics showed a rather higher content of ph-OH structures than hydrophobic organics.

  17. Acute inhalation exposure of azodicarbonamide in the guinea pig.

    Science.gov (United States)

    Shopp, G M; Cheng, Y S; Gillett, N A; Bechtold, W E; Medinsky, M A; Hobbs, C H; Birnbaum, L S; Mauderly, J L

    1987-02-01

    Humans have been exposed to azodicarbonamide (ADA) by inhalation where bulk quantities of ADA are handled in the workplace. Responses of some workers have led to concern for the potential irritant and sensitizing properties of inhaled ADA. This study examined the effects of inhaling ADA on lung structure and function of guinea pigs during and after an acute exposure. Groups of 20 guinea pigs were exposed to each of 3 concentrations of ADA (19, 58, and 97 mg/m3), plus air as a control, for 1 hr. Pulmonary function was measured before exposure (baseline), during exposure, immediately after exposure and 24 hr after exposure. Dynamic compliance (Cdyn), total pulmonary resistance (RL), tidal volume (VT), respiratory frequency and minute volume were measured. In addition, gross necropsies and histological examinations of respiratory tract tissues were done either immediately following the exposure or 24 hr after exposure. There were no effects of ADA exposure on gross necropsy, histology, Cdyn, or RL. Some significant, concentration-related decreases in VT, respiratory frequency and minute volume were seen. The magnitudes of these changes were small: the largest change was seen in minute volume, amounting to a 24% decrease in the high concentration group. Inhalation exposure of guinea pigs to ADA at concentrations of up to 97 mg/m3 resulted in minor changes in pulmonary function without any changes in lung histology.

  18. Chronic exposure to ozone and nitric acid vapor results in increased levels of rat pulmonary putrescine

    Energy Technology Data Exchange (ETDEWEB)

    Sindhu, R.K.; Kikkawa, Yutaka [Department of Pathology, College of Medicine, University of California at Irvine, Irvine (United States); Mautz, W.J. [Department of Community and Environmental Medicine, University of California at Irvine, Irvine, CA (United States)

    1998-06-01

    In the past decade, there has been growing public concern for the human health effects of exposure to environmental pollutants. Ozone (O{sub 3}) is one of the most reactive components of photochemical air pollution. Despite extensive investigations by many laboratories on the functional, biochemical, and cellular effects of O{sub 3} exposure in humans, animals, and in vitro systems, questions remain concerning the potential adverse effects to human health represented by chronic near-ambient exposure to this environmental pollutant. In the present investigation, the influence of inhalation of O{sub 3} and nitric acid (HNO{sub 3}) vapor on polyamine levels was examined in rat lungs. Male F344/N rats were exposed nose-only to 0.15 ppm O{sub 3} and 50 {mu}g/m{sup 3} HNO{sub 3} vapor alone and in combination for 4 hours/day, 3 days/week for a total of 40 weeks. At this time the animals were sacrificed and their lungs were examined for polyamine contents. Exposure to O{sub 3} and O{sub 3} plus HNO{sub 3} vapor caused a significant increase in the putrescine content of the lung compared to the air-exposed controls (P < 0.05). The concentrations of pulmonary spermidine and spermine were not significantly increased by exposure to either O{sub 3} or HNO{sub 3} vapor alone or in combination compared to the air-exposed controls. The role of polyamines in repair and anti-inflammatory processes has been discussed. (orig.) (orig.) With 1 fig., 1 tab., 30 refs.

  19. 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...

  20. Ozonized autohemotherapy, a new method to treat dairy cow acute interdigital phlegmon. Comparison with ceftiofur and oxytetracycline

    Directory of Open Access Journals (Sweden)

    Bruno Pogliacani

    2010-01-01

    Full Text Available To determine whether ozone (a powerful germicidal agent administered by autohemotherapy would be useful for treat-  ment of acute interdigital phlegmon (foot rot in dairy cows, 60 animals affected by clinical signs of foot rot were used  in this trial. Twenty dairy cows were assigned to one of the three treatment groups: ceftiour sodium 1.0 mg/kg Body  Weight (B.W. i.v. every 12 h; oxytetracycline 6.0 mg/kg B.W. i.v. every 24 h; ozone 60 mg in 1000 ml of blood by i.v.  autohemotherapy every 24 h. Treatments stopped when animals were no longer lame. All the lameness stopped after  three days of ceftiour treatment, three days of oxytetracycline treatment and one day of ozone autohemotherapy treat-  ment. Use of ozone in autohemotherapy for dairy cow foot rot was as effective as ceftiour and oxytetracycline treatments,  and resulted to be the best one because milk and meat obtained from dairy cows treated with ozone were not subject to  withdrawal time. 

  1. [Experimental substantiation of use of sodium hypochlorite and ozone at a formation of intestinal anastomosis in conditions of acute intestinal obstruction and peritonitis].

    Science.gov (United States)

    Lelianov, A D; Ivliev, N V; Bazhenov, S M; Nesterov, A A

    2009-01-01

    Presented are the results of experimental research on 144 animals (the rats Wistar), on whom was carried out resection of a part of large intestine and a intestinal anastamosis was formed in the presents of acute intestinal obstruction and peritonitis. The sanitation of abdominal cavity in the basic group of animals (74) was performed using sodium hypochlorite solution and dissolved ozone. The intestinal lavage was carried out by dissolved ozone with the subsequent introduction of ozonized oil Ozonide in the area of intestinal anastamosis. The combined application of ozone and sodium produces an expressed samative effect which leads to healing of intestinal anastamosis and decreases unstability of intestinal sutures and mortality.

  2. Human physiological responses to cold exposure: Acute responses and acclimatization to prolonged exposure.

    Science.gov (United States)

    Castellani, John W; Young, Andrew J

    2016-04-01

    Cold exposure in humans causes specific acute and chronic physiological responses. This paper will review both the acute and long-term physiological responses and external factors that impact these physiological responses. Acute physiological responses to cold exposure include cutaneous vasoconstriction and shivering thermogenesis which, respectively, decrease heat loss and increase metabolic heat production. Vasoconstriction is elicited through reflex and local cooling. In combination, vasoconstriction and shivering operate to maintain thermal balance when the body is losing heat. Factors (anthropometry, sex, race, fitness, thermoregulatory fatigue) that influence the acute physiological responses to cold exposure are also reviewed. The physiological responses to chronic cold exposure, also known as cold acclimation/acclimatization, are also presented. Three primary patterns of cold acclimatization have been observed, a) habituation, b) metabolic adjustment, and c) insulative adjustment. Habituation is characterized by physiological adjustments in which the response is attenuated compared to an unacclimatized state. Metabolic acclimatization is characterized by an increased thermogenesis, whereas insulative acclimatization is characterized by enhancing the mechanisms that conserve body heat. The pattern of acclimatization is dependent on changes in skin and core temperature and the exposure duration.

  3. Effect of ozone exposure on lung functions and plasma prostaglandin and thromboxane concentrations in guinea pigs

    Energy Technology Data Exchange (ETDEWEB)

    Miller, P.D.; Ainsworth, D.; Lam, H.F.; Amdur, M.O.

    1987-03-30

    Male Hartley guinea pigs were exposed either to filtered air or to 1 ppm ozone (O/sub 3/) for 1 hr. At 2, 8, 24, or 48 hr after exposure we measured ventilation, respiratory mechanics, lung volumes, diffusing capacity for carbon monoxide (DLCO), and alveolar volume (VA) in anesthetized, tracheotomized animals. Respiratory frequency and tidal volume were unchanged in all groups. Pulmonary resistance was increased 2 hr after O/sub 3/ but returned to control at 8 hr and thereafter. Prolonged reductions in lung volumes (total lung capacity, vital capacity, functional residual capacity, and residual volume) as well as in DLCO and VA occurred after O/sub 3/, with maximum decreases at 8 and 24 hr postexposure. Increased ratios of wet lung weight to body weight were seen at 2, 8, and 24 hr. In separate groups of animals, also exposed either to filtered air or to 1 ppm O/sub 3/, plasma eicosanoid (EC) concentrations were measured at 2, 8, 24, 48, or 72 hr after exposure. Significant increases in thromboxane B2 concentrations were seen at 2, 24, and 48 hr after exposure. Plasma concentrations of 6-keto prostaglandin F1 alpha (PGF1 alpha) and prostaglandin E1 (PGE1) were increased at 24 hr and at 24, 48, and 72 hr, respectively. The nature of this long-term pulmonary response to a short-term exposure to O/sub 3/ suggests alveolar involvement, including probable alveolar duct constriction and localized pulmonary edema. Although changes in plasma EC concentrations were observed concurrent with impaired lung functions, no simple causal relationship was apparent from these studies.

  4. Soil Water Availability Modulation Over Estimated Relative Yield Losses in Wheat (Triticum aestivum L. Due to Ozone Exposure

    Directory of Open Access Journals (Sweden)

    Daniel De la Torre

    2007-01-01

    Full Text Available The approach developed by Fuhrer in 1995 to estimate wheat yield losses induced by ozone and modulated by the soil water content (SWC was applied to the data on Catalonian wheat yields. The aim of our work was to apply this approach and adjust it to Mediterranean environmental conditions by means of the necessary corrections. The main objective pursued was to prove the importance of soil water availability in the estimation of relative wheat yield losses as a factor that modifies the effects of tropospheric ozone on wheat, and to develop the algorithms required for the estimation of relative yield losses, adapted to the Mediterranean environmental conditions. The results show that this is an easy way to estimate relative yield losses just using meteorological data, without using ozone fluxes, which are much more difficult to calculate. Soil water availability is very important as a modulating factor of the effects of ozone on wheat; when soil water availability decreases, almost twice the amount of accumulated exposure to ozone is required to induce the same percentage of yield loss as in years when soil water availability is high.

  5. Acute liver failure associated with occupational exposure to tetrachloroethylene.

    Science.gov (United States)

    Shen, Chuan; Zhao, Cai-Yan; Liu, Fang; Wang, Ya-Dong; Wang, Wei

    2011-01-01

    Tetrachloroethylene is a chlorinated solvent that is primarily used in dry cleaning and degreasing operations. Although the hepatotoxicity caused by tetrachloroethylene has been well documented in literature, it is rarely considered as a cause of acute liver failure. We report a case of a 39-yr-old man who was admitted to our hospital for acute liver failure due to tetrachloroethylene exposure. Histological examination of the liver revealed massive hepatic necrosis, prominently, in zone 3 of the hepatic lobules. The patient underwent supportive treatment along with 3 sessions of plasmapheresis, and consequently, he presented a favorable outcome. Repeat liver biopsy performed 6 months after the patient's discharge showed architectural distortion with postnecrotic cirrhosis. Physicians should be aware of the possibility of acute liver failure induced by tetrachloroethylene. Early plasmapheresis can be effective for individuals with sufficient capacity for hepatocyte regeneration.

  6. 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.

  7. Alteration of extracellular enzymes in pinto bean leaves upon exposure to air pollutants, ozone and sulfur dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Peters, J.L.; Castillo, F.J.; Heath, R.L. (Univ. of California, Riverside (USA))

    1989-01-01

    Diamine oxidase and peroxidase, associated with the wall in pinto bean (Phaseolus vulgaris L. var Pinto) leaves, can be washed out by vacuum infiltration and assayed without grinding the leaf. The diamine oxidase activity is inhibited in vivo by exposure of the plants to ozone (dose of 0.6 microliters per liter {times} hour), whereas the peroxidase activity associated with the wall space is stimulated. This dose does not cause obvious necrosis or chlorosis of the leaf. These alterations are greater when the dose of ozone exposure is given as a triangular pulse (a slow rise to a peak of 0.24 microliters per liter followed by a slow fall) compared to that given as a constant square wave pulse of 0.15 microliters per liter for the same 4 hour period. Exposure of the plants to sulfur dioxide (at a concentration of 0.4 microliters per liter for 4 hours) does not result in any change in the diamine oxidase or peroxidase activities, yet the total sulfhydryl content of the leaf is increased, demonstrating the entry of sulfur dioxide. These two pollutants, with different chemical reactivities, affect the activities of the extracellular enzymes in different manners. In the case of ozone exposure, the inhibition of extracellular diamine oxidase could profoundly alter the movements of polyamines from cell to cell.

  8. Acute and recent air pollution exposure and cardiovascular events at labour and delivery

    Science.gov (United States)

    Männistö, Tuija; Mendola, Pauline; Grantz, Katherine Laughon; Leishear, Kira; Sundaram, Rajeshwari; Sherman, Seth; Ying, Qi; Liu, Danping

    2017-01-01

    Objective To study the relationship between acute air pollution exposure and cardiovascular events during labour/delivery. Methods The Consortium on Safe Labor (2002–2008), an observational US cohort with 223 502 singleton deliveries provided electronic medical records. Air pollution exposure was estimated by modified Community Multiscale Air Quality models. Cardiovascular events (cardiac failure/arrest, stroke, myocardial infarcts and other events) were recorded in the hospital discharge records for 687 pregnancies (0.3%). Logistic regression with generalised estimating equations estimated the relationship between cardiovascular events and daily air pollutant levels for delivery day and the 7 days preceding delivery. Results Increased odds of cardiovascular events were observed for each IQR increase in exposure to nitric oxides at 5 and 6 days prior to delivery (OR=1.17, 99% CI 1.04 to 1.30 and OR=1.15, 1.03 to 1.28, respectively). High exposure to toxic air pollution species such as ethylbenzene (OR=1.50, 1.08 to 2.09), m-xylene (OR=1.54, 1.11 to 2.13), o-xylene (OR=1.51, 1.09 to 2.09), p-xylene (OR=1.43, 1.03 to 1.99) and toluene (OR=1.42, 1.02 to 1.97) at 5 days prior to delivery were also associated with cardiovascular events. Decreased odds of events were observed with exposure to ozone. Conclusions Air pollution in the days prior to delivery, especially nitrogen oxides and some toxic air pollution species, was associated with increased risk of cardiovascular events during the labour/delivery admission. PMID:26105036

  9. Responses of older men with and without chronic obstructive pulmonary disease to prolonged ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Gong, H. Jr.; Shamoo, D.A.; Anderson, K.R.; Linn, W.S. [Los Amigos Research and Education Institute, Inc., Downey, CA (United States)

    1997-01-01

    We tested responses to ozone (O{sub 3}) under simulated {open_quotes}worst-case{close_quotes} ambient exposure conditions. Subjects included 9 men who had severe chronic obstructive pulmonary disease (COPD) with subnormal carbon monoxide diffusing capacity (i.e., an emphysemic component) and 10 age-matched healthy men. Each subject was exposed to 0.24 ppm O{sub 3} and to clean air (control) in an environmentally controlled chamber at 24{degrees}C and 40% relative humidity. Exposures were randomized, they occurred 1 wk apart, and they lasted 4 h. During each half-hour interval, light exercise occurred (e.e., average ventilation 20 l/mm) for 15 min. during both control and O{sub 3} exposures, group mean symptom intensity and specific airway resistance (SRaw) increased, whereas forced expiratory performance decreased. The healthy subgroup`s mean arterial oxygen saturation (SaO{sub 2}) rose slightly, and the COPD subgroup`s mean SaO{sub 2} declined slightly, during exercise. Group mean forced expiratory volume in 1 s (FEV{sub 1.0}) declined significantly in O{sub 3} exposures, compared with controls (p {approx}.01). Mean excess FEV{sub 1.0} loss after 4 h in O{sub 3} (relative to control) was 8% of the preexposure value in the COPD subgroup, compared with 3% in the healthy subgroup (p > .05 [nonsignificant]). Overall FEV{sub 1.0} loss during O{sub 3} exposures, including exercise effects, averaged 19% in the COPD subgroup, compared with 2% in the healthy subgroup (p < .001). Symptoms, SRaw, and SaO{sub 2} responses, as well as healthy subjects` postexposure bronchial reactivity, differed little between O{sub 3}-exposed and control subjects. We therefore concluded that in older men with or without severe COPD, O{sub 3} causes lung dysfunction under {open_quotes}worst-case{close_quotes} ambient exposure conditions, despite older subjects` comparative unresponsiveness to O{sub 3}. 30 refs., 2 figs., 2 tabs.

  10. Acute versus repeated chocolate exposure: effects on intake and cravings in restrained and unrestrained eaters.

    Science.gov (United States)

    Coelho, Jennifer S; Nederkoorn, Chantal; Jansen, Anita

    2014-04-01

    The cue-reactivity model, which is based on conditioning processes, posits that repeated food exposure (in the absence of consumption) should decrease cue reactivity. To examine whether repeated chocolate exposure attenuates cravings and intake, relative to those exposed to an acute cue, a 2 (repeated vs acute cue) × 2 (restrained vs unrestrained eaters) design was employed. Fifty female participants were recruited. Repeated exposure reduced cravings in unrestrained eaters (relative to acute exposure), but increased cravings in restrained eaters. An interaction between restraint and exposure emerged on intake, such that restrained eaters ate less after acute exposure than did unrestrained eaters.

  11. Ozone increases airway hyperreactivity and mucus hyperproduction in mice previously exposed to allergen

    DEFF Research Database (Denmark)

    Larsen, Søren T; Matsubara, Shigeki; McConville, Glen

    2010-01-01

    Acute exacerbations of asthma represent a common clinical problem with major economic impact. Air pollutants including ozone have been shown to contribute to asthma exacerbation, but the mechanisms underlying ozone-induced asthma exacerbation are only partially understood. The present study aimed...... exposure to clean air or 100, 250, or 500 ppb ozone. Ozone induced AHR in mice previously exposed to OVA when compared to non-exposed (saline) control mice. After a 10-d exposure to OVA, a single exposure to a low (100 ppb) ozone concentration was sufficient to induce AHR. The AHR response was associated...... with goblet-cell metaplasia. Even the lowest concentration of ozone tested, 100 ppb, which may be exceeded in urban environments and in the workplace, resulted in a significant increase in AHR, most prominent 24 h after exposure in the OVA-exposed mice....

  12. Canopy carbon budget of Siebold's beech (Fagus crenata) sapling under free air ozone exposure.

    Science.gov (United States)

    Watanabe, Makoto; Hoshika, Yasutomo; Inada, Naoki; Koike, Takayoshi

    2014-01-01

    To determine the effects of ozone (O3) on the canopy carbon budget, we investigated photosynthesis and respiration of leaves of Siebold's beech saplings under free air O3 exposure (60 nmol mol(-1), during daytime) in relation to the within-canopy light gradient; we then calculated the canopy-level photosynthetic carbon gain (PCG) and respiratory carbon loss (RCL) using a canopy photosynthesis model. Susceptibilities of photosynthesis and respiration to O3 were greater in leaves of upper canopy than in the lower canopy. The canopy net carbon gain (NCG) was reduced by O3 by 12.4% during one growing season. The increased RCL was the main factor for the O3-induced reduction in NCG in late summer, while contributions of the reduced PCG and the increased RCL to the NCG were almost the same in autumn. These results indicate contributions of changes in PCG and RCL under O3 to NCG were different between seasons.

  13. Protein Cross-Linking and Oligomerization through Dityrosine Formation upon Exposure to Ozone.

    Science.gov (United States)

    Kampf, Christopher J; Liu, Fobang; Reinmuth-Selzle, Kathrin; Berkemeier, Thomas; Meusel, Hannah; Shiraiwa, Manabu; Pöschl, Ulrich

    2015-09-15

    Air pollution is a potential driver for the increasing prevalence of allergic disease, and post-translational modification by air pollutants can enhance the allergenic potential of proteins. Here, the kinetics and mechanism of protein oligomerization upon ozone (O3) exposure were studied in coated-wall flow tube experiments at environmentally relevant O3 concentrations, relative humidities and protein phase states (amorphous solid, semisolid, and liquid). We observed the formation of protein dimers, trimers, and higher oligomers, and attribute the cross-linking to the formation of covalent intermolecular dityrosine species. The oligomerization proceeds fast on the surface of protein films. In the bulk material, reaction rates are limited by diffusion depending on phase state and humidity. From the experimental data, we derive a chemical mechanism and rate equations for a kinetic multilayer model of surface and bulk reaction enabling the prediction of oligomer formation. Increasing levels of tropospheric O3 in the Anthropocene may promote the formation of protein oligomers with enhanced allergenicity and may thus contribute to the increasing prevalence of allergies.

  14. Endocrine responses in the rhesus monkey during acute cold exposure

    Energy Technology Data Exchange (ETDEWEB)

    Lotz, W.G.; Saxton, J.L. (Naval Aerospace Medical Research Lab., Pensacola, FL (United States))

    1991-03-11

    The authors studied five young male rhesus monkeys (Macaca mulatta), 3.4 to 6.7 kg, to determine the relationship between fluid balance hormones and urine production during acute, dry cold exposure. Each monkey served as its own control in duplicate experimental sessions at 6C or 26C. A 6-h experimental session consisted of 120 min equilibration at 26C, 120 min experimental exposure, and 120 min recovery at 26C. Urinary and venous catheters were inserted on the morning of a session. Rectal (Tre) and skin temperatures were monitored continuously. Blood samples were taken at 0, 30, 60 and 120 min of exposure, and at 60 min postexposure. Plasma was analyzed for arginine vasopressin (AVP), atrial natriuretic factor (ANF), plasma renin activity (PRA), plasma aldosterone (PA), and osmolality. Urine samples were analyzed for osmolality, electrolytes, and creatinine. Mean Tre was 1.6C lower after 120 min at 6C than at 26C. Urine volume and osmolality were not altered by cold exposure, as they are in humans and rats. Vasopressin and PA increased sharply, with mean plasma levels in monkeys exposed to cold more than threefold and tenfold, respectively, the levels in monkeys exposed at 26C. In contrast, ANF, PRA, and plasma osmolality were not significantly changed by cold exposure. The absence of a cold-induced diuresis in the monkey may be related to the marked increase in plasma AVP level.

  15. Ozone exposure inside museums in the historic central district of Krakow, Poland

    Science.gov (United States)

    Salmon, Lynn G.; Cass, Glen R.; Bruckman, Katarzyna; Haber, Jerzy

    Ozone present in the indoor atmosphere of museums can lead to the fading of organic artists' pigments and textile dyes that are present in paintings, tapestries and historically important clothing exhibits. Ozone concentrations were measured in outdoor air and within the interior galleries of five institutions that house cultural properties in Krakow. The purpose of these experiments was to determine the degree of penetration of outdoor ozone into these museums, and in the case of the National Museum to determine the effectiveness of the existing ozone removal system at that site. It was found that those museums that are rapidly ventilated through many open doors and windows experienced indoor ozone concentrations about 42-44% as high as those outdoors. The Senator's Hall at Wawel Castle, which houses important tapestries, experiences indoor ozone concentrations that are 17-19% of those outdoors due to ozone removal at interior surfaces during transit through the building from distant air intake points. Methods for further reduction of ozone concentrations in the specific museums studied are discussed.

  16. 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...

  17. 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/

  18. 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

  19. Localized ozone fumigation system for studying ozone effects on photosynthesis, respiration, electron transport rate and isoprene emission in field-grown Mediterranean oak species

    Energy Technology Data Exchange (ETDEWEB)

    Velikova, V.; Tsonev, T. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. of Plant Physiology; Pinelli, P.; Alessio, G.A.; Loreto, F. [CNR Inst. de Biologia Agroambiental e Forestale, Rome (Italy)

    2005-12-01

    Although ozone typically forms in highly populated and industrialized areas of the world, its presence in rural areas indicates that it can also be formed by interactions between anthropogenic and biogenic precursors. Ozone concentrations often rise above phytotoxic thresholds, resulting in reduced plant productivity and visible damage to foliage. This study examined the effects of acute and prolonged ozone exposure on some physiological traits of Mediterranean vegetation. A localized ozone fumigation system was used on single leaves in an oak canopy that was not in an enclosed system. The main objectives were to determine if primary and secondary metabolism of Mediterranean oak are sensitive to acute and prolonged, but not chronic, super-ambient or high ozone. Another objective was to determine if leaf ontogeny plays a role in establishing ozone sensitivities in the plant canopy. The study provided evidence that Mediterranean oak are generally resistant to short-term high ozone exposure, because no permanent damage was noted during the 3-day long fumigation. Carbon assimilation of current-year leaves was temporarily affected by exposure to high ozone, but recovery was quick and may have involved increasing resistance to carbon dioxide diffusion and photochemical damage. The fact that biochemical stress markers were influenced only by high ozone concentrations indicates that biochemical changes occurred in the absence of large physiological changes, but may affect the long-term development and performance of leaves exposed to ozone stress. 40 refs., 1 tab., 6 figs.

  20. Visible leaf injury in young trees of Fagus sylvatica L. and Quercus robur L. in relation to ozone uptake and ozone exposure. An Open-Top Chambers experiment in South Alpine environmental conditions

    Energy Technology Data Exchange (ETDEWEB)

    Gerosa, G. [Catholic University of Brescia, Department of Mathematics and Physics, Via dei Musei 41, 25125 Brescia (Italy); Marzuoli, R. [Catholic University of Brescia, Department of Mathematics and Physics, Via dei Musei 41, 25125 Brescia (Italy)], E-mail: riccardo.marzuoli@unicatt.it; Desotgiu, R.; Bussotti, F. [University of Florence, Department of Plant Biology, Piazzale delle Cascine 28, 50144 Florence (Italy); Ballarin-Denti, A. [Catholic University of Brescia, Department of Mathematics and Physics, Via dei Musei 41, 25125 Brescia (Italy)

    2008-03-15

    An Open-Top Chambers experiment on Fagus sylvatica and Quercus robur seedlings was conducted in order to compare the performance of an exposure-based (AOT40) and a flux-based approaches in predicting the appearance of ozone visible injuries on leaves. Three different ozone treatments (charcoal-filtered; non-filtered; and open plots) and two soil moisture treatments (watered and non-watered plots) were performed. A Jarvisian stomatal conductance model was drawn up and parameterised for both species and typical South Alpine environmental conditions, thus allowing the calculation of ozone stomatal fluxes for every treatment. A critical ozone flux level for the onset of leaf visible injury in beech was clearly identified between 32.6 and 33.6 mmol O{sub 3}m{sup -2}. In contrast, it was not possible to identify an exposure critical level using the AOT40 index. Water stress delayed the onset of the leaf visible injuries, but the flux-based approach was able to take it into account accurately. - Ozone fluxes are more accurate than AOT40 exposure index in predicting ozone visible foliar injury onset on beech seedlings in South Alpine environmental conditions.

  1. 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 le

  2. Impact of day-time and/or night-time ozone exposure on visible injury and leaf conductance of subterranean clover, Trifolium subterraneum

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, G.P.; Danielsson, H.; Pleijel, H. [Goeteborg Univ., Goeteborg (Sweden). Inst. of Environmental Science and Conservation; Karlsson, P.E. [Swedish Environmental Reserch Inst. (IVL), Goeteborg (Sweden)

    2002-07-01

    Subterranean clover (Trifolium subterraneum) plants were exposed during two days to four different ozone treatments in Open-Top Chambers (OTC). The ozone treatments were: 1. Day CF/Night CF, 2. Day CF+/Night CF, 3. Day CF/Night CF+, 4. Day CF+/Night CF+, where CF=charcoal-filtered air (5-15 ppb); CF+=charcoal-filtered air plus extra ozone (30-60 ppb). The leaf stomatal conductance was measured on six occasions during 34 hours. After one week, the plants were harvested and the visible injury was estimated on the leaves of the main shoot of each plant. The treatments which received CF during the day showed significantly less visible injury than the treatments that received CF+during the day. Night-time ozone exposure generally did not affect the development of ozone-induced visible injury of leaves of subterranean clover, except, maybe the development of slight visible injury. It is possible that the short Nordic summer nights allow some stomatal ozone uptake during nighttime. Ozone exposure with levels around 50 ppb for two days did affect the leaf conductance of subterranean clover. The stomatal conductance was lower when the leaves were exposed to high concentrations of ozone. Maximum sensitivity of the leaves was found among the leaves of moderate age. Young leaves are less sensitive than older leaves and very old leaves (though without visible symptoms of senescence) tended to be less sensitive than moderately old leaves. (orig.)

  3. Acute radiation syndrome caused by accidental radiation exposure - therapeutic principles

    Directory of Open Access Journals (Sweden)

    Dörr Harald

    2011-11-01

    Full Text Available Abstract Fortunately radiation accidents are infrequent occurrences, but since they have the potential of large scale events like the nuclear accidents of Chernobyl and Fukushima, preparatory planning of the medical management of radiation accident victims is very important. Radiation accidents can result in different types of radiation exposure for which the diagnostic and therapeutic measures, as well as the outcomes, differ. The clinical course of acute radiation syndrome depends on the absorbed radiation dose and its distribution. Multi-organ-involvement and multi-organ-failure need be taken into account. The most vulnerable organ system to radiation exposure is the hematopoietic system. In addition to hematopoietic syndrome, radiation induced damage to the skin plays an important role in diagnostics and the treatment of radiation accident victims. The most important therapeutic principles with special reference to hematopoietic syndrome and cutaneous radiation syndrome are reviewed.

  4. Effects of asphalt fume condensate exposure on acute pulmonary responses

    Energy Technology Data Exchange (ETDEWEB)

    Ma, J.Y.C.; Barger, M.W.; Castranova, V. [Health Effects Lab. Div., National Inst. for Occupational Safety and Health, Morgantown, WV (United States); Kriech, A.J. [Heritage Research Group, Indianapolis, IN (United States)

    2000-10-01

    The present study was carried out to characterize the effects of in vitro exposure to paving asphalt fume condensate (AFC) on alveolar macrophage (AM) functions and to monitor acute pulmonary responses to in vivo AFC exposure in rats. Methods: For in vitro studies, rat primary AM cultures were incubated with various concentrations of AFC for 24 h at 37 C. AM-conditioned medium was collected and assayed for lactate dehydrogenase (LDH) as a marker of cytotoxicity. Tumor necrosis factor-{alpha} (TNF-{alpha}) and interleukin-1 (IL-1) production were assayed in AM-conditioned medium to monitor AM function. The effect of AFC on chemiluminescence (CL) generated by resting AM or AM in response to zymosan or PMA stimulation was also determined as a marker of AM activity. For in vivo studies, rats received either (1) a single intratracheal (IT) instillation of saline, or 0.1 mg or 0.5 mg AFC and were killed 1 or 3 days later; or (2) IT instillation of saline, or 0.1, 0.5, or 2 mg AFC for three consecutive days and were killed the following day. Differential counts of cells harvested by bronchoalveolar lavage were measured to monitor inflammation. Acellular LDH and protein content in the first lavage fluid were measured to monitor damage. CL generation, TNF-{alpha} and IL-1 production by AM were assayed to monitor AM function. Results: In vitro AFC exposure at <200 {mu}g/ml did not induce cytotoxicity, oxidant generation, or IL-1 production by AM, but it did cause a small but significant increase in TNF-{alpha} release from AM. In vitro exposure of AM to AFC resulted in a significant decline of CL in response to zymosan or PMA stimulation. The in vivo studies showed that AFC exposure did not induce significant neutrophil infiltration or alter LDH or protein content in acellular lavage samples. Macrophages obtained from AFC-exposed rats did not show significant differences in oxidant production or cytokine secretion at rest or in response to LPS in comparison with control

  5. Responses of Hyalella azteca to acute and chronic microplastic exposures.

    Science.gov (United States)

    Au, Sarah Y; Bruce, Terri F; Bridges, William C; Klaine, Stephen J

    2015-11-01

    Limited information is available on the presence of microplastics in freshwater systems, and even less is known about the toxicological implications of the exposure of aquatic organisms to plastic particles. The present study was conducted to evaluate the effects of microplastic ingestion on the freshwater amphipod, Hyalella azteca. Hyalella azteca was exposed to fluorescent polyethylene microplastic particles and polypropylene microplastic fibers in individual 250-mL chambers to determine 10-d mortality. In acute bioassays, polypropylene microplastic fibers were significantly more toxic than polyethylene microplastic particles; 10-d lethal concentration 50% values for polyethylene microplastic particles and polypropylene microplastic fibers were 4.64 × 10(4) microplastics/mL and 71.43 microplastics/mL, respectively. A 42-d chronic bioassay using polyethylene microplastic particles was conducted to quantify effects on reproduction, growth, and egestion. Chronic exposure to polyethylene microplastic particles significantly decreased growth and reproduction at the low and intermediate exposure concentrations. During acute exposures to polyethylene microplastic particles, the egestion times did not significantly differ from the egestion of normal food materials in the control; egestion times for polypropylene microplastic fibers were significantly slower than the egestion of food materials in the control. Amphipods exposed to polypropylene microplastic fibers also had significantly less growth. The greater toxicity of microplastic fibers than microplastic particles corresponded with longer residence times for the fibers in the gut. The difference in residence time might have affected the ability to process food, resulting in an energetic effect reflected in sublethal endpoints.

  6. Increased oxidative stress following acute and chronic high altitude exposure.

    Science.gov (United States)

    Jefferson, J Ashley; Simoni, Jan; Escudero, Elizabeth; Hurtado, Maria-Elena; Swenson, Erik R; Wesson, Donald E; Schreiner, George F; Schoene, Robert B; Johnson, Richard J; Hurtado, Abdias

    2004-01-01

    The generation of reactive oxygen species is typically associated with hyperoxia and ischemia reperfusion. Recent evidence has suggested that increased oxidative stress may occur with hypoxia. We hypothesized that oxidative stress would be increased in subjects exposed to high altitude hypoxia. We studied 28 control subjects living in Lima, Peru (sea level), at baseline and following 48 h exposure to high altitude (4300 m). To assess the effects of chronic altitude exposure, we studied 25 adult males resident in Cerro de Pasco, Peru (altitude 4300 m). We also studied 27 subjects living in Cerro de Pasco who develop excessive erythrocytosis (hematocrit > 65%) and chronic mountain sickness. Acute high altitude exposure led to increased urinary F(2)-isoprostane, 8-iso PGF(2 alpha) (1.31 +/- 0.8 microg/g creatinine versus 2.15 +/- 1.1, p = 0.001) and plasma total glutathione (1.29 +/- 0.10 micromol versus 1.37 +/- 0.09, p = 0.002), with a trend to increased plasma thiobarbituric acid reactive substance (TBARS) (59.7 +/- 36 pmol/mg protein versus 63.8 +/- 27, p = NS). High altitude residents had significantly elevated levels of urinary 8-iso PGF(2 alpha) (1.3 +/- 0.8 microg/g creatinine versus 4.1 +/- 3.4, p = 0.007), plasma TBARS (59.7 +/- 36 pmol/mg protein versus 85 +/- 28, p = 0.008), and plasma total glutathione (1.29 +/- 0.10 micromol versus 1.55 +/- 0.19, p < 0.0001) compared to sea level. High altitude residents with excessive erythrocytosis had higher levels of oxidative stress compared to high altitude residents with normal hematological adaptation. In conclusion, oxidative stress is increased following both acute exposure to high altitude without exercise and with chronic residence at high altitude.

  7. Assessment of rice yield loss due to exposure to ozone pollution in Southern Vietnam

    Energy Technology Data Exchange (ETDEWEB)

    Danh, Ngo Thanh; Huy, Lai Nguyen; Oanh, Nguyen Thi Kim, E-mail: kimoanh@ait.ac.th

    2016-10-01

    The study domain covered the Eastern region of Southern of Vietnam that includes Ho Chi Minh City (HCMC) and five other provinces. Rice production in the domain accounted for 13% of the national total with three crop cycles per year. We assessed ozone (O{sub 3}) induced rice production loss in the domain for 2010 using simulated hourly surface O{sub 3} concentrations (WRF/CAMx; 4 km resolution). Simulated O{sub 3} was higher in January–February (largely overlaps the first crop) and September–December (third crop), and lower in March–June (second crop). Spatially, O{sub 3} was higher in downwind locations of HCMC and were comparable with observed data. Relative yield loss (RYL) was assessed for each crop over the respective growing period (105 days) using three metrics: AOT40, M7 and flux-based O{sub 3} dose of POD{sub 10}. Higher RYL was estimated for the downwind of HCMC. Overall, the rice production loss due to O{sub 3} exposure in the study domain in 2010 was the highest for the first crop (up to 25,800 metric tons), the second highest for the third crop (up to 21,500 tons) and the least for the second crop (up to 6800 tons). The low RYL obtained for the second crop by POD{sub 10} may be due to the use of a high threshold value (Y = 10 nmol m{sup −2} s{sup −1}). Linear regression between non-null radiation POD{sub 0} and POD{sub 10} had similar slopes for the first and third crop when POD{sub 0} was higher and very low slope for the second crop when POD{sub 0} was low. The results of this study can be used for the rice crop planning to avoid the period of potential high RYL due to O{sub 3} exposure. - Highlights: • Simulated O{sub 3} was used to assess rice yield loss in a domain of Southern Vietnam. • Exposure metrics of AOT40, M7, POD{sub 0} and POD{sub 10} were considered. • POD{sub 10} gave the highest rice production loss. • Higher production loss was found downwind of Ho Chi Minh City.

  8. Leaf phenolic compounds in red clover (Trifolium pratense L.) induced by exposure to moderately elevated ozone

    Energy Technology Data Exchange (ETDEWEB)

    Saviranta, Niina M.M. [University of Kuopio, Department of Biosciences, Institute of Applied Biotechnology, Box 1627, 70211 Kuopio (Finland); Julkunen-Tiitto, Riitta; Oksanen, Elina [University of Joensuu, Faculty of Biosciences, Natural Product Research Laboratories, Box 111, 80101 Joensuu (Finland); Karjalainen, Reijo O., E-mail: reijo.karjalainen@uku.f [University of Kuopio, Department of Biosciences, Institute of Applied Biotechnology, Box 1627, 70211 Kuopio (Finland); AgriFood Research Finland, 31600 Jokioinen (Finland)

    2010-02-15

    Red clover (Trifolium pratense L.), an important feed crop in many parts of the world, is exposed to elevated ozone over large areas. Plants can limit ozone-induced damages by various defence mechanisms. In this work, changes in the concentrations of antioxidant phenolic compounds induced by slightly elevated levels of ozone were determined in red clover leaves by high-performance liquid chromatography and mass spectrometry. 31 different phenolics were identified and the most abundant isoflavones and flavonoids were biochanin A glycoside malonate (G-M), formononetin-G-M and quercetin-G-M. Elevated ozone (mean 32.4 ppb) increased the total phenolic content of leaves and also had minor effects on the concentrations of individual compounds. Elevated ozone increased the net photosynthesis rate of red clover leaves before visible injuries by 21-23%. This study thus suggests that the concentrations of phenolics in red clover leaves change in response to slightly elevated ozone levels. - Concentrations of antioxidant phenolic compounds from red clover can be influenced by elevated ozone.

  9. 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.

  10. Projected carbon dioxide to increase grass pollen and allergen exposure despite higher ozone levels.

    Science.gov (United States)

    Albertine, Jennifer M; Manning, William J; DaCosta, Michelle; Stinson, Kristina A; Muilenberg, Michael L; Rogers, Christine A

    2014-01-01

    One expected effect of climate change on human health is increasing allergic and asthmatic symptoms through changes in pollen biology. Allergic diseases have a large impact on human health globally, with 10-30% of the population affected by allergic rhinitis and more than 300 million affected by asthma. Pollen from grass species, which are highly allergenic and occur worldwide, elicits allergic responses in 20% of the general population and 40% of atopic individuals. Here we examine the effects of elevated levels of two greenhouse gases, carbon dioxide (CO2), a growth and reproductive stimulator of plants, and ozone (O3), a repressor, on pollen and allergen production in Timothy grass (Phleum pratense L.). We conducted a fully factorial experiment in which plants were grown at ambient and/or elevated levels of O3 and CO2, to simulate present and projected levels of both gases and their potential interactive effects. We captured and counted pollen from flowers in each treatment and assayed for concentrations of the allergen protein, Phl p 5. We found that elevated levels of CO2 increased the amount of grass pollen produced by ∼50% per flower, regardless of O3 levels. Elevated O3 significantly reduced the Phl p 5 content of the pollen but the net effect of rising pollen numbers with elevated CO2 indicate increased allergen exposure under elevated levels of both greenhouse gases. Using quantitative estimates of increased pollen production and number of flowering plants per treatment, we estimated that airborne grass pollen concentrations will increase in the future up to ∼200%. Due to the widespread existence of grasses and the particular importance of P. pratense in eliciting allergic responses, our findings provide evidence for significant impacts on human health worldwide as a result of future climate change.

  11. Effects of Acute Exposures to Carbon Dioxide upon Cognitive Functions

    Science.gov (United States)

    Ryder, V. E.; Scully, R. R.; Alexander, D. J.; Lam, C. W.; Young, M.; Satish, U.; Basner, M.

    2017-01-01

    Carbon dioxide (CO2) originates from human metabolism and typically remains about 10-fold higher in concentration on the International Space Station (ISS) than at the earth's surface. There have been recurring complaints by crew members of episodes of "mental viscosity" adversely affecting their performance, and there is evidence from the ISS that associates CO2 levels with reports of headaches by crewmembers. Consequently, flight rules have been employed to control CO2 below 3 mm Hg, which is well below the existing Spacecraft Maximum Allowable Concentration (SMAC) of 10 mm Hg for 24-hour exposures, and 5.3 mm Hg for exposures of 7 to 180 days. Headaches, while sometime debilitating themselves, are also symptoms that can provide evidence that physiological defense mechanisms have been breached, and there is evidence that CO2 has effects at levels below the threshold for headaches. This concern appears to be substantiated in reports that CO2 at concentrations below 2 mm Hg substantially reduced some cognitive functions that are associated with the ability to make complex decisions in conditions that are characterized by volatility, uncertainty, complexity, ambiguity, and delayed feedback. These are conditions that could be encountered by crews in off-nominal situations or during the first missions beyond low earth orbit. Therefore, we set out to determine if decision-making under volatile, uncertain, confusing and ambiguous circumstances, where feedback is delayed or absent, is correlated with low levels of CO2 during acute exposures (several hours) in crew-like subjects and to determine if additional cognitive domains are sensitive to concentrations of CO2 at, or below, current ISS levels by using a test battery that is currently available onboard ISS. We enrolled 22 volunteers (8 females, 14 males) between the ages of 30-55 (38.8 +/- 7.0) years whose training and professional experience reflect that of the astronaut corps. Subjects were divided among 4 study

  12. Inhalation exposure system used for acute and repeated-dose methyl isocyanate exposures of laboratory animals.

    Science.gov (United States)

    Adkins, B; O'Connor, R W; Dement, J M

    1987-06-01

    Laboratory animals were exposed by inhalation for 2 hr/day (acute) or 6 hr/day (four consecutive days, repeated dose) to methyl isocyanate (MIC). Exposures were conducted in stainless steel and glass inhalation exposure chambers placed in stainless steel, wire mesh cages. MIC was delivered with nitrogen via stainless steel and Teflon supply lines. Chamber concentrations ranged from 0 to 60 ppm and were monitored continuously with infrared spectrophotometers to 1 ppm and at 2-hr intervals to 20 ppb with a high performance liquid chromatograph equipped with a fluorescence detector. Other operational parameters monitored on a continuous basis included chamber temperature (20-27 degrees C), relative humidity (31-64%), static (transmural) pressure (-0.3 in.), and flow (300-500 L/min). The computer-assistance system interfaced with the inhalation exposure laboratory is described in detail, including the analytical instrumentation calibration system used throughout this investigation.

  13. 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...

  14. Biomarkers of Oxidative Stress Study IV. Are Antioxidants Markers of Ozone Exposure?

    Science.gov (United States)

    To determine whether the oxidative effects of ozone would result in losses of antioxidants from plasma, and possibly bronchoalveolar lavage fluid (BALF). This research is part of a comprehensive, multilaboratory validation study searching for noninvasive biomarkers of oxidative ...

  15. 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

  16. Future air quality in Europe: a multi-model assessment of projected exposure to ozone

    Directory of Open Access Journals (Sweden)

    A. Colette

    2012-06-01

    Full Text Available In order to explore future air quality in Europe at the 2030 horizon, two emission scenarios developed in the framework of the Global Energy Assessment including varying assumptions on climate and energy access policies are investigated with an ensemble of six regional and global atmospheric chemistry transport models.

    A specific focus is given in the paper to the assessment of uncertainties and robustness of the projected changes in air quality. The present work relies on an ensemble of chemistry transport models giving insight into the model spread. Both regional and global scale models were involved, so that the ensemble benefits from medium-resolution approaches as well as global models that capture long-range transport. For each scenario a whole decade is modelled in order to gain statistical confidence in the results. A statistical downscaling approach is used to correct the distribution of the model projection. Last, the modelling experiment is linked to a hind-cast study published earlier, where the performances of all participating models were extensively documented.

    The analysis is presented in an exposure-based framework in order to discuss policy relevant changes. According to the emission projections, ozone precursors such as NOx will drop to 30% to 50% of their current levels, depending on the scenario. As a result, annual mean O3 will slightly increase in NOx saturated areas but the overall O3 burden will decrease substantially. Exposure to detrimental O3 levels for health (SOMO35 will be reduced down to 45% to 70% of their current levels. And the fraction of stations where present-day exceedences of daily maximumO3 is higher than 120 μg m-3 more than 25 days per year will drop from 43% down to 2 to 8%.

    We conclude that air pollution mitigation measures (present in both scenarios are the main factors leading to the

  17. The Effect of Chronic Ozone Exposure on the Activation of Endoplasmic Reticulum Stress and Apoptosis in Rat Hippocampus

    Science.gov (United States)

    Rodríguez-Martínez, Erika; Nava-Ruiz, Concepcion; Escamilla-Chimal, Elsa; Borgonio-Perez, Gabino; Rivas-Arancibia, Selva

    2016-01-01

    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 (AD). 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, 78 kDa glucose-regulated protein (GRP78) and caspase 12. It was also subjected to terminal deoxynucleotidyl transferase dUTP nick end labeling (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

  18. 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.

  19. Depression of contraction and the calcium transient in single cardiomyocytes with acute ethanol exposure

    Energy Technology Data Exchange (ETDEWEB)

    Rozanski, D.J.; Delaville, F.J.; Thomas, A.P. (Thomas Jefferson Univ., Philadelphia, PA (United States))

    1992-01-01

    The mechanism by which acute ethanol (ET) exposure causes reversible myocardial dysfunction is unknown. The purpose of this study was to examine the effects of ET exposure on contraction and cytosolic free Ca[sup 2+] ([Ca[sup 2+

  20. Self-reported acute health symptoms and exposure to companion animals

    Science.gov (United States)

    Background: In order to understand the etiological burden of disease associated with acute health symptoms (e.g. gastrointestinal [GI], respiratory, dermatological), it is important to understand how common exposures influence these symptoms. Exposures to familiar and unfamiliar ...

  1. Acute symptoms during non-inhalation exposure to combinations of toluene, trichloroethylene, and n-hexane

    DEFF Research Database (Denmark)

    Bælum, Jesper

    1999-01-01

    To study the acute effect of exposure to a mixture of three commonly used solvents in humans using a route of exposure not involving the nose and lungs, in this case a gastrointestinal application....

  2. Minor effects of long-term ozone exposure on boreal peatland species Eriophorum vaginatum and Sphagnum papillosum

    DEFF Research Database (Denmark)

    Mörsky, SK; Haapala, JK; Rinnan, Riikka;

    2011-01-01

    The effects of long-term ozone fumigation on two common peatland plant species, a sedge Eriophorum vaginatum L. and a moss Sphagnum papillosum Lindb., were studied applying peatland microcosms. The peat cores with intact vegetation were cored from an oligotrophic pine fen and partially embedded...... not show any significant treatment effect in E. vaginatum or in S. papillosum. Total chlorophyll (a + b) concentration tended to increase in early growing season under ozone exposure. During the first growing season, elevated ozone concentration decreased methanol-extractable, UV-absorbing compounds in E...

  3. 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; Csallany, A. Saari; Davies, Michael J.; George, Magdalene M.; Murray, Dennis M.; Roberts, L. Jackson; Shigenaga, Mark K.; Sohal, Rajindar S.; Stocker, Roland; Van Thiel, David H.; Wiswedel, Ingrid; Hatch, Gary E.; Mason, Ronald P.

    2014-01-01

    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, 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 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. PMID:23608465

  4. Infant acute leukemia and maternal exposures during pregnancy.

    Science.gov (United States)

    Pombo-de-Oliveira, Maria S; Koifman, Sergio

    2006-12-01

    Infant acute leukemia (IAL) has a unique profile characterized by the high incidence of translocations involving the MLL gene located at the 11q23 region. To test the potential role of intrauterine and perinatal factors linked to the risk of IAL development, a hospital-based case-control study was conducted in different cities of Brazil. A total of 202 children (ages 0-21 months) with newly diagnosed IAL was enrolled (1999-2005), and 440 age-matched controls were selected from the same hospitals wherein IAL cases were treated. A statistically significant association between maternal use of hormones during pregnancy and IAL was observed [odds ratio (OR), 8.76; 95% confidence interval (95% CI), 2.85-26.93] in a multivariable analysis. The association of certain exposures during pregnancy (hormones, dipyrone, metronidazole, and misoprostol) and MLL gene rearrangements was tested using a case-case approach. Despite the lack of statistical significance, the magnitude of the OR for maternal exposure to dipyrone (OR, 1.45; 95% CI, 0.75-2.86), metronidazole (OR, 1.72; 95% CI, 0.64-4.58), quinolones (OR, 2.25; 95% CI, 0.70-25.70), and hormones (OR, 1.88; 95% CI, 0.50-7.01) may suggest the occurrence of interactions between such maternal exposures during pregnancy and MLL rearrangements, yielding into IAL development. The strong and statistically significant association between IAL and estrogen exposure during pregnancy observed in this study deserves further investigation to investigate its role in intrauterine leukemogenesis.

  5. Acute acid exposure increases rabbit esophageal cell proliferation.

    Science.gov (United States)

    Carpizo, D R; Reaka, A J; Glaws, W R; Pooley, N; Schmidt, L; Halline, A G; Goldstein, J L; Layden, T J

    1998-02-01

    In the present study we examined whether an acute infusion of HCl into the esophagus of rabbits would cause an increase in esophageal cellular proliferation independent of morphologic evidence of cell injury. To examine this question, the distal two thirds of the rabbit esophagus was infused for 1 hour with either 40 mmol/L HCl or NSS (control), and cellular proliferation was studied 24 and 48 hours later by using bromodeoxyuridine (BrDu) to label the nuclei of dividing cells and ornithine decarboxylase (ODC) enzyme activity as a biochemical index of cell division. Although there was no gross or microscopic evidence of cell necrosis or mucosal inflammation 24 hours after H+ infusion, BrDu labeling of basal cell nuclei was significantly greater 24 hours after H+ infusion (31%+/-6%) as compared with that in control animals infused with NSS (15%+/-4%). This increase in labeling index was paralleled by a threefold greater ODC enzyme activity at 24 hours with H+ infusion. Rete pegs were infrequent in control tissues (4+/-4 rete pegs per 100 microm of esophageal length) or in animals examined 24 hours after acid exposure (4+/-2 rete pegs per 100 microm). However, rete pegs were very prominent 48 hours after acid infusion (22+/-6 rete pegs per 100 microm). A short exposure to acid can cause a significant increase in mucosal proliferation independent of injury, suggesting that esophageal cell acidification either directly or indirectly acts as a tissue mitogen.

  6. Sildenafil does not Improve Exercise Capacity under Acute Hypoxia Exposure.

    Science.gov (United States)

    Toro-Salinas, A H; Fort, N; Torrella, J R; Pagès, T; Javierre, C; Viscor, G

    2016-09-01

    The increase in pulmonary arterial pressure (PAP) due to hypoxic pulmonary vasoconstriction (HPV) could be a limiting factor for physical performance during hypoxic exposure. Sildenafil has been shown to reduce PAP in situations of moderate or severe hypoxia, and consequently its role as an ergogenic aid and even a possible doping substance must be considered. We performed a double-blind crossover study to determine the effects of sildenafil on cardiovascular, respiratory and metabolic parameters in normoxia and during acute exposure to hypobaric hypoxia (4 000 m) at rest and during maximal and submaximal (60% VO2 max) exercise tests. One hour before testing started, sildenafil (100 mg) or a placebo was orally administered to 11 volunteers. In normoxic conditions, sildenafil did not affect performance. Similarly, no significant differences were found in cardiovascular and respiratory parameters in hypoxic conditions at rest or during exercise. The use of sildenafil to improve physical performance in non-acclimatized subjects is not supported by our data. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Changes in Cardiac Autonomic Regulation after Acute Lung Exposure to Carbon Nanotubes: Implications for Occupational Exposure

    Directory of Open Access Journals (Sweden)

    Jacopo M. Legramante

    2012-01-01

    Full Text Available Carbon nanotubes (CNTs are among the most relevant engineered nanomaterials (ENMs. Given the expected rise of exposure to ENMs, there is concern that they may adversely affect health of exposed people. Aim of the study was to test the hypothesis that single wall carbon nanotubes (SWCNTs pulmonary exposure acutely affect the autonomic cardiovascular regulation in conscious rats. We studied Wistar-Kyoto rats in which a telemetry transmitter for continuous arterial pressure (AP and heart rate (HR recordings was surgically implanted. SWCNTs dispersed in phosphate buffer saline (PBS or PBS alone were randomly administered intratracheally. Immediately before, and 24 hours after each instillation a 30 min AP recording was performed. The sequence analysis was performed to evaluate the baroreflex function. In the control group, PBS instillation did not induce any significant changes. At variance the SWCNT exposure induced a significant reduction of baroreflex system (BRS (3.5±0.6 versus 2.6±0.40 msec/mmHg without significant changes in the occurrence of baroreflex sequences (7.5±0.47% versus 7.4±0.38%. Our results show that SWCNT pulmonary exposure might affect the cardiovascular autonomic regulation thus contributing to cardiac and arrhythmic events.

  8. Influence of high carbohydrate versus high fat diet in ozone induced pulmonary injury and systemic metabolic impairment in a Brown Norway (BN) rat model of healthy aging

    Science.gov (United States)

    Rationale: Air pollution has been recently linked to the increased prevalence of metabolic syndrome. It has been postulated that dietary risk factors might exacerbate air pollution-induced metabolic impairment. We have recently reported that ozone exposure induces acute systemic ...

  9. The acute effects of preoperative ozone theraphy on surgical wound healing

    OpenAIRE

    Sahin, Hasan; Simsek,Tuncer; Turkon, Hakan; Kalkan,Yıldıray; Ozkul, Faruk; Ozkan,M Turgut Alper; Erbas,Mesut; Altinisik, Ugur; Demiraran, Yavuz

    2016-01-01

    ABSTRACT PURPOSE: To investigate the effects of preoperative rectal ozone insufflation on surgical wound healing over the proinflammatory cytokines and histopathological changes. METHODS: Twenty one rabbits were divided into 3 groups. Sham, surgical wound, and ozone applied (6 sessions, every other day 70 µg/mL in 12 mL O2-O3 mixture rectally) surgical wound groups were created. TNF-alpha and IL-6 levels from all rabbits were studied at the basal, 24th hour, and 72nd hour. The histopatholog...

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

    Energy Technology Data Exchange (ETDEWEB)

    Hofer, Nora; Alexou, Maria [Institute of Forest Botany and Tree Physiology, Chair of Tree Physiology, Albert-Ludwigs-University, Georges-Koehler-Allee 053/054, D-79110 Freiburg (Germany); Heerdt, Christian [Bioclimatology and Air Pollution Research, Department of Ecology, Technische Universitaet Muenchen, Life Science Center Weihenstephan, Am Hochanger 13, 85354 Freising (Germany); Loew, Markus [Ecophysiology of Plants, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Werner, Herbert [Bioclimatology and Air Pollution Research, Department of Ecology, Technische Universitaet Muenchen, Life Science Center Weihenstephan, Am Hochanger 13, 85354 Freising (Germany); Matyssek, Rainer [Ecophysiology of Plants, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Rennenberg, Heinz [Institute of Forest Botany and Tree Physiology, Chair of Tree Physiology, Albert-Ludwigs-University, Georges-Koehler-Allee 053/054, D-79110 Freiburg (Germany); Haberer, Kristine [Institute of Forest Botany and Tree Physiology, Chair of Tree Physiology, Albert-Ludwigs-University, Georges-Koehler-Allee 053/054, D-79110 Freiburg (Germany)], E-mail: kristine.haberer@biologie.uni-freiburg.de

    2008-07-15

    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{sub 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.

  11. Repeated exposure to conditioned fear stress increases anxiety and delays sleep recovery following exposure to an acute traumatic stressor

    Directory of Open Access Journals (Sweden)

    Benjamin N Greenwood

    2014-10-01

    Full Text Available Repeated stressor exposure can sensitize physiological responses to novel stressors and facilitate the development of stress-related psychiatric disorders including anxiety. Disruptions in diurnal rhythms of sleep-wake behavior accompany stress-related psychiatric disorders and could contribute to their development. Complex stressors that include fear-eliciting stimuli can be a component of repeated stress experienced by humans, but whether exposure to repeated fear can prime the development of anxiety and sleep disturbances is unknown. In the current study, adult male F344 rats were exposed to either control conditions or repeated contextual fear conditioning for 22 days followed by exposure to either no, mild (10, or severe (100 acute uncontrollable tail shock stress. Exposure to acute stress produced anxiety-like behavior as measured by a reduction in juvenile social exploration and exaggerated shock-elicited freezing in a novel context. Prior exposure to repeated fear enhanced anxiety-like behavior as measured by shock-elicited freezing, but did not alter social exploratory behavior. The potentiation of anxiety produced by prior repeated fear was temporary; exaggerated fear was present 1 day but not 4 days following acute stress. Interestingly, exposure to acute stress reduced REM and NREM sleep during the hours immediately following acute stress. This initial reduction in sleep was followed by robust REM rebound and diurnal rhythm flattening of sleep / wake behavior. Prior repeated fear extended the acute stress-induced REM and NREM sleep loss, impaired REM rebound, and prolonged the flattening of the diurnal rhythm of NREM sleep following acute stressor exposure. These data suggest that impaired recovery of sleep / wake behavior following acute stress could contribute to the mechanisms by which a history of prior repeated stress increases vulnerability to subsequent novel stressors and stress-related disorders.

  12. Ozone exposure causes a decoupling of conductance and photosynthesis: implications for the Ball-Berry stomatal conductance model.

    Science.gov (United States)

    Lombardozzi, Danica; Sparks, Jed P; Bonan, Gordon; Levis, Samuel

    2012-07-01

    Industrialization has significantly altered atmospheric chemistry by increasing concentrations of chemicals such as nitrogen oxides (NO( x )) and volatile organic carbon, which react in the presence of sunlight to produce tropospheric ozone (O(3)). Ozone is a powerful oxidant that causes both visual and physiological damage to plants, impairing the ability of the plant to control processes like photosynthesis and transpiration. Damage to photosynthesis and stomatal conductance does not always occur at the same rate, which generates a problem when using the Ball-Berry model to predict stomatal conductance because the calculations directly rely on photosynthesis rates. The goals of this work were to develop a modeling framework to modify Ball-Berry stomatal conductance predictions independently of photosynthesis and to test the framework using experimental data. After exposure to elevated O(3) in open-top chambers, photosynthesis and stomatal conductance in tulip poplar changed at different rates through time. We were able to accurately model observed photosynthetic and stomatal conductance responses to chronic O(3) exposure in a Ball-Berry framework by adjusting stomatal conductance in addition to photosynthesis. This led to a significant improvement in the modeled ability to predict both photosynthesis and stomatal conductance responses to O(3).

  13. Serum biomarkers in young adult and aged Brown Norway (BN) rats following episodic (weekly) ozone exposure

    Science.gov (United States)

    Ozone (03) is an air pollutant that is associated with cardiovascular and respiratory diseases. Older adults are considered to be particularly susceptible to oxidant air pollutants such as 03. Serum biomarkers are being sought that would lead to better predictions of susceptibili...

  14. Injury to skeletal muscle of mice following acute and sub-acute pregabalin exposure

    Science.gov (United States)

    Moshiri, Mohammad; Moallem, Seyed Adel; Attaranzadeh, Armin; Saberi, Zahra; Etemad, Leila

    2017-01-01

    Objective(s): Pregabalin (PGB) is a new antiepileptic drug that has received FDA approval for patient who suffers from central neuropathic pain, partial seizures, generalized anxiety disorder, fibromyalgia and sleep disorders. This study was undertaken to evaluate the possible adverse effects of PGB on the muscular system of mice. Materials and Methods: To evaluate the effect of PGB on skeletal muscle, the animals were exposed to a single dose of 1, 2 or 5 g /kg or daily doses of 20, 40 or 80 mg/kg for 21 days, intraperitoneally (IP). Twaenty-four hr after the last drug administration, all animals were sacrificed. The level of fast-twitch skeletal muscle troponin I and CK-MM activity were evaluated in blood as an indicator of muscle injury. Skeletal muscle pathological findings were also reported as scores ranging from 1 to 3 based on the observed lesion. Results: In the acute and sub-acute toxicity assay IP injection of PGB significantly increased the activity and levels of CK-MM and fsTnI compared to the control group. Sub-acute exposure to PGB caused damages that include muscle atrophy, infiltration of inflammatory cells and cell degeneration. Conclusion: PGB administration especially in long term care causes muscle atrophy with infiltration of inflammatory cells and cell degeneration. The fsTnI and CK-MM are reliable markers in PGB-related muscle injury. The exact mechanisms behind the muscular damage are unclear and necessitate further investigations. PMID:28392896

  15. 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...

  16. 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...

  17. Chemical modification of coating of Pinus halepensis pollen by ozone exposure.

    Science.gov (United States)

    Naas, Oumsaad; Mendez, Maxence; Quijada, Melesio; Gosselin, Sylvie; Farah, Jinane; Choukri, Ali; Visez, Nicolas

    2016-07-01

    Pollen coating, located on the exine, includes an extractible lipid fraction. The modification of the pollen coating by air pollutants may have implications on the interactions of pollen with plant stigmas and human cells. Pinus halepensis pollen was exposed to ozone in vitro and the pollen coating was extracted with organic solvent and analyzed by GC-MS. Ozone has induced chemical changes in the coating as observed with an increase in dicarboxylic acids, short-chain fatty acids and aldehydes. 4-Hydroxybenzaldehyde was identified as the main reaction product and its formation was shown to occur both on native pollen and on defatted pollen. 4-Hydroxybenzaldehyde is very likely formed via the ozonolysis of acid coumaric-like monomers constitutive of the sporopollenin. Modification of pollen coating by air pollutants should be accounted for in further studies on effect of pollution on germination and on allergenicity.

  18. Atmospheric protein chemistry influenced by anthropogenic air pollutants: nitration and oligomerization upon exposure to ozone and nitrogen dioxide.

    Science.gov (United States)

    Liu, Fobang; Lakey, Pascale S J; Berkemeier, Thomas; Tong, Haijie; Kunert, Anna Theresa; Meusel, Hannah; Cheng, Yafang; Su, Hang; Fröhlich-Nowoisky, Janine; Lai, Senchao; Weller, Michael G; Shiraiwa, Manabu; Pöschl, Ulrich; Kampf, Christopher J

    2017-08-24

    The allergenic potential of airborne proteins may be enhanced via post-translational modification induced by air pollutants like ozone (O3) and nitrogen dioxide (NO2). The molecular mechanisms and kinetics of the chemical modifications that enhance the allergenicity of proteins, however, are still not fully understood. Here, protein tyrosine nitration and oligomerization upon simultaneous exposure of O3 and NO2 were studied in coated-wall flow-tube and bulk solution experiments under varying atmospherically relevant conditions (5-200 ppb O3, 5-200 ppb NO2, 45-96% RH), using bovine serum albumin as a model protein. Generally, more tyrosine residues were found to react via the nitration pathway than via the oligomerization pathway. Depending on reaction conditions, oligomer mass fractions and nitration degrees were in the ranges of 2.5-25% and 0.5-7%, respectively. The experimental results were well reproduced by the kinetic multilayer model of aerosol surface and bulk chemistry (KM-SUB). The extent of nitration and oligomerization strongly depends on relative humidity (RH) due to moisture-induced phase transition of proteins, highlighting the importance of cloud processing conditions for accelerated protein chemistry. Dimeric and nitrated species were major products in the liquid phase, while protein oligomerization was observed to a greater extent for the solid and semi-solid phase states of proteins. Our results show that the rate of both processes was sensitive towards ambient ozone concentration, but rather insensitive towards different NO2 levels. An increase of tropospheric ozone concentrations in the Anthropocene may thus promote pro-allergic protein modifications and contribute to the observed increase of allergies over the past decades.

  19. Ozone modulates the effects of imipramine on immobility in the forced swim test, and nonspecific parameters of hippocampal oxidative stress in the rat.

    Science.gov (United States)

    Mokoena, Mmalebuso L; Harvey, Brian H; Oliver, Douglas W; Brink, Christiaan B

    2010-06-01

    Depression has been associated with oxidative stress. There is increased awareness of the role of environmental toxins in the development of mood disorders. Ozone, a pro-oxidant and environmental pollutant, has been noted to have central nervous system effects. We investigated the effects of acute and chronic ozone inhalation on the response of imipramine in the forced-swim test (FST) and on biomarkers of oxidative stress in rat hippocampus. Sprague Dawley rats were exposed to 0, 0.25 or 0.7 ppm ozone per inhalation 4 h daily for either 30 days (chronic) or once (acute). Animals were then injected intraperitoneally with imipramine (10 mg/kg) or saline 24, 5 and 1 h before the forced-swim test. Hippocampal superoxide accumulation and lipid peroxidation were measured. Imipramine evoked an antidepressant-like effect independent of acute or chronic ozone exposure. However, 0.7 ppm acute ozone and 0.25 ppm chronic ozone attenuated the antidepressant-like effects of imipramine. The ozone exposures also elevated hippocampal superoxide accumulation and lipid peroxidation. Importantly, imipramine reversed the lipid peroxidation induced by chronic ozone, thereby preventing cellular damage induced by oxidative stress. Ozone exposure presents a feasible model with etiological validity to investigate oxidative stress in depression and antidepressant action.

  20. 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.

  1. 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

  2. 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.

  3. Injury to skeletal muscle of mice following acute and sub-acute pregabalin exposure

    Directory of Open Access Journals (Sweden)

    Mohammad Moshiri

    2017-03-01

    Full Text Available Objective(s: Pregabalin (PGB is a new antiepileptic drug that has received FDA approval for patient who suffers from central neuropathic pain, partial seizures, generalized anxiety disorder, fibromyalgia and sleep disorders. This study was undertaken to evaluate the possible adverse effects of PGB on the muscular system of mice. Materials and Methods: To evaluate the effect of PGB on skeletal muscle, the animals were exposed to a single dose of 1, 2 or 5 g /kg or daily doses of 20, 40 or 80 mg/kg for 21 days, intraperitoneally (IP. Twaenty-four hr after the last drug administration, all animals were sacrificed. The level of fast-twitch skeletal muscle troponin I and CK-MM activity were evaluated in blood as an indicator of muscle injury. Skeletal muscle pathological findings were also reported as scores ranging from 1 to 3 based on the observed lesion. Results: In the acute and sub-acute toxicity assay IP injection of PGB significantly increased the activity and levels of CK-MM and fsTnI compared to the control group. Sub-acute exposure to PGB caused damages that include muscle atrophy, infiltration of inflammatory cells and cell degeneration. Conclusion: PGB administration especially in long term care causes muscle atrophy with infiltration of inflammatory cells and cell degeneration. The fsTnI and CK-MM are reliable markers in PGB-related muscle injury. The exact mechanisms behind the muscular damage are unclear and necessitate further investigations.

  4. Rapid microRNA changes in airways of human volunteers after controlled exposure to air pollutants

    Science.gov (United States)

    Introduction/Rationale: Exposure to air pollutants, including ozone and diesel exhaust (DE) are known to cause acute cardiopulmonary dysfunction; however, the molecular mechanisms underlying these changes remain elusive. One mechanism for rapid regulation of multiple genes is a...

  5. Decreased rates of terpene emissions in Ornithopus compressus L. and Trifolium striatum L. by ozone exposure and nitrogen fertilization.

    Science.gov (United States)

    Llusia, Joan; Bermejo-Bermejo, Victoria; Calvete-Sogo, Héctor; Peñuelas, Josep

    2014-11-01

    Increasing tropospheric ozone (O3) and nitrogen soil availability (N) are two of the main drivers of global change. They both may affect gas exchange, including plant emission of volatiles such as terpenes. We conducted an experiment using open-top chambers to analyze these possible effects on two leguminous species of Mediterranean pastures that are known to have different O3 sensitivity, Ornithopus compressus and Trifolium striatum. O3 exposure and N fertilization did not affect the photosynthetic rates of O. compressus and T. striatum, although O3 tended to induce an increase in the stomatal conductance of both species, especially T. striatum, the most sensitive species. O3 and N soil availability reduced the emission of terpenes in O. compressus and T. striatum. If these responses are confirmed as a general pattern, O3 could affect the competitiveness of these species.

  6. 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

  7. ESTIMATED RATE OF FATAL AUTOMOBILE ACCIDENTS ATTRIBUTABLE TO ACUTE SOLVENT EXPOSURE AT LOW INHALED CONCENTRATIONS

    Science.gov (United States)

    Acute solvent exposures may contribute to automobile accidents because they increase reaction time and decrease attention, in addition to impairing other behaviors. These effects resemble those of ethanol consumption, both with respect to behavioral effects and neurological mecha...

  8. Exposure of bovine dermal tissue to ultraviolet light under the Antarctic ozone hole

    Science.gov (United States)

    Takahashi, Tetsuya; Ogura, Takayuki; Tanaka, Keisuke; Hattori, Shunji; Kudoh, Sakae; Imura, Satoshi

    2016-12-01

    Bovine dermis was exposed outdoors in the Antarctic in 2013 to study the skin damage caused by short-wavelength ultraviolet light under the ozone hole. Collagen was extracted from the exposed dermis with pepsin. The amount of solubilized collagen in the exposed dermis was only 20%-40% of that in dermis shielded from ultraviolet light. The dermis was most difficult to extract when exposed in summer, and then when exposed in spring. Differential scanning calorimetry was used to determine the melting endothermic behavior of the dermal tissue. The peak temperature was highest for the dermis exposed in summer. The exposed dermis was degraded with cyanogen bromide to determine whether cross-linking had occurred. Cross-linked peptides were detected in the dermis exposed in summer or spring, but the dermis exposed in autumn did not differ markedly from the light-shielded dermis. These data show that cross-linkages were readily formed in the collagen molecule chains in dermis exposed to ultraviolet light in summer, when solar elevation is highest and the period of sunshine is longest. A comparison of the dermis exposed in spring and that exposed in autumn showed that cross-linkages were formed more readily by ultraviolet light in spring, when the ozone hole occurred.

  9. Long term exposure to ambient air pollution and incidence of acute coronary events

    DEFF Research Database (Denmark)

    Cesaroni, Giulia; Forastiere, Francesco; Stafoggia, Massimo

    2014-01-01

    To study the effect of long term exposure to airborne pollutants on the incidence of acute coronary events in 11 cohorts participating in the European Study of Cohorts for Air Pollution Effects (ESCAPE).......To study the effect of long term exposure to airborne pollutants on the incidence of acute coronary events in 11 cohorts participating in the European Study of Cohorts for Air Pollution Effects (ESCAPE)....

  10. Estrogen Effects after a Crush Muscle Injury and Acute Exposure to Hypobaric Hypoxia

    Science.gov (United States)

    2015-03-01

    et al. Intermittent hypobaric hypoxia increases the ability of neutrophils to generate superoxide anion in humans. Clin Exp Pharmacol Physiol. 2003...AFRL-SA-WP-TR-2015-0007 Estrogen Effects after a Crush Muscle Injury and Acute Exposure to Hypobaric Hypoxia Dr. Barbara St...after a Crush Muscle Injury and Acute Exposure to Hypobaric Hypoxia 5a. CONTRACT NUMBER FA7014-10-2-0001 5b. GRANT NUMBER 5c. PROGRAM

  11. Ozone exposure and cardiovascular-related mortality in the Canadian Census Health and Environment Cohort (CANCHEC) by spatial synoptic classification zone.

    Science.gov (United States)

    Cakmak, Sabit; Hebbern, Chris; Vanos, Jennifer; Crouse, Dan L; Burnett, Rick

    2016-07-01

    Our objective is to analyse the association between long term ozone exposure and cardiovascular related mortality while accounting for climate, location, and socioeconomic factors. We assigned subjects with 16 years of follow-up in the Canadian Census Health and Environment Cohort (CanCHEC) to one of seven regions based on spatial synoptic classification (SSC) weather types and examined the interaction of exposure to both fine particulate matter (PM2.5) and ground level ozone and cause of death using survival analysis, while adjusting for socioeconomic characteristics and individual confounders. Correlations between ozone and PM2.5 varied across SSC zones from -0.02 to 0.7. Comparing zones using the most populated SSC zone as a reference, a 10 ppb increase in ozone exposure was associated with increases in hazard ratios (HRs) that ranged from 1.007 (95% CI 0.99, 1.015) to 1.03 (95% CI 1.02, 1.041) for cardiovascular disease, 1.013 (95% CI 0.996, 1.03) to 1.058 (95% CI 1.034, 1.082) for cerebrovascular disease, and 1.02 (95% CI 1.006, 1.034) for ischemic heart disease. HRs remained significant after adjustment for PM2.5. Long term exposure to ozone is related to an increased risk of mortality from cardiovascular and cerebrovascular diseases; the risk varies by location across Canada and is not attenuated by adjustment for PM2.5. This research shows that the SSC can be used to define geographic regions and it demonstrates the importance of accounting for that spatial variability when studying the long term health effects of air pollution.

  12. Oxidative stress caused by ozone exposure induces β-amyloid 1-42 overproduction and mitochondrial accumulation by activating the amyloidogenic pathway.

    Science.gov (United States)

    Hernández-Zimbrón, L F; Rivas-Arancibia, S

    2015-09-24

    Oxidative stress is a major risk factor for Alzheimer's disease (AD) that has been suggested to be the trigger of AD pathology. However, whether oxidative damage precedes and contributes directly to the intracellular accumulation of beta amyloid 1-42 (βA42) peptide remains a matter of debate. Chronic exposure to low doses of ozone similar to the levels during a day of high pollution in México City causes a state of oxidative stress that elicits progressive neurodegeneration in the hippocampi of rats. Several reports have demonstrated that the mitochondria are among the first organelles to be affected by oxidative stress and βA42 toxicity and act as sites of the accumulation of βA42, which affects energy metabolism. However, the mechanisms related to the neurodegeneration process and organelle damage that occur in conditions of chronic exposure to low doses of ozone have not been demonstrated. To analyze the effect of chronic ozone chronic exposure on changes in the production and accumulation of the βA42 and βA40 peptides in the mitochondria of hippocampal neurons of rats exposed to ozone, we examined the mitochondrial expression levels of Presenilins 1 and 2 and ADAM10 to detect changes related to the oxidative stress caused by low doses of ozone (0.25ppm). The results revealed significant accumulations of βA42 peptide in the mitochondrial fractions on days 60 and 90 of ozone exposure along with reductions in beta amyloid 1-40 accumulation, significant overexpressions of Pres2 and significant reductions in ADAM10 expression. Beta amyloid immunodetection revealed that there were some intracellular deposits of βA42 and that βA42 and the mitochondrial markers OPA1 and COX1 colocalized. These results indicate that the time of exposure to ozone and the accumulation of βA42 in the mitochondria of the hippocampal cells of rats were correlated. Our results suggest that the accumulation of the βA42 peptide may promote mitochondrial dysfunction due to its

  13. Neurobehavioral development of CD-1 mice after combined gestational and postnatal exposure to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Dell`Omo, G. [Section of Behavioral Pathophysiology, Lab. di Fisiopatologia di Organo e di Sistema, Istituto Superiore di Sanita, Rome (Italy); Fiore, M. [Section of Behavioral Pathophysiology, Lab. di Fisiopatologia di Organo e di Sistema, Istituto Superiore di Sanita, Rome (Italy); Petruzzi, S. [Section of Behavioral Pathophysiology, Lab. di Fisiopatologia di Organo e di Sistema, Istituto Superiore di Sanita, Rome (Italy); Alleva, E. [Section of Behavioral Pathophysiology, Lab. di Fisiopatologia di Organo e di Sistema, Istituto Superiore di Sanita, Rome (Italy); Bignami, G. [Section of Behavioral Pathophysiology, Lab. di Fisiopatologia di Organo e di Sistema, Istituto Superiore di Sanita, Rome (Italy)

    1995-09-01

    Outbred CD-1 mice were exposed continuously to ozone (O{sub 3}, 0.6 ppm) from 6 days prior to the formation of breeding pairs to the time of weaning of the offspring on postnatal day 22 (PND 22) or to PND 26. One half of the mice in each of eight O{sub 3} and eight control litters were subjected on PND 24 to a 20-min open-field test after IP treatment by either saline or scopolamine (2 mg/kg). The remaining mice (those exposed until PND 26) were subjected on PNDs 28-31 to a conditioned place preference (CPP) test, using a short schedule with a single IP injection on PND 29 of either d-amphetamine (3.3 mg/kg) or saline. Subsequently, the saline mice of the open-field experiment were used on PND 59 for an activity test in one of the CPP apparatus compartments after IP treatment by either d-amphetamine (same dose) or saline. In addition, the saline mice of the CPP experiment underwent a multitrial, step-through passive avoidance (PA) acquisition test on PND 59 or 60, followed 24 h later by a single-trial retention test. In the absence of effects on reproductive performance (proportion of successful pregnancies, litter size, offspring viability, and sex ratio), O{sub 3} offspring showed a long-lasting reduction in body weight without modification of sec differences. Ozone effects on neurobehavioral development were not large and quite selective, including: attenuation of the sex differences in several responses (rearing and sniffing in the open-field, activity in the final CPP test session); a change in response choices in the final CPP test, in the absence of a main effect on conditioning; a reduction of grooming in the activity test on PND 29; and impairment of PA acquisition limited to the initial period of training. (orig.)

  14. Age-dependent effect of ozone on pulmonary eicosanoid metabolism in rabbits and rats

    Energy Technology Data Exchange (ETDEWEB)

    Gunnison, A.F.; Finkelstein, I.; Weideman, P.; Su, W.Y.; Sobo, M.; Schlesinger, R.B. (New York Univ. Medical Center, New York (USA))

    1990-11-01

    Acute exposures to ozone have previously been shown to cause quantitative changes in the spectrum of arachidonic acid (AA) metabolites in lung lavage fluid. Since age appears to be an important variable in the toxicity of inhaled ozone, we investigated its effect on ozone-induced changes in pulmonary eicosanoid metabolism. Rats and rabbits ranging in age from neonates to young adults were exposed either to air or to 1 ppm ozone for 2 hr. Lung lavage fluid was collected within 1 hr following exposure and analyzed for its content of selected eicosanoids. In both species, there was a pronounced effect of age on ozone-induced pulmonary eicosanoid metabolism. Ozone-exposed animals at the youngest ages examined had severalfold greater amounts of two products of the cyclooxygenase pathway, prostaglandin E2 (PGE2) and prostaglandin F2 alpha (PGF2 alpha), than did age-matched controls. This effect lessened and eventually disappeared as the animals grew toward adulthood. In rabbits, ozone also induced increases in 6-keto-prostaglandin F1 alpha and thromboxane B2, but these changes were of lesser magnitude and evident only in the youngest rabbits exposed. There was no observed effect of ozone on lung lavage content of leukothriene B4. Indices of nonspecific pulmonary damage, i.e., protein concentration in lung lavage fluid and total number and viability of lavaged lung cells, were affected by ozone exposure, but not in an age-dependent manner that correlated with changes in pulmonary eicosanoid metabolism. In vitro ozone exposure of lung macrophages from naive rabbits of the same age range as those exposed in vivo demonstrated that ozone is capable of stimulating the elaboration of PGF2 alpha and especially PGE2. However, the increase in lavage fluid PGE2 and PGF2 alpha caused by ozone inhalation could not be attributed to macrophage metabolism conclusively.

  15. Time-dependent changes of markers associated with inflammation in the lungs of humans exposed to ambient levels of ozone

    Energy Technology Data Exchange (ETDEWEB)

    Koren, H.S.; Devlin, R.B.; Becker, S.; Perez, R.; McDonnell, W.F.

    1991-01-01

    Acute exposure of humans to 0.4 ppm ozone results in reversible respiratory function decrements, and cellular and biochemical changes leading to the production of substances which can mediate inflammation and acute lung injury. The purpose of the study was to determine whether inflammatory changes occur relatively rapidly (within 1h) following exposure to ozone, or if the cascade of events which are initiated by ozone and lead to inflammation, take some time to develop. The authors exposed 10 healthy volunteers twice: once to filtered air and once to 0.4 ppm ozone. Each exposure lasted for 2h at an exercise level of 60 1/min, and bronchoalveolar lavage was performed 1h following exposure. The data from the study were exposed to 03 under identical conditions except that bronchoalveolar lavage was performed 18h following exposure. The results of the present study demonstrate that 03 is capable of inducing rapid cellular and biochemical changes in the lung. These changes were detectable as early as 1h following a 2h exposure of humans to ozone. The profiles of these changes were different at 1h and 18h following ozone exposures. Bronchoalveolar lavage fluid had levels of neutrophils, IL-6, and prostaglandin E2 that were higher at 1h than at 18h post exposure.

  16. AGE-RELATED TOXICITY PATHWAY ANALYSIS IN BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    Science.gov (United States)

    The influence of aging on susceptibility to environmental exposures is poorly understood. To investigate-the contribution of different life stages on response to toxicants, we examined the effects of an acute exposure to the volatile organic compound, toluene (0.0 or 1.0 g/kg), i...

  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. In vitro and in vivo models of acute alcohol exposure

    Institute of Scientific and Technical Information of China (English)

    Angela Dolganiuc; Gyongyi Szabo

    2009-01-01

    Alcohol abuse is a global problem due to the financial burden on society and the healthcare system. While the harmful health effects of chronic alcohol abuse are well established, more recent data suggest that acute alcohol consumption also affects human wellbeing. Thus, there is a need for research models in order to fully understand the effect of acute alcohol abuse on different body systems and organs. The present manuscript summarizes the interdisciplinary advantages and disadvantages of currently available human and non-human models of acute alcohol abuse,and identifies their suitability for biomedical research.

  19. BEAS S6 (BEAS) human bronchial epithelial cells produce inflammatory mediators following ozone(O sub 3 ) exposure

    Energy Technology Data Exchange (ETDEWEB)

    McKinnon, K.; Joyce, M.; Noah, T.; Devlin, R.; Koren, H. (Univ. of North Carolina, Chapel Hill (United States) Environmental Protection Agency, Research Triangle Park, NC (United States))

    1991-03-11

    Ozone induces an inflammatory response in humans. The purpose of this study was to assess the role of epithelial cells in this response. The authors exposed the bronchial epithelial cell line BEAS cultured on collagen-impregnated filters to air or varying concentrations of O{sub 3}. Fluid obtained from either apical or basolateral compartments was analyzed for various inflammatory mediators and other products released in response to O{sub 3} exposure. O{sub 3} had dose-dependent cytotoxic effects as determined by the release of LDH or {sup 51}Cr and by uptake of trypan blue or propidium iodide. PGE{sub 2}, leukotrienes C{sub 4}, B{sub 4}, and E{sub 4}, fibronectin, PAF, and IL 6 were produced in dose-dependent responses following exposure of BEAS cells to 0.1 to 1.0 ppm O{sub 3}. The data demonstrate that the BEAS cell line produces inflammatory substances in response to O{sub 3} and thus functions as a useful model to study pollutant/airway cell interactions.

  20. Clover as a tool for bioindication of phytotoxic ozone--5 years of experience from southern Sweden--consequences for the short-term critical levels.

    Science.gov (United States)

    Karlsson, Gunilla Pihl; Karlsson, Per Erik; Danielsson, Helena; Pleijel, Håkan

    2003-01-01

    Critical levels (CLs) for ozone effects on plants in Europe have been defined within the UN-ECE Convention on Long-Range Transboundary Air Pollution, CLRTAP. The purpose of the short-term CLs is to ensure protection of all crops to acute ozone injury. The currently used CLs are based on the ozone exposure of the plants during daylight hours expressed as AOT40 (Accumulated exposure Over the Threshold 40 nmol mol(-1) ozone). The aims of this study were: to test the performance of the current short-term CLs, to test alternative ozone exposure indices and to test if changes in the ozone cut-off concentration, the inclusion of a lag-period (LP) between exposure and identification of visible ozone injury or the duration of the ozone integration period improved the performance of the exposure index. The analysis was based on 38 different datasets from experiments with subterranean clover, Trifolium subterraneum in southern Sweden. AOT indices generally performed better than averaged ozone concentrations or SUM (Sum of ozone concentrations when a threshold is exceeded) indices. Regression analysis showed that the current short-term CL, AOT40 with a VPD (water vapour pressure deficit) threshold of 1.5 kPa, explained 56% of the variation in visible injury. A longer exposure period and the introduction of a LP, admitting visible ozone injury time to develop after exposure, improved the performance of the exposure index. AOT30 accumulated over 10 days before harvest, excluding a LP of 3 days before injury observation, performed best and explained 88% of the variation in visible injury. AOT40 indices left a rather large amount of visible injury unexplained indicating that a lower cut-off concentration for ozone is preferable. The results of the investigation indicated that a visible injury threshold of 10% improved the distinction between harmful and less harmful exposure.

  1. Effects of acute electromagnetic fields exposure on the interhemispheric homotopic functional connectivity during resting state.

    Science.gov (United States)

    Lv, Bin; Shao, Qing; Chen, Zhiye; Ma, Lin; Wu, Tongning

    2015-08-01

    In this paper, we aimed to investigate the possible effects of acute radiofrequency electromagnetic fields (EMF) on the interhemispheric homotopic functional connectivity with resting state functional magnetic resonance imaging (fMRI) technique. We designed a controllable LTE-related EMF exposure environment at 2.573 GHz and performed the 30 min real/sham exposure experiments on human brain under the safety limits. The resting state fMRI signals were collected before and after EMF exposure. Then voxel-mirrored homotopic connectivity method was utilized to evaluate the acute effects of LTE EMF exposure on the homotopic functional connectivity between two human hemispheres. Based on our previous research, we further demonstrated that the 30 min short-term LTE EMF exposure would modulate the interhemispheric homotopic functional connectivity in resting state around the medial frontal gyrus and the paracentral lobule during the real exposure.

  2. Calcium-dependent behavioural responses to acute copper exposure in Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Poulsen, S.B.; Svendsen, Jon Christian; Aarestrup, Kim;

    2014-01-01

    Using rainbow trout Oncorhynchus mykiss, the present study demonstrated that: (1) calcium (Ca) increased the range of copper (Cu) concentrations that O. mykiss avoided; (2) Ca conserved the maintenance of pre-exposure swimming activity during inescapable acute (10 min) Cu exposure. Data showed...... their spontaneous swimming speed, whereas no response was observed in O. mykiss acclimated and tested at high Ca concentration. Collectively, the data support the conclusion that in O. mykiss the behavioural responses to acute Cu exposure are Ca-dependent....

  3. Genome-wide Gene Expression Profiling of Acute Metal Exposures in Male Zebrafish

    Science.gov (United States)

    2014-10-23

    and methods Experimental overview Fig. 1 shows the design scheme. Fish exposures Briefly, adult,male zebrafishwere exposed to concentrations of each...before and after exposures. Initially 25 adult (6–9 months) presumptive male zebrafish were selected per condition to ensure that 20 male fish were...evaluated in whole adult male zebra ???sh following acute 24 h high dose exposure to three metals with known human health risks. Male adult zebra ???sh

  4. Effects of ozone exposure on lipid metabolism in human alveolar macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, M.; Madden, M.C.; Samet, J.M.; Koren, H.S.

    1991-01-01

    Alveolar macrophages (AM) store arachidonic acid (AA) which is esterified in cellular phospholipids until liberated by phospholipase A2 or C after exposure to inflammatory stimuli. Following release, there can be subsequent metabolism of AA into various potent, biological active mediators including prostaglandins and platelet activating factor (PAF). To examine the possibility that these mediators may account for some of the pathophysiologic alterations seen in the lung following O3 exposure, human AM were collected by bronchoalveolar lavage of normal subjects, plated into tissue culture dishes, and the adherent cells were incubated with 3H-AA or 3H-lysoPAF. Human AM exposed 1.0 ppm O3 for 2 hr released 65 + or - 12% more tritium, derived from 3H-AA, than paired air-exposed controls into media supernatants. In other studies using a similar O3 exposure protocol, there was also a significant increase in human AM PGE2 production (2.0 + or - 0.5 fold-increase above air-exposure values, p<0.01, n=17). In additional studies, using a similar O3 exposure protocol (1.0 ppm for 1 hr), there was also a significant increase in human AM PAF content (1.7 + or - 0.2 fold-increase above air-exposure values, p<0.02, n=5).

  5. A Bayesian model for quantifying the change in mortality associated with future ozone exposures under climate change.

    Science.gov (United States)

    Alexeeff, Stacey E; Pfister, Gabriele G; Nychka, Doug

    2016-03-01

    Climate change is expected to have many impacts on the environment, including changes in ozone concentrations at the surface level. A key public health concern is the potential increase in ozone-related summertime mortality if surface ozone concentrations rise in response to climate change. Although ozone formation depends partly on summertime weather, which exhibits considerable inter-annual variability, previous health impact studies have not incorporated the variability of ozone into their prediction models. A major source of uncertainty in the health impacts is the variability of the modeled ozone concentrations. We propose a Bayesian model and Monte Carlo estimation method for quantifying health effects of future ozone. An advantage of this approach is that we include the uncertainty in both the health effect association and the modeled ozone concentrations. Using our proposed approach, we quantify the expected change in ozone-related summertime mortality in the contiguous United States between 2000 and 2050 under a changing climate. The mortality estimates show regional patterns in the expected degree of impact. We also illustrate the results when using a common technique in previous work that averages ozone to reduce the size of the data, and contrast these findings with our own. Our analysis yields more realistic inferences, providing clearer interpretation for decision making regarding the impacts of climate change.

  6. 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.

  7. Sensitivity of Trout to Chronic Acute Exposure to Selenium

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Gissel; Nielsen, M. Gissel

    1978-01-01

    Trout were exposed to selenite (Na2SeO3) solutions of varying concentrations (0.1-100 ppm Se) for periods of up to 4 wk. A chronic exposure to 0.1 ppm Se or less is non-lethal to trout. Lethality at higher concentrations depends on the length of exposure. Trout that survive for 10 days in tap...

  8. Foliar responses of five plant species to ozone and a sulphur dioxide/ozone mixture after a sulphur dioxide pre-exposure

    Science.gov (United States)

    Hofstra, G.; Beckerson, D. W.

    Plants that were pretreated with 0.15 ppm SO 2 for either 2 or 3 d before an intermittent O 3 or SO 2/O 3 exposure exhibited differences in per cent visible foliar injury that often varied significantly from plants that received no SO 2 pretreatment. Differences that were observed could not be explained on the basis of leaf diffusive resistance alone. The SO 2 pretreatment for 2 d caused a decrease in visible O 3 injury in white bean, an increase in visible O 3 injury in cucumber and radish, and had no effect on soybean and tomato. The same pretreatment caused an increase in visible injury from the SO 2/O 3 mixture in white bean, a decrease in visible injury for cucumber and tomato, and had no effect on soybean and radish. However, these same trends did not occur when the SO 2 pretreatment was increased to 3 d. Pretreatment with sub-acute levels of SO 2 can significantly alter a plant's response to O 3 or a mixture of SO 2/O 3, the change in response being sensitive to the pretreatment SO 2 dosage. The nature of the visible injury symptoms from O 3 or the pollutant mixture were not altered for any of the plant species regardless of the length of time of the SO 2 pretreatment and, generally, the onset of visible injury was not greatly altered.

  9. Acute expanded perlite exposure with persistent reactive airway dysfunction syndrome.

    Science.gov (United States)

    Du, Chung-Li; Wang, Jung-Der; Chu, Po-Chin; Guo, Yue-Liang Leon

    2010-01-01

    Expanded perlite has been assumed as simple nuisance, however during an accidental spill out in Taiwan, among 24 exposed workers followed for more than 6 months, three developed persisted respiratory symptoms and positive provocation tests were compatible with reactive airway dysfunction syndrome. During simulation experiment expanded perlite is shown to be very dusty and greatly exceed current exposure permission level. Review of literature and evidence, though exposure of expanded perlite below permission level may be generally safe, precautionary protection of short term heavy exposure is warranted.

  10. Growth of Chironomus dilutus larvae exposed to ozone-treated and untreated oil sands process water

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, J.; Wiseman, S.; Franz, E.; Jones, P.; Liber, K.; Giesy, J. [Saskatchewan Univ., Saskatoon, SK (Canada); Gamal El-Din, M.; Marin, J. [Alberta Univ., Edmonton, AB (Canada)

    2010-07-01

    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{sub 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{sub 3}/L ozonated OSPW was not much different from that of the controls. Larvae exposed to 80 mg O{sub 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.

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

    Science.gov (United States)

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

    2017-02-01

    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 ≤2.5µm (PM2.5) and ozone during early gestation was associated with a higher prevalence of orofacial clefts. 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 PM2.5 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. Each 10µg/m(3) increase in PM2.5 concentration was significantly associated with cleft palate alone (OR =1.43, 95% CI: 1.11-1.86). There was no significant association between PM2.5 concentration and cleft lip with or without cleft palate. No associations were observed between ozone exposure and the two outcomes of orofacial clefts. Our study suggests that PM2.5 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. Published by Elsevier Inc.

  12. Pulmonary CT findings in acute mercury vapour exposure

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Manabu; Sato, Kimihiko; Heianna, Jyouiti; Hirano, Yoshinori; Omachi, Kohiti; Izumi, Jyunichi; Watarai, Jiro

    2001-01-01

    AIM: We describe the pulmonary computed tomography (CT) findings in acute mercury poisoning. MATERIALS AND METHODS: Initial (n= 8) and follow-up (n= 6) chest CT examinations in eight patients exposed to mercury vapour while cutting pipes in a sulphuric acid plant were reviewed. Of the eight patients, two were asymptomatic and had normal CT results, two were asymptomatic but had abnormalities on CT, and four had both acute symptoms and positive CT results. The patients were all men whose ages ranged from 37 to 54 years (mean, 49 years). RESULTS: Poorly defined nodules were present in five of six patients with positive CT findings, present alone in two patients or as part of a mixed pattern in three. They were random in distribution. Alveolar consolidation (n= 3) and areas of ground-glass opacity (n= 4) were observed and were more prominent in the most severely affected patients with the highest blood and urine level of mercury, predominantly in the upper and/or middle zone. These abnormal findings on CT resolved with (n= 1) or without (n= 5) steroid therapy. Pathological findings (n= 1) demonstrated acute interstitial changes predominantly with oedema. CONCLUSION: We report CT findings in eight patients acutely exposed to mercury vapour. The pulmonary injury was reversible on CT in these cases. Hashimoto, M. (2001)

  13. A novel antibody-based biomarker for chronic algal toxin exposure and sub-acute neurotoxicity

    Science.gov (United States)

    Lefebvre, Kathi A.; Frame, Elizabeth R.; Gulland, Frances; Hansen, John D.; Kendrick, Preston S.; Beyer, Richard P.; Bammler, Theo K.; Farin, Frederico M.; Hiolski, Emma M.; Smith, Donald R.; Marcinek, David J.

    2012-01-01

    The neurotoxic amino acid, domoic acid (DA), is naturally produced by marine phytoplankton and presents a significant threat to the health of marine mammals, seabirds and humans via transfer of the toxin through the foodweb. In humans, acute exposure causes a neurotoxic illness known as amnesic shellfish poisoning characterized by seizures, memory loss, coma and death. Regular monitoring for high DA levels in edible shellfish tissues has been effective in protecting human consumers from acute DA exposure. However, chronic low-level DA exposure remains a concern, particularly in coastal and tribal communities that subsistence harvest shellfish known to contain low levels of the toxin. Domoic acid exposure via consumption of planktivorous fish also has a profound health impact on California sea lions (Zalophus californianus) affecting hundreds of animals yearly. Due to increasing algal toxin exposure threats globally, there is a critical need for reliable diagnostic tests for assessing chronic DA exposure in humans and wildlife. Here we report the discovery of a novel DA-specific antibody response that is a signature of chronic low-level exposure identified initially in a zebrafish exposure model and confirmed in naturally exposed wild sea lions. Additionally, we found that chronic exposure in zebrafish caused increased neurologic sensitivity to DA, revealing that repetitive exposure to DA well below the threshold for acute behavioral toxicity has underlying neurotoxic consequences. The discovery that chronic exposure to low levels of a small, water-soluble single amino acid triggers a detectable antibody response is surprising and has profound implications for the development of diagnostic tests for exposure to other pervasive environmental toxins.

  14. Model of risk of cortical cataract in the US population with exposure to increased ultraviolet radiation due to stratospheric ozone depletion.

    Science.gov (United States)

    West, Sheila K; Longstreth, Janice D; Munoz, Beatriz E; Pitcher, Hugh M; Duncan, Donald D

    2005-12-01

    The authors modeled the possible consequences for US cataract incidence of increases in ultraviolet B radiation due to ozone depletion. Data on the dose-response relation between ocular exposure to ultraviolet B radiation and cortical cataract were derived from a population-based study (the Salisbury Eye Evaluation Project, Salisbury, Maryland) in which extensive data on cataract and ultraviolet radiation were collected in persons aged 65-84 years. Exposure estimates for the US population were derived using estimated ultraviolet radiation fluxes as a function of wavelength. US Census data were used to obtain the age, ethnicity, and sex distribution of the population. Predicted probabilities of cataract were derived from the age-, sex-, and ethnicity-specific ocular ultraviolet exposure data and were modeled under conditions of 5-20% ozone depletion. The analysis indicated that by 2050, the prevalence of cortical cataract will increase above expected levels by 1.3-6.9%. The authors estimate that with 5-20% ozone depletion, there will be 167,000-830,000 additional cases of cortical cataract by 2050. Because of the high prevalence of cataract in older persons, at a 2003 cost of 3,370 dollars per cataract operation, this increase could represent an excess cost of 563 million dollars to 2.8 billion dollars.

  15. The Role of Underlying Type 2 Diabetes Mellitus and Obesity in Ozone-Induced Pulmonary Injury and Metabolic Impairment

    Science.gov (United States)

    RATIONALE: A growing body of evidence indicates an association between air pollution exposure and metabolic disorders such as obesity and type 2 diabetes mellitus (T2DM). We have recently demonstrated that an acute exposure to ozone in metabolically normal rat strains produces h...

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

    Science.gov (United States)

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

    2015-11-01

    This is the longest continuous experiment where ethylenediurea (EDU) was used to protect plants from ozone (O3). Effects of long-term ambient O3 exposure (23 ppm h AOT40) on biomass of an O3 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 O3 although the effect was significant only for stem and coarse roots. Ambient O3 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 O3 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.

  17. The effect of ozone exposure on rat alveolar macrophage arachidonic acid metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Madden, M.C.; Eling, T.E.; Dailey, L.A.; Friedman, M. (Univ. of North Carolina, Chapel Hill (USA))

    1991-01-01

    Rat alveolar macrophages were prelabeled with {sup 3}H-arachidonic acid ({sup 3}H-AA) and exposed to air or O3 (0.1-1.0 ppm) in vitro for 2 h. Alveolar macrophages released 3.6-fold more tritium at the 1.0 ppm exposure concentration compared with air-exposed macrophages. A significantly increased production of several {sup 3}H-AA metabolites, including 6-keto-PGF1 alpha, thromboxane B2, 12-hydroxy-5,8,10-heptadecatrienoic acid, prostaglandins E2 and D2, leukotrienes B4 and D4, and 15-hydroxyeicosatetraenoic acid was formed by macrophages exposed to 1.0 ppm O3 compared with air-exposed macrophages as determined by high performance liquid chromatography (HPLC) analysis. O3 exposure did not alter macrophage {sup 3}H-AA metabolism in response to calcium ionophore A23187. The largest tritiated peak observed in the HPLC chromatograms of O{sub 3}-exposed cells was a polar complex of products that contained various phospholipids and neutral lipids (including diacylglycerol) and possibly degradation products of {sup 3}H-AA and some of its metabolites. These changes in macrophage arachidonic acid metabolism may play an important role in the lung response to O{sub 3} exposure in vivo.

  18. Prenatal and acute cocaine exposure affects neural responses and habituation to visual stimuli

    Directory of Open Access Journals (Sweden)

    Elizabeth Brooke Riley

    2015-08-01

    Full Text Available Psychostimulants have many effects on visual function, from adverse, following acute and prenatal exposure to therapeutic, on attention deficit. To determine the impact of prenatal and acute cocaine exposure on visual processing, we studied neuronal responses to visual stimuli in two brain regions of a transgenic larval zebrafish expressing the calcium indicator GCaMP-HS. We found that both red light (LF and dark (DF flashes elicited similar responses in the optic tectum neuropil (TOn, while the dorsal telencephalon (dTe responded only to LF. Acute cocaine (0.5 μM reduced neuronal responses to LF in both brain regions but did not affect responses to DF. Repeated stimulus presentation led to habituation of dTe neurons to LF. Acute cocaine prevented habituation. TOn habituated to DF, but not LF, and DF habituation was not modified by cocaine. Remarkably, prenatal cocaine exposure prevented the effects of acute cocaine on LF response amplitude and habituation later in development in both brain regions, but did not affect DF responses. We discovered that, in spite of similar neural responses to LF and DF in the TO (superior colliculus in mammals, responses to LF are more complex, involving dTe (homologous to the cerebral cortex, and are more vulnerable to cocaine. Our results demonstrate that acute cocaine exposure affects visual processing differentially by brain region, and that prenatal cocaine exposure modifies zebrafish visual processing in multiple structures in a stimulus-dependent manner. These findings are in accordance with the major role that the optic tectum and cerebral cortex play in sustaining visual attention, and support the hypothesis that modification of these areas by prenatal cocaine exposure may be responsible for visual deficits noted in humans. This model offers new methodological approaches for studying the adverse and therapeutic effects of psychostimulants on attention, and for the development of new pharmacological

  19. Behavioral and neurochemical changes in response to acute stressors: influence of previous chronic exposure to immobilization.

    Science.gov (United States)

    Pol, O; Campmany, L; Gil, M; Armario, A

    1992-07-01

    The effect of daily (2 h) exposure to immobilization (IMO) for 15 days on the behavioral and neurochemical responses of adult male rats to acute stress caused by 2-h IMO or 2-h tail-shock was studied. The brain areas studied were frontal cortex, hippocampus, hypothalamus, midbrain, and pons plus medulla. Chronic exposure to IMO did not alter noradrenaline (NA), 3-methoxy,4-hydroxyphenyletileneglycol-SO4 (MHPG-SO4), serotonin, or 5-hydroxindoleacetic acid (5-HIAA) concentrations in any brain area as measured approximately 20 h after the last exposure to IMO. Exposure to behavioral tests did not modify neurochemical variables except NA levels in the hypothalamus of nonchronically stressed (control) rats. Both exposure to 2-h IMO or 2-h shock significantly decreased NA levels in hypothalamus and midbrain of nonchronically stressed rats. These decreases in response to the two acute stressors were not observed in chronically stressed rats. However, MHPG-SO4 levels increased to the same extent in control and chronically stressed rats after exposure to the acute stressors. Likewise, increased 5-HIAA concentrations observed in response to acute stressors were similar in control and chronically stressed rats. The inhibition of activity (areas crossed and rearing) in the holeboard caused by acute IMO was less marked in rats previously exposed to the same stressor than in control rats, but the response to shock was similar. In the forced swim test, acute IMO decreased struggling in control rats but tended to increase it in chronically stressed rats. The response to shock followed the same pattern as that to IMO, although it was slight.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Catalase Activity in Brown Mussels (Perna perna) under Acute Cadmium, Lead, and Copper Exposure and Depuration Tests

    National Research Council Canada - National Science Library

    Boudjema, Kamel; Kourdali, Sidali; Bounakous, Nabila; Meknachi, Abdellah; Badis, Abdelmalek

    2014-01-01

      Brown mussels (Perna perna) were exposed to cadmium (Cd), lead (Pb), and copper (Cu) concentrations under acute exposure and exposure-depuration tests for the estimation of biochemical biomarker catalase...

  1. Impact of acute and chronic inhalation exposure to CdO nanoparticles on mice

    OpenAIRE

    Lebedová, J.; Bláhová, L.; Večeřa, Z. (Zbyněk); P. Mikuška; Dočekal, B. (Bohumil); Buchtová, M. (Marcela); Míšek, I. (Ivan); Dumková, J.; Hampl, A.; Hilscherová, K.

    2016-01-01

    Cadmium nanoparticles can represent a risk in both industrial and environmental settings, but there is little knowledge on the impacts of their inhalation, especially concerning longer-term exposures. In this study, mice were exposed to cadmium oxide (CdO) nanoparticles in whole body inhalation chambers for 4 to 72 h in acute and 1 to 13 weeks (24 h/day, 7 days/week) in chronic exposure to investigate the dynamics of nanoparticle uptake and effects. In the acute experiment, mice were ...

  2. Acute exposure to silica nanoparticles aggravate airway inflammation: different effects according to surface characteristics

    OpenAIRE

    Park, Hye Jung; Sohn, Jung-Ho; Kim, Yoon-Ju; Park, Yoon Hee; Han, Heejae; Park, Kyung Hee; Lee, Kangtaek; Choi, Hoon; Um, Kiju; Choi,In-Hong; Park, Jung-Won; Lee, Jae-Hyun

    2015-01-01

    Silica nanoparticles (SNPs) are widely used in many scientific and industrial fields despite the lack of proper evaluation of their potential toxicity. This study examined the effects of acute exposure to SNPs, either alone or in conjunction with ovalbumin (OVA), by studying the respiratory systems in exposed mouse models. Three types of SNPs were used: spherical SNPs (S-SNPs), mesoporous SNPs (M-SNPs), and PEGylated SNPs (P-SNPs). In the acute SNP exposure model performed, 6-week-old BALB/c ...

  3. Acute and chronic effects from pulse exposure of D. magna to silver and copper oxide nanoparticles.

    Science.gov (United States)

    Sørensen, Sara Nørgaard; Holten Lützhøft, Hans-Christian; Rasmussen, Rose; Baun, Anders

    2016-11-01

    Aquatic toxicity testing of nanoparticles (NPs) is challenged by their dynamic behavior in test suspensions. The resulting difficulties in controlling and characterizing exposure concentrations are detrimental to the generation of concentration-response data needed for hazard identification of NPs. This study explores the applicability of short-term (1, 2 and 3h) pulse exposures as means to keep the exposure stable and at the same time disclose acute and chronic effects of AgNPs and CuONPs in D. magna. Dissolution, agglomeration and sedimentation were found to have less influence on exposure concentrations during 1-3h pulses than for 24-48h continuous exposures. For AgNPs, preparation of test suspensions in medium 24h before toxicity testing (aging) increased stability during the short-term pulses. In pulse tests, organisms were exposed to the test materials, AgNPs and CuONPs for 1, 2 and 3h, and afterwards transferred to clean medium and observed for 48h (post-exposure period) for acute effects and for 21 d for chronic effects. AgNO3 and CuCl2 were used as reference materials for dissolved silver and copper, respectively. For all test materials, a 3h pulse caused comparable immobility in D. magna (observed after 48h post-exposure) as 24h continuous exposure, as evidenced by overlapping 95% confidence intervals of EC50-values. In the 21 d post-exposure period, no trends in mortality or body length were identified. AgNP and AgNO3 pulses had no effect on the number of moltings, days to first live offspring or cumulated number of offspring, but the number of offspring increased for AgNPs (3h pulse only). In contrast, CuONP and CuCl2 pulses decreased the number of moltings and offspring, and for CuONPs the time to first live offspring was prolonged. After CuONP exposures, the offspring production decreased more with increasing concentrations than for CuCl2 exposures when taking the measured dissolved copper into account. This indicates a nanoparticle-specific effect

  4. Commuters’ air pollution exposure and acute health effects

    NARCIS (Netherlands)

    Zuurbier, M.M.M.

    2011-01-01

    People spend a substantial proportion of their time in traffic. In Europe, the average daily time in traffic is one to one and a half hour. Because of high in-traffic exposures and because most of the journeys are made during rush hours, the one to one and a half hour in traffic contributes dispropo

  5. Commuters’ air pollution exposure and acute health effects

    NARCIS (Netherlands)

    Zuurbier, M.M.M.

    2011-01-01

    People spend a substantial proportion of their time in traffic. In Europe, the average daily time in traffic is one to one and a half hour. Because of high in-traffic exposures and because most of the journeys are made during rush hours, the one to one and a half hour in traffic contributes

  6. Ozone-induced injury and oxidative stress in bronchiolar epithelium are associated with altered pulmonary mechanics.

    Science.gov (United States)

    Sunil, Vasanthi R; Vayas, Kinal N; Massa, Christopher B; Gow, Andrew J; Laskin, Jeffrey D; Laskin, Debra L

    2013-06-01

    In these studies, we analyzed the effects of ozone on bronchiolar epithelium. Exposure of rats to ozone (2 ppm, 3 h) resulted in rapid (within 3 h) and persistent (up to 72 h) histological changes in the bronchiolar epithelium, including hypercellularity, loss of cilia, and necrotizing bronchiolitis. Perivascular edema and vascular congestion were also evident, along with a decrease in Clara cell secretory protein in bronchoalveolar lavage, which was maximal 24 h post-exposure. Ozone also induced the appearance of 8-hydroxy-2'-deoxyguanosine, Ym1, and heme oxygenase-1 in the bronchiolar epithelium. This was associated with increased expression of cleaved caspase-9 and beclin-1, indicating initiation of apoptosis and autophagy. A rapid and persistent increase in galectin-3, a regulator of epithelial cell apoptosis, was also observed. Following ozone exposure (3-24 h), increased expression of cyclooxygenase-2, inducible nitric oxide synthase, and arginase-1 was noted in bronchiolar epithelium. Ozone-induced injury and oxidative stress in bronchiolar epithelium were linked to methacholine-induced alterations in pulmonary mechanics. Thus, significant increases in lung resistance and elastance, along with decreases in lung compliance and end tidal volume, were observed at higher doses of methacholine. This indicates that ozone causes an increase in effective stiffness of the lung as a consequence of changes in the conducting airways. Collectively, these studies demonstrate that bronchiolar epithelium is highly susceptible to injury and oxidative stress induced by acute exposure to ozone; moreover, this is accompanied by altered lung functioning.

  7. Humoral immunodepression following acute NO/sub 2/ exposure in normal and adrenalectomized mice

    Energy Technology Data Exchange (ETDEWEB)

    Azoulay-Dupuis, E.; Levacher, M.; Muffat-Joly, M.; Pocidalo, J.J.

    1985-01-01

    The effects following 20 ppm NO/sub 2/ exposure on humoral immunity were investigated in C57BI/6 mice after 48, 72, and 96 h exposure. Both spleen plaque-forming cell (PFC) responses and serum hemagglutinins (HA) using sheep red blood cells (SRBC) as antigen were studied. Splenic and thymic weight and cellularity decreased on acute exposure to NO/sub 2/. PFC were markedly depressed after 48 h exposure and continued to decrease as exposure time was lengthened. HA titers were also depressed. The same significant suppression of PFC and HA titers was observed in adrenalectomized mice after 96 h NO/sub 2/ exposure. The depression of humoral immunity in NO/sub 2/-exposed mice was independent of stress-induced endogeneous steroids.

  8. Chronic and acute effects of coal tar pitch exposure and cardiopulmonary mortality among aluminum smelter workers.

    Science.gov (United States)

    Friesen, Melissa C; Demers, Paul A; Spinelli, John J; Eisen, Ellen A; Lorenzi, Maria F; Le, Nhu D

    2010-10-01

    Air pollution causes several adverse cardiovascular and respiratory effects. In occupational studies, where levels of particulate matter and polycyclic aromatic hydrocarbons (PAHs) are higher, the evidence is inconsistent. The effects of acute and chronic PAH exposure on cardiopulmonary mortality were examined within a Kitimat, Canada, aluminum smelter cohort (n = 7,026) linked to a national mortality database (1957-1999). No standardized mortality ratio was significantly elevated compared with the province's population. Smoking-adjusted internal comparisons were conducted using Cox regression for male subjects (n = 6,423). Ischemic heart disease (IHD) mortality (n = 281) was associated with cumulative benzo[a]pyrene (B(a)P) exposure (hazard ratio = 1.62, 95% confidence interval: 1.06, 2.46) in the highest category. A monotonic but nonsignificant trend was observed with chronic B(a)P exposure and acute myocardial infarction (n = 184). When follow-up was restricted to active employment, the hazard ratio for IHD was 2.39 (95% confidence interval: 0.95, 6.05) in the highest cumulative B(a)P category. The stronger associations observed during employment suggest that risk may not persist after exposure cessation. No associations with recent or current exposure were observed. IHD was associated with chronic (but not current) PAH exposure in a high-exposure occupational setting. Given the widespread workplace exposure to PAHs and heart disease's high prevalence, even modest associations produce a high burden.

  9. Differences of acute versus chronic ethanol exposure on anxiety-like behavioral responses in zebrafish.

    Science.gov (United States)

    Mathur, Priya; Guo, Su

    2011-06-01

    Zebrafish, a vertebrate model organism amenable to high throughput screening, is an attractive system to model and study the mechanisms underlying human diseases. Alcoholism and alcoholic medical disorders are among the most debilitating diseases, yet the mechanisms by which ethanol inflicts the disease states are not well understood. In recent years zebrafish behavior assays have been used to study learning and memory, fear and anxiety, and social behavior. It is important to characterize the effects of ethanol on zebrafish behavioral repertoires in order to successfully harvest the strength of zebrafish for alcohol research. One prominent effect of alcohol in humans is its effect on anxiety, with acute intermediate doses relieving anxiety and withdrawal from chronic exposure increasing anxiety, both of which have significant contributions to alcohol dependence. In this study, we assess the effects of both acute and chronic ethanol exposure on anxiety-like behaviors in zebrafish, using two behavioral paradigms, the Novel Tank Diving Test and the Light/Dark Choice Assay. Acute ethanol exposure exerted significant dose-dependent anxiolytic effects. However, withdrawal from repeated intermittent ethanol exposure disabled recovery from heightened anxiety. These results demonstrate that zebrafish exhibit different anxiety-like behavioral responses to acute and chronic ethanol exposure, which are remarkably similar to these effects of alcohol in humans. Because of the accessibility of zebrafish to high throughput screening, our results suggest that genes and small molecules identified in zebrafish will be of relevance to understand how acute versus chronic alcohol exposure have opposing effects on the state of anxiety in humans. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Occupational exposure to particles and incidence of acute myocardial infarction and other ischaemic heart disease.

    Science.gov (United States)

    Wiebert, Pernilla; Lönn, Maria; Fremling, Karin; Feychting, Maria; Sjögren, Bengt; Nise, Gun; Kauppinen, T; Plato, Nils; Gustavsson, Per

    2012-09-01

    Ambient particulate air pollution has been linked to cardiovascular disease. Occupational particle exposure levels may be several times higher than ambient levels but has been less studied. The authors investigated the association between occupational exposure to particles and the incidence of ischaemic heart disease (IHD). The cohort included all manual workers in the Swedish national census of 1980 with information on demographic data and occupation. Information on hospital admissions for acute myocardial infarction or other IHDs and cause of death were obtained from nation-wide registers. A job-exposure matrix for exposure to small (1 μm) particles was developed. HRs were calculated with Cox regression with adjustment for sex, age, socioeconomic group and urban/rural residential area. Exposure to small particles was associated with an increased HR for acute myocardial infarction of 1.12 (95% CI 1.09 to 1.15), and HR for exposure to large particles was 1.14 (95% CI 1.10 to 1.18). The association was somewhat stronger for workers exposed to small particles for more than 5 years, 1.21 (95% CI 1.11 to 1.31), but no trend with exposure intensity was found. The risk associated with exposure to small particles was higher among women than among men, 1.30 (95% CI 1.12 to 1.51) and 1.10 (95% CI 1.07 to 1.14), respectively. Findings were essentially similar for other IHDs. This explorative study gives some support to the hypothesis that occupational exposure to particles increases the risk of acute myocardial infarction and other IHD. The findings must be interpreted cautiously due to lack of smoking data.

  11. Self-reported acute health symptoms and exposure to companion animals#

    Science.gov (United States)

    Self-reported acute health symptoms and exposure to companion animalsWhitney S. Krueger1,2, Elizabeth D. Hilborn2, Timothy J. Wade21Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA2Environmental Public Health Division, Office of Research and Development, U...

  12. ACUTE BEHAVORIAL EFFECTS FROM EXPOSURE TO TWO-STROKE ENGINE EXHAUST

    Science.gov (United States)

    Benefits of changing from two-stroke to four-stroke engines (and other remedial requirements) can be evaluated (monetized) from the standpoint of acute behavioral effects of human exposure to exhaust from these engines. The monetization process depends upon estimates of the magn...

  13. In Utero Exposure to Lipopolysaccharide Alters the Postnatal Acute Phase Response in Beef Heifers

    Science.gov (United States)

    This study was designed to determine the potential effect of prenatal lipopolysaccharide (LPS) exposure on the postnatal acute phase response (APR) to an LPS challenge in heifers. Pregnant crossbred cows (n = 50) were separated into prenatal immune stimulation (PIS; n = 25; administered 0.1 microgr...

  14. The effect of chronic ammonia exposure on acute phase proteins, immunoglobulin and cytokines in laying hens

    Science.gov (United States)

    Ammonia is a potential health hazard to both humans and animals, causing systemic low-grade inflammation based on its levels and durations. The objective of this study was to examine the effect of 45 weeks of exposure to 30 ppm NH3 on the concentrations of acute phase proteins, immunoglobulins and c...

  15. TOXICITY PATHWAY ANALYSIS IN AGING BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    Science.gov (United States)

    The influence of aging on susceptibility to environmental stressors is poorly understood. To investigate the contribution of different life stages on response to toxicants, we examined the effects of acute exposure by oral gavage of the volatile organic solvent toluene (0.00, 0.3...

  16. TOXICITY PATHWAY ANALYSIS IN AGING BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    Science.gov (United States)

    The influence of aging on susceptibility to environmental stressors is poorly understood. To investigate the contribution of different life stages on response to toxicants, we examined the effects of acute exposure by oral gavage of the volatile organic solvent toluene (0.00, 0.3...

  17. Striatal dopamine dynamics in mice following acute and repeated toluene exposure.

    Science.gov (United States)

    Apawu, Aaron K; Mathews, Tiffany A; Bowen, Scott E

    2015-01-01

    The abused inhalant toluene has potent behavioral effects, but only recently has progress been made in understanding the neurochemical actions that mediate the action of toluene in the brain. Available evidence suggests that toluene inhalation alters dopamine (DA) neurotransmission, but toluene's mechanism of action is unknown. The present study evaluated the effect of acute and repeated toluene inhalation (0, 2,000, or 4,000 ppm) on locomotor activity as well as striatal DA release and uptake using slice fast-scan cyclic voltammetry. Acutely, 2,000 and 4,000 ppm toluene increased locomotor activity, while neurochemically only 4,000 ppm toluene potentiated electrically evoked DA release across the caudate-putamen and the nucleus accumbens. Repeated administration of toluene resulted in sensitization to toluene's locomotor activity effects. Brain slices obtained from mice repeatedly exposed to toluene demonstrated no difference in stimulated DA release in the caudate-putamen as compared to control animals. Repeated exposure to 2,000 and 4,000 ppm toluene caused a concentration-dependent decrease of 25-50 % in evoked DA release in the nucleus accumbens core and shell relative to air-exposed mice. These voltammetric neurochemical findings following repeated toluene exposure suggest that there may be a compensatory downregulation of the DA system. Acute or repeated toluene exposure had no effect on the DA uptake kinetics. Taken together, these results demonstrate that acute toluene inhalation potentiates DA release, while repeated toluene exposure attenuates DA release in the nucleus accumbens only.

  18. Neurobehavorial effects of acute exposure to four solvents: meta-abalyses

    Science.gov (United States)

    Meta-and re-analyses of the available data for the neurobehavioral effects of acute inhalation exposure to toluene were reported by Benignus et al. (2007). The present study was designed to test the generality of the toluene results in as many other solvents as possible by furthe...

  19. Pathogenesis of Acute and Delayed Corneal Lesions after Ocular Exposure to Sulfur Mustard Vapor

    Science.gov (United States)

    2012-01-01

    had poor outcomes. Using a rabbit corneal vapor exposure model, we previously demonstrated a clinical progression with acute and chronic sequelae...can cause a permanent reduction in visual acuity or complete loss of eyesight [6]. The pathogenesis of MGK has been clinically described as a chronic

  20. Effects of maternal high-fat diet and sedentary lifestyle on susceptibility of adult offspring to ozone exposure in rats.

    Science.gov (United States)

    Gordon, C J; Phillips, P M; Johnstone, A F M; Schmid, J; Schladweiler, M C; Ledbetter, A; Snow, S J; Kodavanti, U P

    2017-05-01

    Epidemiological and experimental data suggest that obesity exacerbates the health effects of air pollutants such as ozone (O3). Maternal inactivity and calorically rich diets lead to offspring that show signs of obesity. Exacerbated O3 susceptibility of offspring could thus be manifested by maternal obesity. Thirty-day-old female Long-Evans rats were fed a control (CD) or high-fat (HF) (60% calories) diet for 6 wks and then bred. GD1 rats were then housed with a running wheel (RW) or without a wheel (SED) until parturition, creating four groups of offspring: CD-SED, CD-RW, HF-SED and HF-RW. HF diet was terminated at PND 35 and all offspring were placed on CD. Body weight and %fat of dams were greatest in order; HF-SED > HF-RW > CD-SED > CD-RW. Adult offspring were exposed to O3 for two consecutive days (0.8 ppm, 4 h/day). Glucose tolerance tests (GTT), ventilatory parameters (plethysmography), and bronchoalveolar fluid (BALF) cell counts and protein biomarkers were performed to assess response to O3. Exercise and diet altered body weight and %fat of young offspring. GTT, ventilation and BALF cell counts were exacerbated by O3 with responses markedly exacerbated in males. HF diet and O3 led to significant exacerbation of several BALF parameters: total cell count, neutrophils and lymphocytes were increased in male HF-SED versus CD-SED. Males were hyperglycemic after O3 exposure and exhibited exacerbated GTT responses. Ventilatory dysfunction was also exacerbated in males. Maternal exercise had minimal effects on O3 response. The results of this exploratory study suggest a link between maternal obesity and susceptibility to O3 in their adult offspring in a sex-specific manner.

  1. A Method for Quantifying the Acute Health Impacts of Residential Non-Biological Exposure Via Inhalation

    Energy Technology Data Exchange (ETDEWEB)

    Logue, Jennifer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sherman, Max H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Singer, Bret C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-08-01

    The inability to monetize the health costs of acute exposures in homes and the benefits of various control options is a barrier to justifying policies and approaches that can reduce exposure and improve health.We synthesized relationships between short-term outdoor concentration changes and health outcomes to estimate the health impacts of short-term in-home exposures. Damage and cost impacts of specific health outcomes were taken from the literature. We assessed the impact of vented and non-vented residential natural gas cooking burners on Southern California occupants for two pollutants (NO2 and CO).

  2. Acute phase proteins in cattle after exposure to complex stress

    DEFF Research Database (Denmark)

    Lomborg, S. R.; Nielsen, L. R.; Heegaard, Peter M. H.

    2008-01-01

    Abstract Stressors such as weaning, mixing and transportation have been shown to lead to increased blood concentrations of acute phase proteins (APP), including serum amyloid A (SAA) and haptoglobin, in calves. This study was therefore undertaken to assess whether SAA and haptoglobin levels...... in blood mirror stress in adult cattle. Six clinically healthy Holstein cows and two Holstein heifers were transported for four to six hours to a research facility, where each animal was housed in solitary tie stalls. Blood samples for evaluation of leukocyte counts and serum SAA and haptoglobin...... concentrations were obtained before (0-sample) and at 8, 24 and 48 hours after the start of transportation. Upon arrival the animals gave the impression of being anxious, and they appeared to have difficulty coping with isolation and with being tied on the slippery floors of the research stable. Serum...

  3. Prenatal and acute cocaine exposure affects neural responses and habituation to visual stimuli.

    Science.gov (United States)

    Riley, Elizabeth; Kopotiyenko, Konstantin; Zhdanova, Irina

    2015-01-01

    Psychostimulants have many effects on visual function, from adverse following acute and prenatal exposure to therapeutic on attention deficit. To determine the impact of prenatal and acute cocaine exposure on visual processing, we studied neuronal responses to visual stimuli in two brain regions of a transgenic larval zebrafish expressing the calcium indicator GCaMP-HS. We found that both red light (LF) and dark (DF) flashes elicited similar responses in the optic tectum neuropil (TOn), while the dorsal telencephalon (dTe) responded only to LF. Acute cocaine (0.5 μM) reduced neuronal responses to LF in both brain regions but did not affect responses to DF. Repeated stimulus presentation (RSP) led to habituation of dTe neurons to LF. Acute cocaine prevented habituation. TOn habituated to DF, but not LF, and DF habituation was not modified by cocaine. Remarkably, prenatal cocaine exposure (PCE) prevented the effects of acute cocaine on LF response amplitude and habituation later in development in both brain regions, but did not affect DF responses. We discovered that, in spite of similar neural responses to LF and DF in the TO (superior colliculus in mammals), responses to LF are more complex, involving dTe (homologous to the cerebral cortex), and are more vulnerable to cocaine. Our results demonstrate that acute cocaine exposure affects visual processing differentially by brain region, and that PCE modifies zebrafish visual processing in multiple structures in a stimulus-dependent manner. These findings are in accordance with the major role that the optic tectum and cerebral cortex play in sustaining visual attention, and support the hypothesis that modification of these areas by PCE may be responsible for visual deficits noted in humans. This model offers new methodological approaches for studying the adverse and therapeutic effects of psychostimulants on attention, and for the development of new pharmacological interventions.

  4. [Application of direct electric current and intravenous ozone therapy in the complex treatment of destructive forms of acute pancreatitis in experiment].

    Science.gov (United States)

    Zhakiev, B S; Zhumabaeva, A N; Kaliev, A A; Kazbekova, G A

    2013-01-01

    The results of experimental study which have carried out on 40 outbread dogs were analyzed in this thesis. Modeling of destructive pancreatitis in animals has been achieved via canalicular-hypertensive model by S.A. Shalimov. 4 series of experimental study were made to achieve the targeted goal. The first series 10 dogs without treatment, the second series 10 dogs in which conventional conservative therapy was used for the treatment of acute experimental destructive pancreatitis in animals, the third series 10 dogs that underwent intravenous ozone therapy in the complex together with medication therapy, the forth series the effectiveness of combined administration of intravenous ozone therapy and small doses of direct current in 10 dogs was evaluated. Combined administration of small doses of DC and intravenous ozone therapy in the complex treatment of destructive pancreatitis shows antiphlogistic action, favors accelerated rejection of necrotic tissue, remits inflammatory process as well as encourages regeneration process in pancreas whereby allows to decrease the mortality in experimental animals from 60% to 20%.

  5. Variability in Ozone-Induced Pulmonary Injury and Inflammation in Healthy and Cardiovascular Compromised Rat Models

    Science.gov (United States)

    The molecular bases for variability in air pollutant-induced pulmonary injury due to underlying cardiovascular (CVD) and/or metabolic diseases are unknown. We hypothesized that healthy and genetic CVD-prone rat models will exhibit exacerbated response to acute ozone exposure depe...

  6. Acute and Chronic Exposure to CO2 in Space Flight

    Science.gov (United States)

    Alexander, D.; Wu, J.; Barr, Y. R.; Watkins, S. D.

    2010-01-01

    Spacecraft and space stations, similar to other habitable confined spaces such as submarines, need to provide a breathable atmosphere for their inhabitants. The inevitable production of CO2 during respiration necessitates life support systems that "scrub" the atmosphere and lower CO2 levels. Due to operational limitations associated with space flight (limited mass, volume, power, and consumables) CO2 is not scrubbed down to its terrestrial equivalent of 0.03% CO2 (ppCO2 of 0.23 mmHg), but is kept below 0.7% (ppCO2 of 5.3 mmHg), a level established in NASA s 180-day mission Spacecraft Maximum Allowable Concentration (SMAC) to be safe and unlikely to cause symptoms. Reports of space flight crewmembers becoming symptomatic with headaches, fatigue, and malaise at levels below those known to cause such symptoms terrestrially has prompted studies measuring the levels of CO2 on both the space shuttle and the space station. Data from cabin atmosphere sampling were collected on space shuttle missions STS-113, STS-122, STS-123, and International Space Station Expeditions 12-15 and 17, and the measured CO2 levels were then correlated to symptoms reported by the crew. The results indicate that a correlation exists between CO2 levels and symptomatology, however causality cannot be established at this time. While the short-term effects of elevated CO2 exposure are well known terrestrially, less is known regarding potential long-term effects of prolonged exposure to a CO2-rich environment or how the physiological changes caused by microgravity may interact with such exposures. Other challenges include limitations in the CO2 monitors used, lack of convection in the microgravity environment, and formation of localized CO2 pockets. As it is unclear if the unique environment of space increases sensitivity to CO2 or if other confounding factors are present, further research is planned to elucidate these points. At the same time, efforts are underway to update the SMAC to a lower level

  7. Structural and functional changes of the human macula during acute exposure to high altitude.

    Directory of Open Access Journals (Sweden)

    M Dominik Fischer

    Full Text Available BACKGROUND: This study aimed to quantify structural and functional changes at the macula during acute exposure to high altitude and to assess their structure/function relationship. This work is related to the Tuebingen High Altitude Ophthalmology (THAO study. METHODOLOGY/PRINCIPAL FINDINGS: Spectral domain optical coherence tomography and microperimetry were used to quantify changes of central retinal structure and function in 14 healthy subjects during acute exposure to high altitude (4559 m. High-resolution volume scans and fundus-controlled microperimetry of the posterior pole were performed in addition to best-corrected visual acuity (BCVA measurements and assessment of acute mountain sickness. Analysis of measurements at altitude vs. baseline revealed increased total retinal thickness (TRT in all four outer ETDRS grid subfields during acute altitude exposure (TRT(outer = 2.80 ± 1.00 μm; mean change ± 95%CI. This change was inverted towards the inner four subfields (TRT(inner = -1.89 ± 0.97 μm with significant reduction of TRT in the fovea (TRT(foveal = -6.62 ± 0.90 μm at altitude. BCVA revealed no significant difference compared to baseline (0.06 ± 0.08 logMAR. Microperimetry showed stable mean sensitivity in all but the foveal subfield (MS(foveal = -1.12 ± 0.68 dB. At baseline recordings before and >2 weeks after high altitude exposure, all subjects showed equal levels with no sign of persisting structural or functional sequels. CONCLUSIONS/SIGNIFICANCE: During acute exposure to high altitude central retinal thickness is subject to minor, yet statistically significant changes. These alterations describe a function of eccentricity with an increase in regions with relatively higher retinal nerve fiber content and vascular arcades. However, these changes did not correlate with measures of central retinal function or acute mountain sickness. For the first time a quantitative approach has been used to assess these changes during acute

  8. Structural and Functional Changes of the Human Macula during Acute Exposure to High Altitude

    Science.gov (United States)

    Fischer, M. Dominik; Willmann, Gabriel; Schatz, Andreas; Schommer, Kai; Zhour, Ahmad; Zrenner, Eberhart; Bartz-Schmidt, Karl U.; Gekeler, Florian

    2012-01-01

    Background This study aimed to quantify structural and functional changes at the macula during acute exposure to high altitude and to assess their structure/function relationship. This work is related to the Tuebingen High Altitude Ophthalmology (THAO) study. Methodology/Principal Findings Spectral domain optical coherence tomography and microperimetry were used to quantify changes of central retinal structure and function in 14 healthy subjects during acute exposure to high altitude (4559 m). High-resolution volume scans and fundus-controlled microperimetry of the posterior pole were performed in addition to best-corrected visual acuity (BCVA) measurements and assessment of acute mountain sickness. Analysis of measurements at altitude vs. baseline revealed increased total retinal thickness (TRT) in all four outer ETDRS grid subfields during acute altitude exposure (TRTouter = 2.80±1.00 μm; mean change±95%CI). This change was inverted towards the inner four subfields (TRTinner = −1.89±0.97 μm) with significant reduction of TRT in the fovea (TRTfoveal = −6.62±0.90 μm) at altitude. BCVA revealed no significant difference compared to baseline (0.06±0.08 logMAR). Microperimetry showed stable mean sensitivity in all but the foveal subfield (MSfoveal = −1.12±0.68 dB). At baseline recordings before and >2 weeks after high altitude exposure, all subjects showed equal levels with no sign of persisting structural or functional sequels. Conclusions/Significance During acute exposure to high altitude central retinal thickness is subject to minor, yet statistically significant changes. These alterations describe a function of eccentricity with an increase in regions with relatively higher retinal nerve fiber content and vascular arcades. However, these changes did not correlate with measures of central retinal function or acute mountain sickness. For the first time a quantitative approach has been used to assess these changes during acute, non

  9. Ceftriaxone attenuates locomotor activity induced by acute and repeated cocaine exposure in mice.

    Science.gov (United States)

    Tallarida, Christopher S; Corley, Gladys; Kovalevich, Jane; Yen, William; Langford, Dianne; Rawls, Scott M

    2013-11-27

    Ceftriaxone (CTX) decreases locomotor activation produced by initial cocaine exposure and attenuates development of behavioral sensitization produced by repeated cocaine exposure. An important question that has not yet been answered is whether or not CTX reduces behavioral sensitization to cocaine in cases in which the antibiotic is administered only during the period of cocaine absence that follows repeated cocaine exposure and precedes reintroduction to cocaine. We investigated this question using C57BL/6 mice. Mice pretreated with cocaine (15mg/kg×14 days) and then challenged with cocaine (15mg/kg) after 30 days of cocaine absence displayed sensitization of locomotor activity. For combination experiments, CTX injected during the 30 days of cocaine absence attenuated behavioral sensitization produced by cocaine challenge. In the case in which CTX was injected together with cocaine for 14 days, development of behavioral sensitization to cocaine challenge was also reduced. CTX attenuated the increase in locomotor activity produced by acute cocaine exposure; however, its efficacy was dependent on the dose of cocaine as inhibition was detected against 30mg/kg, but not 15mg/kg, of cocaine. These results from mice indicate that CTX attenuates locomotor activity produced by acute and repeated cocaine exposure and counters cocaine's locomotor activating properties in a paradigm in which the antibiotic is injected during the period of forced cocaine absence that follows repeated cocaine exposure.

  10. Factors affecting the estimated probabilistic acute dietary exposure to captan from apple consumption.

    Science.gov (United States)

    Zentai, A; Sali, J; Szabó, I J; Szeitzné-Szabó, M; Ambrus, A; Vásárhelyi, A

    2013-01-01

    The effect of the number of pesticide residue values below the LOQ/LOD of analytical methods, the variability of residues in individual fruits, mass of fruit units and the number of bootstrap iterations was studied on the probabilistically estimated acute exposure of consumers. The 4720 daily apple consumption data and the results of 1239 apple sample analyses for captan residues, performed within the Hungarian monitoring programme between 2005 and 2011, were used in this study as model matrix. Up to about 95th percentile exposure (µg/(kg bw·day)), simply multiplying each residue in composite samples with each consumption value gave similar estimates to those obtained with the complex procedure taking also into account the mass of and residues in individual fruits. However, the exposure above the 95th percentile calculated with the complex procedure gradually increased with increasing percentile level compared to the simple procedure. Including the high number of non-detects reduced the estimated exposure, which was the highest when only the residues measured in treated fruits were taken into account. The number of bootstrap iterations between 100 and 10,000 did not significantly affect the calculated exposure. The 99.99th percentile exposure amounted to 17.9% of the acute reference dose of 300 µg/(kg bw·day) for women of childbearing age.

  11. Acute phase response, inflammation and metabolic syndrome biomarkers of Libby asbestos exposure

    Energy Technology Data Exchange (ETDEWEB)

    Shannahan, Jonathan H. [Curriculum in Toxicology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599 (United States); Alzate, Oscar [Systems Proteomics Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599 (United States); Winnik, Witold M.; Andrews, Debora [Proteomics Core, Research Core Unit, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Schladweiler, Mette C. [Cardiopulmonary and Immunotoxicology Branch, Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Ghio, Andrew J. [Clinical Research Branch, Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Chapel Hill, NC 27599 (United States); Gavett, Stephen H. [Cardiopulmonary and Immunotoxicology Branch, Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Kodavanti, Urmila P., E-mail: Kodavanti.Urmila@epa.gov [Cardiopulmonary and Immunotoxicology Branch, Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States)

    2012-04-15

    Identification of biomarkers assists in the diagnosis of disease and the assessment of health risks from environmental exposures. We hypothesized that rats exposed to Libby amphibole (LA) would present with a unique serum proteomic profile which could help elucidate epidemiologically-relevant biomarkers. In four experiments spanning varied protocols and temporality, healthy (Wistar Kyoto, WKY; and F344) and cardiovascular compromised (CVD) rat models (spontaneously hypertensive, SH; and SH heart failure, SHHF) were intratracheally instilled with saline (control) or LA. Serum biomarkers of cancer, inflammation, metabolic syndrome (MetS), and the acute phase response (APR) were analyzed. All rat strains exhibited acute increases in α-2-macroglobulin, and α1-acid glycoprotein. Among markers of inflammation, lipocalin-2 was induced in WKY, SH and SHHF and osteopontin only in WKY after LA exposure. While rat strain- and age-related changes were apparent in MetS biomarkers, no LA effects were evident. The cancer marker mesothelin was increased only slightly at 1 month in WKY in one of the studies. Quantitative Intact Proteomic profiling of WKY serum at 1 day or 4 weeks after 4 weekly LA instillations indicated no oxidative protein modifications, however APR proteins were significantly increased. Those included serine protease inhibitor, apolipoprotein E, α-2-HS-glycoprotein, t-kininogen 1 and 2, ceruloplasmin, vitamin D binding protein, serum amyloid P, and more 1 day after last LA exposure. All changes were reversible after a short recovery regardless of the acute or long-term exposures. Thus, LA exposure induces an APR and systemic inflammatory biomarkers that could have implications in systemic and pulmonary disease in individuals exposed to LA. -- Highlights: ► Biomarkers of asbestos exposure are required for disease diagnosis. ► Libby amphibole exposure is associated with increased human mortality. ► Libby amphibole increases circulating proteins involved

  12. Limited inflammatory response in rats after acute exposure to a silicon carbide nanoaerosol

    Science.gov (United States)

    Laloy, J.; Lozano, O.; Alpan, L.; Masereel, B.; Toussaint, O.; Dogné, J. M.; Lucas, S.

    2015-08-01

    Inhalation represents the major route of human exposure to manufactured nanomaterials (NMs). Assessments are needed about the potential risks of NMs from inhalation on different tissues and organs, especially the respiratory tract. The aim of this limited study is to determine the potential acute pulmonary toxicity in rats exposed to a dry nanoaerosol of silicon carbide (SiC) nanoparticles (NPs) in a whole-body exposure (WBE) model. The SiC nanoaerosol is composed of a bimodal size distribution of 92.8 and 480 nm. The exposure concentration was 4.91 mg/L, close to the highest recommended concentration of 5 mg/L by the Organisation for Economic Co-operation and Development. Rats were exposed for 6 h to a stable and reproducible SiC nanoaerosol under real-time measurement conditions. A control group was exposed to the filtered air used to create the nanoaerosol. Animals were sacrificed immediately, 24 or 72 h after exposure. The bronchoalveolar lavage fluid from rat lungs was recovered. Macrophages filled with SiC NPs were observed in the rat lungs. The greatest load of SiC and macrophages filled with SiC were observed on the rat lungs sacrificed 24 h after acute exposure. A limited acute inflammatory response was found up to 24 h after exposure characterized by a lactate dehydrogenase and total protein increase or presence of inflammatory cells in pulmonary lavage. For this study a WBE model has been developed, it allows the simultaneous exposure of six rats to a nanoaerosol and six rats to clean-filtered air. The nanoaerosol was generated using a rotating brush system (RBG-1000) and analyzed with an electrical low pressure impactor in real time.

  13. Limited inflammatory response in rats after acute exposure to a silicon carbide nanoaerosol

    Energy Technology Data Exchange (ETDEWEB)

    Laloy, J., E-mail: julie.laloy@unamur.be [University of Namur (UNamur), Department of Pharmacy, Namur Nanosafety Centre (NNC), Namur Research Institute for Life Sciences NARILIS (Belgium); Lozano, O. [University of Namur (UNamur), Research Centre in Physics of Matter and Radiation (PMR), Namur Nanosafety Centre NNC, Namur Research Institute for Life Sciences NARILIS (Belgium); Alpan, L.; Masereel, B. [University of Namur (UNamur), Department of Pharmacy, Namur Nanosafety Centre (NNC), Namur Research Institute for Life Sciences NARILIS (Belgium); Toussaint, O. [University of Namur (UNamur), Laboratory of Cellular Biochemistry and Biology (URBC), Namur Nanosafety Centre NNC, Namur Research Institute for Life Sciences NARILIS (Belgium); Dogné, J. M. [University of Namur (UNamur), Department of Pharmacy, Namur Nanosafety Centre (NNC), Namur Research Institute for Life Sciences NARILIS (Belgium); Lucas, S. [University of Namur (UNamur), Research Centre in Physics of Matter and Radiation (PMR), Namur Nanosafety Centre NNC, Namur Research Institute for Life Sciences NARILIS (Belgium)

    2015-08-15

    Inhalation represents the major route of human exposure to manufactured nanomaterials (NMs). Assessments are needed about the potential risks of NMs from inhalation on different tissues and organs, especially the respiratory tract. The aim of this limited study is to determine the potential acute pulmonary toxicity in rats exposed to a dry nanoaerosol of silicon carbide (SiC) nanoparticles (NPs) in a whole-body exposure (WBE) model. The SiC nanoaerosol is composed of a bimodal size distribution of 92.8 and 480 nm. The exposure concentration was 4.91 mg/L, close to the highest recommended concentration of 5 mg/L by the Organisation for Economic Co-operation and Development. Rats were exposed for 6 h to a stable and reproducible SiC nanoaerosol under real-time measurement conditions. A control group was exposed to the filtered air used to create the nanoaerosol. Animals were sacrificed immediately, 24 or 72 h after exposure. The bronchoalveolar lavage fluid from rat lungs was recovered. Macrophages filled with SiC NPs were observed in the rat lungs. The greatest load of SiC and macrophages filled with SiC were observed on the rat lungs sacrificed 24 h after acute exposure. A limited acute inflammatory response was found up to 24 h after exposure characterized by a lactate dehydrogenase and total protein increase or presence of inflammatory cells in pulmonary lavage. For this study a WBE model has been developed, it allows the simultaneous exposure of six rats to a nanoaerosol and six rats to clean-filtered air. The nanoaerosol was generated using a rotating brush system (RBG-1000) and analyzed with an electrical low pressure impactor in real time.

  14. Cancer Events After Acute or Chronic Exposure to Sulfur Mustard: A Review of the Literature

    Science.gov (United States)

    Razavi, Seyed Mansour; Abdollahi, Mohammad; Salamati, Payman

    2016-01-01

    Background: Sulfur mustard (SM) has been considered as a carcinogen in the laboratory studies. However, its carcinogenic effects on human beings were not well discussed. The main purpose of our study is to assess carcinogenesis of SM following acute and/or chronic exposures in human beings. Methods: The valid scientific English and Persian databases including PubMed, Web of Science, Scopus, IranMedex, and Irandoc were searched and the collected papers reviewed. The used keywords were in two languages: English and Persian. The inclusion criteria were the published original articles indexed in above-mentioned databases. Eleven full-texts out of 296 articles were found relevant and then assessed. Results: Studies on the workers of the SM factories during the World Wars showed that the long-term chronic exposure to mustards can cause a variety of cancers in the organs such as oral cavity, larynx, lung, and skin. Respiratory system was the most important affected system. Acute single exposure to SM was assumed as the carcinogenic inducer in the lung and blood and for few cancers including basal cell carcinoma and squamous cell carcinoma. Conclusions: SM is a proven carcinogen in chronic situations although data are not enough to strongly conclude in acute exposure. PMID:27280012

  15. Effects of Acute Exposures to Carbon Dioxide Upon Cognitive Functions

    Science.gov (United States)

    Scully, R. R.; Alexander, D. J.; Ryder, V. E.; Lam, C. W.; Statish, U.; Basner, M.

    2016-01-01

    Large quantities of carbon dioxide (CO2) originate from human metabolism and typically, within spacecraft, remain about 10-fold higher in concentration than at the earth's surface. There have been recurring complaints by crew members of episodes of "mental viscosity" adversely affecting their performance, and there is evidence from the International Space Station (ISS) that associates CO2 levels with reports of headaches by crewmembers. Additionally, there is concern that CO2 may contribute to vision impairment and intracranial pressure that has been observed in some crewmembers. Consequently, flight rules have been employed to control the level of CO2 below 4 mm Hg, which is well below the existing Spacecraft Maximum Allowable Concentration (SMAC) of 10 mm Hg for 24-hour exposures, and 5.3 mm Hg for exposures of 7 to 180 days. However, the flight rule imposed limit, which places additional demands upon resources and current technology, still exceeds the lower bound of the threshold range for reportable headaches (2 - 5 mm Hg). Headaches, while sometime debilitating themselves, are also symptoms that can provide evidence that physiological defense mechanisms have been breached. The causes of the headaches may elicit other subtle adverse effects that occur at CO2 levels well below that for headaches. The concern that CO2 may have effects at levels below the threshold for headaches appears to be substantiated in unexpected findings that CO2 at concentrations below 2 mm Hg substantially reduced some cognitive functions that are associated with the ability to make complex decisions in conditions that are characterized by volatility, uncertainty, complexity, ambiguity, and delayed feedback. These are conditions that could be encountered by crews in off-nominal situations or during the first missions beyond low earth orbit. If findings of the earlier study are confirmed in crew-like subjects, our findings would provide additional evidence that CO2 may need to be

  16. Investigating the synchronization of hippocampal neural network in response to acute nicotine exposure

    Directory of Open Access Journals (Sweden)

    Akay Metin

    2010-07-01

    Full Text Available Abstract Previous studies suggested that γ oscillations in the brain are associated with higher order cognitive function including selective visual attention, motor task planning, sensory perception, working memory and dreaming REM sleep. These oscillations are mainly observed in cortical regions and also occur in neocortical and subcortical areas and the hippocampus. In this paper, we investigate the influence of acute exposure to nicotine on the complexity of hippocampal γ oscillations. Using the approximate entropy method, the influence of acute nicotine exposure on the hippocampal γ oscillations was investigated. The hippocampal γ oscillations have been generated in response to the 100 Hz stimulus and isolated using the visual inspection and spectral analysis method. Our central hypothesis is that acute exposure to nicotine significantly reduces the complexity of hippocampal γ oscillations. We used brain-slice recordings and the approximate entropy method to test this hypothesis. The approximate entropy (complexity values of the hippocampal γ oscillations are estimated from the 14 hippocampal slices. Our results show that it takes at least 100 msec to see any hippocampal activities in response to the 100 Hz stimulus. These patterns noticeably changed after 100 msec until 300 msec after the stimulus Finally, they were less prominent after 300 msec. We have analyzed the isolated hippocampal γ oscillations (between 150 and 250 msec after the stimulus using the approximate entropy (ApEn method. Our results showed that the ApEn (complexity values of hippocampal γ oscillations during nicotine exposure were reduced compared to those of hippocampal γ oscillations during control, and washout. This reduction was much more significant in response to acute nicotine exposure (p

  17. Effects of ozone inhalation during exercise in selected patients with heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Superko, H.R.; Adams, W.C.; Daly, P.W.

    1984-09-01

    In the present investigation, six male volunteers, ages 46 to 64 years, with clinically documented coronary heart disease and a well-defined symptomatic angina pectoris threshold, served as subjects. Each patient was exposed on three 40-minute occasions to either filtered air or ozone at concentrations of 0.20 or 0.30 parts per million (ppm), while walking on a treadmill at workloads simulating their regularly prescribed exercise training regimen. Results of standard pulmonary function tests and periodic observations of exercise ventilation, respiratory metabolism, electrocardiographic changes, hemodynamic response, and clinical signs and symptoms were recorded. Analysis of variance revealed that none of the patients physiologic responses to ozone exposure were statistically significant. Furthermore, neither onset of angina pain or ischemic changes were related to ozone exposure in a dose-dependent fashion. Patients evidenced no significant pulmonary function impairment or exercise ventilatory pattern alteration, as has been observed in clinically normal subjects exercising at similar ozone concentration levels. This apparent incongruity may be due to the fact that acute ozone toxicity is more closely related to the total amount of ozone inhaled, which is a function of pulmonary ventilation volume and exposure time, as well as ozone concentration. In the patients with angina, symptom-limited exercise tolerance resulted in a lower total amount of ozone inhaled than that observed to effect ozone toxicity in clinically normal subjects who exercised at greater intensities and for longer durations. Patients with angina appear to be no more susceptible to ozone toxicity than are clinically normal subjects at the effective doses imposed. However, had the patients exercised longer, they might well have evidenced pulmonary function impairment and/or cardiovascular strain. Hence, caution is advised in generalizing these observations to other conditions and patient groups.

  18. Growth at elevated ozone or elevated carbon dioxide concentration alters antioxidant capacity and response to acute oxidative stress in soybean (Glycine max)

    Energy Technology Data Exchange (ETDEWEB)

    Gillespie, K.M.; Rogers, A.; Ainsworth, E. A.

    2011-01-31

    Soybeans (Glycine max Merr.) were grown at elevated carbon dioxide concentration ([CO{sub 2}]) or chronic elevated ozone concentration ([O{sub 3}]; 90 ppb), and then exposed to an acute O{sub 3} stress (200 ppb for 4 h) in order to test the hypothesis that the atmospheric environment alters the total antioxidant capacity of plants, and their capacity to respond to an acute oxidative stress. Total antioxidant metabolism, antioxidant enzyme activity, and antioxidant transcript abundance were characterized before, immediately after, and during recovery from the acute O{sub 3} treatment. Growth at chronic elevated [O{sub 3}] increased the total antioxidant capacity of plants, while growth at elevated [CO{sub 2}] decreased the total antioxidant capacity. Changes in total antioxidant capacity were matched by changes in ascorbate content, but not phenolic content. The growth environment significantly altered the pattern of antioxidant transcript and enzyme response to the acute O{sub 3} stress. Following the acute oxidative stress, there was an immediate transcriptional reprogramming that allowed for maintained or increased antioxidant enzyme activities in plants grown at elevated [O{sub 3}]. Growth at elevated [CO{sub 2}] appeared to increase the response of antioxidant enzymes to acute oxidative stress, but dampened and delayed the transcriptional response. These results provide evidence that the growth environment alters the antioxidant system, the immediate response to an acute oxidative stress, and the timing over which plants return to initial antioxidant levels. The results also indicate that future elevated [CO{sub 2}] and [O{sub 3}] will differentially affect the antioxidant system.

  19. Comparative evaluation of effects of ozonated and chlorinated thermal discharges on estuarine and fresh water organisms. First quarterly progress report, April 1979

    Energy Technology Data Exchange (ETDEWEB)

    Guerra, C.R.; DelMonaco, J.L.; Singletary, J.H.; Sugam, R.J.; Meldrim, J.W.; Holmstrom, E.R.; Balog, G.F.

    1979-01-01

    The biological evaluation program incorporates three types of experimental tests: acute (96 hour) toxicity studies; behavioral (avoidance) response studies; and physiological (cough) response studies. In addition, specimens used in testing are examined for physical damage resulting from exposure to chlorine or ozoen. The objective of the acute (96 hour) toxicity study is to determine the respective lethal levels (LC/sub 50/) of chlorinated and ozonated waters. The objective of the behavioral (avoidance) response study is to determine what (if any) concentrations of ozone and of chlorine will be avoided. The objective of physiological (cough) response study is to determine what concentrations of ozone and of chlorine are physiologically detected. Ozonated and chlorinated waters were evaluated in all studies for both the addition of increased temperature and without it. Results indicate that ozone is less toxic than chlorine under the test conditions used. The lethal levels vary according to species of water quality measurements at Bergen Generating Station, New York are tabulated. (JBG)

  20. 20-HETE mediates ozone-induced, neutrophil-independent airway hyper-responsiveness in mice.

    Directory of Open Access Journals (Sweden)

    Philip R Cooper

    Full Text Available BACKGROUND: Ozone, a pollutant known to induce airway hyper-responsiveness (AHR, increases morbidity and mortality in patients with obstructive airway diseases and asthma. We postulate oxidized lipids mediate in vivo ozone-induced AHR in murine airways. METHODOLOGY/PRINCIPAL FINDINGS: Male BALB/c mice were exposed to ozone (3 or 6 ppm or filtered air (controls for 2 h. Precision cut lung slices (PCLS; 250 microm thickness containing an intrapulmonary airway ( approximately 0.01 mm(2 lumen area were prepared immediately after exposure or 16 h later. After 24 h, airways were contracted to carbachol (CCh. Log EC(50 and E(max values were then calculated by measuring the airway lumen area with respect to baseline. In parallel studies, dexamethasone (2.5 mg/kg, or 1-aminobenzotriazol (ABT (50 mg/kg were given intraperitoneal injection to naïve mice 18 h prior to ozone exposure. Indomethacin (10 mg/kg was administered 2 h prior. Cell counts, cytokine levels and liquid chromatography-mass spectrometry (LC-MS for lipid analysis were assessed in bronchoalveolar lavage (BAL fluid from ozone exposed and control mice. Ozone acutely induced AHR to CCh. Dexamethasone or indomethacin had little effect on the ozone-induced AHR; while, ABT, a cytochrome P450 inhibitor, markedly attenuated airway sensitivity. BAL fluid from ozone exposed animals, which did not contain an increase in neutrophils or interleukin (IL-6 levels, increased airway sensitivity following in vitro incubation with a naïve PCLS. In parallel, significant increases in oxidized lipids were also identified using LC-MS with increases of 20-HETE that were decreased following ABT treatment. CONCLUSIONS/SIGNIFICANCE: These data show that ozone acutely induces AHR to CCh independent of inflammation and is insensitive to steroid treatment or cyclooxygenase (COX inhibition. BAL fluid from ozone exposed mice mimicked the effects of in vivo ozone exposure that were associated with marked increases in

  1. Role of neutrophilic inflammation in ozone-induced epithelial alterations in the nasal airways of rats

    Science.gov (United States)

    Cho, Hye Youn

    Ozone is a principal oxidant air pollutant in photochemical smog. Epithelial cells lining the centriacinar region of lung and the proximal aspects of nasal passage are primary target sites for ozone-induced injury in laboratory animals. Acute exposure of rats to high ambient concentrations of ozone (e.g., 0.5 ppm) results in neutrophilic inflammation, epithelial hyperplasia and mucous cell metaplasia (MCM) in the nasal transitional epithelium (NTE) lining the proximal nasal airways. The principal purpose of the present study was to investigate the role of pre-metaplastic cellular responses, especially neutrophilic inflammation, in the pathogenesis of ozone-induced MCM in rat NTE. For this purpose, three specific hypotheses-based whole-animal inhalation studies were conducted. Male F344/N rats were exposed in whole-body inhalation chambers to 0 (filtered air) or 0.5 ppm ozone for 1-3 days (8 h/day). Histochemical, immunochemical, molecular and morphometric techniques were used to investigate the ozone-induced cellular and molecular events in the NTE. Two in vitro studies were also conducted to examine the effects of ozone-inducible cytokines (i.e., tumor necrosis factor-alpha; TNF- a, and interleukin-6; IL-6) on mucin gene (rMuc-5AC) expression. Ozone induced a rapid increase of rMuc-5AC mRNA in nasal tissues within hours after the start of exposure. It preceded the appearance of MCM, and persisted with MCM. Ozone-induced neutrophilic inflammation accompanied the mucin gene upregulation, but was resolved when MCM first appeared in the NTE. Antibody-mediated depletion of circulating neutrophils attenuated ozone-induced MCM, although it did not affect the ozone-induced epithelial hyperplasia and mucin mRNA upregulation. In another study, it was found that preexisting neutrophilic rhinitis induced by endotoxin augmented the ozone-induced MCM. However, pre-existing rhinitis did not alter the severity of ozone-induced epithelial hyperplasia and mucin gene upregulation

  2. Acute Respiratory Failure due to Alveolar Hemorrhage after Exposure to Organic Dust

    Directory of Open Access Journals (Sweden)

    Sun Mi Choi

    2016-05-01

    Full Text Available Diffuse alveolar hemorrhage (DAH is associated with severe outcomes. We report a case of acute respiratory failure that required mechanical ventilation and was clinically and pathologically diagnosed as DAH related to exposure to organic dust. A 39-year-old man, who had visited a warehouse to grade beans for purchase, was referred to our hospital for impending respiratory failure. His initial radiographic examinations revealed diffuse bilateral ground-glass opacities in his lungs and bronchoalveolar lavage resulted in progressively bloodier returns, which is characteristic of DAH. He underwent bedside open lung biopsy of his right lower lobe in the intensive care unit. Biopsy results revealed DAH and organization with accumulation of hemosiderin-laden macrophages and a few fibroblastic foci. The patient was treated with empirical antibiotics and high-dose corticosteroids and successfully weaned from mechanical ventilation. DAH might be considered in the differential diagnosis of patients with acute respiratory failure after exposure to organic particles.

  3. 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.

  4. Acute and chronic toxicity of sodium sulfate to four freshwater organisms in water-only exposures.

    Science.gov (United States)

    Wang, Ning; Dorman, Rebecca A; Ingersoll, Christopher G; Hardesty, Doug K; Brumbaugh, William G; Hammer, Edward J; Bauer, Candice R; Mount, David R

    2016-01-01

    The acute and chronic toxicity of sulfate (tested as sodium sulfate) was determined in diluted well water (hardness of 100 mg/L and pH 8.2) with a cladoceran (Ceriodaphnia dubia; 2-d and 7-d exposures), a midge (Chironomus dilutus; 4-d and 41-d exposures), a unionid mussel (pink mucket, Lampsilis abrupta; 4-d and 28-d exposures), and a fish (fathead minnow, Pimephales promelas; 4-d and 34-d exposures). Among the 4 species, the cladoceran and mussel were acutely more sensitive to sulfate than the midge and fathead minnow, whereas the fathead minnow was chronically more sensitive than the other 3 species. Acute-to-chronic ratios ranged from 2.34 to 5.68 for the 3 invertebrates but were as high as 12.69 for the fish. The fathead minnow was highly sensitive to sulfate during the transitional period from embryo development to hatching in the diluted well water, and thus, additional short-term (7- to 14-d) sulfate toxicity tests were conducted starting with embryonic fathead minnow in test waters with different ionic compositions at a water hardness of 100 mg/L. Increasing chloride in test water from 10 mg Cl/L to 25 mg Cl/L did not influence sulfate toxicity to the fish, whereas increasing potassium in test water from 1 mg K/L to 3 mg K/L substantially reduced the toxicity of sulfate. The results indicate that both acute and chronic sulfate toxicity data, and the influence of potassium on sulfate toxicity to fish embryos, need to be considered when environmental guidance values for sulfate are developed or refined.

  5. Exposure to acute stress enhances decision-making competence: Evidence for the role of DHEA.

    Science.gov (United States)

    Shields, Grant S; Lam, Jovian C W; Trainor, Brian C; Yonelinas, Andrew P

    2016-05-01

    Exposure to acute stress can impact performance on numerous cognitive abilities, but little is known about how acute stress affects real-world decision-making ability. In the present study, we induced acute stress with a standard laboratory task involving uncontrollable socio-evaluative stress and subsequently assessed decision-making ability using the Adult Decision Making Competence index. In addition, we took baseline and post-test saliva samples from participants to examine associations between decision-making competence and adrenal hormones. Participants in the stress induction group showed enhanced decision-making competence, relative to controls. Further, although both cortisol and dehydroepiandrosterone (DHEA) reactivity predicted decision-making competence when considered in isolation, DHEA was a significantly better predictor than cortisol when both hormones were considered simultaneously. Thus, our results show that exposure to acute stress can have beneficial effects on the cognitive ability underpinning real-world decision-making and that this effect relates to DHEA reactivity more than cortisol.

  6. 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.

  7. Disrupted Nitric Oxide Metabolism from Type II Diabetes and Acute Exposure to Particulate Air Pollution.

    Directory of Open Access Journals (Sweden)

    Ashley P Pettit

    Full Text Available Type II diabetes is an established cause of vascular impairment. Particulate air pollution is known to exacerbate cardiovascular and respiratory conditions, particularly in susceptible populations. This study set out to determine the impact of exposure to traffic pollution, with and without particle filtration, on vascular endothelial function in Type II diabetes. Endothelial production of nitric oxide (NO has previously been linked to vascular health. Reactive hyperemia induces a significant increase in plasma nitrite, the proximal metabolite of NO, in healthy subjects, while diabetics have a lower and more variable level of response. Twenty type II diabetics and 20 controls (ages 46-70 years were taken on a 1.5 hr roadway traffic air pollution exposure as passengers. We analyzed plasma nitrite, as a measure of vascular function, using forearm ischemia to elicit a reactive hyperemic response before and after exposure to one ride with and one without filtration of the particle components of pollution. Control subjects displayed a significant increase in plasma nitrite levels during reactive hyperemia. This response was no longer present following exposure to traffic air pollution, but did not vary with whether or not the particle phase was filtered out. Diabetics did not display an increase in nitrite levels following reactive hyperemia. This response was not altered following pollution exposure. These data suggest that components of acute traffic pollution exposure diminish vascular reactivity in non-diabetic individuals. It also confirms that type II diabetics have a preexisting diminished ability to appropriately respond to a vascular challenge, and that traffic pollution exposure does not cause a further measureable acute change in plasma nitrite levels in Type II diabetics.

  8. Acute lead exposure increases arterial pressure: role of the renin-angiotensin system.

    Directory of Open Access Journals (Sweden)

    Maylla Ronacher Simões

    Full Text Available BACKGROUND: Chronic lead exposure causes hypertension and cardiovascular disease. Our purpose was to evaluate the effects of acute exposure to lead on arterial pressure and elucidate the early mechanisms involved in the development of lead-induced hypertension. METHODOLOGY/PRINCIPAL FINDINGS: Wistar rats were treated with lead acetate (i.v. bolus dose of 320 µg/Kg, and systolic arterial pressure, diastolic arterial pressure and heart rate were measured during 120 min. An increase in arterial pressure was found, and potential roles of the renin-angiotensin system, Na(+,K(+-ATPase and the autonomic reflexes in this change in the increase of arterial pressure found were evaluated. In anesthetized rats, lead exposure: 1 produced blood lead levels of 37±1.7 µg/dL, which is below the reference blood concentration (60 µg/dL; 2 increased systolic arterial pressure (Ct: 109±3 mmHg vs Pb: 120±4 mmHg; 3 increased ACE activity (27% compared to Ct and Na(+,K(+-ATPase activity (125% compared to Ct; and 4 did not change the protein expression of the α1-subunit of Na(+,K(+-ATPase, AT(1 and AT(2. Pre-treatment with an AT(1 receptor blocker (losartan, 10 mg/Kg or an ACE inhibitor (enalapril, 5 mg/Kg blocked the lead-induced increase of arterial pressure. However, a ganglionic blockade (hexamethonium, 20 mg/Kg did not prevent lead's hypertensive effect. CONCLUSION: Acute exposure to lead below the reference blood concentration increases systolic arterial pressure by increasing angiotensin II levels due to ACE activation. These findings offer further evidence that acute exposure to lead can trigger early mechanisms of hypertension development and might be an environmental risk factor for cardiovascular disease.

  9. N-fixation in legumes--An assessment of the potential threat posed by ozone pollution.

    Science.gov (United States)

    Hewitt, D K L; Mills, G; Hayes, F; Norris, D; Coyle, M; Wilkinson, S; Davies, W

    2016-01-01

    The growth, development and functioning of legumes are often significantly affected by exposure to tropospheric ozone (O3) pollution. However, surprisingly little is known about how leguminous Nitrogen (N) fixation responds to ozone, with a scarcity of studies addressing this question in detail. In the last decade, ozone impacts on N-fixation in soybean, cowpea, mung bean, peanut and clover have been shown for concentrations which are now commonly recorded in ambient air or are likely to occur in the near future. We provide a synthesis of the existing literature addressing this issue, and also explore the effects that may occur on an agroecosystem scale by predicting reductions in Trifolium (clovers) root nodule biomass in United Kingdom (UK) pasture based on ozone concentration data for a "high" (2006) and "average" ozone year (2008). Median 8% and 5% reductions in clover root nodule biomass in pasture across the UK were predicted for 2006 and 2008 respectively. Seasonal exposure to elevated ozone, or short-term acute concentrations >100 ppb, are sufficient to reduce N-fixation and/or impact nodulation, in a range of globally-important legumes. However, an increasing global burden of CO2, the use of artificial fertiliser, and reactive N-pollution may partially mitigate impacts of ozone on N-fixation.

  10. Acute and chronic ethanol exposure differentially alters alcohol dehydrogenase and aldehyde dehydrogenase activity in the zebrafish liver.

    Science.gov (United States)

    Tran, Steven; Nowicki, Magda; Chatterjee, Diptendu; Gerlai, Robert

    2015-01-02

    Chronic ethanol exposure paradigms have been successfully used in the past to induce behavioral and central nervous system related changes in zebrafish. However, it is currently unknown whether chronic ethanol exposure alters ethanol metabolism in adult zebrafish. In the current study we examine the effect of acute ethanol exposure on adult zebrafish behavioral responses, as well as alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activity in the liver. We then examine how two different chronic ethanol exposure paradigms (continuous and repeated ethanol exposure) alter behavioral responses and liver enzyme activity during a subsequent acute ethanol challenge. Acute ethanol exposure increased locomotor activity in a dose-dependent manner. ADH activity was shown to exhibit an inverted U-shaped curve and ALDH activity was decreased by ethanol exposure at all doses. During the acute ethanol challenge, animals that were continuously housed in ethanol exhibited a significantly reduced locomotor response and increased ADH activity, however, ALDH activity did not change. Zebrafish that were repeatedly exposed to ethanol demonstrated a small but significant attenuation of the locomotor response during the acute ethanol challenge but ADH and ALDH activity was similar to controls. Overall, we identified two different chronic ethanol exposure paradigms that differentially alter behavioral and physiological responses in zebrafish. We speculate that these two paradigms may allow dissociation of central nervous system-related and liver enzyme-dependent ethanol induced changes in zebrafish. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Gene networks and toxicity pathways induced by acute cadmium exposure in adult largemouth bass (Micropterus salmoides)

    Energy Technology Data Exchange (ETDEWEB)

    Mehinto, Alvine C., E-mail: alvinam@sccwrp.org [Southern California Coastal Water Research Project, Costa Mesa, CA 92626 (United States); Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Prucha, Melinda S. [Department of Human Genetics, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322 (United States); Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Colli-Dula, Reyna C.; Kroll, Kevin J.; Lavelle, Candice M.; Barber, David S. [Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Vulpe, Christopher D. [Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720 (United States); Denslow, Nancy D. [Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States)

    2014-07-01

    Highlights: • Low-level acute cadmium exposure elicited tissue-specific gene expression changes. • Molecular initiating events included oxidative stress and disruption of DNA repair. • Metallothionein, a marker of metal exposure, was not significantly affected. • We report effects of cadmium on cholesterol metabolism and steroid synthesis. • Diabetic complications and impaired reproduction are potential adverse outcomes. - Abstract: Cadmium is a heavy metal that can accumulate to toxic levels in the environment leading to detrimental effects in animals and humans including kidney, liver and lung injuries. Using a transcriptomics approach, genes and cellular pathways affected by a low dose of cadmium were investigated. Adult largemouth bass were intraperitoneally injected with 20 μg/kg of cadmium chloride (mean exposure level – 2.6 μg of cadmium per fish) and microarray analyses were conducted in the liver and testis 48 h after injection. Transcriptomic profiles identified in response to cadmium exposure were tissue-specific with the most differential expression changes found in the liver tissues, which also contained much higher levels of cadmium than the testis. Acute exposure to a low dose of cadmium induced oxidative stress response and oxidative damage pathways in the liver. The mRNA levels of antioxidants such as catalase increased and numerous transcripts related to DNA damage and DNA repair were significantly altered. Hepatic mRNA levels of metallothionein, a molecular marker of metal exposure, did not increase significantly after 48 h exposure. Carbohydrate metabolic pathways were also disrupted with hepatic transcripts such as UDP-glucose, pyrophosphorylase 2, and sorbitol dehydrogenase highly induced. Both tissues exhibited a disruption of steroid signaling pathways. In the testis, estrogen receptor beta and transcripts linked to cholesterol metabolism were suppressed. On the contrary, genes involved in cholesterol metabolism were highly

  12. Chromosomal bands affected by acute oil exposure and DNA repair errors.

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    Gemma Monyarch

    Full Text Available BACKGROUND: In a previous study, we showed that individuals who had participated in oil clean-up tasks after the wreckage of the Prestige presented an increase of structural chromosomal alterations two years after the acute exposure had occurred. Other studies have also reported the presence of DNA damage during acute oil exposure, but little is known about the long term persistence of chromosomal alterations, which can be considered as a marker of cancer risk. OBJECTIVES: We analyzed whether the breakpoints involved in chromosomal damage can help to assess the risk of cancer as well as to investigate their possible association with DNA repair efficiency. METHODS: Cytogenetic analyses were carried out on the same individuals of our previous study and DNA repair errors were assessed in cultures with aphidicolin. RESULTS: Three chromosomal bands, 2q21, 3q27 and 5q31, were most affected by acute oil exposure. The dysfunction in DNA repair mechanisms, expressed as chromosomal damage, was significantly higher in exposed-oil participants than in those not exposed (p= 0.016. CONCLUSION: The present study shows that breaks in 2q21, 3q27 and 5q31 chromosomal bands, which are commonly involved in hematological cancer, could be considered useful genotoxic oil biomarkers. Moreover, breakages in these bands could induce chromosomal instability, which can explain the increased risk of cancer (leukemia and lymphomas reported in chronically benzene-exposed individuals. In addition, it has been determined that the individuals who participated in clean-up of the oil spill presented an alteration of their DNA repair mechanisms two years after exposure.

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

    OpenAIRE

    H. Vömel; K. Diaz

    2009-01-01

    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 i...

  14. Measurement of Ozone Production Sensor

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    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.

  15. Development of Toxicological Risk Assessment Models for Acute and Chronic Exposure to Pollutants

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    Elke S. Reichwaldt

    2016-08-01

    Full Text Available Alert level frameworks advise agencies on a sequence of monitoring and management actions, and are implemented so as to reduce the risk of the public coming into contact with hazardous substances. Their effectiveness relies on the detection of the hazard, but with many systems not receiving any regular monitoring, pollution events often go undetected. We developed toxicological risk assessment models for acute and chronic exposure to pollutants that incorporate the probabilities that the public will come into contact with undetected pollution events, to identify the level of risk a system poses in regards to the pollutant. As a proof of concept, we successfully demonstrated that the models could be applied to determine probabilities of acute and chronic illness types related to recreational activities in waterbodies containing cyanotoxins. Using the acute model, we identified lakes that present a ‘high’ risk to develop Day Away From Work illness, and lakes that present a ‘low’ or ‘medium’ risk to develop First Aid Cases when used for swimming. The developed risk models succeeded in categorising lakes according to their risk level to the public in an objective way. Modelling by how much the probability of public exposure has to decrease to lower the risks to acceptable levels will enable authorities to identify suitable control measures and monitoring strategies. We suggest broadening the application of these models to other contaminants.

  16. Acute Exposure to Pacific Ciguatoxin Reduces Electroencephalogram Activity and Disrupts Neurotransmitter Metabolic Pathways in Motor Cortex.

    Science.gov (United States)

    Kumar, Gajendra; Au, Ngan Pan Bennett; Lei, Elva Ngai Yu; Mak, Yim Ling; Chan, Leanne Lai Hang; Lam, Michael Hon Wah; Chan, Leo Lai; Lam, Paul Kwan Sing; Ma, Chi Him Eddie

    2016-09-10

    Ciguatera fish poisoning (CFP) is a common human food poisoning caused by consumption of ciguatoxin (CTX)-contaminated fish affecting over 50,000 people worldwide each year. CTXs are classified depending on their origin from the Pacific (P-CTXs), Indian Ocean (I-CTXs), and Caribbean (C-CTXs). P-CTX-1 is the most toxic CTX known and the major source of CFP causing an array of neurological symptoms. Neurological symptoms in some CFP patients last for several months or years; however, the underlying electrophysiological properties of acute exposure to CTXs remain unknown. Here, we used CTX purified from ciguatera fish sourced in the Pacific Ocean (P-CTX-1). Delta and theta electroencephalography (EEG) activity was reduced remarkably in 2 h and returned to normal in 6 h after a single exposure. However, second exposure to P-CTX-1 induced not only a further reduction in EEG activities but also a 2-week delay in returning to baseline EEG values. Ciguatoxicity was detected in the brain hours after the first and second exposure by mouse neuroblastoma assay. The spontaneous firing rate of single motor cortex neuron was reduced significantly measured by single-unit recording with high spatial resolution. Expression profile study of neurotransmitters using targeted profiling approach based on liquid chromatography-tandem mass spectrometry revealed an imbalance between excitatory and inhibitory neurotransmitters in the motor cortex. Our study provides a possible link between the brain oscillations and neurotransmitter release after acute exposure to P-CTX-1. Identification of EEG signatures and major metabolic pathways affected by P-CTX-1 provides new insight into potential biomarker development and therapeutic interventions.

  17. Acute and chronic cadmium exposure promotes E-cadherin degradation in MCF7 breast cancer cells.

    Science.gov (United States)

    Ponce, Esmeralda; Louie, Maggie C; Sevigny, Mary B

    2015-10-01

    Cadmium is an environmental carcinogen that usually enters the body at minute concentrations through diet or cigarette smoke and bioaccumulates in soft tissues. In past studies, cadmium has been shown to contribute to the development of more aggressive cancer phenotypes including increased cell migration and invasion. This study aims to determine if cadmium exposure-both acute and chronic-contributes to breast cancer progression by interfering with the normal functional relationship between E-cadherin and β-catenin. An MCF7 breast cancer cell line (MCF7-Cd) chronically exposed to 10(-7)  M CdCl2 was previously developed and used as a model system to study chronic exposures, whereas parental MCF7 cells exposed to 10(-6)  M CdCl2 for short periods of time were used to study acute exposures. Cadmium exposure of MCF7 cells led to the degradation of the E-cadherin protein via the ubiquitination pathway. This resulted in fewer E-cadherin/β-catenin complexes and the relocation of active β-catenin to the nucleus, where it interacted with transcription factor TCF-4 to modulate gene expression. Interestingly, only cells chronically exposed to cadmium showed a significant decrease in the localization of β-catenin to the plasma membrane and an increased distance between cells. Our data suggest that cadmium exposure promotes breast cancer progression by (1) down-regulating E-cadherin, thus decreasing the number of E-cadherin/β-catenin adhesion complexes, and (2) enhancing the nuclear translocation of β-catenin to increase expression of cancer-promoting proteins (i.e., c-Jun and cyclin D1).

  18. Acute pulmonary toxicity following inhalation exposure to aerosolized VX in anesthetized rats.

    Science.gov (United States)

    Peng, Xinqi; Perkins, Michael W; Simons, Jannitt; Witriol, Alicia M; Rodriguez, Ashley M; Benjamin, Brittany M; Devorak, Jennifer; Sciuto, Alfred M

    2014-06-01

    This study evaluated acute toxicity and pulmonary injury in rats at 3, 6 and 24 h after an inhalation exposure to aerosolized O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX). Anesthetized male Sprague-Dawley rats (250-300 g) were incubated with a glass endotracheal tube and exposed to saline or VX (171, 343 and 514 mg×min/m³ or 0.2, 0.5 and 0.8 LCt₅₀, respectively) for 10 min. VX was delivered by a small animal ventilator at a volume of 2.5 ml × 70 breaths/minute. All VX-exposed animals experienced a significant loss in percentage body weight at 3, 6, and 24 h post-exposure. In comparison to controls, animals exposed to 514 mg×min/m³ of VX had significant increases in bronchoalveolar lavage (BAL) protein concentrations at 6 and 24 h post-exposure. Blood acetylcholinesterase (AChE) activity was inhibited dose dependently at each of the times points for all VX-exposed groups. AChE activity in lung homogenates was significantly inhibited in all VX-exposed groups at each time point. All VX-exposed animals assessed at 20 min and 3, 6 and 24 h post-exposure showed increases in lung resistance, which was prominent at 20 min and 3 h post-exposure. Histopathologic evaluation of lung tissue of the 514 mg×min/m³ VX-exposed animals at 3, 6 and 24 h indicated morphological changes, including perivascular inflammation, alveolar exudate and histiocytosis, alveolar septal inflammation and edema, alveolar epithelial necrosis, and bronchiolar inflammatory infiltrates, in comparison to controls. These results suggest that aerosolization of the highly toxic, persistent chemical warfare nerve agent VX results in acute pulmonary toxicity and lung injury in rats.

  19. Peripheral blood neutrophilia as a biomarker of ozone-induced pulmonary inflammation.

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    Jenny A Bosson

    Full Text Available BACKGROUND: Ozone concentrations are predicted to increase over the next 50 years due to global warming and the increased release of precursor chemicals. It is therefore urgent that good, reliable biomarkers are available to quantify the toxicity of this pollutant gas at the population level. Such a biomarker would need to be easily performed, reproducible, economically viable, and reflective of ongoing pathological processes occurring within the lung. METHODOLOGY: We examined whether blood neutrophilia occurred following a controlled ozone challenge and addressed whether this could serve as a biomarker for ozone-induced airway inflammation. Three separate groups of healthy subjects were exposed to ozone (0.2 ppm, 2h and filtered air (FA on two separate occasions. Peripheral blood samples were collected and bronchoscopy with biopsy sampling and lavages was performed at 1.5h post exposures in group 1 (n=13, at 6h in group 2 (n=15 and at 18h in group 3 (n=15. Total and differential cell counts were assessed in blood, bronchial tissue and airway lavages. RESULTS: In peripheral blood, we observed fewer neutrophils 1.5h after ozone compared with the parallel air exposure (-1.1±1.0x10(9 cells/L, p<0.01, at 6h neutrophil numbers were increased compared to FA (+1.2±1.3x10(9 cells/L, p<0.01, and at 18h this response had fully attenuated. Ozone induced a peak in neutrophil numbers at 6h post exposure in all compartments examined, with a positive correlation between the response in blood and bronchial biopsies. CONCLUSIONS: These data demonstrate a systemic neutrophilia in healthy subjects following an acute ozone exposure, which mirrors the inflammatory response in the lung mucosa and lumen. This relationship suggests that blood neutrophilia could be used as a relatively simple functional biomarker for the effect of ozone on the lung.

  20. Ozone-Induced Type 2 Immunity in Nasal Airways. Development and Lymphoid Cell Dependence in Mice.

    Science.gov (United States)

    Ong, Chee Bing; Kumagai, Kazuyoshi; Brooks, Phillip T; Brandenberger, Christina; Lewandowski, Ryan P; Jackson-Humbles, Daven N; Nault, Rance; Zacharewski, Timothy R; Wagner, James G; Harkema, Jack R

    2016-03-01

    Inhalation exposures to ozone commonly encountered in photochemical smog cause airway injury and inflammation. Elevated ambient ozone concentrations have been epidemiologically associated with nasal airway activation of neutrophils and eosinophils. In the present study, we elucidated the temporal onset and lymphoid cell dependency of eosinophilic rhinitis and associated epithelial changes in mice repeatedly exposed to ozone. Lymphoid cell-sufficient C57BL/6 mice were exposed to 0 or 0.5 parts per million (ppm) ozone for 1, 2, 4, or 9 consecutive weekdays (4 h/d). Lymphoid cell-deficient, Rag2(-/-)Il2rg(-/-) mice were similarly exposed for 9 weekdays. Nasal tissues were taken at 2 or 24 hours after exposure for morphometric and gene expression analyses. C57BL/6 mice exposed to ozone for 1 day had acute neutrophilic rhinitis, with airway epithelial necrosis and overexpression of mucosal Ccl2 (MCP-1), Ccl11 (eotaxin), Cxcl1 (KC), Cxcl2 (MIP-2), Hmox1, Il1b, Il5, Il6, Il13, and Tnf mRNA. In contrast, 9-day ozone exposure elicited type 2 immune responses in C57BL/6 mice, with mucosal mRNA overexpression of Arg1, Ccl8 (MCP-2), Ccl11, Chil4 (Ym2), Clca1 (Gob5), Il5, Il10, and Il13; increased density of mucosal eosinophils; and nasal epithelial remodeling (e.g., hyperplasia/hypertrophy, mucous cell metaplasia, hyalinosis, and increased YM1/YM2 proteins). Rag2(-/-)Il2rg(-/-) mice exposed to ozone for 9 days, however, had no nasal pathology or overexpression of transcripts related to type 2 immunity. These results provide a plausible paradigm for the activation of eosinophilic inflammation and type 2 immunity found in the nasal airways of nonatopic individuals subjected to episodic exposures to high ambient ozone.

  1. Histopathological alterations of white seabass, Lates calcarifer, in acute and subchronic cadmium exposure

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    Thophon, S.; Kruatrachue, M.; Upatham, E.S.; Pokethitiyook, P.; Sahaphong, S.; Jaritkhuan, S

    2003-03-01

    White seabass responded differently to cadmium at chronic and subchronic levels. - Histopathological alterations to white seabass, Lates calcarifer aged 3 months in acute and subchronic cadmium exposure were studied by light and scanning electron microscopy. The 96-h LC{sub 50} values of cadmium to L. calcarifer was found to be 20.12{+-}0.61 mg/l and the maximum acceptable toxicant concentration (MATC) was 7.79 mg/l. Fish were exposed to 10 and 0.8 mg/l of Cd (as CdCl{sub 2}H{sub 2}O) for 96 h and 90 days, respectively. The study showed that gill lamellae and kidney tubules were the primary target organs for the acute toxic effect of cadmium while in the subchronic exposure, the toxic effect to gills was less than that of kidney and liver. Gill alterations included edema of the epithelial cells with the breakdown of pillar cell system, aneurisms with some ruptures, hypertrophy and hyperplasia of epithelial and chloride cells. The liver showed blood congestion in sinusoids and hydropic swelling of hepatocytes, vacuolation and dark granule accumulation. Lipid droplets and glycogen content were observed in hepatocytes at the second and third month of subchronic exposure. The kidney showed hydropic swelling of tubular cell vacuolation and numerous dark granule accumulation in many tubules. Tubular degeneration and necrosis were seen in some areas.

  2. Acute toxicity effects of Prunus avium fruit extract and selection of optimum dose against radiation exposure.

    Science.gov (United States)

    Sisodia, Rashmi; Sharma, K; Singh, Smita

    2009-01-01

    The objective of the study was to evaluate the acute toxicity of different doses of the methanolic extract of the fruit pulp of Prunus avium (family Rosaceae), which is used ethno-medicinally for the treatment of various diseases, and to find out the optimal dose of Prunus avium extract against 10 Gy gamma-radiation exposure. To test acute toxicity in mice, different doses of PAE (Prunus avium fruit extract) were given orally for 15 consecutive days, after which the animals were observed for another 15 days; the LD50/15 of the methanolic extract was calculated to be 4.947 gm/kg body weight (b.wt). In optimum dose selection against radiation exposure, oral administration of 450 mg/kg b.wt/d of PAE for 15 consecutive days before exposure to 10 Gy of gamma-radiation was found to afford maximum protection in terms of body weight and survivability of the mice in comparison to other doses.

  3. Temporal changes in rat liver gene expression after acute cadmium and chromium exposure.

    Directory of Open Access Journals (Sweden)

    Michael S Madejczyk

    Full Text Available U.S. Service Members and civilians are at risk of exposure to a variety of environmental health hazards throughout their normal duty activities and in industrial occupations. Metals are widely used in large quantities in a number of industrial processes and are a common environmental toxicant, which increases the possibility of being exposed at toxic levels. While metal toxicity has been widely studied, the exact mechanisms of toxicity remain unclear. In order to further elucidate these mechanisms and identify candidate biomarkers, rats were exposed via a single intraperitoneal injection to three concentrations of CdCl2 and Na(2Cr(2O(7, with livers harvested at 1, 3, or 7 days after exposure. Cd and Cr accumulated in the liver at 1 day post exposure. Cd levels remained elevated over the length of the experiment, while Cr levels declined. Metal exposures induced ROS, including hydroxyl radical (•OH, resulting in DNA strand breaks and lipid peroxidation. Interestingly, ROS and cellular damage appeared to increase with time post-exposure in both metals, despite declines in Cr levels. Differentially expressed genes were identified via microarray analysis. Both metals perturbed gene expression in pathways related to oxidative stress, metabolism, DNA damage, cell cycle, and inflammatory response. This work provides insight into the temporal effects and mechanistic pathways involved in acute metal intoxication, leading to the identification of candidate biomarkers.

  4. Temporal Changes in Rat Liver Gene Expression after Acute Cadmium and Chromium Exposure

    Science.gov (United States)

    Madejczyk, Michael S.; Baer, Christine E.; Dennis, William E.; Minarchick, Valerie C.; Leonard, Stephen S.; Jackson, David A.; Stallings, Jonathan D.; Lewis, John A.

    2015-01-01

    U.S. Service Members and civilians are at risk of exposure to a variety of environmental health hazards throughout their normal duty activities and in industrial occupations. Metals are widely used in large quantities in a number of industrial processes and are a common environmental toxicant, which increases the possibility of being exposed at toxic levels. While metal toxicity has been widely studied, the exact mechanisms of toxicity remain unclear. In order to further elucidate these mechanisms and identify candidate biomarkers, rats were exposed via a single intraperitoneal injection to three concentrations of CdCl2 and Na2Cr2O7, with livers harvested at 1, 3, or 7 days after exposure. Cd and Cr accumulated in the liver at 1 day post exposure. Cd levels remained elevated over the length of the experiment, while Cr levels declined. Metal exposures induced ROS, including hydroxyl radical (•OH), resulting in DNA strand breaks and lipid peroxidation. Interestingly, ROS and cellular damage appeared to increase with time post-exposure in both metals, despite declines in Cr levels. Differentially expressed genes were identified via microarray analysis. Both metals perturbed gene expression in pathways related to oxidative stress, metabolism, DNA damage, cell cycle, and inflammatory response. This work provides insight into the temporal effects and mechanistic pathways involved in acute metal intoxication, leading to the identification of candidate biomarkers. PMID:25993096

  5. Acute paraquat exposure impairs colonic motility by selectively attenuating nitrergic signalling in the mouse.

    Science.gov (United States)

    Diss, Lucy; Dyball, Sarah; Ghela, Tina; Golding, Jonathan; Morris, Rachel; Robinson, Stephen; Tucker, Rosemary; Walter, Talia; Young, Paul; Allen, Marcus; Fidalgo, Sara; Gard, Paul; Mabley, Jon; Patel, Bhavik; Chatterjee, Prabal; Yeoman, Mark

    2016-02-01

    Paraquat, a common herbicide, is responsible for large numbers of deaths worldwide through both deliberate and accidental ingestion. Previous studies have eluded that the bioavailability of paraquat increases substantially with increasing dose and that these changes may in part be due to the effects that these high concentrations have on the gastrointestinal tract (GI tract). To date, the actions of acute, high concentrations (20mM for 60 min) of paraquat on the GI tract, particularly the colon which is a major site of paraquat absorption, are unknown. This study examined the effects of acute paraquat administration on colonic motility in the C57BL/6 mouse. Acute paraquat exposure decreased colonic motility and the amplitude of colonic migrating motor complexes (CMMCs), which are major motor patterns involved in faecal pellet propulsion. In isolated segments of distal colon, paraquat increased resting tension and markedly attenuated electrical field stimulation-evoked relaxations. Pharmacological dissection of paraquat's mechanism of action on both the CMMCs and field stimulated tissue using the nitric oxide synthase inhibitor NG-nitro-L-arginine and direct measurement of NO release from the myenteric plexus, demonstrated that paraquat selectively attenuates nitrergic signalling pathways. These changes did not appear to be due to alterations in colonic oxidative stress, inflammation or complex 1 activity, but were most likely caused by paraquat's ability to act as a redox couple. In summary, these data demonstrate that acute paraquat exposure attenuates colonic transit. These changes may facilitate the absorption of paraquat into the circulation and so facilitate its toxicity.

  6. Agricultural adjuvants: acute mortality and effects on population growth rate of Daphnia pulex after chronic exposure.

    Science.gov (United States)

    Stark, John D; Walthall, William K

    2003-12-01

    Acute and chronic toxicity of eight agricultural adjuvants (Bond, Kinetic, Plyac, R-11, Silwet L-77, Sylgard 309, X-77, and WaterMaxx) to Daphnia pulex were evaluated with 48-h acute lethal concentration estimates (LC50) and a 10-d population growth-rate measurement, the instantaneous rate of increase (r1). Based on LC50, the order of toxicity was R-11 > X-77 = Sylgard 309 = Silwet L-77 > Kinetic > Bond > Plyac > WaterMaxx; all LC50 estimates were higher than the expected environmental concentration (EEC) of 0.79 mg/L, indicating that none of these adjuvants should cause high levels of mortality in wild D. pulex populations. Extinction, defined as negative population growth rate, occurred after exposure to 0.9 mg/L R-11, 13 mg/L X-77, 25 mg/L Kinetic, 28 mg/L Silwet, 18 mg/L Sylgard, 450 mg/L Bond, 610 mg/L Plyac, and 1,600 mg/L WaterMaxx. Concentrations that caused extinction were substantially below the acute LC50 for R-11, Kinetic, Plyac, X-77, and Bond. The no-observable-effects concentration (NOEC) and lowest-observable-effects concentration (LOEC) for the number of offspring per surviving female after exposure to R-11 were 0.5 and 0.75 mg/L, respectively. The NOEC and LOEC for population size after exposure to R-11 were (1.25 and 0.5 mg/L, respectively. Both of these values were lower than the EEC, indicating that R-11 does have the potential to cause damage to D. pulex populations after application at recommended field rates. The wide range of concentrations causing extinction makes it difficult to generalize about the potential impacts that agricultural adjuvants might have on aquatic ecosystems. Therefore, additional studies that examine effects on other nontarget organisms and determine residues in aquatic ecosystems may be warranted.

  7. Ambient Ozone and Emergency Department Visits for Cellulitis

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    Mieczysław Szyszkowicz

    2010-11-01

    Full Text Available Objectives were to assess and estimate an association between exposure to ground-level ozone and emergency department (ED visits for cellulitis. All ED visits for cellulitis in Edmonton, Canada, in the period April 1992–March 2002 (N = 69,547 were examined. Case-crossover design was applied to estimate odds ratio (OR, and 95% confidence interval per one interquartile range (IQR increase in ozone concentration (IQR = 14.0 ppb. Delay of ED visit relating to exposure was probed using 0- to 5-day exposure lags. For all patients in the all months (January–December and lags 0 to 2 days, OR = 1.05 (1.02, 1.07. For male patients during the cold months (October-March: OR = 1.05 (1.02, 1.09 for lags 0 and 2 and OR = 1.06 (1.02, 1.10 for lag 3. For female patients in the warm months (April-September: OR = 1.12 (1.06, 1.18 for lags 1 and 2. Cellulitis developing on uncovered (more exposed skin was analyzed separately, observed effects being stronger. Cellulitis may be associated with exposure to ambient ground level ozone; the exposure may facilitate cellulitis infection and aggravate acute symptoms.

  8. Acute Inhalation Exposure to Titanium Ethanolate as a Possible Cause of Metal Fume Fever

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    M Ahmadimanesh

    2014-04-01

    Full Text Available Occupational inhalation exposure to noxious agents is not uncommon. Herein, we present a 26-year-old male student who had accidental acute inhalation exposure to a large quantity of titanium ethanolate and hydrogen chloride in chemistry lab. He was referred to the emergency department of our hospital with low-grade fever, dyspnea, headache, fatigue and myalgia. After 24 hrs of symptomatic treatment (oxygen therapy and acetaminophen, the fever was subsided and the patient discharged home in a good clinical condition. The presented symptoms could be interpreted as a form of metal fume fever. It can therefore be concluded that organo-metallic compound of titanium metal may have the potential to produce metal fume fever in human.

  9. Genome-wide gene expression profiling of acute metal exposures in male zebrafish

    Directory of Open Access Journals (Sweden)

    Christine E. Baer

    2014-12-01

    Full Text Available To capture global responses to metal poisoning and mechanistic insights into metal toxicity, gene expression changes were evaluated in whole adult male zebrafish following acute 24 h high dose exposure to three metals with known human health risks. Male adult zebrafish were exposed to nickel chloride, cobalt chloride or sodium dichromate at concentrations corresponding to their respective 96 h LC20, LC40 and LC60 (i.e. 96 h concentrations at which 20%, 40% and 60% lethality is expected, respectively. Histopathology was performed on a subset of metal-exposed zebrafish to phenotypically anchor transcriptional changes associated with each metal exposure. Here we describe in detail the contents and quality controls for the gene expression and other data associated with the study published by Hussainzada and colleagues in BMC Pharmacology and Toxicology (Hussainzada et al., 2014 with the data uploaded to Gene Expression Omnibus (accession number GSE50648.

  10. Genome-wide gene expression profiling of acute metal exposures in male zebrafish

    Science.gov (United States)

    Baer, Christine E.; Ippolito, Danielle L.; Hussainzada, Naissan; Lewis, John A.; Jackson, David A.; Stallings, Jonathan D.

    2014-01-01

    To capture global responses to metal poisoning and mechanistic insights into metal toxicity, gene expression changes were evaluated in whole adult male zebrafish following acute 24 h high dose exposure to three metals with known human health risks. Male adult zebrafish were exposed to nickel chloride, cobalt chloride or sodium dichromate at concentrations corresponding to their respective 96 h LC20, LC40 and LC60 (i.e. 96 h concentrations at which 20%, 40% and 60% lethality is expected, respectively). Histopathology was performed on a subset of metal-exposed zebrafish to phenotypically anchor transcriptional changes associated with each metal exposure. Here we describe in detail the contents and quality controls for the gene expression and other data associated with the study published by Hussainzada and colleagues in BMC Pharmacology and Toxicology (Hussainzada et al., 2014) with the data uploaded to Gene Expression Omnibus (accession number GSE50648). PMID:26484131

  11. Acute vertigo in an anesthesia provider during exposure to a 3T MRI scanner.

    Science.gov (United States)

    Gorlin, Andrew; Hoxworth, Joseph M; Pavlicek, William; Thunberg, Christopher A; Seamans, David

    2015-01-01

    Vertigo induced by exposure to the magnetic field of a magnetic resonance imaging (MRI) scanner is a well-known phenomenon within the radiology community but is not widely appreciated by other clinical specialists. Here, we describe a case of an anesthetist experiencing acute vertigo while providing sedation to a patient undergoing a 3 Tesla MRI scan. After discussing previous reports, and the evidence surrounding MRI-induced vertigo, we review potential etiologies that include the effects of both static and time-varying magnetic fields on the vestibular apparatus. We conclude our review by discussing the occupational standards that exist for MRI exposure and methods to minimize the risks of MRI-induced vertigo for clinicians working in the MRI environment.

  12. Ozone exposure induces the activation of leaf senescence-related processes and morphological and growth changes in seedlings of Mediterranean tree species.

    Science.gov (United States)

    Ribas, Angela; Peñuelas, Josep; Elvira, Susana; Gimeno, Benjamín S

    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(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 delta(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(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(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.

  13. Potential use of the PRI and active fluorescence for the diagnosis of the physiological state of plants under ozone exposure and high atmospheric vapor pressure deficit.

    Science.gov (United States)

    Merlier, Elodie; Hmimina, Gabriel; Bagard, Matthieu; Dufrêne, Eric; Soudani, Kamel

    2017-08-09

    Assessing photosynthesis rates with remote sensing is important for tracking the physiological state of plants. The photochemical reflectance index (PRI) is a good estimator of short-term light-use efficiency (LUE) at the leaf scale but its responses to environmental factors are poorly understood. In this study, we assessed changes in the responses of the PRI to ozone exposure and to an increase in atmospheric drought (separately and combined) in oak (Quercus robur) and holm oak (Quercus ilex) that were planted in climatic cells under controlled conditions. The aim was to evaluate the ability of the PRI as a relevant indicator to assess the impact of abiotic factors on photosynthesis. Leaf-scale measurements of biochemical, physiological and spectral properties, including the PRI in dim light on dark-adapted leaves (PRI0), kinetics of PRI responses to PAR variations (photosynthetically active radiation), and leaf chlorophyll fluorescence parameters were performed. The results show that PRI0 is a good proxy of the leaf chlorophyll content, and is correlated to chlorophyll fluorescence parameters on dark adapted leaves (Fo, Fm). The correction of the PRI from the leaf chlorophyll content variations (PRIc) significantly improves correlations between the PRI and NPQ (non-photochemical quenching). The variability of PARsat (estimated PAR value at PRI saturation using PRI vs. PAR relationships) depends on ozone exposure and on the increase in atmospheric vapor pressure deficit. For Quercus robur, results highlight that PARsat is linked to abiotic stress indicating that the PRI may be used as a relevant indicator of abiotic factors limiting the photosynthesis. Quercus ilex did not show significant variability in PRI0 and PARsat, which suggest that it is a more drought resistant species than Q. robur.

  14. Acute and chronic effects of erythromycin exposure on oxidative stress and genotoxicity parameters of Oncorhynchus mykiss

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, S., E-mail: up201208875@fc.up.pt [Departamento de Biologia da Faculdade de Ciências da Universidade do Porto (FCUP), Rua do Campo Alegre s/n, 4169–007 Porto (Portugal); Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Rua dos Bragas 289, 4050–123 Porto (Portugal); Antunes, S.C. [Departamento de Biologia da Faculdade de Ciências da Universidade do Porto (FCUP), Rua do Campo Alegre s/n, 4169–007 Porto (Portugal); Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Rua dos Bragas 289, 4050–123 Porto (Portugal); Correia, A.T. [Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Rua dos Bragas 289, 4050–123 Porto (Portugal); Faculdade de Ciências da Saúde da Universidade Fernando Pessoa (FCS-UFP), Rua Carlos da Maia, 296, 4200–150, Porto (Portugal); Nunes, B. [Centro de Estudos do Ambiente e do Mar (CESAM), Campus de Santiago, Universidade de Aveiro, 3810–193 Aveiro (Portugal); Departamento de Biologia, Universidade de Aveiro, Campus de Santiago, 3810–193 Aveiro (Portugal)

    2016-03-01

    Erythromycin (ERY) is a macrolide antibiotic used in human and veterinary medicine, and has been detected in various aquatic compartments. Recent studies have indicated that this compound can exert biological activity on non-target organisms environmentally exposed. The present study aimed to assess the toxic effects of ERY in Oncorhynchus mykiss after acute and chronic exposures. The here adopted strategy involved exposure to three levels of ERY, the first being similar to concentrations reported to occur in the wild, thus ecologically relevant. Catalase (CAT), total glutathione peroxidase (GPx), glutathione reductase (GRed) activities and lipid peroxidation (TBARS levels) were quantified as oxidative stress biomarkers in gills and liver. Genotoxic endpoints, reflecting different types of genetic damage in blood cells, were also determined, by performing analysis of genetic damage (determination of the genetic damage index, GDI, measured by comet assay) and of erythrocytic nuclear abnormalities (ENAs). The results suggest the occurrence of a mild, but significant, oxidative stress scenario in gills. For acutely exposed organisms, significant alterations were observed in CAT and GRed activities, and also in TBARS levels, which however are modifications with uncertain biological interpretation, despite indicating involvement of an oxidative effect and response. After chronic exposure, a significant decrease of CAT activity, increase of GPx activity and TBARS levels in gills was noticed. In liver, significant decrease in TBARS levels were observed in both exposures. Comet and ENAs assays indicated significant increases on genotoxic damage of O. mykiss, after erythromycin exposures. This set of data (acute and chronic) suggests that erythromycin has the potential to induce DNA strand breaks in blood cells, and demonstrate the induction of chromosome breakage and/or segregational abnormalities. Overall results indicate that both DNA damaging effects induced by

  15. 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

  16. Susceptibility of adult and senescent brown norway rats to repeated ozone exposure: An assessment of behavior, serum biochemistry and cardiopulmonary function

    Science.gov (United States)

    Tropospheric ozone (03) is a pervasive air pollutant that produces pulmonary and cardiovascular dysfunction and there is growing evidence suggesting neurological dysfunction as well. Young and old individuals are generally recognized as being susceptible to ozone toxicity; howeve...

  17. Gene expression changes in female zebrafish (Danio rerio) brain in response to acute exposure to methylmercury

    Science.gov (United States)

    Richter, Catherine A.; Garcia-Reyero, Natàlia; Martyniuk, Chris; Knoebl, Iris; Pope, Marie; Wright-Osment, Maureen K.; Denslow, Nancy D.; Tillitt, Donald E.

    2011-01-01

    Methylmercury (MeHg) is a potent neurotoxicant and endocrine disruptor that accumulates in aquatic systems. Previous studies have shown suppression of hormone levels in both male and female fish, suggesting effects on gonadotropin regulation in the brain. The gene expression profile in adult female zebrafish whole brain induced by acute (96 h) MeHg exposure was investigated. Fish were exposed by injection to 0 or 0.5(mu or u)g MeHg/g. Gene expression changes in the brain were examined using a 22,000-feature zebrafish microarray. At a significance level of pgenes were up-regulated and 76 genes were down-regulated in response to MeHg exposure. Individual genes exhibiting altered expression in response to MeHg exposure implicate effects on glutathione metabolism in the mechanism of MeHg neurotoxicity. Gene ontology (GO) terms significantly enriched among altered genes included protein folding, cell redox homeostasis, and steroid biosynthetic process. The most affected biological functions were related to nervous system development and function, as well as lipid metabolism and molecular transport. These results support the involvement of oxidative stress and effects on protein structure in the mechanism of action of MeHg in the female brain. Future studies will compare the gene expression profile induced in response to MeHg with that induced by other toxicants and will investigate responsive genes as potential biomarkers of MeHg exposure.

  18. Exposure to Discrimination and Heart Rate Variability Reactivity to Acute Stress among Women with Diabetes.

    Science.gov (United States)

    Wagner, Julie; Lampert, Rachel; Tennen, Howard; Feinn, Richard

    2015-08-01

    Exposure to racial discrimination has been linked to physiological reactivity. This study investigated self-reported exposure to racial discrimination and parasympathetic [high-frequency heart rate variability (HF-HRV)] and sympathetic (norepinephrine and cortisol) activity at baseline and then again after acute laboratory stress. Lifetime exposure to racial discrimination was measured with the Schedule of Racist Events scale. Thirty-two women (16 Black and 16 White) with type 2 diabetes performed a public speaking stressor. Beat-to-beat intervals were recorded on electrocardiograph recorders, and HF-HRV was calculated using spectral analysis and natural log transformed. Norepinephrine and cortisol were measured in blood. Higher discrimination predicted lower stressor HF-HRV, even after controlling for baseline HF-HRV. When race, age, A1c and baseline systolic blood pressure were also controlled, racial discrimination remained a significant independent predictor of stressor HF-HRV. There was no association between lifetime discrimination and sympathetic markers. In conclusion, preliminary data suggest that among women with type 2 diabetes mellitus (T2DM), exposure to racial discrimination is adversely associated with parasympathetic, but not sympathetic, reactivity. Copyright © 2013 John Wiley & Sons, Ltd.

  19. Ambient fine particulate matter and ozone exposures induce inflammation in epicardial and perirenal adipose tissues in rats fed a high fructose diet.

    Science.gov (United States)

    Sun, Lixian; Liu, Cuiqing; Xu, Xiaohua; Ying, Zhekang; Maiseyeu, Andrei; Wang, Aixia; Allen, Katryn; Lewandowski, Ryan P; Bramble, Lori A; Morishita, Masako; Wagner, James G; Dvonch, J; Sun, Zhichao; Yan, Xiaowei; Brook, Robert D; Rajagopalan, Sanjay; Harkema, Jack R; Sun, Qinghua; Fan, Zhongjie

    2013-08-22

    Inflammation and oxidative stress play critical roles in the pathogenesis of inhaled air pollutant-mediated metabolic disease. Inflammation in the adipose tissues niches are widely believed to exert important effects on organ dysfunction. Recent data from both human and animal models suggest a role for inflammation and oxidative stress in epicardial adipose tissue (EAT) as a risk factor for the development of cardiovascular disease. We hypothesized that inhalational exposure to concentrated ambient fine particulates (CAPs) and ozone (O3) exaggerates inflammation and oxidative stress in EAT and perirenal adipose tissue (PAT). Eight- week-old Male Sprague-Dawley rats were fed a normal diet (ND) or high fructose diet (HFr) for 8 weeks, and then exposed to ambient AIR, CAPs at a mean of 356 μg/m3, O3 at 0.485 ppm, or CAPs (441 μg/m3) + O3 (0.497 ppm) in Dearborn, MI, 8 hours/day, 5 days/week, for 9 days over 2 weeks. EAT and PAT showed whitish color in gross, and less mitochondria, higher mRNA expression of white adipose specific and lower brown adipose specific genes than in brown adipose tissues. Exposure to CAPs and O3 resulted in the increase of macrophage infiltration in both EAT and PAT of HFr groups. Proinflammatory genes of Tnf-α, Mcp-1 and leptin were significantly upregulated while IL-10 and adiponectin, known as antiinflammatory genes, were reduced after the exposures. CAPs and O3 exposures also induced an increase in inducible nitric oxide synthase (iNOS) protein expression, and decrease in mitochondrial area in EAT and PAT. We also found significant increases in macrophages of HFr-O3 rats. The synergetic interaction of HFr and dirty air exposure on the inflammation was found in most of the experiments. Surprisingly, exposure to CAPs or O3 induced more significant inflammation and oxidative stress than co-exposure of CAPs and O3 in EAT and PAT. EAT and PAT are both white adipose tissues. Short-term exposure to CAPs and O3, especially with high

  20. ACUTE OZONE-INDUCED INFLAMMATORY GENE EXPRESSION IN THE RAT LUNG IS NOT RELATED TO LEVELS OF ANTIOXIDANTS IN THE LAVAGE FLUID

    Science.gov (United States)

    ABSTRACT BODY: Ozone causes oxidative stress and lung inflammation. We hypothesized that rat strains with or without genetic susceptibility to cardiovascular disease will have different antioxidant levels in alveolar lining, and that ozone induced inflammatory gene expression wil...

  1. Global health and economic impacts of future ozone pollution

    Science.gov (United States)

    Selin, N. E.; Wu, S.; Nam, K. M.; Reilly, J. M.; Paltsev, S.; Prinn, R. G.; Webster, M. D.

    2009-10-01

    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.

  2. Acute health effects associated with exposure to volcanic air pollution (vog) from increased activity at Kilauea Volcano in 2008.

    Science.gov (United States)

    Longo, Bernadette M; Yang, Wei; Green, Joshua B; Crosby, Frederick L; Crosby, Vickie L

    2010-01-01

    In 2008, the Kilauea Volcano on the island of Hawai'i increased eruption activity and emissions of sulfurous volcanic air pollution called vog. The purpose of this study was to promptly assess for a relative increase in cases of medically diagnosed acute illnesses in an exposed Hawaiian community. Using a within-clinic retrospective cohort design, comparisons were made for visits of acute illnesses during the 14 wk prior to the increased volcanic emissions (low exposure) to 14 wk of high vog exposure when ambient sulfur dioxide was threefold higher and averaged 75 parts per billion volume per day. Logistic regression analysis estimated effect measures between the low- and high-exposure cohorts for age, gender, race, and smoking status. There were statistically significant positive associations between high vog exposure and visits for medically diagnosed cough, headache, acute pharyngitis, and acute airway problems. More than a sixfold increase in odds was estimated for visits with acute airway problems, primarily experienced by young Pacific Islanders. These findings suggest that the elevated volcanic emissions in 2008 were associated with increased morbidity of acute illnesses in age and racial subgroups of the general Hawaiian population. Continued investigation is crucial to fully assess the health impact of this natural source of sulfurous air pollution. Culturally appropriate primary- and secondary-level health prevention initiatives are recommended for populations in Hawai'i and volcanically active areas worldwide.

  3. Neutrophil influx measured in nasal lavages of humans exposed to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Graham, D.; Henderson, F.; House, D.

    1988-05-01

    Neutrophils (PMNs) obtained by nasal lavage were counted to determine if ozone, an oxidant air pollutant, induces an acute inflammatory response in the upper respiratory tract (URT) of humans. Background data were obtained by the nasal lavages from 200 nonexperimentally exposed subjects. Then, using a known inflammatory agent for the URT, rhinovirus-type 39, the induction, peak, and resolution of an acute inflammatory response was shown to be documented by the nasal lavage PMN counts. To determined if ozone induces this response, 41 subjects were exposed to either filtered air or 0.5 ppm ozone for 4 hr, on 2 consecutive days. Nasal lavages were taken pre-, immediately post each exposure, and 22 hr following the last exposure. Lavage PMN counts increased significantly (p = .005) in the ozone-exposed group, with 3.5-, 6.5-, and 3.9-fold increases over the air-exposed group at the post 1, pre 2, and post 2 time points, respectively. Ozone induces an inflammatory response in the URT of humans, and nasal lavage PMN counts are useful to assay the inflammatory properties of air pollutants.

  4. Evaluating Systemic Toxicity in Rabbits after Acute Ocular Exposure to Irritant Chemicals

    Directory of Open Access Journals (Sweden)

    Reshma Sebastian Cherian

    2014-01-01

    Full Text Available Acute systemic toxicity via ocular exposure route is not a well understood aspect. Any material/drug/chemical that comes in contact with the eye can evade the first pass metabolism and enter the systemic circulation through the conjunctival blood vessels or via the nasolacrimal route. In this study, the effect of ocular irritant chemicals on the systemic toxicity was assessed in rabbit. Eyes of rabbits were exposed to known ocular irritant (cetyl pyridinium chloride, sodium salicylate, imidazole, acetaminophen, and nicotinamide for 24 h and scored. After a period of 72 h, blood was collected from the animals for examining the hematological and biochemical parameters. The animals were then sacrificed and the eyes were collected for histopathology and cytokine analysis by ELISA. Splenocyte proliferation was assessed by tritiated thymidine incorporation assay. The liver and brain of the treated animals were retrieved for evaluating oxidative damage. The chemicals showed moderate to severe eye irritation. Inflammation was not evident in the histopathology but proinflammatory markers were significantly high. The splenocyte proliferation capacity was undeterred. And there was minimal oxidative stress in the brain and liver. In conclusion, acute exposure of ocular irritants was incapable of producing a prominent systemic side effect in the current scenario.

  5. Acute radiation enteritis caused by dose-dependent radiation exposure in dogs: experimental research.

    Science.gov (United States)

    Xu, Wenda; Chen, Jiang; Xu, Liu; Li, Hongyu; Guo, Xiaozhong

    2014-12-01

    Accidental or intended radiation exposure in mass casualty settings presents a serious and on-going threat. The development of mitigating and treating agents requires appropriate animal models. Unfortunately, the majority of research on radiation enteritis in animals has lacked specific assessments and targeted therapy. Our study showed beagle dogs, treated by intensity-modulated radiation therapy (IMRT) for abdominal irradiation, were administered single X-ray doses of 8-30 Gy. The degree of intestinal tract injury for all of the animals after radiation exposure was evaluated with regard to clinical syndrome, endoscopic findings, histological features, and intestinal function. The range of single doses (8 Gy, 10-14 Gy, and 16-30 Gy) represented the degree of injury (mild, moderate, and severe, respectively). Acute radiation enteritis included clinical syndrome with fever, vomiting, diarrhea, hemafecia, and weight loss; typical endoscopic findings included edema, bleeding, mucosal abrasions, and ulcers; and intestinal biopsy results revealed mucosal necrosis, erosion, and loss, inflammatory cell infiltration, hemorrhage, and congestion. Changes in serum diamine oxides (DAOs) and d-xylose represented intestinal barrier function and absorption function, respectively, and correlated with the extent of damage (P enteritis, thus obtaining a relatively objective evaluation of intestinal tract injury based on clinical performance and laboratory examination. The method of assessment of the degree of intestinal tract injury after abdominal irradiation could be beneficial in the development of novel and effective therapeutic strategies for acute radiation enteritis.

  6. Acute on chronic exposure to endotoxin is associated with enhanced chemoreflex responses in preterm fetal sheep.

    Science.gov (United States)

    Booth, Lindsea C; Drury, Paul P; Muir, Cameron; Jensen, Ellen C; Gunn, Alistair J; Bennet, Laura

    2013-05-15

    There is increasing evidence that exposure to infection can sensitize the fetus to subsequent hypoxic injury. However, it is unclear whether this involves compromise of the fetal cardiovascular adaptation to acute asphyxia. Chronically instrumented 103-day-old (0.7 gestational age, term is 147 days) fetal sheep in utero were randomized to receive either gram-negative lipopolysaccharide (LPS) as a continuous low-dose infusion for 120 h plus boluses of 1 μg LPS at 48, 72, and 96 h with asphyxia at 102 h (i.e., 6 h after the final LPS bolus) induced by umbilical cord occlusion for 15 min (LPS treated, n = 8), or the same volume of saline plus occlusion (saline treated, n = 7). Fetuses were killed 5 days after occlusion. LPS was associated with a more rapid fall in fetal heart rate at the onset of occlusion (P fall in CaBF to similar values as saline controls during occlusion. There were no differences between the groups in femoral blood flow before or during occlusion. Contrary to our initial hypothesis, acute on chronic exposure to LPS was associated with more rapid cardiovascular adaptation to umbilical cord occlusion.

  7. Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure

    Science.gov (United States)

    Nelson, Gregory A.; Simonsen, Lisa; Huff, Janice L.

    2016-01-01

    Possible acute and late risks to the central nervous system (CNS) from galactic cosmic rays (GCR) and solar particle events (SPE) are concerns for human exploration of space. Acute CNS risks may include: altered cognitive function, reduced motor function, and behavioral changes, all of which may affect performance and human health. Late CNS risks may include neurological disorders such as Alzheimer's disease (AD), dementia and premature aging. Although detrimental CNS changes are observed in humans treated with high-dose radiation (e.g., gamma rays and 9 protons) for cancer and are supported by experimental evidence showing neurocognitive and behavioral effects in animal models, the significance of these results on the morbidity to astronauts has not been elucidated. There is a lack of human epidemiology data on which to base CNS risk estimates; therefore, risk projection based on scaling to human data, as done for cancer risk, is not possible for CNS risks. Research specific to the spaceflight environment using animal and cell models must be compiled to quantify the magnitude of CNS changes in order to estimate this risk and to establish validity of the current permissible exposure limits (PELs). In addition, the impact of radiation exposure in combination with individual sensitivity or other space flight factors, as well as assessment of the need for biological/pharmaceutical countermeasures, will be considered after further definition of CNS risk occurs.

  8. [Reactive microglial changes in rat neocortex and hippocampus after exposure to acute perinatal hypoxia].

    Science.gov (United States)

    Khozhaĭ, L I; Otellin, V A

    2013-01-01

    The dynamics of reactive changes of a population density of microglial cells and the reversibility of their phenotypic forms were studied in the brain of neonatal rats at different time intervals after 1 hr-long exposure to acute normobaric hypoxia in the pressure chamber at the second postnatal day. Different areas of the neocortex (frontal, motor, somatosensory and visual) and of the hippocampus (CAI, CA3, CA4 and fascia dentata) were examined 1 hr, 3 hrs, 1 and 5 days after exposure to hypoxia. Microglial cells were demonstrated using an immunocytochemical staining with the monoclonal antibodies against Iba- 1 antigen. The results have shown that the reaction of microglia to acute hypoxia in both the neocortex and the hippocampus of the new-borns developed simultaneously and synchronously with the augmentation of cell death. The increase of a population density of amoeboid form of microglial cells in the brain areas studied was recorded already after 1 hour as a result of their migration from the subventricular region and the areas adjacent to large vessels from where they practically disappeared. The number of amoeboid microglial cells in this area has recovered rather quickly (in 3 hrs). The population densify of microglial cells, especially of amoeboid forms, sharply increased with the augmentation of cell death and remained unchanged for about 5 days.

  9. Role of carbon monoxide in impaired endothelial function mediated by acute second-hand tobacco, incense, and candle smoke exposures.

    Science.gov (United States)

    Weber, Lynn P; Al-Dissi, Ahmad; Marit, Jordan S; German, Timothy N; Terletski, Sharilyn D

    2011-05-01

    The aim of this study was to determine if carbon monoxide (CO) is responsible for acute adverse cardiovascular effects of different sources of smoke: second-hand tobacco smoke (SHS), incense and candle smoke. Endothelial function was tested using flow-mediated dilation (FMD) in pigs and was shown to be sensitive to nitric oxide synthase blockade. Subsequent experiments showed that FMD was significantly impaired compared to sham-exposed pigs at 30 min after a 30-min exposure to all three sources of smoke. In contrast, SHS significantly increased systolic, diastolic and pulse pressures compared to sham-exposure, while both incense and candle smoke exposure had no effect. The FMD impairment correlated well with CO levels in the exposure chamber, but not total particulates or venous CO-hemoglobin. Therefore, this study suggests a gas phase component of smoke that accompanies CO, but not CO itself, is responsible for acute endothelial dysfunction after SHS, incense or candle smoke exposure.

  10. Acute exposure to apolipoprotein A1 inhibits macrophage chemotaxis in vitro and monocyte recruitment in vivo

    Science.gov (United States)

    Iqbal, Asif J; Barrett, Tessa J; Taylor, Lewis; McNeill, Eileen; Manmadhan, Arun; Recio, Carlota; Carmineri, Alfredo; Brodermann, Maximillian H; White, Gemma E; Cooper, Dianne; DiDonato, Joseph A; Zamanian-Daryoush, Maryam; Hazen, Stanley L; Channon, Keith M

    2016-01-01

    Apolipoprotein A1 (apoA1) is the major protein component of high-density lipoprotein (HDL) and has well documented anti-inflammatory properties. To better understand the cellular and molecular basis of the anti-inflammatory actions of apoA1, we explored the effect of acute human apoA1 exposure on the migratory capacity of monocyte-derived cells in vitro and in vivo. Acute (20–60 min) apoA1 treatment induced a substantial (50–90%) reduction in macrophage chemotaxis to a range of chemoattractants. This acute treatment was anti-inflammatory in vivo as shown by pre-treatment of monocytes prior to adoptive transfer into an on-going murine peritonitis model. We find that apoA1 rapidly disrupts membrane lipid rafts, and as a consequence, dampens the PI3K/Akt signalling pathway that coordinates reorganization of the actin cytoskeleton and cell migration. Our data strengthen the evidence base for therapeutic apoA1 infusions in situations where reduced monocyte recruitment to sites of inflammation could have beneficial outcomes. DOI: http://dx.doi.org/10.7554/eLife.15190.001 PMID:27572261

  11. [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.

  12. Acute inhalation toxicity evaluation of a 93:7 mixture of perfluoro-2-butene and 1-bromopropane, a replacement candidate for ozone depleting substances. Interim report, July--August 1997

    Energy Technology Data Exchange (ETDEWEB)

    Feldmann, M.L.; Leahy, H.F.; Vinegar, A.

    1997-10-01

    The DoD requires the development of toxicity profiles for chemical substitute candidates proposed to replace ozone depleting substances such as chloro- and fluorocarbons and halons. A 93:7 mixture of perfluoro-2-butene and 1-bromopropane was identified as a possible replacement candidate for ozone-depleting fire extinguishants. An acute inhalation toxicity test utilizing male and female Fischer 344 rats was performed on this test material. No deaths occurred in any of the rats exposed to 5.3 mg/L of the 93:7 perfluoro-2-butene and 1-bromopropane mixture. Body weights of male and female rats during the subsequent 14-day observation period were unaffected by treatment. The test material did not produce acute toxicity via the inhalation route.

  13. Sustained impairment of respiratory function and swim performance following acute oil exposure in a coastal marine fish.

    Science.gov (United States)

    Johansen, J L; Esbaugh, A J

    2017-06-01

    Acute exposure to crude oil polycyclic aromatic hydrocarbons (PAH) can severely impair cardiorespiratory function and swim performance of larval fish; however, the effects of acute oil exposure on later life stages and the capacity for subsequent recovery is less clear. Red drum (Sciaenops ocellatus) is an economically important apex predator native to the Gulf of Mexico, which was directly exposed to the 2010 Deep Water Horizon (DWH) oil spill. Here we examine impact and recovery of young adult red drum from exposure to concentrations of 0, 4.1, and 12.1μgL(-1) ΣPAH50 naturally weathered oil-water accommodated fractions (geometric mean), which are well within the range of concentrations measured during the DWH incident. We focused on aerobic scope (ASc), burst- and critical swimming speeds (Uburst and Ucrit), cost of transport (COT), as well as the capacity to repay oxygen debt following exhaustive exercise (EPOC), which are critical parameters for success of all life stages of fishes. A 24h acute exposure to 4.1μgL(-1) ΣPAH caused a significant 9.7 and 12.6% reduction of Uburst and Ucrit respectively, but no change in ASc, COT or EPOC, highlighting a decoupled effect on the respiratory and swimming systems. A higher exposure concentration, 12.1μgL(-1) ΣPAH, caused an 8.6 and 8.4% impairment of Uburst and Ucrit, as well as an 18.4% reduction in ASc. These impairments persisted six weeks post-exposure, suggesting that recorded impacts are entrenched. Large predatory fishes are critically dependent on the cardiorespiratory and swimming systems for ecological fitness, and long-term impairment of performance due to acute oil exposure suggests that even acute exposure events may have long lasting impacts on the ecological fitness of affected populations. Copyright © 2017. Published by Elsevier B.V.

  14. Carryover Effects of Acute DEHP Exposure on Ovarian Function and Oocyte Developmental Competence in Lactating Cows.

    Science.gov (United States)

    Kalo, Dorit; Hadas, Ron; Furman, Ori; Ben-Ari, Julius; Maor, Yehoshua; Patterson, Donald G; Tomey, Cynthia; Roth, Zvi

    2015-01-01

    We examined acute exposure of Holstein cows to di(2-ethylhexyl) phthalate (DEHP) and its carryover effects on ovarian function and oocyte developmental competence. Synchronized cows were tube-fed with water or 100 mg/kg DEHP per day for 3 days. Blood, urine and milk samples were collected before, during and after DEHP exposure to examine its clearance pattern. Ovarian follicular dynamics was monitored through an entire estrous cycle by ultrasonographic scanning. Follicular fluids were aspirated from the preovulatory follicles on days 0 and 29 of the experiment and analyzed for phthalate metabolites and estradiol concentration. The aspirated follicular fluid was used as maturation medium for in-vitro embryo production. Findings revealed that DEHP impairs the pattern of follicular development, with a prominent effect on dominant follicles. The diameter and growth rate of the first- and second-wave dominant follicles were lower (P 25 mm). The pattern of growth and regression of the corpus luteum differed between groups, with a lower volume in the DEHP-treated group (P < 0.05). The follicular fluid aspirated from the DEHP-treated group, but not the controls, contained 23 nM mono(2-ethylhexyl) phthalate. Culturing of cumulus oocyte complexes in the follicular fluid aspirated from DEHP-treated cows reduced the proportion of oocytes progressing to the MII stage, and the proportions of 2- to 4-cell-stage embryos (P < 0.04) and 7-day blastocysts (P < 0.06). The results describe the risk associated with acute exposure to DEHP and its deleterious carryover effects on ovarian function, nuclear maturation and oocyte developmental competence.

  15. Carryover Effects of Acute DEHP Exposure on Ovarian Function and Oocyte Developmental Competence in Lactating Cows

    Science.gov (United States)

    Kalo, Dorit; Hadas, Ron; Furman, Ori; Ben-Ari, Julius; Maor, Yehoshua; Patterson, Donald G.; Tomey, Cynthia; Roth, Zvi

    2015-01-01

    We examined acute exposure of Holstein cows to di(2-ethylhexyl) phthalate (DEHP) and its carryover effects on ovarian function and oocyte developmental competence. Synchronized cows were tube-fed with water or 100 mg/kg DEHP per day for 3 days. Blood, urine and milk samples were collected before, during and after DEHP exposure to examine its clearance pattern. Ovarian follicular dynamics was monitored through an entire estrous cycle by ultrasonographic scanning. Follicular fluids were aspirated from the preovulatory follicles on days 0 and 29 of the experiment and analyzed for phthalate metabolites and estradiol concentration. The aspirated follicular fluid was used as maturation medium for in-vitro embryo production. Findings revealed that DEHP impairs the pattern of follicular development, with a prominent effect on dominant follicles. The diameter and growth rate of the first- and second-wave dominant follicles were lower (P 25 mm). The pattern of growth and regression of the corpus luteum differed between groups, with a lower volume in the DEHP-treated group (P < 0.05). The follicular fluid aspirated from the DEHP-treated group, but not the controls, contained 23 nM mono(2-ethylhexyl) phthalate. Culturing of cumulus oocyte complexes in the follicular fluid aspirated from DEHP-treated cows reduced the proportion of oocytes progressing to the MII stage, and the proportions of 2- to 4-cell-stage embryos (P < 0.04) and 7-day blastocysts (P < 0.06). The results describe the risk associated with acute exposure to DEHP and its deleterious carryover effects on ovarian function, nuclear maturation and oocyte developmental competence. PMID:26154164

  16. Carryover Effects of Acute DEHP Exposure on Ovarian Function and Oocyte Developmental Competence in Lactating Cows.

    Directory of Open Access Journals (Sweden)

    Dorit Kalo

    Full Text Available We examined acute exposure of Holstein cows to di(2-ethylhexyl phthalate (DEHP and its carryover effects on ovarian function and oocyte developmental competence. Synchronized cows were tube-fed with water or 100 mg/kg DEHP per day for 3 days. Blood, urine and milk samples were collected before, during and after DEHP exposure to examine its clearance pattern. Ovarian follicular dynamics was monitored through an entire estrous cycle by ultrasonographic scanning. Follicular fluids were aspirated from the preovulatory follicles on days 0 and 29 of the experiment and analyzed for phthalate metabolites and estradiol concentration. The aspirated follicular fluid was used as maturation medium for in-vitro embryo production. Findings revealed that DEHP impairs the pattern of follicular development, with a prominent effect on dominant follicles. The diameter and growth rate of the first- and second-wave dominant follicles were lower (P 25 mm. The pattern of growth and regression of the corpus luteum differed between groups, with a lower volume in the DEHP-treated group (P < 0.05. The follicular fluid aspirated from the DEHP-treated group, but not the controls, contained 23 nM mono(2-ethylhexyl phthalate. Culturing of cumulus oocyte complexes in the follicular fluid aspirated from DEHP-treated cows reduced the proportion of oocytes progressing to the MII stage, and the proportions of 2- to 4-cell-stage embryos (P < 0.04 and 7-day blastocysts (P < 0.06. The results describe the risk associated with acute exposure to DEHP and its deleterious carryover effects on ovarian function, nuclear maturation and oocyte developmental competence.

  17. Anticholinergic drug exposure is associated with delirium and postdischarge institutionalization in acutely ill hospitalized older patients.

    Science.gov (United States)

    Egberts, Angelique; van der Craats, Saskia T; van Wijk, Melissa D; Alkilabe, Shams; van den Bemt, Patricia M L A; Mattace-Raso, Francesco U S

    2017-06-01

    Several studies investigated the possible association between anticholinergic drugs and diverse clinical outcomes in older persons, but the results are inconsistent. The aim of this study was to investigate whether anticholinergic drug exposure is associated with delirium on admission, length of hospital stay, postdischarge institutionalization and in-hospital mortality in acutely ill hospitalized older patients. In this observational chart review study, we included acutely ill patients aged 65 and older who were admitted to the geriatric ward of the Erasmus University Medical Center, Rotterdam, The Netherlands, between 2012 and 2015 (n = 905). Anticholinergic drug exposure on admission was defined as the use of anticholinergic drugs, total number of anticholinergic drugs and anticholinergic drug burden score (ADB), quantified with the Anticholinergic Risk Scale (ARS), the Anticholinergic Cognitive Burden scale (ACB) and the list of Chew et al. (Chew). Logistic regression analyses were performed to investigate possible associations between anticholinergic drug exposure and the aforementioned outcomes. Analyses were adjusted for age, sex, comorbidities, non-anticholinergic drugs and delirium, where appropriate. Moderate and high ADB measured with the ARS were associated with delirium on admission with odds ratios (OR) of 1.70 (95% confidence interval (CI) = 1.16-2.49) and 1.83 (95% CI = 1.06-3.15), respectively. High ADB measured with the ARS was also associated with postdischarge institutionalization (OR = 2.43, 95% CI = 1.24-4.75). No associations were found using the ACB and Chew. Future studies are warranted to investigate the clinical usefulness of the ARS in reducing complications in older persons.

  18. Nitrogen soil emissions and belowground plant processes in Mediterranean annual pastures are altered by ozone exposure and N-inputs

    Science.gov (United States)

    Sánchez-Martín, L.; Bermejo-Bermejo, V.; García-Torres, L.; Alonso, R.; de la Cruz, A.; Calvete-Sogo, H.; Vallejo, A.

    2017-09-01

    Increasing tropospheric ozone (O3) and atmospheric nitrogen (N) deposition alter the structure and composition of pastures. These changes could affect N and C compounds in the soil that in turn can influence soil microbial activity and processes involved in the emission of N oxides, methane (CH4) and carbon dioxide (CO2), but these effects have been scarcely studied. Through an open top chamber (OTC) field experiment, the combined effects of both pollutants on soil gas emissions from an annual experimental Mediterranean community were assessed. Four O3 treatments and three different N input levels were considered. Fluxes of nitric (NO) and nitrous (N2O) oxide, CH4 and CO2 were analysed as well as soil mineral N and dissolved organic carbon. Belowground plant parameters like root biomass and root C and N content were also sampled. Ozone strongly increased soil N2O emissions, doubling the cumulative emission through the growing cycle in the highest O3 treatment, while N-inputs enhanced more slightly NO; CH4 and CO2 where not affected. Both N-gases had a clear seasonality, peaking at the start and at the end of the season when pasture physiological activity is minimal; thus, higher microorganism activity occurred when pasture had a low nutrient demand. The O3-induced peak of N2O under low N availability at the end of the growing season was counterbalanced by the high N inputs. These effects were related to the O3 x N significant interaction found for the root-N content in the grass and the enhanced senescence of the community. Results indicate the importance of the belowground processes, where competition between plants and microorganisms for the available soil N is a key factor, for understanding the ecosystem responses to O3 and N.

  19. Assessment of locomotion behavior in adult Zebrafish after acute exposure to different pharmacological reference compounds

    Directory of Open Access Journals (Sweden)

    Pankaj Gupta

    2014-01-01

    Full Text Available Objectives: The objective of the present study was to assess locomotor behavior of adult zebrafish after acute exposure to different pharmacological reference compounds. Materials and Methods: Adult zebrafish of 4-5-months-old were exposed to different concentrations of known reference compounds for 15 min. The test was conducted separately for each drug concentration as well as control. Locomotor activity parameters viz. distance travelled, speed, total mobile time, and total immobile time were recorded for each animal during the exposure period. Results: Out of 11 compounds tested, nine compounds showed decrease in locomotor behavior with significant changes in distance travelled, speed, total mobile time, and total immobile time. Caffeine exhibited biphasic response in locomotion behavior, while scopolamine failed to induce any significant changes. Conclusion: In view of the above findings, these results suggested that exposure of adult zebrafish with different known compounds produce the expected changes in the locomotion behavior; therefore, adult zebrafish can be used an alternative approach for the assessment of new chemical entities for their effect on locomotor behavior.

  20. Setting safe acute exposure limits for halon replacement chemicals using physiologically based pharmacokinetic modeling.

    Science.gov (United States)

    Vinegar, A; Jepson, G W; Cisneros, M; Rubenstein, R; Brock, W J

    2000-08-01

    Most proposed replacements for Halon 1301 as a fire suppressant are halogenated hydrocarbons. The acute toxic endpoint of concern for these agents is cardiac sensitization. An approach is described that links the cardiac endpoint as assessed in dogs to a target arterial concentration in humans. Linkage was made using a physiologically based pharmacokinetic (PBPK) model. Monte Carlo simulations, which account for population variability, were used to establish safe exposure times at different exposure concentrations for Halon 1301 (bromotrifluoromethane), CF(3)I (trifluoroiodomethane), HFC-125 (pentafluoroethane), HFC-227ea (1,1,1,2,3,3,3-heptafluoropropane), and HFC-236fa (1,1,1,3,3,3-hexafluoropropane). Application of the modeling technique described here not only makes use of the conservative cardiac sensitization endpoint, but also uses an understanding of the pharmacokinetics of the chemical agents to better establish standards for safe exposure. The combined application of cardiac sensitization data and physiologically based modeling provides a quantitative approach, which can facilitate the selection and effective use of halon replacement candidates.

  1. Global Crop Yield Reductions due to Surface Ozone Exposure: Crop Production Losses and Economic Damage in 2000 and 2030 under Two Future Scenarios of O3 Pollution

    Science.gov (United States)

    Avnery, S.; Mauzerall, D. L.; Liu, J.; Horowitz, L. W.

    2011-12-01

    Field studies demonstrate that exposure to elevated concentrations of surface ozone (O3) may cause substantial reductions in the agricultural yields of many crops. As emissions of O3 precursors rise in many parts of the world over the next few decades, yield reductions from O3 exposure may increase the challenges of feeding a global population projected to grow from approximately 6 to 8 billion people between 2000 and 2030. This study estimates global yield reductions of three key staple crops (soybean, maize, and wheat) due to surface ozone exposure in 2000 and 2030 according to two trajectories of O3 pollution: the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios (IPCC SRES) A2 and B1 storylines, which represent upper- and lower-boundary projections, respectively, of most O3 precursor emissions in 2030. Our results indicate that year 2000 O3-induced global yield reductions ranged, depending on the O3 exposure metric used, from 3.9-15% for wheat, 8.5-14% for soybean, and 2.2-5.5% for maize. Global crop production losses totaled 79-121 million metric tons, worth 11-18 billion annually (USD2000). In the 2030-A2 scenario we find global O3-induced yield loss of wheat to be 5.4-26% (a further reduction in yield of +1.5-10% from year 2000 values), 15-19% for soybean (reduction of +0.9-11%), and 4.4-8.7% for maize (reduction of +2.1-3.2%) depending on the metric used, with total global agricultural losses worth 17-35 billion USD2000 annually (an increase of +6-17 billion in losses from 2000). Under the 2030-B1 scenario, we project less severe but still substantial reductions in yields: 4.0-17% for wheat (a further decrease in yield of +0.1-1.8% from 2000), 9.5-15% for soybean (decrease of +0.7-1.0%), and 2.5-6.0% for maize (decrease of+ 0.3-0.5%), with total losses worth 12-21 billion annually (an increase of +$1-3 billion in losses from 2000). Because our analysis uses crop data from the year 2000, which likely underestimates agricultural

  2. Responses of human health and vegetation exposure metrics to changes in ozone concentration distributions in the European Union, United States, and China

    Science.gov (United States)

    Lefohn, Allen S.; Malley, Christopher S.; Simon, Heather; Wells, Benjamin; Xu, Xiaobin; Zhang, Li; Wang, Tao

    2017-03-01

    The impacts of surface ozone (O3) on human health and vegetation have prompted O3 precursor emission reductions in the European Union (EU) and United States (US). In contrast, until recently, emissions have increased in East Asia and most strongly in China. As emissions change, the distribution of hourly O3 concentrations also changes, as do the values of exposure metrics. The distribution changes can result in the exposure metric trend patterns changing in a similar direction as trends in emissions (e.g., metrics increase as emissions increase) or, in some cases, in opposite directions. This study, using data from 481 sites (276 in the EU, 196 in the US, and 9 in China), investigates the response of 14 human health and vegetation O3 exposure metrics to changes in hourly O3 concentration distributions over time. At a majority of EU and US sites, there was a reduction in the frequency of both relatively high and low hourly average O3 concentrations. In contrast, for some sites in mainland China and Hong Kong, the middle of the distribution shifted upwards but the low end did not change and for other sites, the entire distribution shifted upwards. The responses of the 14 metrics to these changes at the EU, US, and Chinese sites were varied, and dependent on (1) the extent to which the metric was determined by relatively high, moderate, and low concentrations and (2) the relative magnitude of the shifts occurring within the O3 concentration distribution. For example, the majority of the EU and US sites experienced decreasing trends in the magnitude of those metrics associated with higher concentrations. For the sites in China, all of the metrics either increased or had no trends. In contrast, there were a greater number of sites that had no trend for those metrics determined by a combination of moderate and high O3 concentrations. A result of our analyses is that trends in mean or median concentrations did not appear to be well associated with some exposure metrics

  3. ACUTE NEUROTOXIC EFFECTS OF INHALED PERCHLOROETHYLENE ON PATTERN VISUAL EVOKED POTENTIALS AS A FUNCTION OF EXPOSURE AND ESTIMATED BLOOD AND BRAIN CONCENTRATION.

    Science.gov (United States)

    Previous experiments have shown the effects of acute inhalation exposure to trichloroethylene (TCE) and toluene are related to the target tissue concentration at the time of testing. The current studies examined exposure to another volatile organic compound, perchloroethylene (P...

  4. ACUTE NEUROTOXIC EFFECTS OF INHALED PERCHLOROETHYLENE ON PATTERN VISUAL EVOKED POTENTIALS AS A FUNCTION OF EXPOSURE AND ESTIMATED BLOOD AND BRAIN CONCENTRATION.

    Science.gov (United States)

    Previous experiments have shown the effects of acute inhalation exposure to trichloroethylene (TCE) and toluene are related to the target tissue concentration at the time of testing. The current studies examined exposure to another volatile organic compound, perchloroethylene (P...

  5. Ozone Reductions Using Residential Building Envelopes

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain S.; Sherman, Max; Nazaroff, William W.

    2009-02-01

    Ozone is an air pollutant with that can have significant health effects and a significant source of ozone in some regions of California is outdoor air. Because people spend the vast majority of their time indoors, reduction in indoor levels of ozone could lead to improved health for many California residents. Ozone is removed from indoor air by surface reactions and can also be filtered by building envelopes. The magnitude of the envelope impact depends on the specific building materials that the air flows over and the geometry of the air flow paths through the envelope that can be changes by mechanical ventilation operation. The 2008 Residential Building Standards in California include minimum requirements for mechanical ventilation by referencing ASHRAE Standard 62.2. This study examines the changes in indoor ozone depending on the mechanical ventilation system selected to meet these requirements. This study used detailed simulations of ventilation in a house to examine the impacts of different ventilation systems on indoor ozone concentrations. The simulation results showed that staying indoors reduces exposure to ozone by 80percent to 90percent, that exhaust ventilation systems lead to lower indoor ozone concentrations, that opening of windows should be avoided at times of high outdoor ozone, and that changing the time at which mechanical ventilation occurs has the ability to halve exposure to ozone. Future work should focus on the products of ozone reactions in the building envelope and the fate of these products with respect to indoor exposures.

  6. The body weight loss during acute exposure to high-altitude hypoxia in sea level residents.

    Science.gov (United States)

    Ge, Ri-Li; Wood, Helen; Yang, Hui-Huang; Liu, Yi-Ning; Wang, Xiu-Juan; Babb, Tony

    2010-12-25

    Weight loss is frequently observed after acute exposure to high altitude. However, the magnitude and rate of weight loss during acute exposure to high altitude has not been clarified in a controlled prospective study. The present study was performed to evaluate weight loss at high altitude. A group of 120 male subjects [aged (32±6) years] who worked on the construction of the Golmud-Lhasa Railway at Kunlun Mountain (altitude of 4 678 m) served as volunteer subjects for this study. Eighty-five workers normally resided at sea level (sea level group) and 35 normally resided at an altitude of 2 200 m (moderate altitude group). Body weight, body mass index (BMI), and waist circumference were measured in all subjects after a 7-day stay at Golmud (altitude of 2 800 m, baseline measurements). Measurements were repeated after 33-day working on Kunlun Mountain. In order to examine the daily rate of weight loss at high altitude, body weight was measured in 20 subjects from the sea level group (sea level subset group) each morning before breakfast for 33 d at Kunlun Mountain. According to guidelines established by the Lake Louise acute mountain sickness (AMS) consensus report, each subject completed an AMS self-report questionnaire two days after arriving at Kunlun Mountain. After 33-day stay at an altitude of 4 678 m, the average weight loss for the sea level group was 10.4% (range 6.5% to 29%), while the average for the moderate altitude group was 2.2% (-2% to 9.1%). The degree of weight loss (Δ weight loss) after a 33-day stay at an altitude of 4 678 m was significantly correlated with baseline body weight in the sea level group (r=0.677, P0.05). In the sea level subset group, a significant weight loss was observed within 20 d, but the weight remained stable thereafter. AMS-score at high altitude was significantly higher in the sea level group (4.69±2.48) than that in the moderate altitude group (2.97±1.38), and was significantly correlated with baseline body weight

  7. A case of acute psychosis in a patient following exposure to a single high dose of styrene.

    Science.gov (United States)

    Moon, Eunsoo; Suh, Hwagyu; Lee, Byung Dae; Park, Je Min; Lee, Young Min; Jeong, Hee Jeong

    2015-09-01

    We report a case of acute psychotic symptoms following exposure to a single high dose of styrene monomer. The 24-year-old male patient showed psychotic and cognitive symptoms immediately after exposure. His psychotic symptoms included auditory hallucinations and delusions of reference. Brain magnetic resonance imaging, electroencephalography, and laboratory examinations were performed to evaluate any other causes. The clinical, neuroimaging, and laboratory review in this case suggested that the suddenly developed psychotic symptoms that led to chronic deterioration were caused by the single exposure to styrene monomer. This is the first recent report in which acute psychotic symptoms developed from a single high dose of styrene suffocation compared with previous findings showing symptoms because of long-term low-dose exposure.

  8. Absence of acute ocular damage in humans after prolonged exposure to intense RF EMF

    Science.gov (United States)

    Adibzadeh, F.; van Rhoon, G. C.; Verduijn, G. M.; Naus-Postema, N. C.; Paulides, M. M.

    2016-01-01

    The eye is considered to be a critical organ when determining safety standards for radio frequency (RF) radiation. Experimental data obtained using animals showed that RF heating of the eye, particularly over a specific threshold, can induce cataracts. During the treatment of cancer in the head and neck by hyperthermia, the eyes receive a considerable dose of RF radiation due to stray radiation from the prolonged (60 min) and intense exposure at 434 MHz of this region. In the current study, we verified the exposure guidelines for humans by determining the association between the electromagnetic and thermal dose in the eyes with the reported ocular effects. We performed a simulation study to retrospectively assess the specific absorption rate (SAR) and temperature increase in the eyes of 16 selected patients (encompassing a total of 74 treatment sessions) whose treatment involved high power delivery as well as a minimal distance between the tumor site and the eye. Our results show that the basic restrictions on the peak 10 g spatial-averaged SAR (10 W kg-1) and peak tissue temperature increase (1 °C) are exceeded by up to 10.4 and 4.6 times, on average, and by at least 6.2 and 1.8 times when considering the lower limit of the 95% confidence interval. Evaluation of the acute effects according to patients’ feedback (all patients), the common toxicity criteria scores (all patients) and an ophthalmology investigation (one patient with the highest exposure) revealed no indication of any serious acute ocular effect, even though the eyes were exposed to high electromagnetic fields, leading to a high thermal dose. We also found that, although there is a strong correlation (R 2  =  0.88) between the predicted induced SAR and temperature in the eye, there are large uncertainties regarding the temperature-SAR relationship. Given this large uncertainty (129%) compared with the uncertainty of 3D temperature simulations (61%), we recommend using temperature

  9. Effect of low doses of lipopolysaccharide prior to ozone exposure οn bronchoalveolar lavage. Differences between wild type and surfactant protein A-deficient mice

    Directory of Open Access Journals (Sweden)

    Rizwanul Haque

    2009-01-01

    Full Text Available SUMMARY. BACKGROUND: Several aspects of the inflammatory response to a single insult, i.e., exposure to 2 ppm of ozone (O3 for 3 h or 6 h, are less pronounced in surfactant protein A deficient (SP-A -/- mice (KO than in wild type mice (WT. It was hypothesized that a mild insult, specifically low doses of lipopolysaccharide (LPS, would adversely affect host defense and differentially potentiate O3-induced injury in WT and KO mice. METHODS: WT and KO mice were treated with different doses of LPS or LPS (2 ng + O3 (2 ppm or filtered air (FA for 3 h, then sacrificed 4 h following exposure (O3, FA or 20 h after LPS treatment alone. Several endpoints of inflammation were measured in bronchoalveolar lavage (BAL. RESULTS: 1 At 20 h after LPS treatment alone, both WT and KO mice exhibited signs of inflammation, but with differences in the macrophage inflammatory protein 2 (MIP-2 response pattern, total cells (at 0.5 ng LPS and basal levels of oxidized protein and phospholipids; 2 After LPS + O3, KO compared to WT showed decrease in polymorphonuclear leukocytes (PMNs and MIP-2 and increase in phospholipids, and after LPS + FA an increase in total cells; 3 WT after LPS + FA showed an increase in SP-A with no further increase after LPS + O3, and an increase in oxidized SP-A dimer following O3 or LPS + O3. CONCLUSIONS: LPS treatment has negative effects on inflammation endpoints in mouse BAL long after exposure and renders KO mice less capable of responding to a second insult. LPS and O3 affect SP-A, quantitatively and qualitatively, respectively. Pneumon 2009; 22(2:131–155.

  10. Comprehensive analysis of the renal transcriptional response to acute uranyl nitrate exposure

    Directory of Open Access Journals (Sweden)

    Argiles Angel

    2006-01-01

    Full Text Available Abstract Background Chemical and radiological toxicities related to uranium acute exposure have been widely studied in nuclear fuel workers and military personnel. It is well known that uranyl nitrate induces acute renal failure (ARF. However, the mechanisms of this metal-induced injury are not well defined at the molecular level. Results Renal function and histology were assessed in mice receiving uranyl nitrate (UN(+ and controls (UN(-. To identify the genomic response to uranium exposure, serial analysis gene expression (SAGE of the kidney was performed in both groups. Over 43,000 mRNA SAGE tags were sequenced. A selection of the differentially expressed transcripts was confirmed by real-time quantitative PCR and Western blotting. UN(+ animals developed renal failure and displayed the characteristic histological lesions of UN nephropathy. Of the >14,500 unique tags identified in both libraries, 224 had a modified expression level; they are known to participate in inflammation, ion transport, signal transduction, oxidative stress, apoptosis, metabolism, and catabolism. Several genes that were identified had not previously been evaluated within the context of toxic ARF such as translationally controlled tumor protein, insulin like growth factor binding protein 7 and ribosomal protein S29, all apoptosis related genes. Conclusion We report a comprehensive description of the UN induced modifications in gene expression levels, including the identification of genes previously unrelated to ARF. The study of these genes and the metabolisms they control should improve our understanding of toxic ARF and enlighten on the molecular targets for potential therapeutic interventions.

  11. 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...

  12. Effect of zinc sacrificial anode degradation on the defence system of the Pacific oyster, Crassostrea gigas: chronic and acute exposures.

    Science.gov (United States)

    Mottin, Elmina; Caplat, Christelle; Latire, Thomas; Mottier, Antoine; Mahaut, Marie-Laure; Costil, Katherine; Barillier, Daniel; Lebel, Jean-Marc; Serpentini, Antoine

    2012-09-01

    Two types of exposures were performed to assess the effects of zinc released from sacrificial anode degradation: a chronic exposure, in which oysters were exposed to 0.53±0.04 mg Zn L(-1) for 10 weeks, and an acute exposure, where oysters were exposed to 10.2±1.2 mg Zn L(-1) for 1 week. At the end of the acute exposure experiment, 81.8% mortality was recorded. In contrast, no mortality was detected after 10 weeks exposure. Moreover, all of the immune system biomarkers studied, except the number of circulating haemocytes, were stimulated by a moderate level of zinc and inhibited by a high level. Our exposure conditions did not induce SOD or MXR mRNA expression in gills and digestive gland. However, an increase of MT mRNA is observed in these tissues. The results indicate that oysters are sensitive to acute zinc toxicity but are only moderately affected by a mild zinc concentration.

  13. Maternal metallothionein and zinc after acute ethanol exposure during gestation in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Harris, J.E. (Univ. of Kansas, Kansas City (United States))

    1992-02-26

    Acute exposure of the rat fetus to ethanol at critical periods can cause growth retardation and brain damage; the mechanism(s) is not known. Ethanol may cause redistribution of maternal zinc which results in fetal zinc deficiency and subsequent interruption of growth and development. The purpose was to determine if acute ethanol administration to the pregnant rat alters Zn and the Zn binding protein metallothionein (MT) in selected tissues. On gestational day (gd) 14, eighteen pregnant Sprague-Dawley rats were divided into groups. By intragastric tube, ethanol treated dams were given ethanol and pairfed controls were given a 0.85% NaCl solution. On gd 15, intragastric feedings were repeated. Throughout, the Lieber-DeCarli control diet was fed (adlibitum to untreated controls and ethanol treated dams and in appropriate quantities to pair fed controls). Blood ethanol concentrations at 90 minutes after the ethanol dose were 154 {plus minus} 46 and 265 {plus minus} 110 mg% on gd 14 and 15, respectively.

  14. Noninvasive Biomonitoring Approaches to Determine Dosimetry and Risk Following Acute Chemical Exposure: Analysis of Lead or Organophosphate Insecticide in Saliva

    Energy Technology Data Exchange (ETDEWEB)

    Timchalk, Chuck; Poet, Torka S.; Kousba, Ahmed A.; Campbell, James A.; Lin, Yuehe

    2004-04-01

    There is a need to develop approaches for assessing risk associated with acute exposures to a broad-range of chemical agents and to rapidly determine the potential implications to human health. Non-invasive biomonitoring approaches are being developed using reliable portable analytical systems to quantitate dosimetry utilizing readily obtainable body fluids, such as saliva. Saliva has been used to evaluate a broad range of biomarkers, drugs, and environmental contaminants including heavy metals and pesticides. To advance the application of non-invasive biomonitoring a microfluidic/ electrochemical device has also been developed for the analysis of lead (Pb), using square wave anodic stripping voltammetry. The system demonstrates a linear response over a broad concentration range (1 2000 ppb) and is capable of quantitating saliva Pb in rats orally administered acute doses of Pb-acetate. Appropriate pharmacokinetic analyses have been used to quantitate systemic dosimetry based on determination of saliva Pb concentrations. In addition, saliva has recently been used to quantitate dosimetry following exposure to the organophosphate insecticide chlorpyrifos in a rodent model system by measuring the major metabolite, trichloropyridinol, and saliva cholinesterase inhibition following acute exposures. These results suggest that technology developed for non-invasive biomonitoring can provide a sensitive, and portable analytical tool capable of assessing exposure and risk in real-time. By coupling these non-invasive technologies with pharmacokinetic modeling it is feasible to rapidly quantitate acute exposure to a broad range of chemical agents. In summary, it is envisioned that once fully developed, these monitoring and modeling approaches will be useful for accessing acute exposure and health risk.

  15. [Effect of training on treadmill performance, aerobic capacity and body reactions to acute cold exposure].

    Science.gov (United States)

    Iakushkin, A V; Akimov, E B; Andreev, R S; Kalenov, Iu N; Kozlov, A V; Kuznetsova, O V; Son'kin, V D

    2014-01-01

    An attempt was made to test the hypothesis that regular physical activity at the anaerobic threshold is able to stimulate an increase in the amount of body fat brown or beige, which can manifest itself in increasing lactate utilization during exercise and increase the reactivity in response to acute regional cooling. The methods used are: ramp test, regional acute cold exposure, measurement of gas exchange, lactate and glucose in the blood, heart rate, and heart rate variability, blood pressure and respiration variability at rest and during standard functional tests; infrared thermal imaging, statistical methods of results analysis. Workout 10 physically active volunteers (7 males and 3 females) on a treadmill at a speed corresponding to 75-80% of the persona VO2max for 30 minutes 3 times per week at a fixed ambient temperature 21-22°C for 6 weeks resulted in a significant (from 19 to 39%) increase in test work duration but VO2max on average changed little. The increase in power of anaerobic threshold was associated with a sharp slowdown in the accumulation of lactate in progress of ramp test. Lactate utilization rate during the recovery period, on the contrary, increased. In general, significantly increased work efficiency at a test load. Not revealed noticeable changes in the condition and response to a standard functional tests of autonomic systems, as judged by heart rate variability, blood pressure and respiration variability at rest and during orthostatic tests and imposed breathing rhythm. The functional response of the body to acute cold exposure (1 minute cooling of the feet in ice water) is not changed after a cycle of training--either in terms of metabolism (oxygen consumption, etc.), or the dynamics of the skin temperature in areas of most probable location of brown adipose tissue (BAT). These data do not confirm the previously expressed (2010) hypothesis about the function of BAT as a universal homeostatic instrument in the body. Probably, if under

  16. Acute vertigo in an anesthesia provider during exposure to a 3T MRI scanner

    Directory of Open Access Journals (Sweden)

    Gorlin A

    2015-03-01

    Full Text Available Andrew Gorlin,1 Joseph M Hoxworth,2 William Pavlicek,2 Christopher A Thunberg,1 David Seamans1 1Department of Anesthesiology, 2Department of Radiology, Mayo Clinic Arizona, Phoenix, AZ, USA Abstract: Vertigo induced by exposure to the magnetic field of a magnetic resonance imaging (MRI scanner is a well-known phenomenon within the radiology community but is not widely appreciated by other clinical specialists. Here, we describe a case of an anesthetist experiencing acute vertigo while providing sedation to a patient undergoing a 3 Tesla MRI scan. After discussing previous reports, and the evidence surrounding MRI-induced vertigo, we review potential etiologies that include the effects of both static and time-varying magnetic fields on the vestibular apparatus. We conclude our review by discussing the occupational standards that exist for MRI exposure and methods to minimize the risks of MRI-induced vertigo for clinicians working in the MRI environment. Keywords: occupational medicine, MRI worker safety, vestibular dysfunction, magnetic field, 3T MRI scanner

  17. Acute Exposure to Stress Improves Performance in Trace Eyeblink Conditioning and Spatial Learning Tasks in Healthy Men

    Science.gov (United States)

    Duncko, Roman; Cornwell, Brian; Cui, Lihong; Merikangas, Kathleen R.; Grillon, Christian

    2007-01-01

    The present study investigated the effects of acute stress exposure on learning performance in humans using analogs of two paradigms frequently used in animals. Healthy male participants were exposed to the cold pressor test (CPT) procedure, i.e., insertion of the dominant hand into ice water for 60 sec. Following the CPT or the control procedure,…

  18. Performance, acute health symptoms and physiological responses during exposure to high air temperature and carbon dioxide concentration

    DEFF Research Database (Denmark)

    liu, weiwei; Zhong, Weidi; Wargocki, Pawel

    2017-01-01

    subjects to report feeling uncomfortably warm, to rate the air quality as worse, to report increased sleepiness and higher intensity of several acute health symptoms. Eardrum temperature, skin temperature, heart rate and body weight loss all increased significantly at this exposure, arterial oxygen...

  19. Progress in Assessing Air Pollutant Risks from In Vitro Exposures: Matching Ozone Dose and Effect in Human Air Way Cells

    Science.gov (United States)

    In vitro exposures to air pollutants could, in theory, facilitate a rapid and detailed assessment of molecular mechanisms of toxicity. However, it is difficult to ensure that the dose of a gaseous pollutant to cells in tissue culture is similar to that of the same cells during in...

  20. Impact of acute exposure to air pollution on the cardiorespiratory performance of military firemen

    Directory of Open Access Journals (Sweden)

    R.S. Oliveira

    2006-12-01

    Full Text Available The objective of the present study was to determine the impact of acute short-term exposure to air pollution on the cardiorespiratory performance of military fireman living and working in the city of Guarujá, São Paulo, Brazil. Twenty-five healthy non-smoking firemen aged 24 to 45 years had about 1 h of exposure to low and high levels of air pollution. The tests consisted of two phases: phase A, in Bertioga, a town with low levels of air pollution, and phase B, in Cubatão, a polluted town, with a 7-day interval between phases. The volunteers remained in the cities (Bertioga/Cubatão only for the time required to perform the tests. Cumulative load 10 ± 2 min-long exertion tests were performed on a treadmill, consisting of a 2-min stage at a load of 7 km/h, followed by increasing exertion of 1 km h-1 min-1 until the maximum individual limit. There were statistically significant differences (P < 0.05 in anaerobic threshold (AT between Cubatão (35.04 ± 4.91 mL kg-1 min-1 and Bertioga (36.98 ± 5.62 mL kg-1 min-1; P = 0.01, in the heart rate at AT (AT HR; Cubatão 152.08 ± 14.86 bpm, Bertioga 157.44 ± 13.64 bpm; P = 0.001, and in percent maximal oxygen consumption at AT (AT%VO2max; Cubatão 64.56 ± 6.55%, Bertioga 67.40 ± 5.35%; P = 0.03. However, there were no differences in VO2max, maximal heart rate or velocity at AT (ATvel observed in firemen between towns. The acute exposure to pollutants in Cubatão, SP, caused a significant reduction in the performance at submaximal levels of physical exertion.

  1. Effects of Acute Exposure to Moderate Altitude on Vascular Function, Metabolism and Systemic Inflammation

    Science.gov (United States)

    Stöwhas, Anne-Christin; Latshang, Tsogyal D.; Lo Cascio, Christian M.; Lautwein, Sina; Stadelmann, Katrin; Tesler, Noemi; Ayers, Lisa; Berneis, Kaspar; Gerber, Philipp A.; Huber, Reto; Achermann, Peter; Bloch, Konrad E.; Kohler, Malcolm

    2013-01-01

    Background Travel to mountain areas is popular. However, the effects of acute exposure to moderate altitude on the cardiovascular system and metabolism are largely unknown. Objectives To investigate the effects of acute exposure to moderate altitude on vascular function, metabolism and systemic inflammation. Methods In 51 healthy male subjects with a mean (SD) age of 26.9 (9.3) years, oxygen saturation, blood pressure, heart rate, arterial stiffness, lipid profiles, low density lipoprotein (LDL) particle size, insulin resistance (HOMA-index), highly-sensitive C-reactive protein and pro-inflammatory cytokines were measured at 490 m (Zurich) and during two days at 2590 m, (Davos Jakobshorn, Switzerland) in randomized order. The largest differences in outcomes between the two altitudes are reported. Results Mean (SD) oxygen saturation was significantly lower at 2590 m, 91.0 (2.0)%, compared to 490 m, 96.0 (1.0)%, p<0.001. Mean blood pressure (mean difference +4.8 mmHg, p<0.001) and heart rate (mean difference +3.3 bpm, p<0.001) were significantly higher at 2590 m, compared to 490 m, but this was not associated with increased arterial stiffness. At 2590 m, lipid profiles improved (median difference triglycerides −0.14 mmol/l, p = 0.012, HDL +0.08 mmol/l, p<0.001, total cholesterol/HDL-ratio −0.25, p = 0.001), LDL particle size increased (median difference +0.45 nm, p = 0.048) and hsCRP decreased (median difference −0.18 mg/l, p = 0.024) compared to 490 m. No significant change in pro-inflammatory cytokines or insulin resistance was observed upon ascent to 2590 m. Conclusions Short-term stay at moderate altitude is associated with increased blood pressure and heart rate likely due to augmented sympathetic activity. Exposure to moderate altitude improves the lipid profile and systemic inflammation, but seems to have no significant effect on glucose metabolism. Trial Registration ClinicalTrials.gov NCT01130948 PMID:23936377

  2. Effects of acute exposure to moderate altitude on vascular function, metabolism and systemic inflammation.

    Directory of Open Access Journals (Sweden)

    Anne-Christin Stöwhas

    Full Text Available BACKGROUND: Travel to mountain areas is popular. However, the effects of acute exposure to moderate altitude on the cardiovascular system and metabolism are largely unknown. OBJECTIVES: To investigate the effects of acute exposure to moderate altitude on vascular function, metabolism and systemic inflammation. METHODS: In 51 healthy male subjects with a mean (SD age of 26.9 (9.3 years, oxygen saturation, blood pressure, heart rate, arterial stiffness, lipid profiles, low density lipoprotein (LDL particle size, insulin resistance (HOMA-index, highly-sensitive C-reactive protein and pro-inflammatory cytokines were measured at 490 m (Zurich and during two days at 2590 m, (Davos Jakobshorn, Switzerland in randomized order. The largest differences in outcomes between the two altitudes are reported. RESULTS: Mean (SD oxygen saturation was significantly lower at 2590 m, 91.0 (2.0%, compared to 490 m, 96.0 (1.0%, p<0.001. Mean blood pressure (mean difference +4.8 mmHg, p<0.001 and heart rate (mean difference +3.3 bpm, p<0.001 were significantly higher at 2590 m, compared to 490 m, but this was not associated with increased arterial stiffness. At 2590 m, lipid profiles improved (median difference triglycerides -0.14 mmol/l, p=0.012, HDL +0.08 mmol/l, p<0.001, total cholesterol/HDL-ratio -0.25, p=0.001, LDL particle size increased (median difference +0.45 nm, p=0.048 and hsCRP decreased (median difference -0.18 mg/l, p=0.024 compared to 490 m. No significant change in pro-inflammatory cytokines or insulin resistance was observed upon ascent to 2590 m. CONCLUSIONS: Short-term stay at moderate altitude is associated with increased blood pressure and heart rate likely due to augmented sympathetic activity. Exposure to moderate altitude improves the lipid profile and systemic inflammation, but seems to have no significant effect on glucose metabolism. TRIAL REGISTRATION: ClinicalTrials.gov NCT01130948.

  3. Acute lung injury following inhalation exposure to nerve agent VX in guinea pigs.

    Science.gov (United States)

    Wright, Benjamin S; Rezk, Peter E; Graham, Jacob R; Steele, Keith E; Gordon, Richard K; Sciuto, Alfred M; Nambiar, Madhusoodana P

    2006-05-01

    A microinstillation technique of inhalation exposure was utilized to assess lung injury following chemical warfare nerve agent VX [methylphosphonothioic acid S-(2-[bis(1-methylethyl)amino]ethyl) O-ethyl ester] exposure in guinea pigs. Animals were anesthetized using Telazol-meditomidine, gently intubated, and VX was aerosolized using a microcatheter placed 2 cm above the bifurcation of the trachea. Different doses (50.4 microg/m3, 70.4 micro g/m(m3), 90.4 microg/m(m3)) of VX were administered at 40 pulses/min for 5 min. Dosing of VX was calculated by the volume of aerosol produced per 200 pulses and diluting the agent accordingly. Although the survival rate of animals exposed to different doses of VX was similar to the controls, nearly a 20% weight reduction was observed in exposed animals. After 24 h of recovery, the animals were euthanized and bronchoalveolar lavage (BAL) was performed with oxygen free saline. BAL was centrifuged and separated into BAL fluid (BALF) and BAL cells (BALC) and analyzed for indication of lung injury. The edema by dry/wet weight ratio of the accessory lobe increased 11% in VX-treated animals. BAL cell number was increased in VX-treated animals compared to controls, independent of dosage. Trypan blue viability assay indicated an increase in BAL cell death in 70.4 microg/m(m3) and 90.4 microg/m(m3) VX-exposed animals. Differential cell counting of BALC indicated a decrease in macrophage/monocytes in VX-exposed animals. The total amount of BAL protein increased gradually with the exposed dose of VX and was highest in animals exposed to 90.4 microg/m(m3), indicating that this dose of VX caused lung injury that persisted at 24 h. In addition, histopathology results also suggest that inhalation exposure to VX induces acute lung injury.

  4. Chronic and acute exposures to the world trade center disaster and lower respiratory symptoms: area residents and workers.

    Science.gov (United States)

    Maslow, Carey B; Friedman, Stephen M; Pillai, Parul S; Reibman, Joan; Berger, Kenneth I; Goldring, Roberta; Stellman, Steven D; Farfel, Mark

    2012-06-01

    We assessed associations between new-onset (post-September 11, 2001 [9/11]) lower respiratory symptoms reported on 2 surveys, administered 3 years apart, and acute and chronic 9/11-related exposures among New York City World Trade Center-area residents and workers enrolled in the World Trade Center Health Registry. World Trade Center-area residents and workers were categorized as case participants or control participants on the basis of lower respiratory symptoms reported in surveys administered 2 to 3 and 5 to 6 years after 9/11. We created composite exposure scales after principal components analyses of detailed exposure histories obtained during face-to-face interviews. We used multivariate logistic regression models to determine associations between lower respiratory symptoms and composite exposure scales. Both acute and chronic exposures to the events of 9/11 were independently associated, often in a dose-dependent manner, with lower respiratory symptoms among individuals who lived and worked in the area of the World Trade Center. Study findings argue for detailed assessments of exposure during and after events in the future from which potentially toxic materials may be released and for rapid interventions to minimize exposures and screen for potential adverse health effects.

  5. Neurobehavioral and neurophysiological effects after acute exposure to a single peak of 200 ppm toluene in healthy volunteers.

    Science.gov (United States)

    Kobald, S Oliver; Wascher, Edmund; Blaszkewicz, Meinolf; Golka, Klaus; van Thriel, Christoph

    2015-05-01

    The solvent toluene has neurotoxic properties that are especially relevant in the working environment. Short-term exposure limits (STELs) vary from 50 ppm up to 300 ppm across countries but their acute effects remain elusive in humans. Several in vitro and in vivo studies elucidated that toluene acutely acts by perturbations of different neurotransmitter systems. More specifically visual evoked potentials (VEPs) of rats are decreased after acute toluene exposure, leading to the assumption that particularly visual attention processes might be a target of toluene in humans. Therefore a visual change detection task was applied to measure both neurobehavioral and neurophysiological effects by using electroencephalography (EEG) after a single peak exposure to 200 ppm toluene. Performance and event-related components of the EEG were examined before and after exposure in a toluene-exposed and a control group. Thirty-three young healthy volunteers participated in this study. The behavioral results of the experiment indicate that toluene impairs the rate of correct responses especially in task conditions in which an irrelevant distractor is given, while the response times did not differ between both groups. The neurophysiological findings hint toward a less efficient visual processing of behaviorally relevant stimuli and an increased distractibility by irrelevant distractors. Thus the present results are a promising starting point for further research specifically targeting visual attention after toluene exposure and the reconsideration of the presently very heterogeneous STELs.

  6. Effects of acute exposure to WIFI signals (2.45GHz) on heart variability and blood pressure in Albinos rabbit.

    Science.gov (United States)

    Saili, Linda; Hanini, Amel; Smirani, Chiraz; Azzouz, Ines; Azzouz, Amina; Sakly, Mohsen; Abdelmelek, Hafedh; Bouslama, Zihad

    2015-09-01

    Electrocardiogram and arterial pressure measurements were studied under acute exposures to WIFI (2.45GHz) during one hour in adult male rabbits. Antennas of WIFI were placed at 25cm at the right side near the heart. Acute exposure of rabbits to WIFI increased heart frequency (+22%) and arterial blood pressure (+14%). Moreover, analysis of ECG revealed that WIFI induced a combined increase of PR and QT intervals. By contrast, the same exposure failed to alter maximum amplitude and P waves. After intravenously injection of dopamine (0.50ml/kg) and epinephrine (0.50ml/kg) under acute exposure to RF we found that, WIFI alter catecholamines (dopamine, epinephrine) action on heart variability and blood pressure compared to control. These results suggest for the first time, as far as we know, that exposure to WIFI affect heart rhythm, blood pressure, and catecholamines efficacy on cardiovascular system; indicating that radiofrequency can act directly and/or indirectly on cardiovascular system.

  7. Studies of adaptive response and mutation induction in MCF-10A cells following exposure to chronic or acute ionizing radiation.

    Science.gov (United States)

    Manesh, Sara Shakeri; Sangsuwan, Traimate; Wojcik, Andrzej; Haghdoost, Siamak

    2015-10-01

    A phenomenon in which exposure to a low adapting dose of radiation makes cells more resistant to the effects of a subsequent high dose exposure is termed radio-adaptive response. Adaptive response could hypothetically reduce the risk of late adverse effects of chronic or acute radiation exposures in humans. Understanding the underlying mechanisms of such responses is of relevance for radiation protection as well as for the clinical applications of radiation in medicine. However, due to the variability of responses depending on the model system and radiation condition, there is a need to further study under what conditions adaptive response can be induced. In this study, we analyzed if there is a dose rate dependence for the adapting dose, assuming that the adapting dose induces DNA response/repair pathways that are dose rate dependent. MCF-10A cells were exposed to a 50mGy adapting dose administered acutely (0.40Gy/min) or chronically (1.4mGy/h or 4.1mGy/h) and then irradiated by high acute challenging doses. The endpoints of study include clonogenic cell survival and mutation frequency at X-linked hprt locus. In another series of experiment, cells were exposed to 100mGy and 1Gy at different dose rates (acutely and chronically) and then the mutation frequencies were studied. Adaptive response was absent at the level of clonogenic survival. The mutation frequencies were significantly decreased in the cells pre-exposed to 50mGy at 1.4mGy/h followed by 1Gy acute exposure as challenging dose. Importantly, at single dose exposures (1 Gy or 100mGy), no differences at the level of mutation were found comparing different dose rates. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Effects of chronic elevated ozone exposure on gas exchange responses of adult beech trees (Fagus sylvatica) as related to the within-canopy light gradient

    Energy Technology Data Exchange (ETDEWEB)

    Kitao, Mitsutoshi [Hokkaido Research Center, Forestry and Forest Products Research Institute, Sapporo 062-8516 (Japan)], E-mail: kitao@ffpri.affrc.go.jp; Loew, Markus [Ecophysiology of Plants, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Heerdt, Christian [Bioclimatology and Air Pollution Research, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Grams, Thorsten E.E.; Haeberle, Karl-Heinz; Matyssek, Rainer [Ecophysiology of Plants, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany)

    2009-02-15

    The effects of elevated O{sub 3} on photosynthetic properties in adult beech trees (Fagus sylvatica) were investigated in relation to leaf mass per area as a measure of the gradually changing, within-canopy light availability. Leaves under elevated O{sub 3} showed decreased stomatal conductance at unchanged carboxylation capacity of Rubisco, which was consistent with enhanced {delta}{sup 13}C of leaf organic matter, regardless of the light environment during growth. In parallel, increased energy demand for O{sub 3} detoxification and repair was suggested under elevated O{sub 3} owing to enhanced dark respiration. Only in shade-grown leaves, light-limited photosynthesis was reduced under elevated O{sub 3}, this effect being accompanied by lowered F{sub v}/F{sub m}. These results suggest that chronic O{sub 3} exposure primarily caused stomatal closure to adult beech trees in the field regardless of the within-canopy light gradient. However, light limitation apparently raised the O{sub 3} sensitivity of photosynthesis and accelerated senescence in shade leaves. - Across leaf differentiation in adult beech crowns, elevated ozone acted through stomatal closure on gas exchange although enhancing photosynthetic sensitivity of shaded leaves.

  9. A case of severe neurotoxicity associated with exposure to 1-bromopropane, an alternative to ozone-depleting or global-warming solvents.

    Science.gov (United States)

    Samukawa, Makoto; Ichihara, Gaku; Oka, Nobuyuki; Kusunoki, Susumu

    2012-09-10

    Health hazard alerts to 1-bromopropane, an alternative to ozone layer-damaging organic solvents, have been issued by some countries. Herein, we report a new case of 1-bromopropane-induced neurotoxicity. A 43-year-old male industrial worker developed muscle weakness, pain, numbness, and gait disturbance. Neurological examination indicated sensory ataxic neuropathy associated with mild impairment of upper motor neurons. He had used 1-bromopropane as a cleaning agent for metal parts at his workplace without appropriate protection. The serum bromide level was elevated at the onset of clinical manifestations. Histopathologic examination of sural nerve biopsy showed axonal damage. Under the tentative diagnosis of 1-bromopropane toxicity, he was kept away from exposure to the solvent. This resulted in gradual improvement of symptoms, recovery of motor function, and resolution of sensory deficits. The diagnosis of 1-bromopropane neurotoxicity in this case was based on details of the work environment, the clinical course, and laboratory and pathologic findings. To our knowledge, this is the first report that describes nerve biopsy findings in a human case.

  10. Persistence of Breakage in Specific Chromosome Bands 6 Years after Acute Exposure to Oil

    Science.gov (United States)

    Francés, Alexandra; Hildur, Kristin; Barberà, Joan Albert; Rodríguez-Trigo, Gema; Zock, Jan-Paul; Giraldo, Jesús; Monyarch, Gemma; Rodriguez-Rodriguez, Emma; de Castro Reis, Fernanda; Souto, Ana; Gómez, Federico P.; Pozo-Rodríguez, Francisco; Templado, Cristina; Fuster, Carme

    2016-01-01

    analyses were performed in 47 exposed individuals. A total of 251 breakpoints in exposed individuals) were identified, showing a non-uniform distribution in the human ideogram. Ten chromosome bands were found to be especially prone to breakage through both statistical methods. By comparing these bands with those observed in certain exposed individuals who had already participated the previous study, it was found in both studies that four bands (2q21, 3q27, 5q31 and 17p11.2) are particularly sensitive to breakage. Additionally, the dysfunction in DNA repair mechanisms was not significantly higher in oil-exposed individuals than in non-exposed individuals. Limitations The sample size and the possibility of some kind of selection bias should be considered. Genotoxic results cannot be extrapolated to the high number of individuals who participated occasionally in clean-up tasks. Conclusion Our findings show the existence of at least four target bands (2q21, 3q27, 5q31 and 17p11.2) with a greater propensity to break over time after an acute exposure to oil. The breaks in these bands, which are commonly involved in hematological cancer, may explain the increase of cancer risk reported in chronically benzene-exposed individuals. In addition, a more efficiency of the DNA repair mechanisms has been detected six years after in fishermen who were highly exposed to the oil spill. To date, only this study, performed by our group on the previous and present genotoxic effects, has analyzed the chromosomal regions affected by breakage after an acute oil exposure. PMID:27479010

  11. 1-Bromopropane, an alternative to ozone layer depleting solvents, is dose-dependently neurotoxic to rats in long-term inhalation exposure.

    Science.gov (United States)

    Ichihara, G; Kitoh, J; Yu, X; Asaeda, N; Iwai, H; Kumazawa, T; Shibata, E; Yamada, T; Wang, H; Xie, Z; Takeuchi, Y

    2000-05-01

    1-Bromopropane has been newly introduced as an alternative to ozone layer-depleting solvents. We aimed to clarify the dose-dependent effects of 1-bromopropane on the nervous system. Forty-four Wistar male rats were randomly divided into 4 groups of 11 each. The groups were exposed to 200, 400, or 800 ppm of 1-bromopropane or only fresh air 8 h per day for 12 weeks. Grip strength of forelimbs and hind limbs, maximum motor nerve conduction velocity (MCV), and distal latency (DL) of the tail nerve were measured in 9 rats of each group every 4 weeks. The other 2 rats of each group were perfused at the end of the experiment for morphological examinations. The rats of the 800-ppm group showed poor kicking and were not able to stand still on the slope. After a 12-week exposure, forelimb grip strength decreased significantly at 800 ppm and hind limb grip strength decreased significantly at both 400 and 800 ppm or after a 12-week exposure. MCV and DL of the tail nerve deteriorated significantly at 800 ppm. Ovoid or bubble-like debris of myelin sheaths was prominent in the unraveled muscular branch of the posterior tibial nerve in the 800-ppm group. Swelling of preterminal axons in the gracile nucleus increased in a dose-dependent manner. Plasma creatine phosphokinase (CPK) decreased dose-dependently with significant changes at 400 and 800 ppm. 1-Bromopropane induced weakness in the muscle strength of rat limbs and deterioration of MCV and DL in a dose-dependent manner, with morphological changes in peripheral nerve and preterminal axon in the gracile nucleus. 1-Bromopropane may be seriously neurotoxic to humans and should thus be used carefully in the workplace.

  12. Mapping ozone risks for rice in China for years 2000 and 2020 with flux-based and exposure-based doses

    Science.gov (United States)

    Tang, Haoye; Pang, Jing; Zhang, Gongxuan; Takigawa, Masayuki; Liu, Gang; Zhu, Jianguo; Kobayashi, Kazuhiko

    2014-04-01

    We parameterized a multiplicative model of stomatal conductance (gsto) for O3 uptake by rice leaves with the field measurements in a fully open-air ozone (O3) fumigation experiment. The estimated gsto compared well with the observed one (r2 = 0.79). By using the gsto model for O3 uptake, we estimated a flux-based O3 risk (POD6, accumulated stomatal flux of O3 above a threshold of 6 nmol m-2 s-1) for rice across China in years 2000 and 2020, and compared it with the exposure-based O3 risk (AOT40, accumulated hourly O3 concentration above 40 ppb during daytime) for the same period. For the year 2000, both POD6 and AOT40 indicated the middle and lower reaches of Yangtze River and the south China being at the highest O3 risk. From the years 2000-2020, the O3 risks are projected to double (POD6) or triple (AOT40) in a majority of rice producing areas in the above two regions. Among three major rice cropping in the middle and lower reaches of Yangtze River, double-late rice is projected to have lower O3 risk than double-early rice and single rice on the either O3 risk measure in both 2000 and 2020. In south China, on the other hand, the O3 risks for double-late rice are comparable to that for early double-rice. In this study, the O3 risk was not measured as yield loss but as O3 flux and O3 exposure. The crop loss estimation would require a relationship between O3 flux and yield loss for major rice production regions across China.

  13. Acute Radiation Effects Resulting from Exposure to Solar Particle Event-Like Radiation

    Science.gov (United States)

    Kennedy, Ann; Cengel, Keith

    2012-07-01

    A major solar particle event (SPE) may place astronauts at significant risk for the acute radiation syndrome (ARS), which may be exacerbated when combined with other space flight stressors, such that the mission or crew health may be compromised. The National Space Biomedical Research Institute (NSBRI) Center of Acute Radiation Research (CARR) is focused on the assessment of risks of adverse biological effects related to the ARS in animal models exposed to space flight stressors combined with the types of radiation expected during an SPE. As part of this program, FDA-approved drugs that may prevent and/or mitigate ARS symptoms are being evaluated. The CARR studies are focused on the adverse biological effects resulting from exposure to the types of radiation, at the appropriate energies, doses and dose-rates, present during an SPE (and standard reference radiations, gamma rays or electrons). The ARS is a phased syndrome which often includes vomiting and fatigue. Other acute adverse biologic effects of concern are the loss of hematopoietic cells, which can result in compromised bone marrow and immune cell functions. There is also concern for skin damage from high SPE radiation doses, including burns, and resulting immune system dysfunction. Using 3 separate animal model systems (ferrets, mice and pigs), the major ARS biologic endpoints being evaluated are: 1) vomiting/retching and fatigue, 2) hematologic changes (with focus on white blood cells) and immune system changes resulting from exposure to SPE radiation with and without reduced weightbearing conditions, and 3) skin injury and related immune system functions. In all of these areas of research, statistically significant adverse health effects have been observed in animals exposed to SPE-like radiation. Countermeasures for the management of ARS symptoms are being evaluated. New research findings from the past grant year will be discussed. Acknowledgements: This research is supported by the NSBRI Center of Acute

  14. Activity of ozonated water and ozone against Staphylococcus aureus and Pseudomonas aeruginosa biofilms

    Science.gov (United States)

    Bialoszewski, Dariusz; Pietruczuk-Padzik, Anna; Kalicinska, Agnieszka; Bocian, Ewa; Czajkowska, Magdalena; Bukowska, Bozena; Tyski, Stefan

    2011-01-01

    Summary Background The known bactericidal properties of ozone have not been checked in relation to its action on bacterial biofilms. This is especially true of ozonated fluids. The aim of this study was to investigate the bactericidal activity of ozonated water and that of a mixture of ozone and oxygen against biofilms. Material/Methods Eighteen clinical strains of Staphylococcus aureus and Pseudomonas aeruginosa exhibiting various levels of antibiotic sensitivity were investigated. Bacteria were cultured in biofilm form on polystyrene titration plates for periods of 2 to 72 hours. The biofilms formed in this way were exposed to in statu nascendi ozonated water produced in a prototype device that had been tested in clinical conditions, or to a mixture of oxygen and ozone generated in the same device. Live cells in the biofilm were stained with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) bromide solution. The degree of reduction of viable bacteria following ozone exposure was determined. Results Ozonated water was found to be an effective bactericidal agent against biofilms after as little as 30 seconds of exposure, while the bactericidal activity of the ozone-oxygen solution was much lower. Prolongation of the duration of biofilm exposure to the gaseous disinfectant to 40 minutes led to a reduction in the viable cell count, which nevertheless remained high. Conclusions Unlike the ozone-oxygen mixture, ozonated water effectively destroys bacterial biofilms in vitro. PMID:22037737

  15. Simulating the impacts of chronic ozone exposure on plant conductance and photosynthesis, and on the regional hydroclimate using WRF/Chem

    Science.gov (United States)

    Li, Jialun; Mahalov, Alex; Hyde, Peter

    2016-11-01

    The Noah-Multiparameterization land surface model in the Weather Research and Forecasting (WRF) with Chemistry (WRF/Chem) is modified to include the effects of chronic ozone exposure (COE) on plant conductance and photosynthesis (PCP) found from field experiments. Based on the modified WRF/Chem, the effects of COE on regional hydroclimate have been investigated over the continental United States. Our results indicate that the model with/without modification in its current configuration can reproduce the rainfall and temperature patterns of the observations and reanalysis data, although it underestimates rainfall in the central Great Plains and overestimates it in the eastern coast states. The experimental tests on the effects of COE include setting different thresholds of ambient ozone concentrations ([O3]) and using different linear regressions to quantify PCP against the COE. Compared with the WRF/Chem control run (i.e., without considering the effects of COE), the modified model at different experiment setups improves the simulated estimates of rainfall and temperatures in Texas and regions to the immediate north. The simulations in June, July and August of 2007-2012 show that surface [O3] decrease latent heat fluxes (LH) by 10-27 W m-2, increase surface air temperatures (T 2) by 0.6 °C-2.0 °C, decrease rainfall by 0.9-1.4 mm d-1, and decrease runoff by 0.1-0.17 mm d-1 in Texas and surrounding areas, all of which highly depends on the precise experiment setup, especially the [O3] threshold. The mechanism producing these results is that COE decreases the LH and increases sensible heat fluxes, which in turn increases the Bowen ratios and air temperatures. This lowering of the LH also results in the decrease of convective potential and finally decreases convective rainfall. Employing this modified WRF/Chem model in any high [O3] region can improve the understanding of the interactions of vegetation, meteorology, chemistry/emissions, and crop productivity.

  16. Influence of acute exposure to high altitude on basal and postprandial plasma levels of gastroenteropancreatic peptides.

    Directory of Open Access Journals (Sweden)

    Rudolf L Riepl

    Full Text Available Acute mountain sickness (AMS is characterized by headache often accompanied by gastrointestinal complaints that vary from anorexia through nausea to vomiting. The aim of this study was to investigate the influence of high altitude on plasma levels of gastroenteropancreatic (GEP peptides and their association to AMS symptoms. Plasma levels of 6 GEP peptides were measured by radioimmunoassay in 11 subjects at 490 m (Munich, Germany and, after rapid passive ascent to 3454 m (Jungfraujoch, Switzerland, over the course of three days. In a second study (n = 5, the same peptides and ghrelin were measured in subjects who consumed standardized liquid meals at these two elevations. AMS symptoms and oxygen saturation were monitored. In the first study, both fasting (morning 8 a.m. and stimulated (evening 8 p.m. plasma levels of pancreatic polypeptide (PP and cholecystokinin (CCK were significantly lower at high altitude as compared to baseline, whereas gastrin and motilin concentrations were significantly increased. Fasting plasma neurotensin was significantly enhanced whereas stimulated levels were reduced. Both fasting and stimulated plasma motilin levels correlated with gastrointestinal symptom severity (r = 0.294, p = 0.05, and r = 0.41, p = 0.006, respectively. Mean O(2-saturation dropped from 96% to 88% at high altitude. In the second study, meal-stimulated integrated (= area under curve plasma CCK, PP, and neurotensin values were significantly suppressed at high altitude, whereas integrated levels of gastrin were increased and integrated VIP and ghrelin levels were unchanged. In summary, our data show that acute exposure to a hypobaric hypoxic environment causes significant changes in fasting and stimulated plasma levels of GEP peptides over consecutive days and after a standardized meal. The changes of peptide levels were not uniform. Based on the inhibition of PP and neurotensin release a reduction of the cholinergic tone can be postulated.

  17. Genotoxic Evaluation of Mikania laevigata Extract on DNA Damage Caused by Acute Coal Dust Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, T.P.; Heuser, V.D.; Tavares, P.; Leffa, D.D.; da Silva, G.A.; Citadini-Zanette, V.; Romao, P.R.T.; Pinho, R.A.; Streck, E.L.; Andrade,V.M. [University of Extremo Catarinense, Criciuma, SC (Brazil)

    2009-06-15

    We report data on the possible antigenotoxic activity of Mikania laevigata extract (MLE) after acute intratracheal instillation of coal dust using the comet assay in peripheral blood, bone marrow, and liver cells and the micronucleus test in peripheral blood of Wistar rats. The animals were pretreated for 2 weeks with saline solution (groups 1 and 2) or MLE (100 mg/kg) (groups 3 and 4). On day 15, the animals were anesthetized with ketamine (80 mg/kg) and xylazine (20 mg/kg), and gross mineral coal dust (3 mg/0.3 mL saline) (groups 2 and 4) or saline solution (0.3 mL) (groups 1 and 3) was administered directly in the lung by intratracheal administration. Fifteen days after coal dust or saline instillation, the animals were sacrificed, and the femur, liver, and peripheral blood were removed. The results showed a general increase in the DNA damage values at 8 hours for all treatment groups, probably related to surgical procedures that had stressed the animals. Also, liver cells from rats treated with coal dust, pretreated or not with MLE, showed statistically higher comet assay values compared to the control group at 14 days after exposure. These results could be expected because the liver metabolizes a variety of organic compounds to more polar by-products. On the other hand, the micronucleus assay results did not show significant differences among groups. Therefore, our data do not support the antimutagenic activity of M. laevigata as a modulator of DNA damage after acute coal dust instillation.

  18. Exploring the molecular mechanism of acute heat stress exposure in broiler chickens using gene expression profiling.

    Science.gov (United States)

    Luo, Q B; Song, X Y; Ji, C L; Zhang, X Q; Zhang, D X

    2014-08-10

    The process of heat regulation is complex and its exact molecular mechanism is not fully understood. In this study, to investigate the global gene regulation response to acute heat exposure, gene microarrays were exploited to analyze the effects of heat stress on three tissues (brain, liver, leg muscle) of the yellow broiler chicken (Gallus gallus). We detected 166 differentially expressed genes (DEGs) in the brain, 219 in the leg muscle and 317 in the liver. Six of these genes were differentially expressed in all three tissues and were validated by qRT-PCR, and included heat shock protein genes (HSPH1, HSP25), apoptosis-related genes (RB1CC1, BAG3), a cell proliferation and differentiation-related gene (ID1) and the hunger and energy metabolism related gene (PDK). All these genes might be important factors in chickens suffering from heat stress. We constructed gene co-expression networks using the DEGs of the brain, leg muscle and liver and two, four and two gene co-expression modules were identified in these tissues, respectively. Functional enrichment of these gene modules revealed that various functional clusters were related to the effects of heat stress, including those for cytoskeleton, extracellular space, ion binding and energy metabolism. We concluded that these genes and functional clusters might be important factors in chickens under acute heat stress. Further in-depth research on the newly discovered heat-related genes and functional clusters is required to fully understand their molecular functions in thermoregulation. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. A comprehensive analysis of oxidative stress in the ozone-induced lung inflammation mouse model.

    Science.gov (United States)

    Wiegman, Coen H; Li, Feng; Clarke, Colin J; Jazrawi, Elen; Kirkham, Paul; Barnes, Peter J; Adcock, Ian M; Chung, Kian F

    2014-03-01

    Ozone is an oxidizing environmental pollutant that contributes significantly to respiratory health. Exposure to increased levels of ozone has been associated with worsening of symptoms of patients with asthma and COPD (chronic obstructive pulmonary disease). In the present study, we investigated the acute and chronic effects of ozone exposure-induced oxidative stress-related inflammation mechanics in mouse lung. In particular, we investigated the oxidative stress-induced effects on HDAC2 (histone deacetylase 2) modification and activation of the Nrf2 (nuclear factor erythroid-related factor 2) and HIF-1α (hypoxia-inducible factor-1α) signalling pathways. Male C57BL/6 mice were exposed to ozone (3 p.p.m.) for 3 h a day, twice a week for a period of 1, 3 or 6 weeks. Control mice were exposed to normal air. After the last exposure, mice were killed for BAL (bronchoalveolar lavage) fluid and lung tissue collection. BAL total cell counts were elevated at all of the time points studied. This was associated with increased levels of chemokines and cytokines in all ozone-exposed groups, indicating the presence of a persistent inflammatory environment in the lung. Increased inflammation and Lm (mean linear intercept) scores were observed in chronic exposed mice, indicating emphysematous changes were present in lungs of chronic exposed mice. The antioxidative stress response was active (indicated by increased Nrf2 activity and protein) after 1 week of ozone exposure, but this ability was lost after 3 and 6 weeks of ozone exposure. The transcription factor HIF-1α was elevated in 3- and 6-week ozone-exposed mice and this was associated with increased gene expression levels of several HIF-1α target genes including Hdac2 (histone deacetylase 2), Vegf (vascular endothelial growth factor), Keap1 (kelch-like ECH-associated protein 1) and Mif (macrophage migration inhibitory factor). HDAC2 protein was found to be phosphorylated and carbonylated in nuclear and cytoplasm fractions

  20. 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

  1. Acute exposure to 17α-ethinylestradiol disrupts audience effect on male-female interactions in Betta splendens.

    Science.gov (United States)

    Forette, Lindsay M; Mannion, Krystal L; Dzieweczynski, Teresa L

    2015-04-01

    Endocrine disrupting chemicals can negatively impact the morphology and behavior of organisms inhabiting polluted waters. Male-typical behaviors are often reduced after exposure, suggesting that exposure may have population-level effects. One way in which exposure may exert population-level effects is by interfering with communication within a network of individuals. Acute exposure to the estrogen mimic 17α-ethinylestradiol (EE2) disrupts the ability of male Siamese fighting fish, Betta splendens, to modify their behavior during male-male interactions when an audience is present. However, it is unknown whether audience effects during male-female interactions may be similarly altered. To examine this, male-female pairs that were given an acute exposure to EE2 or remained unexposed interacted in the presence of a female, male, or no audience. Sex differences were found between unexposed males and females. More interactant-directed gill flaring was displayed by control males when a male audience was present while control females performed this behavior more in the presence of an audience, regardless of sex. Both males and females in the control group performed more interactant-directed tail beats in the presence of a female audience. EE2 exposure made all audience effects disappear as treated males and females did not differ in their responses between audience types. These results demonstrate that acute exposure to EE2 may disrupt behavioral adjustments to audience type within a social network. This disruption may, in turn, influence population dynamics in this species as both males and females use information obtained from observing interactions in later encounters with the observed individuals.

  2. Foliar injury response of petunia and kidney bean to simultaneous and alternate exposures to ozone and pan

    Science.gov (United States)

    Nouchi, Isamu; Mayumi, Hirokazu; Yamazoe, Fumio

    Petunia at about 6 weeks old and kidney bean at two growing stages (6-7 days old and 16-18 days old) were exposed separately to O 3, (0-0.40 ppm) and PAN (0-0.25 ppm) for 4 h and to the mixture for the same time. In addition, petunia was exposed to O, (0.10-0.40 ppm) and then PAN (0.010-0.040 ppm) for 4 h, respectively. Foliar injury of petunia and kidney bean in exposures to the mixtures of O 3 and PAN was significantly smaller than that induced by each oxidant, with the exception of PAN injury on young leaves of 16-18 day-old kidney bean. The percentage of foliar injury caused by either of the mixed pollutants decreased with an increase of the concentration of the other oxidant, and was found to approximate a logarithmic function of the combined pollutant concentrations expressed as O 3, minum PAN or vice versa. Alternate exposures caused no additive or synergistic injuries.

  3. Oral exposure to Phytomonas serpens attenuates thrombocytopenia and leukopenia during acute infection with Trypanosoma cruzi.

    Directory of Open Access Journals (Sweden)

    Rosiane V da Silva

    Full Text Available Mice infected with Trypanosoma cruzi, the agent of Chagas disease, rapidly develop anemia and thrombocytopenia. These effects are partially promoted by the parasite trans-sialidase (TS, which is shed in the blood and depletes sialic acid from the platelets, inducing accelerated platelet clearance and causing thrombocytopenia during the acute phase of disease. Here, we demonstrate that oral immunization of C57BL/6 mice with Phytomonas serpens, a phytoflagellate parasite that shares common antigens with T. cruzi but has no TS activity, reduces parasite burden and prevents thrombocytopenia and leukopenia. Immunization also reduces platelet loss after intraperitoneal injection of TS. In addition, passive transfer of immune sera raised in mice against P. serpens prevented platelet clearance. Thus, oral exposure to P. serpens attenuates the progression of thrombocytopenia induced by TS from T. cruzi. These findings are not only important for the understanding of the pathogenesis of T. cruzi infection but also for developing novel approaches of intervention in Chagas disease.

  4. Effect of acute exposure to moderate altitude on muscle power: hypobaric hypoxia vs. normobaric hypoxia.

    Science.gov (United States)

    Feriche, Belén; García-Ramos, Amador; Calderón-Soto, Carmen; Drobnic, Franchek; Bonitch-Góngora, Juan G; Galilea, Pedro A; Riera, Joan; Padial, Paulino

    2014-01-01

    When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest P(mean) obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to P(max) (∼ 3%) and maximal strength (1 RM) (∼ 6%) in G1 attributable to the climb to altitude (Ppress.

  5. 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

  6. 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.

  7. Effects of an acute and a sub-chronic 900 MHz GSM exposure on brain activity and behaviors of rats

    Energy Technology Data Exchange (ETDEWEB)

    Elsa Brillaud; Aleksandra Piotrowski; Anthony Lecomte; Franck Robidel; Rene de Seze [Toxicology Unit, INERIS, Verneuil en Halatte (France)

    2006-07-01

    Radio frequencies are suspected to produce health effects. Concerning the mobile phone technology, according to position during use (close to the head), possible effects of radio frequencies on the central nervous system have to be evaluated. Previous works showed contradictory results, possibly due to experimental design diversity. In the framework of R.A.M.P. 2001 project, we evaluated possible effect of a 900 MHz GSM exposure on the central nervous system of rat at a structural, a functional and a behavioral level after acute or sub-chronic exposures. Rats were exposed using a loop antenna system to different S.A.R. levels and durations, according to results of the French C.O.M.O.B.I.O. 2001 project. A functional effect was found (modification of the cerebral activity and increase of the glia surface) after an acute exposure, even at a low level of brain averaged S.A.R. (1.5 W/kg). No cumulative effect was observed after a sub-chronic exposure (same amplitude of the effect). No structural or behavioral consequence was noted. We do not conclude on the neurotoxicity of the 900 MHz GSM exposure on the rat brain. Our results do not indicate any health risk. (authors)

  8. Assessment of locomotion behavioral defects induced by acute toxicity from heavy metal exposure in nematode Caenorhabditis elegans

    Institute of Scientific and Technical Information of China (English)

    WANG Dayong; XING Xiaojuan

    2008-01-01

    Locomotion behaviors are susceptible to disruption by a broad spectrum of chemicals and environmental stresses. However, no systematic testing of locomotion behavior defects induced by metal exposure has been conducted in the model organism of nematode Caenorhabditis elegans. In this study, the acute toxicity from heavy metal exposure on the locomotion behaviors was analyzed in nematodes. Endpoints of head thrash, body bend, forward turn, backward turn, and Omega/U turn were chosen to evaluate the locomotion behavioral defects. Our data suggest that the endpoints of head thrash, body bend, and forward turn will be useful for the evaluation of heavy metal toxicity in nematodes. The endpoint of head thrash could detect the toxicity from Cd, Co, Cr, Cu, Hg, and Pb exposures at a low concentration (2.5 μmol/L). The endpoint of body bend could be explored to evaluate the toxicity from all assayed heavy metal exposures at different concentrations, whereas the endpoint of forward turn will be more useful for the evaluation of heavy metal toxicity at high concentrations. Thus, endpoints of these locomotion behaviors establish a fast and economic way to assess the presence of acute toxicity from heavy metal exposure in nematode C. elegans.

  9. Exposure to elevated ozone levels differentially affects the antioxidant capacity and the redox homeostasis of two subtropical Phaseolus vulgaris L. varieties.

    Science.gov (United States)

    Caregnato, Fernanda Freitas; Bortolin, Rafael Calixto; Divan Junior, Armando Molina; Moreira, José Cláudio Fonseca

    2013-09-01

    Ozone (O3) has become one of the most toxic air pollutants to plants worldwide. However, investigations on O3 impacts on crops health and productivity in South America countries are still scarce. The present study analyzed the differences on the enzymatic and non-enzymatic antioxidant system in foliar tissue of two subtropical Phaseolus vulgaris varieties exposed to high O3 concentration. Both varieties were negatively impacted by the pollutant, but the responses between each variety were quite distinct. Results revealed that Irai has higher constitutive levels of reactive oxygen species (ROS) and ascorbate (AsA) concentration, but lower total thiol levels and catalase immunocontent. In this variety catalase protein concentration was increased after O3 exposure, indicating a better cellular capacity to reduce hydrogen peroxide. On the opposite, Fepagro 26-exposed plants increased ROS generation and AsA concentration, but had the levels of total thiol content and catalase protein unchanged. Furthermore, O3 treatment reduced the levels of chlorophylls a and b, and the relationship analysis between the chlorophyll ratio (a/b) and protein concentration were positively correlated indicating that photosynthetic apparatus is compromised, and thus probably is the biomass acquisition on Fepagro 26. Differently, O3 treatment of Irai did not affect chlorophylls a and b content, and loss on the protein content was lower. Altogether, these data suggest that early accumulation of ROS on Fepagro 26 are associated with an insufficient leaf antioxidant capacity, which leads to cell structure disruption and impairs the photosynthesis. Irai seems to be more tolerant to O3 toxic effects than Fepagro 26, and the observed differences on O3 sensitivity between the two varieties are apparently based on constitutive differences involved in the maintenance of intracellular redox homeostasis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Acute but not chronic ethanol exposure impairs retinol oxidation in the small and large intestine of the rat

    DEFF Research Database (Denmark)

    Parlesak, Alexandr; Ellendt, K.; Lindros, K.

    2005-01-01

    BACKGROUND AND AIM: Ethanol has been shown to inhibit retinol oxidation at the level of alcohol dehydrogenase in liver and colon but not previously in the small intestine. In the present study we investigated how chronic alcohol feeding and acute ethanol exposure affects retinol dehydrogenase...... activity in the colon and small intestine of the rat. METHODS: Rats were fed ethanol in a liquid diet for six weeks. Control rats received a similar diet but with ethanol isocalorically replaced by carbohydrates. Retinol dehydrogenase was analyzed from cell cytosol samples from the small and the large...... higher, respectively). While chronic alcohol feeding did not affect these parameters, acute ethanol exposure reduced V(max) and V(max)/K(m) dose-dependently (p

  11. Effects of ozone chemistry and outside air supply on passenger self-evalua-tion of symptoms during 4-hour exposures in a simulated aircraft cabin

    DEFF Research Database (Denmark)

    Strøm-Tejsen, Peter; Tamás, Gyöngyi; Myśków, Danuta;

    2006-01-01

    flow with and without ozone. The subjects completed questionnaires to provide subjective assessments of air quality, cabin environment, intensity of symptoms commonly experienced during flight, and thermal comfort. Physiological tests, specifically Visual Acuity, Nasal Peak Flow and Skin Dryness, were...

  12. Effects of ozone exposure on `Golden' papaya fruit by photoacoustic phase-resolved method: Physiological changes associated with carbon dioxide and ethylene emission rates during ripening

    Science.gov (United States)

    Corrêa, Savio Figueira; Mota, Leonardo; Paiva, Luisa Brito; Couto, Flávio Mota do; Silva, Marcelo Gomes da; Oliveira, Jurandi Gonçalves de; Sthel, Marcelo Silva; Vargas, Helion; Miklós, András

    2011-06-01

    This work addresses the effects of ozone activity on the physiology of `Golden' papaya fruit. Depth profile analysis of double-layer biological samples was accomplished using the phase-resolved photoacoustic spectroscopy. The feasibility of the method was demonstrated by singling out the spectra of the cuticle and the pigment layers of papaya fruit. The same approach was used to monitor changes occurring on the fruit during ripening when exposed to ozone. In addition, one has performed real time studies of fluorescence parameters and the emission rates of carbon dioxide and ethylene. Finally, the amount of pigments and the changes in waxy cuticle have been monitored. Results indicate that a fruit deliberately subjected to ozone at a level of 6 ppmv underwent ripening sooner (at least 24-48 h) than a fruit stored at ambient conditions. Moreover, ozone caused a reduction in the maximum quantum yield of photosynthetic apparatus located within the skin of papaya fruit.

  13. Effects of acute and chronic waterborne lead exposure on the swimming performance and aerobic scope of fathead minnows (Pimephales promelas).

    Science.gov (United States)

    Mager, Edward M; Grosell, Martin

    2011-06-01

    Fathead minnows were subjected to an incremental velocity test using swim tunnel respirometry for the analysis of aerobic scope and swimming performance, as critical aerobic swim speed (U(crit)), following chronic exposures (33-57 ) to 0.9±0.4, 157±18 or 689±66 nmol L⁻¹ Pb and an acute exposure (24 h) to 672±35 nmol L⁻¹ Pb (mean±SEM). Assessment of Pb-induced anemia and neurological impairment were evaluated by blood hemoglobin (Hb) concentrations and a cost of transport (COT) analysis, respectively. Fish from the acute 672±35 nmol L⁻¹ Pb (24.4±1.2 BL s⁻¹) and chronic 689±66 nmol L⁻¹ Pb (24.6±0.9 BL s⁻¹) treatments exhibited reduced U(crits) compared to control fish (27.6±0.8 BL s⁻¹). Aerobic scope was reduced by acute Pb exposure (8.6±2.6 μmol O₂ g⁻¹ h⁻¹ vs. 22.6±3.8 μmol O₂ g⁻¹ h⁻¹ from controls) owing to a decrease in maximum oxygen consumption rate (38.8±0.8 μmol O₂ g⁻¹ h⁻¹ vs. 54.0±4.2 μmol O₂ g⁻¹ h⁻¹ from controls). However, no effect on aerobic scope was observed with fish chronically exposed to Pb. Significant differences were not observed for Hb concentrations or COT. These findings suggest that the impaired swimming performances arising from acute and chronic Pb exposures reflect different mechanisms of toxicity.

  14. Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum

    OpenAIRE

    Ana ePalomino; Francisco Javier ePavon; Eduardo eBlanco Calvo; Antonia eSerrano; Sergio eArrabal; Patricia eRivera; Antonio eVargas; Ainhoa eBilbao; Leticia eRubio; Fernando eRodriguez de Fonseca; Juan eSuarez

    2014-01-01

    Growing awareness of cerebellar involvement in addiction is based on the cerebellum’s intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB) and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression {cannabinoid recept...

  15. Father's occupational exposure to carcinogenic agents and childhood acute leukemia: a new method to assess exposure (a case-control study

    Directory of Open Access Journals (Sweden)

    Rodriguez-Rivera Maria

    2008-01-01

    Full Text Available Abstract Background Medical research has not been able to establish whether a father's occupational exposures are associated with the development of acute leukemia (AL in their offspring. The studies conducted have weaknesses that have generated a misclassification of such exposure. Occupations and exposures to substances associated with childhood cancer are not very frequently encountered in the general population; thus, the reported risks are both inconsistent and inaccurate. In this study, to assess exposure we used a new method, an exposure index, which took into consideration the industrial branch, specific position, use of protective equipment, substances at work, degree of contact with such substances, and time of exposure. This index allowed us to obtain a grade, which permitted the identification of individuals according to their level of exposure to known or potentially carcinogenic agents that are not necessarily specifically identified as risk factors for leukemia. The aim of this study was to determine the association between a father's occupational exposure to carcinogenic agents and the presence of AL in their offspring. Methods From 1999 to 2000, a case-control study was performed with 193 children who reside in Mexico City and had been diagnosed with AL. The initial sample-size calculation was 150 children per group, assessed with an expected odds ratio (OR of three and a minimum exposure frequency of 15.8%. These children were matched by age, sex, and institution with 193 pediatric surgical patients at secondary-care hospitals. A questionnaire was used to determine each child's background and the characteristics of the father's occupation(s. In order to determine the level of exposure to carcinogenic agents, a previously validated exposure index (occupational exposure index, OEI was used. The consistency and validity of the index were assessed by a questionnaire comparison, the sensory recognition of the work area, and an

  16. Association between exposure to environmental tobacco smoke and biomarkers of oxidative stress among patients hospitalised with acute myocardial infarction.

    Directory of Open Access Journals (Sweden)

    Ian L Megson

    Full Text Available OBJECTIVE: To determine whether exposure to environmental tobacco smoke was associated with oxidative stress among patients hospitalised for acute myocardial infarction. DESIGN: An existing cohort study of 1,261 patients hospitalised for acute myocardial infarction. SETTING: Nine acute hospitals in Scotland. PARTICIPANTS: Sixty never smokers who had been exposed to environmental tobacco smoke (admission serum cotinine ≥3.0 ng/mL were compared with 60 never smokers who had not (admission serum cotinine ≤0.1 ng/mL. INTERVENTION: None. MAIN OUTCOME MEASURES: Three biomarkers of oxidative stress (protein carbonyl, malondialdehyde (MDA and oxidised low-density lipoprotein (ox-LDL were measured on admission blood samples and adjusted for potential confounders. RESULTS: After adjusting for baseline differences in age, sex and socioeconomic status, exposure to environmental tobacco smoke was associated with serum concentrations of both protein carbonyl (beta coefficient 7.96, 95% CI 0.76, 15.17, p = 0.031 and MDA (beta coefficient 10.57, 95% CI 4.32, 16.81, p = 0.001 but not ox-LDL (beta coefficient 2.14, 95% CI -8.94, 13.21, p = 0.703. CONCLUSIONS: Exposure to environmental tobacco smoke was associated with increased oxidative stress. Further studies are requires to explore the role of oxidative stress in the association between environmental tobacco smoke and myocardial infarction.

  17. Exposure medium: key in identifying free Ag+ as the exclusive species of silver nanoparticles with acute toxicity to Daphnia magna.

    Science.gov (United States)

    Shen, Mo-Hai; Zhou, Xiao-Xia; Yang, Xiao-Ya; Chao, Jing-Bo; Liu, Rui; Liu, Jing-Fu

    2015-04-10

    It is still not very clear what roles the various Ag species play in the toxicity of silver nanoparticles (AgNPs). In this study, we found that traditional exposure media result in uncontrollable but consistent physicochemical transformation of AgNPs, causing artifacts in determination of median lethal concentration (LC50) and hindering the identification of Ag species responsible for the acute toxicity of AgNPs to Daphnia magna. This obstacle was overcome by using 8 h exposure in 0.1 mmol L(-1) NaNO3 medium, in which we measured the 8-h LC50 of seven AgNPs with different sizes and coatings, and determined the concentrations of various Ag species. The LC50 as free Ag(+) of the seven AgNPs (0.37-0.44 μg L(-1)) agreed very well with that of AgNO3 (0.40 μg L(-1)), and showed the lowest value compared to that as total Ag, total Ag(+), and dissolved Ag, demonstrating free Ag(+) is exclusively responsible for the acute toxicity of AgNPs to D. magna, while other Ag species in AgNPs have no contribution to the acute toxicity. Our results demonstrated the great importance of developing appropriate exposure media for evaluating risk of nanomaterials.

  18. Exposure Medium: Key in Identifying Free Ag+ as the Exclusive Species of Silver Nanoparticles with Acute Toxicity to Daphnia magna

    Science.gov (United States)

    Shen, Mo-Hai; Zhou, Xiao-Xia; Yang, Xiao-Ya; Chao, Jing-Bo; Liu, Rui; Liu, Jing-Fu

    2015-04-01

    It is still not very clear what roles the various Ag species play in the toxicity of silver nanoparticles (AgNPs). In this study, we found that traditional exposure media result in uncontrollable but consistent physicochemical transformation of AgNPs, causing artifacts in determination of median lethal concentration (LC50) and hindering the identification of Ag species responsible for the acute toxicity of AgNPs to Daphnia magna. This obstacle was overcome by using 8 h exposure in 0.1 mmol L-1 NaNO3 medium, in which we measured the 8-h LC50 of seven AgNPs with different sizes and coatings, and determined the concentrations of various Ag species. The LC50 as free Ag+ of the seven AgNPs (0.37-0.44 μg L-1) agreed very well with that of AgNO3 (0.40 μg L-1), and showed the lowest value compared to that as total Ag, total Ag+, and dissolved Ag, demonstrating free Ag+ is exclusively responsible for the acute toxicity of AgNPs to D. magna, while other Ag species in AgNPs have no contribution to the acute toxicity. Our results demonstrated the great importance of developing appropriate exposure media for evaluating risk of nanomaterials.

  19. Time course of systemic oxidative stress and inflammatory response induced by an acute exposure to Residual Oil Fly Ash

    Energy Technology Data Exchange (ETDEWEB)

    Marchini, T.; Magnani, N.D. [Cátedra de Química General e Inorgánica, Instituto de Bioquímica y Medicina Molecular (IBIMOL UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); Paz, M.L. [Cátedra de Inmunología, Instituto de Estudios de la Inmunidad Humoral (IDEHU UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); Vanasco, V. [Cátedra de Química General e Inorgánica, Instituto de Bioquímica y Medicina Molecular (IBIMOL UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); Tasat, D. [CESyMA, Facultad de Ciencia Tecnología, Universidad Nacional de General San Martín, Martín de Irigoyen 3100, 1650 San Martín, Buenos Aires (Argentina); González Maglio, D.H. [Cátedra de Inmunología, Instituto de Estudios de la Inmunidad Humoral (IDEHU UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, C1113AAB Buenos Aires (Argentina); and others

    2014-01-15

    It is suggested that systemic oxidative stress and inflammation play a central role in the onset and progression of cardiovascular diseases associated with the exposure to particulate matter (PM). The aim of this work was to evaluate the time changes of systemic markers of oxidative stress and inflammation, after an acute exposure to Residual Oil Fly Ash (ROFA). Female Swiss mice were intranasally instilled with a ROFA suspension (1.0 mg/kg body weight) or saline solution, and plasma levels of oxidative damage markers [thiobarbituric acid reactive substances (TBARSs) and protein carbonyls], antioxidant status [reduced (GSH) and oxidized (GSSG) glutathione, ascorbic acid levels, and superoxide dismutase (SOD) activity], cytokines levels, and intravascular leukocyte activation were evaluated after 1, 3 or 5 h of exposure. Oxidative damage to lipids and decreased GSH/GSSG ratio were observed in ROFA-exposed mice as early as 1 h. Afterwards, increased protein oxidation, decreased ascorbic acid content and SOD activity were found in this group at 3 h. The onset of an adaptive response was observed at 5 h after the ROFA exposure, as indicated by decreased TBARS plasma content and increased SOD activity. The observed increase in oxidative damage to plasma macromolecules, together with systemic antioxidants depletion, may be a consequence of a systemic inflammatory response triggered by the ROFA exposure, since increased TNF-α and IL-6 plasma levels and polymorphonuclear leukocytes activation was found at every evaluated time point. These findings contribute to the understanding of the increase in cardiovascular morbidity and mortality, in association with environmental PM inhalation. - Highlights: • An acute exposure to ROFA triggers the occurrence of systemic oxidative stress. • Changes in plasmatic oxidative stress markers appear as early as 1 h after exposure. • ROFA induces proinflammatory cytokines release and intravascular leukocyte activation. • PMN

  20. High Resolution ECG for Evaluation of QT Interval Variability during Exposure to Acute Hypoxia

    Science.gov (United States)

    Zupet, P.; Finderle, Z.; Schlegel, Todd T.; Starc, V.

    2010-01-01

    Ventricular repolarization instability as quantified by the index of QT interval variability (QTVI) is one of the best predictors for risk of malignant ventricular arrhythmias and sudden cardiac death. Because it is difficult to appropriately monitor early signs of organ dysfunction at high altitude, we investigated whether high resolution advanced ECG (HR-ECG) analysis might be helpful as a non-invasive and easy-to-use tool for evaluating the risk of cardiac arrhythmias during exposure to acute hypoxia. 19 non-acclimatized healthy trained alpinists (age 37, 8 plus or minus 4,7 years) participated in the study. Five-minute high-resolution 12-lead electrocardiograms (ECGs) were recorded (Cardiosoft) in each subject at rest in the supine position breathing room air and then after breathing 12.5% oxygen for 30 min. For beat-to-beat RR and QT variability, the program of Starc was utilized to derive standard time domain measures such as root mean square of the successive interval difference (rMSSD) of RRV and QTV, the corrected QT interval (QTc) and the QTVI in lead II. Changes were evaluated with paired-samples t-test with p-values less than 0.05 considered statistically significant. As expected, the RR interval and its variability both decreased with increasing altitude, with p = 0.000 and p = 0.005, respectively. Significant increases were found in both the rMSSDQT and the QTVI in lead II, with p = 0.002 and p = 0.003, respectively. There was no change in QTc interval length (p = non significant). QT variability parameters may be useful for evaluating changes in ventricular repolarization caused by hypoxia. These changes might be driven by increases in sympathetic nervous system activity at ventricular level.

  1. Changes in Glutamate/NMDA Receptor Subunit 1 Expression in Rat Brain after Acute and Subacute Exposure to Methamphetamine

    Directory of Open Access Journals (Sweden)

    Walailuk Kerdsan

    2009-01-01

    Full Text Available Methamphetamine (METH is a psychostimulant drug of abuse that produces long-term behavioral changes including behavioral sensitization, tolerance, and dependence. METH has been reported to induce neurotoxic effects in several areas of the brain via the dopaminergic system. Changes of dopamine function can induce malfunction of the glutamatergic system. Therefore, the aim of the present study was to examine the effects of METH administration on the expression of glutamate N-methyl-D-aspartate receptor subunit 1 (NMDAR1 in frontal cortex, striatum, and hippocampal formation after acute and subacute exposure to METH by western blotting. Male Sprague-Dawley rats were injected intraperitoneally with a single dose of 8 mg/kg METH, 4 mg/kg/day METH for 14 days and saline in acute, subacute, and control groups, respectively. A significant increase in NMDAR1 immunoreactive protein was found in frontal cortex in the subacute group (P=.036 but not in the acute group (P=.580. Moreover, a significant increase in NMDAR1 was also observed in striatum in both acute (P=.025 and subacute groups (P=.023. However, no significant differences in NMDAR1 in hippocampal formation were observed in either acute or subacute group. The results suggest that an upregulation of NMDA receptor expression may be a consequence of glutamatergic dysfunction induced by METH.

  2. Genotype and toxicity relationships among Hyalella azteca: I. Acute exposure to metals or low pH

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Y.; Guttman, S.I.; Oris, J.T.; Bailer, A.J.

    2000-05-01

    Comparative genotype and toxin interactions at three polymorphic enzyme loci were examined in a laboratory population of amphipods (Hyalella azteca) during acute exposure to cadmium, zinc, copper, lead, or low pH. Significant toxin-genotype interactions were observed using logistic regression to model mortality in ten of 15 analyses. Both stressor-specific and nonspecific modes of selection were observed. In general, low pH selected for different genotypes than those selected by metals, especially zinc. Different modes of selection were also observed when amphipods were exposed to different metals. These results suggest that exposure to low pH would significantly reduce the ability of H. azteca to survive subsequent contamination by metals; exposure to stressors in the reverse order would also compromise a population's chance of survival. A genetic distance analysis showed that the magnitude of genetic differentiation consistently increased among survivors compared with that of the initial populations. These increases in genetic divergence estimates suggest that acute exposure to metals or low pH may have an evolutionarily significant impact on the species. They also suggest that both genotype frequency and genetic distance measures (based on allozyme data) may be used as bioindicators for environmental monitoring programs. Validation of such bioindicators requires an understanding of the population's genetic background, genetic structure, and history.

  3. Residential ozone and lung function in the elderly

    DEFF Research Database (Denmark)

    Braeuner, Elvira V.; Karottki, Dorina Gabriela; Frederiksen, Marie

    2016-01-01

    Ground level ozone arises primarily from traffic, it is a powerful oxidant and its primary target organ is the lung. Most epidemiological studies reporting the health effects of ozone have estimated individual exposure from measurements obtained from outdoor monitors but surrogates of personal...... exposure may not adequately reflect personal exposures. Also, the main focus has been on infants and children. Our purpose was to assess associations between urban background ozone and indoor residential ozone levels as well as to investigate the effects of indoor residential ozone on lung function in 51...... elderly non-smokers. Indoor ozone was measured passively in homes, while urban background outdoor ozone was monitored continuously at a fixed monitoring station located on the roof of the 20-m high university H.C. Ørsteds campus building in a park area. Lung function was measured at baseline as well...

  4. Critical role of matrix metalloproteinase-9 in acute cold exposure-induced stroke in renovascular hypertensive rats.

    Science.gov (United States)

    Li, Chunguang; Li, Xiangpen; Shen, Qingyu; Li, Yi; He, Lei; Li, Mei; Tang, Yamei; Wang, Yidong; He, Qingyu; Peng, Ying

    2013-11-01

    Our objectives are to investigate the role of MMP-9 in cold exposure-induced stroke and assess the preventive effect of doxycycline, a total of 200 rats were assigned to a control group, sham group, 2-kidney, 2-clip (2K-2C) group, and doxycycline-received 2K-2C group (2K-2C+doxy) (N=50, each), and subsequently, each group were randomly assigned to 2 groups: acute cold exposure (ACE) and nonacute cold exposure (NACE) (N=25, each). After the blood pressure was stabilized, rats were maintained on a 12-h light (22°C)/dark (4°C) cycle (ACE group) or a 12-h light (22°C)/dark (22°C) cycle (NACE group) for 3 cycles. The results showed that ACE upregulated Ang II and MMP-9 protein levels in brains and aortas and considerably enhanced stroke incidence in 2K-2C rats. In contrast, doxycycline treatment prevented upregulation of MMP-9 protein expression and activity in brains and aortas in response to ACE and significantly decreased stroke incidence. These findings suggest that cold exposure-induced MMP-9 via activation of RAS might play a critical role in the initiation of cold exposure-induced stroke during chronic hypertension and doxycycline shows protective effects against cold exposure-induced stroke. Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  5. Large-scale analysis of acute ethanol exposure in zebrafish development: a critical time window and resilience.

    Directory of Open Access Journals (Sweden)

    Shaukat Ali

    Full Text Available BACKGROUND: In humans, ethanol exposure during pregnancy causes a spectrum of developmental defects (fetal alcohol syndrome or FAS. Individuals vary in phenotypic expression. Zebrafish embryos develop FAS-like features after ethanol exposure. In this study, we ask whether stage-specific effects of ethanol can be identified in the zebrafish, and if so, whether they allow the pinpointing of sensitive developmental mechanisms. We have therefore conducted the first large-scale (>1500 embryos analysis of acute, stage-specific drug effects on zebrafish development, with a large panel of readouts. METHODOLOGY/PRINCIPAL FINDINGS: Zebrafish embryos were raised in 96-well plates. Range-finding indicated that 10% ethanol for 1 h was suitable for an acute exposure regime. High-resolution magic-angle spinning proton magnetic resonance spectroscopy showed that this produced a transient pulse of 0.86% concentration of ethanol in the embryo within the chorion. Survivors at 5 days postfertilisation were analysed. Phenotypes ranged from normal (resilient to severely malformed. Ethanol exposure at early stages caused high mortality (≥88%. At later stages of exposure, mortality declined and malformations developed. Pharyngeal arch hypoplasia and behavioral impairment were most common after prim-6 and prim-16 exposure. By contrast, microphthalmia and growth retardation were stage-independent. CONCLUSIONS: Our findings show that some ethanol effects are strongly stage-dependent. The phenotypes mimic key aspects of FAS including craniofacial abnormality, microphthalmia, growth retardation and behavioral impairment. We also identify a critical time window (prim-6 and prim-16 for ethanol sensitivity. Finally, our identification of a wide phenotypic spectrum is reminiscent of human FAS, and may provide a useful model for studying disease resilience.

  6. Stratospheric ozone

    Directory of Open Access Journals (Sweden)

    M. Gil

    2006-01-01

    Full Text Available Stratospheric ozone acquired a huge importance two decades ago because of the discovery of strong anomalies above the Antarctica due to gases of anthropogenic origin. From that date, stratosphere has become one of the research lines receiving more funding. A result, an important progress in the development of observational techniques, the understanding of the dynamics of the polar regions and, above all, in understanding of the chemical interactions among the species that influence the chemical-radiative balance of ozone. In this article a general revision is made of the distribution of the ozone in the stratosphere, the mechanisms that determine its equilibrium, the gases that contribute to its destruction, the present situation and the forecast of the health state of the layer.

  7. Molecular and immunological characterization of ragweed (Ambrosia artemisiifolia L. pollen after exposure of the plants to elevated ozone over a whole growing season.

    Directory of Open Access Journals (Sweden)

    Ulrike Kanter

    Full Text Available Climate change and air pollution, including ozone is known to affect plants and might also influence the ragweed pollen, known to carry strong allergens. We compared the transcriptome of ragweed pollen produced under ambient and elevated ozone by 454-sequencing. An enzyme-linked immunosorbent assay (ELISA was carried out for the major ragweed allergen Amb a 1. Pollen surface was examined by scanning electron microscopy and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR, and phenolics were analysed by high-performance liquid chromatography. Elevated ozone had no influence on the pollen size, shape, surface structure or amount of phenolics. ATR-FTIR indicated increased pectin-like material in the exine. Transcriptomic analyses showed changes in expressed-sequence tags (ESTs, including allergens. However, ELISA indicated no significantly increased amounts of Amb a 1 under elevated ozone concentrations. The data highlight a direct influence of ozone on the exine components and transcript level of allergens. As the total protein amount of Amb a 1 was not altered, a direct correlation to an increased risk to human health could not be derived. Additional, the 454-sequencing contributes to the identification of stress-related transcripts in mature pollen that could be grouped into distinct gene ontology terms.

  8. Molecular and immunological characterization of ragweed (Ambrosia artemisiifolia L.) pollen after exposure of the plants to elevated ozone over a whole growing season.

    Science.gov (United States)

    Kanter, Ulrike; Heller, Werner; Durner, Jörg; Winkler, J Barbro; Engel, Marion; Behrendt, Heidrun; Holzinger, Andreas; Braun, Paula; Hauser, Michael; Ferreira, Fatima; Mayer, Klaus; Pfeifer, Matthias; Ernst, Dieter

    2013-01-01

    Climate change and air pollution, including ozone is known to affect plants and might also influence the ragweed pollen, known to carry strong allergens. We compared the transcriptome of ragweed pollen produced under ambient and elevated ozone by 454-sequencing. An enzyme-linked immunosorbent assay (ELISA) was carried out for the major ragweed allergen Amb a 1. Pollen surface was examined by scanning electron microscopy and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and phenolics were analysed by high-performance liquid chromatography. Elevated ozone had no influence on the pollen size, shape, surface structure or amount of phenolics. ATR-FTIR indicated increased pectin-like material in the exine. Transcriptomic analyses showed changes in expressed-sequence tags (ESTs), including allergens. However, ELISA indicated no significantly increased amounts of Amb a 1 under elevated ozone concentrations. The data highlight a direct influence of ozone on the exine components and transcript level of allergens. As the total protein amount of Amb a 1 was not altered, a direct correlation to an increased risk to human health could not be derived. Additional, the 454-sequencing contributes to the identification of stress-related transcripts in mature pollen that could be grouped into distinct gene ontology terms.

  9. Biphasic changes in fetal heart rate variability in preterm fetal sheep developing hypotension after acute on chronic lipopolysaccharide exposure.

    Science.gov (United States)

    Lear, Christopher A; Davidson, Joanne O; Booth, Lindsea C; Wassink, Guido; Galinsky, Robert; Drury, Paul P; Fraser, Mhoyra; Bennet, Laura; Gunn, Alistair J

    2014-08-15

    Perinatal exposure to infection is highly associated with adverse outcomes. Experimentally, acute, severe exposure to gram-negative bacterial lipopolysaccharide (LPS) is associated with increased fetal heart rate variability (FHRV). It is unknown whether FHRV is affected by subclinical infection with or without acute exacerbations. We therefore tested the hypothesis that FHRV would be associated with hypotension after acute on chronic exposure to LPS. Chronically instrumented fetal sheep at 0.7 gestation were exposed to a continuous low-dose LPS infusion (n = 12, 100 ng/kg over 24 h, followed by 250 ng·kg(-1)·24 h(-1) for a further 96 h) or the same volume of saline (n = 10). Boluses of either 1 μg LPS or saline were given at 48, 72, and 96 h. Low-dose infusion was not associated with hemodynamic or FHRV changes. The first LPS bolus was associated with tachycardia and suppression of nuchal electromyographic activity in all fetuses. Seven of twelve fetuses developed hypotension (a fall in mean arterial blood pressure ≥5 mmHg). FHRV was transiently increased only at the onset of hypotension, in association with increased cytokine induction and electroencephalogram suppression. FHRV then fell before the nadir of hypotension, with transient suppression of short-term FHRV. After the second LPS bolus, the hypotension group showed a biphasic pattern of a transient increase in FHRV followed by more prolonged suppression. These findings suggest that infection-related hypotension in the preterm fetus mediates the transient increase in FHRV and that repeated exposure to LPS leads to progressive loss of FHRV.

  10. Sensitivity of a green alga to atrazine is not enhanced by previous acute exposure.

    Science.gov (United States)

    Baxter, Leilan; Brain, Richard; Prosser, Ryan; Solomon, Keith; Hanson, Mark

    2013-10-01

    Exposure to atrazine in small lotic systems can be episodic, with short-term pulses (peaks) followed by lower, decreasing concentrations. Algae and macrophytes recover rapidly from pulsed exposure to atrazine, but reported observations of population response to subsequent exposures are minimal and inconclusive. Consequently, the sensitivity of Pseudokirchneriella subcapitata to atrazine following a pulsed exposure was assessed. Exposure concentrations reflected amplifications of those observed in streams from highly vulnerable watersheds in regions of intense use. Initial pulsed atrazine exposure at 0, 150 or 300 μg/L for 24-h was followed by 72-h exposure to 0, 5, 10, 25, or 50 μg/L. Measured responses were cell density, growth rate, chlorophyll-a, and maximum quantum yield of photosystem II. Algal recovery was rapid and prior pulsed exposure to atrazine did not significantly affect subsequent sensitivity (EC10s, EC25s) for any endpoint, indicating no changes in tolerance at the population level for this species.

  11. SYSTEMIC IMBALANCE OF ESSENTIAL METALS AND CARDIAC GENE EXPRESSION IN RATS FOLLOWING ACUTE PULMONARY ZINC EXPOSURE

    Science.gov (United States)

    We have recently demonstrated that PM containing water-soluble zinc may cause cardiac injury following pulmonary exposure. To investigate if pulmonary zinc exposure causes systemic metal imbalance and direct cardiac effects, we intratracheally (IT) instilled male Wistar Kyoto (WK...

  12. Is hair analysis for dialkyl phosphate metabolites a suitable biomarker for assessing past acute exposure to organophosphate pesticides?

    Science.gov (United States)

    Tsatsakis, A M; Tutudaki, M; Tzatzarakis, M N; Dawson, A; Mohamed, F; Christaki, M; Alegakis, A K

    2012-03-01

    In the present paper, the possibility to use dialkyl phosphate metabolites (DAPs) hair segmental analysis as a biomarker of past acute exposure to organophosphates is examined. Hair samples of four acute poisoning survivors were collected and segmental hair analysis was performed. The total hair samples were divided to 1 cm segments and analysed by gas chromatography-mass spectrometry (GC-MS) for the presence of four DAP metabolites, dimethyl phosphate (DMP), diethyl phosphate (DEP), diethyl thiophosphate (DETP) and diethyl dithiophosphate (DEDTP). Results were examined under the light of pesticide type and time of hair sample collection. Although DAPs were detected all along the hair shaft, higher concentrations (peaks) were detected in the segments proximate to the suicide period. It was also observed that the elevated concentrations of the present metabolites corresponded to the ones produced by the ingested parent compound. Conclusively, measurements of DAPs in the appropriate hair segments of OP-poisoned patients can be used for assessing past acute exposure to organophosphates in certain cases.

  13. Acute Free-Iron Exposure Does Not Explain the Impaired Haemorheology Associated with Haemochromatosis.

    Directory of Open Access Journals (Sweden)

    Antony P McNamee

    Full Text Available Given the severity of the current imbalance between blood donor supply and recipient demand, discarded blood drawn from the routine venesections of haemochromatosis (HFE-HH patients may serve as a valuable alternative source for blood banks and transfusion. We investigated whether functional or biochemical differences existed between HFE-HH and control blood samples, with particular focus upon the haemorheological properties, to investigate the viability of venesected blood being subsequently harvested for blood products.Blood samples were collected from HFE-HH patients undergoing venesection treatment (n = 19 and healthy volunteers (n = 8. Moreover, a second experiment investigated the effects of a dose-response of iron (0, 40, 80, 320 mM FeCl3 on haemorheology in healthy blood samples (n = 7. Dependent variables included basic haematology, iron status, haematocrit, red blood cell (RBC aggregation (native and standardised haematocrit and "aggregability" (RBC tendency to aggregate in a standard aggregating medium; 0.4 L/L haematocrit in a Dx70, and RBC deformability.Indices of RBC deformability were significantly decreased for HFE-HH when compared with healthy controls: RBC deformability was significantly decreased at 1-7 Pa (p < 0.05, and the shear stress required for half maximal deformability was significantly increased (p < 0.05 for HFE-HH. RBC aggregation in plasma was significantly increased (p < 0.001 for HFE-HH, although when RBC were suspended in plasma-free Dx70 no differences were detected. No differences in RBC deformability or RBC aggregation/aggregability were detected when healthy RBC were incubated with varying dose of FeCl3.HFE-HH impairs the haemorheological properties of blood; however, RBC aggregability was similar between HFE-HH and controls when cells were suspended in a plasma-free medium, indicating that plasma factor(s may explain the altered haemorheology in HFE-HH patients. Acute exposure to elevated iron levels does

  14. The use of self-reported symptoms as a proxy for acute organophosphate poisoning after exposure to chlorpyrifos 50 % plus cypermethrin 5 % among Nepali farmers

    DEFF Research Database (Denmark)

    Kofod, Dea Haagensen; Jørs, Erik; Varma, Anshu

    2016-01-01

    cholinesterase (PchE) activity, in addition to the symptoms, when assessing occupational acute pesticide poisoning. This study evaluated self-reported symptoms as a proxy for acute organophosphate poisoning among Nepali farmers by examining self-reported acute organophosphate poisoning symptoms and PchE activity......%: moderately hazardous) spray session or a 2-h placebo spray session, and after 7 days' washout, the farmers were assigned to the other spray session. Before and after each spray session farmers were interviewed about acute organophosphate poisoning symptoms and PchE activity was measured. Analyses were...... symptoms among the farmers regardless of organophosphate exposure or poisoning. Thus, self-reported acute organophosphate symptoms seem to be a poor proxy for acute organophosphate poisoning as the occurrence of these symptoms is not necessarily associated with acute organophosphate poisoning. TRIAL...

  15. Quantifying fish swimming behavior in response to acute exposure of aqueous copper using computer assisted video and digital image analysis

    Science.gov (United States)

    Calfee, Robin D.; Puglis, Holly J.; Little, Edward E.; Brumbaugh, William G.; Mebane, Christopher A.

    2016-01-01

    Behavioral responses of aquatic organisms to environmental contaminants can be precursors of other effects such as survival, growth, or reproduction. However, these responses may be subtle, and measurement can be challenging. Using juvenile white sturgeon (Acipenser transmontanus) with copper exposures, this paper illustrates techniques used for quantifying behavioral responses using computer assisted video and digital image analysis. In previous studies severe impairments in swimming behavior were observed among early life stage white sturgeon during acute and chronic exposures to copper. Sturgeon behavior was rapidly impaired and to the extent that survival in the field would be jeopardized, as fish would be swept downstream, or readily captured by predators. The objectives of this investigation were to illustrate protocols to quantify swimming activity during a series of acute copper exposures to determine time to effect during early lifestage development, and to understand the significance of these responses relative to survival of these vulnerable early lifestage fish. With mortality being on a time continuum, determining when copper first affects swimming ability helps us to understand the implications for population level effects. The techniques used are readily adaptable to experimental designs with other organisms and stressors.

  16. Risk Analysis of Acute Or Chronic Exposure to Arsenic of the Inhabitants in a District of Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Cristina Vázquez

    2016-09-01

    Full Text Available The arsenic occurrence in the water constitutes a serious world health concern due to its toxicity. Depending on the intensity and duration of exposure, this element can be acutely lethal or may have a wide range of health effects in humans and animals. In Argentina, the origin of arsenic is mainly natural, and related to different geological processes. The Argentinean concern about arsenic and its influence on human health dates back to the previous century. The disease ascribed to arsenic contamination was called ‘chronic regional endemic hydroarsenism’. It is produced by the consumption of water with high levels of this element. In our study, we focused in La Matanza district, a very populated site in the Buenos Aires Province. An increasing concern of the inhabitants of the area regarding health problems was detected. In order to establish a full view of arsenic exposure in the area, several matrices and targets were analyzed. As matrices, water and soil samples were analyzed. As targets, canine and human hair was studied. The aim of this study was to investigate acute and chronically exposure to arsenic of La Matanza inhabitants.

  17. Effects of acute exercise on fear extinction in rats and exposure therapy in humans: Null findings from five experiments.

    Science.gov (United States)

    Jacquart, Jolene; Roquet, Rheall F; Papini, Santiago; Powers, Mark B; Rosenfield, David; Smits, Jasper A J; Monfils, Marie-H

    2017-08-01

    Exposure therapy is an established learning-based intervention for the treatment of anxiety disorders with an average response rate of nearly 50%, leaving room for improvement. Emerging strategies to enhance exposure therapy in humans and fear extinction retention in animal models are primarily pharmacological. These approaches are limited as many patients report preferring non-pharmacological approaches in therapy. With general cognitive enhancement effects, exercise has emerged as a plausible non-pharmacological augmentation strategy. The present study tested the hypothesis that fear extinction and exposure therapy would be enhanced by a pre-training bout of exercise. We conducted four experiments with rats that involved a standardized conditioning and extinction paradigm and a manipulation of exercise. In a fifth experiment, we manipulated vigorous-intensity exercise prior to a standardized virtual reality exposure therapy session among adults with fear of heights. In experiments 1-4, exercise did not facilitate fear extinction, long-term memory, or fear relapse tests. In experiment 5, human participants showed an overall reduction in fear of heights but exercise did not enhance symptom improvement. Although acute exercise prior to fear extinction or exposure therapy, as operationalized in the present 5 studies, did not enhance outcomes, these results must be interpreted within the context of a broader literature that includes positive findings. Taken all together, this suggests that more research is necessary to identify optimal parameters and key individual differences so that exercise can be implemented successfully to treat anxiety disorders. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. The effects of acute waterborne exposure to sublethal concentrations of molybdenum on the stress response in rainbow trout, Oncorhynchus mykiss.

    Directory of Open Access Journals (Sweden)

    Chelsea D Ricketts

    Full Text Available To determine if molybdenum (Mo is a chemical stressor, fingerling and juvenile rainbow trout (Oncorhynchus mykiss were exposed to waterborne sodium molybdate (0, 2, 20, or 1,000 mg l-1 of Mo and components of the physiological (plasma cortisol, blood glucose, and hematocrit and cellular (heat shock protein [hsp] 72, hsp73, and hsp90 in the liver, gills, heart, and erythrocytes and metallothionein [MT] in the liver and gills stress responses were measured prior to initiation of exposure and at 8, 24, and 96 h. During the acute exposure, plasma cortisol, blood glucose, and hematocrit levels remained unchanged in all treatments. Heat shock protein 72 was not induced as a result of exposure and there were no detectable changes in total hsp70 (72 and 73, hsp90, and MT levels in any of the tissues relative to controls. Both fingerling and juvenile fish responded with similar lack of apparent sensitivity to Mo exposure. These experiments demonstrate that exposure to waterborne Mo of up to 1,000 mg l(-1 did not activate a physiological or cellular stress response in fish. Information from this study suggests that Mo water quality guidelines for the protection of aquatic life are highly protective of freshwater fish, namely rainbow trout.

  19. Acute chlorine gas exposure produces transient inflammation and a progressive alteration in surfactant composition with accompanying mechanical dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Massa, Christopher B.; Scott, Pamela; Abramova, Elena; Gardner, Carol; Laskin, Debra L.; Gow, Andrew J., E-mail: Gow@rci.rutgers.edu

    2014-07-01

    Acute Cl{sub 2} exposure following industrial accidents or military/terrorist activity causes pulmonary injury and severe acute respiratory distress. Prior studies suggest that antioxidant depletion is important in producing dysfunction, however a pathophysiologic mechanism has not been elucidated. We propose that acute Cl{sub 2} inhalation leads to oxidative modification of lung lining fluid, producing surfactant inactivation, inflammation and mechanical respiratory dysfunction at the organ level. C57BL/6J mice underwent whole-body exposure to an effective 60 ppm-hour Cl{sub 2} dose, and were euthanized 3, 24 and 48 h later. Whereas pulmonary architecture and endothelial barrier function were preserved, transient neutrophilia, peaking at 24 h, was noted. Increased expression of ARG1, CCL2, RETLNA, IL-1b, and PTGS2 genes was observed in bronchoalveolar lavage (BAL) cells with peak change in all genes at 24 h. Cl{sub 2} exposure had no effect on NOS2 mRNA or iNOS protein expression, nor on BAL NO{sub 3}{sup −} or NO{sub 2}{sup −}. Expression of the alternative macrophage activation markers, Relm-α and mannose receptor was increased in alveolar macrophages and pulmonary epithelium. Capillary surfactometry demonstrated impaired surfactant function, and altered BAL phospholipid and surfactant protein content following exposure. Organ level respiratory function was assessed by forced oscillation technique at 5 end expiratory pressures. Cl{sub 2} exposure had no significant effect on either airway or tissue resistance. Pulmonary elastance was elevated with time following exposure and demonstrated PEEP refractory derecruitment at 48 h, despite waning inflammation. These data support a role for surfactant inactivation as a physiologic mechanism underlying respiratory dysfunction following Cl{sub 2} inhalation. - Highlights: • Effect of 60 ppm*hr Cl{sub 2} gas on lung inflammation and mechanical function examined. • Pulmonary inflammation is transient and minor.

  20. Slow and stepped re-warming after acute low temperature exposure do not improve survival of Drosophila melanogaster larvae.

    Science.gov (United States)

    Sinclair, Brent J; Rajamohan, Arun

    2008-01-01

    We tested that hypothesis that slow re-warming rates would improve the ability of Drosophila melanogaster Meigen larvae to survive acute low temperature exposure. Four larval stages (1(st), 2(nd), 3(rd) instars and wandering stage 3(rd) instars) of four wild-type strains were exposed to -7 degrees C for periods of time expected to result in 90 % mortality. Larvae were then either directly transferred to their rearing temperature (21 degrees C), or returned to this temperature in a stepwise fashion (pausing at 0 and 15 degrees C) or by slow warming at 1 or 0.1 degrees C/min. We observed a reduced rapid cold-hardening effect and no general increase in survival of acute chilling in larvae re-warmed in a stepwise or slow fashion, and hypothesise that slow re-warming may result in accumulation of further chill injuries.

  1. The Antarctic Ozone Hole

    Science.gov (United States)

    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…

  2. Short-term exposure to ambient particulate matter and emergency ambulance dispatch for acute illness in Japan.

    Science.gov (United States)

    Tasmin, Saira; Ueda, Kayo; Stickley, Andrew; Yasumoto, Shinya; Phung, Vera Ling Hui; Oishi, Mizuki; Yasukouchi, Shusuke; Uehara, Yamato; Michikawa, Takehiro; Nitta, Hiroshi

    2016-10-01

    Short-term exposure to air pollution may be linked to negative health outcomes that require an emergency medical response. However, few studies have been undertaken on this phenomenon to date. The aim of this study therefore was to examine the association between short-term exposure to ambient suspended particulate matter (SPM) and emergency ambulance dispatches (EADs) for acute illness in Japan. Daily EAD data, daily mean SPM and meteorological data were obtained for four prefectures in the Kanto region of Japan for the period from 2007 to 2011. The area-specific association between daily EAD for acute illness and SPM was explored using generalized linear models while controlling for ambient temperature, relative humidity, seasonality, long-term trends, day of the week and public holidays. Stratified analyses were conducted to evaluate the modifying effects of age, sex and medical conditions. Area-specific estimates were combined using meta-analyses. For the total study period the mean level of SPM was 23.7μg/m(3). In general, higher SPM was associated with a significant increase in EAD for acute illness [estimated pooled relative risk (RR): 1.008, 95% CI: 1.007 to 1.010 per 10μg/m(3) increase in SPM at lag 0-1]. The effects of SPM on EAD for acute illness were significantly greater for moderate/mild medical conditions (e.g. cases that resulted in 3weeks hospitalization or which resulted in death). Using EAD data, this study has shown the adverse health effects of ambient air pollution. This highlights the importance of reducing the level of air pollution in order to maintain population health and well-being.

  3. Effects of acute versus repeated cocaine exposure on the expression of endocannabinoid signaling-related proteins in the mouse cerebellum

    Directory of Open Access Journals (Sweden)

    Ana ePalomino

    2014-03-01

    Full Text Available Growing awareness of cerebellar involvement in addiction is based on the cerebellum’s intermediary position between motor and reward, potentially acting as an interface between motivational and cognitive functions. Here, we examined the impact of acute and repeated cocaine exposure on the two main signaling systems in the mouse cerebellum: the endocannabinoid (eCB and glutamate systems. To this end, we investigated whether eCB signaling-related gene and protein expression (CB1 receptors and enzymes that produce (DAGLα/β and NAPE-PLD and degrade (MAGL and FAAH eCB were altered. In addition, we analyzed the gene expression of relevant components of the glutamate signaling system (glutamate synthesizing enzymes LGA and KGA, mGluR3/5 metabotropic receptors, and NR1/2A/2B/2C-NMDA and GluR1/2/3/4-AMPA ionotropic receptor subunits and the gene expression of tyrosine hydroxylase (TH, the rate-limiting enzyme in catecholamine biosynthesis, because noradrenergic terminals innervate the cerebellar cortex. Results indicated that acute cocaine exposure decreased DAGLα expression, suggesting a down-regulation of 2-AG production, as well as gene expression of TH, KGA, mGluR3 and all ionotropic receptor subunits analyzed in the cerebellum. The acquisition of conditioned locomotion and sensitization after repeated cocaine exposure were associated with an increased NAPE-PLD/FAAH ratio, suggesting enhanced anandamide production, and a decreased DAGLβ/MAGL ratio, suggesting decreased 2-AG generation. Repeated cocaine also increased LGA gene expression but had no effect on glutamate receptors. These findings indicate that acute cocaine modulates the expression of the eCB and glutamate systems. Repeated cocaine results in normalization of glutamate receptor expression, although sustained changes in eCB is observed. We suggest that cocaine-induced alterations to cerebellar eCB should be considered when analyzing the adaptations imposed by psychostimulants that

  4. Long-term ethanol exposure decreases the endotoxin-induced hepatic acute phase response in rats

    DEFF Research Database (Denmark)

    Glavind, Emilie; Vilstrup, Hendrik; Grønbaek, Henning

    2017-01-01

    -fed rats showed either no liver histopathological changes or varying degrees of steatosis. Ethanol feeding decreased the spontaneous liver mRNA expression of the prevailing acute phase protein alpha-2-macroglobulin by 30% (Ptumor necrosis factor...... an induced acute phase response is impaired in long-term ethanol-fed rats. METHODS: For six weeks, rats were either fed a Lieber-DeCarli ethanol-containing (36% as calories) liquid diet ad libitum or calorically pair-fed. Then, the rats were injected intraperitoneally with a low-dose of lipopolysaccharide...... (LPS) (0.5 mg/kg) to induce an acute phase response. Two hours after LPS, we measured the plasma concentrations of an array of inflammatory cytokines. Twenty-four hours after LPS, we measured the hepatic mRNA expression and serum concentrations of prominent rat acute phase proteins. RESULTS: Ethanol...

  5. Differences in inflammation and acute phase response but similar genotoxicity in mice following pulmonary exposure to graphene oxide and reduced graphene oxide

    DEFF Research Database (Denmark)

    Bengtson, Stefan; Knudsen, KB; Kyjovska, ZO

    2017-01-01

    the lowest dose was evaluated. GO induced a strong acute inflammatory response together with a pulmonary (Serum-Amyloid A, Saa3) and hepatic (Saa1) acute phase response. rGO induced less acute, but a constant and prolonged inflammation up to day 90. Lung histopathology showed particle agglomerates at day 90...... without signs of fibrosis. In addition, DNA damage in BAL cells was observed across time points and doses for both GO and rGO. In conclusion, pulmonary exposure to GO and rGO induced inflammation, acute phase response and genotoxicity but no fibrosis.......We investigated toxicity of 2-3 layered >1 μm sized graphene oxide (GO) and reduced graphene oxide (rGO) in mice following single intratracheal exposure with respect to pulmonary inflammation, acute phase response (biomarker for risk of cardiovascular disease) and genotoxicity. In addition, we...

  6. Development of ozone sterilization system based microcontroller for E. Coli bacteria sterilization

    Science.gov (United States)

    Eko Fahrudin, Arfan; Endarko; Vijai Nasrulloh, Amar; Sari, Nurma

    2017-05-01

    It has been created microcontroller-based ozone sterilization system which is used for E. Coli bacteria sterilization. The created system consists of a neon sign transformer, corona electrode, ozone gas chamber container and ozone gas metering systems. Neon sign transformer and corona electrode are then assembled into an ozone generator that works on the principle of corona discharge. The use of ozone generators is controlled by microcontroller system. Ozone gas is produced by ozone generators which housed in a chamber and equipped by ozone gas indicator. The results of ozone gas effect testing in E. Coli with varied exposure of 15, 30 and 45 minutes showed the decrease number of E. Coli colonies of tested bacteria samples compared to the control sample without ozone gas exposure.

  7. Aging and episodic ozone exposure in Brown Norway rats: Effects on heart rate, core temperature, pulmonary function, and expression of serum biomarkers.

    Science.gov (United States)

    Ozone (03) is an air pollutant that is associated with cardiovascular and respiratory diseases. The aged population is considered to be more sensitive to pollutants such as 03;however, relatively few studies have demonstrated increased susceptibility in aged or senescent animal m...

  8. High Fructose/High Fat Diets Mediate Changes in Protein Carbonyl Content in the Rat Brain With and Without Ozone Exposure

    Science.gov (United States)

    The consumption of diets rich in fat or fructose have been correlated to a rise in type-2 diabetes and obesity. These diet-induced physiological changes have been shown previously to cause an increase in responsiveness to air pollutants such as ozone (03). 03 is a pervasive air p...

  9. Does interspecific competition alter effects of early season ozone exposure on plants from wet grasslands? Results of a three-year experiment in open-top chambers

    NARCIS (Netherlands)

    Tonneijck, A.E.G.; Franzaring, J.; Brouwer, G.; Metselaar, K.; Dueck, T.A.

    2004-01-01

    Chronic effects of ozone on wet grassland species early in the growing season might be altered by interspecific competition. Individual plants of Holcus lanatus, Lychnis flos-cuculi, Molinia caerulea and Plantago lanceolata were grown in monocultures and in mixed cultures with Agrostis capillaris. M

  10. Effects of Acute Oral 5-aminotetrazole (5-AT) Exposure to Rats (Rattus norvegicus)

    Science.gov (United States)

    2015-02-12

    Micronucleus Assay (MNA) Male rats from the 5-AT study (three highest dose groups and the vehicle control) were tested for DNA damage in their peripheral...Dose Test (Sub-acute Study) - Sperm Collection and Analysis 09/25/2013 10/07/2013 14-Day Repeated Dose Test (Sub-acute Study) - Micronucleus Assay...2015 Prepared by: Valerie H Adams, Ph.D. Approved for public release; distribution unlimited. Specialty: 500C Toxicity Test Toxicity Report No. S

  11. Renal effects of acute exposure to toluene. A controlled clinical trial

    DEFF Research Database (Denmark)

    Nielsen, H K; Krusell, Lars Romer; Bælum, Jesper

    1985-01-01

    Urinary excretion rates of beta 2-microglobulin and albumin were measured in 43 male printing trade workers and 43 age-matched male controls before and during exposure to toluene, 382 mg/m3, for 6 1/2 hours in a climate chamber. There were no significant changes in renal excretion rates of albumin...... and beta 2-microglobulin during toluene exposure indicating that no causal relationship exists between moderate exposure to organic solvents and renal injury....

  12. Probabilistic assessment of the cumulative dietary acute exposure of the population of Denmark to organophosphorus and carbamate pesticides

    DEFF Research Database (Denmark)

    Jensen, Bodil Hamborg; Petersen, Annette; Christensen, Tue

    2009-01-01

    Organophosphorus and carbamate pesticides are acetylcholinesterase-inhibiting pesticides and as such have a common mode of action. We assessed the cumulative acute exposure of the population of Denmark to 25 organophosphorus and carbamate pesticide residues from the consumption of fruit, vegetables...... the nationwide dietary survey conducted in 2000-2002. Contributions from 43 commodities were included in the calculations. We used the relative potency factor (RPF) approach to normalize the toxicity of the various organophosphorus and carbamate pesticides to the two index compounds chlorpyriphos...

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

    Science.gov (United States)

    Paoletti, Elena; Ferrara, Anna Maria; Calatayud, Vicent; Cerveró, Júlia; Giannetti, Fabio; Sanz, María José; Manning, William J

    2009-03-01

    Ozone-like visible injury was detected on Hibiscus syriacus plants used as ornamental hedges. Weekly spray of the antiozonant ethylenediurea (EDU, 300ppm) 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 (+30ppb) 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.

  14. Probabilistic acute dietary exposure assessments to captan and tolylfluanid using several European food consumption and pesticide concentration databases

    DEFF Research Database (Denmark)

    Boon, Polly E.; Svensson, Kettil; Moussavian, Shahnaz

    2009-01-01

    Probabilistic dietary acute exposure assessments of captan and tolylfluanid were performed for the populations of the Czech Republic, Denmark, Italy, the Netherlands and Sweden. The basis for these assessments was national databases for food consumption and pesticide concentration data harmonised...... at the level of raw agricultural commodity. Data were obtained from national food consumption surveys and national monitoring programmes and organised in an electronic platform of databases connected to probabilistic software. The exposure assessments were conducted by linking national food consumption data...... to national food consumption surveys. In this way it is possible to exchange or merge concentration data between countries in situations of data scarcity. This electronic platform in connection with probabilistic software can be seen as a prototype of a data warehouse, including a harmonised approach...

  15. Quantification of optic disc edema during exposure to high altitude shows no correlation to acute mountain sickness.

    Directory of Open Access Journals (Sweden)

    Gabriel Willmann

    Full Text Available BACKGROUND: The study aimed to quantify changes of the optic nerve head (ONH during exposure to high altitude and to assess a correlation with acute mountain sickness (AMS. This work is related to the Tuebingen High Altitude Ophthalmology (THAO study. METHODOLOGY/PRINCIPAL FINDINGS: A confocal scanning laser ophthalmoscope (cSLO, Heidelberg Retina Tomograph, HRT3® was used to quantify changes at the ONH in 18 healthy participants before, during and after rapid ascent to high altitude (4559 m. Slitlamp biomicroscopy was used for clinical optic disc evaluation; AMS was assessed with Lake Louise (LL and AMS-cerebral (AMS-c scores; oxygen saturation (SpO₂ and heart rate (HR were monitored. These parameters were used to correlate with changes at the ONH. After the first night spent at high altitude, incidence of AMS was 55% and presence of clinical optic disc edema (ODE 79%. Key stereometric parameters of the HRT3® used to describe ODE (mean retinal nerve fiber layer [RNFL] thickness, RNFL cross sectional area, optic disc rim volume and maximum contour elevation changed significantly at high altitude compared to baseline (p<0.05 and were consistent with clinically described ODE. All changes were reversible in all participants after descent. There was no significant correlation between parameters of ODE and AMS, SpO₂ or HR. CONCLUSIONS/SIGNIFICANCE: Exposure to high altitude leads to reversible ODE in the majority of healthy subjects. However, these changes did not correlate with AMS or basic physiologic parameters such as SpO₂ and HR. For the first time, a quantitative approach has been used to assess these changes during acute, non-acclimatized high altitude exposure. In conclusion, ODE presents a reaction of the body to high altitude exposure unrelated to AMS.

  16. Quantification of Optic Disc Edema during Exposure to High Altitude Shows No Correlation to Acute Mountain Sickness

    Science.gov (United States)

    Willmann, Gabriel; Fischer, M. Dominik; Schatz, Andreas; Schommer, Kai; Messias, Andre; Zrenner, Eberhart; Bartz-Schmidt, Karl U.; Gekeler, Florian

    2011-01-01

    Background The study aimed to quantify changes of the optic nerve head (ONH) during exposure to high altitude and to assess a correlation with acute mountain sickness (AMS). This work is related to the Tuebingen High Altitude Ophthalmology (THAO) study. Methodology/Principal Findings A confocal scanning laser ophthalmoscope (cSLO, Heidelberg Retina Tomograph, HRT3®) was used to quantify changes at the ONH in 18 healthy participants before, during and after rapid ascent to high altitude (4559 m). Slitlamp biomicroscopy was used for clinical optic disc evaluation; AMS was assessed with Lake Louise (LL) and AMS-cerebral (AMS-c) scores; oxygen saturation (SpO2) and heart rate (HR) were monitored. These parameters were used to correlate with changes at the ONH. After the first night spent at high altitude, incidence of AMS was 55% and presence of clinical optic disc edema (ODE) 79%. Key stereometric parameters of the HRT3® used to describe ODE (mean retinal nerve fiber layer [RNFL] thickness, RNFL cross sectional area, optic disc rim volume and maximum contour elevation) changed significantly at high altitude compared to baseline (p<0.05) and were consistent with clinically described ODE. All changes were reversible in all participants after descent. There was no significant correlation between parameters of ODE and AMS, SpO2 or HR. Conclusions/Significance Exposure to high altitude leads to reversible ODE in the majority of healthy subjects. However, these changes did not correlate with AMS or basic physiologic parameters such as SpO2 and HR. For the first time, a quantitative approach has been used to assess these changes during acute, non-acclimatized high altitude exposure. In conclusion, ODE presents a reaction of the body to high altitude exposure unrelated to AMS. PMID:22069483

  17. Probabilistic acute risk assessment of cumulative exposure to organophosphorus and carbamate pesticides from dietary vegetables and fruits in Shanghai populations.

    Science.gov (United States)

    Li, Fan; Yuan, Yaqun; Meng, Pai; Wu, Min; Li, Shuguang; Chen, Bo

    2017-05-01

    Organophosphorus pesticides (OPs) and carbamate pesticides (CPs) are among the most widely used pesticides in China, playing a major role in protecting agricultural commodities. In this study, we determined the cumulative acute exposure to OPs and CPs of Shanghai residents from vegetables and fruits (VFs). The food consumption data were obtained from the Shanghai Food Consumption Survey (SHFCS) of 2012-14 including a total of 1973 participants aged 2-90 years. The pesticide residue data were obtained from the Shanghai monitoring programme during 2008-11 with 34 organophosphates and 11 carbamates analysed in a total of 5335 samples of VFs. A probabilistic approach was performed as recommended by the EFSA, using the optimistic model with non-detects set as zero and with processing factors (PFs) being used and the pessimistic model with non-detects replaced by limit of detection (LOD) and without PFs. We used the relative potency factor (RPF) method to normalise the various pesticides to the index compound (IC) of methamidophos and chlorpyrifos separately. Only in the pessimistic model using methamidophos as the IC was there was small risk of exposure exceeding the ARfD (3 µg kg(-)(1) bw day(-)(1)) in the populations of preschool children (0.029%), school-age children (0.022%) and adults (0.002%). There were no risk of exposure exceeding the ARfD of methamidophos in the optimistic model and of chlorpyrifos (100 µg kg(-)(1) bw day(-)(1)) in both optimistic and pessimistic models in all three populations. Considering the Chinese habits of overwhelmingly eating processed food (vegetables being cooked, and fruits being washed or peeled), we conclude that little acute risk was found for the exposure to VF-sourced OPs and CPs in Shanghai.

  18. Earth's Endangered Ozone

    Science.gov (United States)

    Panofsky, Hans A.

    1978-01-01

    Included are (1) a discussion of ozone chemistry; (2) the effects of nitrogen fertilizers, fluorocarbons, and high level aircraft on the ozone layer; and (3) the possible results of a decreasing ozone layer. (MR)

  19. Acute and chronic effects from pulse exposure of D. magna to silver and copper oxide nanoparticles

    DEFF Research Database (Denmark)

    Sørensen, Sara Nørgaard; Lützhøft, Hans-Christian Holten; Rasmussen, Rose

    2016-01-01

    Aquatic toxicity testing of nanoparticles (NPs) is challenged by their dynamic behavior in test suspensions. The resulting difficulties in controlling and characterizing exposure concentrations are detrimental to the generation of concentration-response data needed for hazard identification of NPs...... concentrations during 1–3 h pulses than for 24–48 h continuous exposures. For AgNPs, preparation of test suspensions in medium 24 h before toxicity testing (aging) increased stability during the short-term pulses. In pulse tests, organisms were exposed to the test materials, AgNPs and CuONPs for 1, 2 and 3 h...... (observed after 48 h post-exposure) as 24 h continuous exposure, as evidenced by overlapping 95% confidence intervals of EC50-values. In the 21 d post-exposure period, no trends in mortality or body length were identified. AgNP and AgNO3 pulses had no effect on the number of moltings, days to first live...

  20. Moderate (2%, v/v Ethanol Feeding Alters Hepatic Wound Healing after Acute Carbon Tetrachloride Exposure in Mice

    Directory of Open Access Journals (Sweden)

    Krutika T. Deshpande

    2016-01-01

    Full Text Available Wound healing consists of three overlapping phases: inflammation, proliferation, and matrix synthesis and remodeling. Prolonged alcohol abuse can cause liver fibrosis due to deregulated matrix remodeling. Previous studies demonstrated that moderate ethanol feeding enhances liver fibrogenic markers and frank fibrosis independent of differences in CCl4-induced liver injury. Our objective was to determine whether or not other phases of the hepatic wound healing response were affected by moderate ethanol after CCl4 exposure. Mice were fed moderate ethanol (2% v/v for two days and then were exposed to CCl4 and euthanized 24–96 h later. Liver injury was not different between pair- and ethanol-fed mice; however, removal of necrotic tissue was delayed after CCl4-induced liver injury in ethanol-fed mice. Inflammation, measured by TNFα mRNA and protein and hepatic Ly6c transcript accumulation, was reduced and associated with enhanced hepatocyte apoptosis after ethanol feeding. Hepatocytes entered the cell cycle equivalently in pair- and ethanol-fed mice after CCl4 exposure, but hepatocyte proliferation was prolonged in livers from ethanol-fed mice. CCl4-induced hepatic stellate cell activation was increased and matrix remodeling was prolonged in ethanol-fed mice compared to controls. Taken together, moderate ethanol affected each phase of the wound healing response to CCl4. These data highlight previously unknown effects of moderate ethanol exposure on hepatic wound healing after acute hepatotoxicant exposure.

  1. Moderate (2%, v/v) Ethanol Feeding Alters Hepatic Wound Healing after Acute Carbon Tetrachloride Exposure in Mice.

    Science.gov (United States)

    Deshpande, Krutika T; Liu, Shinlan; McCracken, Jennifer M; Jiang, Lu; Gaw, Ta Ehpaw; Kaydo, Lindsey N; Richard, Zachary C; O'Neil, Maura F; Pritchard, Michele T

    2016-01-06

    Wound healing consists of three overlapping phases: inflammation, proliferation, and matrix synthesis and remodeling. Prolonged alcohol abuse can cause liver fibrosis due to deregulated matrix remodeling. Previous studies demonstrated that moderate ethanol feeding enhances liver fibrogenic markers and frank fibrosis independent of differences in CCl₄-induced liver injury. Our objective was to determine whether or not other phases of the hepatic wound healing response were affected by moderate ethanol after CCl₄ exposure. Mice were fed moderate ethanol (2% v/v) for two days and then were exposed to CCl₄ and euthanized 24-96 h later. Liver injury was not different between pair- and ethanol-fed mice; however, removal of necrotic tissue was delayed after CCl₄-induced liver injury in ethanol-fed mice. Inflammation, measured by TNFα mRNA and protein and hepatic Ly6c transcript accumulation, was reduced and associated with enhanced hepatocyte apoptosis after ethanol feeding. Hepatocytes entered the cell cycle equivalently in pair- and ethanol-fed mice after CCl₄ exposure, but hepatocyte proliferation was prolonged in livers from ethanol-fed mice. CCl₄-induced hepatic stellate cell activation was increased and matrix remodeling was prolonged in ethanol-fed mice compared to controls. Taken together, moderate ethanol affected each phase of the wound healing response to CCl₄. These data highlight previously unknown effects of moderate ethanol exposure on hepatic wound healing after acute hepatotoxicant exposure.

  2. Contributing Factors for Acute Illness/Injury from Childhood Pesticide Exposure in North Carolina, USA, 2007–2013

    Directory of Open Access Journals (Sweden)

    Nirmalla Barros

    2016-02-01

    Full Text Available Between 2007 and 2013, there were 685 events with evidence of a relationship between pesticide exposure and acute illness/injury among persons less than 18 years old in North Carolina (United States. Median age of children affected was 4.3 years (range: 0.2–17.9. Distribution by gender was similar across all age groups. One fatality and four high severity events were observed. The greatest proportion (42% of events had ocular exposures, followed by dermal (25% and inhalation (18% exposures. When more than one route of exposure occurred, dermal and ocular routes were the most common (46%. Almost all events took place indoors and 32 events involved contact with pets. Insecticides (53% and insect repellants (31% were the most frequent agents contributing to these events. Manual application of pesticides contributed to the greatest number of events (25%, while application through a pressurized can and use of a trigger pump were involved in 21% and 15% of events, respectively. Additional contributors were due to inappropriate storage of pesticides and improper use of the pesticide. These contributing factors can be removed or minimized if pesticides are stored outside the residence or out of the reach of children and pets, and adequate ventilation is ensured whenever pesticides are applied.

  3. Probabilistic acute dietary exposure assessments to captan and tolylfluanid using several European food consumption and pesticide concentration databases.

    Science.gov (United States)

    Boon, Polly E; Svensson, Kettil; Moussavian, Shahnaz; van der Voet, Hilko; Petersen, Annette; Ruprich, Jiri; Debegnach, Francesca; de Boer, Waldo J; van Donkersgoed, Gerda; Brera, Carlo; van Klaveren, Jacob D; Busk, Leif

    2009-12-01

    Probabilistic dietary acute exposure assessments of captan and tolylfluanid were performed for the populations of the Czech Republic, Denmark, Italy, the Netherlands and Sweden. The basis for these assessments was national databases for food consumption and pesticide concentration data harmonised at the level of raw agricultural commodity. Data were obtained from national food consumption surveys and national monitoring programmes and organised in an electronic platform of databases connected to probabilistic software. The exposure assessments were conducted by linking national food consumption data either (1) to national pesticide concentration data or (2) to a pooled database containing all national pesticide concentration data. We show that with this tool national exposure assessments can be performed in a harmonised way and that pesticide concentrations of other countries can be linked to national food consumption surveys. In this way it is possible to exchange or merge concentration data between countries in situations of data scarcity. This electronic platform in connection with probabilistic software can be seen as a prototype of a data warehouse, including a harmonised approach for dietary exposure modelling.

  4. Enhanced biosynthesis of quercetin occurs as A photoprotective measure in Lycopersicon esculentum mill. under Acute UV-B exposure

    Directory of Open Access Journals (Sweden)

    Abhilasha Shourie

    2014-06-01

    Full Text Available Lycopersicon esculentum respond to UV-B by enhanced synthesis of flavonoid quercetin, a strong antioxidant that helps the plants to well acclimatize to UV-B stress. Three weeks old plants of L. esculentum were subjected to acute UV-B irradiation for 20, 40 and 60 minutes daily until 28 days and analyzed for the morphological and biochemical changes. UV-B exposure for 40 and 60 minutes considerably affected the growth and biomass of L. esculentum. The leaves were deformed, developed chlorosis and abscised early as compared to the unexposed plants. Biomass declined by 35% and total chlorophyll decreased by 24.7% due to disintegration of chloroplasts. Enhancement was seen in the content of carotenoids, anthocyanins and