WorldWideScience

Sample records for air contamination due

  1. Environmental contamination due to shale gas development.

    Science.gov (United States)

    Annevelink, M P J A; Meesters, J A J; Hendriks, A J

    2016-04-15

    Shale gas development potentially contaminates both air and water compartments. To assist in governmental decision-making on future explorations, we reviewed scattered information on activities, emissions and concentrations related to shale gas development. We compared concentrations from monitoring programmes to quality standards as a first indication of environmental risks. Emissions could not be estimated accurately because of incomparable and insufficient data. Air and water concentrations range widely. Poor wastewater treatment posed the highest risk with concentrations exceeding both Natural Background Values (NBVs) by a factor 1000-10,000 and Lowest Quality Standards (LQSs) by a factor 10-100. Concentrations of salts, metals, volatile organic compounds (VOCs) and hydrocarbons exceeded aquatic ecotoxicological water standards. Future research must focus on measuring aerial and aquatic emissions of toxic chemicals, generalisation of experimental setups and measurement technics and further human and ecological risk assessment.

  2. Air Contamination With Fungals In Museum

    Science.gov (United States)

    Scarlat, Iuliana; Haiducu, Maria; Stepa, Raluca

    2015-07-01

    The aim of the studies was to determine the level and kind of fungal contamination of air in museum, deposits patrimony, restoration and conservation laboratories and their effects on health of workers. Microbiological air purity was measured with a SAS-100 Surface Air System impactor. The fungal contamination was observed in all 54 rooms where we made determinations. The highest levels of fungal were recorded at rooms with hygroscopic patrimony objects, eg carpets, chairs, upholstered chairs, books etc. The most species identified included under common allergens: Aspergillus, Penicillium, and Mucor. There fungal species belonging to the genus identified in this study, can trigger serious diseases museum workers, such as for example Aspergillus fumigatus, known allergies and toxic effects that may occur. In some places of the museum, occupational exposure limit values to fungi present in the air in the work environment, recommended by the specialized literature, have been overcome.

  3. Magnetic properties changes due to hydrocarbon contaminated groundwater table fluctuations

    Science.gov (United States)

    Ameen, Nawrass

    2013-04-01

    This study aims to understand the mechanisms and conditions which control the formation and transformation of ferro(i)magnetic minerals caused by hydrocarbon contaminated groundwater, in particular in the zone of fluctuating water levels. The work extends previous studies conducted at the same site. The study area is a former military air base at Hradčany, Czech Republic (50°37'22.71"N, 14°45'2.24"E). The site was heavily contaminated with petroleum hydrocarbons, due to leaks in petroleum storage tanks and jet fuelling stations over years of active use by the Soviet Union, which closed the base in 1991. The site is one of the most important sources of high quality groundwater in the Czech Republic. In a previous study, Rijal et al. (2010) concluded that the contaminants could be flushed into the sediments as the water level rose due to remediation processes leading to new formation of magnetite. In this previous study three different locations were investigated; however, from each location only one core was obtained. In order to recognize significant magnetic signatures versus depth three cores from each of these three locations were drilled in early 2012, penetrating the unsaturated zone, the groundwater fluctuation (GWF) zone and extending to about one meter below the groundwater level (~2.3 m depth at the time of sampling). Magnetic susceptibility (MS) profiles combined with other magnetic properties were analyzed to obtain a significant depth distribution of the ferro(i)magnetic concentration. Sediment properties, hydrocarbon content and bacterial activity were additionally studied. The results show that the highest ferrimagnetic mineral concentrations exist between 1.4-1.9 m depth from the baseline which is interpreted as the top of the GWF zone. Spikes of MS detected in the previous studies turned out to represent small-scale isolated features, but the trend of increasing MS values from the lowermost position of the groundwater table upward was verified

  4. Fungi as contaminants in indoor air

    Science.gov (United States)

    Miller, J. David

    This article reviews the subject of contamination of indoor air with fungal spores. In the last few years there have been advances in several areas of research on this subject. A number of epidemiological studies have been conducted in the U.K., U.S.A. and Canada. These suggest that exposure to dampness and mold in homes is a significant risk factor for a number of respiratory symptoms. Well-known illnesses caused by fungi include allergy and hypersensitivity pneumonitis. There is now evidence that other consequences of exposure to spores of some fungi may be important. In particular, exposure to low molecular weight compounds retained in spores of some molds such as mycotoxins and β 1,3 glucans appears to contribute to some symptoms reported. Fungal contamination of building air is almost always caused by poor design and/or maintenance. Home owners and building operators need to take evidence of fungal contamination seriously.

  5. Air cleaning issues with contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    Bellamy, R.R. [Nuclear Regulatory Commission, King of Prussia, PA (United States)

    1997-08-01

    The US Nuclear Regulatory Commission has developed a list of contaminated sites that warrant special USNRC attention because they pose unique or complex decommissioning issues. This list of radiologically contaminated sites is termed the Site Decommissioning Management Plan (SDMP), and was first issued in 1990. A site is placed on the SDMP list if it has; (1) Problems with the viability of the responsible organization (e.g., the licensee for the site is unable or unwilling to pay for the decommissioning); (2) Large amounts of soil contamination or unused settling ponds or burial grounds that may make the waste difficult to dispose of; (3) The long-term presence of contaminated, unused buildings; (4) A previously terminated license; or (5) Contaminated or potential contamination of the ground water from on-site wastes. In deciding whether to add a site to the SDMP list, the NRC also considers the projected length of time for decommissioning and the willingness of the responsible organization to complete the decommissioning in a timely manner. Since the list was established, 9 sites have been removed from the list, and the current SDMP list contains 47 sites in 11 states. The USNRC annually publishes NUREG-1444, {open_quotes}Site Decommissioning Management Plan{close_quotes}, which updates the status of each site. This paper will discuss the philosophical goals of the SDMP, then will concentrate on the regulatory requirements associated with air cleaning issues at the SDMP sites during characterization and remediation. Both effluent and worker protection issues will be discussed. For effluents, the source terms at sites will be characterized, and measurement techniques will be presented. Off-site dose impacts will be included. For worker protection issues, air sampling analyses will be presented in order to show how the workers are adequately protected and their doses measured to satisfy regulatory criteria during decontamination operations. 1 tab.

  6. Space shuttle contamination due to backflow from control motor exhaust

    Science.gov (United States)

    Robertson, S. J.; Chan, S. T. K.; Lee, A. L.

    1976-01-01

    Spacecraft contamination of the space shuttle orbiter and accompanying Spacelab payloads is studied. The scattering of molecules from the vernier engines and flash evaporator nozzle after impingement on the orbiter wing surfaces, and the backflow of molecules out of the flash evaporator nozzle plume flow field due to intermolecular collisions in the plume are the problems discussed. A method was formulated for dealing with these problems, and detailed results are given.

  7. Wash-out of ambient air contaminations for breath measurements.

    Science.gov (United States)

    Maurer, F; Wolf, A; Fink, T; Rittershofer, B; Heim, N; Volk, T; Baumbach, J I; Kreuer, S

    2014-06-01

    In breath analysis, ambient air contaminations are ubiquitous and difficult to eliminate. This study was designed to investigate the reduction of ambient air background by a lung wash-out with synthetic air. The reduction of the initial ambient air volatile organic compound (VOC) intensity was investigated in the breath of 20 volunteers inhaling synthetic air via a sealed full face mask in comparison to inhaling ambient air. Over a period of 30 minutes, breath analysis was conducted using ion mobility spectrometry coupled to a multi-capillary column. A total of 68 VOCs were identified for inhaling ambient air or inhaling synthetic air. By treatment with synthetic air, 39 VOCs decreased in intensity, whereas 29 increased in comparison to inhaling ambient air. In total, seven VOCs were significantly reduced (P-value ambient air contaminations from the airways by a lung wash-out with synthetic air.

  8. LCD brightness decay due to particulate contamination of back light unit

    Science.gov (United States)

    Kim, Sanghoon; Lee, Sang-Chul; Yook, Se-Jin; Choi, Jung-Uk; Ahn, Kang-Ho

    2013-01-01

    So far, particulate contamination problems occurring in cleanroom environments have been intensively investigated by considering the product yield in semiconductor manufacturing or liquid crystal display (LCD) manufacturing. This study, however, focused on the particulate contamination problem causing the degradation of LCD TVs run in common environments. A field test was conducted by running a LCD TV in an office room for 60 days in order to collect and analyze the particles contaminating the backlight unit (BLU) of the LCD TV. Based on the field test result, soot particles were generated to simulate the contaminant particles, and an accelerated test was performed by exposing the LCD TV to a soot aerosol of relatively high concentration. As the exposure time was increased, the degree of particulate contamination of the BLU became more severe, and the decay rate of the LCD brightness increased. As a result, the particulate contamination of the BLU was found to greatly affect the decay rate of the LCD brightness. A numerical simulation was performed to elucidate the mechanism of particle influx into the BLU and to predict the particle deposition pattern. The contaminant particles could enter into the BLU through the gaps on the BLU casing due to the air flow induced by natural convection in the BLU. The particles were thought to have been deposited on the walls in the BLU, especially at the corner regions.

  9. 40 CFR 52.1988 - Air contaminant discharge permits.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Air contaminant discharge permits. 52.1988 Section 52.1988 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Oregon § 52.1988 Air...

  10. Contamination of Ground Water Due To Landfill Leachate

    Directory of Open Access Journals (Sweden)

    M. V. S. Raju

    2012-12-01

    Full Text Available The present site under investigation at Ajitsingh Nagar in Vijayawada of Andhra Pradesh is initially a low lying area and used for disposing the urban solid waste for the last few years, through open dumping with out taking any measures to protect the Ground water against pollution. The present study has been taken up to measure the degree of pollution of ground water due to leachate produced in the landfill site. Bore holes were made at eight random locations to measure the depth and characteristics of solid waste. Four sampling wells were made for the collection of ground water samples and they were analyzed for various parameters. All parameters were measured based on Standard methods. It is found that the ground water is contaminated due leachates of Landfill to the large extent and is not suitable for Drinking, Domestic and Irrigation purposes.

  11. Air pollution due to road traffic in Ljubljana

    OpenAIRE

    Matej Ogrin

    2007-01-01

    Air pollution is due to road traffic an inevitable outcome of internal combustion in engines of vehicles and some other processes. Air near the roads is more polluted with some pollutants, such as carbon monoxide, nitrogen oxides, ozone, particulate matter and some others. Monitoring the air quality is a key issue, when one wants to estimate environmental impacts of the road traffic. The article shows a method of passive samplers for air quality monitoring along different roads in the area of...

  12. Micro GC's for Contaminant Monitoring in Spacecraft Air Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposal is to create new gas chromatographs (GCs) for contaminant monitoring in spacecraft air that do not require any reagents or special...

  13. Trace Contaminant Monitor for Air in Spacecraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A need exists for analyzers that can measure trace contaminants in air on board spacecraft. Toxic gas buildup can endanger the crew particularly during long...

  14. Heavy Metal Contamination of Soil Due to Road Traffic

    Directory of Open Access Journals (Sweden)

    A. Athanasopoulou

    2017-01-01

    Full Text Available Particles coming from the pavement’s maintenance or from the traffic on it enter the soil carried by water. More pollutants transferred by air are dispersed in different distances, also polluting the soil. Precautionary and remedial measures are suggested for urban, peri-urban, and rural zones crossed by roadways, as a function of the plants' species and the level of the road. The proposed measures are based on the soil's chemical composition and draining conditions. Iron and the non-volatile heavy metals, copper, zinc, cadmium, lead, chromium, nickel, are often found in roadside topsoil, as well as in roots and leafage of vegetables and trees. Manganese is found in combination with iron in many minerals and not as free element. The reasons and frequency of existence of metals have to be examined so as to take measures against contamination and possible health hazards. Heavy metal concentrations of soils have been seldom studied in Greece and there is a lack of data sources for the environmental impact of these elements in soil and dust from the pavements and the traffic. The impacts of road construction and service on the surrounding soil masses are studied and analyzed in view of their quality as nutrient materials

  15. Modeling, Monitoring and Fault Diagnosis of Spacecraft Air Contaminants

    Science.gov (United States)

    Ramirez, W. Fred; Skliar, Mikhail; Narayan, Anand; Morgenthaler, George W.; Smith, Gerald J.

    1998-01-01

    Control of air contaminants is a crucial factor in the safety considerations of crewed space flight. Indoor air quality needs to be closely monitored during long range missions such as a Mars mission, and also on large complex space structures such as the International Space Station. This work mainly pertains to the detection and simulation of air contaminants in the space station, though much of the work is easily extended to buildings, and issues of ventilation systems. Here we propose a method with which to track the presence of contaminants using an accurate physical model, and also develop a robust procedure that would raise alarms when certain tolerance levels are exceeded. A part of this research concerns the modeling of air flow inside a spacecraft, and the consequent dispersal pattern of contaminants. Our objective is to also monitor the contaminants on-line, so we develop a state estimation procedure that makes use of the measurements from a sensor system and determines an optimal estimate of the contamination in the system as a function of time and space. The real-time optimal estimates in turn are used to detect faults in the system and also offer diagnoses as to their sources. This work is concerned with the monitoring of air contaminants aboard future generation spacecraft and seeks to satisfy NASA's requirements as outlined in their Strategic Plan document (Technology Development Requirements, 1996).

  16. Cadmium Release in Contaminated Soils due to Organic Acids

    Institute of Scientific and Technical Information of China (English)

    LIAO Min; XIE Xiao-Mei

    2004-01-01

    There is limited information on the release behavior of heavy metals from natural soils by organic acids. Thus,cadmium release,due to two organic acids (tartrate and citrate) that are common in the rhizosphere,from soils polluted by metal smelters or tailings and soils artificially contaminated by adding Cd were analyzed. The presence of tartrate or citrate at a low concentration (≤6mmol L-1 for tartrate and ≤0.5 mmol L-1 for citrate) inhibited Cd release,whereas the presence of organic acids in high concentrations (≥2 mmol L-1 for citrate and ≥15 mmol L-1 for tartrate)apparently promoted Cd release. Under the same conditions,the Cd release in naturally polluted soils was less than that of artificially contaminated soils. Additionally,as the initial pH rose from 2 to 8 in the presence of citrate,a sequential valley and then peak appeared in the Cd release curve,while in the presence of tartrate the Cd release steadily decreased.In addition,Cd release was clearly enhanced as the electrolyte concentration of KNO3 or KC1 increased in the presence of 2 mmol L-1 tartrate. Moreover,a higher desorption of Cd was shown with the KC1 electrolyte compared to KNO3 for the same concentration levels. This implied that the bioavailability of heavy metals could be promoted with the addition of suitable types and concentrations of organic acids as well as reasonable field conditions.

  17. Air pollution due to road traffic in Ljubljana

    Directory of Open Access Journals (Sweden)

    Matej Ogrin

    2007-01-01

    Full Text Available Air pollution is due to road traffic an inevitable outcome of internal combustion in engines ofvehicles and some other processes. Air near the roads is more polluted with some pollutants,such as carbon monoxide, nitrogen oxides, ozone, particulate matter and some others.Monitoring the air quality is a key issue, when one wants to estimate environmental impactsof the road traffic. The article shows a method of passive samplers for air quality monitoringalong different roads in the area of Ljubljana Municipality.

  18. U. S. Air Force approach to plume contamination

    Science.gov (United States)

    Furstenau, Ronald P.; McCay, T. Dwayne; Mann, David M.

    1980-08-01

    Exhaust products from rocket engine firings can produce undesirable effects on sensitive satellite surfaces, such as optical systems, solar cells, and thermal control surfaces. The Air Force has an objective of minimizing the effect of rocket plume contamination on space-craft mission effectiveness. Plume contamination can result from solid rocket motors, liquid propellant engines, and electric thrusters. To solve the plume contamination problem, the Air Force Rocket Propulsion Laboratory (AFRPL) has developed a plume contamination computer model which predicts the production, transport, and deposition of rocket exhaust products. In addition, an experimental data base is being obtained through ground-based vacuum chamber experiments and in-flight measurements with which to compare the analytical results. Finally, the experimental data is being used to verify and improve the analytical model. The plume contamination model, known as CONTAM, has been used to make contamination predictions for various engines. The experimental programs have yielded quantitative data, such as species concentrations and temperatures, in all regions of the plume. The result of the modelling and experimental programs will ultimately be computer models which can be used by the satellite designer to analyze and to minimize the effect plume contamination will have on a particular spacecraft system.

  19. Bacillus cereus bacteremia outbreak due to contaminated hospital linens.

    Science.gov (United States)

    Sasahara, T; Hayashi, S; Morisawa, Y; Sakihama, T; Yoshimura, A; Hirai, Y

    2011-02-01

    We describe an outbreak of Bacillus cereus bacteremia that occurred at Jichi Medical University Hospital in 2006. This study aimed to identify the source of this outbreak and to implement appropriate control measures. We reviewed the charts of patients with blood cultures positive for B. cereus, and investigated B. cereus contamination within the hospital environment. Genetic relationships among B. cereus isolates were analyzed. Eleven patients developed B. cereus bacteremia between January and August 2006. The hospital linens and the washing machine were highly contaminated with B. cereus, which was also isolated from the intravenous fluid. All of the contaminated linens were autoclaved, the washing machine was cleaned with a detergent, and hand hygiene was promoted among the hospital staff. The number of patients per month that developed new B. cereus bacteremia rapidly decreased after implementing these measures. The source of this outbreak was B. cereus contamination of hospital linens, and B. cereus was transmitted from the linens to patients via catheter infection. Our findings demonstrated that bacterial contamination of hospital linens can cause nosocomial bacteremia. Thus, blood cultures that are positive for B. cereus should not be regarded as false positives in the clinical setting.

  20. Uncertainties Associated with Flux Measurements Due to Heterogeneous Contaminant Distributions

    Science.gov (United States)

    Mass flux and mass discharge measurements at contaminated sites have been applied to assist with remedial management, and can be divided into two broad categories: point-scale measurement techniques and pumping methods. Extrapolation across un-sampled space is necessary when usi...

  1. Anthropogenic heating of the urban environment due to air conditioning

    Science.gov (United States)

    Salamanca, F.; Georgescu, M.; Mahalov, A.; Moustaoui, M.; Wang, M.

    2014-05-01

    This article investigates the effect of air conditioning (AC) systems on air temperature and examines their electricity consumption for a semiarid urban environment. We simulate a 10 day extreme heat period over the Phoenix metropolitan area (U.S.) with the Weather Research and Forecasting model coupled to a multilayer building energy scheme. The performance of the modeling system is evaluated against 10 Arizona Meteorological Network weather stations and one weather station maintained by the National Weather Service for air temperature, wind speed, and wind direction. We show that explicit representation of waste heat from air conditioning systems improved the 2 m air temperature correspondence to observations. Waste heat release from AC systems was maximum during the day, but the mean effect was negligible near the surface. However, during the night, heat emitted from AC systems increased the mean 2 m air temperature by more than 1°C for some urban locations. The AC systems modified the thermal stratification of the urban boundary layer, promoting vertical mixing during nighttime hours. The anthropogenic processes examined here (i.e., explicit representation of urban energy consumption processes due to AC systems) require incorporation in future meteorological and climate investigations to improve weather and climate predictability. Our results demonstrate that releasing waste heat into the ambient environment exacerbates the nocturnal urban heat island and increases cooling demands.

  2. Circumventing shallow air contamination in Mid Ocean Ridge Basalts

    Science.gov (United States)

    Mukhopadhyay, Sujoy; Parai, Rita; Tucker, Jonathan; Middleton, Jennifer; Langmuir, Charles

    2016-04-01

    Noble gases in mantle-derived basalts provide a rich portrait of mantle degassing and surface-interior volatile exchange. However, the ubiquity of shallow-level air contamination frequently obscures the mantle noble gas signal. In a majority of samples, shallow air contamination dominates the noble gas budget. As a result, reconstructing the variability in heavy noble gas mantle source compositions and inferring the history of deep recycling of atmospheric noble gases is difficult. For example, in the gas-rich popping rock 2ΠD43, 129Xe/130Xe ratios reach 7.7±0.23 in individual step-crushes, but the bulk composition of the sample is close to air (129Xe/130Xe of 6.7). Here, we present results from experiments designed to elucidate the source of shallow air contamination in MORBs. Step-crushes were carried out to measure He, Ne, Ar and Xe isotopic compositions on two aliquots of a depleted popping glass that was dredged from between the Kane and Atlantis Fracture Zones of the Mid-Atlantic Ridge in May 2012. One aliquot was sealed in ultrapure N2 after dredge retrieval, while the other aliquot was left exposed to air for 3.5 years. The bulk 20Ne/22Ne and 129Xe/130Xe ratios measured in the aliquot bottled in ultrapure N2 are 12.3 and 7.6, respectively, and are nearly identical to the estimated mantle source values. On the other hand, step crushes in the aliquot left exposed to air for several years show Ne isotopic compositions that are shifted towards air, with a bulk 20Ne/22Ne of 11.5; the bulk 129Xe/130Xe, however, was close to 7.6. These results indicate that lighter noble gases exchange more efficiently between the bubbles trapped in basalt glass and air, suggesting a diffusive or kinetic mechanism for the incorporation of the shallow air contamination. Importantly, in Ne-Ar or Ar-Xe space, step-crushes from the bottled aliquot display a trend that can be easily fit with a simple two-component hyperbolic mixing between mantle and atmosphere noble gases. Step

  3. Concentrations of selected contaminants in cabin air of airbus aircrafts.

    Science.gov (United States)

    Dechow, M; Sohn, H; Steinhanses, J

    1997-07-01

    The concentrations of selected air quality parameters in aircraft cabins were investigated including particle numbers in cabin air compared to fresh air and recirculation air, the microbiological contamination and the concentration of volatile organic compounds (VOC). The Airbus types A310 of Swissair and A340 of Lufthansa were used for measurements. The particles were found to be mainly emitted by the passengers, especially by smokers. Depending on recirculation filter efficiency the recirculation air contained a lower or equal amount of particles compared to the fresh air, whereas the amount of bacteria exceeded reported concentrations within other indoor spaces. The detected species were mainly non-pathogenic, with droplet infection over short distances identified as the only health risk. The concentration of volatile organic compounds (VOC) were well below threshold values. Ethanol was identified as the compound with the highest amount in cabin air. Further organics were emitted by the passengers--as metabolic products or by smoking--and on ground as engine exhaust (bad airport air quality). Cleaning agents may be the source of further compounds.

  4. Outbreak of methylmercury poisoning due to consumption of contaminated grain

    Energy Technology Data Exchange (ETDEWEB)

    Clarkson, T.W.; Amin-Zaki, L.; Al-Tikriti, S.K.

    1976-10-01

    An outbreak of methylmercury poisoning took place in the fall and winter of 1971 to 1972 in Iraq. Six thousand five hundred and thirty cases were admitted to hospitals throughout the country and 459 died in hospital. The outbreak was the result of eating homemade bread prepared from wheat treated with a methylmercury fungicide. The wheat was intended for planting purposes only. Signs and symptoms of poisonings in adults indicate that the major site of action of this form of mercury is the central nervous system. Severe brain damage also resulted from prenatal exposure when the mother ingested large amounts of the contaminated bread. The frequency of signs and symptoms in an exposed population was found to be related to the estimated maximum blood levels, i.e., the concentration in blood at the end of exposure. A small percentage of the population exhibited a significant increase in complaints of paresthesia at maximum blood levels in the range of 240 to 480 ng Hg/ml. At higher blood levels a greater proportion of the population complained of paresthesia and other signs and symptoms became apparent.

  5. Biofiltration of air contaminated with methanol and toluene

    Directory of Open Access Journals (Sweden)

    Pakamas Chetpattananondh

    2005-12-01

    Full Text Available Biofiltration of air contaminated with VOCs is inexpensive compared with the conventional techniques and very effective for treating large volumes of moist air streams with low concentrations of VOCs. In this study, biofiltration for the purification of polluted air from methanol, a hydrophilic VOC, and toluene, a hydrophobic VOC, was investigated. The experiments were operated using three separated stainless steel biofilters, for methanol, toluene, and a mixture of methanol and toluene, respectively. Biofilter consisted of a mixture of palm shells and activated sludge as a filter-bed material. Only the indigenous microorganisms of the bed medium without any addition of extra inoculum were used throughout the whole process. The polluted air inlet concentration was varied from 0.3-4.7 g/m3 with flow rates ranging from 0.06-0.45 m3/h, equivalent to the empty bed residence times of 9-71 sec. Polluted air was successfully treated by biofiltration, 100% removal efficiencies would be obtained when the air flow rate was lower than 0.45 m3/h. The presence of toluene did not affect the removal rate of methanol while the removal rate of toluene was decreased with the presence of methanol in air stream according to the competition phenomenon.

  6. Recommended Concentration Limits of Typical Indoor Air Contaminants

    Institute of Scientific and Technical Information of China (English)

    LV Chao; JIANG Yun-tao; ZHAO Jia-ning

    2009-01-01

    From the view of both objective and subjective factors.the indoor air quality(IAQ)evaluation was considered.Carbon dioxide (CO2) and formaldehyde (HCHO) were selected as the typical contaminants of indoor air,and the evaluation method of logarithmic index was adopted as the evaluation means of IAQ.Then the recommended limits (RL) of typical contaminants CO2 and HCHO were given through analysis and calcula-tion.The limits of CO2 and HCHO in Indoor Air Quahty Standard of China or other existing standards probably correspond to the level of PD=25(%).The result shows that the existing standards fail to meet the require-ment of the definition of"acceptable indoor air quality",that is to say,less than 20% of the people express dis-satisfaction.When PD=20%,RL of CO2 and HCHO are 728×10-6 and 0.068×10-6 respectively,which are stricter than the limits in the existing standards.The method proposed in this paper is applicable to 13.1%≤PD≤86.7%.

  7. Air pollution effects due to deregulation of the electric industry

    Science.gov (United States)

    Davoodi, Khojasteh Riaz

    ) nuclear sources until the year 2005. Each module was analyzed separately and the result from each module was transferred into the Air Quality Impact model. The model assesses the changes in electricity generation within each module due to deregulation and these changes can then be correlated to the emission of air pollutants in the United States.

  8. Methodology for modeling the microbial contamination of air filters.

    Directory of Open Access Journals (Sweden)

    Yun Haeng Joe

    Full Text Available In this paper, we propose a theoretical model to simulate microbial growth on contaminated air filters and entrainment of bioaerosols from the filters to an indoor environment. Air filter filtration and antimicrobial efficiencies, and effects of dust particles on these efficiencies, were evaluated. The number of bioaerosols downstream of the filter could be characterized according to three phases: initial, transitional, and stationary. In the initial phase, the number was determined by filtration efficiency, the concentration of dust particles entering the filter, and the flow rate. During the transitional phase, the number of bioaerosols gradually increased up to the stationary phase, at which point no further increase was observed. The antimicrobial efficiency and flow rate were the dominant parameters affecting the number of bioaerosols downstream of the filter in the transitional and stationary phase, respectively. It was found that the nutrient fraction of dust particles entering the filter caused a significant change in the number of bioaerosols in both the transitional and stationary phases. The proposed model would be a solution for predicting the air filter life cycle in terms of microbiological activity by simulating the microbial contamination of the filter.

  9. contamination nucléaire par laser UV

    Science.gov (United States)

    Delaporte, Ph.; Gastaud, M.; Marine, W.; Sentis, M.; Uteza, O.; Thouvenot, P.; Alcaraz, J. L.; Le Samedy, J. M.; Blin, D.

    2003-06-01

    Le développement et l'utilisation de procédés propres pour le nettoyage ou la préparation de surfaces est l'une des priorités du milieu industriel. Cet intérêt est d'autant plus grand dans le domaine du nucléaire pour lequel la réduction des déchets est un axe de recherche important. Un dispositif de décontamination nucléaire par laser UV impulsionnel a été développé et testé. Il est composé. d'un laser à excimères de 1kW, d'un faisceau de fibres optiques et d'un dispositif de récupération des particules. Les essais réalisés en milieu actif ont démontré sa capacité à nettoyer des surfaces métalliques polluées par différents radioéléments avec des facteurs de décontamination généralement supérieurs à 10. Ce dispositif permet de décontaminer de grandes surfaces de géométrie simple en réduisant fortement la génération de déchets secondaires. Il est, à ce jour et dans ces conditions d'utilisations, le procédé de décontamination par voie sèche le plus efficace.

  10. Characterization of the frequency and nature of bleed air contamination events in commercial aircraft.

    Science.gov (United States)

    Shehadi, M; Jones, B; Hosni, M

    2016-06-01

    Contamination of the bleed air used to pressurize and ventilate aircraft cabins is of concern due to the potential health and safety hazards for passengers and crew. Databases from the Federal Aviation Administration, NASA, and other sources were examined in detail to determine the frequency of bleed air contamination incidents. The frequency was examined on an aircraft model basis with the intent of identifying aircraft make and models with elevated frequencies of contamination events. The reported results herein may help investigators to focus future studies of bleed air contamination incidents on smaller number of aircrafts. Incident frequency was normalized by the number of aircraft, number of flights, and flight hours for each model to account for the large variations in the number of aircraft of different models. The focus of the study was on aircraft models that are currently in service and are used by major airlines in the United States. Incidents examined in this study include those related to smoke, oil odors, fumes, and any symptom that might be related to exposure to such contamination, reported by crew members, between 2007 and 2012, for US-based carriers for domestic flights and all international flights that either originated or terminated in the US. In addition to the reported frequency of incidents for different aircraft models, the analysis attempted to identify propulsion engines and auxiliary power units associated with aircrafts that had higher frequencies of incidents. While substantial variations were found in frequency of incidents, it was found that the contamination events were widely distributed across nearly all common models of aircraft.

  11. Modeling of Air Temperature for Heat Exchange due to Vertical Turbulence and Horizontal Air Flow

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lei; MENG Qing-lin

    2009-01-01

    In order to calculate the air temperature of the near surface layer in urban environment,the Sur-face layer air was divided into several layers in the vertical direction,and some energy bakmce equations were de-veloped for each air layer,in which the heat exchange due to vertical turbulence and horizontal air flow was tak-en into account.Then,the vertical temperature distribution of the surface layer air was obtained through the coupled calculation using the energy balance equations of underlying surfaces and building walls.Moreover,the measured air temperatures in a small area (with a horizontal scale of less than 500 m) and a large area (with ahorizontal scale of more than 1000 m) in Guangzhou in summer were used to validate the proposed model.The calculated results agree well with the measured ones,with a maximum relative error of 4.18%.It is thus con-cluded that the proposed model is a high-accuracy method to theoretically analyze the urban heat island and the thermal environment.

  12. Technological, economic, and political feasibility in OSHA's Air Contaminants Standard

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, J.C.; Paxman, D.G. (Univ. of California, Berkeley (USA))

    In 1989, after almost two decades of substance-by-substance standard setting, the Occupational Safety and Health Administration (OSHA) promulgated its Air Contaminants Standard, imposing new exposure limits for 376 toxic substances encountered in U.S. industry. In marked contrast to earlier regulations, the Air Contaminants Standard has generated relatively little industry opposition. This paper analyzes the standard in the context of the twenty-year debate over the appropriate role for technological feasibility and economic compliance costs in occupational health policy. The political feasibility of the new standard is traced to OSHA's abandonment of technology forcing in favor of reliance on off-the-shelf technologies already in use in major firms. While important as an embodiment of OSHA's new generic approach to regulation, the Air Contaminants Standard cannot serve as a model for future occupational health policy, due to its reliance on informal, closed-door mechanisms for establishing regulatory priorities and permissible exposure limits. 20 refs.

  13. The contaminant removal efficiency of an air cleaner using the adsorption/desorption effect

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Hiroshi [Toyohashi University of Technology, 1-1 Hibariga-oka, Tempakucho, Toyohashi 441-8580 (Japan); Shimizu, Masayuki [Sala Housing Corporation, Toyohashi 441-8021 (Japan); Sato, Hiroyasu [TOENEC Corporation, Nagoya 460-0008 (Japan)

    2009-07-15

    The adsorption and desorption of volatile organic compounds (VOCs) in relation to material surfaces were conducted to control indoor air quality. The VOC removal performance of building materials using sorption effects was validated in cases related to poor indoor air quality that occurred during non-ventilation periods during intermittent-ventilation situations. The objective of this investigation is to present the contaminant removal efficiency and practicality of a prototype air cleaner which uses sorption effects. Toluene and formaldehyde were used as pollutant sources and were continuously emitted into the test chamber. Effects due to the number of sorption units, operation time and mode of contaminant removal performance were examined. The sorption materials evaluated in this investigation were a porous material, zeolite, pumice stone and hydro-corn. As a result of the experiments, zeolite exhibited relatively high contaminant removal efficiency with toluene, and zeolite and the porous material exhibited high removal efficiency with formaldehyde for both one-cycle and two-cycle sorption modes. Moreover, significant removal performances were observed in the numerical analysis of the continuous-operation mode. (author)

  14. Black-footed albatross contamination due to global and local contamination

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This study was initiated due to the high levels of PCBs (2300 ppm in soil, 660ppb in sediment, 40ppb groundwater) and lead (2800 ppm soil) found on Tern Island in...

  15. Wire-Mesh-Based Sorber for Removing Contaminants from Air

    Science.gov (United States)

    Perry, Jay; Roychoudhury, Subir; Walsh, Dennis

    2006-01-01

    A paper discusses an experimental regenerable sorber for removing CO2 and trace components principally, volatile organic compounds, halocarbons, and NH3 from spacecraft cabin air. This regenerable sorber is a prototype of what is intended to be a lightweight alternative to activated-carbon and zeolite-pellet sorbent beds now in use. The regenerable sorber consists mainly of an assembly of commercially available meshes that have been coated with a specially-formulated washcoat containing zeolites. The zeolites act as the sorbents while the meshes support the zeolite-containing washcoat in a configuration that affords highly effective surface area for exposing the sorbents to flowing air. The meshes also define flow paths characterized by short channel lengths to prevent excessive buildup of flow boundary layers. Flow boundary layer resistance is undesired because it can impede mass and heat transfer. The total weight and volume comparison versus the atmosphere revitalization equipment used onboard the International Space Station for CO2 and trace-component removal will depend upon the design details of the final embodiment. However, the integrated mesh-based CO2 and trace-contaminant removal system is expected to provide overall weight and volume savings by eliminating most of the trace-contaminant control equipment presently used in parallel processing schemes traditionally used for spacecraft. The mesh-based sorbent media enables integrating the two processes within a compact package. For the purpose of regeneration, the sorber can be heated by passing electric currents through the metallic meshes combined with exposure to space vacuum. The minimal thermal mass of the meshes offers the potential for reduced regeneration-power requirements and cycle time required for regeneration compared to regenerable sorption processes now in use.

  16. [Outbreak due to Serratia marcescens associated with intrinsic contamination of aqueous chlorhexidine].

    Science.gov (United States)

    Hervé, Beatrice; Chomali, May; Gutiérrez, Cecilia; Luna, Mariana; Rivas, Jeannette; Blamey, Rodrigo; Espinoza, Ricardo; Izquierdo, Giannina; Cabezas, Catalina; Alvarez, Claudia; de la Fuente, Sebastián

    2015-10-01

    Serratia marcescens is a widely distributed gram-negative rod, often associated to nosocomial infections. Some outbreaks linked to contaminated antiseptic solutions have been reported. In this study we report a nosocomial outbreak of surgical site infection and catheter insertion site infection due to S. marcescens. 33 patients with positive cultures were studied after an index case was identified. Epidemiological, microbiological and molecular analysis demostrated an intrinsic contamination of alcohol free chlorhexidine solution as causal factor. Positive cultures were associated with 13 clinical infections, 9 colonized patients, 6 pseudobacteremia episodes and 5 patients without documented exposure. Hospital and national recall of contaminated chlorhexidine solution was performed after this study. Intrinsic contamination of antiseptic solutions is an infrequent cause of nosocomial infections with major epidemiological relevance.

  17. Tolerance of non-platinum group metals cathodes proton exchange membrane fuel cells to air contaminants

    Science.gov (United States)

    Reshetenko, Tatyana; Serov, Alexey; Artyushkova, Kateryna; Matanovic, Ivana; Sarah Stariha; Atanassov, Plamen

    2016-08-01

    The effects of major airborne contaminants (SO2, NO2 and CO) on the spatial performance of Fe/N/C cathode membrane electrode assemblies were studied using a segmented cell system. The injection of 2-10 ppm SO2 in air stream did not cause any performance decrease and redistribution of local currents due to the lack of stably adsorbed SO2 molecules on Fe-Nx sites, as confirmed by density functional theory (DFT) calculations. The introduction of 5-20 ppm of CO into the air stream also did not affect fuel cell performance. The exposure of Fe/N/C cathodes to 2 and 10 ppm NO2 resulted in performance losses of 30 and 70-75 mV, respectively. DFT results showed that the adsorption energies of NO2 and NO were greater than that of O2, which accounted for the observed voltage decrease and slight current redistribution. The cell performance partially recovered when the NO2 injection was stopped. The long-term operation of the fuel cells resulted in cell performance degradation. XPS analyses of Fe/N/C electrodes revealed that the performance decrease was due to catalyst degradation and ionomer oxidation. The latter was accelerated in the presence of air contaminants. The details of the spatial performance and electrochemical impedance spectroscopy results are presented and discussed.

  18. Application of air ions for bacterial de-colonization in air filters contaminated by aerosolized bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yang Seon, E-mail: rup2r@yonsei.ac.kr [School of Mechanical Engineering, Yonsei University, 262 Seongsanno, Seodaemun-Gu, Seoul, 120-749 (Korea, Republic of); Yoon, Ki Young, E-mail: yky810921@yonsei.ac.kr [Exhaust Emission Engineering Team, Hyundai Motor Company, Hwaseong 445-706, Republic of Korea (Korea, Republic of); Park, Jae Hong, E-mail: cheap@yonsei.ac.kr [School of Mechanical Engineering, Yonsei University, 262 Seongsanno, Seodaemun-Gu, Seoul, 120-749 (Korea, Republic of); Hwang, Jungho, E-mail: hwangjh@yonsei.ac.kr [School of Mechanical Engineering, Yonsei University, 262 Seongsanno, Seodaemun-Gu, Seoul, 120-749 (Korea, Republic of)

    2011-01-15

    We aerosolized the Escherichia coli (E. coli) and Staphylococcus epidermidis (S. epidermidis) bacteria and collected them on membrane filters. Then we generated air ions by applying a high voltage to a carbon fiber tip and applied them to the contaminated filters. The antibacterial efficiency was not significantly affected by the bacteria being Gram-positive or Gram-negative, however, negative ions showed a lower antibacterial efficiency than positive ions to both E. coli and S. epidermidis, even though the concentration of negative air ions was much higher than that of positive air ions. With a field emission scanning electron microscope (FE-SEM) images and fluorescence microscopy images using a LIVE/DEAD BacLight Bacterial Viability Kit, electrostatic disruption of the bacteria was found to be the dominant antibacterial effect. - Research Highlights: {yields}This study examined the effects of air ions generated by a carbon fiber ionizer on the inactivation of bioaerosols. {yields}When the ion exposure time and the ion generation concentration were increased, the antibacterial efficiency increased. {yields}The bioaerosols carried a significant number of negative electrical charges. {yields}Negative ions showed lower antibacterial efficiency than positive ions to both E. coli and S. epidermidis, even though the concentration of negative air ions was much higher than that of positive air ions.

  19. Indoor air contamination during a waterpipe (narghile) smoking session.

    Science.gov (United States)

    Fromme, Hermann; Dietrich, Silvio; Heitmann, Dieter; Dressel, Holger; Diemer, Jürgen; Schulz, Thomas; Jörres, Rudolf A; Berlin, Knut; Völkel, Wolfgang

    2009-07-01

    The smoke of waterpipe contains numerous substances of health concern, but people mistakenly believe that this smoking method is less harmful and addictive than cigarettes. An experiment was performed in a 57 m3 room on two dates with no smoking on the first date and waterpipe smoking for 4h on the second date. We measured volatile organic compounds (VOC), polycyclic aromatic hydrocarbons (PAH), metals, carbon monoxide (CO), nitrogen oxides (e.g. NO), as well as particle mass (PM), particle number concentration (PNC) and particle surface area in indoor air. High concentrations were observed for the target analytes during the 4-h smoking event. The median (90th percentile) values of PM(2.5), PNC, CO and NO were 393 (737 microg/m(3)), 289,000 (550,000 particles/cm(3)), 51 (65 ppm) and 0.11 (0.13 ppm), respectively. The particle size distribution has a maximum of particles relating to a diameter of 17 nm. The seven carcinogenic PAH were found to be a factor 2.6 higher during the smoking session compared to the control day. In conclusion, the observed indoor air contamination of different harmful substances during a WP session is high, and exposure may pose a health risk for smokers but in particular for non-smokers who are exposed to ETS.

  20. Methods for Sampling and Measurement of Compressed Air Contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Stroem, L.

    1976-10-15

    In order to improve the technique for measuring oil and water entrained in a compressed air stream, a laboratory study has been made of some methods for sampling and measurement. For this purpose water or oil as artificial contaminants were injected in thin streams into a test loop, carrying dry compressed air. Sampling was performed in a vertical run, down-stream of the injection point. Wall attached liquid, coarse droplet flow, and fine droplet flow were sampled separately. The results were compared with two-phase flow theory and direct observation of liquid behaviour. In a study of sample transport through narrow tubes, it was observed that, below a certain liquid loading, the sample did not move, the liquid remaining stationary on the tubing wall. The basic analysis of the collected samples was made by gravimetric methods. Adsorption tubes were used with success to measure water vapour. A humidity meter with a sensor of the aluminium oxide type was found to be unreliable. Oil could be measured selectively by a flame ionization detector, the sample being pretreated in an evaporation- condensation unit

  1. Volatile tritiated organic acids in stack effluents and in air surrounding contaminated materials

    Energy Technology Data Exchange (ETDEWEB)

    Belot, Y.; Camus, H.; Marini, T.; Raviart, S. (Institut de Protection et de Surete Nucleaire (France))

    1993-06-01

    A small fraction of the tritium released into the atmosphere from tritium-handling or solid waste storage facilities was shown to be in the form of volatile organic acids. The same compounds were also found, but at a much higher proportion, in the tritium evolved at room temperature from highly contaminated materials placed under air atmospheres. This might be due to the oxidation and labeling of hydrocarbon(s) by mechanisms that are presumably of a radiolytic nature. The new forms could have an impact on operational requirements and waste management strategies within a tritium facility and a fusion reactor hall. Further data are needed to assess the related doses.

  2. Geoelectric assessment of soil properties modification due to underground water contamination

    Science.gov (United States)

    Chitea, F.; Ioane, D.; Georgescu, P.; Mezincescu, M.

    2009-04-01

    Geophysical investigations, including resistivity and conductivity measurements, have been carried out in an agricultural area with variations of crop growth, located in the vicinity of the Petrobrazi oil refinery, Romania. The scientific project was devoted to the geoelectric assessment of soil and underground water contamination with oil derived products, based on the physical properties modification due to high resistivity contaminants. The shallow geological structure consists of soil (1 m), loess (0.5 m), sandy gravels (20 m) and clay, the oil contaminants being displaced horizontally by the aquifer dynamics with ca 100 m/year at a mean depth of 5 m, at the limit between the vadose and saturated zones. Due to sudden increase of underground contaminantion during technical accidents within the refinery, when the contaminant height above the aquifer reached 4.5 m, and oscilations of water table level associated with seasonal high precipitation regime, the geological formations within the vadose zone were upward polluted. More of that, due to capillarity processes developed on more then 70 years of industrial activity, this upward contamination affected also the soil layer. Results of 3D multielectrode resistivity measurements using the AGI SuperSting showed significant variations of this physical parameter between the surface and 1 m depth. The southern sector, affected by high contamination at the aquifer depth displays high resistivity values, the highest geoelectric anomalies being interpreted as small areas where oil derived products accumulated as a consequence of vertical migration. The soil of the southern sector is characterised by low resistivity values, suggesting that upward contamination processes were much weaker. In the area surveyed with the multielectrode system, conductivity measurements were carried out using a high resolution conductivity meter. Variations of soil quality between the northern sector and the southern one have been observed also

  3. Biological air contamination in elderly care centers: geria project.

    Science.gov (United States)

    Aguiar, Lívia; Mendes, Ana; Pereira, Cristiana; Neves, Paula; Mendes, Diana; Teixeira, João Paulo

    2014-01-01

    Indoor air quality (IAQ) affects health particularly in susceptible individuals such as the elderly. It has been estimated that the older population spends approximately 19-20 h/d indoors, and the majority of the elderly spend all of their time indoors in elderly care centers (ECC). Older individuals may be particularly at risk of exposure to detrimental effects from pollutants, even at low concentrations, due to common and multiple underlying chronic diseases that increase susceptibility. This study, aimed to assess the impact of indoor biological agents in 22 ECC located in Porto, was conducted during summer and winter from November 2011 to August 2013 at a total of 141 areas within dining rooms, drawing rooms, medical offices, and bedrooms (including the bedridden). Air sampling was carried out with a microbiological air sampler (Merck MAS-100) and using tryptic soy agar for bacteria and malt extract agar for fungi. The results obtained were compared with the recently revised Portuguese standards. In winter, mean fungi concentration exceeded reference values, while bacteria concentrations were within the new standards in both seasons. The main fungi species found indoors were Cladosporium (73%) in summer and Penicillium (67%) in winter. Aspergillus fumigatus, Aspergillus niger, and Aspergillus flavus, known potential pathogenic/toxigenic species, were also identified. Although the overall rate and mean values of bacteria and fungi found in ECC indoor air met Portuguese legislation, some concern is raised by the presence of pathogenic microorganisms. Simple measures, like opening windows and doors to promote air exchange and renewal, may improve effectiveness in enhancing IAQ.

  4. Air pollution and health risks due to vehicle traffic

    OpenAIRE

    Zhang, Kai; Batterman, Stuart

    2013-01-01

    Traffic congestion increases vehicle emissions and degrades ambient air quality, and recent studies have shown excess morbidity and mortality for drivers, commuters and individuals living near major roadways. Presently, our understanding of the air pollution impacts from congestion on roads is very limited. This study demonstrates an approach to characterize risks of traffic for on- and near-road populations. Simulation modeling was used to estimate on- and near-road NO2 concentrations and he...

  5. Hot air injection for removal of dense, non-aqueous-phase liquid contaminants from low-permeability soils

    Energy Technology Data Exchange (ETDEWEB)

    Payne, F.C.

    1996-08-01

    The performance of soil vapor extraction systems for the recovery of volatile and semi-volatile organic compounds is potentially enhanced by the injection of heated air to increase soil temperatures. The soil temperature increase is expected to improve soil vapor extraction (SVE) performance by increasing target compound vapor pressures and by increasing soil permeability through drying. The vapor pressure increase due to temperature rise relieves the vapor pressure limit on the feasibility of soil vapor extraction. However, the system still requires an air flow through the soil system to deliver heat and to recover mobilized contaminants. Although the soil permeability can be increased through drying, very low permeability soils and low permeability soils adjacent to high permeability air flow pathways will be treated slowly, if at all. AR thermal enhancement methods face this limitation. Heated air injection offers advantages relative to other thermal techniques, including low capital and operation costs. Heated air injection is at a disadvantage relative to other thermal techniques due to the low heat capacity of air. To be effective, heated air injection requires that higher air flows be established than for steam injection or radio frequency heating. Heated air injection is not economically feasible for the stratified soil system developed as a standard test for this document. This is due to the inability to restrict heated air flow to the clay stratum when a low-resistance air flow pathway is available in the adjoining sand. However, the technology should be especially attractive, both technically and economically, for low-volatile contaminant recovery from relatively homogeneous soil formations. 16 refs., 2 tabs.

  6. Exposure Due to Interacting Air flows Between Two Persons

    DEFF Research Database (Denmark)

    Bjørn, Erik; Nielsen, Peter V.

    The contaminant concentration inhaled by an occupant (ie. the personal exposure) is usually less than the return concentration in displacement ventilated rooms. Two main questions are investigated: 1) Does the exhalation from one person penetrate the breathing zone of another person placed nearby......, thus leading to larger personal exposure? 2) When two persons are placed close to each other, do the convective boundary layer flows interact so that the personal exposure to an ambient concentration field is altered?...

  7. Nitrate toxicosis in beef and dairy cattle herds due to contamination of drinking water and whey.

    Science.gov (United States)

    Yeruham, I; Shlosberg, A; Hanji, V; Bellaiche, M; Marcus, M; Liberboim, M

    1997-10-01

    Four cases of rarely reported nitrate toxicosis due to contamination of drinking water or whey were recorded in 2 beef and 2 dairy cattle herds. In the cases associated with water contamination, water containing ammonium nitrate as a fertilizer for irrigating orchards accidentally entered drinking water troughs for cattle through malfunctioning 1-way valves. The whey contamination in 1 instance was caused by transportation in containers which contained traces of concentrated ammonium nitrate; the 2nd case was induced by whey derived from the production of a specialty cheese produced by the incorporation of nitrate. Mortality occurred in 2 herds and abortions in the 2 other herds. Affected cows responded well to treatment, but some animals remained in a deteriorated physical condition for several months.

  8. Hydrodynamic effects on contaminants release due to rususpension and diffu-sion from sediments

    Institute of Scientific and Technical Information of China (English)

    朱红伟; 程鹏达; 钟宝昌; 王道增

    2013-01-01

    Hydrodynamic effects play a very important role in the contaminants release from sediments. Experiments were perfor-med to study contaminants releasing characteristics due to resuspension. The time-dependent variation of COD concentration and re-lative roles under static and dynamic state of the overlying water were analyzed. Experimental results showed that COD concen-tration in the water column got a striking increment on the dynamic conditions, mainly by reducing the thickness of concentration boundary layer near sediment-water interface and destructing the surface structure of sediment. Hydrodynamics increased contamina-nts release rates and flux in unit time. Before reaching an equilibrium stage, the dynamic release caused by the resuspension was more effective than static one due to molecular diffusion. The release rate of COD increased with flow velocity and decreased with water depth. But at a shallow water depth, wave effects would dominate the causing resuspension, resulting in contaminants release in large quantity. The intensity of pollutant release increased with time in a rather circuitous process. The diffusion of pollutant from internal sediment to the sediment-water interface would maintain the endogenous release effects.

  9. Imbalance of Nature due to Contaminant Loads in the Culiacan River Watershed, Sinaloa, México

    Science.gov (United States)

    García Páez, F.; Ley-Aispuro, E.

    2013-05-01

    The Culiacan River discharges runoff from a large agricultural watershed into the wetlands at Ensenada de Pabellones ranked as a priority marine region of Mexico due to its high biodiversity and the economic importance of its fishing resources. This research estimated potential contaminant loads for BOD5, TSS, N and P from stormwater runoff and associated land use in the watershed. Previous studies had demonstrated the imbalance of nature due to land use change causing contamination by heavy metals, pesticides, sediment, phosphorus and eutrophication (Lopez and Osuna, 2002; Green and Paez, 2004, Gonzalez et al., 2006; Osuna et al., 2007). The methodology included: Characterizing the watershed according to land use, soil, vegetation, annual runoff and population density by sub-watershed; estimating the potential contaminant load and annual average concentrations of contaminants using the PLOAD program, comparing the result with monitored contaminant concentrations; and identifying the impact of pollutant loads in the watershed and coastal ecosystems and proposing management strategies to reduce or reverse the imbalance of nature caused by contamination in the Culiacan River watershed. Calculated contaminant loads in tonne/year were 13,682.4 of BOD5; 503,621.8 of TSS; 5,975.7 of N and 1,789.1 of P. The Tamazula and Humaya rivers watersheds provide 72% of the total load of BOD5, 68.5% of TSS, 77.6% of N and 62.7% of P discharged to the wetlands. Monitored results include: 89% of temperature observations were above 21°C, which is stressful to aquatic life due to a subsequent decrease in dissolved oxygen; 100% of the observations of P exceeded the ecological criteria for water quality; 71.5% of the observations for DO from 2001 to 2011, were above the ecological criteria for protection of aquatic life and 91.5% met the criteria for use in drinking water; 100% of the observations for BOD5 values remained in the range of Excellent to Good; 22% of the observations for the

  10. AIR QUALITY DETERIORATION IN TEHRAN DUE TO MOTORCYCLES

    Directory of Open Access Journals (Sweden)

    M. Shafiepour and H. Kamalan

    2005-07-01

    Full Text Available Since there is a rise of motorcycles population as well as other motor vehicles, it seems that air Pollution deterioration should be studied as one of its environmental impacts. The main objective of this study was to develop a number of scenarios in order to determine the amount of Tehran's air pollution attributable to motorcycles and select the best and the most probable case to be recommended for implementation. The first step was to collect data such as the number of active motorcycles, daily traffic volume, average traveling speed and actual emission factors. For this purpose, a detailed questionnaire was designed to be completed by field surveys and measurements. The collected data were compared with traffic volume data, manufacturing statistics and the latest production capacity forecast in this field. Finally, with this data and emission factors for each type of motorcycle, an emissions inventory model was chosen to provide annual emissions from motorcycles in Tehran in different scenarios. The results showed that in 2002, there has been about 450'000 active motorcycles (4-stroke 58%, 2-stroke 28%, and moped 14% with average speed of 40 km/h and average mileage of 110 km/d. Five scenarios were developed. The best scenario was "Changing all motorcycles to 4-strokes under EU-97 standard" which would result in reduction of NMVOC by 75%, CO by 35% and PM10 by 88%.

  11. Generation of Overpressure due to Condensation in Moist Air Jet

    Institute of Scientific and Technical Information of China (English)

    Yumiko OTOBE; Hideo KASHIMURA; Shigeru MATSUO; Masanori TANAKA; Toshiaki SETOGUCHI

    2007-01-01

    In the present study, a computational fluid dynamics method has been applied to investigate the effects of initial degree of supersaturation at reservoir condition on under-expanded sonic jet structures, such as Mach disk location and diameter, barrel shock wave and jet boundary. The axisymmetric nozzle geometry investigated was a converging nozzle with straight part. As a result, it was found that the overpressures due to condensation generate and the characteristics of flow with generation of overpressure due to condensation in the jet were different from those without condensation.

  12. The risk of river pollution due to washout from contaminated floodplain water bodies during high floods

    Science.gov (United States)

    Lyubimova, Tatyana; Lepikhin, Anatoly; Parshakova, Yanina; Tiunov, Alexey

    2016-04-01

    Today, the potential impact of extremely high floods, which in the last years have become a rather frequent weather-related disaster, is the problem of primary concern. In studies of the potential impact of floods the emphasis is placed first of all on the estimation of possible flood zones and the analysis of the flow regimes in these zones. However, in some cases the hydrochemical parameters related to changes in the chemical composition of water are more important than the hydraulic parameters. It is generally believed that the higher is the flow rate, the more intensive is the process of dissolution, i.e. the lower is the concentration of limiting contaminants in water. However, this statement is valid provided that flooding does not activate new sources of water pollution such as contaminated floodplain water bodies located in the vicinity of water supply systems. Being quite reliable and safe at small and moderate discharges, in the case of extremely high level of river waters they become intensive sources of water pollution, essentially limiting the water consumption schedule for downstream water consumers. It should be noted that compared to the well-studied mechanisms of waste discharge due to failure of hydraulic engineering structures by flood waves, the mechanisms of pollutant washout from the contaminated floodplain water bodies by the flood waves is still poorly understood. We analyze the impacts of such weather-related events on the quality of water in the water intake system, taking as an example, the section of the Vyatka River located in the Prikamskaya lowland of the Russian Federation. The risk of river pollution due to washout from the contaminated floodplain water bodies during high floods is studied by hydrodynamical modeling in the framework of combined approach using one-, two- and three-dimensional hydrodynamic models are implemented and by in situ measurements. It is shown that during high floods the removal of pollutants from the

  13. Air pollution and health risks due to vehicle traffic

    Science.gov (United States)

    Zhang, Kai; Batterman, Stuart

    2014-01-01

    Traffic congestion increases vehicle emissions and degrades ambient air quality, and recent studies have shown excess morbidity and mortality for drivers, commuters and individuals living near major roadways. Presently, our understanding of the air pollution impacts from congestion on roads is very limited. This study demonstrates an approach to characterize risks of traffic for on- and near-road populations. Simulation modeling was used to estimate on- and near-road NO2 concentrations and health risks for freeway and arterial scenarios attributable to traffic for different traffic volumes during rush hour periods. The modeling used emission factors from two different models (Comprehensive Modal Emissions Model and Motor Vehicle Emissions Factor Model version 6.2), an empirical traffic speed–volume relationship, the California Line Source Dispersion Model, an empirical NO2–NOx relationship, estimated travel time changes during congestion, and concentration–response relationships from the literature, which give emergency doctor visits, hospital admissions and mortality attributed to NO2 exposure. An incremental analysis, which expresses the change in health risks for small increases in traffic volume, showed non-linear effects. For a freeway, “U” shaped trends of incremental risks were predicted for on-road populations, and incremental risks are flat at low traffic volumes for near-road populations. For an arterial road, incremental risks increased sharply for both on- and near-road populations as traffic increased. These patterns result from changes in emission factors, the NO2–NOx relationship, the travel delay for the on-road population, and the extended duration of rush hour for the near-road population. This study suggests that health risks from congestion are potentially significant, and that additional traffic can significantly increase risks, depending on the type of road and other factors. Further, evaluations of risk associated with congestion

  14. Air pollution and health risks due to vehicle traffic.

    Science.gov (United States)

    Zhang, Kai; Batterman, Stuart

    2013-04-15

    Traffic congestion increases vehicle emissions and degrades ambient air quality, and recent studies have shown excess morbidity and mortality for drivers, commuters and individuals living near major roadways. Presently, our understanding of the air pollution impacts from congestion on roads is very limited. This study demonstrates an approach to characterize risks of traffic for on- and near-road populations. Simulation modeling was used to estimate on- and near-road NO2 concentrations and health risks for freeway and arterial scenarios attributable to traffic for different traffic volumes during rush hour periods. The modeling used emission factors from two different models (Comprehensive Modal Emissions Model and Motor Vehicle Emissions Factor Model version 6.2), an empirical traffic speed-volume relationship, the California Line Source Dispersion Model, an empirical NO2-NOx relationship, estimated travel time changes during congestion, and concentration-response relationships from the literature, which give emergency doctor visits, hospital admissions and mortality attributed to NO2 exposure. An incremental analysis, which expresses the change in health risks for small increases in traffic volume, showed non-linear effects. For a freeway, "U" shaped trends of incremental risks were predicted for on-road populations, and incremental risks are flat at low traffic volumes for near-road populations. For an arterial road, incremental risks increased sharply for both on- and near-road populations as traffic increased. These patterns result from changes in emission factors, the NO2-NOx relationship, the travel delay for the on-road population, and the extended duration of rush hour for the near-road population. This study suggests that health risks from congestion are potentially significant, and that additional traffic can significantly increase risks, depending on the type of road and other factors. Further, evaluations of risk associated with congestion must

  15. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.

  16. Report of Findings: Cold Bay Air Force Station (Grant Point) military contaminants: Fiscal year 1988 collections

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes our contaminants investigation at the abandoned Cold Bay Air Force Station (Station), located on the Izembek National Wildlife Refuge at Grant...

  17. CONTAMINATION OF GROUNDWATER IN SRIKAKULAM COASTAL BELT DUE TO SALT WATER INTRUSION

    Directory of Open Access Journals (Sweden)

    S. Chandra Mouli

    2011-02-01

    Full Text Available Many urban centers of the country are located on the coastal tract apart from thousands of villages and industrial settlements. Water resources in coastal areas assume a special significance since anydevelopmental activity will largely depend upon availability of fresh water to meet domestic, industrial and agricultural requirements.Thisincreases the dependency upon groundwater for meeting the freshwater demand. As the region is close to the coast, the variations in the levels of water table due to excess withdrawals from wells and bore wells will cause the intrusion of seawater into the groundwater. In the present paper deals with the study of saltwater intrusion in the coastal tract of Srikakulam district, on an areal basis. From the results obtained the variation in the effect of contamination with respect to distance from shore is studied and a comparison of the contamination in open wells and bore wells is also carried out.

  18. Study on influence of characteristics of air-supply jet on drain contamination efficiency and air quality in heading

    Institute of Scientific and Technical Information of China (English)

    LIU He-qing; SHI Shi-liang; LIU Rong-hua; WANG H ai-qiao

    2001-01-01

    Based on the theory of air-supply jet, the conception and theory o f the air quality and the drain-contamination efficiency, the results achieved b y comparing the circular cross-section wall jet with the plane wall jet were fo l lowing: firstly, within the limitation of the ventilation distance at the tunnel heading in a coal mine, there were a better air quality and a higher efficiency of drain-contamination with application of the plane wall jet ventilation. Sec o ndly, there was a advantage to improve the air quality of the workers breathin g area with mounting the air-supply outlet on the top but not on the side of the tunnel heading.

  19. Spatiotemporal variability of tetrachloroethylene in residential indoor air due to vapor intrusion: a longitudinal, community-based study.

    Science.gov (United States)

    Johnston, Jill E; Gibson, Jacqueline MacDonald

    2014-11-01

    The migration of volatile contaminants from groundwater and soil into indoor air is a potential health threat at thousands of contaminated sites across the country. This phenomenon, known as vapor intrusion, is characterized by spatial and temporal heterogeneity. This study examined short-term fluctuations in concentrations of tetrachloroethylene (PCE) in the indoor air of residential homes due to vapor intrusion in a community in San Antonio, Texas, that sits atop an extensive, shallow plume of contaminated groundwater. Using a community-based design, we removed potential indoor sources of PCE and then collected twelve 3-day passive indoor air samples in each of the 20 homes. Results demonstrated a one-order-of-magnitude variability in concentration across both space and time among the study homes, although all measured concentrations were below risk-based screening levels. We found that within any given home, indoor concentrations increase with the magnitude of the barometric pressure drop (P=0.048) and humidity (P<0.001), while concentrations decrease as wind speed increases (P<0.001) and also during winter (P=0.001). In a second analysis to examine sources of spatial variability, we found that indoor air PCE concentrations between homes increase with groundwater concentration (P=0.030) and a slab-on-grade (as compared with a crawl space) foundation (P=0.028), whereas concentrations decrease in homes without air conditioners (P=0.015). This study offers insights into the drivers of temporal and spatial variability in vapor intrusion that can inform decisions regarding monitoring and exposure assessment at affected sites.

  20. Status of radiation dose and radioactive contamination due to the Fukushima accident

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Mamoru [Tohoku Univeristy, Sendai (Japan)

    2016-06-15

    The accident at Fukushima Daiichi Nuclear Power Plant (NPP), March 2011, caused serious radioactive contamination over wide area in east Japan. Therefore, it is important to know the effect of the accident and the status of NPP. This paper provides a review on the status of radiation dose and radioactive contamination caused by the accident on the basis of publicized information. Monitoring of radiation dose and exposure dose of residents has been conducted extensively by the governments and various organizations. The effective dose of general residents due to the accident proved to be less than a mSv both for external and internal dose. The equivalent committed dose of thyroid was evaluated to be a few mSv in mean value and less than 50 mSv even for children. Monitoring of radioactivity concentration has been carried out on food ingredients, milk and tap water, and actual meal. These studies indicated the percentage of foods above the regulation standard was over 10% in 2011 but decreasing steadily with time. The internal dose due to foods proved to be tens of μSv and much less than that due to natural {sup 40}K even in the Fukushima area and decreasing steadily, although high level concentration is still observed in wild plants, wild mushrooms, animals and some kind of fishes. According to extensive studies, not only the effect of the accident but also the pathway and countermeasures against radioactive contamination have been revealed, and they are applied very effectively for restoration of environment and reconstruction of the area.

  1. Moisture Risk in Unvented Attics Due to Air Leakage Paths

    Energy Technology Data Exchange (ETDEWEB)

    Prahl, D. [IBACOS, Inc., Pittsburgh, PA (United States); Shaffer, M. [IBACOS, Inc., Pittsburgh, PA (United States)

    2014-11-01

    IBACOS completed an initial analysis of moisture damage potential in an unvented attic insulated with closed-cell spray polyurethane foam. To complete this analysis, the research team collected field data, used computational fluid dynamics to quantify the airflow rates through individual airflow (crack) paths, simulated hourly flow rates through the leakage paths with CONTAM software, correlated the CONTAM flow rates with indoor humidity ratios from Building Energy Optimization software, and used Wärme und Feuchte instationär Pro two-dimensional modeling to determine the moisture content of the building materials surrounding the cracks. Given the number of simplifying assumptions and numerical models associated with this analysis, the results indicate that localized damage due to high moisture content of the roof sheathing is possible under very low airflow rates. Reducing the number of assumptions and approximations through field studies and laboratory experiments would be valuable to understand the real-world moisture damage potential in unvented attics.

  2. Moisture Risk in Unvented Attics Due to Air Leakage Paths

    Energy Technology Data Exchange (ETDEWEB)

    Prahl, D.; Shaffer, M.

    2014-11-01

    IBACOS completed an initial analysis of moisture damage potential in an unvented attic insulated with closed-cell spray polyurethane foam. To complete this analysis, the research team collected field data, used computational fluid dynamics to quantify the airflow rates through individual airflow (crack) paths, simulated hourly flow rates through the leakage paths with CONTAM software, correlated the CONTAM flow rates with indoor humidity ratios from Building Energy Optimization software, and used Warme und Feuchte instationar Pro two-dimensional modeling to determine the moisture content of the building materials surrounding the cracks. Given the number of simplifying assumptions and numerical models associated with this analysis, the results indicate that localized damage due to high moisture content of the roof sheathing is possible under very low airflow rates. Reducing the number of assumptions and approximations through field studies and laboratory experiments would be valuable to understand the real-world moisture damage potential in unvented attics.

  3. Contact angles at the water-air interface of hydrocarbon-contaminated soils and clay minerals

    Science.gov (United States)

    Sofinskaya, O. A.; Kosterin, A. V.; Kosterina, E. A.

    2016-12-01

    Contact angles at the water-air interface have been measured for triturated preparations of clays and soils in order to assess changes in their hydrophobic properties under the effect of oil hydrocarbons. Tasks have been to determine the dynamics of contact angle under soil wetting conditions and to reveal the effect of chemical removal of organic matter from soils on the hydrophilicity of preparations. The potentialities of static and dynamic drop tests for assessing the hydrophilic-hydrophobic properties of soils have been estimated. Clays (kaolinite, gumbrine, and argillite) have been investigated, as well as plow horizons of soils from the Republic of Tatarstan: heavy loamy leached chernozem, medium loamy dark gray forest soil, and light loamy soddy-calcareous soil. The soils have been contaminated with raw oil and kerosene at rates of 0.1-3 wt %. In the uncontaminated and contaminated chernozem, capillary water capacity has been maintained for 250 days. The contact angles have been found to depend on the degree of dispersion of powdered preparation, the main type of clay minerals in the soil, the presence and amount of oxidation-resistant soil organic matter, and the soil-water contact time. Characteristic parameters of mathematical models for drop behavior on triturated preparations have been calculated. Contamination with hydrocarbons has resulted in a reliable increase in the contact angles of soil preparations. The hydrophobization of soil surface in chernozem is more active than in soils poorer in organic matter. The complete restoration of the hydrophilic properties of soils after hydrocarbon contamination is due to the oxidation of easily oxidizable organic matter at the low content of humus, or to wetting during several months in the absence of the mazut fraction.

  4. Lichen (Xanthoria parietina) biomonitoring of trace element contamination and air quality assessment in Livorno Province (Tuscany, Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Scerbo, R.; Barghigiani, C.; Ristori, T. [CNR Istituto di Biofisica, Via S. Lorenzo 26, 56127 Pisa (Italy); Possenti, L.; Barale, R. [Dipartimento di Scienze dell' Ambiente e del Territorio, Via Volta, Pisa (Italy); Lampugnani, L. [CNR Istituto di Chimica Analitica Strumentale, Via Risorgimento, Pisa (Italy)

    1999-10-29

    This paper deals with the biomonitoring of air in Livorno Province (Tuscany, Italy) using lichens for both quantitative monitoring of airborne metals and air quality assessment. On the basis of the possible sources of metal pollution in the study area, the following elements were analyzed: As, Cd, Cr, Ni, Pb, V, Zn and Hg. The small number of lichen species, the often stunted appearance of the specimens, and metal analysis revealed widespread atmospheric pollution in the study area. The results indicate extensive anthropic impact. The highest levels of contamination were recorded for Hg, Cd, Pb, and V concentrations. Good agreement was found between bioindication and metal concentrations in lichens. The impact of anthropic activities is particularly due to steelworks and chemical plants, combustion processes related to energy production and vehicle emissions. In addition to air pollution, some natural factors, such as climate, rocky shores or ozone, were assumed to affect lichen occurrence. Comparison with the Lake Orta area in northern Italy showed Livorno Province was more contaminated by trace elements. Similar contamination levels were found in another area of Tuscany, probably due to the geological characteristics of this region.

  5. [Ambient and enclosed space air sampling for determination of contaminants].

    Science.gov (United States)

    Dorogova, V B

    2010-01-01

    The paper touches upon the issues how to correctly and maximally take single and average daily samples of ambient, residential and public building, and enclosed space air for further tests for the content of hazardous substances. The paper is debated.

  6. Thermal air contamination in urban environment. Contaminacion termica del aire en el medio ambiente urbano

    Energy Technology Data Exchange (ETDEWEB)

    Munoz Machado, A.

    1994-01-01

    This article summarizes the necessity of thermal contamination control. The principal contaminant is the loss of heat from buildings. There is not a regulation and the environmental regulation has not a special article to regulate this topic.

  7. Fatal Intoxications Due to Administration of Isosorbide Tablets Contaminated with Pyrimethamine.

    Science.gov (United States)

    Imran, Muhammad; Shafi, Humera; Mahmood, Zahid; Sarwar, Mohammad; Usman, Hafiz Faisal; Tahir, Mohammad Ashraf; Ashiq, Muhammad Zar

    2016-09-01

    In January 2012, 664 cases of pyrimethamine toxicity and 151 deaths were reported among cardiac patients that had recently received free medicines from pharmacy of Punjab Institute of Cardiology, Lahore, Pakistan. These patients, ages ranged from 58 to 75 years, were prescribed simvastatin, clopidogrel, aspirin soluble, isosorbide mononitrate, and amlodipine. On examination of medications being given to them, it was found that a particular batch of isosorbide mononitrate tablets was contaminated with 50 mg pyrimethamine. Cardiac patients were taking isosorbide contaminated with pyrimethamine twice daily (100 mg pyrimethamine/day), whereas therapeutic dose of pyrimethamine for malaria is 25 mg/week. Postmortem urine, cardiac blood, and femoral blood specimens of three deceased males were submitted to author's laboratory for analysis. Postmortem toxicological analysis revealed that pyrimethamine concentration fell within the range of 1-10 μg/mL by liquid chromatography. Clinical, autopsy, histopathological, and toxicological findings strongly suggested toxicity due to pyrimethamine accumulation that resulted in deaths of these cardiac patients.

  8. 40 CFR 86.166-12 - Method for calculating emissions due to air conditioning leakage.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Method for calculating emissions due to air conditioning leakage. 86.166-12 Section 86.166-12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for...

  9. Preparation to the CMB Planck analysis : contamination due to the polarized galactic emission

    CERN Document Server

    Fauvet, L

    2010-01-01

    The Planck satellite experiment, which was launched the 14th of may 2009, will give an accurate measurement of the anisotropies of the Cosmic Microwave Background (CMB) in temperature and polarization. This measurement is polluted by the presence of diffuse galactic polarized foreground emissions. In order to obtain the level of accuracy required for the Planck mission it is necessary to deal with these foregrounds. In order to do this, have develloped and implemented coherent 3D models of the two main galactic polarized emissions : the synchrotron and thermal dust emissions. We have optimized these models by comparing them to preexisting data : the K-band of the WMAP data, the ARCHEOPS data at 353 GHz and the 408 MHz all-sky continuum survey. By extrapolation of these models at the frequencies where the CMB is dominant, we are able to estimate the contamination to the CMB Planck signal due to these polarized galactic emissions.

  10. Quantitative-spatial assessment of soil contamination in S. Francisco de Assis due to mining activity of the Panasqueira mine (Portugal).

    Science.gov (United States)

    Ferreira da Silva, Eduardo; Freire Ávila, Paula; Salgueiro, Ana Rita; Candeias, Carla; Garcia Pereira, Henrique

    2013-11-01

    Through the years, mining and beneficiation processes produces large amounts of As-rich mine wastes laid up in huge tailings and open-air impoundments (Barroca Grande and Rio tailings) that are the main source of pollution in the surrounding area once they are exposed to the weathering conditions leading to the formation of AMD and consequently to the contamination of the surrounding environments, in particularly soils. In order to investigate the environmental contamination impact on S. Francisco de Assis (village located between the two major impoundments and tailings) agricultural soils, a geochemical survey was undertaken to assess toxic metals associations, related levels and their spatial distribution, and to identify the possible contamination sources. According to the calculated contamination factor, As and Zn have a very high contamination factor giving rise to 65.4% of samples with a moderate to high pollution degree; 34.6% have been classified as nil to very low pollution degree. The contamination factor spatial distribution put in evidence the fact that As, Cd, Cu, Pb, and Zn soils contents, downstream Barroca Grande tailing, are increased when compared with the local Bk soils. The mechanical dispersion, due to erosion, is the main contamination source. The chemical extraction demonstrates that the trace metals distribution and accumulation in S. Francisco de Assis soils is related to sulfides, but also to amorphous or poorly crystalline iron oxide phases. The partitioning study allowed understanding the local chemical elements mobility and precipitation processes, giving rise to the contamination dispersion model of the study area. The wind and hydrological factors are responsible for the chemical elements transport mechanisms, the water being the main transporter medium and soils as one of the possible retention media.

  11. INTEGRATION OF PHOTOCATALYTIC OXIDATION WITH AIR STRIPPING OF CONTAMINATED AQUIFERS

    Science.gov (United States)

    Bench scale laboratory studies and pilot scale studies in a simulated field-test situation were performed to evaluate the integration of gas-solid ultaviolet (UV) photocatalytic oxidation (PCO) downstream if an air stripper unit as a technology for cost-effectively treating water...

  12. An indoor air aerosol model for outdoor contaminant transmission into occupied rooms

    Institute of Scientific and Technical Information of China (English)

    XIE Hui; ZHAO Shen; CAO Guo-qing

    2014-01-01

    The paper presents a simple model for outdoor air contaminant transmission into occupied rooms. In the model, several factors such as filtration, ventilation, deposition, re-emission, outdoor concentration and indoor sources are included. The model results show that the air exchange rate plays an important role in the transmission of outdoor contaminants into the indoor environment. The model shows that increasing the value of the filtration efficiency decreases the mass concentration of indoor particles. In addition, if outdoor aerosol particles have a periodic behaviour, indoor aerosol particles also behave periodically but smoother. Indoor sources are found to be able to increase indoor concentrations greatly and continuously.

  13. [Quality of interior air: biological contaminants and their effects on health; bioaerosols and gathering techniques].

    Science.gov (United States)

    Bălan, Gabriela

    2007-01-01

    Indoor Air Quality: biological contaminants and health effects; airborne organisms and sampling instruments. Biological contaminants include bacteria, molds, viruses, animal dander and cat saliva, house dust, mites, cockroaches and pollen. Symptoms of health problems caused by biological pollutants include sneezing, watery eyes, coughing, shortness of breath, dizziness, lethargy, fevers. Children, elderly people with breathing problems, allergies and lung diseases are particularly susceptible to disease-causing biological agents in the indoor air. It is convenient to consider microbiological samplers for collecting organisms in air as falling into several broad categories. Many popular microbiological air samplers use the principle of impaction to trap the organisms by impacting them directly on to agar. Further distinct groups are the impingers, which operate by impinging organisms into liquid.

  14. Data mining of plasma peptide chromatograms for biomarkers of air contaminant exposures

    Directory of Open Access Journals (Sweden)

    Vincent Renaud

    2008-01-01

    Full Text Available Abstract Background Interrogation of chromatographic data for biomarker discovery becomes a tedious task due to stochastic variability in retention times arising from solvent and column performance. The difficulty is further compounded when the effects of exposure (e.g. to environmental contaminants and biological variability result in varying numbers and intensities of peaks among chromatograms. Results We developed a software tool to correct the stochastic time shifts in chromatographic data through iterative selection of landmark peaks and isometric interpolation to improve alignment of all chromatographic peaks. To illustrate application of the tool, plasma peptides from Fischer rats exposed for 4 h to clean air or Ottawa urban particles (EHC-93 were separated by HPLC with autofluorescence detection, and the retention time shifts between chromatograms were corrected (dewarped. Both dewarped and non-dewarped datasets were then mined for models containing peptide peaks that best discriminate among the treatment groups using ClinproTools™. In general, models generated by dewarped datasets were able to better classify test sample chromatograms into either clean air or EHC-93 exposure groups, and 0 or 24 h post-recovery time groups. Peak areas of peptides in a model that produced the best discrimination of treatment groups were analyzed by two-way ANOVA with exposure (clean air, EHC-93 and recovery time (0 h, 24 h as factors. Statistically significant (p Conclusion Our software tool provides a simple and portable approach for alignment of chromatograms with complex, bi-directional retention time shifts prior to data mining. Reliable biomarker discovery can be achieved through chromatographic dewarping using our software followed by pattern recognition by commercial data mining applications.

  15. Remediation in Situ of Hydrocarbons by Combined Treatment in a Contaminated Alluvial Soil due to an Accidental Spill of LNAPL

    Directory of Open Access Journals (Sweden)

    Ettore Trulli

    2016-10-01

    Full Text Available Soil contamination represents an environmental issue which has become extremely important in the last decades due to the diffusion of industrial activities. Accidents during transport of dangerous materials and fuels may cause severe pollution. The present paper describes the criteria of the actions which were operated to remediate the potential risk and observed negative effects on groundwater and soil originating from an accidental spill of diesel fuel from a tank truck. With the aim to evaluate the quality of the involved environmental matrices in the “emergency” phase, in the following “safety” operation and during the remediation action, a specific survey on hydrocarbons, light and heavy, was carried out in the sand deposits soil. Elaboration of collected data allows us to observe the movement of pollutants in the unsaturated soil. The remediation action was finalized to improve the groundwater and soil quality. The former was treated by a so called “pump and treat” system coupled with air sparging. A train of three different technologies was applied to the unsaturated soil in a sequential process: soil vapour extraction, bioventing and enhanced bioremediation. Results showed that the application of sequential remediation treatments allowed us to obtain a state of quality in unsaturated soil and groundwater as required by Italian law.

  16. Evaluation of air pollution due to natural radioactive elements; Evaluacion de contaminacion del aire debido a elementos radiactivos naturales

    Energy Technology Data Exchange (ETDEWEB)

    Perez, B. A.; Lopez, M. E., E-mail: bertin.perez@pucp.edu.pe [Pontificia Universidad Catolica del Peru, Seccion Fisica, Av. Universitaria 1801, San Miguel, Lima (Peru)

    2014-08-15

    The presence of radioactive materials in the crustal and as consequence present in the surface, originate the natural radioactive contamination in the different solid, liquid and gaseous materials; particularly in the air that we breathe. Among these radioactive materials that contribute to the environmental pollution are the presences of uranium, radio, thorium and their respective disintegration chains, as the gas radon (Rn-222) that spreads in the air; whose presence increases in areas where the seismic activity is notorious or other natural events take place, case of the Lima (Peru) City. In this work we show the measurements realized during two consecutive years in the roof of a building of three floors in the Lima City, with the purpose of establishing the fluctuations of this gassy pollutant in the surrounding air. The measurements were made using nitrocellulose detectors (Lr-115 type 2) applying the nuclear prints technique. The obtained results allowing to have an indicator of the Rn-222 presence in the air during different seasons of the year and also the presence of other possible radioactive pollutants. The use of this technique allows obtaining and studying the prints that generate the alpha particles that are emitted during the Rn-222 disintegration or by means of their descendants or predecessors; also allowing to discriminate between the short-range tracers or lineal type prints and other very different prints obtained during some of the measurements. The results analyzed according to proposed models are presented in this work. (author)

  17. Impacts of contaminant storage on indoor air quality: Model development

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Max H.; Hult, Erin L.

    2013-02-26

    A first-order, lumped capacitance model is used to describe the buffering of airborne chemical species by building materials and furnishings in the indoor environment. The model is applied to describe the interaction between formaldehyde in building materials and the concentration of the species in the indoor air. Storage buffering can decrease the effect of ventilation on the indoor concentration, compared to the inverse dependence of indoor concentration on the air exchange rate that is consistent with a constant emission rate source. If the exposure time of an occupant is long relative to the time scale of depletion of the compound from the storage medium, however, the total exposure will depend inversely on the air exchange rate. This lumped capacitance model is also applied to moisture buffering in the indoor environment, which occurs over much shorter depletion timescales of the order of days. This model provides a framework to interpret the impact of storage buffering on time-varying concentrations of chemical species and resulting occupant exposure. Pseudo-steady state behavior is validated using field measurements. Model behavior over longer times is consistent with formaldehyde and moisture concentration measurements in previous studies.

  18. PECULIARITIES OF CURRENT DOSE ASSESSMENT FOR CHILDREN LIVING IN THE TERRITORIES RADIOACTIVELY CONTAMINATED DUE TO THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    A. V. Gromov

    2011-01-01

    Full Text Available The article outlines peculiarities of current dose assessment for the children living in the territories radioactively contaminated due to the Chernobyl accident. The results of annual exposure dose assessment for the children of various age groups and adult population of three subject territories of the Russian Federation referred to the zones of radioactive contamination are presented. A comparison of obtained estimations is done.

  19. Effect of Air Pollution, Contamination and High Altitude on Bronchial Asthma

    Directory of Open Access Journals (Sweden)

    Nesriene El margoushy*, Mohamad El Nashar**, Hatem Khairy*, Nihad El Nashar*, Hala Mohamad

    2013-01-01

    Full Text Available Epidemiological studies have shown that the prevalence of asthma has risen dramatically worldwide and evidence suggests that environmental factors have an important role in the etiology of the disease. Most respiratory diseases are caused by airborne agents. Our lungs are uniquely vulnerable to contamination from the air we breathe. Air pollution exposure is associated with increased asthma and allergy morbidity and is a suspected contributor to the increasing prevalence of allergic conditions. Observational studies continue to strengthen the association between air pollution and allergic respiratory disease. The effects of air pollution should be viewed in two different groups: healthy people and people with chronic heart or lung disease. Although the fundamental causes of asthma are not completely understood, the strongest risk factors for developing asthma are inhaled asthma triggers. These include: indoor allergens (for example house dust mites in bedding, carpets and stuffed furniture, pollution and pet dander, outdoor allergens (such as pollens and moulds, tobacco smoke and chemical irritants in the workplace. Other triggers can include cold air, extreme emotional arousal such as anger or fear, and physical exercise. Even certain medications can trigger asthma such as aspirin and other non-steroid anti-inflammatory drugs, and beta-blockers. Urbanization has also been associated with an increase in asthma; however the exact nature of this relationship is unclear. Medication is not the only way to control asthma. It is also important to avoid asthma triggers - stimuli that irritate and inflame the airways. Prevalence of asthma is generally low within the Middle East, although high rates have been recorded in the Kingdom of Saudi Arabia, Kuwait, Lebanon, and Israel. The prevalence of asthma and asthma-related symptoms is high among 16- to 18-year-old adolescents in Saudi Arabia, and the symptoms are more common in boys than in girls

  20. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    This report presents information related to the sampling of ground water at the Wright-Patterson Air Force Base. It is part of an investigation into possible ground water contamination. Information concerns well drilling/construction; x-ray diffraction and sampling; soil boring logs; and chain-of-custody records.

  1. Environmental contaminants in golden shiners from Picnic Pond, U.S. Naval Air Station, Brunswick, Maine

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — On July 25, 1995, the U.S. Fish and Wildlife Service conducted a contaminant survey of fish from Picnic Pond on the U.S. Naval Air Station in Brunswick, Maine...

  2. Aflatoxin B1 contamination in maize in Europe increases due to climate change

    Science.gov (United States)

    Battilani, P.; Toscano, P.; van der Fels-Klerx, H. J.; Moretti, A.; Camardo Leggieri, M.; Brera, C.; Rortais, A.; Goumperis, T.; Robinson, T.

    2016-04-01

    Climate change has been reported as a driver for emerging food and feed safety issues worldwide and its expected impact on the presence of mycotoxins in food and feed is of great concern. Aflatoxins have the highest acute and chronic toxicity of all mycotoxins; hence, the maximal concentration in agricultural food and feed products and their commodities is regulated worldwide. The possible change in patterns of aflatoxin occurrence in crops due to climate change is a matter of concern that may require anticipatory actions. The aim of this study was to predict aflatoxin contamination in maize and wheat crops, within the next 100 years, under a +2 °C and +5 °C climate change scenario, applying a modelling approach. Europe was virtually covered by a net, 50 × 50 km grids, identifying 2254 meshes with a central point each. Climate data were generated for each point, linked to predictive models and predictions were run consequently. Aflatoxin B1 is predicted to become a food safety issue in maize in Europe, especially in the +2 °C scenario, the most probable scenario of climate change expected for the next years. These results represent a supporting tool to reinforce aflatoxin management and to prevent human and animal exposure.

  3. Fish contamination with DDT due to malaria control in the Brazilian Amazon

    Energy Technology Data Exchange (ETDEWEB)

    Torres, J.P.M.; Meire, R.; Azeredo, A.; Malm, O. [Lab. de Radiosotopos Eduardo Penna Franca, IBCCF - UFRJ, RJ (Brazil); D' Amato, C. [Programa de Pos Graduacao em Ciencias dos Alimentos, IQ-UFRJ, RJ (Brazil); Saldanha, G.; Bastos, W. [Lab. de Biogeoquimica, UNIR, Porto Velho (Brazil); Claudio, L. [International Training Environmental Medicine, The Mount Sinai School of Medicine, Community and Preventive Medicine Dept., NY (United States); Markowitz, S. [Center for Biology of the Natural Systems, Queens Coll. New York (United States)

    2004-09-15

    The DDT, a term used to refer to Dichlorodiphenyltrichloroethane, is an organochlorine pesticide first synthesized in 1874, but its properties as insecticide were discovered only in the late 1930's by the chemist Paul Muller, who won the Nobel Prize in 1948. Since its discovery, DDT use revolutionized the control concepts against malaria and other tropical insect-borne diseases. A large-scale industrial production started in 1943 and it was used in great quantities mainly for the agricultural and forest pest control. A smaller quantity of the world production (20-30%) was used in tropical disease control. In 1946 it was established a regular system of DDT applications in Amazon houses. Its use became common in malaria vector control and other tropical diseases, like leishmaniasis. DDT began to be restricted after the discovery of its toxicity against wild animals, especially top predators and due to potential toxic effects against humans. The DDT restrictive measures in Brazil started in 19714. In 1985 DDT was prohibited for agricultural purposes, but continued to be use for Public Health Campaigns, under the responsibility of FUNASA, the Brazilian National Health Foundation. An investigation conducted by Vieira et al. detected {sigma}ODDT in soil, sediments and chicken eggs from an area seven and nine years after its last application for leishmaniasis vector control near the sprayed sites. Today DDT is recognized as one of the twelve Persistent Organic Pollutants - POPs. Concerning DDT in food, based on clinical observations as well as experimental animals, the annual Joint FAO/WHO Meetings on Pesticide Residues held in 20008 estimated a Provisional Tolerable Daily Intake (PTDI) for DDT in 0.01 mg/kg/day. Marien and Laflamme9 have proposed a Tolerable Daily Intake (TDI) for breast feedings infants of 5 x 10{sup -3}mg/kg/day, and conducted an assessment to evaluate the public health significance of eating {sigma}DDT contaminated fish, accomplished by

  4. Modelling assessment of regional groundwater contamination due to historic smelter emissions of heavy metals

    NARCIS (Netherlands)

    Grift, B. van der; Griffioen, J.

    2008-01-01

    Historic emissions from ore smelters typically cause regional soil contamination. We developed a modelling approach to assess the impact of such contamination on groundwater and surface water load, coupling unsaturated zone leaching modelling with 3D groundwater transport modelling. Both historic an

  5. 33 CFR 203.61 - Emergency water supplies due to contaminated water source.

    Science.gov (United States)

    2010-07-01

    ... Water Act (see 40 CFR 141), is exceeded. (ii) The water supply has been identified as a source of... contaminated water source. 203.61 Section 203.61 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT... PROCEDURES Emergency Water Supplies: Contaminated Water Sources and Drought Assistance § 203.61...

  6. Effect of Air Stability on the Dispersal of Exhaled Contaminant in Rooms

    DEFF Research Database (Denmark)

    Xu, Chunwen; Gong, Guangcai; Nielsen, Peter V.

    2013-01-01

    Experiments are conducted in a full-scale chamber equipped with whole floor and whole ceiling supply or exhaust to form approximately zero and larger temperature gradients corresponding to unstable and stable air conditions. It can be observed that the air with smoke exhaled from a life-sized the......Experiments are conducted in a full-scale chamber equipped with whole floor and whole ceiling supply or exhaust to form approximately zero and larger temperature gradients corresponding to unstable and stable air conditions. It can be observed that the air with smoke exhaled from a life......-sized thermal manikin is locked and stratified at certain heights at stable condition while it mixes well with the ambient air and is diluted quickly through upper openings when the air is relatively unstable. The concentration of contaminant simulated by tracer gas (N2O) is measured both around and 0.35m from...... the manikin, indicating that the person who exhales the contaminant may not be polluted by himself as the protective effect of the thermal boundary layer around the body, especially in stable condition with two concentration zones and clean air drawn from the inlets. However, other persons facing...

  7. Ozone production by a dc corona discharge in air contaminated by n-heptane

    Science.gov (United States)

    Pekárek, S.

    2008-01-01

    Beneficial purposes of ozone such as elimination of odours, harmful bacteria and mildew can be used for transportation of food, fruits and vegetables with the aim to extend their storage life. To date the main technique used for this purpose in the transportation of these commodities, e.g. by trucks, was cooling. Here a combination of cooling together with the supply of ozone into containers with these commodities is considered. For these purposes we studied the effect of air contamination by n-heptane (part of automotive fuels) and humidity on ozone production by a dc hollow needle to mesh corona discharge. We found that, for both polarities of the needle electrode, addition of n-heptane to air (a) decreases ozone production; (b) causes discharge poisoning to occur at lower current than for air; (c) does not substantially influence the current for which the ozone production reaches the maximum. Finally the maximum ozone production for the discharge in air occurs for the same current as the maximum ozone production for the discharge contaminated by n-heptane. We also found that humidity decreases ozone production from air contaminated by n-heptane irrespective of the polarity of the coronating needle electrode. This dependence is stronger for the discharge with the needle biased positively.

  8. Ventilation as mitigation of PCB contaminated air in buildings

    DEFF Research Database (Denmark)

    Lyng, Nadja; Trap, Niels; Andersen, Helle Vibeke;

    2014-01-01

    The effect of ventilation on indoor concentrations was evaluated in 9 buildings constituting a total of 30 rooms. All cases had interior and/or exterior sealants containing PCB as primary source. Criteria for inclusion in the evaluation were that the indoor concentrations of PCBtotal In the remai......The effect of ventilation on indoor concentrations was evaluated in 9 buildings constituting a total of 30 rooms. All cases had interior and/or exterior sealants containing PCB as primary source. Criteria for inclusion in the evaluation were that the indoor concentrations of PCBtotal...... In the remaining four cases, the pressure difference between the room measured and the surroundings showed a tremendous effect on the concentration as opposed to the effect of ventilation. Pressure differences might affect the emission of PCB by motion of air through gaps and cracks along the PCB sealants. were...... measured in the same room at least twice and under different ventilation conditions. In general, PCB concentrations decrease with increased ventilation making the effect of ventilation to reduce human exposure feasible. In 26 case rooms, the mean reduction of the concentration was found to be 51% (median...

  9. Hazard Assessment of Chemical Air Contaminants Measured in Residences

    Energy Technology Data Exchange (ETDEWEB)

    Logue, J.M.; McKone, T.E.; Sherman, M. H.; Singer, B.C.

    2010-05-10

    Identifying air pollutants that pose a potential hazard indoors can facilitate exposure mitigation. In this study, we compiled summary results from 77 published studies reporting measurements of chemical pollutants in residences in the United States and in countries with similar lifestyles. These data were used to calculate representative mid-range and upper bound concentrations relevant to chronic exposures for 267 pollutants and representative peak concentrations relevant to acute exposures for 5 activity-associated pollutants. Representative concentrations are compared to available chronic and acute health standards for 97 pollutants. Fifteen pollutants appear to exceed chronic health standards in a large fraction of homes. Nine other pollutants are identified as potential chronic health hazards in a substantial minority of homes and an additional nine are identified as potential hazards in a very small percentage of homes. Nine pollutants are identified as priority hazards based on the robustness of measured concentration data and the fraction of residences that appear to be impacted: acetaldehyde; acrolein; benzene; 1,3-butadiene; 1,4-dichlorobenzene; formaldehyde; naphthalene; nitrogen dioxide; and PM{sub 2.5}. Activity-based emissions are shown to pose potential acute health hazards for PM{sub 2.5}, formaldehyde, CO, chloroform, and NO{sub 2}.

  10. Microlith-Based Catalytic Reactor for Air Quality and Trace Contaminant Control Applications

    Science.gov (United States)

    Vilekar, Saurabh; Hawley, Kyle; Junaedi, Christian; Crowder, Bruce; Prada, Julian; Mastanduno, Richard; Perry, Jay L.; Kayatin, Matthew J.

    2015-01-01

    Traditionally, gaseous compounds such as methane, carbon monoxide, and trace contaminants have posed challenges for maintaining clean air in enclosed spaces such as crewed spacecraft cabins as they are hazardous to humans and are often difficult to remove by conventional adsorption technology. Catalytic oxidizers have provided a reliable and robust means of disposing of even trace levels of these compounds by converting them into carbon dioxide and water. Precision Combustion, Inc. (PCI) and NASA - Marshall (MSFC) have been developing, characterizing, and optimizing high temperature catalytic oxidizers (HTCO) based on PCI's patented Microlith® technology to meet the requirements of future extended human spaceflight explorations. Current efforts have focused on integrating the HTCO unit with a compact, simple recuperative heat exchanger to reduce the overall system size and weight while also reducing its energy requirements. Previous efforts relied on external heat exchangers to recover the waste heat and recycle it to the oxidizer to minimize the system's power requirements; however, these units contribute weight and volume burdens to the overall system. They also result in excess heat loss due to the separation of the HTCO and the heat recuperator, resulting in lower overall efficiency. Improvements in the recuperative efficiency and close coupling of HTCO and heat recuperator lead to reductions in system energy requirements and startup time. Results from testing HTCO units integrated with heat recuperators at a variety of scales for cabin air quality control and heat melt compactor applications are reported and their benefits over previous iterations of the HTCO and heat recuperator assembly are quantified in this paper.

  11. Actual conditions of damage to agricultural and forestry products due to air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Eisei, K.

    1975-03-01

    The vigor and the sulfur content of leaves from several species of trees in the Tokyo area were investigated to assess the relationship between the two factors and to determine whether the leaf sulfur content indicates the degree of air pollution. The sulfur content of leaves of Pinus densiflora and Cryptomeria japonica, although showing age and seasonal differences, was greater in places where air pollution was higher, and the relationship was represented by a linear regression formula. The same tendency existed for Zelkova serrata. The content of water-soluble inorganic sulfur showed a closer relationship to air pollution, and in the peak season it amounted to 65% of the total leaf sulfur in polluted areas. Maximum sulfur values of leaves appeared to indicate the extent of damage due to air pollution.

  12. Negotiating indoor air-case report on negotiation of teachers' union, school board on air contaminants.

    Science.gov (United States)

    Gibson, Sarah; Levenstein, Charles

    2010-01-01

    School districts increasingly understand the need for an indoor air quality plan, but may have difficulty in producing a plan that all necessary parties will accept. This article provides a case study of how one Massachusetts school district, after experiencing environmental problems in an elementary school, worked with parents and unions to develop a comprehensive indoor air quality plan.

  13. Forced-air warming: a source of airborne contamination in the operating room?

    Directory of Open Access Journals (Sweden)

    David Leaper

    2009-12-01

    Full Text Available Forced-air-warming (FAW is an effective and widely used means for maintaining surgical normothermia, but FAW also has the potential to generate and mobilize airborne contamination in the operating room. We measured the emission of viable and non-viable forms of airborne contamination from an arbitrary selection of FAW blowers (n=25 in the operating room. A laser particle counter measured particulate concentrations of the air near the intake filter and in the distal hose airstream. Filtration efficiency was calculated as the reduction in particulate concentration in the distal hose airstream relative to that of the intake. Microbial colonization of the FAW blower’s internal hose surfaces was assessed by culturing the microorganisms recovered through swabbing (n=17 and rinsing (n=9 techniques. Particle counting revealed that 24% of FAW blowers were emitting significant levels of internally generated airborne contamination in the 0.5 to 5.0 mm size range, evidenced by a steep decrease in FAW blower filtration efficiency for particles 0.5 to 5.0 mm in size. The particle size-range-specific reduction in efficiency could not be explained by the filtration properties of the intake filter. Instead, the reduction was found to be caused by size-range-specific particle generation within the FAW blowers. Microorganisms were detected on the internal air path surfaces of 94% of FAW blowers. The design of FAW blowers was found to be questionable for preventing the build-up of internal contamination and the emission of airborne contamination into the operating room. Although we did not evaluate the link between FAW and surgical site infection rates, a significant percentage of FAW blowers with positive microbial cultures were emitting internally generated airborne contamination within the size range of free floating bacteria and fungi (<4 mm that could, conceivably, settle onto the surgical site.

  14. Identification of the source of PFOS and PFOA contamination at a military air base site.

    Science.gov (United States)

    Arias E, Victor A; Mallavarapu, Megharaj; Naidu, Ravi

    2015-01-01

    Although the use of perfluorooctane sulfonic acid (PFOS)/perfluorooctanoic acid (PFOA)-based aqueous fire-fighting foams (AFFF) has been banned due to their persistence, bioaccumulation and toxicity to biota, PFOS and PFOA are still present at significant levels in the environment due to their past usage. This study investigated the reasons for detection of PFOS and PFOA in an evaporation pond used to collect the wastewater arising from fire-fighting exercises at a military air base despite the replacement of PFOS/PFOA-based foam with no PFOS/PFOA-foam about 6 years ago. Concentrations in the wastewater stored in this pond ranged from 3.6 to 9.7 mg/L for PFOS and between 0.6 and 1.7 mg/L for PFOA. The hypothesis tested in a laboratory study was that PFOS and PFOA have accumulated in the sediments of the pond and can be released into the main body of the water. Concentrations detected in the sediments were 38 and 0.3 mg/g for PFOS and PFOA, respectively. These values exceed the recently reported average global values for sediments (0.2-3.8 ng/g for PFOS and from 0.1 to 0.6 ng/g for PFOA) by a factor of several thousands. PFOS and PFOA distribution coefficients were derived for the organic content of the pond sediment (1.6%). Identification of the source of contamination and knowledge of the partition between soil and aqueous phases are vital first steps in developing a sustainable remediation technology to remove the source from the site. This study clearly suggests that unless the sediment is cleaned of PFOS/PFOA, these chemicals will continue to be detected for a long period in the pond water, with potential adverse impacts on the ecosystem.

  15. Portable RF-Sensor System for the Monitoring of Air Pollution and Water Contamination

    Directory of Open Access Journals (Sweden)

    Joonhee Kang

    2012-01-01

    Full Text Available Monitoring air pollution including the contents of VOC, O3, NO2, and dusts has attracted a lot of interest in addition to the monitoring of water contamination because it affects directly to the quality of living conditions. Most of the current air pollution monitoring stations use the expensive and bulky instruments and are only installed in the very limited area. To bring the information of the air and water quality to the public in real time, it is important to construct portable monitoring systems and distribute them close to our everyday living places. In this work, we have constructed a low-cost portable RF sensor system by using 400 MHz transceiver to achieve this goal. Accuracy of the measurement was comparable to the ones used in the expensive and bulky commercial air pollution forecast systems.

  16. Storage of LWR spent fuel in air. Volume 3, Results from exposure of spent fuel to fluorine-contaminated air

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, M.E.; Thomas, L.E.

    1995-06-01

    The Behavior of Spent Fuel in Storage (BSFS) Project has conducted research to develop data on spent nuclear fuel (irradiated U0{sub 2}) that could be used to support design, licensing, and operation of dry storage installations. Test Series B conducted by the BSFS Project was designed as a long-term study of the oxidation of spent fuel exposed to air. It was discovered after the exposures were completed in September 1990 that the test specimens had been exposed to an atmosphere of bottled air contaminated with an unknown quantity of fluorine. This exposure resulted in the test specimens reacting with both the oxygen and the fluorine in the oven atmospheres. The apparent source of the fluorine was gamma radiation-induced chemical decomposition of the fluoro-elastomer gaskets used to seal the oven doors. This chemical decomposition apparently released hydrofluoric acid (HF) vapor into the oven atmospheres. Because the Test Series B specimens were exposed to a fluorine-contaminated oven atmosphere and reacted with the fluorine, it is recommended that the Test Series B data not be used to develop time-temperature limits for exposure of spent nuclear fuel to air. This report has been prepared to document Test Series B and present the collected data and observations.

  17. The risk of river pollution due to washout from contaminated floodplain water bodies during periods of high magnitude floods

    Science.gov (United States)

    Lyubimova, T.; Lepikhin, A.; Parshakova, Ya.; Tiunov, A.

    2016-03-01

    The risk of river pollution due to washout (removal of pollutants) from contaminated floodplain water bodies (floodplain lakes and quarries whose origin is related to the large-scale mining of nonmetallic building materials in the floodplain zone) during high magnitude flood periods is analyzed using a combination of one-, two- and three-dimensional hydrodynamic modeling and in situ measurements. The modeling performed for the floodplain water bodies contaminated by N compounds shows that during large magnitude floods washout occurs. The washout process consists of two stages: an initial rapid stage lasting about two hours during which the upper (3-4 m thick) layer is washed out, followed by a second stage when the concentration of NH4-N in the floodplain water body remains nearly constant. The maximum contaminant concentration in the river in the vicinity of a water intake for drinking water located 21 km downstream is attained about 9 h from the beginning of the flood; concentration of NH4-N can reach values several times larger than acceptable concentration guidelines. The initial primary peak in contaminant concentration at the water intake is followed by a slight decrease in contaminant concentration; a second peak related to the contaminant transport through the inundated floodplain subsequently occurs, after which the concentration slowly decreases, reaching acceptable values after 30-40 h. Contaminated floodplain water bodies located near drinking water supply systems are not significant sources of contamination during small and moderate floods, but during high magnitude floods, they can become sources of water pollution. Operational measures that can decrease potential health risks are discussed.

  18. Reactive Distillation and Air Stripping Processes for Water Recycling and Trace Contaminant Control

    Science.gov (United States)

    Boul, Peter J.; Lange, Kevin E.; Conger, Bruce; Anderson, Molly

    2009-01-01

    Reactive distillation designs are considered to reduce the presence of volatile organic compounds in the purified water. Reactive distillation integrates a reactor with a distillation column. A review of the literature in this field has revealed a variety of functional reactive columns in industry. Wastewater may be purified by a combination of a reactor and a distiller (e.g., the EWRS or VPCAR concepts) or, in principle, through a design which integrates the reactor with the distiller. A review of the literature in reactive distillation has identified some different designs in such combinations of reactor and distiller. An evaluation of reactive distillation and reactive air stripping is presented with regards to the reduction of volatile organic compounds in the contaminated water and air. Among the methods presented, an architecture is presented for the evaluation of the simultaneous oxidation of organics in air and water. These and other designs are presented in light of potential improvements in power consumptions and air and water purities for architectures which include catalytic activity integrated into the water processor. In particular, catalytic oxidation of organics may be useful as a tool to remove contaminants that more traditional distillation and/or air stripping columns may not remove. A review of the current leading edge at the commercial level and at the research frontier in catalytically active materials is presented. Themes and directions from the engineering developments in catalyst design are presented conceptually in light of developments in the nanoscale chemistry of a variety of catalyst materials.

  19. Measurements of air contaminants during the Cerro Grande fire at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Eberhart, Craig

    2010-08-01

    Ambient air sampling for radioactive air contaminants was continued throughout the Cerro Grande fire that burned part of Los Alamos National Laboratory. During the fire, samples were collected more frequently than normal because buildup of smoke particles on the filters was decreasing the air flow. Overall, actual sampling time was 96% of the total possible sampling time for the May 2000 samples. To evaluate potential human exposure to air contaminants, the samples were analyzed as soon as possible and for additional specific radionuclides. Analyses showed that the smoke from the fire included resuspended radon decay products that had been accumulating for many years on the vegetation and the forest floor that burned. Concentrations of plutonium, americium, and depleted uranium were also measurable, but at locations and concentrations comparable to non-fire periods. A continuous particulate matter sampler measured concentrations that exceeded the National Ambient Air Quality Standard for PM-10 (particles less than 10 micrometers in diameter). These high concentrations were caused by smoke from the fire when it was close to the sampler.

  20. (Environmental investigation of ground water contamination at Wright- Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This Health and Safety Plan (HSP) was developed for the Environmental Investigation of Ground-water Contamination Investigation at Wright-Patterson Air Force Base near Dayton, Ohio, based on the projected scope of work for the Phase 1, Task 4 Field Investigation. The HSP describes hazards that may be encountered during the investigation, assesses the hazards, and indicates what type of personal protective equipment is to be used for each task performed. The HSP also addresses the medical monitoring program, decontamination procedures, air monitoring, training, site control, accident prevention, and emergency response.

  1. Implications of OSHA's reliance on TLVs in developing the air contaminants standard

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, J.C.; Paxman, D.G.; Rappaport, S.M. (Univ. of California, Berkeley (USA))

    1991-01-01

    This paper evaluates the decision by the Occupational Safety and Health Administration (OSHA) to base its Air Contaminants Standard on the threshold limit values (TLVs) of the American Conference of Governmental Industrial Hygienists. Contrary to the claim made by OSHA in promulgating the standard, the TLV list was not the sole available basis for a generic standard covering toxic air contaminants. The National Institute for Occupational Safety and Health (NIOSH) presented data indicating that the TLVs were insufficiently protective for 98 substances. NIOSH Recommended Exposure Limits (RELs) were available for 59 of these substances. The ratio of PEL to REL ranged up to 1,000, with a median of 2.5 and a mean of 71.4. OSHA excluded 42 substances from the standard altogether despite the availability of NIOSH RELs, solely because no TLV had been established.

  2. Degradation of Nafion due to contamination from Swelling-Dehydration Cycles

    DEFF Research Database (Denmark)

    Andersen, Shuang Ma; Morgen, Per; Skou, Eivind Morten

    degradation in direct methanol fuel cells (DMFCs), where liquid water has direct contact with the electrolyte. An ex-situ experiment was established with swelling-dehydration cycles on the membrane. However, formation of sulfonic anhydride was not detected during the entire treatment; instead contamination...... from traces calcium in the nominally pure water used in the experiment was found to be the primary reason for the deterioration of the membrane properties. Trace impurities in the liquid methanol feed in DMFC may therefore represent an important contamination source....

  3. Numerical analysis of ALADIN optics contamination due to outgassing of solar array materials

    Energy Technology Data Exchange (ETDEWEB)

    Markelov, G [Advanced Operations and Engineering Services (AOES) Group BV, Postbus 342, 2300 AH Leiden (Netherlands); Endemann, M [ESA-ESTEC/EOP-PAS, Postbus 299, 2200 AG Noordwijk (Netherlands); Wernham, D [ESA-ESTEC/EOP-PAQ, Postbus 299, 2200 AG Noordwijk (Netherlands)], E-mail: Gennady.Markelov@aoes.com

    2008-03-01

    ALADIN is the very first space-based lidar that will provide global wind profile and a special attention has been paid to contamination of ALADIN optics. The paper presents a numerical approach, which is based on the direct simulation Monte Carlo method. The method allows one to accurately compute collisions between various species, in the case under consideration, free-stream flow and outgassing from solar array materials. The collisions create a contamination flux onto the optics despite there is no line-of-sight from the solar arrays to the optics. Comparison of obtained results with a simple analytical model prediction shows that the analytical model underpredicts mass fluxes.

  4. Distribution of Exhaled Contaminants and Personal Exposure in a Room using Three Different Air Distribution Strategies

    DEFF Research Database (Denmark)

    Olmedo, Inés; Nielsen, Peter V.; Adana, M. Ruiz de;

    2012-01-01

    . Human exhalation is studied in detail for different distribution systems: displacement and mixing ventilation as well as a system without mechanical ventilation. Two thermal manikins breathing through the mouth are used to simulate the exposure to human exhaled contaminants. The position and distance...... between the manikins are changed to study the influence on the level of exposure. The results show that the air exhaled by a manikin flows a longer distance with a higher concentration in case of displacement ventilation than in the other two cases, indicating a significant exposure to the contaminants...... for one person positioned in front of another. However, in all three cases, the exhalation flow of the source penetrates the thermal plume, causing an increase in the concentration of contaminants in front of the target person. The results are significantly dependent on the distance and position between...

  5. Time-lapse electrical resistivity anomalies due to contaminant transport around landfills

    Directory of Open Access Journals (Sweden)

    J. Yang

    2007-06-01

    Full Text Available The extent of landfill leachate can be delineated by geo-electrical imaging as a response to the varying electrical resistivity in the contaminated area. This research was based on a combination of hydrogeological numerical simulation followed by geophysical forward and inversion modeling performed to evaluate the migration of a contaminant plume from a landfill. As a first step, groundwater flow and contaminant transport was simulated using the finite elements numerical modeling software FEFLOW. The extent of the contaminant plume was acquired through a hydrogeological model depicting the distributions of leachate concentration in the system. Next, based on the empirical relationship between the concentration and electrical conductivity of the leachate in the porous media, the corresponding geo-electrical structure was derived from the hydrogeological model. Finally, forward and inversion computations of geo-electrical anomalies were performed using the finite difference numerical modeling software DCIP2D/DCIP3D. The image obtained by geophysical inversion of the electric data was expected to be consistent with the initial hydrogeological model, as described by the distribution of leachate concentration. Numerical case studies were conducted for various geological conditions, hydraulic parameters and electrode arrays, from which conclusions were drawn regarding the suitability of the methodology to assess simple to more complex geo-electrical models. Thus, optimal mapping and monitoring configurations were determined.

  6. Degradation and contamination of perfluorinated sulfonic acid membrane due to swelling-dehydration cycles

    DEFF Research Database (Denmark)

    Andersen, Shuang Ma; Morgen, Per; Skou, Eivind Morten

    to the membrane degradation in direct methanol fuel cells (DMFCs), where liquid water has direct contact with the electrolyte. An ex-situ experiment was established with swelling-dehydration cycles on the membrane. However, formation of sulfonic anhydride was not detected during the entire treatment; instead...... contamination from calcium was found the primary reason for the deterioration of the membrane properties....

  7. [Fire disaster due to deflagration of a propane gas-air mixture].

    Science.gov (United States)

    Nadjem, Hadi; Vogt, Susanne; Simon, Karl-Heinz; Pollak, Stefan; Geisenberger, Dorothee; Kramer, Lena; Pircher, Rebecca; Perdekampl, Markus Große; Thierauf-Emberger, Annette

    2015-01-01

    On 26 Nov 2012, a serious fire occurred at Neustadt/Black Forest in which 14 persons in a sheltered workshop died and 10 other individuals were injured. The fire was caused by the unbridled escape of propane gas due to accidental disconnection of the screw fixing between a gas bottle and a catalytic heater. Deflagration of the propane gas-air mixture set the workshop facilities on fire. In spite of partly extensive burns the fatally injured victims could be rapidly identified. The results of the fire investigations at the scene and the autopsy findings are presented. Carboxyhemoglobin concentrations ranged between 8 and 56 % and signs of fire fume inhalation were present in all cases. Three victims had eardrum ruptures due to the sudden increase in air pressure during the deflagration.

  8. Well site conditions associated with nitrate contamination in a multilayer semiconfined aquifer of Buenos Aires, Argentina

    Science.gov (United States)

    Carbó, L. I.; Flores, M. C.; Herrero, M. A.

    2009-06-01

    A stepwise logistic regression (LR) model was generated to evaluate the association between contamination of groundwater by nitrates with several risk factors such as soil types, farm facilities and practises, and well characteristics. The odds ratio was calculated to estimate the degree of impact that the associated variables had on the risk of contamination in a semiconfined multilayer aquifer underlying rural areas of Buenos Aires, Argentina. Duplicate farm groundwater samples ( n = 160) were taken and nitrate was analyzed. Data, involving various farm factors, was gathered via two questionnaires concerning farm’s general and productive aspects, and well characteristics. Statistical tests were run between nitrates and each variable present in the survey. A 96.25% of the samples presented detectable nitrate levels, 40.91% of which had more than 45 ppm nitrates. The final LR model involved five of the variables under study: well age, soil permeability, depth of water table, location, and distance from well to contamination sources. Cross validation proved to be a good estimator of nitrate water contamination. Suspicions about how these characteristics influence groundwater contamination by nitrates were confirmed, and as these five factors represent a higher risk for this type of aquifer, their proper management may contribute to a better resource protection.

  9. Effects of contaminants on reproductive success of aquatic birds nesting at Edwards Air Force Base, California

    Science.gov (United States)

    Hothem, R.L.; Crayon, J.J.; Law, M.A.

    2006-01-01

    Contamination by organochlorine pesticides (OCs), polychlorinated biphenyls, metals, and trace elements at Edwards Air Force Base (EAFB), located in the Mojave Desert, could adversely affect nesting aquatic birds, especially at the sewage lagoons that comprise Piute Ponds. Estimates of avian reproduction, in conjunction with analyses of eggs and avian foods for contaminant residues, may indicate the potential for negative effects on avian populations. From 1996 to 1999, we conducted studies at the Piute Ponds area of EAFB to evaluate the impacts of contaminants on nesting birds. Avian reproduction was evaluated in 1999. Eggs were collected for chemical analyses in 1996 and 1999, and African clawed frogs (Xenopus laevis), a likely food source, were collected for chemical analyses in 1998. Avian species occupying the higher trophic levels-black-crowned night-heron (Nycticorax nycticorax), white-faced ibis (Plegadis chihi), and American avocet (Recurvirostra americana)-generally bioaccumulated higher concentrations of contaminants in their eggs. Reproductive success and egg hatchability of night-herons and white-faced ibises in the Piute Ponds were similar to results observed at other western colonies. Deformities were observed in only one embryo in this study, but concentrations of contaminants evaluated in this ibis embryo were considered insufficient to have caused the deformities. Because clawed frogs, a primary prey item for night-herons at Piute Ponds, had no detectable levels of any OCs, it is likely that OCs found in night-heron eggs were acquired from the wintering grounds rather than from EAFB. The presence of isomers of dichlorodiphenyltrichloroethane (DDT) in ibis eggs indicated recent exposure, but invertebrates used for food by ibises were not sampled at Piute Ponds, and conclusions about the source of OCs in ibis eggs could not be made. Concentrations of contaminants in random and failed eggs of individual species were not different, and we concluded

  10. Contamination due to memory effects in filtered vacuum arc plasma deposition systems

    CERN Document Server

    Martins, D R; Verdonck, P; Brown, I G

    2002-01-01

    Thin film synthesis by filtered vacuum arc plasma deposition is a widely used technique with a number of important emerging technological applications. A characteristic feature of the method is that during the deposition process not only is the substrate coated by the plasma, but the plasma gun itself and the magnetic field coil and/or vacuum vessel section constituting the macroparticle filter are also coated to some extent. If then the plasma gun cathode is changed to a new element, there can be a contamination of the subsequent film deposition by sputtering from various parts of the system of the previous coating species. We have experimentally explored this effect and compared our results with theoretical estimates of sputtering from the SRIM (Stopping and Range of Ions in Matter) code. We find film contamination of order 10-4 - 10-3, and the memory of the prior history of the deposition hardware can be relatively long-lasting.

  11. Performance of personalized ventilation combined with chilled ceiling in an office room: inhaled air quality and contaminant distribution

    DEFF Research Database (Denmark)

    Lipczynska, Aleksandra; Kaczmarczyk, Jan; Melikov, Arsen Krikor

    2014-01-01

    In a simulated two persons’ office room inhaled air quality and contaminant distribution provided with personalized ventilation combined with chilled ceiling, mixing ventilation only, chilled ceiling with mixing ventilation and chilled ceiling with mixing and personalized ventilation was studied...

  12. Bioremediation of contaminated marine sediments can enhance metal mobility due to changes of bacterial diversity.

    Science.gov (United States)

    Fonti, Viviana; Beolchini, Francesca; Rocchetti, Laura; Dell'Anno, Antonio

    2015-01-01

    Bioremediation strategies applied to contaminated marine sediments can induce important changes in the mobility and bioavailability of metals with potential detrimental consequences on ecosystem health. In this study we investigated changes of bacterial abundance and diversity (by a combination of molecular fingerprinting and next generation sequencing analyses) during biostimulation experiments carried out on anoxic marine sediments characterized by high metal content. We provide evidence that the addition of organic (lactose and/or acetate) and/or inorganic compounds to contaminated sediments determines a significant increase of bacterial growth coupled with changes in bacterial diversity and assemblage composition. Experimental systems supplied only with organic substrates were characterized by an increase of the relative importance of sulfate reducing bacteria belonging to the families Desulfobacteraceae and Desulfobulbaceae with a concomitant decrease of taxa affiliated with Flavobacteriaceae. An opposite effect was observed in the experimental treatments supplied also with inorganic nutrients. The increase of bacterial metabolism coupled with the increase of bacterial taxa affiliated with Flavobacteriaceae were reflected in a significant decrease of Cd and Zn associated with sedimentary organic matter and Pb and As associated with the residual fraction of the sediment. However, independently from the experimental conditions investigated no dissolution of metals occurred, suggesting a role of bacterial assemblages in controlling metal solubilization processes. Overall results of this study have allowed to identify key biogeochemical interactions influencing the metal behavior and provide new insights for a better understanding of the potential consequences of bio-treatments on the metal fate in contaminated marine sediments.

  13. Monitoring contamination due to materials outgassing by QCM-based sensors

    Science.gov (United States)

    Dirri, Fabrizio

    2016-07-01

    F. Dirri, E. Palomba, A. Longobardo, D. Biondi, A. Boccaccini, E. Zampetti, B. Saggin, D. Scaccabarozzi, A. Tortora, A. Nanni, J. Alves, A. Tighe Outgassing from spacecraft materials often occurs and degassing contaminants can degrade critical spacecraft surfaces, such as optical systems, solar panels, thermal radiators and thermal management systems. The main contaminants are the water adsorbed by cold surface, organics from spacecraft structure, electronics, insulation and thrusters firings [1]. Thus, it is fundamental to monitor these low-outgassing rates especially in a long duration mission: Quartz Crystal Microbalance (QCM) based sensors (i.e. single and double crystal configurations) are a suitable instruments to monitor step by step these degradation processes which occur in space conditions. The Contamination Assessment Microbalance (CAM) is a device aimed at monitoring in-orbit contamination of sensitive surfaces and payloads on ESA's future satellites. The device, developed by a consortium of Italian research Institutes, is based on QCM technology, previously considered by NASA and ESA experiments performed on Space Shuttle and satellite missions [2,3,4]. CAM is a low mass (200 grams for the sensor head), low volume (smaller than 5x5x5 cm3 for the sensor head) and low power consumption (less than 1.5 W) sensor. The device is composed by: 1) the Sensor Head, containing a sensing crystal (which measures the deposited contaminant mass), a reference crystal (used as frequency reference), their related Proximity Electronics (PE) and a Temperature Control System (TCS); 2) the Main Electronics Unit (MEU), which acquires the signal in output from Sensor Head unit; 3) the Harness connecting Sensor Head and MEU; 4) the User Interface (UI) to read and display the data. The device shows several improvements, i.e. possibility to measure directly the crystal temperature (with an accuracy better than 0.1°C), large measurable mass range (from 5•10-9 to 7•10-4 g/cm2

  14. Measurement of airborne 131I, 134Cs, and 137Cs nuclides due to the Fukushima reactors accident in air particulate in Milan (Italy)

    CERN Document Server

    Clemenza, Massimiliano; Previtali, Ezio; Sala, Elena

    2011-01-01

    After the earthquake and the tsunami occurred in Japan on 11th March 2011, four of the Fukushima reactors had released in air a large amount of radioactive isotopes that had been diffused all over the world. The presence of airborne 131I, 134Cs, and 137Cs in air particulate due to this accident has been detected and measured in the Low Radioactivity Laboratory operating in the Department of Environmental Sciences of the University of Milano-Bicocca. The sensitivity of the detecting apparatus is of 0.2 \\mu Bq/m3 of air. Concentration and time distribution of these radionuclides were determined and some correlations with the original reactor releases were found. Radioactive contaminations ranging from a few to 400 \\mu Bq/m3 for the 131I and of a few tens of \\mu Bq/m3 for the 137Cs and 134Cs have been detected

  15. Numerical Assessment of Indoor Air Exposure Risk from Subsurface NAPL Contamination under Hydrologic Uncertainties

    Science.gov (United States)

    Unger, A.; Yu, S.

    2007-12-01

    Understanding the risk of indoor air exposure to residual contaminants in the subsurface following the redevelopment of contaminated land redevelopment project is a central issue at many brownfield sites. In this study, we examine various mechanisms controlling vapor phase intrusion into the indoor air of a typical residential dwelling from a NAPL source located below the water table, and consequently assess the indoor air exposure risk under multiple hydrologic uncertainties. For this purpose, a multi-phase multi-component numerical model, CompFlow Bio is used to simulate the evolution of a TCE source zone and dissolved plume in a variably saturated heterogeneous aquifer, along with the transport of dissolved TCE upwards through the capillary fringe with subsequent migration of TCE vapors in the vadose zone subject to barometric pressure fluctuations. The TCE vapors then enter the basement of the residential dwelling through a crack in the foundation slab, driven by a slight vacuum within the basement relative to the ambient atmosphere as well as the barometric pressure fluctuations. Hydrologic uncertainties affecting the indoor air concentration of TCE include the vacuum in the basement, the aperture of the crack in the foundation slab, the heterogeneous permeability field, the thickness of the capillary fringe, barometric fluctuations, recharge rates and the location of the TCE source zone. CompFlow Bio is then used to determine the future concentration of TCE into the basement as a consequence of imperfect knowledge in the various hydrologic parameters, and to evaluate the effectiveness of alternative remedial and foundation design options to minimize the exposure risk to the indoor air conditional upon the available data collected at the site. The outcome of this approach is two-fold. First, the owner of the site can reasonably evaluate the future indoor air exposure risk following the redevelopment of a formerly contaminated site following remediation

  16. Remediation of arsenic contaminated soil by coupling oxalate washing with subsequent ZVI/Air treatment.

    Science.gov (United States)

    Cao, Menghua; Ye, Yuanyao; Chen, Jing; Lu, Xiaohua

    2016-02-01

    The application of a novel coupled process with oxalate washing and subsequent zero-valent iron (ZVI)/Air treatment for remediation of arsenic contaminated soil was investigated in the present study. Oxalate is biodegradable and widely present in the environment. With addition of 0.1 mol L(-1) oxalate under circumneutral condition, 83.7% and 52.6% of arsenic could be removed from a spiked kaolin and an actual contaminated soil respectively. Much more oxalate adsorption on the actual soil was attributed to the higher soil organic matter and clay content. Interestingly, oxalate retained in the washing effluent could act as an organic ligand to promote the oxidation efficiency of ZVI/Air at near neutral pH. Compared with the absence of oxalate, much more As(III) was oxidized. Arsenic was effectively adsorbed on iron (hydr)oxides as the consumption of oxalate and the increase of pH value. For the actual soil washing effluent, about 94.9% of total arsenic was removed after 120 min's treatment without pH adjustment. It has been demonstrated that As(V) was the dominant arsenic speciation adsorbed on iron (hydr)oxides. This study provides a promising alternative for remediation of arsenic contaminated soil in view of its low cost and environmental benign.

  17. Effect of negative air ions on the potential for bacterial contamination of plastic medical equipment

    Directory of Open Access Journals (Sweden)

    Kerr Kevin G

    2010-04-01

    acrylonitrile, did however develop a positive charge in the presence of the ionizer. Conclusion The findings of the study suggest that the action of negative air ionizers significantly alters the electrostatic landscape of the clinical environment, and that this has the potential to cause any Acinetobacter-bearing particles in the air to be strongly repelled from some plastic surfaces and attracted to others. In so doing, this may prevent critical items of equipment from becoming contaminated with the bacterium.

  18. Long-term consequences of arsenic poisoning during infancy due to contaminated milk powder

    Science.gov (United States)

    Dakeishi, Miwako; Murata, Katsuyuki; Grandjean, Philippe

    2006-01-01

    Arsenic toxicity is a global health problem affecting many millions of people. The main source of exposure is drinking water contaminated by natural geological sources. Current risk assessment is based on the recognized carcinogenicity of arsenic, but neurotoxic risks have been overlooked. In 1955, an outbreak of arsenic poisoning occurred among Japanese infants, with more than 100 deaths. The source was contaminated milk powder produced by the Morinaga company. Detailed accounts of the Morinaga dried milk poisoning were published in Japanese only, and an overview of this poisoning incident and its long-term consequences is therefore presented. From analyses available, the arsenic concentration in milk made from the Morinaga milk powder is calculated to be about 4–7 mg/L, corresponding to daily doses slightly above 500 μg/kg body weight. Lower exposures would result from using diluted milk. Clinical poisoning cases occurred after a few weeks of exposure, with a total dose of about 60 mg. This experience provides clear-cut evidence for hazard assessment of the developmental neurotoxicity. At the present time, more than 600 surviving victims, now in their 50s, have been reported to suffer from severe sequelae, such as mental retardation, neurological diseases, and other disabilities. Along with more recent epidemiological studies of children with environmental arsenic exposures, the data amply demonstrate the need to consider neurotoxicity as a key concern in risk assessment of inorganic arsenic exposure. PMID:17076881

  19. Long-term consequences of arsenic poisoning during infancy due to contaminated milk powder

    Directory of Open Access Journals (Sweden)

    Grandjean Philippe

    2006-10-01

    Full Text Available Abstract Arsenic toxicity is a global health problem affecting many millions of people. The main source of exposure is drinking water contaminated by natural geological sources. Current risk assessment is based on the recognized carcinogenicity of arsenic, but neurotoxic risks have been overlooked. In 1955, an outbreak of arsenic poisoning occurred among Japanese infants, with more than 100 deaths. The source was contaminated milk powder produced by the Morinaga company. Detailed accounts of the Morinaga dried milk poisoning were published in Japanese only, and an overview of this poisoning incident and its long-term consequences is therefore presented. From analyses available, the arsenic concentration in milk made from the Morinaga milk powder is calculated to be about 4–7 mg/L, corresponding to daily doses slightly above 500 μg/kg body weight. Lower exposures would result from using diluted milk. Clinical poisoning cases occurred after a few weeks of exposure, with a total dose of about 60 mg. This experience provides clear-cut evidence for hazard assessment of the developmental neurotoxicity. At the present time, more than 600 surviving victims, now in their 50s, have been reported to suffer from severe sequelae, such as mental retardation, neurological diseases, and other disabilities. Along with more recent epidemiological studies of children with environmental arsenic exposures, the data amply demonstrate the need to consider neurotoxicity as a key concern in risk assessment of inorganic arsenic exposure.

  20. Wood anatomical changes due to uptake of cadmium and lead from contaminated soils in Acer velutinum seedlings

    Institute of Scientific and Technical Information of China (English)

    Zeynab Shahpoori; Vilma Bayramzadeh; Vahid Reza Safdari; Manoochehr Khan Zarinkafsh; Pedram Attarod; Roghayeh Jirroodnejad

    2012-01-01

    We investigated wood anatomical changes due to uptake and accumulation of cadmium and lead from contaminated soils in Acer velutinum Boiss seedlings.Two-year old seedlings were exposed for 180 days to soil concentrations with varying cadmium and lead concentrations.We measured three wood anatomical traits,average vessel area (μm2),vessel number per square millimetre,and vessel lumen area percentage (%).For assessing the cadmium and lead accumulation,we measured the concentrations in the soil,leaf,stem,and root.Average vessel area and vessel lumen area percentage were similar (p>0.05) in control and treated seedlings.Vessel number per square millimetre showed a decreasing trend from pith to bark in control and treated seedlings,and the trend was more pronounced in treated seedlings.We conclude that vessel number per square millimetre in A.velutinum is influenced by soil contamination.A.velutinum Boiss is not a suitable species for remediation of soils contaminated by cadmium and lead but it can be used as an indicator of the soil lead contamination,because lead concentrations in seedlings increased with increasing amount of lead in the soil.

  1. Human health risk due to consumption of vegetables contaminated with carcinogenic polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Sardar [Chinese Academy of Sciences, Xiamen (China). Inst. of Urban Environment; Peshawar Univ. (Pakistan). Dept. of Environmental Science; Cao, Qing [Chinese Academy of Sciences, Beijing (China). Research Center for Eco-Environemntal Sciences

    2012-02-15

    Polycyclic aromatic hydrocarbons (PAH) are persistent, toxic, and carcinogenic contaminants present in soil ecosystem globally. These pollutants are gradually accumulating in wastewater-irrigated soils and lead to the contamination of vegetables. Food chain contamination with PAH is considered as one of the major pathways for human exposure. This study was aimed to investigate the concentrations of PAH in soils and vegetables collected from wastewater-irrigated fields from metropolitan areas of Beijing, China. Origin of PAH, daily intake, and health risks of PAH through consumption of contaminated vegetables were studied. Soil samples were collected from the upper horizon (0-20 cm) of both wastewater-irrigated and reference sites and sieved (<2 mm mesh) and then followed by freeze-drying at -50 C and 123 {+-} 2 Pa. Standing vegetables were also collected from the same sites used for soil sampling and divided into roots and shoots, thoroughly washed with deionized water, and freeze-dried. PAH were extracted using the Soxhlet method with 200 mL DCM for 24 h, and the extracts were cleaned with silica adsorption chromatography prepared with silica gel, alumina, and capped with anhydrous sodium. The final concentrated extracts (soil and vegetable) were analyzed using gas chromatography-mass spectrometry (Agilent 6890). Bioaccumulation factors, daily intake of PAH, and carcinogenicity of PAH were calculated by different statistical equations. Results indicate that the soils and grown vegetables were contaminated with all possible carcinogenic PAH (declared by USEPA 2002) except indeno[1,2,3-c,d]pyrene. The highest concentration (242.9 {mu}g kg{sup -1}) was found for benzo(k)fluoranthene (BkF), while lowest (79.12 {mu}g kg{sup -1}) for benzo[a]pyrene (BaP). The emission sources of PAH were both pyrogenic and petrogenic in nature. However, the total concentrations of PAH were lower than the permissible limits set by different countries like Canada, Denmark and Germany

  2. Indoor Air Contaminant Adsorption By Palm Shell Activated Carbon Filter – A Proposed Study

    Directory of Open Access Journals (Sweden)

    Leman A.M

    2016-01-01

    Full Text Available Indoor air contaminant is a public issue. High Volatile Organic Compound (VOC, Carbon monoxide (CO, Carbon dioxide (CO2, and particulate matter is becoming main issue that needs to solve. Therefore, this study focus on improving indoor air quality by using activated carbon (AC for Ventilation and Air-Conditioning (VAC. It investigated because AC is widely explored but developing AC as a filter for VAC is not developed yet. The AC prepared by physical and chemical activation process and combination both of process and it was activated by H3PO4 and NaOH. Characterization and analysis process are consists of water content, ash content, bulk density, adsorption capacity, iodine number and indoor air filtering analysis. Treated activated carbon potential in achieving higher surface area of the structure to the range of 950 to 1150 m2/g for gas phase application. The higher surface area will adsorb more air pollution. Maintained properties of activated carbon such as hardness, density, pore, extractable ash, particle size (12 by 40 mesh and pH are becoming the main concern in achieving high quality of activated carbon.

  3. Global premature mortality due to anthropogenic outdoor air pollution and the contribution of past climate change

    Science.gov (United States)

    Silva, Raquel A.; West, J. Jason; Zhang, Yuqiang; Anenberg, Susan C.; Lamarque, Jean-François; Shindell, Drew T.; Collins, William J.; Dalsoren, Stig; Faluvegi, Greg; Folberth, Gerd; Horowitz, Larry W.; Nagashima, Tatsuya; Naik, Vaishali; Rumbold, Steven; Skeie, Ragnhild; Sudo, Kengo; Takemura, Toshihiko; Bergmann, Daniel; Cameron-Smith, Philip; Cionni, Irene; Doherty, Ruth M.; Eyring, Veronika; Josse, Beatrice; MacKenzie, I. A.; Plummer, David; Righi, Mattia; Stevenson, David S.; Strode, Sarah; Szopa, Sophie; Zeng, Guang

    2013-09-01

    Increased concentrations of ozone and fine particulate matter (PM2.5) since preindustrial times reflect increased emissions, but also contributions of past climate change. Here we use modeled concentrations from an ensemble of chemistry-climate models to estimate the global burden of anthropogenic outdoor air pollution on present-day premature human mortality, and the component of that burden attributable to past climate change. Using simulated concentrations for 2000 and 1850 and concentration-response functions (CRFs), we estimate that, at present, 470 000 (95% confidence interval, 140 000 to 900 000) premature respiratory deaths are associated globally and annually with anthropogenic ozone, and 2.1 (1.3 to 3.0) million deaths with anthropogenic PM2.5-related cardiopulmonary diseases (93%) and lung cancer (7%). These estimates are smaller than ones from previous studies because we use modeled 1850 air pollution rather than a counterfactual low concentration, and because of different emissions. Uncertainty in CRFs contributes more to overall uncertainty than the spread of model results. Mortality attributed to the effects of past climate change on air quality is considerably smaller than the global burden: 1500 (-20 000 to 27 000) deaths yr-1 due to ozone and 2200 (-350 000 to 140 000) due to PM2.5. The small multi-model means are coincidental, as there are larger ranges of results for individual models, reflected in the large uncertainties, with some models suggesting that past climate change has reduced air pollution mortality.

  4. Hospital ventilation standards and energy conservation: chemical contamination of hospital air. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rainer, D.; Michaelsen, G.S.

    1980-03-01

    In an era of increasing energy conservation consciousness, a critical reassessment of the validity of hospital ventilation and thermal standards is made. If current standards are found to be excessively conservative, major energy conservation measures could be undertaken by rebalancing and/or modification of current HVAC systems. To establish whether or not reducing ventilation rates would increase airborne chemical contamination to unacceptable levels, a field survey was conducted to develop an inventory and dosage estimates of hospital generated airborne chemical contaminants to which patients, staff, and visitors are exposed. The results of the study are presented. Emphasis is on patient exposure, but an examination of occupational exposure was also made. An in-depth assessment of the laboratory air environment is documented. Housekeeping products used in survey hospitals, hazardous properties of housekeeping chemicals and probable product composition are discussed in the appendices.

  5. Outbreak of infection in a burns unit due to Pseudomonas aeruginosa originating from contaminated tubing used for irrigation of patients

    DEFF Research Database (Denmark)

    Kolmos, H J; Thuesen, B; Nielsen, S V;

    1993-01-01

    Five patients with extensive deep burns developed septicaemia due to Pseudomonas aeruginosa serogroup O-7.8 and phage type 21 or 21/188 shortly after they had been admitted to hospital. Four other burned patients became colonized with the same strain. The source of infection was contaminated tap...... water used for irrigation of the burns, as part of the first-aid treatment which the patients received when entering the hospital. Contamination was restricted to showers and tubing that were permanently connected to the taps, and the outbreak stopped after they had been disinfected. Tubing and showers...... used for irrigation of burns should be dismantled and heat-disinfected after each patient and not reconnected to the taps until immediately before the next treatment. Taps used for irrigation of burns should be monitored regularly for the presence of P. aeruginosa and other potentially pathogenic...

  6. [Role of environment in complex diseases: air pollution and food contaminants].

    Science.gov (United States)

    Scheen, A J; Giet, D

    2012-01-01

    Our polluted environment exposes human beings, along their life, to various toxic compounds that could trigger and aggravate different complex diseases. Such a phenomenon is well recognized for cardiovascular diseases, respiratory diseases and cancers, but other chronic inflammatory disorders may also been implicated. The most common factors, but also the most toxic, and thereby the most extensively investigated, are air pollutants (both indoor and outdoor pollution) and various contaminants present in drinking water and food (organic compounds, chemical products, heavy metals, ...). The complex interrelationships between food and pollutants, on the one hand, and between gene and environmental pollutants, including the influence of epigenetics, on the other hand, deserve further careful studies.

  7. The Use of Numerical Modeling to Address Surface and Subsurface Water Contamination due to Fracwater Spills in Larry's Creek, Pennsylvania

    Science.gov (United States)

    Simon, C. A.; Arjmand, S.; Abad, J. D.

    2012-12-01

    Because of its relatively low carbon dioxide emissions, natural gas is considered to be more efficient and environmentally friendly than other non-renewable fuels. As a result of this, among other factors, in recent years natural gas has become one of the world's primary energy sources. In the United States, drilling to extract natural gas has substantially increased over the past few years. In the Marcellus Shale, unconventional gas is currently extracted by using two new techniques: horizontal drilling and hydraulic fracturing. Today, fracking fluids which have been applied as part of the hydraulic fracturing process to fracture the shale rock and release the gas, pose a major environmental concern. These fluids are highly contaminated with radionuclides and toxic metals and any exposure of this highly polluted water to surface water or soil could heavily contaminate the media. The area selected for the current study is the Larry's Creek, located in Lycoming County in Pennsylvania. Larry's Creek Watershed was adversely affected by coal and iron mines activities in the 19th century. Though, the water quality in this creek was considered to be good as of 2006. Recently, oil and gas drilling activities have raised concerns about the creek's water quality again. A major environmental hazard is the freshwater contamination by frac/flowback water. Drilling companies are using impoundments on site to keep fracwater, and to store and evaporate flowback water. However, these ponds may fail or leak due to construction problems and/or accidents. Close to Saladasburg, Larry's Creek's stream was observed running rich with clay in October 19, 2011. Historical measurements show very high turbidity during this period which has raised questions about water contamination by the gas industry activities in the upper stream of the watershed. An interstate watershed agency has reported spills in Wolf Run in different drilling sites in the Larry's Creek basin. The focus of this study

  8. Dynamic analysis of a BLDC motor with mechanical and electromagnetic interaction due to air gap variation

    Science.gov (United States)

    Im, Hyungbin; Yoo, Hong Hee; Chung, Jintai

    2011-04-01

    In this study, the dynamic behaviors of a BLDC motor are analyzed, when the motor undergoes mechanical and electromagnetic interaction due to an air gap variation between the stator and rotor. When considering the air gap variation caused by the translational motion of the rotor relative to the stator, the kinetic and potential energies, Rayleigh dissipation function, and the magnetic coenergy are expressed in terms of the rotor displacements and stator currents. With these energies and function, new equations of motion are derived using Lagrange's equation. The equations for the proposed model are nonlinear equations in which the displacements and currents are coupled. The time responses for the displacements and currents are computed for the proposed and previous models. Furthermore, the effects of rotor eccentricity are also investigated. It is found that, when the air gap varies with time, the time responses for the proposed and previous models have small differences in the stator currents, electromagnetic torques, and rotating speeds. However, the time responses have large differences in the rotor displacements. Therefore, this paper claims that the proposed model describes the dynamic behaviors of the motor more accurately than the previous model. It is also shown that rotor eccentricity increases the stator current period and the electromagnetic torque, while it decreases the rotating speed of the rotor.

  9. Historical arsenic contamination of soil due to long-term phosphate fertiliser applications.

    Science.gov (United States)

    Hartley, Tom N; Macdonald, Andy J; McGrath, Steve P; Zhao, Fang-Jie

    2013-09-01

    Archived samples from the Park Grass Experiment, established in 1856, were analysed to determine the impacts of long-term phosphate fertiliser applications on arsenic concentrations in soil and herbage. In plots receiving 35 kg P ha(-1) annually (+P), topsoil As concentrations almost doubled from an initial value of ∼10 mg kg(-1) during 1888-1947 and remained stable thereafter. The phosphate fertilisers used before 1948 contained 401-1575 mg As kg(-1), compared to 1.6-20.3 mg As kg(-1) in the later samples. Herbage samples from the +P plots collected during 1888-1947 contained significantly more As than those from the -P plots, but later samples did not differ significantly. Mass-balance calculations show that the increase in soil As can be explained by the As input from P fertiliser applications before 1948. The results demonstrate that the P fertilisers used on the Park Grass Experiment before 1948 caused substantial As contamination of the soil.

  10. Nosocomial transmission of Serratia marcescens in a veterinary hospital due to contamination by benzalkonium chloride.

    Science.gov (United States)

    Fox, J G; Beaucage, C M; Folta, C A; Thornton, G W

    1981-01-01

    During a 1-year period, Serratia marcescens was isolated from 50% of all contaminate intravenous catheters from dogs and cats in a large veterinary hospital. S. marcescens was also isolated from respiratory tracts, genitourinary tracts, skin, and other sites in hospitalized animals. A total of 55% of the clinical isolates and 66% of the intravenous catheter isolates had the same API biochemical profile. The source of the S. marcescens was determined to be aqueous benzalkonium chloride (0.025%) sponge pots located in the intensive care unit, surgery rooms, and outpatient clinic areas of the hospital. Of the 11 S. marcescens isolates submitted to the Centers for Disease Control for serotyping (6 from aqueous benzalkonium chloride sponge pots, 5 from intravenous catheters), 8 were identified as serotype O10:H11. All S. marcescens isolates tested for antibiotic susceptibilities were multiply resistant; isolates were most frequently resistant to streptomycin, cephalothin, and ampicillin. This study demonstrates that improper use of disinfectants plays an important role in the nosocomial transmission of S. marcescens. PMID:7024303

  11. Uptake of toluene and ethylbenzene by plants: removal of volatile indoor air contaminants.

    Science.gov (United States)

    Sriprapat, Wararat; Suksabye, Parinda; Areephak, Sirintip; Klantup, Polawat; Waraha, Atcharaphan; Sawattan, Anuchit; Thiravetyan, Paitip

    2014-04-01

    Air borne uptake of toluene and ethylbenzene by twelve plant species was examined. Of the twelve plant species examined, the highest toluene removal was found in Sansevieria trifasciata, while the ethylbenzene removal from air was with Chlorophytum comosum. Toluene and ethylbenzene can penetrate the plant׳s cuticle. However, the removal rates do not appear to be correlated with numbers of stomata per plant. It was found that wax of S. trifasciata and Sansevieria hyacinthoides had greater absorption of toluene and ethylbenzene, and it contained high hexadecanoic acid. Hexadecanoic acid might be involved in toluene and ethylbenzene adsorption by cuticles wax of plants. Chlorophyll fluorescence analysis or the potential quantum yield of PSII (Fv/Fm) in toluene exposed plants showed no significant differences between the control and the treated plants, whereas plants exposed to ethylbenzene showed significant differences or those parameters, specifically in Dracaena deremensis (Lemon lime), Dracaena sanderiana, Kalanchoe blossfeldiana, and Cordyline fruticosa. The Fv/Fm ratio can give insight into the ability of plants to tolerate (indoor) air pollution by volatile organic chemicals (VOC). This index can be used for identification of suitable plants for treating/sequestering VOCs in contaminated air.

  12. Revision of The Global Carbon Budget Due To Changing Air-sea Oxygen Fluxes

    Science.gov (United States)

    Plattner, G.-K.; Joos, F.; Stocker, T. F.

    A quantitative understanding of the carbon cycle is important to optimize global warming mitigation strategies. The classic method, applying an ocean model to esti- mate the partitioning of anthropogenic carbon between the global terrestrial and ocean carbon sinks has been complemented by various data-based methods. Here, we inves- tigate how global warming and volcanic eruptions affect sea-to-air oxygen (O2) fluxes and, in turn, the carbon budgets for the last two decades deduced from the observed trends in atmospheric carbon dioxide (CO2) and O2; the latter estimated from mea- surements of the ratio of oxygen to nitrogen (O2/N2) in air. By forcing a physical- biogeochemical climate model of intermediate complexity with reconstructed natu- ral and anthropogenic radiative forcing, we find a significant oceanic O2 outgassing mainly due to changes in ocean circulation and biological cycling (78%) and, to a lesser extent, due to surface warming (22%). Simulated sea-to-air O2 fluxes and ocean heat uptake rates are tightly correlated on multi-annual to multi-decadal time scales. A change in oceanic heat uptake of 1022 J corresponds to an increase in atmospheric O2/N2 of 1.56 per meg when correlating simulated heat fluxes and associated O2/N2 changes over the period 1900 to 2000. We combine this relation with data of ocean heat uptake and atmospheric O2/N2 and CO2. Thereby we attempt to account for inter- nal climate variability not readily reproduced by models for individual decades. The inferred terrestrial carbon sink for the 1990s is reduced by a factor of two compared with the most recent estimate by the Intergovernmental Panel on Climate Change (IPCC). This brings also into agreement calculated oceanic CO2 uptake rates with estimates from global carbon cycle models, which indicate a higher oceanic CO2 up- take during the 1990s than the 1980s.

  13. Ambient air sampling for radioactive air contaminants at Los Alamos National Laboratory: A large research and development facility

    Energy Technology Data Exchange (ETDEWEB)

    Eberhart, C.F.

    1998-09-01

    This paper describes the ambient air sampling program for collection, analysis, and reporting of radioactive air contaminants in and around Los Alamos National Laboratory (LANL). Particulate matter and water vapor are sampled continuously at more than 50 sites. These samples are collected every two weeks and then analyzed for tritium, and gross alpha, gross beta, and gamma ray radiation. The alpha, beta, and gamma measurements are used to detect unexpected radionuclide releases. Quarterly composites are analyzed for isotopes of uranium ({sup 234}U, {sup 235}U, {sup 238}U), plutonium ({sup 238}Pu, {sup 239/249}Pu), and americium ({sup 241}Am). All of the data is stored in a relational database with hard copies as the official records. Data used to determine environmental concentrations are validated and verified before being used in any calculations. This evaluation demonstrates that the sampling and analysis process can detect tritium, uranium, plutonium, and americium at levels much less than one percent of the public dose limit of 10 millirems. The isotopic results also indicate that, except for tritium, off-site concentrations of radionuclides potentially released from LANL are similar to typical background measurements.

  14. A simple model for the assessment of indoor radionuclide Pb-210 surface contamination due to the presence of radon

    Directory of Open Access Journals (Sweden)

    Mrđa Dušan S.

    2013-01-01

    Full Text Available The presented, very simplified model provides a possibility for estimation of surface Pb-210 activity, depending on the changes of Rn-222 concentration during the long-term radon presence inside the closed room. This can be useful for retrospective assessment of the average indoor radon concentration for certain historical period, based on the surface contamination by the radionuclide Pb-210 in a closed or poorly ventilated room over a long period of time. However, the surface Pb-210 contamination depends on the pattern of radon concentration changes, and in this model is supposed that the change of indoor radon concentration, which periodically enters the room, is affected only by the radioactive decay and the inserted amount of radon in each entry. So, each radon entry can be comprehended as a “net amount” of radon, or excess which remains inside the room due to radon’s periodical in-out flow. It is shown, that under the conditions of the model, the achieved average value of radon concentration of 275 Bq/m3, implies that the saturated surface contamination by the Pb-210 of 160 Bq/m2 after approximately 150 years. [Projekat Ministarstva nauke Republike Srbije, br. 171002: Nuclear Methods Investigations of Rare Processes and Cosmic Rays i br. 43002: Biosensing Technologies and Global System for Continuous Research and Integrated Management of ecosystems

  15. Dioxin-like PCB in indoor air contaminated with different sources

    Energy Technology Data Exchange (ETDEWEB)

    Heinzow, B.G.J.; Mohr, S.; Ostendorp, G. [Landesamt fuer Gesundheit und Arbeitssicherheit des Landes Schleswig-Holstein, Flintbek (Germany); Kerst, M.; Koerner, W. [Bayerisches Landesamt fuer Umweltschutz, Augsburg (Germany)

    2004-09-15

    Polychlorinated biphenyls (PCB) have been used in public building constructions for various purposes in the 1960s and 1970s, mainly as an additive to concrete, caulking, grout, paints, as a major constitutent of permanent elastic Thiokol rubber sealants and flame retardant coatings of acoustic ceiling tiles. Offgazing of semivolatile PCB from building materials can nowadays still result in considerable house-dust contamination and in indoor air concentrations exceeding 10,000 ng/m{sup 3}. In Germany, PCB levels in indoor air in non-occupational settings have been regulated with a tolerable total PCB concentration of 300 ng /m{sup 3} and an intervention level of 3000 ng/m{sup 3}. Lower re-entry criteria have been proposed by Michaud et al. Technical mixtures of PCB contain dioxin-like non- and mono-ortho substituted PCB congeners and are contaminated with trace amounts of polychlorinated dibenzodioxins (PCDD) and mainly dibenzofurans (PCDF), sharing overlapping toxic effects and physicochemical properties. We report here on levels of dioxinlike PCB measured in buildings with various PCB sources and correlations among PCDD/PCDF and dioxin-like PCB and di-ortho PCB.

  16. Impact of clay mineral on air oxidation of PAH-contaminated soils.

    Science.gov (United States)

    Biache, Coralie; Kouadio, Olivier; Lorgeoux, Catherine; Faure, Pierre

    2014-09-01

    This work investigated the impact of a clay mineral (bentonite) on the air oxidation of the solvent extractable organic matters (EOMs) and the PAHs from contaminated soils. EOMs were isolated from two coking plant soils and mixed with silica sand or bentonite. These samples, as well as raw soils and bentonite/soil mixtures, were oxidized in air at 60 and 100 °C for 160 days. Mineralization was followed by measuring the CO2 produced over the experiments. EOM, polycyclic aromatic compound (PAC), including PAH, contents were also determined. Oxidation led to a decrease in EOM contents and PAH concentrations, these diminutions were enhanced by the presence of bentonite. Transfer of carbon from EOM to insoluble organic matter pointed out a condensation phenomenon leading to a stabilization of the contamination. Higher mineralization rates, observed during the oxidation of the soil/bentonite mixtures, seem to indicate that this clay mineral had a positive influence on the transformation of PAC into CO2.

  17. Outbreak of Burkholderia cepacia complex bacteremia in a chemotherapy day care unit due to intrinsic contamination of an antiemetic drug

    Directory of Open Access Journals (Sweden)

    T Singhal

    2015-01-01

    Full Text Available Background: In the end of 2009, a large number of patients with cancer undergoing chemotherapy at the day care unit of a private hospital in Mumbai, India developed Burkholderia cepacia complex (BCC blood stream infection (BSI. Objective: The objectives were to identify the source of the outbreak and terminate the outbreak as rapidly as possible. Materials and Methods: All infection control protocols and processes were reviewed. Intensive training was started for all nursing staff involved in patient care. Cultures were sent from the environment (surfaces, water, air, intravenous fluids, disinfectants and antiseptics and opened/unopened medication. Results: A total of 13 patients with cancer with tunneled catheters were affected with BCC BSI. The isolates were of similar antimicrobial sensitivity. No significant breach of infection control protocols could be identified. Cultures from the prepared intravenous medication bags grew BCC. Subsequently, culture from unused vials of the antiemetic granisetron grew BCC, whereas those from the unopened IV fluid bag and chemotherapy medication were negative. On review, it was discovered that the outbreak started when a new brand of granisetron was introduced. The result was communicated to the manufacturer and the brand was withdrawn. There were no further cases. Conclusions: This outbreak was thus linked to intrinsic contamination of medication vials. We acknowledge a delay in identifying the source as we were concentrating more on human errors in medication preparation and less on intrinsic contamination. We recommend that in an event of an outbreak, unopened vials be cultured at the outset.

  18. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Bill

    1991-10-01

    In April 1990, Wright-Patterson Air Force Base (WPAFB), initiated an investigation to evaluate a potential Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) removal action to prevent, to the extent practicable, the offsite migration of contaminated ground water from WPAFB. WPAFB retained the services of the Environmental Management Operations (EMO) and its principle subcontractor, International Technology Corporation (IT) to complete Phase 1 of the environmental investigation of ground-water contamination at WPAFB. Phase 1 of the investigation involves the short-term evaluation and potential design for a program to remove ground-water contamination that appears to be migrating across the western boundary of Area C, and across the northern boundary of Area B along Springfield Pike. Primarily, Task 4 of Phase 1 focuses on collection of information at the Area C and Springfield Pike boundaries of WPAFB. This Sampling and Analysis Plan (SAP) has been prepared to assist in completion of the Task 4 field investigation and is comprised of the Quality Assurance Project Plan (QAPP) and the Field Sampling Plan (FSP).

  19. Internal dose assessment due to large area contamination: Main lessons drawn from the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Andrasi, A. [KFKI Atomic Energy Research Inst., Budapest (Hungary)

    1997-03-01

    The reactor accident at Chernobyl in 1986 beside its serious and tragic consequences provided also an excellent opportunity to check, test and validate all kind of environmental models and calculation tools which were available in the emergency preparedness systems of different countries. Assessment of internal and external doses due to the accident has been carried out for the population all over Europe using different methods. Dose predictions based on environmental model calculation considering various pathways have been compared with those obtained by more direct monitoring methods. One study from Hungary and one from the TAEA is presented shortly. (orig./DG)

  20. Integration of processes induced air flotation and photo-Fenton for treatment of residual waters contaminated with xylene

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Syllos S. da [Departamento Engenharia Quimica, NUPEG, Universidade Federal do Rio Grande do Norte, Campus Universitario, Lagoa Nova, Natal 59066-800, RN (Brazil); Chiavone-Filho, Osvaldo, E-mail: osvaldo@eq.ufrn.br [Departamento Engenharia Quimica, NUPEG, Universidade Federal do Rio Grande do Norte, Campus Universitario, Lagoa Nova, Natal 59066-800, RN (Brazil); Barros Neto, Eduardo L. de [Departamento Engenharia Quimica, NUPEG, Universidade Federal do Rio Grande do Norte, Campus Universitario, Lagoa Nova, Natal 59066-800, RN (Brazil); Nascimento, Claudio A.O. [Departamento de Engenharia Quimica, Escola Politecnica, Universidade de Sao Paulo, Cidade Universitaria, Sao Paulo 05508-900, SP (Brazil)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer We have studied the treatment of wastewater contaminated with hydrocarbons represented by the xylene, using these processes in an integrated mode: induced air flotation and photo-Fenton. Black-Right-Pointing-Pointer We have selected xylene as representative contaminant due to properties of toxicity, solubility in water and vapor pressure. Black-Right-Pointing-Pointer The manuscript presents a series of accurate experimental data that can be useful for material and energy optimization purposes in the xylene removal aiming the treatment of oil field produced water. - Abstract: Produced water in oil fields is one of the main sources of wastewater generated in the industry. It contains several organic compounds, such as benzene, toluene, ethyl benzene and xylene (BTEX), whose disposal is regulated by law. The aim of this study is to investigate a treatment of produced water integrating two processes, i.e., induced air flotation (IAF) and photo-Fenton. The experiments were conducted in a column flotation and annular lamp reactor for flotation and photodegradation steps, respectively. The first order kinetic constant of IAF for the wastewater studied was determined to be 0.1765 min{sup -1} for the surfactant EO 7. Degradation efficiencies of organic loading were assessed using factorial planning. Statistical data analysis shows that H{sub 2}O{sub 2} concentration is a determining factor in process efficiency. Degradations above 90% were reached in all cases after 90 min of reaction, attaining 100% mineralization in the optimized concentrations of Fenton reagents. Process integration was adequate with 100% organic load removal in 20 min. The results of the integration of the IAF with the photo-Fenton allowed to meet the effluent limits established by Brazilian legislation for disposal.

  1. Air pollution episodes in Stockholm regional background air due to sources in Europe and their effects on human population

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, C. [Swedish Meteorological and Hydrological Inst., Norrkoping (Sweden)], E-mail: camilla.andersson@smhi.se; Joensson, O. [Stockholm Univ. (Sweden). Dept. of Applied Environmental Science; Forsberg, B. [Umea Univ. (Sweden), Occupational and Environmental Medicine; Johansson, C. [Environmental and Health Administration, Stockholm (Sweden)

    2013-09-01

    Using air quality measurements, we categorized air pollution according to source sectors in a rural background environment in southern Sweden based on hourly air-mass backward trajectories during 1997-2010. Concentrations of fine (PM{sub 2.5}) and sum of fine and coarse particulate matter (PM{sub 10}), accumulation mode particle number, black carbon and surface ozone were 4.0, 3.9, 4.5, 6.8 and 1.3 times higher, respectively, in air masses from the southeast as compared with those in air masses from the cleanest sector in the northwest, consistent with air-mass transport over areas with relatively high emissions of primary particulate matter (PM) and secondary PM precursors. The highest ultrafine particle numbers were associated with clean air from the northwest. We estimate that almost 7.8% and 0.6% higher premature human mortality is caused by PM{sub 2.5} and ozone exposure, respectively, when air originates from the southeast as compared with that when air originates from the northwest. Reductions of emissions in eastern Europe would reduce the highest air pollution concentrations and associated health risks. However, since air masses from the southwest are more frequent, emissions in the western part of Europe are more important for annual mean premature mortality. (orig.)

  2. Novel atmospheric pressure plasma device releasing atomic hydrogen: reduction of microbial-contaminants and OH radicals in the air

    Science.gov (United States)

    Nojima, Hideo; Park, Rae-Eun; Kwon, Jun-Hyoun; Suh, Inseon; Jeon, Junsang; Ha, Eunju; On, Hyeon-Ki; Kim, Hye-Ryung; Choi, Kyoung Hui; Lee, Kwang-Hee; Seong, Baik-Lin; Jung, Hoon; Kang, Shin Jung; Namba, Shinichi; Takiyama, Ken

    2007-01-01

    A novel atmospheric pressure plasma device releasing atomic hydrogen has been developed. This device has specific properties such as (1) deactivation of airborne microbial-contaminants, (2) neutralization of indoor OH radicals and (3) being harmless to the human body. It consists of a ceramic plate as a positive ion generation electrode and a needle-shaped electrode as an electron emission electrode. Release of atomic hydrogen from the device has been investigated by the spectroscopic method. Optical emission of atomic hydrogen probably due to recombination of positive ions, H+(H2O)n, generated from the ceramic plate electrode and electrons emitted from the needle-shaped electrode have been clearly observed in the He gas (including water vapour) environment. The efficacy of the device to reduce airborne concentrations of influenza virus, bacteria, mould fungi and allergens has been evaluated. 99.6% of airborne influenza virus has been deactivated with the operation of the device compared with the control test in a 1 m3 chamber after 60 min. The neutralization of the OH radical has been investigated by spectroscopic and biological methods. A remarkable reduction of the OH radical in the air by operation of the device has been observed by laser-induced fluorescence spectroscopy. The cell protection effects of the device against OH radicals in the air have been observed. Furthermore, the side effects have been checked by animal experiments. The harmlessness of the device has been confirmed.

  3. Iatrogenic Complications in Five Patients with Upper Gastrointestinal Bleeding due to Ambient Air: Case Series and Literature Review

    Directory of Open Access Journals (Sweden)

    Christine N. Manser

    2012-04-01

    Full Text Available Despite the increasing use of carbon dioxide for endoscopies during the last years, ambient air is still used. The amount of air depends on several factors such as examination time, presumable diameter of the endoscope channel and of course active use of air by the operator. Although endoscopic complications due to ambient air in the gastrointestinal (GI tract are a rare observation and mostly described in the colon, we report five cases in the upper GI tract due to insufflating large amounts of air through the endoscopes. All 5 patients needed an emergency upper endoscopy for acute presumed upper GI bleeding. In two cases both esophageal variceal bleeding and ulcer bleeding were detected; the fifth case presented with a bleeding due to gastric cancer. Due to insufflation of inadequate amounts of air through the endoscope channel, all patients deteriorated in circulation and ventilation. Two rumenocenteses and consecutively three laparotomies had to be performed in three patients. In the other two, gastroscopies had to be stopped for an emergency computed tomography. All critical incidents were believed to be a consequence of a long-lasting examination with use of too much air. Therefore in emergency situations, endoscopies should be performed with either submersion, low air flow pumps or even better by the use of carbon dioxide.

  4. Plasticizers, antioxidants, and other contaminants found in air delivered by PVC tubing used in respiratory therapy.

    Science.gov (United States)

    Hill, Sandra S; Shaw, Brenda R; Wu, Alan H B

    2003-06-01

    Of the many compounds that leach from respiratory therapy tubing into air passing through it, we selected five compounds to analyze. The five compounds are known to be potentially carcinogenic, toxic or known to induce estrogenic activity. Parts-per-million and parts-per-billion concentrations of these species were found in the air passing through the tubing: the plasticizers di-(2-ethylhexyl) phthalate (DEHP) and di-ethyl phthalate (DEP), the antioxidants butylated hydroxy toluene (BHT) and p-nonylphenol (p-NP), and the contaminant (from commercial preparation of DEHP) 2-ethylhexanol (2-EH). These levels are high enough to cause some concern about exposure for patients who use oxygen on a long-term basis, those sensitive or allergic to these species, or those with asthma. A method was developed for analysis of solid tubing samples, showing great variability in concentrations of small, volatile molecules from sample to sample. A method was also developed for pre-concentration of small molecules onto Tenax adsorbants from air passing through the tubing. Both solid samples and adsorbant loaded with analyte were analyzed by direct dynamic thermal desorption gas chromatography mass spectrometry (GCMS). This study does not imply that adverse reactions by patients to chemical compounds leaching from respiratory medical tubing will occur but that further investigation is warranted.

  5. Study the air pollution due to Dorud Cement Plant (in Iran

    Directory of Open Access Journals (Sweden)

    Vahid Mokhtari

    2016-09-01

    Full Text Available Cement industry is one of the most important industries in the country. Dorud Cement Plant is one of the largest and oldest Iran's cement factories, which is working in the center of the city of Dorud. In this study, aimed to investigate air pollution resulting from Dorud cement plant, the parameters of CO, CO2, O2, NO, NO2, NOx, SO2, dry dust particles, particles weight and environmental particulates of PM10 and PM2.5 were measured with conventional methods of measuring emissions from industrial chimneys and by using automatic measuring equipment, and the rates of emissions from the chimneys of the plant were calculated during a working year. These measurements were made over three months, from February 20, 2015 to May 21, 2015, at 3 stations of Link1-k1, Link2-k1 and Link3-k1, which are the chimneys of the three-lines of the plant. It was found in this study that the chimney No. 3 enters the maximum contaminant into the environment. The results also showed that based on the standards defined for the cement industry, Dorud cement plant meets the relative optimal conditions in terms of comparing performance with the standards, and the emissions from the factory are less than the enacted standards for this industry. Also, the preventive measures and equipment for reducing emissions established in this industrial unit have a relative utility. In this study, the factors including type of raw materials used, old production lines and old factory equipment, type of producing cement and proximity to the city were determined as main reasons for the emissions produced by this industry. Also, some management solutions such as the use of environment designing inside the manufacturing process of the plant and outside the plant, using flame-reducing, construction of a new phase and relocating the plant were suggested to reduce emissions from Dorud cement plants.

  6. Fate of Potential Contaminants Due to Disposal of Olive Mill Wastewaters in Unprotected Evaporation Ponds.

    Science.gov (United States)

    Kavvadias, V; Elaiopoulos, K; Theocharopoulos, Sid; Soupios, P

    2017-03-01

    The disposal of olive mill wastewaters (OMW) in shallow and unprotected evaporation ponds is a common, low-cost management practice, followed in Mediterranean countries. So far, the fate of potential soil pollutants in areas located near evaporation ponds is not adequately documented. This study investigates the extent in which the long-term disposal of OMW in evaporation ponds can affect the soil properties of the area located outside the evaporation pond and assesses the fate of the pollution loads of OMW. Four soil profiles situated outside and around the down slope side of the disposal area were excavated. The results showed considerable changes in concentration of soil phenols at the down-site soil profiles, due to the subsurface transport of the OMW. In addition, excessive concentrations of NH4(+), PO4(3-) and phenols were recorded in liquid samples taken from inside at the bottom of the soil profiles. It is concluded that unprotected evaporation ponds located in light texture soils pose a serious threat to favour soil and water pollution.

  7. An Evaluation of Antifungal Agents for the Treatment of Fungal Contamination in Indoor Air Environments

    Directory of Open Access Journals (Sweden)

    Senthaamarai Rogawansamy

    2015-06-01

    Full Text Available Fungal contamination in indoor environments has been associated with adverse health effects for the inhabitants. Remediation of fungal contamination requires removal of the fungi present and modifying the indoor environment to become less favourable to growth.  This may include treatment of indoor environments with an antifungal agent to prevent future growth. However there are limited published data or advice on chemical agents suitable for indoor fungal remediation. The aim of this study was to assess the relative efficacies of five commercially available cleaning agents with published or anecdotal use for indoor fungal remediation. The five agents included two common multi-purpose industrial disinfectants (Cavicide® and Virkon®, 70% ethanol, vinegar (4.0%-4.2% acetic acid, and a plant-derived compound (tea tree (Melaleuca alternifolia oil tested in both a liquid and vapour form. Tea tree oil has recently generated interest for its antimicrobial efficacy in clinical settings, but has not been widely employed for fungal remediation. Each antifungal agent was assessed for fungal growth inhibition using a disc diffusion method against a representative species from two common fungal genera, (Aspergillus fumigatus and Penicillium chrysogenum, which were isolated from air samples and are commonly found in indoor air. Tea tree oil demonstrated the greatest inhibitory effect on the growth of both fungi, applied in either a liquid or vapour form. Cavicide® and Virkon® demonstrated similar, although less, growth inhibition of both genera. Vinegar (4.0%–4.2% acetic acid was found to only inhibit the growth of P. chrysogenum, while 70% ethanol was found to have no inhibitory effect on the growth of either fungi. There was a notable inhibition in sporulation, distinct from growth inhibition after exposure to tea tree oil, Virkon®, Cavicide® and vinegar. Results demonstrate that common cleaning and antifungal agents differ in their capacity to

  8. Impact of airflow interaction on inhaled air quality and transport of contaminants in rooms with personalized and total volume ventilation

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Cermak, Radim; Kovar, O.

    2003-01-01

    The impact of airflow interaction on inhaled air quality and transport of contaminants between occupants was studied in regard to pollution from floor covering, human bioeffluents and exhaled air, with combinations of two personalized ventilation systems (PV) with mixing and displacement ventilat......The impact of airflow interaction on inhaled air quality and transport of contaminants between occupants was studied in regard to pollution from floor covering, human bioeffluents and exhaled air, with combinations of two personalized ventilation systems (PV) with mixing and displacement...... ventilation. In total, 80 L/s of clean air supplied at 20°C was distributed between the ventilation systems at different combinations of personalized airflow rate. Two breathing thermal manikins were used to simulate occupants in a full-scale test room. Regardless of the airflow interaction, the inhaled air......, at low flow rates of personalized air a decrease in the quality of the inhaled air compared to displacement ventilation alone. The PV system supplying air against the face improved the ventilation efficiency in regard to the floor pollution up to 20 times and up to 13 times in regard to bioeffluents...

  9. Evaluation of bacterial contamination on surgical drapes following use of the Bair Hugger(®) forced air warming system.

    Science.gov (United States)

    Occhipinti, Lindsay L; Hauptman, Joe G; Greco, Justin J; Mehler, Stephen J

    2013-12-01

    This pilot study determined the rate of bacterial contamination on surgical drapes of small animal patients warmed intra-operatively with the Bair Hugger(®) forced air warming system compared to a control method. Surgical drapes of 100 patients undergoing clean surgical procedures were swabbed with aerobic culturettes at the beginning and end of surgery. Samples were cultured on Trypticase soy agar. Contamination of the surgical drapes was identified in 6/98 cases (6.1%). There was no significant difference in the number of contaminated surgical drapes between the Bair Hugger(®) and control groups (P = 0.47).

  10. Modeling of the fate of radionuclides in urban sewer systems after contamination due to nuclear or radiological incidents.

    Science.gov (United States)

    Urso, L; Kaiser, J C; Andersson, K G; Andorfer, H; Angermair, G; Gusel, C; Tandler, R

    2013-04-01

    After an accidental radioactive contamination by aerosols in inhabited areas, the radiation exposure to man is determined by complex interactions between different factors such as dry or wet deposition, different types of ground surfaces, chemical properties of the radionuclides involved and building development as well as dependence on bomb construction e.g. design and geometry. At short-term, the first rainfall is an important way of natural decontamination: deposited radionuclides are washed off from surfaces and in urban areas the resulting contaminated runoff enters the sewer system and is collected in a sewage plant. Up to now the potential exposure caused by this process has received little attention and is estimated here with simulation models. The commercial rainfall-runoff model for urban sewer systems KANAL++ has been extended to include transport of radionuclides from surfaces through the drainage to various discharge facilities. The flow from surfaces is modeled by unit hydrographs, which produce boundary conditions for a system of 1d coupled flow and transport equations in a tube system. Initial conditions are provided by a map of surface contamination which is produced by geo-statistical interpolation of γ-dose rate measurements taking into account the detector environment. The corresponding methodology is implemented in the Inhabited Area Monitoring Module (IAMM) software module as part of the European decision system JRODOS. A hypothetical scenario is considered where a Radiation Dispersal Device (RDD) with Cs-137 is detonated in a small inhabited area whose drainage system is realistically modeled. The transition of deposited radionuclides due to rainfall into the surface runoff is accounted for by different nuclide-specific entrainment coefficients for paved and unpaved surfaces. The concentration of Cs-137 in water is calculated at the nodes of the drainage system and at the sewage treatment plant. The external exposure to staff of the

  11. Air pollution due to traffic, air quality monitoring along three sections of National Highway N-5, Pakistan.

    Science.gov (United States)

    Ali, Mahboob; Athar, Makshoof

    2008-01-01

    Transportation system has contributed significantly to the development of human civilization; on the other hand it has an enormous impact on the ambient air quality in several ways. In this paper the air and noise pollution at selected sites along three sections of National Highway was monitored. Pakistan National Highway Authority has started a Highway Improvement program for rehabilitations and maintenance of National highways to improve the traffic flows, and would ultimately improve the air quality along highways. The ambient air quality and noise level was monitored at nine different locations along these sections of highways to quantify the air pollution. The duration of monitoring at individual location was 72 h. The most of the sampling points were near the urban or village population, schools or hospitals, in order to quantify the air pollution at most affected locations along these roads. A database consisting of information regarding the source of emission, local metrology and air quality may be created to assess the profile of air quality in the area.

  12. Association of plant injury with an air contaminant in a controlled environment facility

    Energy Technology Data Exchange (ETDEWEB)

    Knudson, L.L.; Tibbitts, T.W.

    1974-01-01

    Gaseous compounds are common, yet seldom recognized contaminants in controlled environments. Injury to several plant species has been observed in the Biotron which uses trichloroethylene as a coolant in its centrally controlled system. Sometimes this compound is present in the rooms at an average level of 2 ppm, as measured by gas chromatography. Injury symptoms, which vary between species, are characteristic of air pollution injury. Present studies with Tagetes patula show a distinctive necrosis on the upper leaf surfaces. Experiments are being conducted to determine whether trichloroethylene is the agent involved and to investigate aspects of the physiology of injury utilizing a procedure which may be applicable to other long-term, low-level pollution studies.

  13. Changes in tropospheric composition and air quality due to stratospheric ozone depletion.

    Science.gov (United States)

    Solomon, Keith R; Tang, Xiaoyan; Wilson, Stephen R; Zanis, Prodromos; Bais, Alkiviadis F

    2003-01-01

    Increased UV-B through stratospheric ozone depletion leads to an increased chemical activity in the lower atmosphere (the troposphere). The effect of stratospheric ozone depletion on tropospheric ozone is small (though significant) compared to the ozone generated anthropogenically in areas already experiencing air pollution. Modeling and experimental studies suggest that the impacts of stratospheric ozone depletion on tropospheric ozone are different at different altitudes and for different chemical regimes. As a result the increase in ozone due to stratospheric ozone depletion may be greater in polluted regions. Attributable effects on concentrations are expected only in regions where local emissions make minor contributions. The vertical distribution of NOx (NO + NO2), the emission of volatile organic compounds and the abundance of water vapor, are important influencing factors. The long-term nature of stratospheric ozone depletion means that even a small increase in tropospheric ozone concentration can have a significant impact on human health and the environment. Trifluoroacetic acid (TFA) and chlorodifluoroacetic acid (CDFA) are produced by the atmospheric degradation of hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs). TFA has been measured in rain, rivers, lakes, and oceans, the ultimate sink for these and related compounds. Significant anthropogenic sources of TFA other than degradation HCFCs and HFCs have been identified. Toxicity tests under field conditions indicate that the concentrations of TFA and CDFA currently produced by the atmospheric degradation of HFCs and HCFCs do not present a risk to human health and the environment. The impact of the interaction between ozone depletion and future climate change is complex and a significant area of current research. For air quality and tropospheric composition, a range of physical parameters such as temperature, cloudiness and atmospheric transport will modify the impact of UV-B. Changes in the

  14. Air sparging as a supporting measure to redevelopment of a LCFC-contaminated industrial site; Air-Sparging als begleitende Sanierungsmassnahme an einem LCKW-kontaminierten Industriestandort

    Energy Technology Data Exchange (ETDEWEB)

    Breh, W.; Suttheimer, J. [Karlsruhe Univ. (T.H.) (Germany). Lehrstuhl fuer Angewandte Geologie; Holub, B. [G.U.T Linz (Austria)

    1998-12-31

    On a company ground in Vorchdorf, Austria, from the 23{sup rd} to 26{sup th} of July 1996 an air-sparging experiment has been carried out as a supporting measure to a running redevelopment of an LCKW-contamination case. On this occasion compressed air, from which the oil had been extracted, was blown into the contaminated aquifer through a well with a maximum excess pressure of 0,6 MPa. The blowing-in of compressed air caused a mobilisation of the harmful substances in the ground water and the soil air. As a result circa 2,7 kg LCKW could be removed from the underground through neighbouring ground water and soil air wells. For the observed period of time this meant a tripling of the rate of discharge. On the basis of the obtained data we suggested a routine interval of blowing in compressed air into the well 1516. A blowing-in of compressed air into the highly contaminated wells 1617 and 1625 can not be realised until the construction of upstream situated injection wells, because of the danger of an uncontrollable spread of the harmful substances. (orig.) [Deutsch] Auf einem Firmengelaende in Vorchdorf, Oesterreich, wurde vom 23.07. bis 26.07.1996 ein Air-Sparging-Versuch als unterstuetzende Massnahme zur laufenden hydraulisch-pneumatischen Sanierung eines LCKW-Schadensfalles durchgefuehrt. Hierbei wurde entoelte Druckluft ueber einen Brunnen mit einem maximalen Ueberdruck von 600 mbar in den kontaminierten Aquifer eingeblasen. Die Drucklufteinblasung fuehrte zu einer Mobilisierung von Schadstoffen im Grundwasser und in der Bodenluft, so dass ueber benachbarte Grundwasser- und Bodenluftfoerderbrunnen ca. 2,7 kg LCKW aus dem Untergrund entfernt werden konnten. Fuer den Beobachtungszeitraum bedeutet dies eine Verdreifachung des Schadstoffaustrags. Aufgrund der gewonnenen Daten wird ein routinemaessiger Intervallbetrieb der Drucklufteinblasung in einen der Brunnen vorgeschlagen. Fuer zwei kontaminierte Brunnen ist eine Drucklufteinblasung wegen der Gefahr einer

  15. Evaluation of bioaerosol sampling techniques for the detection of Chlamydophila psittaci in contaminated air.

    Science.gov (United States)

    Van Droogenbroeck, Caroline; Van Risseghem, Marleen; Braeckman, Lutgart; Vanrompay, Daisy

    2009-03-16

    Chlamydophila (C.) psittaci, a category B bioterrorism agent, causes respiratory disease in birds and psittacosis or parrot fever in man. The disease spreads aerogenically and no vaccines are available for either birds or man. Highly sensitive C. psittaci bioaerosol monitoring methods are unavailable. We evaluated: (1) dry filtration for collecting C. psittaci from contaminated air using different samplers and membrane filters, (2) impingement into different liquid collection media by use of the AGI-30 impinger and the BioSampler and (3) impaction into newly designed C. psittaci media utilizing the MAS-100 aerosol impactor. For personal bioaerosol sampling, we recommend the use of a gelatin filter in combination with the IOM inhalable dust sampler at an airflow rate of 2L/min. This allowed the detection of 10 organisms of C. psittaci by both PCR and culture. For stationary bioaerosol monitoring, sampling 1000L of air in 10min with the MAS-100 impactor and ChlamyTrap 1 impaction medium was most efficient and made it possible to detect 1 and 10 C. psittaci organisms by PCR and culture, respectively. ChlamyTrap 1 in combination with the MAS-100 impactor might also be applicable for bioaerosol monitoring of viruses.

  16. Air purification from TCE and PCE contamination in a hybrid bioreactors and biofilter integrated system.

    Science.gov (United States)

    Tabernacka, Agnieszka; Zborowska, Ewa; Lebkowska, Maria; Borawski, Maciej

    2014-01-15

    A two-stage waste air treatment system, consisting of hybrid bioreactors (modified bioscrubbers) and a biofilter, was used to treat waste air containing chlorinated ethenes - trichloroethylene (TCE) and tetrachloroethylene (PCE). The bioreactor was operated with loadings in the range 0.46-5.50gm(-3)h(-1) for TCE and 2.16-9.02gm(-3)h(-1) for PCE. The biofilter loadings were in the range 0.1-0.97gm(-3)h(-1) for TCE and 0.2-2.12gm(-3)h(-1) for PCE. Under low pollutant loadings, the efficiency of TCE elimination was 23-25% in the bioreactor and 54-70% in the biofilter. The efficiency of PCE elimination was 44-60% in the bioreactor and 50-75% in the biofilter. The best results for the bioreactor were observed one week after the pollutant loading was increased. However, the process did not stabilize. In the next seven days contaminant removal efficiency, enzymatic activity and biomass content were all diminished.

  17. Using Geophysical Signatures to Investigate Temporal Changes Due to Source Reduction in the Subsurface Contaminated with Hydrocarbons

    Science.gov (United States)

    We investigated the geophysical response to subsurface hydrocarbon contamination source removal. Source removal by natural attenuation or by engineered bioremediation is expected to change the biological, chemical, and physical environment associated with the contaminated matrix....

  18. Cat serum contamination by phthalates, PCBs, and PBDEs versus food and indoor air.

    Science.gov (United States)

    Braouezec, Clélie; Enriquez, Brigitte; Blanchard, Martine; Chevreuil, Marc; Teil, Marie-Jeanne

    2016-05-01

    A wide variety of endocrine disrupting compounds (EDCs) with semi-volatile properties are emitted to indoor air and, thus, humans might get exposed to these compounds. Pet cats spend the major part of their lifetime at home and might integrate indoor contamination so that they could mirror the human exposure. Three classes of EDCs, polybromodiphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and phthalates (PAEs), were simultaneously considered and quantified in the serum of cats (Felis silvestris catus) living in the Paris area (France). The main compound concentrations by decreasing importance order were as follows: for PAEs, di-n-butyl phthalate (79,900 ng L(-1)) next di-iso-butyl phthalate (53,200 ng L(-1)), di-iso-nonyl phthalate (43,800 ng L(-1)), and di-ethylhexyl phthalate (32,830 ng L(-1)); for PCBs, CB153 (1378 ng L(-1)) next CB52 (509 ng L(-1)), CB101 (355 ng L(-1)), CB110 (264 ng L(-1)), and CB118 (165 ng L(-1)); and for PBDEs, BDE 153/154 (35 ng L(-1)) next BDE47 (10.7 ng L(-1)). Total serum concentrations as mean ± standard deviation were 107 ± 98 μg L(-1) for ∑9PAEs, 2799 ± 944 ng L(-1) for ∑19PCBs, and 56 ± 21 ng L(-1) for ∑9BDEs. The three chemical groups were found in cat food: 0.088 ng g(-1) for ∑9BDEs, 1.7 ng g(-1) for ∑19PCBs, and 2292 ng g(-1) for ∑9PAEs and in indoor air: 0.063 ng m(-3) for ∑9BDEs, 1.5 ng m(-3) for ∑19PCBs, and 848 ng m(-3) for ∑9PAEs. Contaminant intake by food ingestion was approximately 100-fold higher than that by indoor air inhalation.

  19. Removal of methanethiol, dimethyl sulfide, dimethyl disulfide, and hydrogen sulfide from contaminated air by Thiobacillus thioparus TK-m.

    OpenAIRE

    Kanagawa, T; Mikami, E.

    1989-01-01

    Methanethiol, dimethyl sulfide, dimethyl disulfide, and hydrogen sulfide were efficiently removed from contaminated air by Thiobacillus thioparus TK-m and oxidized to sulfate stoichiometrically. More than 99.99% of dimethyl sulfide was removed when the load was less than 4.0 g of dimethyl sulfide per g (dry cell weight) per day.

  20. MODELING THE ANOMALY OF SURFACE NUMBER DENSITIES OF GALAXIES ON THE GALACTIC EXTINCTION MAP DUE TO THEIR FIR EMISSION CONTAMINATION

    Energy Technology Data Exchange (ETDEWEB)

    Kashiwagi, Toshiya; Suto, Yasushi; Taruya, Atsushi; Yahata, Kazuhiro [Department of Physics, The University of Tokyo, Tokyo 113-0033 (Japan); Kayo, Issha [Department of Physics, Toho University, Funabashi, Chiba 274-8510 (Japan); Nishimichi, Takahiro, E-mail: kashiwagi@utap.phys.s.u-tokyo.ac.jp [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8568 (Japan)

    2015-02-01

    The most widely used Galactic extinction map is constructed assuming that the observed far-infrared (FIR) fluxes come entirely from Galactic dust. According to the earlier suggestion by Yahata et al., we consider how FIR emission of galaxies affects the SFD map. We first compute the surface number density of Sloan Digital Sky Survey (SDSS) DR7 galaxies as a function of the r-band extinction, A {sub r,} {sub SFD}. We confirm that the surface densities of those galaxies positively correlate with A {sub r,} {sub SFD} for A {sub r,} {sub SFD} < 0.1, as first discovered by Yahata et al. for SDSS DR4 galaxies. Next we construct an analytical model to compute the surface density of galaxies, taking into account the contamination of their FIR emission. We adopt a log-normal probability distribution for the ratio of 100 μm and r-band luminosities of each galaxy, y ≡ (νL){sub 100} {sub μm}/(νL) {sub r}. Then we search for the mean and rms values of y that fit the observed anomaly, using the analytical model. The required values to reproduce the anomaly are roughly consistent with those measured from the stacking analysis of SDSS galaxies. Due to the limitation of our statistical modeling, we are not yet able to remove the FIR contamination of galaxies from the extinction map. Nevertheless, the agreement with the model prediction suggests that the FIR emission of galaxies is mainly responsible for the observed anomaly. Whereas the corresponding systematic error in the Galactic extinction map is 0.1-1 mmag, it is directly correlated with galaxy clustering and thus needs to be carefully examined in precision cosmology.

  1. Water quality concerns due to forest fires: polycyclic aromatic hydrocarbons (PAH) contamination of groundwater from mountain areas.

    Science.gov (United States)

    Mansilha, C; Carvalho, A; Guimarães, P; Espinha Marques, J

    2014-01-01

    Water quality alterations due to forest fires may considerably affect aquatic organisms and water resources. These impacts are cumulative as a result of pollutants mobilized from fires, chemicals used to fight fire, and postfire responses. Few studies have examined postfire transport into water resources of trace elements, including the polycyclic aromatic hydrocarbons (PAH), which are organic pollutants produced during combustion and are considered carcinogenic and harmful to humans. PAH are also known to adversely affect survival, growth, and reproduction of many aquatic species. This study assessed the effects of forest wildfires on groundwater from two mountain regions located in protected areas from north and central Portugal. Two campaigns to collect water samples were performed in order to measure PAH levels. Fifteen of 16 studied PAH were found in groundwater samples collected at burned areas, most of them at concentrations significantly higher than those found in control regions, indicating aquifer contamination. The total sum of PAH in burned areas ranged from 23.1to 95.1 ng/L with a median of 62.9 ng/L, which is one- to sixfold higher than the average level measured in controls (16.2 ng/L). In addition, in control samples, the levels of light PAH with two to four rings were at higher levels than heavy PAH with five or six rings, thus showing a different profile between control and burned sites. The contribution of wildfires to groundwater contamination by PAH was demonstrated, enabling a reliable assessment of the impacts on water quality and preparation of scientifically based decision criteria for postfire forest management practices.

  2. Is Distant Pollution Contaminating Local Air? Analyzing the Origins of Atmospheric Aerosols

    Directory of Open Access Journals (Sweden)

    David Geng

    2012-01-01

    Full Text Available Understanding the origin of aerosols in the atmosphere is important because of visual pollution, climate impacts, and deleterious health effects due to the inhalation of fine particles. This research analyzed aerosols characterized by their chloride, sulfate, and nitrate content as a function of size over a 3-month period. Due to wind patterns over coal-burning power plants, a higher concentration of local sulfate pollution was expected. Aerosols were harvested on the Purdue University campus using a high-volume air sampler with glass fiber filters and a five-stage impactor that separates the aerosols into five sizes. The filters were extracted in water to dissolve anions and the solution was analyzed using high-pressure liquid ion chromatography. Only trace amounts of chloride with no distinct patterns in size were detected. In total, nitrate content ranged from 0.12 to 2.10 μg/m3 and sulfate content ranged from 0.44 to 6.45 μg/m3 over a 3-month period. As for fine particles, a higher concentration of sulfate was observed. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT model determines air mass origin, and in this study, higher total sulfate content was observed when the air mass moved out of the southwest, and higher total nitrate content was observed when the air mass originated from the southeast. The author concluded that small particles resulted in sulfate from sulfur dioxide, typically from gas to particle conversion. High sulfur dioxide levels are directly correlated with coal-burning power plant density. Small particulate sulfate found in West Lafayette, Indiana, was determined to originate primarily from power plants in southwest Indiana. Though the results do show a significant amount of potentially harmful aerosols in West Lafayette, there is still further research to be done concerning isotopic composition of those particles in attempts to better explain the chemical pathways.

  3. Reducing position error signal (PES) due to disk vibration using an air shroud

    Science.gov (United States)

    He, Zhimin; Du, Chunling; Mou, Jianqiang; Ong, Eng Hong

    2008-04-01

    The advances in magnetic recording technology demand higher magnetic head positioning accuracy and faster disk rotation speed. However, the higher rotational speed of disk generates the greater flow-induced vibration known as disk flutter, which causes the increase of the track misregistration (TMR). To overcome the issue, an air shroud is presented to reduce disk vibration and position error signal (PES) for magnetic recording. Computational fluid mechanics simulations are performed to study the flow pattern surrounding a disk with an air shroud for different openings. The air-bearing stiffness and damping effects of the disk spindle assembly with an air shroud are evaluated. Based on the computational fluid dynamics (CFD) simulation, the air shroud is prototyped and the disk vibrations with and without the air shroud at different disk rotation speeds are experimentally investigated using a laser Doppler vibrometer (LDV). Significant disk vibration reductions are attained while a shroud is installed onto a disk at certain disk rotation speeds. PESs are also measured for the cases with and without an air shroud during servo implementation. Reductions of PESs are observed when an air shroud is installed at some disk rotation speeds.

  4. Control of aerosol contaminants in indoor air: combining the particle concentration reduction with microbial inactivation.

    Science.gov (United States)

    Grinshpun, Sergey A; Adhikari, Atin; Honda, Takeshi; Kim, Ki Youn; Toivola, Mika; Rao, K S Ramchander; Reponen, Tiina

    2007-01-15

    An indoor air purification technique, which combines unipolar ion emission and photocatalytic oxidation (promoted by a specially designed RCI cell), was investigated in two test chambers, 2.75 m3 and 24.3 m3, using nonbiological and biological challenge aerosols. The reduction in particle concentration was measured size selectively in real-time, and the Air Cleaning Factor and the Clean Air Delivery Rate (CADR) were determined. While testing with virions and bacteria, bioaerosol samples were collected and analyzed, and the microorganism survival rate was determined as a function of exposure time. We observed that the aerosol concentration decreased approximately 10 to approximately 100 times more rapidly when the purifier operated as compared to the natural decay. The data suggest that the tested portable unit operating in approximately 25 m3 non-ventilated room is capable to provide CADR-values more than twice as great than the conventional closed-loop HVAC system with a rating 8 filter. The particle removal occurred due to unipolar ion emission, while the inactivation of viable airborne microorganisms was associated with photocatalytic oxidation. Approximately 90% of initially viable MS2 viruses were inactivated resulting from 10 to 60 min exposure to the photocatalytic oxidation. Approximately 75% of viable B. subtilis spores were inactivated in 10 min, and about 90% or greater after 30 min. The biological and chemical mechanisms that led to the inactivation of stress-resistant airborne viruses and bacterial spores were reviewed.

  5. Bioaccumulation Potential Of Air Contaminants: Combining Biological Allometry, Chemical Equilibrium And Mass-Balances To Predict Accumulation Of Air Pollutants In Various Mammals

    Energy Technology Data Exchange (ETDEWEB)

    Veltman, Karin; McKone, Thomas E.; Huijbregts, Mark A.J.; Hendriks, A. Jan

    2009-03-01

    In the present study we develop and test a uniform model intended for single compartment analysis in the context of human and environmental risk assessment of airborne contaminants. The new aspects of the model are the integration of biological allometry with fugacity-based mass-balance theory to describe exchange of contaminants with air. The developed model is applicable to various mammalian species and a range of chemicals, while requiring few and typically well-known input parameters, such as the adult mass and composition of the species, and the octanol-water and air-water partition coefficient of the chemical. Accumulation of organic chemicals is typically considered to be a function of the chemical affinity forlipid components in tissues. Here, we use a generic description of chemical affinity for neutral and polar lipids and proteins to estimate blood-air partition coefficients (Kba) and tissue-air partition coefficients (Kta) for various mammals. This provides a more accurate prediction of blood-air partition coefficients, as proteins make up a large fraction of total blood components. The results show that 75percent of the modeled inhalation and exhalation rate constants are within a factor of 2 from independent empirical values for humans, rats and mice, and 87percent of the predicted blood-air partition coefficients are within a factor of 5 from empirical data. At steady-state, the bioaccumulation potential of air pollutants is shown to be mainly a function of the tissue-air partition coefficient and the biotransformation capacity of the species and depends weakly on the ventilation rate and the cardiac output of mammals.

  6. The burden of COPD mortality due to ambient air pollution in Guangzhou, China

    Science.gov (United States)

    Li, Li; Yang, Jun; Song, Yun-Feng; Chen, Ping-Yan; Ou, Chun-Quan

    2016-05-01

    Few studies have investigated the chronic obstructive pulmonary disease (COPD) mortality fraction attributable to air pollution and modification by individual characteristics of air pollution effects. We applied distributed lag non-linear models to assess the associations between air pollution and COPD mortality in 2007–2011 in Guangzhou, China, and the total COPD mortality fraction attributable to air pollution was calculated as well. We found that an increase of 10 μg/m3 in particulate matter with an aerodynamic diameter of 10 μm or less (PM10), sulfur dioxide (SO2) and nitrogen dioxide (NO2) was associated with a 1.58% (95% confidence interval (CI): 0.12–3.06%), 3.45% (95% CI: 1.30–5.66%) and 2.35% (95% CI: 0.42–4.32%) increase of COPD mortality over a lag of 0–15 days, respectively. Greater air pollution effects were observed in the elderly, males and residents with low educational attainment. The results showed 10.91% (95% CI: 1.02–9.58%), 12.71% (95% CI: 5.03–19.85%) and 13.38% (95% CI: 2.67–22.84%) COPD mortality was attributable to current PM10, SO2 and NO2 exposure, respectively. In conclusion, the associations between air pollution and COPD mortality differed by individual characteristics. There were remarkable COPD mortality burdens attributable to air pollution in Guangzhou.

  7. The burden of COPD mortality due to ambient air pollution in Guangzhou, China.

    Science.gov (United States)

    Li, Li; Yang, Jun; Song, Yun-Feng; Chen, Ping-Yan; Ou, Chun-Quan

    2016-05-19

    Few studies have investigated the chronic obstructive pulmonary disease (COPD) mortality fraction attributable to air pollution and modification by individual characteristics of air pollution effects. We applied distributed lag non-linear models to assess the associations between air pollution and COPD mortality in 2007-2011 in Guangzhou, China, and the total COPD mortality fraction attributable to air pollution was calculated as well. We found that an increase of 10 μg/m(3) in particulate matter with an aerodynamic diameter of 10 μm or less (PM10), sulfur dioxide (SO2) and nitrogen dioxide (NO2) was associated with a 1.58% (95% confidence interval (CI): 0.12-3.06%), 3.45% (95% CI: 1.30-5.66%) and 2.35% (95% CI: 0.42-4.32%) increase of COPD mortality over a lag of 0-15 days, respectively. Greater air pollution effects were observed in the elderly, males and residents with low educational attainment. The results showed 10.91% (95% CI: 1.02-9.58%), 12.71% (95% CI: 5.03-19.85%) and 13.38% (95% CI: 2.67-22.84%) COPD mortality was attributable to current PM10, SO2 and NO2 exposure, respectively. In conclusion, the associations between air pollution and COPD mortality differed by individual characteristics. There were remarkable COPD mortality burdens attributable to air pollution in Guangzhou.

  8. [Air Bubble in the Left Ventricle due to Computed Tomography Guided Lung Needle Biopsy].

    Science.gov (United States)

    Matsuda, Eisuke; Yoshida, Kumiko; Yoshiyama, Koichi; Hayashi, Tatsuro; Tanaka, Toshiki; Tao, Hiroyuki; Okabe, Kazunori

    2015-11-01

    Computed tomography (CT) guided lung biopsy is a useful examination in diagnosing pulmonary diseases, but the complications such as pneumothorax or pulmonary hemorrhage can not be ignored. Among them, air embolization is a severe complication, although it is infrequently encountered. Forty two-year-old man admitted to our department for the examination of left lung tumor. CT guided lung biopsy was performed. After examination, the patient showed disturbance in cardiac function, which recovered in several minutes. Chest CT revealed air bubble in the left ventricle. After 2-hours head down position followed by bed rest, air bubble is confirmed to be dissappeared by CT.

  9. Factors affecting xylene-contaminated air removal by the ornamental plant Zamioculcas zamiifolia.

    Science.gov (United States)

    Sriprapat, Wararat; Boraphech, Phattara; Thiravetyan, Paitip

    2014-02-01

    Fifteen plant species-Alternanthera bettzickiana, Drimiopsis botryoides, Aloe vera, Chlorophytum comosum, Aglaonema commutatum, Cordyline fruticosa, Philodendron martianum, Sansevieria hyacinthoides, Aglaonema rotundum, Fittonia albivenis, Muehlenbeckia platyclada, Tradescantia spathacea, Guzmania lingulata, Zamioculcas zamiifolia, and Cyperus alternifolius-were evaluated for the removal efficiency of xylene from contaminated air. Among the test plants, Z. zamiifolia showed the highest xylene removal efficiency. Xylene was toxic to Z. zamiifolia with an LC50 of 3,464 ppm. Higher concentrations of xylene exhibited damage symptoms, including leaf tips turning yellow, holonecrosis, and hydrosis. TEM images showed that a low concentration of xylene vapors caused minor changes in the chloroplast, while a high concentration caused swollen chloroplasts and damage. The effect of photosynthetic types on xylene removal efficiency suggests that a mixture of Z. zamiifolia, S. hyacinthoides, and A. commutatum which represent facultative CAM, CAM, and C3 plants, is the most suitable system for xylene removal. Therefore, for maximum improvement in removing xylene volatile compounds under various conditions, multiple species are needed. The effect of a plant's total leaf area on xylene removal indicates that at lower concentrations of xylene, a small leaf area might be as efficient as a large leaf area.

  10. Bilirubin oxidase based enzymatic air-breathing cathode: Operation under pristine and contaminated conditions.

    Science.gov (United States)

    Santoro, Carlo; Babanova, Sofia; Erable, Benjamin; Schuler, Andrew; Atanassov, Plamen

    2016-04-01

    The performance of bilirubin oxidase (BOx) based air breathing cathode was constantly monitored over 45 days. The effect of electrolyte composition on the cathode oxygen reduction reaction (ORR) output was investigated. Particularly, deactivation of the electrocatalytic activity of the enzyme in phosphate buffer saline (PBS) solution and in activated sludge (AS) was evaluated. The greatest drop in current density was observed during the first 3 days of constant operation with a decrease of ~60 μA cm(-2) day(-1). The rate of decrease slowed to ~10 μA cm(-2) day(-1) (day 3 to 9) and then to ~1.5 μA cm(-2)day(-1) thereafter (day 9 to 45). Despite the constant decrease in output, the BOx cathode generated residual current after 45 days operations with an open circuit potential (OCP) of 475 mV vs. Ag/AgCl. Enzyme deactivation was also studied in AS to simulate an environment close to the real waste operation with pollutants, solid particles and bacteria. The presence of low-molecular weight soluble contaminants was identified as the main reason for an immediate enzymatic deactivation within few hours of cathode operation. The presence of solid particles and bacteria does not affect the natural degradation of the enzyme.

  11. Contamination of indoor dust and air by polychlorinated biphenyls and brominated flame retardants and relevance of non-dietary exposure in Vietnamese informal e-waste recycling sites.

    Science.gov (United States)

    Tue, Nguyen Minh; Takahashi, Shin; Suzuki, Go; Isobe, Tomohiko; Viet, Pham Hung; Kobara, Yuso; Seike, Nobuyasu; Zhang, Gan; Sudaryanto, Agus; Tanabe, Shinsuke

    2013-01-01

    This study investigated the occurrence of polychlorinated biphenyls (PCBs), and several additive brominated flame retardants (BFRs) in indoor dust and air from two Vietnamese informal e-waste recycling sites (EWRSs) and an urban site in order to assess the relevance of these media for human exposure. The levels of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), 1,2-bis-(2,4,6-tribromophenoxy)ethane (BTBPE) and decabromodiphenyl ethane (DBDPE) in settled house dust from the EWRSs (130-12,000, 5.4-400, 5.2-620 and 31-1400 ng g(-1), respectively) were significantly higher than in urban house dust but the levels of PCBs (4.8-320 ng g(-1)) were not higher. The levels of PCBs and PBDEs in air at e-waste recycling houses (1000-1800 and 620-720 pg m(-3), respectively), determined using passive sampling, were also higher compared with non-e-waste houses. The composition of BFRs in EWRS samples suggests the influence from high-temperature processes and occurrence of waste materials containing older BFR formulations. Results of daily intake estimation for e-waste recycling workers are in good agreement with the accumulation patterns previously observed in human milk and indicate that dust ingestion contributes a large portion of the PBDE intake (60%-88%), and air inhalation to the low-chlorinated PCB intake (>80% for triCBs) due to their high levels in dust and air, respectively. Further investigation of both indoor dust and air as the exposure media for other e-waste recycling-related contaminants and assessment of health risk associated with exposure to these contaminant mixtures is necessary.

  12. Prediction and mitigation of air preheater fouling due to ammonium bisulfate

    Energy Technology Data Exchange (ETDEWEB)

    Afonso, R.; Tavoulareas, S.; Stallings, J. [Energy and Environmental Strategies, MA (United States)

    2001-07-01

    This paper provides a brief review of the fundamentals of ammonium bisulfate (ABS) formation, deposition and fouling in the air preheater. It presents a software-based predictive model for assessing the potential for air preheater fouling as a result of proposed SNCR or SCR retrofits and considering site-specific conditions and introduces a software-based cost-benefit model for assessing the economic trade-offs of various ABS fouling mitigation options. 7 refs., 13 figs.

  13. Numerical Simulation of Inter-Flat Air Cross-Contamination under the Condition of Single-Sided Natural Ventilation

    DEFF Research Database (Denmark)

    Liu, Xiaoping; Niu, Jianlei; Perino, Marco;

    2008-01-01

    the two sides, each of which has a flat fa ade with openable windows. When the wind speed is extremely low, with doors closed and windows opened, the flats become single-sided naturally ventilated driven by buoyancy effects. The air pollutants can travel from a lower flat to a vertically adjacent upper...... flat through open windows, caused by indoor/outdoor temperature-difference induced buoyancy. Computational fluid dynamics is employed to explore the characteristics of this process. Based on the comparison with experimental data about the air flow distribution in and around a single-sided naturally...... be a major route of the air cross-contamination in high-rise residential buildings. Finally, an assessment index is proposed to evaluate the potential infection risks associated with this inter-flat air flow occurring in high-rise residential buildings....

  14. Population exposure to hazardous air quality due to the 2015 fires in Equatorial Asia

    Science.gov (United States)

    Crippa, P.; Castruccio, S.; Archer-Nicholls, S.; Lebron, G. B.; Kuwata, M.; Thota, A.; Sumin, S.; Butt, E.; Wiedinmyer, C.; Spracklen, D. V.

    2016-11-01

    Vegetation and peatland fires cause poor air quality and thousands of premature deaths across densely populated regions in Equatorial Asia. Strong El-Niño and positive Indian Ocean Dipole conditions are associated with an increase in the frequency and intensity of wildfires in Indonesia and Borneo, enhancing population exposure to hazardous concentrations of smoke and air pollutants. Here we investigate the impact on air quality and population exposure of wildfires in Equatorial Asia during Fall 2015, which were the largest over the past two decades. We performed high-resolution simulations using the Weather Research and Forecasting model with Chemistry based on a new fire emission product. The model captures the spatio-temporal variability of extreme pollution episodes relative to space- and ground-based observations and allows for identification of pollution sources and transport over Equatorial Asia. We calculate that high particulate matter concentrations from fires during Fall 2015 were responsible for persistent exposure of 69 million people to unhealthy air quality conditions. Short-term exposure to this pollution may have caused 11,880 (6,153–17,270) excess mortalities. Results from this research provide decision-relevant information to policy makers regarding the impact of land use changes and human driven deforestation on fire frequency and population exposure to degraded air quality.

  15. Dynamic water behaviour due to one trapped air pocket in a laboratory pipeline apparatus

    Science.gov (United States)

    Bergant, A.; Karadžić, U.; Tijsseling, A.

    2016-11-01

    Trapped air pockets may cause severe operational problems in hydropower and water supply systems. A locally isolated air pocket creates distinct amplitude, shape and timing of pressure pulses. This paper investigates dynamic behaviour of a single trapped air pocket. The air pocket is incorporated as a boundary condition into the discrete gas cavity model (DGCM). DGCM allows small gas cavities to form at computational sections in the method of characteristics (MOC). The growth of the pocket and gas cavities is described by the water hammer compatibility equation(s), the continuity equation for the cavity volume, and the equation of state of an ideal gas. Isentropic behaviour is assumed for the trapped gas pocket and an isothermal bath for small gas cavities. Experimental investigations have been performed in a laboratory pipeline apparatus. The apparatus consists of an upstream end high-pressure tank, a horizontal steel pipeline (total length 55.37 m, inner diameter 18 mm), four valve units positioned along the pipeline including the end points, and a downstream end tank. A trapped air pocket is captured between two ball valves at the downstream end of the pipeline. The transient event is initiated by rapid opening of the upstream end valve; the downstream end valve stays closed during the event. Predicted and measured results for a few typical cases are compared and discussed.

  16. Watching the wind: seismic data contamination at long-periods due to atmospheric pressure-field-induced tilting

    Science.gov (United States)

    de Angelis, S.; Bodin, P.; Hagel, K.; Fletcher, D.

    2010-12-01

    Long-period noise generated by the elastic response of the Earth to atmospheric pressure fluctuations has long been recognized as a limiting factor for seismic investigations. The quality of seismic data recorded by sensitive, near-surface broadband seismometers can be severely corrupted by this effect. During the recent installation of a new broadband site on the Olympic Peninsula in Washington, the Pacific Northwest Seismic Network recorded and investigated elevated daytime noise levels at periods exceeding 30 seconds. Substantial power spectral density variations of the background noise field, 15-20 dB, were observed in the horizontal component seismograms. The pattern of the long-period noise exhibited striking correlations with local fluctuations of the air temperature and wind speed as measured nearby the seismic station by the National Weather Service Forecast Office, Seattle, Washington, and the National Oceanic and Atmospheric Administration. Several past studies have demonstrated that local wind systems may lead to variations of the atmospheric pressure field that deform the ground and perturb seismograms. The rotational component of this motion is detected by horizontal-component seismometers because at periods longer than the sensor’s low corner frequency the sensor is acting essentially as a tiltmeter. We obtained a transfer function that describes the response of the broadband seismometer to a tilt step change and estimated the amplitude of tilt noise to be on the order of 10-9 - 10-8 radians. Within the seismic pass-band of the sensor, it is not possible to remove the tilt signal from the observed seismograms because the details of the tilting depend on the pressure field variations, the compliance of the near surface to pressure variations, and the design and construction of the seismometer vault itself. At longer periods, using the seismic data to recover tilts of tectonic origin is made challenging because of the needed instrument correction

  17. Sub-soil contamination due to oil spills in zones surrounding oil pipeline-pump stations and oil pipeline right-of-ways in Southwest-Mexico.

    Science.gov (United States)

    Iturbe, Rosario; Flores, Carlos; Castro, Alejandrina; Torres, Luis G

    2007-10-01

    Oil spills due to oil pipelines is a very frequent problem in Mexico. Petroleos Mexicanos (PEMEX), very concerned with the environmental agenda, has been developing inspection and correction plans for zones around oil pipelines pumping stations and pipeline right-of-way. These stations are located at regular intervals of kilometres along the pipelines. In this study, two sections of an oil pipeline and two pipeline pumping stations zones are characterized in terms of the presence of Total Petroleum Hydrocarbons (TPHs) and Polycyclic Aromatic Hydrocarbons (PAHs). The study comprehends sampling of the areas, delimitation of contamination in the vertical and horizontal extension, analysis of the sampled soils regarding TPHs content and, in some cases, the 16 PAHs considered as priority by USEPA, calculation of areas and volumes contaminated (according to Mexican legislation, specifically NOM-EM-138-ECOL-2002) and, finally, a proposal for the best remediation techniques suitable for the contamination levels and the localization of contaminants.

  18. Enhancement of the radar signal of air showers due to time compression

    CERN Document Server

    Stasielak, J; Engel, R; Neunteufel, P; Pekala, J; Šm\\'\\ida, R; Werner, F; Wilczyński, H

    2013-01-01

    We investigate the feasibility of detecting extensive air showers by the radar technique at viewing angles smaller than $\\sim 25^\\circ$ to the shower axis. Considering a bistatic radar setup and shower geometries in which the receiver points into the arriving shower, we simulate reflection of radio waves off the short-lived plasma produced by the high-energy shower particles in the air. Using the Thomson cross-section for scattering of radio waves and summing coherently contributions of the reflected radio wave over the volume of the plasma disk, we obtain the time evolution of the signal. We analyze the spectral power density of the radar echo and the received power. Based on the obtained results, we discuss possible modes of the radar detection of extensive air showers.

  19. CAirTOX, An inter-media transfer model for assessing indirect exposures to hazardous air contaminants

    Energy Technology Data Exchange (ETDEWEB)

    McKone, T.E.

    1994-01-01

    Risk assessment is a quantitative evaluation of information on potential health hazards of environmental contaminants and the extent of human exposure to these contaminants. As applied to toxic chemical emissions to air, risk assessment involves four interrelated steps. These are (1) determination of source concentrations or emission characteristics, (2) exposure assessment, (3) toxicity assessment, and (4) risk characterization. These steps can be carried out with assistance from analytical models in order to estimate the potential risk associated with existing and future releases. CAirTOX has been developed as a spreadsheet model to assist in making these types of calculations. CAirTOX follows an approach that has been incorporated into the CalTOX model, which was developed for the California Department of Toxic Substances Control, With CAirTOX, we can address how contaminants released to an air basin can lead to contamination of soil, food, surface water, and sediments. The modeling effort includes a multimedia transport and transformation model, exposure scenario models, and efforts to quantify uncertainty in multimedia, multiple-pathway exposure assessments. The capacity to explicitly address uncertainty has been incorporated into the model in two ways. First, the spreadsheet form of the model makes it compatible with Monte-Carlo add-on programs that are available for uncertainty analysis. Second, all model inputs are specified in terms of an arithmetic mean and coefficient of variation so that uncertainty analyses can be carried out.

  20. Effects of walk-by and sash movement on contaminant leakage of air curtain-isolated fume hood.

    Science.gov (United States)

    Huang, Rong Fung; Chen, Hong Da; Hung, Chien-Hsiung

    2007-12-01

    The effects of the walk-by motion and sash movement on the containment leakage of an air curtain-isolated fume hood were evaluated and compared with the results of a corresponding conventional fume hood. The air curtain was generated by a narrow planar jet issued from the double-layered sash and a suction slot-flow arranged on the floor of the hood just behind the doorsill. The conventional fume hood used for comparison had the major dimensions identical to the air-curtain hood. SF tracer-gas concentrations were released and measured following the prEN 14175-3:2003 protocol to examine the contaminant leakage levels. Experimental results showed that operating the air-curtain hood at the suction velocity above about 6 m/s and jet velocity about 1 m/s could provide drastically high containment performance when compared with the corresponding conventional fume hood operated at the face velocity of 0.5 m/s. The total air flow required for the air-curtain hood operated at 6 m/s suction velocity and 1 m/s jet velocity was about 20% less than that exhausted by the conventional fume hood. If the suction velocity of the air-curtain hood was increased above 8 m/s, the containment leakage during dynamic motions could be reduced to ignorable level (about 10(3) ppm).

  1. Risk assessment for cardiovascular and respiratory mortality due to air pollution and synoptic meteorology in 10 Canadian cities.

    Science.gov (United States)

    Vanos, Jennifer K; Hebbern, Christopher; Cakmak, Sabit

    2014-02-01

    Synoptic weather and ambient air quality synergistically influence human health. We report the relative risk of mortality from all non-accidental, respiratory-, and cardiovascular-related causes, associated with exposure to four air pollutants, by weather type and season, in 10 major Canadian cities for 1981 through 1999. We conducted this multi-city time-series study using Poisson generalized linear models stratified by season and each of six distinctive synoptic weather types. Statistically significant relationships of mortality due to short-term exposure to carbon monoxide, nitrogen dioxide, sulphur dioxide, and ozone were found, with significant modifications of risk by weather type, season, and mortality cause. In total, 61% of the respiratory-related mortality relative risk estimates were significantly higher than for cardiovascular-related mortality. The combined effect of weather and air pollution is greatest when tropical-type weather is present in the spring or summer.

  2. Direct quantitative analysis of phthalate esters as micro-contaminants in cleanroom air and wafer surfaces by auto-thermal desorption--gas chromatography--mass spectrometry.

    Science.gov (United States)

    Kang, Yuhao; Den, Walter; Bai, Hsunling; Ko, Fu-Hsiang

    2005-04-01

    This study established an analytical method for the trace analyses of two phthalate esters, including diethyl phthalate (DEP) and di-n-butyl phthalate (DBP), known as the major constituents of cleanroom micro-contamination detrimental to the reliability of semiconductor devices. Using thermal desorption coupled with a GC-MS system, standard tubes were prepared by delivering liquid standards pre-vaporized by a quasi-vaporizer into Tenax GR tubes for calibration. This method was capable of achieving detection limits of 0.05 microg m(-3) for 0.1 m3 air samples and 0.03 ng cm(-2) for 150-mm wafer surface density. Actual samples collected from a semiconductor cleanroom showed that the concentration of DBP in a polypropylene wafer box (0.45 microg m(-3)) was nearly four times higher than that in the cleanroom environment (0.12 microg m(-3)). The surface contamination of DBP was 0.67 ng cm(-2) for a wafer stored in the wafer box for 24 h. Furthermore, among the three types of heat-resistant O-ring materials tested, Kalrez was found to be particularly suitable for high-temperature processes in semiconductor cleanrooms due to their low emissions of organic vapors. This analytical procedure should serve as an effective monitoring method for the organic micro-contamination in cleanroom environments.

  3. Model calculated global, regional and megacity premature mortality due to air pollution

    Directory of Open Access Journals (Sweden)

    J. Lelieveld

    2013-03-01

    Full Text Available Air pollution by fine particulate matter (PM2.5 and ozone (O3 has increased strongly with industrialization and urbanization. We estimated the premature mortality rates and the years of human life lost (YLL caused by anthropogenic PM2.5 and O3 in 2005 for epidemiological regions defined by the World Health Organization. We carried out high-resolution global model calculations to resolve urban and industrial regions in greater detail compared to previous work. We applied a health impact function to estimate premature mortality for people of 30 yr and older, using parameters derived from epidemiological cohort studies. Our results suggest that especially in large countries with extensive suburban and rural populations, air pollution-induced mortality rates have previously been underestimated. We calculate a global respiratory mortality of about 773 thousand yr−1 (YLL ≈ 5.2 million yr−1, 186 thousand yr−1 by lung cancer (YLL ≈ 1.7 million yr−1 and 2.0 million yr−1 by cardiovascular disease (YLL ≈ 14.3 million yr−1. The global mean per capita mortality caused by air pollution is about 0.1 % yr−1. The highest premature mortality rates are found in the Southeast Asia and Western Pacific regions (about 25% and 46% of the global rate, respectively where more than a dozen of the most highly polluted megacities are located.

  4. A method to correct IACT data for atmospheric absorption due to the Saharan Air Layer

    CERN Document Server

    Dorner, Daniela; Bretz, Thomas

    2008-01-01

    Using the atmosphere as a detector volume, Imaging Air Cherenkov Telescopes (IACTs) depend highly on the properties and the condition of the air mass above the telescope. On the Canary Island of La Palma, where the Major Atmospheric Gamma-ray Imaging Cherenkov telescope (MAGIC) is situated, the Saharan Air Layer (SAL) can cause strong atmospheric absorption affecting the data quality and resulting in a reduced gamma flux. To correlate IACT data with other measurements, e.g. long-term monitoring or Multi-Wavelength (MWL) studies, an accurate flux determination is mandatory. Therefore, a method to correct the data for the effect of the SAL is needed. Three different measurements of the atmospheric absorption are performed on La Palma. From the determined transmission, a correction factor is calculated and applied to the MAGIC data. The different transmission measurements from optical and IACT data provide comparable results. MAGIC data of PG 1553+113, taken during a MWL campaign in July 2006, have been analyzed...

  5. Coal mining activities change plant community structure due to air pollution and soil degradation.

    Science.gov (United States)

    Pandey, Bhanu; Agrawal, Madhoolika; Singh, Siddharth

    2014-10-01

    The aim of this study was to investigate the effects of coal mining activities on the community structures of woody and herbaceous plants. The response of individual plants of community to defilement caused by coal mining was also assessed. Air monitoring, soil physico-chemical and phytosociological analyses were carried around Jharia coalfield (JCF) and Raniganj coalfield. The importance value index of sensitive species minified and those of tolerant species enhanced with increasing pollution load and altered soil quality around coal mining areas. Although the species richness of woody and herbaceous plants decreased with higher pollution load, a large number of species acclimatized to the stress caused by the coal mining activities. Woody plant community at JCF was more affected by coal mining than herbaceous community. Canonical correspondence analysis revealed that structure of herbaceous community was mainly driven by soil total organic carbon, soil nitrogen, whereas woody layer community was influenced by sulphur dioxide in ambient air, soil sulphate and soil phosphorus. The changes in species diversity observed at mining areas indicated an increase in the proportion of resistant herbs and grasses showing a tendency towards a definite selection strategy of ecosystem in response to air pollution and altered soil characteristics.

  6. Is mudflow in Sidoarjo, East Java due to the pumping mechanism of hot air bubbles? : Laboratory simulations and field observations

    Science.gov (United States)

    Nurhandoko, Bagus Endar B.

    2015-09-01

    Extraordinary mudflow has happened in Sidoarjo, East Java, Indonesia since 2006. This mud comes from the giant crater that is located close to the BJP - 01. Thousands of homes have been submerged due to mudflow. Till today this giant mud crater is still has great strength despite the mud flowing over 8 years. This is a very rare phenomenon in the world. This mud flow mechanism raises big questions, because it has been going on for years, naturally the mudflow will stop by itself because the pressure should be reduced. This research evaluates all aspects of integrated observations, laboratory tests and field observations since the beginning of this ongoing mudflow. Laboratory tests were done by providing hot air bubbles into the fluid inside the inverted funnel showed that the fluid can flow with a high altitude. It is due to the mechanism of buoyant force from air bubbles to the water where the contrast density of the water and the air is quite large. Quantity of air bubbles provides direct effect to the debit of fluid flow. Direct observation in the field, in 2006 and 2007, with TIMNAS and LPPM ITB showed the large number of air bubbles on the surface of the mud craters. Temperature observation on the surface of mud crater is around 98 degree C whereas at greater depth shows the temperature is increasingly rising. This strengthens the hypothesis or proves that the mud pumping mechanism comes from buoyant force of hot air bubbles. Inversion gravity images show that the deep subsurface of main crater is close to volcanic layers or root of Arjuna mountain. Based on the simulation laboratory and field observation data, it can be concluded that the geothermal factor plays a key role in the mudflow mechanism.

  7. Multimodel estimates of premature human mortality due to intercontinental transport of air pollution

    Science.gov (United States)

    Liang, C.; Silva, R.; West, J. J.; Sudo, K.; Lund, M. T.; Emmons, L. K.; Takemura, T.; Bian, H.

    2015-12-01

    Numerous modeling studies indicate that emissions from one continent influence air quality over others. Reducing air pollutant emissions from one continent can therefore benefit air quality and health on multiple continents. Here, we estimate the impacts of the intercontinental transport of ozone (O3) and fine particulate matter (PM2.5) on premature human mortality by using an ensemble of global chemical transport models coordinated by the Task Force on Hemispheric Transport of Air Pollution (TF HTAP). We use simulations of 20% reductions of all anthropogenic emissions from 13 regions (North America, Central America, South America, Europe, Northern Africa, Sub-Saharan Africa, Former Soviet Union, Middle East, East Asia, South Asia, South East Asia, Central Asia, and Australia) to calculate their impact on premature mortality within each region and elsewhere in the world. To better understand the impact of potential control strategies, we also analyze premature mortality for global 20% perturbations from five sectors individually: power and industry, ground transport, forest and savannah fires, residential, and others (shipping, aviation, and agriculture). Following previous studies, premature human mortality resulting from each perturbation scenario is calculated using a health impact function based on a log-linear model for O3 and an integrated exposure response model for PM2.5 to estimate relative risk. The spatial distribution of the exposed population (adults aged 25 and over) is obtained from the LandScan 2011 Global Population Dataset. Baseline mortality rates for chronic respiratory disease, ischemic heart disease, cerebrovascular disease, chronic obstructive pulmonary disease, and lung cancer are estimated from the GBD 2010 country-level mortality dataset for the exposed population. Model results are regridded from each model's original grid to a common 0.5°x0.5° grid used to estimate mortality. We perform uncertainty analysis and evaluate the sensitivity

  8. Does the soil-air-plant pathway contribute to the PCB contamination of apples from allotment gardens?

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, M.; Moering, J.; Amelung, W. [Dept. of Soil Science, Inst. of Ecology, Berlin Univ. of Tech. (Germany)

    2004-09-15

    The presence of persistent organic pollutants (POPs) like PCBs in plants poses a risk to humans and animals as it determines an exposure through the terrestrial food chain. A number of studies have shown that the transfer from the atmosphere is the dominant pathway for an uptake of POPs by aboveground parts of plants, in which dry gaseous as well as wet and dry particulate deposition are involved. The relative contribution of the different pathways to the overall deposition depends strongly on the physical-chemical properties of the compounds, but also on microclimatic conditions and characteristics of the plant, which both contribute to diffusive resistance at the its surface. In contrast, root uptake and translocation in the shoot is probably much less important for these highly hydrophobic compounds, although there are contradicting results in the literature. While the air-plant distribution of POPs received increasing attention, the importance of the soilair- plant pathway has rarely been studied. It is not known whether the volatilisation of POPs from contaminated soils and subsequent deposition to plants may be a significant source compared to ''background'' deposition in the field, as well as a deposition of contaminated soil dust raised by wind or rain splash. Particularly the latter pathway can hardly be assessed under exposure chamber conditions; instead a field study is required despite the increased overall complexity, which renders process identification more difficult. The objective of our study was to assess whether the local soil contamination (soil-air-plant pathway) could contribute to the PCB contamination of apples (Malus domestica Borkh.) at an allotment garden site additionally to background deposition (air-plant pathway).

  9. Air sampling procedures to evaluate microbial contamination: a comparison between active and passive methods in operating theatres

    Directory of Open Access Journals (Sweden)

    Napoli Christian

    2012-08-01

    Full Text Available Abstract Background Since air can play a central role as a reservoir for microorganisms, in controlled environments such as operating theatres regular microbial monitoring is useful to measure air quality and identify critical situations. The aim of this study is to assess microbial contamination levels in operating theatres using both an active and a passive sampling method and then to assess if there is a correlation between the results of the two different sampling methods. Methods The study was performed in 32 turbulent air flow operating theatres of a University Hospital in Southern Italy. Active sampling was carried out using the Surface Air System and passive sampling with settle plates, in accordance with ISO 14698. The Total Viable Count (TVC was evaluated at rest (in the morning before the beginning of surgical activity and in operational (during surgery. Results The mean TVC at rest was 12.4 CFU/m3 and 722.5 CFU/m2/h for active and passive samplings respectively. The mean in operational TVC was 93.8 CFU/m3 (SD = 52.69; range = 22-256 and 10496.5 CFU/m2/h (SD = 7460.5; range = 1415.5-25479.7 for active and passive samplings respectively. Statistical analysis confirmed that the two methods correlate in a comparable way with the quality of air. Conclusion It is possible to conclude that both methods can be used for general monitoring of air contamination, such as routine surveillance programs. However, the choice must be made between one or the other to obtain specific information.

  10. The Contaminant Distribution in a Ventilated Room with Different Air Terminal Devices

    DEFF Research Database (Denmark)

    Heiselberg, Per; Nielsen, Peter V.

    of the jets and the comfort requirements applied to measured air velocities in the occupied zone. Normalized concentration distribution in the test room is determined along a vertical line through the middle of the room as a function of the air exchange rate and the density of the tracer gas. The relative......The room ventilation is investigated for three different air terminal devices under isothermal conditions. Velocity distribution in the occupied zone is measured for each air terminal device at different air exchange rates. The maximum air exchange rate is determined on the base of both the throw...... ventilation efficiency, , based on the room average concentration is also determined as a function of the air exchange rate and the density of the tracer gas. The influence from the position of the return opening on the relative ventilation efficiency is found for one air terminal device....

  11. Nitric Oxide and Oxygen Air-Contamination Effects on Extinction Limits of Non-Premixed Hydrocarbon-Air Flames for a HIFiRE Scramjet

    Science.gov (United States)

    Pellett, Gerald L.; Dawson, Lucy C.; Vaden, Sarah N.; Wilson, Lloyd G.

    2009-01-01

    Unique nitric oxide (NO) and oxygen air-contamination effects on the extinction Flame Strength (FS) of non-premixed hydrocarbon (HC) vs. air flames are characterized for 7 gaseous HCs, using a new idealized 9.3 mm straight-tube Opposed Jet Burner (OJB) at 1 atm. FS represents a laminar strain-induced extinction limit based on cross-section-average air jet velocity, Uair, that sustains combustion of a counter jet of gaseous fuel just before extinction. Besides ethane, propane, butane, and propylene, the HCs include ethylene, methane, and a 64 mole-% ethylene / 36 % methane mixture, the writer s previously recommended gaseous surrogate fuel for HIFiRE scramjet tests. The HC vs. clean air part of the work is an extension of a May 2008 JANNAF paper that characterized surrogates for the HIFiRE project that should mimic the flameholding of reformed (thermally- or catalytically-cracked) endothermic JP-like fuels. The new FS data for 7 HCs vs. clean air are thus consolidated with the previously validated data, normalized to absolute (local) axial-input strain rates, and co-plotted on a dual kinetically dominated reactivity scale. Excellent agreement with the prior data is obtained for all 7 fuels. Detailed comparisons are also made with recently published (Univ. Va) numerical results for ethylene extinction. A 2009-revised ethylene kinetic model (Univ. Southern Cal) led to predicted limits within approx. 5 % (compared to 45 %, earlier) of this writer s 2008 (and present) ethylene FSs, and also with recent independent data (Univ. Va) obtained on a new OJB system. These +/- 5 % agreements, and a hoped-for "near-identically-performing" reduced kinetics model, would greatly enhance the capability for accurate numerical simulations of surrogate HC flameholding in scramjets. The measured air-contamination effects on normalized FS extinction limits are projected to assess ongoing Arc-Heater-induced "facility test effects" of NO production (e.g., 3 mole-%) and resultant oxygen

  12. Model calculated global, regional and megacity premature mortality due to air pollution

    Science.gov (United States)

    Lelieveld, J.; Barlas, C.; Giannadaki, D.; Pozzer, A.

    2013-07-01

    Air pollution by fine particulate matter (PM2.5) and ozone (O3) has increased strongly with industrialization and urbanization. We estimate the premature mortality rates and the years of human life lost (YLL) caused by anthropogenic PM2.5 and O3 in 2005 for epidemiological regions defined by the World Health Organization (WHO). This is based upon high-resolution global model calculations that resolve urban and industrial regions in greater detail compared to previous work. Results indicate that 69% of the global population is exposed to an annual mean anthropogenic PM2.5 concentration of >10 μg m-3 (WHO guideline) and 33% to > 25 μg m-3 (EU directive). We applied an epidemiological health impact function and find that especially in large countries with extensive suburban and rural populations, air pollution-induced mortality rates have been underestimated given that previous studies largely focused on the urban environment. We calculate a global respiratory mortality of about 773 thousand/year (YLL ≈ 5.2 million/year), 186 thousand/year by lung cancer (YLL ≈ 1.7 million/year) and 2.0 million/year by cardiovascular disease (YLL ≈ 14.3 million/year). The global mean per capita mortality caused by air pollution is about 0.1% yr-1. The highest premature mortality rates are found in the Southeast Asia and Western Pacific regions (about 25% and 46% of the global rate, respectively) where more than a dozen of the most highly polluted megacities are located.

  13. Model calculated global, regional and megacity premature mortality due to air pollution

    Directory of Open Access Journals (Sweden)

    J. Lelieveld

    2013-07-01

    Full Text Available Air pollution by fine particulate matter (PM2.5 and ozone (O3 has increased strongly with industrialization and urbanization. We estimate the premature mortality rates and the years of human life lost (YLL caused by anthropogenic PM2.5 and O3 in 2005 for epidemiological regions defined by the World Health Organization (WHO. This is based upon high-resolution global model calculations that resolve urban and industrial regions in greater detail compared to previous work. Results indicate that 69% of the global population is exposed to an annual mean anthropogenic PM2.5 concentration of >10 μg m−3 (WHO guideline and 33% to > 25 μg m−3 (EU directive. We applied an epidemiological health impact function and find that especially in large countries with extensive suburban and rural populations, air pollution-induced mortality rates have been underestimated given that previous studies largely focused on the urban environment. We calculate a global respiratory mortality of about 773 thousand/year (YLL ≈ 5.2 million/year, 186 thousand/year by lung cancer (YLL ≈ 1.7 million/year and 2.0 million/year by cardiovascular disease (YLL ≈ 14.3 million/year. The global mean per capita mortality caused by air pollution is about 0.1% yr−1. The highest premature mortality rates are found in the Southeast Asia and Western Pacific regions (about 25% and 46% of the global rate, respectively where more than a dozen of the most highly polluted megacities are located.

  14. Sub-soil contamination due to oil spills in six oil-pipeline pumping stations in northern Mexico.

    Science.gov (United States)

    Iturbe, Rosario; Flores, Carlos; Castro, Alejandrina; Torres, Luis G

    2007-06-01

    Mexico has a very important oil industry, comprehending the exploration, production, transformation, storage and distribution of crude oil and its fractions. Petroleos Mexicanos (PEMEX) is a state-owned monopoly in charge of these activities. Oil and oil-products transport is an extremely crucial operation for the cycle production-transformation-distribution. Pipeline system transport crude oil and sub-products along the country (including liquids, gases and mixtures). It has been reported that more than 30% of the oil ducts in Mexico have been operating for over 30 years, although their lifetime has been calculated in 25-30 years. This work is aimed at characterizing a zone around six oil-pipeline pumping stations located at northern Mexico. The specific places to evaluate soil contamination were (1) the distribution head of the Gomez Palacio (GOPA) pumping station; (2) the north side of the old ditch, the API oil separator and the wastewater zones of the Jimenez (JIM) pumping station; (3) the pumping stations of Ceballos (CE), Peronal (PER), Simon Bolivar (SIBO), and Mayran (MAY). The study comprehended sampling of the areas, delimitation of contamination in the vertical and horizontal extension, analysis of the sampled soils, regarding TPH and, in some cases, the 16 PAHs considered as a priority by USEPA, calculation of areas and volumes contaminated (according to the Mexican legislation, specifically NOM-EM-138-ECOL-2002) and, finally, a proposal for the best remediation techniques suitable for the encountered contamination levels and the localization of contaminants. In general, TPHs were found in all the pumping stations analyzed in this study. Regarding maximal TPHs concentrations at the stations, their order of contamination was as follows: SIBO>CE>PER>MAY>JIM>GOPA. PAHs were found only in a few points at concentrations above the detection limit. At the Jimenez, Gomez Palacio, Peronal, and Ceballos stations, only one point, with PAHs values over the

  15. Long-Term Prospective Study of 6104 Survivors of Arsenic Poisoning During Infancy Due to Contaminated Milk Powder in 1955

    OpenAIRE

    Tanaka, Hideo; Tsukuma, Hideaki; Oshima, Akira

    2010-01-01

    Background In 1955, an outbreak of arsenic poisoning caused by ingestion of arsenic-contaminated dry milk occurred in western Japan. We assessed the excess mortality among Japanese who were poisoned during this episode as infants. Methods We identified and enrolled 6104 survivors (mean age at enrollment, 27.4 years) who had ingested contaminated milk when they were age 2 years or younger; they were followed until 2006 (mean duration of follow-up, 24.3 years). Death certificates of subjects wh...

  16. [Air pollution due to the burning of thermoplastics II (author's transl)].

    Science.gov (United States)

    van Grimbergen, M; Reybrouck, G; van de Voorde, H

    1975-03-01

    Following on from the first publication, (12) concerning the burning of plastics, another 13 chemical pure polymers were burnt in an electric oven to determine the level of solid and gaseous air pollution caused by their stackgases. All 13 polymers are highly combustible but require different burning temperatures (300-900 degrees C) in order to be burnt completely (i.e. without ashrest). With the exception of PMMA and PTFE, all plastics leave a very heavy tar- and soot deposit after burning. At the other end of the scale, burning at low temperature (300 degrees C) gives rise to high concentrations of alipathic aldehyds. The pH of the exhaust-gases, dissolved in water, is neutral to strong acid (PTFE), and will cause a severe corrosion. The nitrogen-containing polymers pollute by forming cyanides, nitrogenoxides and ammonia. PTFE gives off high concentrations of fluorid into the air. PMMA decomposes in its monomer methylmethacrylate and forms large amounts of aliphatic aldehyds. ABS and SBR cause a styrene pollution.

  17. Soil Contamination due to E-Waste Disposal and Recycling Activities: A Review with Special Focus on China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei-Hua; WU Ying-Xin; M. O. SIMONNOT

    2012-01-01

    This paper presents a review of soil contamination resulting from e-waste recycling activities,with a special focus on China,where many data have been collected for a decade.Soils in the e-waste areas are often contaminated by heavy metals and organic compounds,mainly polycyclic aromatic hydrocarbons (PAHs),polybrominated diphenyl ethers (PBDEs),polychlorinated and polybrominated biphenyls (PCBs and PBBs),dechlorane plus (DP),hexabromocyclododecanes (HBCDs),polychlorinated and polybrominated dibenzop-dioxins (PCDDs and PBDDs),and polychlorinated and polybrominated dibenzofurans (PCDFs and PBDFs),while other compounds,not systematically monitored,can be found as well Pollutants are generally present in mixtures,so pollution situations are complex and diversified with a gradient of contamination from agricultural soils to hot spots at e-waste sites and mainly in open burning areas.It has been proved that pollutants were transferred to the food chain via rice in China,and that the population was threatened since high levels of various pollutants were detected in blood,placentas,hair,etc.,of residents of e-waste sites.Eventually,soil remediation techniques are reviewed.Although there are many available techniques devoted to heavy metals and persistent organic pollutants,the current techniques for the e-waste sites,where these contaminants coexist,are very sparse.Phytoremediation has been investigated and co-cropping appears as a promising approach for the slightly contaminated agricultural soils.In some cases,different remediation techniques should be combined or trained,while the influence of coexisting contaminants and the removal sequence of contaminants should be considered.In hot spots,physical and chemical techniques should be used to reduce high pollution levels to prevent further pollutant dissemination.This review highlights the urgent needs for 1) characterization of pollution status in all the countries where e-wastes are recycled,2) research on fate and

  18. Groundwater Contamination Due to Activities of an Intensive Hog Farming Operation Located on a Geologic Fault in East Mediterranean: A Study on COD, BOD₅ and Microbial Load.

    Science.gov (United States)

    Michalopoulos, Charalampos; Tzamtzis, Nikolaos; Liodakis, Stylianos

    2016-02-01

    The application of treated animal wastewater produced in intensive fog farming operations (IHFOs) on surface soil, leads to groundwater contamination. In this study, the contamination of a Mediterranean aquifer caused by long-term application of treated wastewater, produced by an IHFO, on a plot with a geologic fault within the IHFO boundaries, was investigated. Groundwater samples were taken from monitoring wells close to the IHFO. A significant increase of chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total viable count (TVC) and total coliform (TC) concentrations was found in wells, compared to control monitoring well, which were mainly affected by the subsurface flow of contaminated water, due to the presence of the geologic fault. During the winter, significant increases in concentrations of COD, BOD5, TVC and TC were noted and attributed to increased precipitation, which assisted in the accelerated transport of organic compounds and microbial load, through geologic fault, to groundwater.

  19. Climate forcing and air quality change due to regional emissions reductions by economic sector

    Directory of Open Access Journals (Sweden)

    D. Shindell

    2008-06-01

    Full Text Available We examine the air quality (AQ and radiative forcing (RF response to emissions reductions by economic sector for North America and developing Asia in the CAM and GISS composition/climate models. Decreases in annual average surface particulate are relatively robust, with intermodel variations in magnitude typically <30% and very similar spatial structure. Surface ozone responses are small and highly model dependent. The largest net RF results from reductions in emissions from the North America industrial/power and developing Asia domestic fuel burning sectors. Sulfate reductions dominate the first case, for which intermodel variations in the sulfate (or total aerosol optical depth (AOD responses are ~30% and the modeled spatial patterns of the AOD reductions are highly correlated (R=0.9. Decreases in BC dominate the developing Asia domestic fuel burning case, and show substantially greater model-to-model differences. Intermodel variations in tropospheric ozone burdens are also large, though aerosol changes dominate those cases with substantial net climate forcing. The results indicate that across-the-board emissions reductions in domestic fuel burning in developing Asia and in surface transportation in North America are likely to offer the greatest potential for substantial, simultaneous improvement in local air quality and near-term mitigation of global climate change via short-lived species. Conversely, reductions in industrial/power emissions have the potential to accelerate near-term warming, though they would improve AQ and have a long-term cooling effect on climate. These broad conclusions appear robust to intermodel differences.

  20. Applicability of the environmental relative moldiness index for quantification of residential mold contamination in an air pollution health effects study.

    Science.gov (United States)

    Kamal, Ali; Burke, Janet; Vesper, Stephen; Batterman, Stuart; Vette, Alan; Godwin, Christopher; Chavez-Camarena, Marina; Norris, Gary

    2014-01-01

    The Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS) investigated the impact of exposure to traffic-related air pollution on the respiratory health of asthmatic children in Detroit, Michigan. Since indoor mold exposure may also contribute to asthma, floor dust samples were collected in participants homes (n = 112) to assess mold contamination using the Environmental Relative Moldiness Index (ERMI). The repeatability of the ERMI over time, as well as ERMI differences between rooms and dust collection methods, was evaluated for insights into the application of the ERMI metric. ERMI values for the standard settled floor dust samples had a mean ± standard deviation of 14.5 ± 7.9, indicating high levels of mold contamination. ERMI values for samples collected from the same home 1 to 7 months apart (n = 52) were consistent and without systematic bias. ERMI values for separate bedroom and living room samples were highly correlated (r = 0.69, n = 66). Vacuum bag dust ERMI values were lower than for floor dust but correlated (r = 0.58, n = 28). These results support the use of the ERMI to evaluate residential mold exposure as a confounder in air pollution health effects studies.

  1. Applicability of the Environmental Relative Moldiness Index for Quantification of Residential Mold Contamination in an Air Pollution Health Effects Study

    Directory of Open Access Journals (Sweden)

    Ali Kamal

    2014-01-01

    Full Text Available The Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS investigated the impact of exposure to traffic-related air pollution on the respiratory health of asthmatic children in Detroit, Michigan. Since indoor mold exposure may also contribute to asthma, floor dust samples were collected in participants homes (n=112 to assess mold contamination using the Environmental Relative Moldiness Index (ERMI. The repeatability of the ERMI over time, as well as ERMI differences between rooms and dust collection methods, was evaluated for insights into the application of the ERMI metric. ERMI values for the standard settled floor dust samples had a mean ± standard deviation of 14.5±7.9, indicating high levels of mold contamination. ERMI values for samples collected from the same home 1 to 7 months apart (n=52 were consistent and without systematic bias. ERMI values for separate bedroom and living room samples were highly correlated (r=0.69, n=66. Vacuum bag dust ERMI values were lower than for floor dust but correlated (r=0.58, n=28. These results support the use of the ERMI to evaluate residential mold exposure as a confounder in air pollution health effects studies.

  2. Applicability of the Environmental Relative Moldiness Index for Quantification of Residential Mold Contamination in an Air Pollution Health Effects Study

    Science.gov (United States)

    Kamal, Ali; Vesper, Stephen; Batterman, Stuart; Godwin, Christopher; Chavez-Camarena, Marina; Norris, Gary

    2014-01-01

    The Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS) investigated the impact of exposure to traffic-related air pollution on the respiratory health of asthmatic children in Detroit, Michigan. Since indoor mold exposure may also contribute to asthma, floor dust samples were collected in participants homes (n = 112) to assess mold contamination using the Environmental Relative Moldiness Index (ERMI). The repeatability of the ERMI over time, as well as ERMI differences between rooms and dust collection methods, was evaluated for insights into the application of the ERMI metric. ERMI values for the standard settled floor dust samples had a mean ± standard deviation of 14.5 ± 7.9, indicating high levels of mold contamination. ERMI values for samples collected from the same home 1 to 7 months apart (n = 52) were consistent and without systematic bias. ERMI values for separate bedroom and living room samples were highly correlated (r = 0.69, n = 66). Vacuum bag dust ERMI values were lower than for floor dust but correlated (r = 0.58, n = 28). These results support the use of the ERMI to evaluate residential mold exposure as a confounder in air pollution health effects studies. PMID:25431602

  3. {sup 21}Pb dating of sediments in a heavily contaminated drainage channel to the La Plata estuary in Buenos Aires, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Di Gregorio, D.E. [Departamento de Fisica, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, 1650 San Martin, Provincia de Buenos Aires (Argentina) and Escuela de Ciencia y Tecnologia, Universidad Nacional de Gral. San Martin, Martin de Irigoyen 3100, 1650 San Martin, Provincia de Buenos Aires (Argentina)]. E-mail: digregorio@tandar.cnea.gov.ar; Fernandez Niello, J.O. [Departamento de Fisica, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, 1650 San Martin, Provincia de Buenos Aires (Argentina); Escuela de Ciencia y Tecnologia, Universidad Nacional de Gral. San Martin, Martin de Irigoyen 3100, 1650 San Martin, Provincia de Buenos Aires (Argentina); Huck, H. [Departamento de Fisica, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, 1650 San Martin, Provincia de Buenos Aires (Argentina); Escuela de Ciencia y Tecnologia, Universidad Nacional de Gral. San Martin, Martin de Irigoyen 3100, 1650 San Martin, Provincia de Buenos Aires (Argentina); Somacal, H. [Escuela de Ciencia y Tecnologia, Universidad Nacional de Gral. San Martin, Martin de Irigoyen 3100, 1650 San Martin, Provincia de Buenos Aires (Argentina); Curutchet, G. [Escuela de Ciencia y Tecnologia, Universidad Nacional de Gral. San Martin, Martin de Irigoyen 3100, 1650 San Martin, Provincia de Buenos Aires (Argentina)

    2007-01-15

    Concentrations of {sup 21}Pb and {sup 137}Cs in sediment samples collected from two cores at a drainage channel to the La Plata river estuary in Buenos Aires, Argentina, were measured using ultralow-background detection systems. The {sup 21}Pb data were used to determine the rate of sediment accumulation of the sites. These results were correlated with some heavy metal (chromium and lead) concentrations of the samples in an attempt to characterize the historical input of contaminants due to the industrial development, which has taken place in this area over the last century. The {sup 137}Cs measurements demonstrate that cesium dating is not adequate in regions of the southern hemisphere.

  4. Micrometeorological Measurement of Fetch- and Atmospheric Stability-Dependent Air- Water Exchange of Legacy Semivolatile Organic Contaminants in Lake Superior

    Science.gov (United States)

    Perlinger, J. A.; Tobias, D. E.; Rowe, M. D.

    2008-12-01

    Coastal waters including the Laurentian Great Lakes are particularly susceptible to local, regional, and long- range transport and deposition of semivolatile organic contaminants (SOCs) as gases and/or associated with particles. Recently-marketed SOCs can be expected to undergo net deposition in surface waters, whereas legacy SOCs such as polychlorinated biphenyls (PCBs) are likely to be at equilibrium with respect to air-water exchange, or, if atmospheric concentrations decrease through, e.g., policy implementation, to undergo net gas emission. SOC air-water exchange flux is usually estimated using the two-film model. This model describes molecular diffusion through the air and water films adjacent to the air-water interface. Air-water exchange flux is estimated as the product of SOC fugacity, typically based on on-shore gaseous concentration measurements, and a transfer coefficient, the latter which is estimated from SOC properties and environmental conditions. The transfer coefficient formulation commonly applied neglects resistance to exchange in the internal boundary layer under atmospherically stable conditions, and the use of on-shore gaseous concentration neglects fetch-dependent equilibration, both of which will tend to cause overestimation of flux magnitude. Thus, for legacy chemicals or in any highly contaminated surface water, the rate at which the water is cleansed through gas emission tends to be over-predicted using this approach. Micrometeorological measurement of air-water exchange rates of legacy SOCs was carried out on ships during four transect experiments during off-shore flow in Lake Superior using novel multicapillary collection devices and thermal extraction technology to measure parts-per-quadrillion SOC levels. Employing sensible heat in the modified Bowen ratio, fluxes at three over-water stations along the transects were measured, along with up-wind, onshore gaseous concentration and aqueous concentration. The atmosphere was unstable for

  5. DEVELOPMENT OF MULTI-PHASE AND MULTI-COMPONENT FLOW MODEL WITH REACTION IN POROUS MEDIA FOR RISK ASSESSMENT ON SOIL CONTAMINATION DUE TO MINERAL OIL

    Science.gov (United States)

    Sakamoto, Yasuhide; Nishiwaki, Junko; Hara, Junko; Kawabe, Yoshishige; Sugai, Yuichi; Komai, Takeshi

    In late years, soil contamination due to mineral oil in vacant lots of oil factory and oil field has become obvious. Measure for soil contamina tion and risk assessment are neces sary for sustainable development of industrial activity. Especially, in addition to contaminated sites, various exposure paths for human body such as well water, soil and farm crop are supposed. So it is very important to comprehend the transport phenomena of contaminated material under the environments of soil and ground water. In this study, mineral oil as c ontaminated material consisting of mu lti-component such as aliphatic and aromatic series was modeled. Then numerical mode l for transport phenomena in surface soil and aquifer was constructed. On the basis of modeling for mineral oil, our numerical model consists of three-phase (oil, water and gas) forty three-component. This numerical model becomes base program for risk assessment system on soil contamination due to mineral oil. Using this numerical model, we carried out some numerical simulation for a laboratory-scale experiment on oil-water multi-phase flow. Relative permeability that dominate flow behavior in multi-phase condition was formulated and the validity of the numerical model developed in this study was considered.

  6. IMPACT OF ADDITIONALS CONTAMINANTS DUE TO ACID MINE DRAINAGE IN TRIBUTARIES OF THE PILCOMAYO RIVER FROM CERRO RICO, POTOSÍ, BOLIVIA

    Directory of Open Access Journals (Sweden)

    William H.J. Strosnider

    2014-09-01

    Full Text Available Intensive mining and processing of the polymetallic sulfide ore body of Cerro Rico de Potosí (Bolivia has occurred since 1545. To further investigate acid mine drainage (AMD discharges and their link to downstream contamination, data were gathered during two sampling events during the most extreme periods of the dry and wet seasons of one year. Concentrations of Ag, B, Ba, Mo, Sb, Se, Sn and V in AMD and receiving streams were greater than Bolivian discharge limits and receiving water body guidelines as well as international agricultural use standards. High concentrations of rare earth metals have been documented in this area. Results indicate that contamination from mining has a larger scope than previously thought and underscore the importance of remediation.

  7. Distribution pathways of hexachlorocyclohexane isomers in a soil-plant-air system. A case study with Cynara scolymus L. and Erica sp. plants grown in a contaminated site

    Energy Technology Data Exchange (ETDEWEB)

    Calvelo Pereira, R. [Departamento de Edafoloxia e Quimica Agricola, Facultade de Bioloxia, Universidade de Santiago de Compostela, Campus Sur, 15782 Santiago de Compostela (Spain)], E-mail: edrobert@usc.es; Monterroso, C.; Macias, F.; Camps-Arbestain, M. [Departamento de Edafoloxia e Quimica Agricola, Facultade de Bioloxia, Universidade de Santiago de Compostela, Campus Sur, 15782 Santiago de Compostela (Spain)

    2008-09-15

    This study focuses on the main routes of distribution and accumulation of different hexachlorocyclohexane (HCH) isomers (mainly {alpha}-, {beta}-, {gamma}- and {delta}-HCH) in a soil-plant-air system. A field assay was carried out with two plant species, Cynara scolymus L. and Erica sp., which were planted either: (i) directly in the HCH-contaminated soil; or (ii) in pots filled with uncontaminated soil, which were placed in the HCH-contaminated soil. Both plant species accumulated HCH in their tissues, with relatively higher accumulation in above-ground biomass than in roots. The {beta}-HCH isomer was the main isomer in all plant tissues. Adsorption of HCH by the roots from contaminated soil (soil {yields} root pathway) and adsorption through the aerial biomass from either the surrounding air, following volatilization of the contaminant (soil {yields} air {yields} shoot pathway), and/or contact with air-suspended particles contaminated with HCH (soil particles {yields} shoot pathway) were the main mechanisms of accumulation. These results may have important implications for the use of plants for reducing the transfer of contaminants via the atmosphere. - Hexachlorocyclohexane isomers are preferentially accumulated in above-ground tissues of plants grown in a heavily contaminated site.

  8. Aspidosperma subincanum I. characterisation, extraction of an uleine-enriched fraction and potential health hazard due to the contaminant ellipticine

    Directory of Open Access Journals (Sweden)

    Jean-Daniel Federlin

    2014-06-01

    Full Text Available The bark of the Brazilian tree Aspidosperma subincanum Mart. ex A. DC., Apocynaceae, has been characterised, and its constituents concentrated to obtain an uleine-enriched extract with the aim to produce food supplements. The concentration of the contaminant alkaloid ellipticine was assessed, and its potential to elicit toxic effects on consumers evaluated. It was found that this alkaloid posited no danger.

  9. Assessment of contamination of soil due to heavy metals around coal fired thermal power plants at Singrauli region of India.

    Science.gov (United States)

    Agrawal, Prashant; Mittal, Anugya; Prakash, Rajiv; Kumar, Manoj; Singh, T B; Tripathi, S K

    2010-08-01

    In the present study, an attempt was made to measure contamination of soil around four large coal-based Thermal Power Plants. The concentration of Cadmium, Lead, Arsenic and Nickel was estimated in all four directions from Thermal Power Plants. The soil in the study area was found to be contaminated to varying degrees from coal combustion byproducts. The soil drawn from various selected sites in each direction was largely contaminated by metals, predominantly higher within 2-4 km distance from Thermal Power Plant. Within 2-4 km, the mean maximum concentration of Cadmium, Lead, Arsenic and Nickel was 0.69, 13.69, 17.76, and 3.51 mg/kg, respectively. It was also observed that concentration was maximum in the prevalent wind direction. The concentration of Cadmium, Lead, Arsenic and Nickel was highest 0.69, 13.23, 17.29 and 3.56 mg/kg, respectively in west direction where wind was prevalent.

  10. Measurement of HO{sub x}{center_dot} production rate due to radon decay in air

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Huiling

    1993-08-01

    Radon in indoor air may cause the exposure of the public to excessive radioactivity. Radiolysis of water vapor in indoor air due to radon decay could produce ({center_dot}OH and HO{sub 2} {center_dot}) that may convert atmospheric constituents to compounds of lower vapor pressure. These lower vapor pressure compounds might then nucleate to form new particles in the indoor atmosphere. Chemical amplification was used to determine HO{sub x}{center_dot} production rate in indoor air caused by radon decay. Average HO{sub x}{center_dot} production rate was found to be (4.31{plus_minus}0.07) {times} 10{sup 5} HO{sub x}{center_dot} per Rn decay per second (Bq) 3.4 to 55.0% at 22C. This work provided G{sub (HO{sub x}{center_dot})}-value, 7.86{plus_minus}0.13 No./100 eV in air by directly measuring [HO{sub x}{center_dot}] formed from the radiolysis procedure. This G value implies that HO{sub x}{center_dot} produced by radon decay in air might be formed by multiple processes and may be result of positive ion-molecule reactions, primary radiolysis, and radical reactions. There is no obvious relation between HO{sub x}{center_dot} production rate and relative humidity. A laser-induced fluorescence (LIF) system has been used for {center_dot}OH production rate measurement; it consists of an excimer laser, a dye laser, a frequency doubler, a gaseous fluorescence chamber, and other optical and electronic parts. This system needs to be improved to eliminate the interferences of light scattering and artificial {center_dot}OH produced from the photolysis of O{sub 3}/H{sub 2}O.

  11. Changes in tropospheric composition and air quality due to stratospheric ozone depletion and climate change.

    Science.gov (United States)

    Wilson, S R; Solomon, K R; Tang, X

    2007-03-01

    It is well-understood that reductions in air quality play a significant role in both environmental and human health. Interactions between ozone depletion and global climate change will significantly alter atmospheric chemistry which, in turn, will cause changes in concentrations of natural and human-made gases and aerosols. Models predict that tropospheric ozone near the surface will increase globally by up to 10 to 30 ppbv (33 to 100% increase) during the period 2000 to 2100. With the increase in the amount of the stratospheric ozone, increased transport from the stratosphere to the troposphere will result in different responses in polluted and unpolluted areas. In contrast, global changes in tropospheric hydroxyl radical (OH) are not predicted to be large, except where influenced by the presence of oxidizable organic matter, such as from large-scale forest fires. Recent measurements in a relatively clean location over 5 years showed that OH concentrations can be predicted by the intensity of solar ultraviolet radiation. If this relationship is confirmed by further observations, this approach could be used to simplify assessments of air quality. Analysis of surface-level ozone observations in Antarctica suggests that there has been a significant change in the chemistry of the boundary layer of the atmosphere in this region as a result of stratospheric ozone depletion. The oxidation potential of the Antarctic boundary layer is estimated to be greater now than before the development of the ozone hole. Recent modeling studies have suggested that iodine and iodine-containing substances from natural sources, such as the ocean, may increase stratospheric ozone depletion significantly in polar regions during spring. Given the uncertainty of the fate of iodine in the stratosphere, the results may also be relevant for stratospheric ozone depletion and measurements of the influence of these substances on ozone depletion should be considered in the future. In agreement with

  12. Contamination monitoring activities in Kanupp

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, S.S. [Karachi Nuclear Power Plant (Pakistan)

    1997-06-01

    The Karachi Nuclear Power Plant (Kanupp) is a 137 MWe pressurized heavy water reactor, designed and erected by the Canadian General Electric Company as a turn key project. The plant is in operation since it was commissioned in the year 1972. It is located at the Arabian Sea Coast about 15 miles to the west of Karachi. During its more than two decades of operation, the plant has generated about 8 billion units of electricity with an average life time availability factor of 60%. In Kanupp, radioactive contamination may exit due to the release of fission product, activation products etc., which may somehow escape from its confinement and may contaminate surface or other media such as air, water etc. In this paper, following items are described: main aspects of contamination, status of contamination monitoring, need of contamination monitoring, radiation protection activity, instruments, contamination, current status of contamination survey materials and their disposal, and environmental monitoring. (G.K.)

  13. Enhanced formation of secondary air pollutants and aggravation of urban smog due to crop residue burning emissions in North India

    Science.gov (United States)

    Sarkar, Chinmoy; Kumar, Vinod; Sinha, Vinayak

    2013-04-01

    Biomass burning causes intense perturbations to regional atmospheric chemistry and air quality and is a significant global source of reactive pollutants to the atmosphere (Andreae and Merlet, 2001). In November 2012, large areas in North India including New Delhi experienced several weeks of aggravated smog and poor air quality due to the impact of crop residue burning, which is a biannual post harvest activity that occurs during Oct-Nov and April-May every year in the agricultural belts of North western India. In-situ high temporal resolution (1 measurement every minute) measurements of a suite of volatile organic compounds measured using proton transfer reaction mass spectrometry (PTR-MS) such as acetonitrile (biomass burning tracer) and aromatic hydrocarbons were performed simultaneously with carbon monoxide, nitrogen oxides, ozone and aerosol mass concentrations (PM 2.5 and PM 10) at a suburban site (30.667°N, 76.729°E and 310 m asl), impacted by air masses that had passed over the burning fields less than 72 hours ago. By using data from the same season but before the post harvest crop residue burning activity had commenced, we were able to quantify enhancements in ambient levels of the measured species due to the crop residue burning activity. When air masses influenced by the fire emissions reached the measurement site, peak values of about 8 ppbV acetonitrile, 4 ppmV CO, 100 ppbV NOx , 30 ppbV toluene and 15 ppbV benzene were observed which represented a factor of 2-5 increase over their ambient levels in the non-fire influenced period. Emission ratios of aromatic hydrocarbons/CO also showed a marked increase. Non fire event (N.F. E.) influenced and fire event (F.E.) influenced air masses had the following emission ratio enhancements: benzene/CO (N.F.E = 3; F.E. = 5), toluene/CO (N.F.E = 4; F.E. = 8.7) and sum of C8 aromatics/CO (N.F.E = 4; F.E. = 7.3) and sum of C9 aromatics/CO (N.F.E = 2.6; F.E. = 3.4). The OH reactivity of air masses which has strong

  14. Perfluorinated acids in air, rain, snow, surface runoff, and lakes: relative importance of pathways to contamination of urban lakes.

    Science.gov (United States)

    Kim, Seung-Kyu; Kannan, Kurunthachalam

    2007-12-15

    Concentrations of perfluorinated acids (PFAs) were measured in various environmental matrices (air, rain, snow, surface runoff water, and lake water) in an urban area, to enable identification of sources and pathways of PFAs to urban water bodies. Total PFA concentrations ranged from 8.28 to 16.0 pg/ m3 (mean 11.3) in bulk air (sum of vapor and particulate phases), 0.91 to 13.2 ng/L (6.19) in rainwater, 0.91 to 23.9 ng/L (7.98) in snow, 1.11-81.8 ng/L (15.1 ng/L) in surface runoff water (SRW), and 9.49 to 35.9 ng/L (21.8) in lake water. Perfluorooctanoic acid (PFOA) was the predominant compound, accounting for > 35% of the total PFA concentrations, in all environmental matrices analyzed. Concentrations and relative compositions of PFAs in SRW were similar to those found for urban lakes. SRW contributes to contamination by PFOA in urban lakes. The measured concentration ratios of FTOH to PFOA in air were 1-2 orders of magnitude lower than the ratios calculated based on an assumption of exclusive atmospheric oxidation of FTOHs. Nevertheless, the mass balance analysis suggested the presence of an unknown input pathway that could contribute to a significant amount of total PFOA loadings to the lake. Flux estimates of PFOA at the air-water interface in the urban lake suggest net volatilization from water.

  15. DFT Study On Effects of CO2 Contamination in Non-Aqueous Li-Air Batteries

    DEFF Research Database (Denmark)

    Mekonnen, Yedilfana Setarge; Mýrdal, Jón Steinar Garðarsson; Vegge, Tejs

    2013-01-01

    Density Functional Theory (DFT) studies on the effects of carbon dioxide (CO2) contamination at the cathode of rechargeable non-aqueous Li-O2 batteries, where the insulating material Lithium peroxide (Li2O2) is the main discharge product. The Li2O2 growth mechanism and overpotentials are investig......Density Functional Theory (DFT) studies on the effects of carbon dioxide (CO2) contamination at the cathode of rechargeable non-aqueous Li-O2 batteries, where the insulating material Lithium peroxide (Li2O2) is the main discharge product. The Li2O2 growth mechanism and overpotentials...

  16. Potential Environment and Public Health Risk Due to Contamination of Heavy Metals from Industrial Waste Water in Lam Thao, Phu Tho, Vietnam

    Directory of Open Access Journals (Sweden)

    Nguyen C. Vinh

    2012-01-01

    Full Text Available Problem statement: In Vietnam, rice cultivation plays an important role in national economic development and food security. However, rice production is facing many problems associated with rapid industrialization and urbanization in the country. Resultant emissions of solid and liquid wastes are often untreated and discharged directly to agricultural land. These practices have potential impacts on the environment and human health. Approach: The research was carried out within the frame of the collaborative research project “Towards the mitigation of environment and public health risks due to heavy metal contamination in irrigated rice-based systems of Vietnam” in 2006-2010. The study was implemented in the Lam Thao district, Phu Tho province with the aim to assess the effects of wastewater and other contamination sources on the environment and public health. Results: Surface water and soil in the field showed signs of significant contamination by wastewater from the industrial zones. Bio-indicators (DO, COD, BOD5 in the surface water were also strongly affected by waste. Paddy fields around the industrial zones had an elevated risk of heavy metal contamination (Cu, Zn, As, Cd and Pb, with concentrations exceeding Vietnamese Maximum Acceptable Concentrations (MACs for Cu, Zn, Cd and Pb. Soil contamination with heavy metals was resulting in elevated concentrations in rice grain. Where consumption of locally-produced food was high, exposure of individuals to heavy metals could present a public health risk. The partial Hazard Quotient (HQ; a ratio derived from comparing estimated exposure to heavy metals, i.e., Cd, (with toxicologically-derived„ safe’ daily doses for rice and vegetables (water spinach and the integrated Hazard Quotient of rice and vegetables (HQi was consistently greater in areas with soil contamination than in the reference area using Red River water for irrigation. The HQi for Cd was particularly high for children below the

  17. Engineering and environmental remediation scenarios due to leakage from the Gulf War oil spill using 3-D numerical contaminant modellings

    Science.gov (United States)

    Yihdego, Yohannes; Al-Weshah, Radwan A.

    2016-12-01

    The transport groundwater modelling has been undertaken to assess potential remediation scenarios and provide an optimal remediation options for consideration. The purpose of the study was to allow 50 years of predictive remediation simulation time. The results depict the likely total petroleum hydrocarbon migration pattern in the area under the worst-case scenario. The remediation scenario simulations indicate that do nothing approach will likely not achieve the target water quality within 50 years. Similarly, complete source removal approach will also likely not achieve the target water quality within 50 years. Partial source removal could be expected to remove a significant portion of the contaminant mass, but would increase the rate of contaminant recharge in the short to medium term. The pump-treat-reinject simulation indicates that the option appears feasible and could achieve a reduction in the area of the 0.01 mg/L TPH contour area for both Raudhatain and Umm Al-Aish by 35 and 30%, respectively, within 50 years. The rate of improvement and the completion date would depend on a range of factors such as bore field arrangements, pumping rates, reinjection water quality and additional volumes being introduced and require further optimisation and field pilot trials.

  18. Variation of annual effective dose due to radon level in indoor air in Marwar region of Rajasthan, India

    Energy Technology Data Exchange (ETDEWEB)

    Rani, Asha, E-mail: ashasachdeva78@gmail.com [Department of Applied Science, Ferozepur College of Engineering and Technology, Farozshah, Ferozepur-142052, Punjab (India); Mittal, Sudhir, E-mail: sudhirmittal03@gmail.com [Department of Applied Sciences, Punjab Technical University, Jalandhar-144601, Punjab (India); Mehra, Rohit [Department of Physics, Dr. B.R.Ambedkar National Institute of Technology, Jalandhar-144011 (India)

    2015-08-28

    In the present work, indoor radon and thoron measurements have been carried out from different locations of Jodhpur and Nagaur districts of Northern Rajasthan, India using RAD7, a solid state alpha detector. The radon and thoron concentration in indoor air varies from 8.75 to 61.25 Bq m{sup −3} and 32.7 to 147.2 Bq m{sup −3} with the mean value of 32 and 73 Bq m{sup −3} respectively. The observed indoor radon concentration values are well below the action level recommended by International Commission on Radiological Protection (200-300 Bq m{sup −3}) and Environmental Protection Agency (148 Bq m{sup −3}). The survey reveals that the thoron concentration values in the indoor air are well within the International Commission on Radiological Protection (2005). The calculated total annual effective dose due to radon level in indoor air varies from 0.22 to 1.54 mSv y{sup −1} with the mean value of 0.81 mSv y{sup −1} which is less than even the lower limit of action level 3-10 mSv y{sup −1} recommended by International Commission on Radiological Protection (2005)

  19. Assessment of internal contamination problems associated with bioregenerative air/water purification systems

    Science.gov (United States)

    Johnson, Anne H.; Bounds, B. Keith; Gardner, Warren

    1990-01-01

    The emphasis is to characterize the mechanisms of bioregenerative revitalization of air and water as well as to assess the possible risks associated with such a system in a closed environment. Marsh and aquatic plants are utilized for purposes of wastewater treatment as well as possible desalinization and demineralization. Foliage plants are also being screened for their ability to remove toxic organics from ambient air. Preliminary test results indicate that treated wastewater is typically of potable quality with numbers of pathogens such as Salmonella and Shigella significantly reduced by the artificial marsh system. Microbiological analyses of ambient air indicate the presence of bacilli as well as thermophilic actinomycetes.

  20. Distribution pathways of hexachlorocyclohexane isomers in a soil-plant-air system. A case study with Cynara scolymus L. and Erica sp. plants grown in a contaminated site.

    Science.gov (United States)

    Pereira, R Calvelo; Monterroso, C; Macías, F; Camps-Arbestain, M

    2008-09-01

    This study focuses on the main routes of distribution and accumulation of different hexachlorocyclohexane (HCH) isomers (mainly alpha-, beta-, gamma- and delta-HCH) in a soil-plant-air system. A field assay was carried out with two plant species, Cynara scolymus L. and Erica sp., which were planted either: (i) directly in the HCH-contaminated soil; or (ii) in pots filled with uncontaminated soil, which were placed in the HCH-contaminated soil. Both plant species accumulated HCH in their tissues, with relatively higher accumulation in above-ground biomass than in roots. The beta-HCH isomer was the main isomer in all plant tissues. Adsorption of HCH by the roots from contaminated soil (soil-->root pathway) and adsorption through the aerial biomass from either the surrounding air, following volatilization of the contaminant (soil-->air-->shoot pathway), and/or contact with air-suspended particles contaminated with HCH (soil particles-->shoot pathway) were the main mechanisms of accumulation. These results may have important implications for the use of plants for reducing the transfer of contaminants via the atmosphere.

  1. Monitoring of environmental contaminants in air and precipitation, annual report 2014

    OpenAIRE

    Nizzetto, Pernilla Bohlin; Aas, Wenche; Warner, Nicholas Alexander

    2015-01-01

    This report presents results from 2014 for persistent organic pollutants (POPs) and heavy metals from the rural air- and precipitation chemistry monitoring network in Norway. These results are compared to previous years.

  2. Environmental contaminants in fish from Mere Brook - U.S. Naval Air Station, Brunswick, Maine

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Mere Brook bisects three former landfills at the U.S. Naval Air Station in Brunswick, Maine (NASB). Leachate, soil, and sediment analyzed during Superfund remedial...

  3. Application of a prospective model for calculating worker exposure due to the air pathway for operations in a laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Grimbergen, T.W.M. [Department of Occupational Health, Safety and Environment, Vrije Universiteit, Amsterdam (Netherlands); NRG Radiation and Environment, PO Box 9034, 6800 ES Arnhem (Netherlands); Wiegman, M.M. [VU Medisch Centrum, Department of Nuclear Medicine and PET-Research, Amsterdam (Netherlands)

    2007-07-01

    In order to arrive at recommendations for guidelines on maximum allowable quantities of radioactive material in laboratories, a proposed mathematical model was used for the calculation of transfer fractions for the air pathway. A set of incident scenarios was defined, including spilling, leakage and failure of the fume hood. For these 'common incidents', dose constraints of 1 mSv and 0.1 mSv are proposed in case the operations are being performed in a controlled area and supervised area, respectively. In addition, a dose constraint of 1 {mu}Sv is proposed for each operation under regular working conditions. Combining these dose constraints and the transfer fractions calculated with the proposed model, maximum allowable quantities were calculated for different laboratory operations and situations. Provided that the calculated transfer fractions can be experimentally validated and the dose constraints are acceptable, it can be concluded from the results that the dose constraint for incidents is the most restrictive one. For non-volatile materials this approach leads to quantities much larger than commonly accepted. In those cases, the results of the calculations in this study suggest that limitation of the quantity of radioactive material, which can be handled safely, should be based on other considerations than the inhalation risks. Examples of such considerations might be the level of external exposure, uncontrolled spread of radioactive material by surface contamination, emissions in the environment and severe accidents like fire. (authors)

  4. Application of a prospective model for calculating worker exposure due to the air pathway for operations in a laboratory.

    Science.gov (United States)

    Grimbergen, T W M; Wiegman, M M

    2007-01-01

    In order to arrive at recommendations for guidelines on maximum allowable quantities of radioactive material in laboratories, a proposed mathematical model was used for the calculation of transfer fractions for the air pathway. A set of incident scenarios was defined, including spilling, leakage and failure of the fume hood. For these 'common incidents', dose constraints of 1 mSv and 0.1 mSv are proposed in case the operations are being performed in a controlled area and supervised area, respectively. In addition, a dose constraint of 1 microSv is proposed for each operation under regular working conditions. Combining these dose constraints and the transfer fractions calculated with the proposed model, maximum allowable quantities were calculated for different laboratory operations and situations. Provided that the calculated transfer fractions can be experimentally validated and the dose constraints are acceptable, it can be concluded from the results that the dose constraint for incidents is the most restrictive one. For non-volatile materials this approach leads to quantities much larger than commonly accepted. In those cases, the results of the calculations in this study suggest that limitation of the quantity of radioactive material, which can be handled safely, should be based on other considerations than the inhalation risks. Examples of such considerations might be the level of external exposure, uncontrolled spread of radioactive material by surface contamination, emissions in the environment and severe accidents like fire.

  5. Metabolic Effects in the Bivalve Perna perna and Mytilus galloprovincialis: Impact on the Environment due to Contamination by Copper

    Directory of Open Access Journals (Sweden)

    Mohamed Brahim Errahmani

    2014-01-01

    Full Text Available This work presents the study of the effects of acute exposure to various concentrations of copper from 0.03 to 0.59 μmol·L−1 on the metabolic activities (nitrogen and phosphorus, protein levels, catalase (CAT enzyme activities, and the biological response malondialdehyde (MDA in the mollusks Perna perna and Mytilus galloprovincialis. The concentrations above 0.88 μmol·L−1 have proven to be lethal to P. perna. The results show slight disturbances of metabolism as a result of pollutant and a significant correlation between metal contamination and ammonia nitrogen levels, resulting in an increase in the latter after 48 h of M. galloprovincialis exposure to 0.59 μmol·L−1 of copper concentrations. CAT was rapidly induced even by low concentrations of copper; MDA was increased only with low concentrations of copper in P. perna.

  6. Extent and bioavailability of trace metal contamination due to acid rock drainage in Pennask Creek, British Columbia, Canada

    Science.gov (United States)

    Walls, L. D.; Li, L. Y.; Hall, K. J.

    2010-05-01

    Pennask Creek is one of the most important rainbow trout producing streams in British Columbia (BC). Much of the Pennask Creek watershed is located within a BC Parks Protected Area, which was set aside to protect the spawning and rearing habitat of this wild rainbow trout population. Construction of Highway 97C, which bisects the Pennask Creek watershed, resulted in the exposure of a highly pyritic rock formation, which began releasing acid rock drainage and causing metals to be leached into Highway Creek, a tributary of Pennask Creek. Previous studies commissioned by the BC Ministry of Transportation and Infrastructure indicate that Highway Creek yields fewer invertebrates and elevated levels of some metals in the water when compared with downstream sites in Pennask Creek. This study examines the impacts of this acid rock drainage and metal leaching by determining the extent of trace metal contamination in the water and sediments of the Pennask Creek watershed and determining the bioavailability of these trace metals. Preliminary results indicate concentrations of Al, Cu, and Zn in the water as well as levels of total As, Cu, Fe, Ni, and Zn in the sediments that are above the BC Water and Sediment Quality Guidelines for the Protection of Aquatic Life. The highest level of trace metal contamination is found in Highway Creek, downstream of Highway 97C, with concentrations generally returning to near background levels downstream of the confluence with Pennask Creek. Levels of Cu in the water and Zn in the sediments appear to be of greatest concern in areas furthest from the highway.

  7. The Impact of Individual Anthropogenic Emissions Sectors on the Global Burden of Human Mortality due to Ambient Air Pollution

    Science.gov (United States)

    Silva, Raquel A.; Adelman, Zachariah; Fry, Meridith M.; West, J. Jason

    2016-01-01

    Background: Exposure to ozone and fine particulate matter (PM2.5) can cause adverse health effects, including premature mortality due to cardiopulmonary diseases and lung cancer. Recent studies quantify global air pollution mortality but not the contribution of different emissions sectors, or they focus on a specific sector. Objectives: We estimated the global mortality burden of anthropogenic ozone and PM2.5, and the impact of five emissions sectors, using a global chemical transport model at a finer horizontal resolution (0.67° × 0.5°) than previous studies. Methods: We performed simulations for 2005 using the Model for Ozone and Related Chemical Tracers, version 4 (MOZART-4), zeroing out all anthropogenic emissions and emissions from specific sectors (All Transportation, Land Transportation, Energy, Industry, and Residential and Commercial). We estimated premature mortality using a log-linear concentration–response function for ozone and an integrated exposure–response model for PM2.5. Results: We estimated 2.23 (95% CI: 1.04, 3.33) million deaths/year related to anthropogenic PM2.5, with the highest mortality in East Asia (48%). The Residential and Commercial sector had the greatest impact globally—675 (95% CI: 428, 899) thousand deaths/year—and in most regions. Land Transportation dominated in North America (32% of total anthropogenic PM2.5 mortality), and it had nearly the same impact (24%) as Residential and Commercial (27%) in Europe. Anthropogenic ozone was associated with 493 (95% CI: 122, 989) thousand deaths/year, with the Land Transportation sector having the greatest impact globally (16%). Conclusions: The contributions of emissions sectors to ambient air pollution–related mortality differ among regions, suggesting region-specific air pollution control strategies. Global sector-specific actions targeting Land Transportation (ozone) and Residential and Commercial (PM2.5) sectors would particularly benefit human health. Citation: Silva RA

  8. Nonlinear Least-Squares Based Method for Identifying and Quantifying Single and Mixed Contaminants in Air with an Electronic Nose

    Directory of Open Access Journals (Sweden)

    Margaret A. Ryan

    2005-12-01

    Full Text Available The Jet Propulsion Laboratory has recently developed and built an electronic nose(ENose using a polymer-carbon composite sensing array. This ENose is designed to be usedfor air quality monitoring in an enclosed space, and is designed to detect, identify andquantify common contaminants at concentrations in the parts-per-million range. Itscapabilities were demonstrated in an experiment aboard the National Aeronautics and SpaceAdministration’s Space Shuttle Flight STS-95. This paper describes a modified nonlinearleast-squares based algorithm developed to analyze data taken by the ENose, and itsperformance for the identification and quantification of single gases and binary mixtures oftwelve target analytes in clean air. Results from laboratory-controlled events demonstrate theeffectiveness of the algorithm to identify and quantify a gas event if concentration exceedsthe ENose detection threshold. Results from the flight test demonstrate that the algorithmcorrectly identifies and quantifies all registered events (planned or unplanned, as singles ormixtures with no false positives and no inconsistencies with the logged events and theindependent analysis of air samples.

  9. Enhancement of the microbial community biomass and diversity during air sparging bioremediation of a soil highly contaminated with kerosene and BTEX.

    Science.gov (United States)

    Kabelitz, Nadja; Machackova, Jirina; Imfeld, Gwenaël; Brennerova, Maria; Pieper, Dietmar H; Heipieper, Hermann J; Junca, Howard

    2009-03-01

    In order to obtain insights in complexity shifts taking place in natural microbial communities under strong selective pressure, soils from a former air force base in the Czech Republic, highly contaminated with jet fuel and at different stages of a bioremediation air sparging treatment, were analyzed. By tracking phospholipid fatty acids and 16S rRNA genes, a detailed monitoring of the changes in quantities and composition of the microbial communities developed at different stages of the bioventing treatment progress was performed. Depending on the length of the air sparging treatment that led to a significant reduction in the contamination level, we observed a clear shift in the soil microbial community being dominated by Pseudomonads under the harsh conditions of high aromatic contamination to a status of low aromatic concentrations, increased biomass content, and a complex composition with diverse bacterial taxonomical branches.

  10. Enhancement of the microbial community biomass and diversity during air sparging bioremediation of a soil highly contaminated with kerosene and BTEX

    Energy Technology Data Exchange (ETDEWEB)

    Kabelitz, Nadja; Heipieper, Hermann J. [Helmholtz Centre for Environmental Research (UFZ), Leipzig (Germany). Dept. of Bioremediation; Machackova, Jirina [Earth Tech CZ s.r.o., Prague (Czech Republic); Imfeld, Gwenael [Helmholtz Centre for Environmental Research (UFZ), Leipzig (Germany). Dept. of Isotope Biogeochemistry; Brennerova, Maria [Czech Academy of Sciences, Prague (CZ). Inst. of Microbiology (IMIC); Pieper, Dietmar H.; Junca, Howard [Helmholtz Centre for Infection Research (HZI), Braunschweig (Germany). Biodegradation Research Group

    2009-03-15

    In order to obtain insights in complexity shifts taking place in natural microbial communities under strong selective pressure, soils from a former air force base in the Czech Republic, highly contaminated with jet fuel and at different stages of a bioremediation air sparging treatment, were analyzed. By tracking phospholipid fatty acids and 16S rRNA genes, a detailed monitoring of the changes in quantities and composition of the microbial communities developed at different stages of the bioventing treatment progress was performed. Depending on the length of the air sparging treatment that led to a significant reduction in the contamination level, we observed a clear shift in the soil microbial community being dominated by Pseudomonads under the harsh conditions of high aromatic contamination to a status of low aromatic concentrations, increased biomass content, and a complex composition with diverse bacterial taxonomical branches. (orig.)

  11. Study on Decomposition of Indoor Air Contaminants by Pulsed Atmospheric Microplasma

    OpenAIRE

    Tomoya Kuwabara; Marius Blajan; Kazuo Shimizu

    2012-01-01

    Decomposition of formaldehyde (HCHO) by a microplasma reactor in order to improve Indoor Air Quality (IAQ) was achieved. HCHO was removed from air using one pass through reactor treatment (5 L/min). From an initial concentration of HCHO of 0.7 ppm about 96% was removed in one pass treatment using a discharge power of 0.3 W provided by a high voltage amplifier and a Marx Generator with MOSFET switches as pulsed power supplies. Moreover microplasma driven by the Marx Generator did not generate ...

  12. Mineralogical and geomicrobial examination of soil contamination by radioactive Cs due to 2011 Fukushima Daiichi Nuclear Power Plant accident

    Science.gov (United States)

    Akai, Junji; Nomura, Nao; Matsushita, Shin; Kudo, Hisaaki; Fukuhara, Haruo; Matsuoka, Shiro; Matsumoto, Jinko

    Soil contamination by radioactive Cs from Fukushima Daiichi Nuclear Power Plant accident was investigated. Absorption and desorption experiments of Cs were conducted for several phyllosillicates (kaolinite, sericite, montmorillonite, vermiculite, chrysotile and biotite), zeolite and solid organic matter (dead and green leaves). The results confirmed the characteristic sorption and desorption of Cs by these materials. The 2:1 type phyllosilicate, especially, vermiculite and montmorillonite absorbed Cs well. Heated vermiculite for agricultural use and weathered montmorillonite also adsorbed Cs. Leaves also absorbed Cs considerably but easily desorbed it. In summary, the relative capacity and strength of different materials for sorption of Cs followed the order: zeolite (clinoptilolite) > 2:1 type clay mineral > 1:1 type clay mineral > dead and green leaves. Culture experiments using bacteria of both naturally living on dead leaves in Iitate village, Fukushima Pref. and bacterial strains of Bacillus subtillis, Rhodococus erythropolis, Streptomyces aomiensis and Actinomycetospora chlora were carried out. Non-radioactive 1% Cs solution (CsCl) was added to the culture media. Two types of strong or considerable bacterial uptakes of Cs were found in bacterial cells. One is that Cs was contained mainly as globules inside bacteria and the other is that Cs was absorbed in the whole bacterial cells. The globules consisted mainly of Cs and P. Based on all these results, future diffusion and re-circulation behavior of Cs in the surface environment was discussed.

  13. Microbial Contamination on Used Surgical Masks among Hospital Personnel and Microbial Air Quality in their Working Wards: A Hospital in Bangkok

    Directory of Open Access Journals (Sweden)

    Pipat Luksamijarulkul

    2014-09-01

    Full Text Available Objective: To assess the relationship of bacterial and fungal contamination on used surgical masks worn by the hospital personnel and microbial air quality in their working wards. Methods: This is a cross-sectional study of 230 used surgical masks collected from 214 hospital personnel, and 215 indoor air samples collected from their working wards to culture for bacterial and fungal counts. This study was carried out at the hospital in Bangkok. Group or genus of isolated bacteria and fungi were preliminarily identified by Gram’s stain and lacto-phenol cotton blue. Data were analyzed using paired t-test and Pearson’s correlation coefficient at the significant level of p<0.050. Results: Means and standard deviation of bacterial and fungal contamination on inside area of the used masks were 47 ± 56 and 15 ± 9 cfu/ml/piece, and on outside area were 166 ± 199 and 34 ± 18 cfu/ml/piece, respectively, p<0.001. The bacterial and fungal contamination on used masks from hospital personnel working in the male and female medical wards and out-patient department, as well as the bacterial and fungal counts of the indoor air sample collected from the same area were relatively higher than the other wards. The predominant isolated bacteria and fungi contaminated on inside and outside areas of the used masks and air samples were similar (Staphylococcus spp. and Aspergillus spp.; respectively. For its relationship, results found that bacterial and fungal counts in air samples showed significantly positive correlation with the bacterial contamination load on outside area of the used masks, r=0.16, p=0.018 and r=0.21, p=0.003, respectively. Conclusion: High bacterial contamination on outside area of the used masks was demonstrated, and it showed a significant correlation with microbial air quality of working wards.

  14. A RAPID DNA EXTRACTION METHOD FOR PCR IDENTIFICATION OF FUNGAL INDOOR AIR CONTAMINANTS

    Science.gov (United States)

    Following air sampling, fungal DNA needs to be extracted and purified to a state suitable for laboratory use. Our laboratory has developed a simple method of extraction and purification of fungal DNA appropriate for enzymatic manipulation and polymerase chain reaction (PCR) appli...

  15. Secondary pollutants or macro ecological contamination: A biotic contamination of the air. Contaminantes secundarios o contaminacion macroecologica: contaminacion abiotica de la atmosfera

    Energy Technology Data Exchange (ETDEWEB)

    Moreno Abil, O. (Catedra de Medicina Preventiva y Salud Publica Facultad de Medicina, Universidad de Granada (Spain))

    1994-01-01

    The primary and secondary contaminants are analyzed by the author. As well the effects of these contaminants by man and the ecosystem. The main topics are: (1) Photochemistry contamination (photo chemical smog) (2) Acid rain and its effects. (3) Depletion of ozone layer.

  16. Particle re-entrainment from a powder deposit in an horizontal air flow; Mise en suspension d'une contamination particulaire par ecoulement d'air

    Energy Technology Data Exchange (ETDEWEB)

    Alloul, L.; Witschger, O. [CEA/Saclay, Inst. de Protection et de Surete Nucleaire, IPSN/DPEA/SERAC, Lab. de Physique et Metrologie des Aerosols et du Confinement, 91 - Gif-sur-Yvette (France); Renoux, A. [Paris-12 Univ., Lab. de Physique des Aerosols et de Transfert des Contaminations, 94 - Creteil (France); Le Dur, D. [Aerolab, 91 - Courtaboeuf (France); Monnatte, J. [COGEMA, Branche Combustible et Recyclage, Service Qualite Surete, 78 - Saint-Quentin-en-Yvelines (France)

    2000-07-01

    Particle re-entrainment from surfaces to turbulent air flow is an important subject in many different fields like nuclear safety, environmental air pollution, sediment transport by wind, surface contamination in semiconductor operations. Theoretical and experimental studies have been numerous and cover different aspects of the phenomena. Although a number of theoretical works have been devoted for describing the mechanisms of detachment of primary spherical particles form flat smooth surfaces in a turbulent flow, experimental data are still needed in order to comparison. Moreover, the knowledge of the effect of parameters related to the deposit (monolayer, multilayer, cone-like pile), the powder particles (particle-size distribution, adhesive properties), the surface (roughness,...),the airflow (velocity, acceleration, turbulence) or the environment (humidity,...) is still in an elementary stage. The main objective of our work is to contribute to the understanding and quantification of the parameters that govern the particle re-entrainment from a powder deposit in an turbulent horizontal airflow. Therefore, a new experimental facility called BISE (french acronym for wind tunnel for studying particle re-entrainment by airflow) has been designed and built in our laboratory. (authors)

  17. ASSESSMENT OF THE AVERAGE ANNUAL EFFECTIVE DOSES FOR THE INHABITANTS OF THE SETTLEMENTS LOCATED IN THE TERRITORIES CONTAMINATED DUE TO THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    N. G. Vlasova

    2012-01-01

    Full Text Available Catalogue of the average annual effective exposure doses of the inhabitants of the territories contaminated due to the Chernobul accident had been developed according to the method of the assessment of the average annual effective exposure doses of the settlements inhabitants. The cost-efficacy of the use of the average annual effective dose assessment method was 250 000 USD for the current 5 years. Average annual effective dose exceeded 1 mSv/year for 191 Belarus settlements from 2613. About 50 000 persons are living in these settlements.

  18. Modeling of the fate of radionuclides in urban sewer systems after contamination due to nuclear or radiological incidents

    DEFF Research Database (Denmark)

    Urso, L.; Kaiser, J.C.; Andersson, Kasper Grann

    2013-01-01

    and is collected in a sewage plant. Up to now the potential exposure caused by this process has received little attention and is estimated here with simulation models. The commercial rainfall-runoff model for urban sewer systems KANALþþ has been extended to include transport of radionuclides from surfaces through...... Device (RDD) with Cs-137 is detonated in a small inhabited area whose drainage system is realistically modeled. The transition of deposited radionuclides due to rainfall into the surface runoff is accounted for by different nuclide-specific entrainment coefficients for paved and unpaved surfaces...

  19. Air mercury contamination in the gold mining town of Portovelo, Ecuador.

    Science.gov (United States)

    González-Carrasco, Víctor; Velasquez-Lopez, Patricio C; Olivero-Verbel, Jesús; Pájaro-Castro, Nerlis

    2011-09-01

    Portovelo is one of the oldest gold mining towns in Ecuador. Artisanal gold mining still uses mercury in the process of gold recovery. In this study, mercury concentrations in the air of Portovelo were evaluated. High mercury levels in the ambient were found in El Pache sector, where most gold mining processing plants are located. These varied between 2,356.7 ± 1,807.6 and 3,699.5 ± 1,225.3 ng/m(3) during the rainy and dry seasons, respectively. Lower levels were detected in the urban (central) area of Portovelo, with 214.6 ± 43.7 ng/m(3) in the rainy season and 574.2 ± 72.8 ng/m(3) in the dry season, exceeding the Agency for Toxic Substances and Disease Registry minimum risk level of 200 ng/m(3). Average mercury concentrations in exhaled air from miners, measured before and after amalgam burning ranged between 179-1,352 and 2,007-3,389 ng/m(3), respectively. These data suggest Portovelo air is polluted with mercury and humans are being dangerously exposed. Therefore, strong actions must be undertaken to protect human and environmental health, including changing gold recovery systems.

  20. Organophosphates in aircraft cabin and cockpit air--method development and measurements of contaminants.

    Science.gov (United States)

    Solbu, Kasper; Daae, Hanne Line; Olsen, Raymond; Thorud, Syvert; Ellingsen, Dag Gunnar; Lindgren, Torsten; Bakke, Berit; Lundanes, Elsa; Molander, Paal

    2011-05-01

    Methods for measurements and the potential for occupational exposure to organophosphates (OPs) originating from turbine and hydraulic oils among flying personnel in the aviation industry are described. Different sampling methods were applied, including active within-day methods for OPs and VOCs, newly developed passive long-term sample methods (deposition of OPs to wipe surface areas and to activated charcoal cloths), and measurements of OPs in high-efficiency particulate air (HEPA) recirculation filters (n = 6). In total, 95 and 72 within-day OP and VOC samples, respectively, have been collected during 47 flights in six different models of turbine jet engine, propeller and helicopter aircrafts (n = 40). In general, the OP air levels from the within-day samples were low. The most relevant OP in this regard originating from turbine and engine oils, tricresyl phosphate (TCP), was detected in only 4% of the samples (min-max cockpit air, was an order of magnitude higher as compared to after engine replacement (p = 0.02).

  1. An assessment of the Photon Contamination due to Bremsstrahlung Radiation in the Electron Beams of a NEPTUN 10PC Linac using a Monte Carlo Method

    Directory of Open Access Journals (Sweden)

    Nasrollah Jabbari

    2009-03-01

    Full Text Available Introduction: In clinical electron beams, most of bremsstrahlung radiation is produced by various linac head structures. This bremsstrahlung radiation dose is influenced by the geometry and construction of every component of the linac treatment head structures. Thus, it can be expected that the amount of the contaminated photon dose due to bremsstrahlung radiation varies among different linacs, even for the same electron beam energy. The aims of this study were to simulate the NEPTUN 10PC linac electron beams and to calculate the photon contamination dose due to bremsstrahlung radiation in these beams using a Monte Carlo method. Materials and methods: A NEPTUN 10PC linac was simulated in its electron mode using the BEAMnrc code. This linac can provide three electron beam energies of 6, 8 and 10 MeV. Detailed information required for the simulation, including the geometry and materials of various components of the linac treatment head, was provided by the vender. For all simulations, the cut-off energies for electron and photon transport were set at ECUT=0.521 MeV and PCUT=0.010 MeV, respectively. The KS statistical test was used for validation of the simulated models. Then, relevant bremsstrahlung radiation doses for the three electron beam energies of the linac were calculated for the reference field using the Monte Carlo method.   Results: The KS test showed a good agreement between the calculated values (resulting from the simulations and the measured ones. The results showed that the amount of contaminated photon dose due to bremsstrahlung radiation from various components of the simulated linac at the surface of the phantom was between 0.2%-0.5% of the maximum dose for the three electron beam energies. Conclusion:  Considering the good agreement between the measured and simulated data, it can be concluded that the simulation method as well as the calculated bremsstrahlung doses have been made at a good level of accuracy and precision

  2. Impact of two-way air flow due to temperature difference on preventing the entry of outdoor particles using indoor positive pressure control method.

    Science.gov (United States)

    Chen, Chun; Zhao, Bin; Yang, Xudong

    2011-02-28

    Maintaining positive pressure indoors using mechanical ventilation system is a popular control method for preventing the entry of outdoor airborne particles. The idea is, as long as the supply air flow rate is larger than return air flow rate, the pressure inside the ventilated room should be positive since the superfluous air flow must exfiltrate from air leakages or other openings of the room to the outdoors. Based on experimental and theoretical analyses this paper aims to show the impact of two-way air flow due to indoor/outdoor temperature difference on preventing the entry of outdoor particles using positive pressure control method. The indoor positive pressure control method is effective only when the size of the opening area is restricted to a certain level, opening degree less than 30° in this study, due to the two-way air flow effect induced by differential temperature. The theoretical model was validated using the experimental data. The impacts of two-way air flow due to temperature difference and the supply air flow rate were also analyzed using the theoretical model as well as experimental data. For real houses, it seems that the idea about the positive pressure control method for preventing the entry of outdoor particles has a blind side.

  3. On the reduction of internal radiation doses due to the ingestion of CS-137 in areas contaminated by the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Hill, P.; Schlager, M.; Vogel, V.; Hille, R. [Forschungszentrum Julich GmbH, Julich (Germany); Nesterenko, A.V.; Nesterenko, V.B. [BELRAD, Minsk, (Belarus)

    2006-07-01

    After the Chernobyl reactor accident wide areas of Belarus have been contaminated with radioactive fallout. The verification and documentation of the long-term development of radiation doses is still going on. A population group of special concern are the children living in contaminated regions. Of the two million Belarussian children, approximately 80000 live in regions contaminated after the Chernobyl accident by a {sup 137}Cs deposition of more than 185 kBq/m. A German-Belarussian project is investigating radiation doses of children in those regions since several years. In a recent paper [1] it has been shown, that the annual dose limit of 1 mSv/a is still exceeded in some cases, essentially due to high body burdens of Cs -137 as indicated by screening measurements with portable incorporation monitors. Means of dose reduction such as remediation of agricultural land had been investigated in the past and generally already contribute to a reduction of food contamination. Also the use of clean food and the control of food contamination has generally proven its effectiveness and the latter is exercised by official authorities and private initiatives. In situations, where this is not sufficient, the clarification of the usefulness of additional means, such as the cure-like application of pectin preparations, makes sense. A dose lowering effect is presumed by Belarussian and Ukrainian scientists. In the framework of the present German-Belarussian project special attention is given to the cure-like application of a Belarussian pectin-preparation (Vitapect). Vitapect consists of apple pectins with added vitamins, mineral nutrients and flavour substances. It is currently in use in Belarus in accordance with legal regulations and licensed by the Belarus authorities. In a placebo-controlled double-blind study, several groups of contaminated children were treated with Vitapect for a two -week period during their stay in a sanatorium. For comparison the same number of

  4. Analysis of an Air Conditioning Coolant Solution for Metal Contamination Using Atomic Absorption Spectroscopy: An Undergraduate Instrumental Analysis Exercise Simulating an Industrial Assignment

    Science.gov (United States)

    Baird, Michael J.

    2004-01-01

    A real-life analytical assignment is presented to students, who had to examine an air conditioning coolant solution for metal contamination using an atomic absorption spectroscopy (AAS). This hands-on access to a real problem exposed the undergraduate students to the mechanism of AAS, and promoted participation in a simulated industrial activity.

  5. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 5, Appendix A, Part 1, Field Investigation report

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    This report presents information related to the sampling of ground water at the Wright-Patterson Air Force Base. It is part of an investigation into possible ground water contamination. Information concerns well drilling/construction; x-ray diffraction and sampling; soil boring logs; and chain-of-custody records.

  6. Air-borne microbial contamination of surfaces in a UK dental clinic.

    Science.gov (United States)

    Decraene, Valérie; Ready, Derren; Pratten, Jonathan; Wilson, Michael

    2008-08-01

    Little is known about the number, type, or antibiotic resistance profiles, of air-borne microbes present in hospital settings yet such information is important in designing effective measures to reduce cross-infection. In this study settle plates were used to identify and quantify the air-borne microbes present in a dental clinic. All isolates were identified to species level using partial 16S ribosomal RNA gene sequencing and their susceptibility to ampicillin, chloramphenicol, erythromycin, gentamicin, penicillin, tetracycline or vancomycin was performed. The mean numbers of viable bacteria detected for each sampling occasion during periods of clinical activity and in the absence of such activity were 21.9 x 10(2 )cfu/m2/h and 2.3 x 10(2 )cfu/m2/h respectively. One hundred ninety-three distinct colony morphotypes, comprising 73 species, were isolated during the study and 48% of these were resistant to at least one antibiotic. The mean numbers of different morphotypes detected per sampling occasion were 14.3 and 5 during periods of clinical activity and inactivity respectively. Propionibacterium acnes, Micrococcus luteus and Staphylococcus epidermidis were frequently isolated regardless of whether any clinical activities were taking place. These findings highlight the importance of preventing surfaces from becoming reservoirs of antibiotic-resistant bacteria and thereby contributing to cross-infection in the dental clinic.

  7. Study on Decomposition of Indoor Air Contaminants by Pulsed Atmospheric Microplasma

    Directory of Open Access Journals (Sweden)

    Tomoya Kuwabara

    2012-10-01

    Full Text Available Decomposition of formaldehyde (HCHO by a microplasma reactor in order to improve Indoor Air Quality (IAQ was achieved. HCHO was removed from air using one pass through reactor treatment (5 L/min. From an initial concentration of HCHO of 0.7 ppm about 96% was removed in one pass treatment using a discharge power of 0.3 W provided by a high voltage amplifier and a Marx Generator with MOSFET switches as pulsed power supplies. Moreover microplasma driven by the Marx Generator did not generate NOx as detected by a chemiluminescence NOx analyzer. In the case of large volume treatment the removal ratio of HCHO (initial concentration: 0.5 ppm after 60 minutes was 51% at 1.2 kV when using HV amplifier considering also a 41% natural decay ratio of HCHO. The removal ratio was 54% at 1.2 kV when a Marx Generator energized the electrodes with a 44% natural decay ratio after 60 minutes of treatment.

  8. Study on decomposition of indoor air contaminants by pulsed atmospheric microplasma.

    Science.gov (United States)

    Shimizu, Kazuo; Kuwabara, Tomoya; Blajan, Marius

    2012-10-29

    Decomposition of formaldehyde (HCHO) by a microplasma reactor in order to improve Indoor Air Quality (IAQ) was achieved. HCHO was removed from air using one pass through reactor treatment (5 L/min). From an initial concentration of HCHO of 0.7 ppm about 96% was removed in one pass treatment using a discharge power of 0.3 W provided by a high voltage amplifier and a Marx Generator with MOSFET switches as pulsed power supplies. Moreover microplasma driven by the Marx Generator did not generate NOx as detected by a chemiluminescence NOx analyzer. In the case of large volume treatment the removal ratio of HCHO (initial concentration: 0.5 ppm) after 60 minutes was 51% at 1.2 kV when using HV amplifier considering also a 41% natural decay ratio of HCHO. The removal ratio was 54% at 1.2 kV when a Marx Generator energized the electrodes with a 44% natural decay ratio after 60 minutes of treatment.

  9. Mercury poisoning dentistry: high-level indoor air mercury contamination at selected dental sites.

    Science.gov (United States)

    Khwaja, Mahmood A; Abbasi, Maryam Shabbir

    2014-01-01

    Mercury (Hg), also known as quick silver, is an essential constituent of dental amalgam. It is a toxic substance of global concern. Children are more at risk from mercury poisoning which affects their neurological development and brain. In the past, a number of studies at dental sites in many countries have been carried out and reported. The present report briefly describes and discusses our recent investigations carried out at 34 dental sites (teaching institutions, hospitals and private clinics) in Pakistan. It is evident from the data that at many sites the indoor mercury vapor levels exceed far above the permissible limit recommended for safe physical and mental health. At these sites, public in general and the medical, paramedical staff and vulnerable population in particular, are at most serious risk to health resulting from exposure to toxic and hazardous mercury. To minimize such risk, some of the recommendations are, best in-house environmental practices for occupational health and safety, mercury contaminated waste reduction at source, mercury specific legislation and ratification of Minamata convention on mercury by Pakistan and other world governments at the earliest time possible.

  10. Advanced air distribution method combined with deodorant material for exposure reduction to bioeffluents contaminants in hospitals

    DEFF Research Database (Denmark)

    Bivolarova, Mariya Petrova; Mizutani, Chiyomi; Melikov, Arsen Krikor

    2015-01-01

    -bed hospital patient room at reduced background ventilation rare of 1.6 air changes per hour. The bed of the patient was equipped with the ventilated mattress (VM) having an exhaust opening from which bioeffluents generated from human body were sucked and discharged from the room. To enhance the pollutant......The separate and combined effect of a ventilated mattress and acid-treated activated carbon fibre (ACF) fabric on reducing the exposure to body generated gaseous pollutants in hospital environment was studied. Full-scale experiments were performed in a climate chamber furnished as a single...... removal, acid-treated activated carbon fibre material was used in some of the experiments in the form of patient’s cover. The simulated pollution source was ammonia gas released from the patient’s groins. The results show that when using the ventilated mattress the ammonia gas concentration in the room...

  11. In situ stabilization/solidification pilot testing of coal tar contaminated sediment focusing on air quality testing program, Sydney, Nova Scotia

    Energy Technology Data Exchange (ETDEWEB)

    Raphael, A. [AECOM, Calgary, AB (Canada); Hilchey, J. [AECOM, Sydney, NS (Canada)

    2010-07-01

    This paper presented the results of a pilot-scale demonstration project conducted to test air quality contaminant emissions at a remediation project in Sydney, Nova Scotia. In situ sediment solidification/stabilization (S/S) was selected as a remedial solutions for sediments in an estuarine pond contaminated with polycyclic aromatic hydrocarbons (PAHs). The aim of the air monitoring program was to determine the emission rates of sediment contaminants that became airborne during remediation activities and to monitor the off-site environmental impacts of the emissions. The pilot project included driving interlocking steel sheet pile (SSP) through the sediment into the underlying natural soils, removing overlying water, homogenizing the sediment, and mixing S/S reagents into the sediment over a period of 4 days at 2 different sites. Air sampling equipment was used to monitor volumetric flow rates, benzene, naphthalene and particulate matter concentrations. Continuous real-time monitoring was used at downwind fence line perimeters and by time-weighted ambient air sampling at 6 community stations near the sites. Results of the study showed that the site-specific benzene and naphthalene emission rates were significantly lower than emission rates calculated using theoretical models. No exceedances of established community air quality limits were observed. 8 refs., 3 tabs., 3 figs.

  12. Effect of lead contamination of soils and air on its accumulation in pollen

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, W.H.O.; Bast-Cramer, W.B.

    1980-01-01

    Concentrations of heavy metals in the honey, derived from Aster tripolium was investigated. The lead content of pollen in Aster tripolium and Taraxacum officinale is mainly due to airborne lead. The accumulation of other heavy metals, such as zinc and copper, in pollen occurs mainly via a translocation process from roots to flowers. 14 references, 1 figure, 3 tables.

  13. Modeled effectiveness of ventilation with contaminant control devices on indoor air quality in a swine farrowing facility.

    Science.gov (United States)

    Anthony, T Renée; Altmaier, Ralph; Park, Jae Hong; Peters, Thomas M

    2014-01-01

    Because adverse health effects experienced by swine farm workers in concentrated animal feeding operations (CAFOs) have been associated with exposure to dust and gases, efforts to reduce exposures are warranted, particularly in winter seasons when exposures increase due to decreased ventilation. Simulation of air quality and operating costs for ventilating swine CAFO, including treating and recirculating air through a farrowing room, was performed using mass and energy balance equations over a 90-day winter season. System operation required controlling heater operation to achieve room temperatures optimal to ensure animal health (20 to 22.5 °C). Five air pollution control devices, four room ventilation rates, and five recirculation patterns were examined. Inhalable dust concentrations were easily reduced using standard industrial air pollution control devices, including a cyclone, filtration, and electrostatic precipitator. Operating ventilation systems at 0.94 m3 s(-1) (2000 cfm) with 75 to 100% recirculation of treated air from cyclone, electrostatic precipitator, and shaker dust filtration system achieves adequate particle control with operating costs under $1.00 per pig produced ($0.22 to 0.54), although carbon dioxide (CO2) concentrations approach 2000 ppm using in-room ventilated gas fired heaters. In no simulation were CO2 concentrations below industry recommended concentrations (1540 ppm), but alternative heating devices could reduce CO2 to acceptable concentrations. While this investigation does not represent all production swine farrowing barns, which differ in characteristics including room dimensions and swine occupancy, the simulation model and ventilation optimization methods can be applied to other production sites. This work shows that ventilation may be a cost-effective control option in the swine industry to reduce exposures.

  14. Groundwater contamination due to lead (Pb migrating from Richmond municipal landfill into Matsheumhlope aquifer: evaluation of a model using field observations

    Directory of Open Access Journals (Sweden)

    M. Kubare

    2010-10-01

    Full Text Available Disposal of solid waste in landfills is an economic option for many municipalities in developing countries where alternatives like incineration and composting are costly. However, groundwater pollution from the leachate generated within the landfill and migrating through the bottom liner material into the underlying groundwater aquifers remains a major public health concern. In our study, we evaluated the application of a mathematical model to determine the aerial extent of unacceptable groundwater contamination due to lead migrating from the Richmond landfill leachate into the underlying Matsheumhlope unconfined aquifer. A one-dimensional advection-dispersion model was applied to predict the down-gradient migration of lead into the aquifer. Linear sorption and first-order decay were considered as the dominant contaminant sink mechanisms for lead. Lead concentrations in the monitoring wells at the landfill site were used as the source term. The lead migration from the landfill was determined by water quality sampling from boreholes situated down-gradient of the landfill. The model simulations gave a good fit of the field results. The safe distance for potable water abstraction was determined to be 400 m, and the model simulations showed that the aerial extent of the pollution will increase with time. The model is most sensitive to the partition coefficient, hydraulic conductivity and longitudinal dispersivity, whilst it exhibits no sensitivity to the lead decay coefficient.

  15. Is there a risk for the aquatic environment due to the existence of emerging organic contaminants in treated domestic wastewater? Greece as a case-study.

    Science.gov (United States)

    Thomaidi, Vasiliki S; Stasinakis, Athanasios S; Borova, Viola L; Thomaidis, Nikolaos S

    2015-01-01

    The ecological threat associated with emerging pollutants detected in wastewater was estimated in country level. Treated wastewater was analyzed for pharmaceuticals and illicit drugs; whereas the concentrations of all emerging contaminants determined in Greek Sewage Treatment Plants were recorded through literature review. Toxicity data was collected after literature review or using ECOSAR and risk quotients (RQs) were calculated for treated wastewater and 25 Greek rivers, for 3 different aquatic organisms (fish, daphnia magna, algae). According to the results, monitoring data was available for 207 micropollutants belonging to 8 different classes. RQ>1 was calculated for 30 compounds in secondary treated wastewater. Triclosan presented RQ>1 (in algae) for all studied rivers; decamethylcyclopentasilane (in daphnia magna), caffeine (in algae) and nonylphenol (in fish) presented RQ>1 in rivers with dilution factors (DF) equal or lower to 1910, 913 and 824, respectively. The class of emerging contaminants that present the greatest threat due to single or mixture toxicity was endocrine disrupters. The mixture of microcontaminants seems to pose significant ecological risk, even in rivers with DF equal to 2388. Future national monitoring programs should include specific microcontaminants that seem to possess environment risk to surface water.

  16. Characterization of microbial contamination in United States Air Force aviation fuel tanks.

    Science.gov (United States)

    Rauch, Michelle E; Graef, Harold W; Rozenzhak, Sophie M; Jones, Sharon E; Bleckmann, Charles A; Kruger, Randell L; Naik, Rajesh R; Stone, Morley O

    2006-01-01

    Bacteria and fungi, isolated from United States Air Force (USAF) aviation fuel samples, were identified by gas chromatograph fatty acid methyl ester (GC-FAME) profiling and 16S or 18S rRNA gene sequencing. Thirty-six samples from 11 geographically separated USAF bases were collected. At each base, an above-ground storage tank, a refueling truck, and an aircraft wing tank were sampled at the lowest sample point, or sump, to investigate microbial diversity and dispersion within the fuel distribution chain. Twelve genera, including four Bacillus species and two Staphylococcus species, were isolated and identified. Bacillus licheniformis, the most prevalent organism isolated, was found at seven of the 11 bases. Of the organisms identified, Bacillus sp., Micrococcus luteus, Sphinogmonas sp., Staphylococcus sp., and the fungus Aureobasidium pullulans have previously been isolated from aviation fuel samples. The bacteria Pantoea ananatis, Arthrobacter sp., Alcaligenes sp., Kocuria rhizophilia, Leucobacter komagatae, Dietza sp., and the fungus Discophaerina fagi have not been previously reported in USAF aviation fuel. Only at two bases were the same organisms isolated from all three sample points in the fuel supply distribution chain. Isolation of previously undocumented organisms suggests either, changes in aviation fuel microbial community in response to changes in aviation fuel composition, additives and biocide use, or simply, improvements in isolation and identification techniques.

  17. Treatment of Perchlorate-Contaminated Groundwater Using Highly-Selective, Regenerable Anion-Exchange Resins at Edwards Air Force Base

    Energy Technology Data Exchange (ETDEWEB)

    Gu, B.

    2003-05-30

    Selective ion exchange is one of the most effective treatment technologies for removing low levels of perchlorate (ClO{sub 4}{sup -}) from contaminated water because of its high efficiency without adverse impacts on the water quality caused by adding or removing any chemicals or nutrients. This report summarizes both the laboratory and a field pilot-scale studies to determine the ability and efficiency of the bifunctional synthetic resins to remove ClO{sub 4}{sup -} from the contaminated groundwater at the Edwards Air Force Base in California. Regeneration of the resins after groundwater treatment was also evaluated using the FeCl{sub 3}-HCl regeneration technique recently developed at Oak Ridge National Laboratory. On the basis of this study, the bifunctional resin, D-3696 was found to be highly selective toward ClO{sub 4}{sup -} and performed much better than one of the best commercial nitrate-selective resins (Purolite A-520E) and more than an order of magnitude better than the Purolite A-500 resin (with a relatively low selectivity). At an influent concentration of {approx} 450 {micro}g/L ClO{sub 4}{sup -} in groundwater, the bifunctional resin bed treated {approx} 40,000 empty bed volumes of groundwater before a significant breakthrough of ClO{sub 4}{sup -} occurred. The presence of relatively high concentrations of chloride and sulfate in site groundwater did not appear to affect the ability of the bifunctional resin to remove ClO{sub 4}{sup -}. However, the presence of high iron or iron oxyhydroxides and/or biomass in groundwater caused a significant fouling of the resin beds and greatly influenced the effectiveness in regenerating the resins sorbed with ClO{sub 4}{sup -}. Under such circumstances, a prefilter ({approx} 0.5-1 {micro}m) was found to be necessary to remove these particulates and to reduce the risk of fouling of the resin beds. Without significant fouling, the resin bed could be effectively regenerated by the FeCl{sub 3} displacement technique

  18. Organochlorine pesticides in surface soils from obsolete pesticide dumping ground in Hyderabad City, Pakistan: contamination levels and their potential for air-soil exchange.

    Science.gov (United States)

    Alamdar, Ambreen; Syed, Jabir Hussain; Malik, Riffat Naseem; Katsoyiannis, Athanasios; Liu, Junwen; Li, Jun; Zhang, Gan; Jones, Kevin C

    2014-02-01

    This study was conducted to examine organochlorine pesticides (OCPs) contamination levels in the surface soil and air samples together with air-soil exchange fluxes at an obsolete pesticide dumping ground and the associated areas from Hyderabad City, Pakistan. Among all the sampling sites, concentrations of OCPs in the soil and air samples were found highest in obsolete pesticide dumping ground, whereas dominant contaminants were dichlorodiphenyltrichloroethane (DDTs) (soil: 77-212,200 ng g(-1); air: 90,700 pg m(-3)) and hexachlorocyclohexane (HCHs) (soil: 43-4,090 ng g(-1); air: 97,400 pg m(-3)) followed by chlordane, heptachlor and hexachlorobenzene (HCB). OCPs diagnostic indicative ratios reflect historical use as well as fresh input in the study area. Moreover, the air and soil fugacity ratios (0.9-1.0) at the dumping ground reflecting a tendency towards net volatilization of OCPs, while at the other sampling sites, the fugacity ratios indicate in some cases deposition and in other cases volatilization. Elevated concentrations of DDTs and HCHs at pesticide dumping ground and its surroundings pose potential exposure risk to biological organisms, to the safety of agricultural products and to the human health. Our study thus emphasizes the need of spatio-temporal monitoring of OCPs at local and regional scale to assess and remediate the future adverse implications.

  19. Microbial contamination of central supply systems for medical air Contaminação microbiana dos sistemas centrais de abastecimento de ar medicinal

    Directory of Open Access Journals (Sweden)

    Carolina Machado Andrade

    2003-11-01

    Full Text Available There are many standards and recommendations for breathing air quality associated with respiratory protection equipment, but little has been done regarding the possible microbial contamination of medical air. The present study demonstrates quantitatively and qualitatively that pipelines might be incriminated as source of microbial contamination of compressed and synthetic air for medical use. Air samples were drawn into an especially pressure-resistant device and the bacterial and fungi contents were identified after growth on agar plates. The bacterial flora isolated from peripheral air outlets was virtually the same as that found in the central air-generating installations, consisting of a mixture of pathogens and normal skin bacteria. Several factors contributing to microbial contamination of medical air are mentioned and preventive measures are discussed.Existem vários padrões e recomendações para a qualidade do ar respirável relacionado aos equipamentos de proteção respiratória, mas pouco tem sido feito em relação a uma possível contaminação microbiana do ar medicinal. O presente trabalho demonstra quantitativa e qualitativamente que as linhas de ar estão relacionadas à contaminação microbiológica do ar comprimido e ar sintético para uso medicinal. Amostras de ar foram coletadas por um equipamento especialmente resistente a pressão, e o conteúdo bacteriano e fúngico foi identificado após crescimento em placa. A flora bacteriana isolada tanto dos sistema periféricos de ar foi virtualmente a mesma encontrada nas instalações centralizadas, sendo uma mistura de patógenos e bactérias normais da pele. Vários fatores contribuintes para a contaminação microbiana do ar medicinal e medidas preventivas são discutidas.

  20. Impacts of rainfall and air temperature variations due to climate change upon hydrological characteristics: a case study

    Science.gov (United States)

    Rainfall and air temperature variations resulting from climate change are important driving forces to alter hydrologic processes in watershed ecosystems. This study investigated impacts of past and potential future rainfall and air temperature variations upon water discharge, water outflow (from th...

  1. Integrating a MRI scanner with a 6 MV radiotherapy accelerator: dose increase at tissue-air interfaces in a lateral magnetic field due to returning electrons

    Energy Technology Data Exchange (ETDEWEB)

    Raaijmakers, A J E; Raaymakers, B W; Lagendijk, J J W [Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht (Netherlands)

    2005-04-07

    In the framework of the development of the integration of a MRI-scanner with a linear accelerator, the influence of a lateral, magnetic field on the dose distribution has to be determined. Dose increase is expected at tissue-air boundaries, due to the electron return effect (ERE): electrons entering air will describe a circular path and return into the phantom causing extra dose deposition. Using IMRT with many beam directions, this exit dose will not constitute a problem. Dose levels behind air cavities will decrease because of the absence of electrons crossing the cavity. The ERE has been demonstrated both by simulation and experiment. Monte Carlo simulations are performed with GEANT4, irradiating a water-air-water phantom in a lateral magnetic field. Also an air tube in water has been simulated, resulting in slightly twisted regions of dose increase and decrease. Experimental demonstration is achieved by film measurement in a perspex-air-perspex phantom in an electromagnet. Although the ERE causes dose increase before air cavities, relatively flat dose profiles can be obtained for the investigated cases using opposite beam configurations. More research will be necessary whether this holds for more realistic geometries with the use of IMRT and whether the ERE can be turned to our advantage when treating small tumour sites at air cavities.

  2. Association between air pollution and daily mortality and hospital admission due to ischaemic heart diseases in Hong Kong

    Science.gov (United States)

    Tam, Wilson Wai San; Wong, Tze Wai; Wong, Andromeda H. S.

    2015-11-01

    Ischaemic heart disease (IHD) is one of the leading causes of death worldwide. The effects of air pollution on IHD mortalities have been widely reported. Fewer studies focus on IHD morbidities and PM2.5, especially in Asia. To explore the associations between short-term exposure to air pollution and morbidities and mortalities from IHD, we conducted a time series study using a generalized additive model that regressed the daily numbers of IHD mortalities and hospital admissions on daily mean concentrations of the following air pollutants: nitrogen dioxide (NO2), particulate matter with an aerodynamic diameter less than 10 μm (PM10), particulate matter with an aerodynamic diameter less than 2.5 μm (PM2.5), ozone (O3), and sulfur dioxide (SO2). The relative risks (RR) of IHD deaths and hospital admissions per 10 μg/m3 increase in the concentration of each air pollutant were derived in single pollutant models. Multipollutant models were also constructed to estimate their RRs controlling for other pollutants. Significant RRs were observed for all five air pollutants, ranging from 1.008 to 1.032 per 10 μg/m3 increase in air pollutant concentrations for IHD mortality and from 1.006 to 1.021 per 10 μg/m3 for hospital admissions for IHD. In the multipollutant model, only NO2 remained significant for IHD mortality while SO2 and PM2.5 was significantly associated with hospital admissions. This study provides additional evidence that mortalities and hospital admissions for IHD are significantly associated with air pollution. However, we cannot attribute these health effects to a specific air pollutant, owing to high collinearity between some air pollutants.

  3. [Environmental investigation of ground water contamination at Wright- Patterson Air Force Base, Ohio]. Volume 4, Health and Safety Plan (HSP); Phase 1, Task 4 Field Investigation report: Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This Health and Safety Plan (HSP) was developed for the Environmental Investigation of Ground-water Contamination Investigation at Wright-Patterson Air Force Base near Dayton, Ohio, based on the projected scope of work for the Phase 1, Task 4 Field Investigation. The HSP describes hazards that may be encountered during the investigation, assesses the hazards, and indicates what type of personal protective equipment is to be used for each task performed. The HSP also addresses the medical monitoring program, decontamination procedures, air monitoring, training, site control, accident prevention, and emergency response.

  4. The frequency of chromosomal aberrations in sheep from the area contaminated by depleted uranium during NATO air strikes in 1999

    Directory of Open Access Journals (Sweden)

    Fišter Svetlana L.

    2014-01-01

    Full Text Available This paper presents the results of cytogenetic studies in sheep from the region of Bujanovac that was contaminated by depleted uranium during the NATO air strikes in 1999. The study was conducted on sheep blood lymphocytes, in order to determine the frequency of chromosomal aberrations and to assess the presence of genetic risk as a result of the possible impact of depleted uranium. Blood samples for lymphocyte cultures were taken at random from the 20 animals of the households in the village of Borovac, near Bujanovac. The animals were chosen because they were pastured, fed, and watered in the NATO bombing area. With the purpose of comparing the results two control groups were cytogenetically analyzed, each consisted of 20 sheep from Zemun and Ovča, two northern localities that were not contaminated with depleted uranium. The established structural chromosomal changes were of breaks and gap types, and their frequencies in sheep of all surveyed localities were within the range of basic level values that are commonly found in the sheep lymphocyte cultures analyses. Significant differences are apparent between the values defined in the sheep from Bujanovac compared to those obtained in the sheep from the northern locality (Zemun, probably as a result of breeding of animals in the farm conditions and their being less exposed to the impact of environmental agents. There were neither elevated values of polyploid and aneuploid cells nor significant differences between the sites. According to earlier known data, depleted uranium was below the detection limit of the method applied both in the soil and feed given to cytogenetically analyzed animals. Based on the low-level changes that are in the range of the basic level changes, commonly observed in sheep lymphocytes control cultures, it cannot be said with certainty that it was depleted uranium that caused the changes, or that it is wide-spread in the region of Bujanovac. [Projekat Ministarstva nauke

  5. Steam and hot air injection for thermal rehabilitation of contaminated sites; Wasserdampf- und Heissluftinjektion zur thermischen Sanierung kontaminierter Standorte

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, R.

    2001-07-01

    Thermal in situ rehabilitation technologies are a promising alternative to conventional methods of cleaning up contaminated sites. The fact that an increase in temperature changes the physical properties of materials makes it possible, in principle, to release large quantities of pollutants within short time periods. The use of pure steam or steam/air mixtures as fluid thermal carriers permits converting subterranean non-aqueous-phase pollutants into the gas phase through increased vapour pressure and transporting them to the surface by means of soil air aspiration for further treatment. The purpose of the present two-stage research project was to systematically develop a thermal in situ rehabilitation technology using steam as fluid heat carrier and use it for land rehabilitation operations on a pilot basis. In the first, fundamental project phase aspects of heat transport (Faerber, 1997) and pollutant behaviour (Betz, 1998)in homogenous porous media upon pure steam injection were explored at a laboratory and technical scale using containers of different sizes (1D, 2D, 3D). The results were used to derive application criteria for this technology. [German] Thermische In-situ-Sanierungstechnologien stellen bei der Reinigung kontaminierter Standorte eine vielversprechende Alternative zu konventionellen Verfahren dar. Die Veraenderung physikalischer Stoffeigenschaften mit steigender Temperatur ermoeglicht grundsaetzlich hohe Schadstoffaustraege innerhalb kurzer Zeitraeume. Beim Einsatz von reinem Wasserdampf oder Wasserdampf-Luft-Gemischen als Waermetraegerfluid koennen im Untergrund in nicht waessriger Phase vorliegende Schadstoffe hauptsaechlich wegen der erhoehten Dampfdruecke in die Gasphase ueberfuehrt, ueber eine Bodenluftabsaugung an die Oberflaeche transportiert und dann einer weiteren Behandlung zugefuehrt werden. Zielsetzung eines zweistufigen Forschungsvorhabens war die systematische Entwicklung einer thermischen In-situ-Sanierungstechnologie unter

  6. The quality of air pollutant concentrations in Kermanshah emphasizing PM10 due to the occurrence of dust (2011-2013

    Directory of Open Access Journals (Sweden)

    Meghdad Pirsaheb

    2015-02-01

    Full Text Available Particulate matter is one of the important parameters in air pollutant standard index. 1095 samples were taken during three years and various seasons from five stations belonging to Kermanshah Environment Protection Agency. The results showed that particulate matter concentration was in the range of standard conditions in 67.5% of the days of the year, and it was in the range of dangerous conditions in 1.6% of the days of the year. Spring season and April month had the worst air quality in terms of PM10 concentration, which can be attributed to the incidence and intensity of dust phenomenon during this time.

  7. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 3, Appendix A, Draft standard operating procedures and elements: Sampling and Analysis Plan (SAP): Phase 1, Task 4, Field Investigation, Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.

  8. Development of a Computer-Based Air Force Installation Restoration Workstation for Contaminant Modeling and Decision-Making

    Science.gov (United States)

    1994-01-01

    suggests no risk of contamination, no information is provided as to the certainty of this conclusion. The recommended alternativo is to explicitly consider...granular materials with some sorption capacity. It is a less significant factor in fractured materials or cavernous rock , where contamination is likely

  9. Arctic smoke record high air pollution levels in the European Arctic due to agricultural fires in Eastern Europe

    Science.gov (United States)

    Stohl, A.; Berg, T.; Burkhart, J. F.; Fjæraa, A. M.; Forster, C.; Herber, A.; Hov, Ø.; Lunder, C.; McMillan, W. W.; Oltmans, S.; Shiobara, M.; Simpson, D.; Solberg, S.; Stebel, K.; Ström, J.; Tørseth, K.; Treffeisen, R.; Virkkunen, K.; Yttri, K. E.

    2006-10-01

    In spring 2006, the European Arctic was abnormally warm, setting new historical temperature records. During this warm period, smoke from agricultural fires in Eastern Europe intruded into the European Arctic and caused the most severe air pollution episodes ever recorded there. This paper confirms that biomass burning (BB) was indeed the source of the observed air pollution, studies the transport of the smoke into the Arctic, and presents an overview of the observations taken during the episode. Fire detections from the MODIS instruments aboard the Aqua and Terra satellites were used to estimate the BB emissions. The FLEXPART particle dispersion model was used to show that the smoke was transported to Spitsbergen and Iceland, which was confirmed by MODIS retrievals of the aerosol optical depth (AOD) and AIRS retrievals of carbon monoxide (CO) total columns. Concentrations of halocarbons, carbon dioxide and CO, as well as levoglucosan and potassium, measured at Zeppelin mountain near NyÅlesund, were used to further corroborate the BB source of the smoke at Spitsbergen. The ozone (O3) and CO concentrations were the highest ever observed at the Zeppelin station, and gaseous elemental mercury was also enhanced. A new O3 record was also set at a station on Iceland. The smoke was strongly absorbing - black carbon concentrations were the highest ever recorded at Zeppelin -, and strongly perturbed the radiation transmission in the atmosphere: aerosol optical depths were the highest ever measured at NyÅlesund. We furthermore discuss the aerosol chemical composition, obtained from filter samples, as well as the aerosol size distribution during the smoke event. Photographs show that the snow at a glacier on Spitsbergen became discolored during the episode and, thus, the snow albedo was reduced. Samples of this polluted snow contained strongly enhanced levels of potassium, sulphate, nitrate and ammonium ions, thus relating the discoloration to the deposition of the smoke

  10. Investigation of levels in ambient air near sources of Polychlorinated Biphenyls (PCBs) in Kanpur, India, and risk assessment due to inhalation.

    Science.gov (United States)

    Goel, Anubha; Upadhyay, Kritika; Chakraborty, Mrinmoy

    2016-05-01

    Polychlorinated biphenyls (PCBs) are a class of organic compounds listed as persistent organic pollutant and have been banned for use under Stockholm Convention (1972). They were used primarily in transformers and capacitors, paint, flame retardants, plasticizers, and lubricants. PCBs can be emitted through the primary and secondary sources into the atmosphere, undergo long-range atmospheric transport, and hence have been detected worldwide. Reported levels in ambient air are generally higher in urban areas. Active sampling of ambient air was conducted in Kanpur, a densely populated and industrialized city in the Indo-Gangetic Plain, for detection of 32 priority PCBs, with the aim to determine the concentration in gas/particle phase and assess exposure risk. More than 50 % of PCBs were detected in air. Occurrence in particles was dominated by heavier congeners, and levels in gas phase were below detection. Levels determined in this study are lower than the levels in Coastal areas of India but are at par with other Asian countries where majority of sites chosen for sampling were urban industrial areas. Human health risk estimates through air inhalation pathway were made in terms of lifetime average daily dose (LADD) and incremental lifetime cancer risks (ILCR). The study found lower concentrations of PCBs than guideline values and low health risk estimates through inhalation within acceptable levels, indicating a minimum risk to the adults due to exposure to PCBs present in ambient air in Kanpur.

  11. [Air quality monitoring on the International Space Station].

    Science.gov (United States)

    Pakhomova, A A; Mukhamedieva, L N; Mikos, K N

    2006-01-01

    Chemical contamination of air in space cabins occurs mainly due to permanent offgassing of equipment and materials, and leaks. Methods and means of qualitative and quantitative air monitoring on the ISS are powerful enough as for routine so emergency (e.g. local fire, toxic leak) air control. The ISS air quality has suited to the adopted standards and crew safety requirements. Yet, there is a broad field of action toward improvement of the space cabin air monitoring.

  12. Are the residents of former Yugoslavia still exposed to elevated PCB levels due to the Balkan wars? Part 1: Air sampling in Croatia, Serbia, Bosnia and Herzegovina.

    Science.gov (United States)

    Klánová, Jana; Kohoutek, Jirí; Kostrhounová, Romana; Holoubek, Ivan

    2007-08-01

    Persistent organic pollutants (POPs) spilled into the environment as a result of damaged industrial and military targets, natural resources, and infrastructure during the Balkan wars still pose a problem several years later. The aim of this project was to investigate an extent to which the residents of former Yugoslavia are exposed to elevated levels of POPs as a consequence of the wars. The atmospheric as well as the soil levels of PCBs, OCPs and PAHs were determined in Croatia, Serbia, Bosnia and Herzegovina during five high volume air sampling campaigns in 2003 and 2004. A considerable contamination of several sites was detected (PCB concentrations in the atmosphere ranged between 67 pg m(-3) and 40 ng m(-3) for the sum of 7 indicator congeners) and the levels are reported in this article.

  13. Radioactive contamination of nest materials of the Eurasian Tree Sparrow Passer montanus due to the Fukushima nuclear accident: The significance in the first year.

    Science.gov (United States)

    Matsui, Shin; Kasahara, Satoe; Morimoto, Gen; Mikami, Osamu K; Watanabe, Mamoru; Ueda, Keisuke

    2015-11-01

    The 2011 Fukushima nuclear accident contaminated large areas of eastern and northeastern Japan, releasing vast amounts of radiation. Here we investigated radioactive contamination of the nest materials of the Eurasian Tree Sparrow Passer montanus from the breeding season of 2011 directly after the accident to the next breeding season of 2012 at two sites. In Tokyo (222 km southwest of the plant), ambient dose rates in the nestboxes were lower than those in Ibaraki (175 km southwest of the plant), where the levels of 2011 were higher than those of 2012. Further, the amount of radioactive Cs in each nest increased with the increase in nest weight, with a higher increment at Ibaraki than at Tokyo. These data suggested higher nest contamination levels in the breeding season directly after a nuclear accident than in later seasons, and an increment of nest contamination levels via nest materials of birds.

  14. Quantitative risk assessment of listeriosis-associated deaths due to Listeria monocytogenes contamination of deli meats originating from manufacture and retail.

    Science.gov (United States)

    Pradhan, Abani K; Ivanek, Renata; Gröhn, Yrjö T; Bukowski, Robert; Geornaras, Ifigenia; Sofos, John N; Wiedmann, Martin

    2010-04-01

    The objective of this study was to estimate the relative risk of listeriosis-associated deaths attributable to Listeria monocytogenes contamination in ham and turkey formulated without and with growth inhibitors (GIs). Two contamination scenarios were investigated: (i) prepackaged deli meats with contamination originating solely from manufacture at a frequency of 0.4% (based on reported data) and (ii) retail-sliced deli meats with contamination originating solely from retail at a frequency of 2.3% (based on reported data). Using a manufacture-to-consumption risk assessment with product-specific growth kinetic parameters (i.e., lag phase and exponential growth rate), reformulation with GIs was estimated to reduce human listeriosis deaths linked to ham and turkey by 2.8- and 9-fold, respectively, when contamination originated at manufacture and by 1.9- and 2.8-fold, respectively, for products contaminated at retail. Contamination originating at retail was estimated to account for 76 and 63% of listeriosis deaths caused by ham and turkey, respectively, when all products were formulated without GIs and for 83 and 84% of listeriosis deaths caused by ham and turkey, respectively, when all products were formulated with GIs. Sensitivity analyses indicated that storage temperature was the most important factor affecting the estimation of per annum relative risk. Scenario analyses suggested that reducing storage temperature in home refrigerators to consistently below 7 degrees C would greatly reduce the risk of human listeriosis deaths, whereas reducing storage time appeared to be less effective. Overall, our data indicate a critical need for further development and implementation of effective control strategies to reduce L. monocytogenes contamination at the retail level.

  15. Air-borne contact dermatitis due to Chrysanthemum with true cross sensitivity to Parthenium hysterophorus and Xanthium strumarium

    Directory of Open Access Journals (Sweden)

    Pasricha J

    1992-01-01

    Full Text Available A 60-year old man living in Srinagar (Jammu and Kashmir had air-borne contact dermatitis for last 10 years. He had never traveled to any other part of the country where Parthenium hysterophorus or Xanthium strumarium are prevalent but he used to cultivate chrysanthemums. Patch tests with standardized extracts of various plants revealed the strongest reaction with Chrysanthemum, while the reactions with Xanthium strumarium and Parthenium hysterophorus were also positive but milder. This seems to be a case of primary sensitivity to Chrysanthemum with cross sensitivity to Xanthium strumarium and Parthenium hysterophorus.

  16. Measurement methodology of vegetable samples from an area affected by residual contamination due to uranium mining sterile; Metodologia de medida de muestras vegetales procedentes de un terreno afectado por contaminacion residual debida a esteriles de mineria de uranio

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, N.; Suarez, J. A.; Yague, L.; Ortiz Gandia, M. I.; Marijuan, M. J.; Garcia, E.; Ortiz, T.; Alvarez, A.

    2013-07-01

    This paper presents the methodology established for radiological characterization of plant material generated during the first stage of the realization of a movement of land in an area of land affected by residual contamination due to the burial of sterile of uranium mining. (Author)

  17. Analysis and evaluation methods for chemical contaminants in clean room air; Kagaku osen no bunseki hyokaho clean room kukichu no kagaku osen busshitsu ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, T.

    1998-07-31

    As for, chemical contamination in a cleanroom air has taken up as a important problem. As the main source is building materials, after construction the execution of countermeasures is difficult. Out-gas evaluation and selection in building materials, chemical filters for removing specific organic matter and so on, are a large technical theme in the future and analytical techniques corresponding them become necessary. In this paper, analytical methods of airborne molecular contaminants (AMCs) are introduced. Main samples are AMCs in cleanroom atmosphere, on silicon wafer surface and out-gas from raw materials for cleanroom construction materials such as sealant, plastics and so on. Analytical methods consist of quantification of inorganic compounds, organic compounds and identification of abnormal spot with local/surface analysis. Various interesting findings with analytical data are obtained and investigated. 22 refs., 6 figs., 5 tabs.

  18. Changes in air quality and tropospheric composition due to depletion of stratospheric ozone and interactions with climate.

    Science.gov (United States)

    Tang, X; Wilson, S R; Solomon, K R; Shao, M; Madronich, S

    2011-02-01

    Air pollution will be directly influenced by future changes in emissions of pollutants, climate, and stratospheric ozone, and will have significant consequences for human health and the environment. UV radiation is one of the controlling factors for the formation of photochemical smog, which includes tropospheric ozone (O(3)) and aerosols; it also initiates the production of hydroxyl radicals (˙OH), which control the amount of many climate- and ozone-relevant gases (e.g., methane and HCFCs) in the atmosphere. Numerical models predict that future changes in UV radiation and climate will modify the trends and geographic distribution of ˙OH, thus affecting the formation of photochemical smog in many urban and regional areas. Concentrations of ˙OH are predicted to decrease globally by an average of 20% by 2100, with local concentrations varying by as much as a factor of two above and below current values. However, significant differences between modelled and measured values in a limited number of case studies show that chemistry of hydroxyl radicals in the atmosphere is not fully understood. Photochemically produced tropospheric ozone is projected to increase. If emissions of anthropogenic air pollutants from combustion of fossil fuels, burning of biomass, and agricultural activities continue to increase, concentrations of tropospheric O(3) will tend to increase over the next 20-40 years in certain regions of low and middle latitudes because of interactions of emissions, chemical processes, and climate change. Climate-driven increases in temperature and humidity will also increase production of tropospheric O(3) in polluted regions, but reduce it in more pristine regions. Higher temperatures tend to increase emissions of nitrogen oxides (NO(x)) from some soils and release of biogenic volatile organic compounds (VOCs) from vegetation, leading to greater background concentrations of ozone in the troposphere. The net effects of future changes in UV radiation

  19. The atmospheric distribution of contaminated air masses from the reactors in Fukushima Daiichi - nuclide spectra and dose reduction; Die atmosphaerische Ausbreitung kontaminierter Luftmassen aus den Reaktoren von Fukushima Daiichi - Nuklidspektrum und Dosisrekonstruktion

    Energy Technology Data Exchange (ETDEWEB)

    Zaehringer, Matthias [Bundesamt fuer Strahlenschutz, Freiburg (Germany); Gering, Florian [Bundesamt fuer Strahlenschutz, Oberschleissheim (Germany). Abt. Notfallschutz

    2015-06-01

    The compiled information is based on the data from the United Nations scientific committee on the effects of atomic radiation (UNSCEAR). Due to the earthquake and tsunami only few measurements have been performed during the first days after the reactor accidents in Fukushima Daiichi. In the vicinity of the nuclear power plant no radiation monitoring network comparable to the German IMIS was installed. There are only few data on the air contamination are available. Worldwide in CTBT stations measured activity data of Te-132 and Cs-137 are correlated with estimated data from reactor inventories. It is assumed that the complete rare earth inventories were released - available data of Xe-133 and Kr-85 are analyzed. The UNSCEAR estimation on radiological consequences has to use estimated source terms reconstructed data for the radionuclide migration.

  20. Sampling artifacts in active air sampling of semivolatile organic contaminants: Comparing theoretical and measured artifacts and evaluating implications for monitoring networks.

    Science.gov (United States)

    Melymuk, Lisa; Bohlin-Nizzetto, Pernilla; Prokeš, Roman; Kukučka, Petr; Klánová, Jana

    2016-10-01

    The effects of sampling artifacts are often not fully considered in the design of air monitoring with active air samplers. Semivolatile organic contaminants (SVOCs) are particularly vulnerable to a range of sampling artifacts because of their wide range of gas-particle partitioning and degradation rates, and these can lead to erroneous measurements of air concentrations and a lack of comparability between sites with different environmental and sampling conditions. This study used specially adapted filter-sorbent sampling trains in three types of active air samplers to investigate breakthrough of SVOCs, and the possibility of other sampling artifacts. Breakthrough volumes were experimentally determined for a range of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) in sampling volumes from 300 to 10,000 m(3), and sampling durations of 1-7 days. In parallel, breakthrough was estimated based on theoretical sorbent-vapor pressure relationships. The comparison of measured and theoretical determinations of breakthrough demonstrated good agreement between experimental and estimated breakthrough volumes, and showed that theoretical breakthrough estimates should be used when developing air monitoring protocols. Significant breakthrough in active air samplers occurred for compounds with vapor pressure >0.5 Pa at volumes Sample volumes between 700 and 10,000 m(3) may lead to breakthrough for compounds with vapor pressures between 0.005 and 0.5 Pa. Breakthrough is largely driven by sample volume and compound volatility (therefore indirectly by temperature) and is independent of sampler type. The presence of significant breakthrough at "typical" sampling conditions is relevant for air monitoring networks, and may lead to under-reporting of more volatile SVOCs.

  1. Study of Air Pollution Due to Plasma Cutting Process and Designing Local Ventilation System with Collector in Central Workshop of Mobarakeh Steel Company

    Directory of Open Access Journals (Sweden)

    Farideh Atabi

    2014-06-01

    Full Text Available Background & Objectives : Cutting leads to production of different hazardous agents such as fumes, particles, gases and vapors. In various studies, the effects of fumes, gases, and vapors on workers and environment have been proved. Meanwhile, cutting alloying plates with plasma cutting machine due to containing various alloy materials produces a lot of air pollution. Therefore, using the ventilation system to remove the mentioned pollution has always been noteworthy. Method: This study was performed on plasma cutting machine at Mobarakeh Steel Company. At first, according to ASTM the elements from alloy plates with optical emission spectrometry crm-35000-quantometery were detected, the air pollution from cutting the mentioned plates was sampled and measured using NIOSH 7300 method and according to the ACGIH:VS-72-20, VS-70-12, VS-70-11 VS-916 push-pull ventilation with bag filter collector was designed. Results: Results of sampling from pollution of cutting the alloy material, concentration of iron, lead and cadmium fumes were more than the standard limits. After calculation for push system, air flow volume of 195.163 cfm, outgoing air velocity of 5937.4 fpm and for pull system air flow volume of 12498 cfm, minimum duct velocity of 3000 fpm and velocity pressure of duct of 0.717 inwg, for fan, total pressure of 6.301 inwg, static pressure of 0.587 inwg and power of 20.65 Bhp and for collector with pulse jet cleaning system air to cloth ratio of 7 and dimensions of 6.88ft × 6.56ft × 9.84ft were obtained. Conclusion: The result of study indicated that push pull ventilation compared to other ventilation system s for plasma cutting has more efficiency and makes suitable control for pollution.

  2. PEM fuel cell cathode carbon corrosion due to the formation of air/fuel boundary at the anode

    Science.gov (United States)

    Tang, Hao; Qi, Zhigang; Ramani, Manikandan; Elter, John F.

    The impacts of unprotected start up and shut down on fuel cell performance degradation was investigated using both single cell and dual cell configurations. It was found that the air/fuel boundary developed at the anode side after a fuel cell shut down or during its restart caused extremely quick degradation of the cathode. The thickness, the electrochemical active surface area, and the performance of the cathode catalyst layer were significantly reduced. By using a dual cell configuration, cathode potential as high as two times of open circuit voltage was measured, and the corrosion current flowing externally between the two cells was detected and quantified. Carbon catalyst-support corrosion/oxidation at such a high potential was largely responsible for the accelerated fuel cell performance degradation.

  3. Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated groundwater at Beale Air Force Base in California

    Energy Technology Data Exchange (ETDEWEB)

    Bogen, K T; Daniels, J I; Hall, L C

    1999-09-01

    This study was designed to accomplish two objectives. The first was to provide to the US Air Force and the regulatory community quantitative procedures that they might want to consider using for addressing uncertainty and variability in exposure to better characterize potential health risk. Such methods could be used at sites where populations may now or in the future be faced with using groundwater contaminated with low concentrations of the chemical trichloroethylene (TCE). The second was to illustrate and explain the application of these procedures with respect to available data for TCE in ground water beneath an inactive landfill site that is undergoing remediation at Beale Air Force Base in California. The results from this illustration provide more detail than the more traditional conservative deterministic, screening-level calculations of risk, also computed for purposes of comparison. Application of the procedures described in this report can lead to more reasonable and equitable risk-acceptability criteria for potentially exposed populations at specific sites.

  4. Polychlorinated biphenyls (PCBs) in indoor air originating from sealants in contaminated and uncontaminated apartments within the same housing estate

    DEFF Research Database (Denmark)

    Frederiksen, Marie; Meyer, Harald William; Ebbehøj, Niels Erik;

    2012-01-01

    Twenty-four congeners of polychlorinated biphenyls (PCBs) were measured in 83 air samples and 20 elastic sealants samples of apartments with PCB-containing sealants. In addition, PCBs were measured in 21 air samples from reference apartments located in an uncontaminated section of the same estate...

  5. 空气细菌真菌污染的分级评价构建方法%Establishment of Assessment Method for Air Bacteria and Fungi Contamination

    Institute of Scientific and Technical Information of China (English)

    张华玲; 姚大军; 张雨; 方子梁

    2016-01-01

    In this paper, in order to settle existing problems in the assessment of air bacteria and fungi contamination, the indoor and outdoor air bacteria and fungi filed concentrations by impact method and settlement method in existing documents were collected and analyzed, then the goodness of chi square was used to test whether these concentration data obeyed normal distribution at the significant level of α = 0. 05, and combined with the 3σ principle of normal distribution and the current assessment standards, the suggested concentrations ranges of air microbial concentrations were determined. The research results could provide a reference for developing air bacteria and fungi contamination assessment standards in the future.%针对空气细菌真菌污染评价存在的不足,搜集整理现有研究文献中对室内外空气细菌和真菌的现场实测数据,利用拟合优度χ2检验法证明了在显著性水平α为0.05时,室内外空气细菌和真菌分别采用撞击法和沉降法的8组浓度数据均服从正态分布,并结合正态分布的3σ原则和现行评价标准,给出了可用于空气细菌真菌分级评价的浓度建议区间,研究成果可为将来制定空气细菌真菌污染的评价标准提供参考.

  6. (Contaminated soil)

    Energy Technology Data Exchange (ETDEWEB)

    Siegrist, R.L.

    1991-01-08

    The traveler attended the Third International Conference on Contaminated Soil, held in Karlsruhe, Germany. The Conference was a status conference for worldwide research and practice in contaminated soil assessment and environmental restoration, with more than 1500 attendees representing over 26 countries. The traveler made an oral presentation and presented a poster. At the Federal Institute for Water, Soil and Air Hygiene, the traveler met with Dr. Z. Filip, Director and Professor, and Dr. R. Smed-Hildmann, Research Scientist. Detailed discussions were held regarding the results and conclusions of a collaborative experiment concerning humic substance formation in waste-amended soils.

  7. Polychlorinated biphenyls (PCBs) in air and soil from a high-altitude pasture in the Italian Alps: evidence of CB-209 contamination.

    Science.gov (United States)

    Tremolada, Paolo; Guazzoni, Niccolò; Comolli, Roberto; Parolini, Marco; Lazzaro, Serena; Binelli, Andrea

    2015-12-01

    This study analyses the seasonal trend of polychlorinated biphenyls (PCB) concentrations in air and soil from a high-altitude mountain pasture in the Italian Alps. PCB concentrations in soil were generally comparable to background levels and were lower than those previously measured in the same area. Only CB-209 unexpectedly showed high concentrations with respect to the other congeners. GC-MS-MS identification was very clear, rising a new problem of increasing PCB contamination concerning only CB-209, which is not present in commercial mixtures used in the past in Italy and Europe. Considering all of the congeners, seasonal PCB trends were observed both in air and in soil that were related to the temperature and precipitation measured specifically in the study area. Highly significant relationships were found between the temperature-normalised concentrations in soil and the precipitation amounts. A north/south enrichment factor was present only in soil with rapid early summer re-volatilisation kinetics from soil to air and autumn re-deposition events from air to soil. Fugacity ratio calculations confirmed these trends. Surface soils respond rapidly to meteorological variables, while subsurface soils respond much more slowly. Seasonal trends were different for the northern and southern sides of the mountain. A detailed picture of the interactions among temperature, precipitation, mountain aspects and soil features was obtained.

  8. STROBE-Long-Term Exposure to Ambient Fine Particulate Air Pollution and Hospitalization Due to Peptic Ulcers.

    Science.gov (United States)

    Wong, Chit-Ming; Tsang, Hilda; Lai, Hak-Kan; Thach, Thuan-Quoc; Thomas, G Neil; Chan, King-Pan; Lee, Siu-Yin; Ayres, Jon G; Lam, Tai-Hing; Leung, Wai K

    2016-05-01

    Little is known about the effect of air pollution on the gastrointestinal (GI) system. We investigated the association between long-term exposures to outdoor fine particles (PM2.5) and hospitalization for peptic ulcer diseases (PUDs) in a large cohort of Hong Kong Chinese elderly.A total of 66,820 subjects aged ≥65 years who were enrolled in all 18 Government Elderly Health Service centers of Hong Kong participated in the study voluntarily between 1998 and 2001. They were prospectively followed up for more than 10 years. Annual mean exposures to PM2.5 at residence of individuals were estimated by satellite data through linkage with address details including floor level. All hospital admission records of the subjects up to December 31, 2010 were retrieved from the central database of Hospital Authority. We used Cox regression to estimate the hazard ratio (HR) for PUD hospitalization associated with PM2.5 exposure after adjustment for individual and ecological covariates.A total of 60,273 subjects had completed baseline information including medical, socio-demographic, lifestyle, and anthropometric data at recruitment. During the follow-up period, 1991 (3.3%) subjects had been hospitalized for PUD. The adjusted HR for PUD hospitalization per 10 μg/m of PM2.5 was 1.18 (95% confidence interval: 1.02-1.36, P = 0.02). Further analysis showed that the associations with PM2.5 were significant for gastric ulcers (HR 1.29; 1.09-1.53, P = 0.003) but not for duodenal ulcers (HR 0.98; 0.78 to 1.22, P = 0.81).Long-term exposures to PM2.5 were associated with PUD hospitalization in elder population. The mechanism underlying the PM2.5 in the development of gastric ulcers warrants further research.

  9. Containment Performance Evaluation of a Sodium Fire Event Due to Air Ingress into the Cover Gas Region of the Reactor Vessel in the PGSFR

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Sang June; Chang, Won-Pyo; Kang, Seok Hun; Choi, Chi-Woong; Yoo, Jin; Lee, Kwi Lim; Jeong, Jae-Ho; Lee, Seung Won; Jeong, Taekyeong; Ha, Kwi-Seok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Comparing with the light water reactor, sodium as a reactor coolant violently reacts with oxygen in the containment atmosphere. Due to this chemical reaction, heat generated from the combustion heat increases the temperature and pressure in the containment atmosphere. The structural integrity of the containment building which is a final radiological defense barrier is threaten. A sodium fire event in the containment due to air ingress into the cover gas region in the reactor vessel is classified as one of the design basis events in the PGSFR. This event comes from a leak or crack on the reactor upper closure header surface. It accompanys an event of the radiological fission products release to the inside the containment. In this paper, evaluation for the sodium fire and radiological influence due to air ingress into the cover gas region of the reactor vessel is described. To evaluate this event, the CONTAIN-LMR, MACCS-II and OR-IGEN-II codes are used. For the sodium pool fire event in the containment, the performance evaluation and radiological influence are carried out. In the thermal hydraulic aspects, the 1 cell containment yields the most conservative result. In this event, the maximum temperature and pressure in the containment are calculated 0.185 MPa, 280.0 .deg. C, respectively. The radiological dose at the EAB and LPZ are below the acceptance criteria specified in the 10CFR100.

  10. Performance of personalized ventilation in a room with an underfloor air distribution system: transport of contaminants between occupants

    DEFF Research Database (Denmark)

    Cermak, Radim; Melikov, Arsen Krikor

    2003-01-01

    Studies have documented that personalized ventilation, which provides clean air at each office workplace, is able to improve substantially the quality of air inhaled by occupants. However, the interaction between the airflow generated by personalized ventilation and the airflow pattern outside...... two occupants was examined using a tracer-gas. Two breathing thermal manikins were used to simulate occupants. The results show that the tested combination of personalized and underfloor ventilation was not able to decrease concentration of the human-produced airborne pollutants in air inhaled...

  11. Effects of warming on uptake and translocation of cadmium (Cd) and copper (Cu) in a contaminated soil-rice system under Free Air Temperature Increase (FATI).

    Science.gov (United States)

    Ge, Li-Qiang; Cang, Long; Liu, Hui; Zhou, Dong-Mei

    2016-07-01

    Global warming has received growing attentions about its potential threats to human in recent, however little is known about its effects on transfer of heavy metals in agro-ecosystem, especially for Cd in rice. Pot experiments were conducted to evaluate Cd/Cu translocation in a contaminated soil-rice system under Free Air Temperature Increase (FATI). The results showed that warming gradually decreased soil porewater pH and increased water-soluble Cd/Cu concentration, reduced formation of iron plaque on root surface, and thus significantly increased total uptake of Cd/Cu by rice. Subsequently, warming significantly promoted Cd translocation from root to shoot, and increased Cd distribution percentage in shoot, while Cu was not significantly affected. Enhanced Cd uptake and translocation synergistically resulted in higher rice grain contamination with increasing concentration from 0.27 to 0.65 and 0.14-0.40 mg kg(-1) for Indica and Japonica rice, respectively. However increase of Cu in brown grain was only attributed to its uptake enhancement under warming. Our study provides a new understanding about the food production insecurity of heavy metal contaminated soil under the future global warming.

  12. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 3, Sampling and analysis plan (SAP): Phase 1, Task 4, Field Investigation: Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    In April 1990, Wright-Patterson Air Force Base (WPAFB), initiated an investigation to evaluate a potential Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) removal action to prevent, to the extent practicable, the offsite migration of contaminated ground water from WPAFB. WPAFB retained the services of the Environmental Management Operations (EMO) and its principle subcontractor, International Technology Corporation (IT) to complete Phase 1 of the environmental investigation of ground-water contamination at WPAFB. Phase 1 of the investigation involves the short-term evaluation and potential design for a program to remove ground-water contamination that appears to be migrating across the western boundary of Area C, and across the northern boundary of Area B along Springfield Pike. Primarily, Task 4 of Phase 1 focuses on collection of information at the Area C and Springfield Pike boundaries of WPAFB. This Sampling and Analysis Plan (SAP) has been prepared to assist in completion of the Task 4 field investigation and is comprised of the Quality Assurance Project Plan (QAPP) and the Field Sampling Plan (FSP).

  13. Electrical Characteristics, Electrode Sheath and Contamination Layer Behavior of a Meso-Scale Premixed Methane-Air Flame Under AC/DC Electric Fields

    Institute of Scientific and Technical Information of China (English)

    CHEN Qi; YAN Limin; ZHANG Hao; LI Guoxiu

    2016-01-01

    Electrical characteristics of a nozzle-attached meso-scale premixed methane-air flame under low-frequency AC (0-4300 V,0-500 Hz) and DC (0-3300 V) electric fields were studied.Ⅰ-Ⅴ curves were measured under different experimental conditions to estimate the magnitude of the total current 100-102 μA,the electron density 1015-1016 m-3 and further the power dissipation ≤ 0.7 W in the reaction zone.At the same time,the meso-scale premixed flame conductivity 10-4-10-3 Ω-1.m-1 as a function of voltage and frequency was experimentally obtained and was believed to represent a useful order-of magnitnde estimate.Moreover,the influence of the collision sheath relating to Debye length (31-98 μm) and the contamination layer of an active electrode on measurements was discussed,based on the combination of simulation and theoretical analysis.As a result,the electrode sheath dimension was evaluated to less than 0.5 mm,which indicatcd a complex effect of the collisiou sheath on the current measurements.The surface contamination effect of an active electrode was further analyzed using the SEM imaging method,which showed elements immigration during the contamination layer formation process.

  14. Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated ground water at Beale Air Force Base in California

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, J I; Bogen, K T; Hall, L C

    1999-10-05

    Conservative deterministic, screening-level calculations of exposure and risk commonly are used in quantitative assessments of potential human-health consequences from contaminants in environmental media. However, these calculations generally are based on multiple upper-bound point estimates of input parameters, particularly for exposure attributes, and can therefore produce results for decision makers that actually overstate the need for costly remediation. Alternatively, a more informative and quantitative characterization of health risk can be obtained by quantifying uncertainty and variability in exposure. This process is illustrated in this report for a hypothetical population at a specific site at Beale Air Force Base in California, where there is trichloroethylene (TCE) contaminated ground water and a potential for future residential use. When uncertainty and variability in exposure were addressed jointly for this case, the 95th-percentile upper-bound value of individual excess lifetime cancer risk was a factor approaching 10 lower than the most conservative deterministic estimate. Additionally, the probability of more than zero additional cases of cancer can be estimated, and in this case it is less than 0.5 for a hypothetical future residential population of up to 26,900 individuals present for any 7.6-y interval of a 70-y time period. Clearly, the results from application of this probabilistic approach can provide reasonable and equitable risk-acceptability criteria for a contaminated site.

  15. ON THE RELATIONSHIP BETWEEN AMBIENT DOSE EQUIVALENT AND ABSORBED DOSE IN AIR IN THE CASE OF LARGE-SCALE CONTAMINATION OF THE ENVIRONMENT BY RADIOACTIVE CESIUM

    Directory of Open Access Journals (Sweden)

    V. P. Ramzaev

    2015-01-01

    Full Text Available One of the main aims of the study was an experimental determination of the conversion coefficient from ambient dose equivalent rate, Н*(10, to absorbed dose rate in air, D, in the case of radioactive contamination of the environment following the Chernobyl accident. More than 800 measurements of gamma-dose rates in air were performed at the typical locations (one-storey residential house, street, yard, kitchen-garden, ploughed field, undisturbed grassland, forest of rural settlements and their surroundings in the heavily contaminated areas of the Bryansk region, Russia in the period of 1996–2010. Five commercially available models of portable gamma-ray dosimeters were employed in the investigation. All tested dosimeters were included into the State register of approved measuring instruments of Russia. In all dosimeters, scintillation detectors are used as detection elements. A photon spectrometry technique is applied in the dosimeters to determine gamma dose rate in air. The dosimeters are calibrated in terms of exposure rate, X, absorbed dose rate in air, D, and ambient dose equivalent rate, Н*(10. A very good agreement was found between different dosimeters calibrated in the same units; the reading ratios were close to 1 and the correlation coefficients (Pearson’s or Spearman’s were higher than 0.99. The Н*(10/D ratio values were location-specific ranging from 1.23 Sv/Gy for undisturbed grasslands and forests to 1.47 Sv/Gy for wooden houses and asphalted streets. A statistically significant negative correlation (Spearman’s coefficient = -0.833; P<0.01; n=9 was found between the Н*(10/D ratio and the average energy of gamma-rays determined with a NaI(Tl-based gamma-ray monitor. For the whole area of a settlement and its surroundings, the average ratio of Н*(10 to D was calculated as 1.33 Sv/Gy. The overall conversion coefficient from ambient dose equivalent rate, Н*(10, to external effective dose rate, Ė, for adults was estimated

  16. On-site application of air cleaner emitting plasma ion to reduce airborne contaminants in pig building

    Science.gov (United States)

    Cho, Man Su; Ko, Han Jong; Kim, Daekeun; Kim, Ki Youn

    2012-12-01

    The objective of this field study is to evaluate temporal reduction efficiency of air cleaner emitting plasma ion on airborne pollutants emitted from pig building. The operation principle of air cleaner based on plasma ion is that hydrogen atoms and oxygen ions combine to form hydroperoxyl radicals (HOO-), which surround and attach to surface of airborne microorganisms and eliminate them by breaking the hydrogen bond in their protein structure. In gaseous pollutants, it was found that there is no reduction effect of the air cleaner on ammonia and hydrogen sulfide (p > 0.05). In particulate pollutants, the air cleaner showed mean 79%(±6.1) and 78%(±3.0) of reduction efficiency for PM2.5. and PM1, respectively, compared to the control without air cleaner (p 0.05). In biological pollutants, the mean reduction efficiencies for airborne bacteria and fungi by application of air cleaner were 22%(±6.6) and 25%(±8.7), respectively (p effect on PM2.5, PM1, airborne bacteria and airborne fungi among airborne pollutants distributed in pig building while it did not lead to significant reduction of ammonia and hydrogen sulfide.

  17. The impact of past and future climate change on global human mortality due to ozone and PM2.5 outdoor air pollution

    Science.gov (United States)

    Silva, R.; West, J.; Anenberg, S.; Lamarque, J.; Shindell, D. T.; Bergmann, D. J.; Berntsen, T.; Cameron-Smith, P. J.; Collins, B.; Ghan, S. J.; Josse, B.; Nagashima, T.; Naik, V.; Plummer, D.; Rodriguez, J. M.; Szopa, S.; Zeng, G.

    2012-12-01

    Climate change can adversely affect air quality, through changes in meteorology, atmospheric chemistry, and emissions. Future changes in air pollutant emissions will also profoundly influence air quality. These changes in air quality can affect human health, as exposure to ground-level ozone and fine particulate matter (PM2.5) has been associated with premature human mortality. Here we will quantify the global mortality impacts of past and future climate change, considering the effects of climate change on air quality isolated from emission changes. The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) has simulated the past and future surface concentrations of ozone and PM2.5 from each of several GCMs, for emissions from 1850 ("preindustrial") to 2000 ("present-day"), and for the IPCC AR5 Representative Concentration Pathways (RCPs) scenarios to 2100. We will use ozone and PM2.5 concentrations from simulations from five or more global models of atmospheric dynamics and chemistry, for a base year (present-day), pre-industrial conditions, and future scenarios, considering changes in climate and emissions. We will assess the mortality impacts of past climate change by using one simulation ensemble with present emissions and climate and one with present emissions but 1850 climate. We will similarly quantify the potential impacts of future climate change under the four RCP scenarios in 2030, 2050 and 2100. All model outputs will be regridded to the same resolution to estimate multi-model medians and range in each grid cell. Resulting premature deaths will be calculated using these medians along with epidemiologically-derived concentration-response functions, and present-day or future projections of population and baseline mortality rates, considering aging and transitioning disease rates over time. The spatial distributions of current and future global premature mortalities due to ozone and PM2.5 outdoor air pollution will be presented separately

  18. Surgical area contamination--comparable bacterial counts using disposable head and mask and helmet aspirator system, but dramatic increase upon omission of head-gear: an experimental study in horizontal laminar air-flow.

    Science.gov (United States)

    Friberg, B; Friberg, S; Ostensson, R; Burman, L G

    2001-02-01

    The effect of different head coverings on air-borne transmission of bacteria and particles in the surgical area was studied during 30 strictly standardized sham operations performed in a horizontal laminar air flow (LAF) unit. The operating team members wore disposable gowns plus either a non-sterile head covering consisting of a squire type disposable hood and triple laminar face mask, a sterilized helmet aspirator system or no head cover at all. In the wound area both types of head cover resulted in low and comparable air (means of 8 and 4cfu/m(3)) and surface contamination (means of 69 and 126cfu/m(2)/h) rates. Omission of head-gear resulted in a three- to five-fold increase (P > or = 0.01- 0.001), depending on site sampled air contamination rate (mean of 22cfu/m(3)) whereas the bacterial sedimentation rate in the wound area increased about 60-fold ( P > or = 0.0001). A proper head cover minimized the emission of apparently heavy particles that were not removed by the horizontal LAF and contained mainly streptococci, presumably of respiratory tract origin. Dust particle counts revealed no differences between the three experimental situations. No correlation between air and surface contamination rates or between air contamination and air particle counts was found. We conclude that, from a bacteriological point of view, disposable hoods of squire type and face masks are equally as efficient as a helmet aspirator system and both will efficiently contain the substantial emission of bacteria-carrying droplets from the respiratory tract occurring when head cover is omitted. Finally, the use of bacterial air counts to assess surgical site surface contamination in horizontal LAF units must be seriously questioned.

  19. SU-F-BRB-14: Dosimetric Effects at Air- Tissue Boundary Due to Magnetic Field in MR-Guided IMRT/VMAT Delivery for Head and Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Prior, P; Chen, X; Schultz, C; Li, X [Medical College of Wisconsin, Milwaukee, WI (United States)

    2015-06-15

    Purpose: The advent of the MR-Linac enables real-time and high soft tissue contrast image guidance in radiation therapy (RT) delivery. Potential hot-spots at air-tissue interfaces, such as the sphenoid sinus, in RT for head and neck cancer (HNC), could potentially occur due to the electron return effect (ERE). In this study, we investigate the dosimetric effects of ERE on the dose distribution at air-tissues interfaces in HNC IMRT treatment planning. Methods: IMRT plans were generated based on planning CT’s acquired for HNC cases (nasopharynx, base of skull and paranasal sinus) using a research planning system (Monaco, v5.09.06, Elekta) employing Monte Carlo dose calculations with or without the presence of a transverse magnetic field (TMF). The dose in the air cavity was calculated in a 1 & 2 mm thick tissue layer, while the dose to the skin was calculated in a 1, 3 and 5 mm thick tissue layer. The maximum dose received in 1 cc volume, D1cc, were collected at different TMF strengths. Plan qualities generated with or without TMF or with increasing TMF were compared in terms of commonly-used dose-volume parameters (DVPs). Results: Variations in DVPs between plans with and without a TMF present were found to be within 5% of the planning CT. The presence of a TMF results in <5% changes in sinus air tissue interface. The largest skin dose differences with and without TMF were found within 1 mm of the skin surface Conclusion: The presence of a TMF results in practically insignificant changes in HNC IMRT plan quality, except for skin dose. Planning optimization with skin DV constraints could reduce the skin doses. This research was partially supported by Elekta Inc. (Crowley, U.K.)

  20. Algorithm and simulation development in support of response strategies for contamination events in air and water systems.

    Energy Technology Data Exchange (ETDEWEB)

    Waanders, Bart Van Bloemen

    2006-01-01

    Chemical/Biological/Radiological (CBR) contamination events pose a considerable threat to our nation's infrastructure, especially in large internal facilities, external flows, and water distribution systems. Because physical security can only be enforced to a limited degree, deployment of early warning systems is being considered. However to achieve reliable and efficient functionality, several complex questions must be answered: (1) where should sensors be placed, (2) how can sparse sensor information be efficiently used to determine the location of the original intrusion, (3) what are the model and data uncertainties, (4) how should these uncertainties be handled, and (5) how can our algorithms and forward simulations be sufficiently improved to achieve real time performance? This report presents the results of a three year algorithmic and application development to support the identification, mitigation, and risk assessment of CBR contamination events. The main thrust of this investigation was to develop (1) computationally efficient algorithms for strategically placing sensors, (2) identification process of contamination events by using sparse observations, (3) characterization of uncertainty through developing accurate demands forecasts and through investigating uncertain simulation model parameters, (4) risk assessment capabilities, and (5) reduced order modeling methods. The development effort was focused on water distribution systems, large internal facilities, and outdoor areas.

  1. Comparison of arterial and venous blood gases and the effects of analysis delay and air contamination on arterial samples in patients with chronic obstructive pulmonary disease and healthy controls.

    LENUS (Irish Health Repository)

    O'Connor, T M

    2012-01-31

    BACKGROUND: Arterial blood gases (ABGs) are often sampled incorrectly, leading to a \\'mixed\\' or venous sample. Delays in analysis and air contamination are common. OBJECTIVES: We measured the effects of these errors in patients with chronic obstructive pulmonary disease (COPD) exacerbations and controls. METHODS: Arterial and venous samples were analyzed from 30 patients with COPD exacerbation and 30 controls. Venous samples were analysed immediately and arterial samples separated into non-air-contaminated and air-contaminated specimens and analysed at 0, 30, 60, 90 and 180 min. RESULTS: Mean venous pH was 7.371 and arterial pH was 7.407 (p < 0.0001). There was a correlation between venous and arterial pH (r = 0.5347, p < 0.0001). The regression equation to predict arterial pH was: arterial pH = 4.2289 + 0.43113 . venous pH. There were no clinically significant differences in arterial PO associated with analysis delay. A statistically significant decline in pH was detected at 30 min in patients with COPD exacerbation (p = 0.0042) and 90 min in controls (p < 0.0001). A clinically significant decline in pH emerged at 73 min in patients with COPD exacerbation and 87 min in controls. Air contamination was associated with a clinically significant increase in PO in all samples, including those that were immediately analyzed. CONCLUSIONS: Arterial and venous pH differ significantly. Venous pH cannot accurately replace arterial pH. Temporal delays in ABG analysis result in a significant decline in measured pH. ABGs should be analysed within 30 min. Air contamination leads to an immediate increase in measured PO, indicating that air-contaminated ABGs should be discarded.

  2. Water quality deterioration at a karst spring (Gallusquelle, Germany) due to combined sewer overflow: evidence of bacterial and micro-pollutant contamination

    Science.gov (United States)

    Heinz, B.; Birk, S.; Liedl, R.; Geyer, T.; Straub, K. L.; Andresen, J.; Bester, K.; Kappler, A.

    2009-04-01

    The concurrent use of karst aquifers as drinking water resources and receptors of combined sewer overflow lacking appropriate pre-treatment may cause conflicts between drinking water supply and storm water management. A storm water tank (SWT) for combined wastewater is identified as the source of sporadic contamination of a karst spring (Gallusquelle, “Schwäbische Alb”, SW Germany) used for public water supply. Spring water quality was examined by routine and event sampling and by evaluating physicochemical and microbiological parameters. The total number of microbial colonies growing at 20°C and the number of Escherichia coli colonies rose to values up to four orders of magnitude higher than background, 2-5 days after overflow of the SWT. High concentrations of chloride, sodium, and total organic carbon (TOC) and high values of turbidity coincide with this increase. However, high bacterial contamination is also observed while turbidity and TOC are low. Several wastewater-related organic micro-pollutants such as chlorinated and non-chlorinated organophosphates were detected in the SWT and, depending on their K ow values and their biodegradability, in lower concentrations at the spring.

  3. Air distribution and ventilation effectiveness in an occupied room heated by warm air

    DEFF Research Database (Denmark)

    Krajcik, Michal; Simone, Angela; Olesen, Bjarne W.

    2012-01-01

    and at different simulated outside conditions, internal heat gains and air change rates. Floor heating was also simulated and compared with the warm air heating system. Vertical air temperature profiles, air velocity profiles and equivalent temperatures were derived in order to describe the thermal environment......Air distribution, ventilation effectiveness and thermal environment were experimentally studied in a simulated room in a low-energy building heated and ventilated by warm air supplied by a mixing ventilation system. Measurements were performed for various positions of the air terminal devices....... Contaminant removal effectiveness and air change efficiency were used to evaluate ventilation effectiveness. No significant risk of thermal discomfort due to vertical air temperature differences or draught was found. When the room was heated by warm air, buoyancy forces were important for ventilation...

  4. Growth under elevated air temperature alters secondary metabolites in Robinia pseudoacacia L. seedlings in Cd- and Pb-contaminated soils.

    Science.gov (United States)

    Zhao, Y H; Jia, X; Wang, W K; Liu, T; Huang, S P; Yang, M Y

    2016-09-15

    Plant secondary metabolites play a pivotal role in growth regulation, antioxidant activity, pigment development, and other processes. As the global climate changes, increasing atmospheric temperatures and contamination of soil by heavy metals co-occur in natural ecosystems, which alters the pH of rhizosphere soil and influences the bioavailability and mobility of metals. Elevated temperatures in combination with heavy metals are expected to affect plant secondary metabolites, but this issue has not been extensively examined. Here, we investigated secondary metabolites in Robiniapseudoacacia seedlings exposed to elevated temperatures using a passive warming device in combination with Cd- and Pb-contaminated soils. Heavy metals significantly stimulated the accumulation of saponins, phenolic compounds, and flavonoids in leaves and stems; alkaloid compounds increased in leaves and decreased in stems, and condensed tannins fluctuated. Elevated temperatures, alone and in combination with Cd and Pb, caused increases in secondary metabolites in the plant tissues. Phenolic compounds showed the greatest changes among the secondary metabolites and significant interactive effects of temperature and metals were observed. These results suggest that slightly elevated temperature could enhance protective and defense mechanisms of Robinia pseudoacacia seedlings exposed to heavy metals by stimulating the production of secondary metabolites.

  5. ß-Phenylethylamine as a novel nutrient treatment to reduce bacterial contamination due to Escherichia coli O157:H7 on beef meat.

    Science.gov (United States)

    Lynnes, Ty; Horne, S M; Prüß, B M

    2014-01-01

    Bacterial infection by Escherichia coli O157:H7 through the consumption of beef meat or meat products is an ongoing problem, in part because bacteria develop resistances towards chemicals aimed at killing them. In an approach that uses bacterial nutrients to manipulate bacteria into behaviors or cellular phenotypes less harmful to humans, we screened a library of 95 carbon and 95 nitrogen sources for their effect on E. coli growth, cell division, and biofilm formation. In the initial screening experiment using the Phenotype MicroArray(TM) technology from BioLog (Hayward, CA), we narrowed the 190 starting nutrients down to eight which were consecutively tested as supplements in liquid beef broth medium. Acetoacetic acid (AAA) and ß-phenylethylamine (PEA) performed best in this experiment. On beef meat pieces, PEA reduced the bacterial cell count by 90% after incubation of the PEA treated and E. coli contaminated meat pieces at 10°C for one week.

  6. Application of post-discharge region of atmospheric pressure argon and air plasma jet in the contamination control of Candida albicans biofilms

    Directory of Open Access Journals (Sweden)

    Anelise Cristina Osório Cesar Doria

    Full Text Available Introduction:Candida species are responsible for about 80% of hospital fungal infections. Non-thermal plasmas operated at atmospheric pressure are increasingly used as an alternative to existing antimicrobial strategy. This work investigates the action of post-discharge region of a non-thermal atmospheric plasma jet, generated by a gliding arc reactor, on biofilms of standard strain of Candida albicans grown on polyurethane substrate. Methods Samples were divided into three groups: (i non-treated; (ii treated with argon plasma, and (iii treated with argon plus air plasma. Subsequently to plasma treatment, counting of colony-forming units (CFU/ml and cell viability tests were performed. In addition, the surface morphology of the samples was evaluated by scanning electron microscopy (SEM and optical profilometry (OP. Results Reduction in CFU/ml of 85% and 88.1% were observed in groups ii and iii, respectively. Cell viability after treatment also showed reduction of 33% in group ii and 8% in group iii, in comparison with group i (100%. The SEM images allow observation of the effect of plasma chemistry on biofilm structure, and OP images showed a reduction of its surface roughness, which suggests a possible loss of biofilm mass. Conclusion The treatment in post-discharge region and the chemistries of plasma jet tested in this work were effective in controlling Candida albicans biofilm contamination. Finally, it was evidenced that argon plus air plasma was the most efficient to reduce cell viability.

  7. Remediation of Chlorinated Solvent Plumes Using In-Situ Air Sparging—A 2-D Laboratory Study

    Directory of Open Access Journals (Sweden)

    Jeffrey A. Adams

    2011-06-01

    Full Text Available In-situ air sparging has evolved as an innovative technique for soil and groundwater remediation impacted with volatile organic compounds (VOCs, including chlorinated solvents. These may exist as non-aqueous phase liquid (NAPL or dissolved in groundwater. This study assessed: (1 how air injection rate affects the mass removal of dissolved phase contamination, (2 the effect of induced groundwater flow on mass removal and air distribution during air injection, and (3 the effect of initial contaminant concentration on mass removal. Dissolved-phase chlorinated solvents can be effectively removed through the use of air sparging; however, rapid initial rates of contaminant removal are followed by a protracted period of lower removal rates, or a tailing effect. As the air flow rate increases, the rate of contaminant removal also increases, especially during the initial stages of air injection. Increased air injection rates will increase the density of air channel formation, resulting in a larger interfacial mass transfer area through which the dissolved contaminant can partition into the vapor phase. In cases of groundwater flow, increased rates of air injection lessened observed downward contaminant migration effect. The air channel network and increased air saturation reduced relative hydraulic conductivity, resulting in reduced groundwater flow and subsequent downgradient contaminant migration. Finally, when a higher initial TCE concentration was present, a slightly higher mass removal rate was observed due to higher volatilization-induced concentration gradients and subsequent diffusive flux. Once concentrations are reduced, a similar tailing effect occurs.

  8. Heavy metal contamination in bore water due to industrial pollution and polluted and non polluted sea water intrusion in Thoothukudi and Tirunelveli of South Tamil Nadu, India.

    Science.gov (United States)

    Puthiyasekar, C; Neelakantan, M A; Poongothai, S

    2010-12-01

    This study investigates the pollution vulnerability of bore water in the coastal region of Tirunelveli and Thoothukudi in the state of Tamilnadu, India. There are no industries in the Tirunelveli Coastal area whereas there are many industries in SIPCOT (State Industries Promotion Corporation of Tamilnadu) Thoothukudi, and coastal area of Thoothukudi. Bore water from the SIPCOT, coastal area of Thoothukudi and Tirunelveli were collected periodically from July 2006 to May 2008 for this study. These samples were tested and analyzed to find the concentrations of sodium, magnesium, aluminium, potassium, calcium, copper, cadmium, mercury and lead. The toxic cadmium concentration was found in the range of 0.00-0.22 mg Kg⁻¹ at SIPCOT 2 in November 2007, mercury 0.00-0.024 mg Kg⁻¹ and lead 0.00-0.02 mg Kg⁻¹ in SIPCOT 2 in January 2008. The level of contamination is higher than the WHO limits of drinking water standards; but copper and aluminium content are within the limit. On the other hand, the samples taken from bores in Tirunelveli coastal area are non-polluted, and the analysis shows that all the metals are within the limits of WHO standard.

  9. Ability of humans to smell geosmin, 2-MIB and nonadienal in indoor air when using contaminated drinking water.

    Science.gov (United States)

    Omür-Ozbek, P; Little, J C; Dietrich, A M

    2007-01-01

    The most common compounds responsible for off flavours are geosmin, 2-MIB, and nonadienal which are poorly removed by conventional water treatment operations and hence result in customer complaints. Because these odourants are moderately volatile and have very low odour threshold values, it is necessary to determine their concentrations in air when water is used indoors. If the detectable aqueous concentrations for these odourants are known, the utilities may take action to treat their water at times when the concentration of the raw water exceeds the threshold concentration. To predict the concentration in the shower stall and bathroom air after showering, recently published Henry's law constants for the selected odourants and a model developed to determine the volatilization of the odourous compounds by applying two-resistance theory were used. Then the results were compared with the odour threshold concentration data to determine under which conditions the odourants become detectable. For parameters representing a typical bathroom and shower stall setting, the results showed that the odourants become detectable when the aqueous concentration of geosmin and nonadienal exceed 10 ng/L at 42 degrees C. As the aqueous concentration increases, geosmin and nonadienal become detectable at lower temperatures, however 2-MIB is only detectable above 20 ng/L and at 42 degrees C.

  10. Persistent organic contaminants in Saharan dust air masses in West Africa, Cape Verde and the eastern Caribbean.

    Science.gov (United States)

    Garrison, V H; Majewski, M S; Foreman, W T; Genualdi, S A; Mohammed, A; Massey Simonich, S L

    2014-01-15

    Anthropogenic semivolatile organic compounds (SOCs) that persist in the environment, bioaccumulate, are toxic at low concentrations, and undergo long-range atmospheric transport (LRT) were identified and quantified in the atmosphere of a Saharan dust source region (Mali) and during Saharan dust incursions at downwind sites in the eastern Caribbean (U.S. Virgin Islands, Trinidad and Tobago) and Cape Verde. More organochlorine and organophosphate pesticides (OCPPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyl (PCB) congeners were detected in the Saharan dust region than at downwind sites. Seven of the 13 OCPPs detected occurred at all sites: chlordanes, chlorpyrifos, dacthal, dieldrin, endosulfans, hexachlorobenzene (HCB), and trifluralin. Total SOCs ranged from 1.9-126 ng/m(3) (mean = 25 ± 34) at source and 0.05-0.71 ng/m(3) (mean = 0.24 ± 0.18) at downwind sites during dust conditions. Most SOC concentrations were 1-3 orders of magnitude higher in source than downwind sites. A Saharan source was confirmed for sampled air masses at downwind sites based on dust particle elemental composition and rare earth ratios, atmospheric back trajectory models, and field observations. SOC concentrations were considerably below existing occupational and/or regulatory limits; however, few regulatory limits exist for these persistent organic compounds. Long-term effects of chronic exposure to low concentrations of SOCs are unknown, as are possible additive or synergistic effects of mixtures of SOCs, biologically active trace metals, and mineral dust particles transported together in Saharan dust air masses.

  11. Mercury Contamination: Fate and Risk Minimization Strategies

    Science.gov (United States)

    Charlet, L.

    Two river basins have been studied in French Guyana, which are subject to heavy mercury contamination, due to illegal gold mining. Within the framework of an interdisciplinary European project, the fate of mercury in water, air, soil, sediment has been studied, as well as its bio-accumulation in the food chain. This bioaccumulation results in the contamination of amerindian populations, through fish consumption. This study has been done in close contact with the economic and political actors. The results of the scientific interdisciplinary study has been translated in terms of risk minimization strategies, which are analyzed in the framework of the European Water Framework Directive.

  12. Contaminación fecal canina en plazas y veredas de Buenos Aires, 1991-2006 Dog fouling and helminth contamination in parks and sidewalks of Buenos Aires City, 1991-2006

    Directory of Open Access Journals (Sweden)

    Diana Rubel

    2010-08-01

    Full Text Available El objetivo del trabajo fue presentar y analizar los datos de contaminación fecal canina y parasitaria en plazas y veredas de Buenos Aires obtenidos entre 1991 y 2006 por la Cátedra Parasitología General (Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Se censaron las heces en varias plazas cada año en un único día entre 1991-2006. A partir del año 2000 se censaron heces en veredas circundantes. En cada plaza se seleccionaron al azar 30 heces frescas que se conservaron en formol 5% para su análisis parasitológico por el método de flotación de Willis con solución saturada de ClNa. Los 51 censos presentaron una mediana de heces de 288; un 82% de las heces se observaron en los canteros de tierra o pasto. La contaminación fecal en las plazas fue mayor en el período 2000-06 que en el anterior (p = 0.0000. La contaminación fecal de las plazas aumentó con la densidad humana en las manzanas lindantes (p = 0.0076. Las veredas mostraron un patrón inverso, ya que la contaminación fecal fue mayor en las áreas menos densamente pobladas (p = 0.0000. Se detectaron parásitos en un número variable de las heces colectadas en todas las plazas. Los géneros más frecuentes fueron Ancylostoma (20.47%, Trichuris (2.59% y Toxocara (1.70%. Nuestros resultados indican un aumento en la contaminación fecal de las plazas, posiblemente asociado con el aumento del número de perros en la ciudad combinado con las deficiencias en la implementación y el seguimiento de las medidas de control.The aim of this study was to provide data on canine fecal and helminthic contamination from parks and sidewalks in Buenos Aires City, collected by the Laboratory of General Parasitology, School of Sciences, University of Buenos Aires. A census of dog feces was performed in 1-11 parks per year between 1991 and 2006, a single day each year. In the period 2000-2006, the census included feces on sidewalks surrounding the park. Thirty fresh fecal

  13. Novel method for determining DDT in vapour and particulate phases within contaminated indoor air in a malaria area of South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Naude, Yvette, E-mail: yvette.naude@up.ac.za [Department of Chemistry, University of Pretoria, Private Bag X20, Hatfield 0028, Pretoria (South Africa); Rohwer, Egmont R., E-mail: egmont.rohwer@up.ac.za [Department of Chemistry, University of Pretoria, Private Bag X20, Hatfield 0028, Pretoria (South Africa)

    2012-06-12

    Highlights: Black-Right-Pointing-Pointer We present a novel denuder for the determination of DDT in contaminated indoor air. Black-Right-Pointing-Pointer Single step concentration of vapour phase on PDMS, particulate phase on filter. Black-Right-Pointing-Pointer Solvent-free green technique, sample extraction not required. Black-Right-Pointing-Pointer Ratios of airborne p,p Prime -DDD/p,p Prime -DDT and of o,p Prime -DDT/p,p Prime -DDT are unusual. Black-Right-Pointing-Pointer Insecticidal efficacy of technical DDT may be compromised. - Abstract: The organochlorine insecticide DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) is still used for malaria vector control in certain areas of South Africa. The strict Stockholm Convention on Persistent Organic Pollutants (POPs) allows spraying on the inside of traditional dwellings with DDT. In rural villages contaminated dust presents an additional pathway for exposure to DDT. We present a new method for the determination of DDT in indoor air where separate vapour and particulate samples are collected in a single step with a denuder configuration of a multi-channel open tubular silicone rubber (polydimethylsiloxane (PDMS)) trap combined with a micro quartz fibre filter. The multi-channel PDMS trap section of the denuder concentrates vapour phase insecticide whereas particle associated insecticide is transferred downstream where it is collected on a micro-fibre filter followed by a second multi-channel PDMS trap to capture the blow-off from the filter. The multi-channel PDMS trap and filter combination are designed to fit a commercial thermal desorber for direct introduction of samples into a GC-MS. The technique is solvent-free. Analyte extraction and sample clean-up is not required. Two fractions, vapour phase and particulate phase p,p Prime -DDT, o,p Prime -DDT; p,p Prime -DDD, o,p Prime -DDD; p,p Prime -DDE and o,p Prime -DDE in 4 L contaminated indoor air, were each quantitatively analysed by GC-MS using

  14. A numerical method to determine the steady state distribution of passive contaminant in generic ventilation systems.

    Science.gov (United States)

    Li, Xianting; Shao, Xiaoliang; Ma, Xiaojun; Zhang, Yuanhui; Cai, Hao

    2011-08-15

    Ventilation system with air recirculation is designed to conserve energy, yet at the same time may result in transporting hazardous substance among different rooms in the same building, which is a concern in indoor air quality control. There is a lack of effective methods to predict indoor contaminant distribution primarily because of uncertainty of the contaminant concentration in supply air which in turn due to the mixing ratio of fresh and recirculation air. In this paper, a versatile numerical method to determine the pollutant distribution of ventilation system with recirculation at steady state is proposed based on typical ventilation systems with accessibility of supply air (ASA) and accessibility of contaminant source (ACS). The relationship is established between contaminant concentrations of supply air and return air in a ventilated room or zone. The concentrations of supply air and contaminant distribution in each room can be determined using such parameters as ASA and ACS. The proposed method is validated by both experimental data and numerical simulation result. The computing speed of the proposed method is compared with the iteration method. The comparisons between the proposed method and the lumped parameter model are also conducted. The advantages of the proposed method in terms of accuracy, speed and versatility make it advantageous to be applied in air quality control of complex ventilation systems with recirculation.

  15. Microbial survey of the mummies from the Capuchin Catacombs of Palermo, Italy: biodeterioration risk and contamination of the indoor air.

    Science.gov (United States)

    Piñar, Guadalupe; Piombino-Mascali, Dario; Maixner, Frank; Zink, Albert; Sterflinger, Katja

    2013-11-01

    The Capuchin Catacombs of Palermo contain over 1800 preserved bodies dating from the 16th to 20th centuries AD and showing evidence of biodeterioration. An extensive microbiological and molecular investigation was recently performed. Samples were taken from skin, muscle, hair, bone, stuffing materials, clothes, and surrounding walls as well as from the indoor air. In this study, we witnessed that the different degradation phenomena observed on the variety of materials located at the Capuchin Catacombs of Palermo are biological in origin. Molecular techniques showed the dominance of halophilic species of the domains Bacteria and Archaea on the walls and - as a result of salt emanating from the walls - on the mummies themselves. Nevertheless, specialized microorganisms belonging to taxa well-known for their cellulolytic and proteolytic activities were detected on clothes and stuffing material, and on skin, muscle, hair, and bone, respectively. This specialized microbiota is threatening the conservation of the mummies themselves. Additionally, sequences related to the human skin microbiome and to some pathogenic Bacteria (order Clostridiales) and fungi (genus Phialosimplex) were identified on samples derived from the mummies. Furthermore, a phosphate-reducing fungus, Penicillium radicum, was detected on bone. Finally, the high concentration of airborne fungal spores is not conducive to the conservation of the human remains and is posing a potential health risk for visitors.

  16. Spatial response surface modelling in the presence of data paucity for the evaluation of potential human health risk due to the contamination of potable water resources.

    Science.gov (United States)

    Liu, Shen; McGree, James; Hayes, John F; Goonetilleke, Ashantha

    2016-10-01

    Potential human health risk from waterborne diseases arising from unsatisfactory performance of on-site wastewater treatment systems is driven by landscape factors such as topography, soil characteristics, depth to water table, drainage characteristics and the presence of surface water bodies. These factors are present as random variables which are spatially distributed across a region. A methodological framework is presented that can be applied to model and evaluate the influence of various factors on waterborne disease potential. This framework is informed by spatial data and expert knowledge. For prediction at unsampled sites, interpolation methods were used to derive a spatially smoothed surface of disease potential which takes into account the uncertainty due to spatial variation at any pre-determined level of significance. This surface was constructed by accounting for the influence of multiple variables which appear to contribute to disease potential. The framework developed in this work strengthens the understanding of the characteristics of disease potential and provides predictions of this potential across a region. The study outcomes presented constitutes an innovative approach to environmental monitoring and management in the face of data paucity.

  17. Chemical and ecotoxicological analyses of sediments and elutriates of contaminated rivers due to e-waste recycling activities using a diverse battery of bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Wang, F.; Leung, A.O.W.; Wu, S.C.; Yang, M.S. [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong (Hong Kong); Wong, M.H., E-mail: mhwong@hkbu.edu.h [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong (Hong Kong)

    2009-07-15

    A multi-trophic, multi-exposure phase assessment approach was applied to characterize the toxicity of sediments collected from two rivers in Guiyu, China, an e-waste recycling centre. Elutriate toxicity tests (bacterium Vibrio fischeri and microalga Selenastrum capricornutum) and whole sediment toxicity test (crustacean Heterocypris incongruens) showed that most sediments exhibited acute toxicity, due to elevated heavy metals and PAHs levels, and low pH caused by uncontrolled acid discharge. The survival rates of crustaceans were negatively (p < 0.05) correlated with total PAHs in sediments (411-1755 mg kg{sup -1}); EC50s of V. fischeri on the elutriates were significantly correlated with elutriate pH (p < 0.01). Significant (p < 0.05) correlations between the induction of hepatic metallothionein in tilapia (Oreochromis mossambicus) and metal concentrations (Cu, Zn, Pb) in sediments were also observed, when fish were fed with diets containing sediment. The results showed that uncontrolled e-waste recycling activities may bring adverse effects to local aquatic ecosystem. - Toxicity tests using different trophic organisms provided important information, supplementing chemical analyses.

  18. Investigation of the contamination of air and articles in ambulance and the effect of disinfection observation%救护车内空气、物品染菌量调查及干预效果观察

    Institute of Scientific and Technical Information of China (English)

    杨丽萍

    2011-01-01

    Objective: To investigate the bacterial contamination of air and articles in ambulance, and observe the effect of disinfection. Methods: The bacterial contamination of the air and articles in one ambulance were detected before and after disinfection in early,middle and end per month from May. 2009 to Oct. 2009. Results :The pollution situation of air and articles in ambulance was serious before disinfection. The bacterial contamination was decreased significantly after disinfection. And the difference was statistically significant( P < 0.01 ). Conclusions: The pollution situation of air and articles in ambulance is serious. It is necessary to establish a strict disinfection management system.%目的:调查救护车内空气、物品的染菌量情况,观察消毒处理的效果.方法:2009年5~10月的每月上、中、下旬对3辆救护车内空气和物品表面进行消毒前后染菌量监测.结果:消毒前救护车内空气和物品的污染情况严重,消毒后染菌量明显下降(P<0.01).结论:救护车内空气和物品的污染状况严重,需加强其消毒和监测工作.

  19. Bioremediation of contaminated groundwater

    Science.gov (United States)

    Hazen, Terry C.; Fliermans, Carl B.

    1995-01-01

    An apparatus and method for in situ remediation of contaminated subsurface soil or groundwater contaminated by chlorinated hydrocarbons. A nutrient fluid is selected to stimulate the growth and reproduction of indigenous subsurface microorganisms that are capable of degrading the contaminants; an oxygenated fluid is selected to create a generally aerobic environment for these microorganisms to degrade the contaminants, leaving only pockets that are anaerobic. The nutrient fluid is injected periodically while the oxygenated fluid is injected continuously and both are extracted so that both are drawn across the plume. The nutrient fluid stimulates microbial colony growth; withholding it periodicially forces the larger, healthy colony of microbes to degrade the contaminants. Treatment is continued until the subsurface concentration of contaminants is reduced to an acceptable, preselected level. The nutrient fluid can be methane and the oxygenated fluid air for stimulating production of methanotrophs to break down chlorohydrocarbons, especially trichloroethylene (TCE) and tetrachloroethylene.

  20. Assessment of intrinsic bioremediation of gasoline contamination in the shallow aquifer, Laurel Bay Exchange, Marine Corps Air Station Beaufort, South Carolina

    Science.gov (United States)

    Landmeyer, J.E.; Chapelle, Francis; Bradley, P.M.

    1996-01-01

    Laboratory, field, and digital solute-transport- modeling studies demonstrate that microorganisms indigenous to the shallow ground-water system at Laurel Bay Exchange, Marine Corps Air Station Beaufort, South Carolina, can degrade petroleum hydrocarbons in gasoline released at the site. Microorganisms in aquifer sediments incubated in the laboratory under aerobic and anaerobic conditions mineralized radiolabeled carbon 14-toluene to 14C-carbon dioxide with first-order rate constants of Kbio = -0.640 per day and Kbio = -0.003 per day, respectively. Digital solute- transport modeling using the numerical code SUTRA revealed that anaerobic biodegradation of benzene occurs with a first-order rate constant near Kbio = -0.00025 per day. Sandy aquifer material beneath Laurel Bay Exchange is characterized by relatively high hydraulic conductivities (Kaq = 8.9 to 17.3 feet per day), average ground-water flow rate of about 60 feet per year, and a relatively uniform hydraulic gradient of 0.004 feet per foot. The sandy aquifer material also has low adsorptive potentials for toluene and benzene (both about Kad = 2.0 x 10-9 cubic feet per milligram), because of the lack of natural organic matter in the aquifer. The combination of this ground-water-flow rate and absence of significant adsorptive capacity in the aquifer permits toluene and benzene concentrations to be detected downgradient from the source area in monitoring wells, even though biodegradation of these compounds has been demonstrated. Solute-transport simulations, however, indicate that toluene and benzene will not reach the Broad River, the nearest point of contact with wildlife or human populations, about 3,600 feet west of the site boundary. These simulations also show that contamination will not be transported to the nearest Marine Corps property line about 2,400 feet south of the site. This is primarily because the source of contaminants has essentially been removed, and the low adsorptive capacity of the aquifer

  1. Air exposure behavior of the semiterrestrial crab Neohelice granulata allows tolerance to severe hypoxia but not prevent oxidative damage due to hypoxia-reoxygenation cycle.

    Science.gov (United States)

    de Lima, Tábata Martins; Geihs, Márcio Alberto; Nery, Luiz Eduardo Maia; Maciel, Fábio Everton

    2015-11-01

    The air exposure behavior of the semi-terrestrial crab Neohelice granulata during severe hypoxia was studied. This study also verified whether this behavior mitigates possible oxidative damage, namely lipoperoxidation, caused by hypoxia and reoxygenation cycles. The lethal time for 50% of the crabs subjected to severe hypoxia (0.5 mgO2 · L(-1)) with free access to air was compared to that of crabs subjected to severe hypoxia without access to air. Crabs were placed in aquaria divided into three zones: water (when the animal was fully submersed), land (when the animal was completely emerged) and intermediate (when the animal was in contact with both environments) zones. Then the crabs were held in this condition for 270 min, and the time spent in each zone was recorded. Lipid peroxidation (LPO) damage to the walking leg muscles was determined for the following four experimental conditions: a--normoxic water with free access to air; b--hypoxic water without access to air; c--hypoxic water followed by normoxic water without air access; and d--hypoxic water with free access to air. When exposed to hypoxic water, N. granulata spent significantly more time on land, 135.3 ± 17.7 min, whereas control animals (exposed to normoxic water) spent more time submerged, 187.4 ± 20.2 min. By this behavior, N. granulata was able to maintain a 100% survival rate when exposed to severe hypoxia. However, N. granulata must still return to water after periods of air exposure (~ 14 min), causing a sequence of hypoxia/reoxygenation events. Despite increasing the survival rate, hypoxia with air access does not decrease the lipid peroxidation damage caused by the hypoxia and reoxygenation cycle experienced by these crabs.

  2. Assessment on contamination level due to unintentional produced PCBs in China based on TOPSIS model%基于TOPSIS模型的中国各省区非故意生产多氯联苯污染评价

    Institute of Scientific and Technical Information of China (English)

    崔嵩; 郭亮; 李一凡

    2013-01-01

    随着国民经济的快速发展,工业生产总值的不断增长,非故意生产多氯联苯可能是导致其大气中浓度持续升高的主要来源.基于此,本研究确定我国非故意生产多氯联苯的主要排放源为水泥行业、钢铁烧结、电炉炼钢、初级铜冶炼、初级铅冶炼、初级锌冶炼及热电站(煤),并根据不同排放源的排放因子运用不同的计算方法确定评价指标的权重,然后应用TOPSIS模型对我国各省区非故意生产多氯联苯的排放污染状况进行综合评价.研究结果表明,应用基于排放因子的排放量法确定评价指标权重的TOPSIS法能够客观准确的对污染状况进行评价.经相关性分析得出,我国各省区非故意生产多氯联苯综合污染状况与GDP显著相关,R=0.831,P<0.000 1.运用TOTSIS模型的评价结果有效可行,可为编制非故意生产多氯联苯排放清单地区分配的合理化提供可靠依据,并可对持久性有机污染物的大气污染控制政策及措施的制定提供参考依据.%With rapidly development of economy and industries, the unintentional produced PCBs ( UP-PCBs) become the main source of air pollution. It is investigated the emission sources of UP-PCBs from main emission sources, including thermal power stations, cement kilns, sinter plants in the iron and steel industries, primary copper , lead and zinc smelting. According to emission factors of different emission sources the weights of different evaluation index that was adopted by different methods were calculated, and the TOPSIS model was used to assess the contamination conditions of UP-PCBs in different provinces in China, and significant correlation was found between contamination discharge and GDP, R =0. 831 ,P <0. 000 1. The results showed that the method of emission amount based on emission factors can effectively assess the comprehensive contamination conditions. The assessment results obtained by application of the TOPSIS model

  3. Modeling for Airborne Contamination

    Energy Technology Data Exchange (ETDEWEB)

    F.R. Faillace; Y. Yuan

    2000-08-31

    The objective of Modeling for Airborne Contamination (referred to from now on as ''this report'') is to provide a documented methodology, along with supporting information, for estimating the release, transport, and assessment of dose to workers from airborne radioactive contaminants within the Monitored Geologic Repository (MGR) subsurface during the pre-closure period. Specifically, this report provides engineers and scientists with methodologies for estimating how concentrations of contaminants might be distributed in the air and on the drift surfaces if released from waste packages inside the repository. This report also provides dose conversion factors for inhalation, air submersion, and ground exposure pathways used to derive doses to potentially exposed subsurface workers. The scope of this report is limited to radiological contaminants (particulate, volatile and gaseous) resulting from waste package leaks (if any) and surface contamination and their transport processes. Neutron activation of air, dust in the air and the rock walls of the drift during the preclosure time is not considered within the scope of this report. Any neutrons causing such activation are not themselves considered to be ''contaminants'' released from the waste package. This report: (1) Documents mathematical models and model parameters for evaluating airborne contaminant transport within the MGR subsurface; and (2) Provides tables of dose conversion factors for inhalation, air submersion, and ground exposure pathways for important radionuclides. The dose conversion factors for air submersion and ground exposure pathways are further limited to drift diameters of 7.62 m and 5.5 m, corresponding to the main and emplacement drifts, respectively. If the final repository design significantly deviates from these drift dimensions, the results in this report may require revision. The dose conversion factors are further derived by using concrete of

  4. Uranium contamination due to nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Martin Sanchez, A.; Vera Tome, F.; Diaz Bejarano, J.; Garcia Aparicio, A. (Univ. de Extremadura, Badajoz (Spain). Dept. de Fisica)

    1992-01-01

    Measurements of uranium isotopes and their daughters in the natural series were performed in the cooling reservoirs and their neighborhood of two nuclear power plants, [alpha] and [gamma] spectrometry of samples were used to measure the natural and artificial radionuclides. The nuclear power plants are in the southwest of Spain and one of them has been in operation since 1982, the other plant is in the construction phase. We compare the results obtained for the two sites. (orig.).

  5. Estimation the Number of Mortality Due to Cardiovascular and Respiratory disease, Attributed to pollutants O3, and NO2 in the Air of Tehran.

    Directory of Open Access Journals (Sweden)

    Sevda Fallah jokandan

    2016-03-01

    Full Text Available Introduction and Purpose: Nowadays, the air quality in many major cities is one of the most important environmental problems that seriously compromises the health of residents and causes a range of acute and chronic health effects. herefore, this study was aimed to quantify and estimate the health effects related to the pollutants NO2 and O3 in metropolis of Tehran in 2014 was done by AirQ model. Methods: Data acquired were collected from the environmental organization and the center of air quality control in Tehran. This data were analyzed by Microsoft Excel software, and the processed data was entered AirQ model. The relative risk, baseline incidence and the attributed proportion was estimated and the overall results in case of mortality and morbidity were presented in tables and graphs Results: The results showed that the average annual concentration of NO2 and O3 in Tehran, was respectively 130 and 64 μg/m3. According to the results with baseline incidence of 543.5 per 100,000, the total cumulative number of mortalities attributed to nitrogen dioxide and ozone, were estimated respectively to be 1593 and 946, that included about 2.66% and 1.58% of total mortalities except traffic accidents in Tehran. Conclusion: Our results showed that the level of air pollution has increased in Tehran, which requires more attention of authorities and policy makers to control the air pollution.

  6. RADIATION-HYGIENIC ESTIMATION OF THE POSSIBLE LEVELS OF FAR EAST SEA FRUITS CONTAMINATION WITH LONG LIVING RADIONICLIDES DUE TO THE ACCIDENT ON ‘FUKUSHIMA-1” NPP

    Directory of Open Access Journals (Sweden)

    V. S. Repin

    2012-01-01

    Full Text Available The information on contamination levels of Pacific ocean sea water and spreading of contaminated water is given for the period of the accident on «Fukushima-1» NPP and after it. Data on fishery areals are represented. The analyses of fish contamination levels is fulfilled .The questions of fish monitoring are discussed.

  7. RADIATION-HYGIENIC ESTIMATION OF THE POSSIBLE LEVELS OF FAR EAST SEA FRUITS CONTAMINATION WITH LONG LIVING RADIONICLIDES DUE TO THE ACCIDENT ON ‘FUKUSHIMA-1” NPP

    OpenAIRE

    V. S. Repin

    2012-01-01

    The information on contamination levels of Pacific ocean sea water and spreading of contaminated water is given for the period of the accident on «Fukushima-1» NPP and after it. Data on fishery areals are represented. The analyses of fish contamination levels is fulfilled .The questions of fish monitoring are discussed.

  8. Measurement of Indoor Air Quality by Means of a Breathing Thermal Manikin

    DEFF Research Database (Denmark)

    Brohus, Henrik

    When a person is located in a contaminant field with significant gradients the contaminant distribution is modified locally due to the entrainment and transport of room air in the human convective boundary layer as well as due to the effect of the person acting as an obstacle to the flow field, e....... The local modification of the concentration distribution may affect the personal exposure significantly and, thus, the indoor air quality actually experienced. In this paper measurements of indoor air quality by means of a Breathing Thermal Manikin (BTM) are presented....

  9. A shift in emission time profiles of fossil fuel combustion due to energy transitions impacts source receptor matrices for air quality

    NARCIS (Netherlands)

    Hendriks, C.; Kuenen, J.; Kranenburg, R.; Scholz, Y.; Schaap, M.

    2015-01-01

    Effective air pollution and short-lived climate forcer mitigation strategies can only be designed when the effect of emission reductions on pollutant concentrations and health and ecosystem impacts are quantified. Within integrated assessment modeling source-receptor relationships (SRRs) based on ch

  10. Neumonía por Legionella pneumophila: Experiencia en un Hospital Universitario de Buenos Aires Neumonia due to Legionella pneumophila. Experience gathered in a University Hospital in Buenos Aires

    Directory of Open Access Journals (Sweden)

    Carlos M. Luna

    2004-04-01

    Full Text Available La enfermedad de los legionarios es una causa de neumonía adquirida en la comunidad (NAC reconocida en todo el mundo. En Latinoamérica su incidencia es desconocida. En este estudio se analizó a 9 pacientes con NAC por Legionella pneumophila atendidos entre 1997 y 2001 en el Hospital de Clínicas José de San Martín de la Universidad de Buenos Aires. Se registraron datos de antecedentes, enfermedad actual, contactos, exposición laboral, examen físico, pruebas de laboratorio y uso previo de antibióticos, y se tomó en cuenta la presencia de criterios de gravedad. Nueve pacientes presentaron diagnóstico de NAC por Legionella, ninguno refirió antecedentes de viajes recientes; cuatro de ellos debieron ser internados en unidades de cuidado intensivo. Siete pacientes tenían antecedentes de tabaquismo, 4 tenían EPOC y un paciente linfoma no-Hodgkin. Nuestra casuística corrobora la baja especificidad de la clínica y estudios complementarios para predecir esta etiología. El aislamiento de Legionella es dificultoso, la seroconversión permite el diagnóstico retrospectivo y requiere plazos prolongados y el antígeno urinario aporta un diagnóstico inmediato. Cuando la legionelosis aparece en casos aislados, como ocurriría en Argentina, si no se piensa en esta etiología no se llegará al diagnóstico. Legionella pneumophila es un patógeno de NAC en nuestro medio, debe buscarse mejor, particularmente en pacientes graves, inmunodeprimidos y en fumadores con enfermedad pulmonar obstructiva crónica (EPOC.Legionnaires’ disease is a well recognized cause of community acquired pneumonia (CAP all around the world. In Latin America its incidence remains unknown. This study analyzed a cohort of 9 patients with CAP due to Legionella pneumophila observed from 1997 to 2001, in the Hospital de Clínicas José de San Martín, University of Buenos Aires. Clinical history included recent illnesses, work exposure, physical exam, prior antibiotic use and

  11. 日本福岛核事故对兰州地区所致放射性污染的监测与分析%Monitoring and Analysis of Radioactive Contamination in Lanzhou Due to Japan Fukushima Nuclear Accident

    Institute of Scientific and Technical Information of China (English)

    邬家龙; 孙卫; 王赟; 王延俊; 罗伟立; 张飙

    2013-01-01

    The purpose of the paper is to survey the level of radioactive contamination due to the Japan Fukushima nuclear accident in Lanzhou.The radionuclide 131I,137 Cs,134 Cs and 136Cs leaked in Fukushima nuclear accident in atmosphere aerosols,drinking water,vegetable and milk in Lanzhou were detected.The radionuclide leaked in the accident didn' t be detected in drinking water,vegetable and milk.The value of the gross α radioactivity and gross β radioactivity of drinking water in Lanzhou was below the limits of national standard.The radioactive contamination due to the Japan Fukushima nuclear accident did not impact on public health in Lanzhou.%论文调查了日本福岛核事故导致的兰州地区放射性污染情况,监测了兰州地区大气气溶胶、自来水、黄河水、蔬菜、牛奶中的核事故泄漏放射性核素,并监测自来水、黄河水的总α放射性、总β放射性.测量了兰州地区大气气溶胶中来自福岛核电站泄漏放射性核素131I、137Cs、134Cs、136Cs,结果在采集的自来水、黄河水、蔬菜、牛奶样品中未检测出核事故泄漏放射性核素,自来水、黄河水样品的总α放射性、总β放射性监测结果均低于国家生活饮用水卫生标准中的限值.由此可知日本福岛核事故导致的兰州地区放射性污染不会对公众健康造成影响.

  12. Long-term (1992-2004) record of lead, cadmium, and zinc air contamination in Warsaw, Poland: Determination by chemical analysis of moss bags and leaves of Crimean linden

    Energy Technology Data Exchange (ETDEWEB)

    Dmuchowski, Wojciech, E-mail: dmuchowski@ob.neostrada.p [Botanical Garden-Center for Conservation of Biological Diversity, Polish Academy of Sciences, 2 Prawdziwka St., 02-973 Warszawa (Poland); Warsaw University of Life Sciences-SGGW, Faculty of Agriculture and Biology, 159 Nowoursynowska St., 02-776 Warszawa (Poland); Bytnerowicz, Andrzej [US Forest Service, Pacific Southwest Research Station, 4955 Canyon Crest Drive, Riverside, CA 92507 (United States)

    2009-12-15

    Between 1992 and 2004, air contamination with lead (Pb), cadmium (Cd), and zinc (Zn) in Warsaw, Poland, was monitored annually with moss (Sphagnum fallax) bags on a network of 230 sites covering the entire city. During the study the highest contamination was near the Warszawa Steel Mill, northwestern Warsaw. Lead concentrations in moss bags decreased in time, while those of Cd and Zn did not show clear trends. Between 1994 and 2004, Pb, Cd, and Zn were also monitored in the Crimean linden (Tilia Euchlora) foliage along the main city avenue and in a northwestern warsaw park. Lead concentrations decreased more near the avenue than in the park, indicating that the phasing-out of leaded gasoline had a major effect on reduced Pb contamination in Warsaw. At the same time, foliar concentrations of Cd and Zn in both areas decreased much less. - Between 1992 and 2004, concentrations of Pb decreased, while those of Cd and Zn remained little changed in moss bags and linden foliage exposed to ambient air in Warsaw, Poland.

  13. Changes in air quality and tropospheric composition due to depletion of stratospheric ozone and interactions with changing climate: implications for human and environmental health.

    Science.gov (United States)

    Madronich, S; Shao, M; Wilson, S R; Solomon, K R; Longstreth, J D; Tang, X Y

    2015-01-01

    UV radiation is an essential driver for the formation of photochemical smog, which includes ground-level ozone and particulate matter (PM). Recent analyses support earlier work showing that poor outdoor air quality is a major environmental hazard as well as quantifying health effects on regional and global scales more accurately. Greater exposure to these pollutants has been linked to increased risks of cardiovascular and respiratory diseases in humans and is associated globally with several million premature deaths per year. Ozone also has adverse effects on yields of crops, leading to loss of billions of US dollars each year. These detrimental effects also may alter biological diversity and affect the function of natural ecosystems. Future air quality will depend mostly on changes in emission of pollutants and their precursors, but changes in UV radiation and climate will contribute as well. Significant reductions in emissions, mainly from the energy and transportation sectors, have already led to improved air quality in many locations. Air quality will continue to improve in those cities/states that can afford controls, and worsen where the regulatory infrastructure is not available. Future changes in UV radiation and climate will alter the rates of formation of ground-level ozone and photochemically-generated particulate matter and must be considered in predictions of air quality. The decrease in UV radiation associated with recovery of stratospheric ozone will, according to recent global atmospheric model simulations, lead to increases in ground-level ozone at most locations. If correct, this will add significantly to future ground-level ozone trends. However, the spatial resolution of these global models is insufficient to inform policy at this time, especially for urban areas. UV radiation affects the atmospheric concentration of hydroxyl radicals, ˙OH, which are responsible for the self-cleaning of the atmosphere. Recent measurements confirm that, on a

  14. External dose-rate conversion factors of radionuclides for air submersion, ground surface contamination and water immersion based on the new ICRP dosimetric setting.

    Science.gov (United States)

    Yoo, Song Jae; Jang, Han-Ki; Lee, Jai-Ki; Noh, Siwan; Cho, Gyuseong

    2013-01-01

    For the assessment of external doses due to contaminated environment, the dose-rate conversion factors (DCFs) prescribed in Federal Guidance Report 12 (FGR 12) and FGR 13 have been widely used. Recently, there were significant changes in dosimetric models and parameters, which include the use of the Reference Male and Female Phantoms and the revised tissue weighting factors, as well as the updated decay data of radionuclides. In this study, the DCFs for effective and equivalent doses were calculated for three exposure settings: skyshine, groundshine and water immersion. Doses to the Reference Phantoms were calculated by Monte Carlo simulations with the MCNPX 2.7.0 radiation transport code for 26 mono-energy photons between 0.01 and 10 MeV. The transport calculations were performed for the source volume within the cut-off distances practically contributing to the dose rates, which were determined by a simplified calculation model. For small tissues for which the reduction of variances are difficult, the equivalent dose ratios to a larger tissue (with lower statistical errors) nearby were employed to make the calculation efficient. Empirical response functions relating photon energies, and the organ equivalent doses or the effective doses were then derived by the use of cubic-spline fitting of the resulting doses for 26 energy points. The DCFs for all radionuclides considered important were evaluated by combining the photon emission data of the radionuclide and the empirical response functions. Finally, contributions of accompanied beta particles to the skin equivalent doses and the effective doses were calculated separately and added to the DCFs. For radionuclides considered in this study, the new DCFs for the three exposure settings were within ±10 % when compared with DCFs in FGR 13.

  15. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Structure of flows due to interaction of CO2 laser pulse pairs with a target in air

    Science.gov (United States)

    Bakeev, A. A.; Nikolashina, L. I.; Potashkin, M. N.; Prokopenko, N. V.

    1991-06-01

    An analysis is made of two pulses from an electric-discharge CO2 laser, of 6-12 μs duration and separated in time, incident on a target surrounded by air of normal density. The main attention is concentrated on breakdown of air by the second pulse at a boundary separating the "cold gas" and the plasma generated by the first pulse ("hot gas"). A gasdynamic system of waves is then generated. It consists of an absorption wave traveling along the cold gas opposite to the laser radiation and a wave propagating along the hot gas toward the target. The best agreement between the theory and experiment is obtained employing a model in which an absorption wave travels along the hot gas in an overcompressed detonation regime. The density of the radiation flux needed to maintain such a wave is 20-30% of the average density of the laser radiation flux carried by the second pulse.

  16. A shift in emission time profiles of fossil fuel combustion due to energy transitions impacts source receptor matrices for air quality.

    Science.gov (United States)

    Hendriks, Carlijn; Kuenen, Jeroen; Kranenburg, Richard; Scholz, Yvonne; Schaap, Martijn

    2015-03-01

    Effective air pollution and short-lived climate forcer mitigation strategies can only be designed when the effect of emission reductions on pollutant concentrations and health and ecosystem impacts are quantified. Within integrated assessment modeling source-receptor relationships (SRRs) based on chemistry transport modeling are used to this end. Currently, these SRRs are made using invariant emission time profiles. The LOTOS-EUROS model equipped with a source attribution module was used to test this assumption for renewable energy scenarios. Renewable energy availability and thereby fossil fuel back up are strongly dependent on meteorological conditions. We have used the spatially and temporally explicit energy model REMix to derive time profiles for backup power generation. These time profiles were used in LOTOS-EUROS to investigate the effect of emission timing on air pollutant concentrations and SRRs. It is found that the effectiveness of emission reduction in the power sector is significantly lower when accounting for the shift in the way emissions are divided over the year and the correlation of emissions with synoptic situations. The source receptor relationships also changed significantly. This effect was found for both primary and secondary pollutants. Our results indicate that emission timing deserves explicit attention when assessing the impacts of system changes on air quality and climate forcing from short lived substances.

  17. Arctic smoke - record high air pollution levels in the European Arctic due to agricultural fires in Eastern Europe in spring 2006

    Science.gov (United States)

    Stohl, A.; Berg, T.; Burkhart, J. F.; Fjæraa, A. M.; Forster, C.; Herber, A.; Hov, Ø.; Lunder, C.; McMillan, W. W.; Oltmans, S.; Shiobara, M.; Simpson, D.; Solberg, S.; Stebel, K.; Ström, J.; Tørseth, K.; Treffeisen, R.; Virkkunen, K.; Yttri, K. E.

    2007-01-01

    In spring 2006, the European Arctic was abnormally warm, setting new historical temperature records. During this warm period, smoke from agricultural fires in Eastern Europe intruded into the European Arctic and caused the most severe air pollution episodes ever recorded there. This paper confirms that biomass burning (BB) was indeed the source of the observed air pollution, studies the transport of the smoke into the Arctic, and presents an overview of the observations taken during the episode. Fire detections from the MODIS instruments aboard the Aqua and Terra satellites were used to estimate the BB emissions. The FLEXPART particle dispersion model was used to show that the smoke was transported to Spitsbergen and Iceland, which was confirmed by MODIS retrievals of the aerosol optical depth (AOD) and AIRS retrievals of carbon monoxide (CO) total columns. Concentrations of halocarbons, carbon dioxide and CO, as well as levoglucosan and potassium, measured at Zeppelin mountain near Ny Ålesund, were used to further corroborate the BB source of the smoke at Spitsbergen. The ozone (O3) and CO concentrations were the highest ever observed at the Zeppelin station, and gaseous elemental mercury was also elevated. A new O3 record was also set at a station on Iceland. The smoke was strongly absorbing - black carbon concentrations were the highest ever recorded at Zeppelin - and strongly perturbed the radiation transmission in the atmosphere: aerosol optical depths were the highest ever measured at Ny Ålesund. We furthermore discuss the aerosol chemical composition, obtained from filter samples, as well as the aerosol size distribution during the smoke event. Photographs show that the snow at a glacier on Spitsbergen became discolored during the episode and, thus, the snow albedo was reduced. Samples of this polluted snow contained strongly elevated levels of potassium, sulphate, nitrate and ammonium ions, thus relating the discoloration to the deposition of the smoke

  18. Arctic smoke – record high air pollution levels in the European Arctic due to agricultural fires in Eastern Europe in spring 2006

    Directory of Open Access Journals (Sweden)

    A. Stohl

    2007-01-01

    Full Text Available In spring 2006, the European Arctic was abnormally warm, setting new historical temperature records. During this warm period, smoke from agricultural fires in Eastern Europe intruded into the European Arctic and caused the most severe air pollution episodes ever recorded there. This paper confirms that biomass burning (BB was indeed the source of the observed air pollution, studies the transport of the smoke into the Arctic, and presents an overview of the observations taken during the episode. Fire detections from the MODIS instruments aboard the Aqua and Terra satellites were used to estimate the BB emissions. The FLEXPART particle dispersion model was used to show that the smoke was transported to Spitsbergen and Iceland, which was confirmed by MODIS retrievals of the aerosol optical depth (AOD and AIRS retrievals of carbon monoxide (CO total columns. Concentrations of halocarbons, carbon dioxide and CO, as well as levoglucosan and potassium, measured at Zeppelin mountain near Ny Ålesund, were used to further corroborate the BB source of the smoke at Spitsbergen. The ozone (O3 and CO concentrations were the highest ever observed at the Zeppelin station, and gaseous elemental mercury was also elevated. A new O3 record was also set at a station on Iceland. The smoke was strongly absorbing – black carbon concentrations were the highest ever recorded at Zeppelin – and strongly perturbed the radiation transmission in the atmosphere: aerosol optical depths were the highest ever measured at Ny Ålesund. We furthermore discuss the aerosol chemical composition, obtained from filter samples, as well as the aerosol size distribution during the smoke event. Photographs show that the snow at a glacier on Spitsbergen became discolored during the episode and, thus, the snow albedo was reduced. Samples of this polluted snow contained strongly elevated levels of potassium, sulphate, nitrate and ammonium ions, thus relating the discoloration to the

  19. Improving IAQ Via Air Filtration.

    Science.gov (United States)

    Monk, Brian

    1999-01-01

    Provides tips on using air filtration to control indoor air quality in educational facilities, including dedicated spaces with unique air quality conditions such as in libraries, museums and archival storage areas, kitchens and dining areas, and laboratories. The control of particulate contaminants, gaseous contaminants, and moisture buildup are…

  20. Basic radiological studies contamination control experiments

    Energy Technology Data Exchange (ETDEWEB)

    Duce, S.W.; Winberg, M.R.; Freeman, A.L.

    1989-09-01

    This report describes the results of experiments relating to contamination control performed in support of the Environmental Restoration Programs Retrieval Project. During the years 1950 to 1970 waste contaminated with plutonium and other transuranic radionuclides was disposed of in shallow land-filled pits and trenches at the Idaho National Engineering Laboratory. Due to potential for migration of radionuclides to an existing aquifer the feasibility of retrieving and repackaging the waste for placement in a final repository is being examined as part of a retrieval project. Contamination control experiments were conducted to determine expected respirable and nonrespirable plutonium contaminated dust fractions and the effectiveness of various dust suppression techniques. Three soil types were tested to determine respirable fractions: Rocky Flats Plant generic soil, Radioactive Waste Management Complex generic soil, and a 1:1 blend of the two soil types. Overall, the average respirable fraction of airborne dust was 5.4% by weight. Three contamination control techniques were studied: soil fixative sprays, misting agents, and dust suppression agents. All of the tested agents proved to be effective in reducing dust in the air. Details of product performance and recommended usage are discussed.

  1. Indoor air quality due to secondhand smoke: Signals from selected hospitality locations in rural and urban areas of Bangalore and Dharwad districts in Karnataka, India

    Directory of Open Access Journals (Sweden)

    Mark J Travers

    2015-01-01

    Full Text Available BACKGROUND: Tobacco smoke has compounds that are known as human carcinogens. With every breath of secondhand smoke we inhale thousands of chemicals. The Government of India in the interest of public health has enacted the Cigarette and Other Tobacco Products Act (COTPA, 2003, which bans smoking in all the public places including hotels and restaurants. The purpose of this study was to observe and record air pollution in smoke free and smoke observed locations and thereby find out whether the owners/managers of hotels, restaurants, and bars comply with rules of COTPA. OBJECTIVES: The objectives of the study were to measure and compare the level of particulate air pollution from secondhand smoke (PM2.5 in smoking and nonsmoking venues. MATERIALS AND METHODS: The study was conducted from September 2009 to March 2010 in Karnataka, India following a nonrandom sample of 79 locations, which included restaurants, bars, cafes, hotels, and tea stalls in two districts. The concentration of PM2.5was measured using a TSI SidePak AM510 Personal Aerosol Monitor. RESULTS: In Karnataka out of the 79 hospitality locations, smoking was observed in 58% places and only 28% had displayed the required “No Smoking” signage. Places where indoor smoking was observed had high levels of air pollution with average 135 PM2.5, which were 3.1 times higher than the average 43 PM2.5in smoke-free locations and 14 times higher than the World Health Organization (WHO target air quality guideline for PM2.5. The average PM2.5levels in different locations ranged from 11 to 417 μg/m3 and was lower in the case of apparently compliant designated smoking area (DSR. CONCLUSIONS: The patrons and the workers in the hospitality sector continue to be exposed to secondhand smoke despite the enactment of COTPA, which bans smoking in public places. This situation demands stringent measures for effective implementation of the Smoke Free Act and negative response to smoking among civil society.

  2. Fuel cell cathode air filters: Methodologies for design and optimization

    Science.gov (United States)

    Kennedy, Daniel M.; Cahela, Donald R.; Zhu, Wenhua H.; Westrom, Kenneth C.; Nelms, R. Mark; Tatarchuk, Bruce J.

    Proton exchange membrane (PEM) fuel cells experience performance degradation, such as reduction in efficiency and life, as a result of poisoning of platinum catalysts by airborne contaminants. Research on these contaminant effects suggests that the best possible solution to allowing fuel cells to operate in contaminated environments is by filtration of the harmful contaminants from the cathode air. A cathode air filter design methodology was created that connects properties of cathode air stream, filter design options, and filter footprint, to a set of adsorptive filter parameters that must be optimized to efficiently operate the fuel cell. Filter optimization requires a study of the trade off between two causal factors of power loss: first, a reduction in power production due to poisoning of the platinum catalyst by chemical contaminants and second, an increase in power requirements to operate the air compressor with a larger pressure drop from additional contaminant filtration. The design methodology was successfully applied to a 1.2 kW fuel cell using a programmable algorithm and predictions were made about the relationships between inlet concentration, breakthrough time, filter design, pressure drop, and compressor power requirements.

  3. Use of doubly stochastic poisson processes in estimating health effects due to air pollution. [Effects of air pollution on incidence of acute respiratory diseases in New York City area

    Energy Technology Data Exchange (ETDEWEB)

    Cuzick, J.M.

    1976-01-01

    Some questions associated with statistical inference of doubly stochastic Poisson processes are discussed. This general model appears to be of value in studying a number of problems in environmental health in which the factors which affect the rate at which certain diseases occur cannot be deterministically characterized. The model's applicability to a study of air pollution and incidence of acute respiratory diseases in the New York City area is examined.

  4. THE AVERAGE ANNUAL EFFECTIVE DOSES FOR THE POPULATION IN THE SETTLEMENTS OF THE RUSSIAN FEDERATION ATTRIBUTED TO ZONES OF RADIOACTIVE CONTAMINATION DUE TO THE CHERNOBYL ACCIDENT (FOR ZONATION PURPOSES, 2014

    Directory of Open Access Journals (Sweden)

    G. Ja. Bruk

    2015-01-01

    Full Text Available The Chernobyl accident in 1986 is one of the most large-scale radiation accidents in the world. It led to radioactive contamination of large areas in the European part of the Russian Federation and at the neighboring countries. Now, there are more than 4000 settlements with the total population of 1.5 million in the radioactively contaminated areas of the Russian Federation. The Bryansk region is the most intensely contaminated region. For example, the Krasnogorskiy district still has settlements with the level of soil contamination by cesium-137 exceeding 40 Cu/km2. The regions of Tula, Kaluga and Orel are also significantly affected. In addition to these four regions, there are 10 more regions with the radioactively contaminated settlements. After the Chernobyl accident, the affected areas were divided into zones of radioactive contamination. The attribution of the settlements to a particular zone is determined by the level of soil contamination with 137Cs and by a value of the average annual effective dose that could be formed in the absence of: 1 active measures for radiation protection, and 2 self-limitation in consumption of the local food products. The main regulatory document on this issue is the Federal law № 1244-1 (dated May, 15,1991 «On the social protection of the citizens who have been exposed to radiation as a result of the accident at the Chernobyl nuclear power plant». The law extends to the territories, where, since 1991: – The average annual effective dose for the population exceeds 1 mSv (the value of effective dose that could be formed in the absence of active radiation protection measures and self-limitation in consumption of the local food products; – Soil surface contamination with cesium-137 exceeds 1 Cu/km2. The paper presents results of calculations of the average effective doses in 2014. The purpose was to use the dose values (SGED90 in zonation of contaminated territories. Therefore, the

  5. Percepción de riesgo a la salud por contaminación del aire en adolescentes de la Ciudad de México Perception of health risks due to air pollution in adolescents in Mexico City

    Directory of Open Access Journals (Sweden)

    Minerva Catalán-Vázquez

    2009-04-01

    Full Text Available OBJETIVO: Analizar las relaciones que se establecen entre contaminación del aire y salud-enfermedad-muerte en una muestra de estudiantes de la Ciudad de México. MATERIAL Y MÉTODOS: Se realizó una encuesta a 1 274 alumnos de secundaria de 14 escuelas en cinco zonas del Distrito Federal, entre marzo y abril de 2003. Muestreo polietápico de áreas geoestadísticas básicas (AGEB. RESULTADOS: El 84.4% considera alta o muy alta la contaminación del aire en la Ciudad de México, que disminuye al aproximarse al espacio más inmediato del alumno. Los riesgos a la salud van desde efectos en la salud respiratoria, 66.9%, a otras consecuencias en la vida diaria, 2.2%. Los predictores de percibir la contaminación como grave/muy grave son: a que la asocien con la posibilidad de causar la muerte (RM= 1.35, IC 95%= 1.02-1.77, y b asistencia a escuelas en la zona de La Merced (RM= 2.23, IC 95%= 1.56-3.21. CONCLUSIONES: Los determinantes de la percepción para esta población de adolescentes son: género, zona de ubicación de la escuela y las diferencias en la calidad del aire percibidas en la ciudad/colonia/plantel educativo. Lo anterior permite sugerir que en la política ambiental debe incorporarse el componente de la focalización, de tal manera que los programas ambientales sean más eficientes en el ámbito local.OBJECTIVE: Analyze the relations established between air pollution and health-disease-death in a sample of students in Mexico City. MATERIAL AND METHODS: Survey of 1274 students from 14 secondary schools in five areas in Mexico City was conducted between March and April of 2003. We used a multi-stage sampling, based in a basic geostatistical areas (AGEB. RESULTS: A total of 84.4% believed that Mexico City has a high, or very high air pollution; that valuation decreases as it approaches the most immediate place in which the students live. The health risks range from effects on respiratory health, 66.9%, to other effects on daily life, 2

  6. 9 CFR 381.91 - Contamination.

    Science.gov (United States)

    2010-01-01

    ... § 381.91 Contamination. (a) Carcasses of poultry contaminated by volatile oils, paints, poisons, gases, scald vat water in the air sac system, or other substances which render the carcasses adulterated shall... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Contamination. 381.91 Section...

  7. NSF-RANN trace contaminants abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Copenhaver, E.D.; Harnden, D.S. (eds.)

    1976-10-01

    Specific areas of interest of the Environmental Aspects of Trace Contaminants Program are organic chemicals of commerce, metals and organometallic compounds, air-borne contaminants, and environmental assay methodology. Fifty-three abstracts of literature on trace contaminants are presented. Author, keyword, and permuted title indexes are included. (HLW)

  8. Anti-airborne-molecular-contamination technology in clean rooms; Kukichu no kagaku osen no teigen taisaku

    Energy Technology Data Exchange (ETDEWEB)

    Sakata, S.; Sato, K.; Takahashi, H.; Okada, T.

    1998-07-31

    As for, countermeasures for chemical contaminants in a cleanroom air, the technical development has progressed earnestly since T top phenomenon of photo-amplified resist with basic gas due to atmosphere was pointed out in 1991 by MacDonald. Airborne-Molecular-Contamination (AMC) is classified into acids, bases, condensables, and dopants. According to SEMATECH no 95052812A-TR, condensable are defined as silicones or hydrocarbons with a boiling point greater than or equal to 150 degC. Water-soluble gaseous contaminants in outdoor air coming into cleanrooms are removed with a water spray equipment. AMC originated from circulating air in cleanrooms are prevented using various chemical filters. Conventional chemical filters made of activated charcoal, however, have several defects. Ceramic chemical filters developed by the authors are nonflammable, and consist of inorganic materials without any volatile organic matters and without alkaline metal and so on, and they have high removal efficiencies of condensable. 15 refs., 12 figs., 3 tabs.

  9. Structural and chemical changes in ultra-high-molecular-weight polyethylene due to gamma radiation-induced crosslinking and annealing in air.

    Science.gov (United States)

    Viano, A M; Spence, K E; Shanks, M A; Scott, M A; Redfearn, R D; Carlson, C W; Holm, T A; Ray, A K

    2007-01-01

    Ultra-High-Molecular-Weight-Polyethylene (UHMWPE) is the material of choice for one of the articulating surfaces in many total joint replacements, notably hip and knee prostheses. The various methods used by the orthopaedic biomaterials industry to sterilize and anneal UHMWPE components, and the resulting oxidation and crosslinking, affect the mechanical wear resistance properties in ways still unknown at the microscopic and molecular levels. Transmission electron microscopy and chemical pyrolysis were used to quantify crosslinking induced by gamma irradiation and annealing in air. Changes in lamellar stacking and the amount of crosslinking suggest two types of crosslinking: relatively unstable crosslinks in the amorphous region initially resulting from gamma irradiation which are later replaced by more thermally stable crosslinks resulting from rearrangements at the annealing temperature. Lamellar mobility, the ability of crystalline lamellae to flow in the material, is enhanced during the transition from one type of bond to the other, and this appears to optimize near eight hours of annealing time. Results from decomposition and percent crystallinity measurements provide further support for this theory.

  10. A practical approach to estimate emission rates of indoor air pollutants due to the use of personal combustible products based on small-chamber studies.

    Science.gov (United States)

    Szulejko, Jan E; Kim, Ki-Hyun

    2016-02-01

    As emission rates of airborne pollutants are commonly measured from combusting substances placed inside small chambers, those values need to be re-evaluated for the possible significance under practical conditions. Here, a simple numerical procedure is investigated to extrapolate the chamber-based emission rates of formaldehyde that can be released from various combustible sources including e-cigarettes, conventional cigarettes, or scented candles to their concentration levels in a small room with relatively poor ventilation. This simple procedure relies on a mass balance approach by considering the masses of pollutants emitted from source and lost through ventilation under the assumption that mixing occurs instantaneously in the room without chemical reactions or surface sorption. The results of our study provide valuable insights into re-evaluation procedure of chamber data to allow comparison between extrapolated and recommended values to judge the safe use of various combustible products in confined spaces. If two scented candles with a formaldehyde emission rate of 310 µg h(-1) each were lit for 4 h in a small 20 m(3) room with an air change rate of 0.5 h(-1), then the 4-h (candle lit) and 8-h (up to 8 h after candle lighting) TWA [FA] were determined to be 28.5 and 23.5 ppb, respectively. This is clearly above the 8-h NIOSH recommended exposure limit (REL) time weighted average of 16 ppb.

  11. SAROTA: application of specific absorption rate (SAR) and over-the-air (OTA) data for the characterization of the real-life exposure due to mobile phones

    Science.gov (United States)

    Monebhurrun, Vikass

    2013-04-01

    The RF exposure level of a mobile phone is quantified by the measurement of the specific absorption rate (SAR) under laboratory conditions. The SAR which is measured while the mobile phone is operated at maximum power level does not reflect the real-life exposure scenario since the mobile phone typically re-adjusts its power level and frequency depending on the quality of the communication link with the nearest base station. The choice of a low RF exposure device based on the comparison of the relative SAR values of mobile phones can be misleading. The real-life RF exposure also depends on the over-the-air (OTA) performance of the mobile phone. Taken independently, the two sets of data do not allow a straightforward comparison of the global RF performance amongst mobile phones. A unique and simple parameter denoted as the SAROTA index is proposed for the characterization of mobile phones with regard to both RF exposure and OTA performance. The SAROTA index provides the real-life exposure index of the mobile phone.

  12. The lichen Parmelia physodes (L. Ach. as indicator for determination of the degree of atmospheric air pollution in the area contaminated by flourine and sulphur dioxide emission

    Directory of Open Access Journals (Sweden)

    M. Świeboda

    2015-01-01

    Full Text Available On the area involved in the influence of conteminations emitted by the aluminium works and electric power plant, the degree of atmospheric air pollution was evaluated on the basis of the behaviour of healthy thallus of the lichen Parmelia physodes, analysis of fluorine and sulphur content in this thallus and in the bark substrate and the F and SO2 concentrations in the air.

  13. Do perceived job insecurity and annoyance due to air and noise pollution predict incident self-rated poor health? A prospective analysis of independent and joint associations using a German national representative cohort study

    Science.gov (United States)

    Riedel, Natalie; Loerbroks, Adrian; Bolte, Gabriele; Li, Jian

    2017-01-01

    Background Current economic and social change has contributed to increasing job insecurity and traffic-related pollution in residential areas. Both job insecurity and exposure to noise and air pollution are known determinants of population health and can concur in peoples' lives. This may hold true particularly for socially disadvantaged subpopulations. Nevertheless, the potential independent and joint links of those exposures to health have been rarely examined so far. We aimed to contribute to the scarce body of evidence. Methods Information on perceived job insecurity and exposures to noise and air pollution as expressed by annoyance as well as on self-rated health were gathered from 2 waves of the population-based German Socio-Economic Panel (2009 and 2011, N=6544). We performed multivariable Poisson regression to examine the independent and joint risk of poor health in 2011 by perceived job insecurity and annoyance due to noise and air pollution in 2009. Results After the 2-year follow-up in 2011, 571 (8.7%) participants rated their health as poor. The risk of reporting incident poor health was increased by roughly 40% in employees reporting high versus low perceived job insecurity and annoyance due to noise and air pollution, respectively. This risk increased when both exposures were present at higher levels (risk ratio=1.95 (1.49 to 2.55)). Conclusions Work-related and environmental exposures may accumulate and have a joint health impact. Elaboration on the link between occupational and residential exposures is warranted in the light of their concurrence and their implications for health inequities. PMID:28115332

  14. Fermilab experience of post-annealing losses in SRF niobium cavities due to furnace contamination and the ways to its mitigation: a pathway to processing simplification and quality factor improvement

    CERN Document Server

    Grassellino, A; Crawford, A; Melnychuk, O; Rowe, A; Wong, M; Cooper, C; Sergatskov, D; Bice, D; Trenikhina, Y; Cooley, L D; Ginsburg, C; Kephart, R D

    2013-01-01

    We investigate the effect of high temperature treatments followed by only high-pressure water rinse (HPR) of superconducting radio frequency (SRF) niobium cavities. The objective is to provide a cost effective alternative to the typical cavity processing sequence, by eliminating the material removal step post furnace treatment while preserving or improving the RF performance. The studies have been conducted in the temperature range 800-1000C for different conditions of the starting substrate: large grain and fine grain, electro-polished (EP) and centrifugal barrel polished (CBP) to mirror finish. An interesting effect of the grain size on the performances is found. Cavity results and samples characterization show that furnace contaminants cause poor cavity performance, and a practical solution is found to prevent surface contamination. Extraordinary values of residual resistances ~ 1 nOhm and below are then consistently achieved for the contamination-free cavities. These results lead to a more cost-effective ...

  15. [Clinical and epidemiological aspects of enteritis due to Salmonella hadar. II. Environmental contamination by Salmonella hadar in Shizuoka Prefecture--studies on the feasibility of reducing S. hadar infection].

    Science.gov (United States)

    Mochizuki, Y; Masuda, H; Kanazashi, S; Hosoki, Y; Itoh, K; Ohishi, K; Nishina, T; Handa, Y; Shiozawa, K; Miwa, Y

    1992-01-01

    A systematic examination was performed for environmental food contamination by Salmonella in poultry farms, broiler chickens, broiler processing plants and meat on the market. Salmonella was isolated from 219 of 1197 samples and the serotypes showed a wide distribution. (Table 1-1). S. hadar accounted for 37.1% (96) of all isolations (259). The contamination rate of broiler chickens on arrival at broiler processing plants is relatively low. However, in the broiler processing plants, containers, processing machinery, cooling water and slaughters were highly contaminated by Salmonella, S. hadar being the most prominent serotype in the plants. 64% of chicken meat on the market was contaminated by Salmonella, S. hadar being the second most prominent serotype. 11% of the pork and none of the beef or horseflesh was contaminated by Salmonella. These results indicate that poultry is the main source of S. hadar infection in humans. However, no S. hadar was isolated from cultures of 119 samples of feed for chickens from each delivery (Table 1-1). Thus, as the main source of infection by S. hadar of broiler chickens, an association with the feed seems to be ruled out. S. hadar was isolated at three of 18 poultry farms within Shizuoka Prefecture. Follow-up studies were performed at the three poultry farms which revealed that in two of them, Salmonella was completely eradicated on completion of disinfection. In the other one farm, which is still being disinfected, various strains of Salmonella including S. hadar still survived. We conclude that the main cause of the problem is the magnification of contamination of Salmonella-free material during the process at the broiler processing plants.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. [On the question of occurrence and the problem of hygiene rating of fungal air pollution of the environment of residential and public buildings].

    Science.gov (United States)

    Gubernskiĭ, Iu D; Beliaeva, N N; Kalinina, N V; Mel'nikova, A I; Chuprina, O V

    2013-01-01

    Comprehensive sanitary examinations of fungal pollution of the environment of residential and public buildings were performed. There is established the occurrence of sensitization of the population associated with the fungal contamination of the wallings of buildings and presence of viable mold spores in the indoor air environment. Major factors determining the degree of fungal contamination of indoor environments: increasing humidity of indoor air due to leaks and bays, the area of enclosure structures and the temperature factor have been identified.

  17. Naphthalene contamination of sterilized milk drinks contained in low-density polyethylene bottles. Part 2. Effect of naphthalene vapour in air.

    Science.gov (United States)

    Lau, O W; Wong, S K; Leung, K S

    1995-04-01

    A survey on naphthalene vapour in air was conducted, revealing that the ambient atmosphere contained concentrations of naphthalene in the range of 0.005-0.100 mg m-3. The level of naphthalene vapour in air increased to 0.35 and 4.00 mg m-3 in places exposed to lacquer paint and naphthalene-based moth-repellent, respectively. The effect of naphthalene vapour in air on milk drinks contained in low-density polyethylene (LDPE) bottles was assessed. A mathematical model was suggested to describe the migration of naphthalene from the atmosphere into milk. The model was proved to be valid for milk drinks exposed to naphthalene-based moth-repellent during storage. Moreover, the extent of migration was found to increase with the fat content of foods, which might be ascribed to an increase in diffusion, in addition to the kinetic factor, that affects naphthalene migration.

  18. Comparison between Different Air Distribution Systems

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    The aim of an air conditioning system is to remove excess heat in a room and replace room air with fresh air to obtain a high air quality. It is not sufficient to remove heat and contaminated air, it is also necessary to distribute and control the air movement in the room to create thermal comfort...

  19. Injuries due to firearms and air guns among U.S. military members not participating in overseas combat operations, 2002-2011.

    Science.gov (United States)

    2012-09-01

    During 2002-2011, active component U.S. service members sustained 4,657 firearm-related injuries in circumstances other than deployment to the wars in Iraq/Afghanistan; 35 percent of the injuries were fatal. The highest firearm-related injury rates reflected service members in law enforcement/security and combat occupations. Of fatal injuries, 28 percent and 24 percent were suicides and homicides, respectively; among service members 30 and older, 84 percent of noncombat firearm-related deaths were suicides and 14 percent were homicides. In circumstances other than war, rates of both fatal and nonfatal firearm- related injuries are much lower among military members than civilian males aged 18-44. During the period, rates of nonfatal firearm-related injuries among non-deployed military members increased sharply, peaking in 2008. The trend reflects that among U.S. civilian males aged 18-44. However, firearm-related fatality rates were stable among civilians but increased among military members. The increase in rates of firearm-related fatalities among non-deployed military members reflects the increase in rates of suicides by firearms. Rates of injuries due to BB, pellet or paintball guns also increased during the period.

  20. A new method for calculation of an air quality index

    Energy Technology Data Exchange (ETDEWEB)

    Ilvessalo, P. [Finnish Meteorological Inst., Helsinki (Finland). Air Quality Dept.

    1995-12-31

    Air quality measurement programs in Finnish towns have expanded during the last few years. As a result of this it is more and more difficult to make use of all the measured concentration data. Citizens of Finnish towns are nowadays taking more of an interest in the air quality of their surroundings. The need to describe air quality in a simplified form has increased. Air quality indices permit the presentation of air quality data in such a way that prevailing conditions are more easily understandable than when using concentration data as such. Using an air quality index always means that some of the information about concentrations of contaminants in the air will be lost. How much information is possible to extract from a single index number depends on the calculation method. A new method for the calculation of an air quality index has been developed. This index always indicates the overstepping of an air quality guideline level. The calculation of this air quality index is performed using the concentrations of all the contaminants measured. The index gives information both about the prevailing air quality and also the short-term trend. It can also warn about the expected exceeding of guidelines due to one or several contaminants. The new index is especially suitable for the real-time monitoring and notification of air quality values. The behaviour of the index was studied using material from a measurement period in the spring of 1994 in Kaepylae, Helsinki. Material from a pre-operational period in the town of Oulu was also available. (author)

  1. Long-term experiment on in-situ sanitation of a MHC/BTEX contamination: Effectivity of air sparging and denitrification in the saturated zone; Langzeitversuch zur In situ-Sanierung einer MKW/BTEX Kontamination: Effektivitaet von Air Sparging und Denitrifikation in der gesaettigten Zone

    Energy Technology Data Exchange (ETDEWEB)

    Wuerdemann, H. [Umwelt-Geotechnik, GeoForschungsZentrum Potsdam (Germany); Hoch, S.; Bieberstein, A. [Univ. Karlsruhe (T.H.) (Germany). Inst. fuer Bodenmechanik und Felsmechanik

    2005-07-01

    In a tank farm, combined methods for in-situ sanitation were tested for a period of about 8.5 years. Both the partly saturated and the saturated zone were contaminated, so a combination of in-situ and on-site processes were used. In the partly saturated zone, biodegradation of pollutants was enhanced by oxygen supply. In the saturated zone, a water cycle was initiated for providing the soil with electron acceptors (O{sub 2} Nd NO{sub 3}). In view of the high oxygen consumption, further O{sub 2} ws supplied to the saturated zone by air sparging. (orig.)

  2. Indoor and Outdoor Air Contaminations Relationship and Measures of Improving Indoor Air Quality%室内外空气污染物的耦合关系及提高室内空气品质的措施

    Institute of Scientific and Technical Information of China (English)

    肖明星; 耿世彬; 陈莎莎; 马奕炜

    2012-01-01

    利用几种不同的物理模型对室内外空气污染物的耦合关系进行了数学表达,分析了空气过滤器的空气净化原理,讨论了位于不同处理过程的过滤器对于提高室内空气品质(IAQ)的作用。%This article use several different physical model to describe coupling relationship between indoor and outdoor air pollution ,analysis the principle of the air filter air purification, discuss all the filters' roles in improving IAQ.

  3. Kentucky Department for Natural Resources and Environmental Protection permit application for air contaminant source: SRC-I demonstration plant, Newman, Kentucky. Supplement I. [Additional information on 38 items requested by KY/DNREP

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, Jr., John F.

    1981-02-13

    In response to a letter from KY/DNREP, January 19, 1981, ICRC and DOE have prepared the enclosed supplement to the Kentucky Department for Natural Resources and Environmental Protection Permit Application for Air Contaminant Source for the SRC-I Demonstration Plant. Each of the 38 comments contained in the letter has been addressed in accordance with the discussions held in Frankfort on January 28, 1981, among representatives of KY/DNREP, EPA Region IV, US DOE, and ICRC. The questions raised involve requests for detailed information on the performance and reliability of proprietary equipment, back-up methods, monitoring plans for various pollutants, composition of wastes to flares, emissions estimates from particular operations, origin of baseline information, mathematical models, storage tanks, dusts, etc. (LTN)

  4. Does acute led (Pb) contamination influence membrane fatty acid composition and freeze tolerance in intertidal blue mussels in arctic Greenland?

    DEFF Research Database (Denmark)

    Thyrring, Jakob; Juhl, Bodil Klein; Holmstrup, Martin;

    2015-01-01

    In their natural habitats, organisms are exposed to multiple stressors. Heavy metal contamination stresses the cell membrane due to increased peroxidation of lipids. Likewise, sub-zero air temperatures potentially reduce membrane functionality in ectothermal animals. We tested if acute lead (Pb...... tolerance and does not induce membrane damage in terms of persistent lipid peroxidation....

  5. Environmental contamination, product contamination and workers exposure using a robotic system for antineoplastic drug preparation.

    Science.gov (United States)

    Sessink, Paul J M; Leclercq, Gisèle M; Wouters, Dominique-Marie; Halbardier, Loïc; Hammad, Chaïma; Kassoul, Nassima

    2015-04-01

    Environmental contamination, product contamination and technicians exposure were measured following preparation of iv bags with cyclophosphamide using the robotic system CytoCare. Wipe samples were taken inside CytoCare, in the clean room environment, from vials, and prepared iv bags including ports and analysed for contamination with cyclophosphamide. Contamination with cyclophosphamide was also measured in environmental air and on the technicians hands and gloves used for handling the drugs. Exposure of the technicians to cyclophosphamide was measured by analysis of cyclophosphamide in urine. Contamination with cyclophosphamide was mainly observed inside CytoCare, before preparation, after preparation and after daily routine cleaning. Contamination outside CytoCare was incidentally found. All vials with reconstituted cyclophosphamide entering CytoCare were contaminated on the outside but vials with powdered cyclophosphamide were not contaminated on the outside. Contaminated bags entering CytoCare were also contaminated after preparation but non-contaminated bags were not contaminated after preparation. Cyclophosphamide was detected on the ports of all prepared bags. Almost all outer pairs of gloves used for preparation and daily routine cleaning were contaminated with cyclophosphamide. Cyclophosphamide was not found on the inner pairs of gloves and on the hands of the technicians. Cyclophosphamide was not detected in the stationary and personal air samples and in the urine samples of the technicians. CytoCare enables the preparation of cyclophosphamide with low levels of environmental contamination and product contamination and no measurable exposure of the technicians.

  6. ATEMAC - Usage of passive tracer gases for air flow and indoor pollution measurements; ATEMAC - Application des traceurs passifs pour l'etude des mouvements d'air et de contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Roulet, C.-A.

    2001-07-01

    Tracer gases are used in Switzerland for more than 15 years for air flow and ventilation rate measurements as well as for the simulation of air pollutants. The measurement equipment available in Switzerland is accurate and well performing, but rather expensive and voluminous. Moreover, preparing and carrying out the measurements is relatively time consuming. The general objective of the project was the development of a simple, efficient and cheap methodology for the measurement of air flow rates in buildings. Originally, it was thought that a procedure developed at Brookhaven National Laboratory could be transferred to Switzerland. However, measurements at the Swiss Federal Laboratories for Materials Testing and Research (EMPA) indicated that the used tracer gases were adsorbed in an unpredictable way by building materials and pieces of furniture, leading to a massive overestimation of air flow rates. Accordingly, the research work plan was modified in the course of 2000 in order to explore three alternative approaches: (1) the aerosol method, using a photo-ionisation particulate counter; (2) identification and evaluation of new analyzer types; (3) analysis of CO{sub 2} concentration recordings. The conclusions were: (1) the aerosol method is not yet reliable. (2) On the market, a number of analyzers are available at a reasonable price and new devices are currently being developed, especially at the Swiss Federal Institutes of Technology. (3) In numerous cases, the CO{sub 2} concentration methodology is easy to apply, particularly since a computer code for easy interpretation of the concentration measurements was developed and validated. Moreover, the measurements give an estimate of the air-tightness of the building envelope. (author)

  7. Study of particle-flow interactions: applications in the analysis of air contamination in bio-climatology and urban pollution; Etude de l'interaction particules-ecoulement: applications a l'analyse de la contamination aerienne en bioclimatologie et en pollution urbaine

    Energy Technology Data Exchange (ETDEWEB)

    Rambert, A.

    1998-07-01

    The study of particle-flow interaction sheds light on air contamination in bio-climatology and on urban pollution. In both phenomena the stage of particle releasing plays an important role. We propose a new approach of the simulation of the releasing of particles that are situated in the laminar sub-layer of a turbulent boundary layer. We have developed an experimental installation designed to characterize particle releasing experimentally. Laser velocimetry based on Doppler effect has been used to measure spores velocity, this method does not interact with the system and is very accurate. The knowledge of the velocity field and of the size of the particles allows a better understanding of particle transport in a fixed flow configuration. We have studied another type of particle-flow interaction, it concerns the scattering of polluting agents in a canyon street. This interaction has been simulated by an interaction between a boundary layer and a notch.

  8. Expedition surveys of the sea water and atmospheric air radioactive contamination in the Russian Far Eastern coastal areas and in the North Western Pacific in connection with accident at the "Fukushima-1" NPP

    Science.gov (United States)

    Nikitin, Aleksandr; Shershakov, Vjacheslav

    2013-04-01

    In accordance with decision of the Russian Federation Federal Service on Hydrometeorology and Environmental Monitoring (Roshydromet) on assessment of the sea water and atmospheric air radioactive contamination in the Sea of Japan and in Kurile-Kamchatka region of the Pacific ocean, in connection with accident at the "Fukushima-1" NPP, two expedition surveys were conducted in the Sea of Japan and in the North-Western Pacific (in the area adjacent to Kurile Islands and in the Kuroshio current selected area (coordinates 36°00'-39°33' n., 146°33'-150°00' e.): first survey April - May 2011, second survey August-September 2012. Both surveys were conducted under the Russian Geographical Society patronage. The results of measurements of Cs-137, Cs-134, Sr-90, Pu-239,240 and H-3 concentrations in the sea water samples and I-131, Cs-137 and Cs-134 concentrations in atmospheric aerosol samples are presented and discussed. The data received allowed to conclude that the levels of contamination by products of accidental releases and discharges at "Fukushima-1" NPP observed in investigated water areas near the Russian Federation coast of the Sea of Japan and of the Kurile- Kamchatka region of the Pacific ocean have no hazard. However, these expedition surveys revealed large-scale contamination by Cs-137 and Cs-134 of water areas of the North-Western Pacific in the investigated region of the Kuroshio current. The Cs-137 concentration in sea water at a distance about 400 km from accidental NPP in April-May, 2011 reached 30 Bq/m3, which approximately 20 times exceed preaccidental level, and it was found that water mass till more than 100 m below the surface was contaminated. For correct estimation of current and potential consequences of the "Fukushima-1" accident for the Far-Eastern water areas a special study is reasonable to perform of transport with marine currents of products of accidental releases and discharges at "Fukushima-1" NPP.

  9. AIR RADIOACTIVITY MONITOR

    Science.gov (United States)

    Bradshaw, R.L.; Thomas, J.W.

    1961-04-11

    The monitor is designed to minimize undesirable background buildup. It consists of an elongated column containing peripheral electrodes in a central portion of the column, and conduits directing an axial flow of radioactively contaminated air through the center of the column and pure air through the annular portion of the column about the electrodes. (AEC)

  10. Comparison of Air Pollution in Metropolises in China (Beijing) and Japan (Osaka and Nagoya) on the Basis of the Levels of Contaminants and Mutagenicity.

    Science.gov (United States)

    Coulibaly, Souleymane; Minami, Hiroki; Abe, Maho; Furukawa, Nami; Ono, Ryo; Hasei, Tomohiro; Toriba, Akira; Tang, Ning; Hayakawa, Kazuichi; Funasaka, Kunihiro; Asakawa, Daichi; Ikemori, Fumikazu; Watanabe, Masanari; Honda, Naoko; Wakabayashi, Keiji; Watanabe, Tetsushi

    2016-01-01

    Public concern regarding the transport of air pollutants from mainland East Asia to the leeward area by the prevailing westerlies in spring and winter monsoon has been growing in recent years. We collected total suspended particle (TSP) in Beijing, a metropolis of China located windward of Japan, in spring (late February 2011-May 2011) and in winter (November 2012-early February 2013), then analyzed metals, ions, and organic compounds and mutagenicity, and compared the pollution levels with samples collected at two Japanese metropolises (Osaka and Nagoya) during the same periods. The medians of concentration of TSP and other factors in Beijing were much larger than those in the Japanese metropolises. Especially, the concentrations of polycyclic aromatic hydrocarbons (PAHs) were remarkably high in Beijing in winter, and the median of total PAHs concentration in Beijing was 62-63 times larger than that in the Japanese sites. The mutagenicity of TSP from Beijing toward Salmonella typhimurium YG1024, with and without a mammalian metabolic system (S9 mix), was 13-25 times higher than that from the Japanese sites in winter. These results suggest that air pollution levels in Beijing are very high compared with those at the two Japanese metropolises we evaluated. The diagnostic ratios of PAHs and nitrated polycyclic aromatic hydrocarbons (NPAHs) suggest that the major sources of PAHs and NPAHs in Beijing are different from those at the two Japanese sites in winter, and that the major source in Beijing is coal/biomass combustion.

  11. Air protection strategy in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Blaszczyk, B.

    1995-12-31

    Air quality is one of the basic factors determining the environmental quality and influencing the life conditions of people. There is a shortage of proper quality air in many regions of Poland. In consequence, and due to unhindered transport, air pollution is the direct cause of losses in the national economy (reduction of crops, losses in forestry, corrosion of buildings and constructions, worsening of people`s health). Poland is believed to be one of the most contaminated European countries. The reason for this, primarily, is the pollution concomitant with energy-generating fuel combustion; in our case it means the use of solid fuels: hard coal and lignite. This monocultural economy of energy generation is accompanied by low efficiency of energy use (high rates of energy loss from buildings, heat transmission pipelines, energy-consuming industrial processes). This inefficiency results in the unnecessary production of energy and pollution. Among other reasons, this results from the fact that in the past Poland did not sign any international agreements concerning the reduction of the emission of pollution. The activities aimes at air protection in Poland are conducted based on the Environmental Formation and Protection Act in effect since 1980 (with many further amendments) and the The Ecological Policy of the state (1991). The goals of the Polish air pollution reduction program for the period 1994-2000 are presented.

  12. Parameter sets for upper and lower bounds on soil-to-indoor-air contaminant attenuation predicted by the Johnson and Ettinger vapor intrusion model

    Science.gov (United States)

    Tillman, Fred D.; Weaver, James W.

    Migration of volatile chemicals from the subsurface into overlying buildings is known as vapor intrusion (VI). Under certain circumstances, people living in homes above contaminated soil or ground water may be exposed to harmful levels of these vapors. A popular VI screening-level algorithm widely used in the United States, Canada and the UK to assess this potential risk is the "Johnson and Ettinger" (J&E) model. Concern exists over using the J&E model for deciding whether or not further action is necessary at sites, as many parameters are not routinely measured (or are un-measurable). Using EPA-recommended ranges of parameter values for nine soil-type/source depth combinations, input parameter sets were identified that correspond to bounding results of the J&E model. The results established the existence of generic upper and lower bound parameter sets for maximum and minimum exposure for all soil types and depths investigated. Using the generic upper and lower bound parameter sets, an analysis can be performed that, given the limitations of the input ranges and the model, bounds the attenuation factor in a VI investigation.

  13. A Breath of Fresh Air: Addressing Indoor Air Quality

    Science.gov (United States)

    Palliser, Janna

    2011-01-01

    Indoor air pollution refers to "chemical, biological, and physical contamination of indoor air," which may result in adverse health effects (OECD 2003). The causes, sources, and types of indoor air pollutants will be addressed in this article, as well as health effects and how to reduce exposure. Learning more about potential pollutants in home…

  14. Microsensors for rapid estimation of the degree of contamination due to organic matter in waste waters; Microsensores para la estimacion rapida del grado de contaminacion por materia organica de las aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    Orozco Holguin, J.; Fernandez Sanchez, C.; Jimenez Jorquera, C.

    2008-07-01

    The chemical oxygen demand, COD, is an indicative of the contamination grade by organic matter in wastewater effluents. Its measurement is usually performed with conventional instrumentation and techniques which are time-consuming and requires highly pollutant and dangerous reagents. electrochemical oxygen demand, EOD, is proposed as an alternative parameter to COD. This works reports on a chemical microsensor as an attractive option to get this parameter, thanks to its high speed of response, robustness, feasibility and low-cost of production. The microsensor developed, modified with a conductive composite, has been characterized and used to estimate the EOD of wastewater samples coming from a production line of parenteral food and from a wine making process. (Author) 34 refs.

  15. The Improvement of Automotive Doors Design to due with the Matter of Reducing the Contamination by Traffic Tools%针对交通工具环境污染问题引发的车门改进

    Institute of Scientific and Technical Information of China (English)

    王文清; 王红蕊; 康朴川

    2005-01-01

    The environmental contamination, which is occurred by traffic tools, is regard as a serious problem. This passage takes a process of automobile door's design as an example to show the method of declining the mass of vehicle. Through which way the emissions can be reduced effectively.%交通工具造成的环境污染问题引起了社会各界的普遍关注.以车门的设计为例,展示了如何在不影响车辆的使用数据,如强度、刚度等和不增加生产成本的前提下,有效地减少车门的总重量,以达到降低汽车尾气排放污染的目的.

  16. Analysis of organic contaminants from silicon wafer and disk surfaces by thermal desorption-GC-MS

    Science.gov (United States)

    Camenzind, Mark J.; Ahmed, Latif; Kumar, Anurag

    1999-03-01

    Organic contaminants can affect semiconductor wafer processing including gate oxide integrity, polysilicon growth, deep ultraviolet photoresist line-width, and cleaning & etching steps. Organophosphates are known to counter dope silicon wafers. Organic contaminants in disk drives can cause failures due to stiction or buildup on the heads. Therefore, it is important to identify organic contaminants adsorbed on wafer or disk surfaces and find their sources so they can be either completely eliminated or at least controlled. Dynamic headspace TD-GC-MS (Thermal Desorption-Gas Chromatography-Mass Spectrometry) methods are very sensitive and can be used to identify organic contaminants on disks and wafers, in air, or outgassing from running drives or their individual components.

  17. The evaluation of microbial contamination in the working environment of tanneries

    Directory of Open Access Journals (Sweden)

    Justyna Skóra

    2014-02-01

    Full Text Available Background: Due to their animal material processing, tannery workers may be exposed to biological agents. The aim of the study was the microbial contamination assessment of tanneries with different production specifications. Health risk was estimated based on particle size distribution. Moreover, indicators of microbial contamination of tanneries were selected. Materials and Methods: The studies were conducted in 2 types of tanneries - processing raw hides and producing chrome-tanned leather. Air was sampled with MAS-100 Eco Air Sampler, leathers using RODAC Envirocheck® contact plates and swab method, microbial numbers were determined by a culture method. For the bioaerosols size distribution analysis, a six-stage Andersen sampler was used; identification was performed using microscopy and biochemical methods. Microbial contamination was identified by 16S RNA and ITS1/2 rDNA analysis for bacteria and fungi respectively. Results: The microbial number in the air ranged between 1.2×103 and 3.7×103 CFU/m3. While on the leather, it ranged between 7.6×101 and 5.5×105 CFU/100 cm2. Bacteria dominated in the tanneries (air: 51-92%, leathers: 60-100%. Results indicate that potential health risks arise from the fungal small bioaerosol particles presence (0.65-2.1 μm. Eleven indicator microorganisms were determined: B. pumilus, B. subtilis, B. cereus, C. lubricantis, C. cladosporioides, P. commune, P. echinulatum, P. chrysogenum, P. crustosum, C. parapsilosis and C. albidus. Conclusions: Microbial contamination evaluation in the tanneries showed the increased bacteria and fungi number in the air in relation to the outdoor air, which indicates an occupational inhalation risk to workers. The designated indicators of microbial contamination in the tanneries are associated with their specific and potentially pathogenic working environment. Med Pr 2014;65(1:15–32

  18. Expedition surveys of the sea water and atmospheric air radioactive contamination in the Russian Far Eastern coastal areas and in the North- Western Pacific in connection with accident at the 'Fukushima-1' NPP

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, Aleksandr; Shershakov, Viacheslav; Artemev, Georgii [Research and Production Association ' Typhoon' (RPA ' Typhoon' ), Obninsk, Kaluga Region (Russian Federation); Ramzaev, Valery [Ramzaev Saint-Petersburg Research Institute of Radiation Hygiene, Saint-Petersburg (Russian Federation); Osokin, Vladimir [V.G.Khlopin Radium institute, Saint-Petersburg (Russian Federation); Sevastianov, Aleksandr [Far Eastern Regional Hydrometeorological Research Institute, Vladivostok (Russian Federation)

    2014-07-01

    In accordance with decision of the Russian Federation Federal Service on Hydro-meteorology and Environmental Monitoring (Roshydromet) on assessment of the sea water and atmospheric air radioactive contamination in the Russian coastal areas of the Far East in connection with accident at the 'Fukushima-1' NPP in Japan, two radioecological expedition surveys were conducted onboard of research vessels of the Far Eastern Regional Hydro-meteorological Research Institute (FERHRI) of Roshydromet in the Sea of Japan and in the North-Western Pacific (in the area adjacent to Kurile Islands and in the Kuroshio current selected area (coordinates 36 deg. 00'- 39 deg. 33' n., 146 deg. 33'- 150 deg. 00' e.): first survey in April-May 2011, onboard R/V 'Pavel Gordienko', second survey in August-September 2012, onboard R/V 'Akademik Shokalsky'. Both surveys were conducted under the Russian Geographical Society patronage. The leading Russian institutions dealing with ensuring of population radiation safety and protection of environment from radioactive contamination were enlisted to investigations. The following main observations were performed during the surveys: constant measurement of gamma-radiation dose rate above the sea surface; twenty-four hour sampling of atmospheric aerosols, sea water sampling from the surface and deep water horizons with preliminary concentrating of radionuclides for onboard gamma-spectrometry and for subsequent transportation to the shore laboratories for further analysis. During the expeditions, a real-time data were received onboard of research vessels which characterize impact of input of radioactive products of the 'Fukushima-1' NPP accident on radioactive contamination of environment existed on that period (these are onboard estimates of {sup 137}Cs and {sup 134}Cs concentrations in the sea water samples and {sup 131}I, {sup 137}Cs, {sup 134}Cs content in atmospheric aerosol samples, data

  19. Trace Contaminant Control: An In-Depth Study of a Silica-Titania Composite for Photocatalytic Remediation of Closed-Environment Habitat Air

    Science.gov (United States)

    Coutts, Janelle L.

    2013-01-01

    This collection of studies focuses on a PCO system for the oxidation of a model compound, ethanol, using an adsorption-enhanced silica-TiO2 composite (STC) as the photocatalyst; studies are aimed at addressing the optimization of various parameters including light source, humidity, temperature, and possible poisoning events for use as part of a system for gaseous trace-contaminant control system in closed-environment habitats. The first goal focused on distinguishing the effect of photon flux (i.e., photons per unit time reaching a surface) from that of photon energy (i.e., wavelength) of a photon source on the PCO of ethanol. Experiments were conducted in a bench-scale annular reactor packed with STC pellets and irradiated with either a UV-A fluorescent black light blue lamp O max=365 nm) at its maximum light intensity or a UV-C germicidal lamp O. max=254 nm) at three levels of light intensity. The STC-catalyzed oxidation of ethanol was found to follow zero-order kinetics with respect to CO2 production, regardless of the photon source. Increased photon flux led to increased EtOH removal, mineralization, and oxidation rate accompanied by lower intermediate concentration in the effluent. The oxidation rate was higher in the reactor irradiated by UV-C than by UV-A (38.4 vs. 31.9 nM s-1 ) at the same photon flux, with similar trends for mineralization (53.9 vs. 43.4%) and reaction quantum efficiency (i.e., photonic efficiency, 63.3 vs. 50.1 nmol C02 mol photons-1 ). UV-C irradiation also led to decreased intermediate concentration in the effluent compared to UV -A irradiation. These results demonstrated that STC-catalyzed oxidation is enhanced by both increased photon flux and photon energy. The effect of temperature and relative humidity on the STC-catalyzed degradation of ethanol was also determined using the UV-A light source at its maximum intensity.

  20. Contamination by mercury in air of the mining district of San Martin de Loba in Bolivar's Department, Colombia; Contaminacion por mercurio en aire del distrito minero de San Martin de loba en el Departamento de Bolivar, Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Olivero V, J.; Young C, F.; Caballero G, K., E-mail: jolivero@unicartagena.edu.co [Universidad de Cartagena, Facultad de Ciencias Farmaceuticas, Grupo de Quimica Ambiental y Computacional, Calle de la Universidad 36-100, Cartagena de Indias (Colombia)

    2014-06-01

    Mercury (Hg) is a heavy metal, considered a highly toxic pollutant. In its elemental state is volatile, making it easy to transport over long distances through the atmosphere, so that environmental pollution caused by it is a serious problem worldwide. Activities such as gold mining, where metallic Hg is used, have contributed with its global distribution, affecting ecosystems and human health. The aim of this study was to determine the levels of total mercury (T-Hg) in air in gold mining areas in Southern Bolivar, particularly in the mining district of San Martin de Loba, in the municipalities of San Martin de Loba and Barranco de Loba (Mina Santa Cruz), Colombia. In situ analyses were performed by atomic absorption spectroscopy, using a portable Ra-915 + Zeeman mercury analyzer. In Mina Santa Cruz, one of the most important gold mines in Colombia, concentrations of Hg in air ranged between 163.7 ± 6.6 and 40 455 ± 2154 mg/m{sup 3}, while in the urban area of San Martin de Loba varied from 223.6 ± 20.8 to 27 140 ± 212.5 ng/m{sup 3}. In those places where an amalgam burning process was taking place at the time of the measurements, Hg concentrations reached values of 40 455 ± 2154 ng/m{sup 3}. These data imply a severe occupational exposure to Hg for operators and citizens living in cities located near mines. Therefore, it is important to regulate and control the use of Hg in gold mining, avoiding a chronic impact of the metal on the health of people and the environment. (author)

  1. Tritium in the food chain. Intercomparison of model predictions of contamination in soil, crops, milk and beef after a short exposure to tritiated water vapour in air

    Energy Technology Data Exchange (ETDEWEB)

    Barry, P. [PJS Barry (Canada)] [and others

    1996-09-01

    Future fusion reactors using tritium as fuel will contain large inventories of the gas. The possibility that a significant fraction of an inventory may accidentally escape into the atmosphere from this and other potential sources such as tritium handling facilities and some fission reactors e g, PWRs has to be recognized and its potential impact on local human populations and biota assessed. Tritium gas is relatively inert chemically and of low radiotoxicity but it is readily oxidized by soil organisms to the mixed oxide, HTO or tritiated water. In this form it is highly mobile, strongly reactive biologically and much more toxic. Models of how tritiated water vapour is transported through the biosphere to foodstuffs important to man are essential components of such an assessment and it is important to test the models for their suitability when used for this purpose. To evaluate such models, access to experimental measurements made after actual releases are needed. There have however, been very few accidental releases of tritiated water to the atmosphere and the experimental findings of those that have occurred have been used to develop the models under test. Models must nevertheless be evaluated before their predictions can be used to decide the acceptability or otherwise of designing and operating major nuclear facilities. To fulfil this need a model intercomparison study was carried out for a hypothetical release scenario. The study described in this report is a contribution to the development of model evaluation procedures in general as well as a description of the results of applying these procedures to the particular case of models of HTO transport in the biosphere which are currently in use or being developed. The study involved eight modelers using seven models in as many countries. In the scenario farmland was exposed to 1E10 Bq d/m{sup 3} of HTO in air during 1 hour starting at midnight in one case and at 10.00 a.m. in the other, 30 days before harvest of

  2. Monitoring personnel-contamination in biology cabinet with air borne microbes instrument%空气微生物检测仪对生物安全柜中人员污染的监测

    Institute of Scientific and Technical Information of China (English)

    魏贤莉; 胡良勇

    2011-01-01

    Currently, traditional sedimentation method widely used in pharmaceuticals industry and construction industry to detect personnel-contamination, one item of three biology cabinet examination indicates, was regarded as complex operation, low detection efficiency, etc. In order to improve the status, the authors employed the new multi-function instrument for air borne microbes (JWL-ⅡC) to collect and monitor the bacterial particles in biology cabinets for different laboratories. The results indicated that the new multi-function instrument for air borne microbes has the features of simple operation, excellent portability, wide application, high rate and high accuracy in comparison to traditional sedimentation method. In addition, the experimental results confirmed that the biology cabinet indeed could effectively ensure the bio-safety of operators by preventing the aerosol leakage.%目前医药行业及建筑行业对生物安全柜有关人员污染保护指标的检测普遍采用沉降法,其操作复杂、效率低,为了改变这种现状,采用新型多功能空气微生物检测仪(JWL-IIC)对各级实验室内生物安全柜关于人员保护项目中细菌进行采集和监测.结果表明:相比于沉降法而言,它不仅操作简便、便于携带,而且使用范围广、捕获率高、结果准确;实验数据还证实,生物安全柜的合理使用确实能有效防止气溶胶的泄漏,保护操作人员的生物安全.

  3. Air quality control in the ART laboratory is a major determinant of IVF success

    Science.gov (United States)

    Esteves, Sandro C; Bento, Fabiola C

    2016-01-01

    A recently published article described how a fertility center in the United States implemented air quality control to newly designed in vitro fertilization (IVF) laboratory.1 A highly-efficient air filtration was achieved by installing a centered system supplying filtered air to the IVF laboratory and related critical areas, combining air particulate and volatile organic compound (VOC) filtration. As a consequence, live birth rates were increased by improvements in air quality. This article highlights the key aspects of air contamination in the IVF context. The topic is important not only to IVF specialists but also to Andrologists due to the great number of male infertility patients referred to assisted reproductive technology (ART) treatments. The evidence is growing that laboratory air quality is paramount importance for improved IVF outcome. PMID:26585700

  4. Contaminación de carne molida con cepas de Escherichia coli shigatoxigénico (STEC provenientes de comercios minoristas de San Martín, Buenos Aires, categorizados según nivel socioeconómico Contamination of Shiga toxin-producing Escherichia coli (STEC in fresh ground beef from butcher shops in San Martin, Buenos Aires Province, among different socioeconomic strata

    Directory of Open Access Journals (Sweden)

    L Miccio

    2011-06-01

    Full Text Available Escherichia coli shigatoxigénico (STEC produce enfermedades de transmisión alimentaria, desde diarreas leves a Síndrome Urémico Hemolítico, enfermedad de impacto en Argentina. Dentro de los alimentos implicados se destaca la carne bovina insuficientemente cocida. La contaminación de la carne molida y su relación con los estratos socioeconómicos no ha sido estudiada. El objetivo de este trabajo fue identificar en muestras de carne cepas STEC y establecer su perfil de virulencia, considerando la zona socioeconómica de procedencia y la persistencia de la contaminación en el local de venta. Se seleccionó el 30% de las bocas de expendio habilitadas en cada nivel socioeconómico. Se analizaron 72 muestras provenientes de 36 carnicerías de San Martín, Buenos Aires, en dos muestreos independientes utilizando PCR múltiple para stx1/stx2 e inmunocaptura para O157 al tamizaje. Se obtuvieron 11 cepas de 26 muestras sospechosas, 7% de los aislamientos fueron STEC O157. La proporción en la contaminación ponderada fue mayor en las zonas media y baja. No se comprobó persistencia. El grado de contaminación por STEC en carne para el área estudiada fue elevado y las cepas aisladas fueron altamente virulentas. En consideración a ello es necesario implementar programas de capacitación y control para reducir los riesgos para la salud pública.Shiga toxin-producing Escherichia coli (STEC causes foodborne diseases, from mild diarrhea to hemolytic uremic syndrome which impact in Argentina. Many human infections were acquired from eating undercooked contaminated beef. The contamination of ground beef and their relation to socio-economic strata has not been studied. The aim of this study was to identify STEC in meat samples and establish virulence profile, considering the socio-economic area of origin and persistence of contamination in local sales. It was selected 30% of the butcher shop of each socioeconomic level. It was analyzed 72 samples from 36

  5. Relevant results of studies performed in North Rhine-Westfalia dealing with health effects of air pollutants due to mobile sources, compared with health effects of other urban pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Koch, E. [Ministry for Environment, Duesseldorf (Germany). Regional Planning and Agriculture

    1995-12-31

    In 1975 in North Rhine-Westfalia, Federal Republic of Germany, according to the Federal Immission Control Act, five areas with high air pollution were determined. For these areas Clean Air Plans were drawn up. Clean Air Plans shall comprise a representation of emissions and immissions established for all or specific air pollutants, information about the impacts recorded for assets worthy of protection (human beings, animals and plants, water, the atmosphere etc.), any findings obtained as to the causes and effects of such air pollution, an assessment of any forthcoming changes in emission and immission conditions, details on immission levels and characteristic immission values and the measures envisaged for the reduction and prevention of air pollution. In accordance with these requirements epidemiological investigations of adults and children were performed in connection with the Clean Air Plans

  6. Huizhou air-conditioning corps bacteria contamination and population survey report%惠州市集中空调军团菌污染现状及人群感染调查报告

    Institute of Scientific and Technical Information of China (English)

    张健; 徐励琴; 罗泽燕; 冯伟明; 曾健君; 刘燕; 严宇斌

    2009-01-01

    Objective:To investigate the status of the Legionella contamination and infection in crowd in Huizhou City,in order to constitute the prevention and control strategy of Legionella infection.Methods:186 Cooling tower water samples from central air conditioning system in Huizhou City were cultured and then Legionella was isolated and identified;The antibodies IgG against Legionella of 215 dangerous group and 152 control were detected by Enzyme-linked Immunosorbent Assay(ELISA).Results:The detection rate of Legionella pneumophilia in this survey of central air conditioning system is 51.3%,62 strains of Legionella pneumophilia were isolated,among them 37 strains were serovar LP1,and 25 strains were serovar LP2~LP14;There were 29 cases of anti-Legionella positive in the 215 dangerous group,with the positive rate of 13.4%,and there were 7 cases of anti-Legionella positive in the 152 control,with the positive rate of 4.6%;Conclusion:The water in cooling tower of central air conditioning system in Huizhou city has been contaminated seriously with Legionella,and it has already being a latent threat to the health of dangerous group,thus spatial and effective preventive measures to this potential source of infection should be taken as soon as possible.%目的:了解惠州市军团菌的污染现状及人群军团菌的感染程度,为制定预防和控制军团菌感染策略提供依据.方法:采用分离鉴定与ELISA方法,对惠州市186份集中空调冷却塔水进行军团菌分离鉴定,对215例暴露人群及152例对照人群进行军团菌抗体IgG检测.结果:本次调查集中空调嗜肺军团菌检出率为51.3%,共检出62株嗜肺军团菌,其中,LP1型37株、LP2~LP14型25株;215份暴露人群中检出军团菌抗体阳性29份,阳性率13.4%,152份对照人群中检出军团菌抗体阳性7份,阳性率4.6%.结论:惠州市集中空调冷却塔水中军团菌污染现状较为严重,已对暴露人群的健康造成潜在威胁,对这一潜

  7. Emerging contaminants in groundwater

    OpenAIRE

    Lapworth, Dan; Stuart, Marianne; HART Alwyn; Crane, Emily; Baran, Nicole

    2011-01-01

    The term ‘emerging contaminants’ (ECs) is used to cover not only newly developed compounds but also includes newly discovered compounds in the environment (often due to analytical developments), and compounds that have been recently categorised as contaminants. ECs include a huge array of different compounds (and their metabolites) that are used by society for a range of purposes and include; pharmaceuticals, pesticides, personal care products, veterinary medicines, engineered nano-materials,...

  8. Accidental Contamination with Oil during Endodontic Surgery

    Science.gov (United States)

    Plascencia, Hugo; Díaz, Mariana; Cholico, Patricia; del Real, Monserrat; Márquez-de Alba, Salvador

    2016-01-01

    The modern surgical endodontic treatment is a safe and predictable procedure with high success rate. However, several factors can retard or impede the proper healing process. Use of a high speed handpiece during hard tissues management (osteotomy and apical resection) can potentially be one of these factors. Formation of metallic debris from the surgical diamond burs, production of necrotic local tissue due to overheating and the direct liberation of air from conventional handpiece into the working area are potential irritants able to delay the tissue healing. The aim of the present article is to report the histopathological findings of the trans-operational accidental contamination with oil in the surgical area during an endodontic surgery. PMID:27790269

  9. Subsurface Contamination Control

    Energy Technology Data Exchange (ETDEWEB)

    Y. Yuan

    2001-12-12

    There are two objectives of this report, ''Subsurface Contamination Control''. The first is to provide a technical basis for recommending limiting radioactive contamination levels (LRCL) on the external surfaces of waste packages (WP) for acceptance into the subsurface repository. The second is to provide an evaluation of the magnitude of potential releases from a defective WP and the detectability of the released contents. The technical basis for deriving LRCL has been established in ''Retrieval Equipment and Strategy for Wp on Pallet'' (CRWMS M and O 2000g, 6.3.1). This report updates the derivation by incorporating the latest design information of the subsurface repository for site recommendation. The derived LRCL on the external surface of WPs, therefore, supercede that described in CRWMS M and O 2000g. The derived LRCL represent the average concentrations of contamination on the external surfaces of each WP that must not be exceeded before the WP is to be transported to the subsurface facility for emplacement. The evaluation of potential releases is necessary to control the potential contamination of the subsurface repository and to detect prematurely failed WPs. The detection of failed WPs is required in order to provide reasonable assurance that the integrity of each WP is intact prior to MGR closure. An emplaced WP may become breached due to manufacturing defects or improper weld combined with failure to detect the defect, by corrosion, or by mechanical penetration due to accidents or rockfall conditions. The breached WP may release its gaseous and volatile radionuclide content to the subsurface environment and result in contaminating the subsurface facility. The scope of this analysis is limited to radioactive contaminants resulting from breached WPs during the preclosure period of the subsurface repository. This report: (1) documents a method for deriving LRCL on the external surfaces of WP for acceptance into the

  10. Visible-Light Responsive Catalysts Using Quantum Dot-Modified TiO2 for Air and Water Purification

    Science.gov (United States)

    Coutts, Janelle L.; Hintze, Paul E.; Clausen, Christian A.; Richards, Jeffrey T.

    2014-01-01

    Photocatalysis, the oxidation or reduction of contaminants by light-activated catalysts, utilizing titanium dioxide (TiO2) as the catalytic substrate has been widely studied for trace contaminant control in both air and water applications. The interest in this process is due primarily to its low energy consumption and capacity for catalyst regeneration. Titanium dioxide requires ultraviolet light for activation due to its relatively large band gap energy of 3.2 eV. Traditionally, Hg-vapor fluorescent light sources are used in PCO reactors; however, the use of mercury precludes the use of this PCO technology in a spaceflight environment due to concerns over crew Hg exposure.

  11. A method to estimate the concentration of elements in smoke from burning vegetation growing in contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, C.E. Jr.

    1991-03-04

    The Savannah River Site has areas where soil is contaminated with metals and/or radionuclides. Many of these areas are surrounded by native vegetation which is growing adjacent to the area and where the roots have penetrated into the contaminated soil of the area. In some cases vegetation has actually invaded the contaminated area. Even though the volume of contaminated vegetation is small, there are problems associated with its disposal. Vegetation decomposes quickly after burial and the volume of buried vegetation can decrease. The voids left can lead to subsidence and possible failure of the clay cap constructed over hazardous and/or radioactive waste burial grounds. An alternative to burying the wood is to burn it and bury the ash. However, burning will introduce the contamination in the vegetation into the air where there is potential for inhalation of the contaminants. A procedure is described to assess the hazard associated with inhalation of contamination from burning of vegetation growing in contaminated soil. The procedure is applied to evaluation of the consequence of burning vegetation grown adjacent to and in the SRL Seepage Basins. The results indicate that burning the vegetation during the day could introduce a level of contaminants to the atmosphere that could cause an exposure greater than the 1 mrem recommended as negligible by the National Council on Radiation Protection and Measurements but lower than the US Department of Energy 100 mrem release guide. A scenario is also investigated where the largest volume of wood, associated with the least contaminated area, is burned. The air concentrations are significantly decreased by this strategy although the total dose commitment due to all radionuclides is still above the 1 mrem dose guide.

  12. Microbiological Contamination of Cosmetic Creams in Tehran

    Directory of Open Access Journals (Sweden)

    Keshtvarz, M. (Msc

    2014-06-01

    Full Text Available Background and Objective: Transmission of pathogens by cosmetics is one of the major health complications. Direct contact with contaminated non-standard cosmetics can have irreparable side effects for the consumers. Thus, the evaluation of microbial contamination in cosmetic products is important. The aim of this study was to assess the microbiological contamination of one of frequently used cream. Material and Methods: In the present study, 135 samples of a special moisturizing cream were randomly selected from pharmacies in Tehran. The microbial contamination assessment, sampling and culturing method were based on the protocol (No.3978 of Iranian Institute of Standard and Industrial Research. Results: sixty-two (46% out of 135 samples were contaminated. The highest and lowest contaminations observed were Pseudomonas aeruginosa and Bacillus, respectively. Conclusion: Due to the high contamination rate of cosmetic creams, we recommend extremely monitoring and controlling these products by health centers. Keywords: Cosmetics, Microbial Contamination, Pseudomonas Aeruginosa

  13. Status on contamination monitoring in China

    Energy Technology Data Exchange (ETDEWEB)

    Gou Quanlu [China Institute for Radiation Protection, Taiyuan (China)

    1997-06-01

    The air contaminated by radioactive materials in nuclear enterprises and radioactive workplaces and forming radioactive aerosol and the leakage of radioactive materials in operation cause internal exposure damage in workers. It is necessary and important to monitor air and surface contaminations for the health of public and workers, and for protecting environment. At present, many institutes engage in the studies on surface contamination monitoring in China, and the government has formulated the control limits of surface contamination in the Regulations of Radiation Protection. The monitors for surface contamination monitoring are almost home-made. The methods being used often are smear test and placing surface sample test. Scintillation counters, semiconductor detectors and G-M counters have been used for detecting alpha surface contamination. Plastic scintillator meters and thin wall/window G-M counters are used for beta surface contamination. Special detectors have been designed for monitoring low energy nuclides. The status of airborne contamination monitoring in China is reported. As the studies for future, the development of the surface contamination monitor for low energy beta nuclides, especially H-3, the monitoring methods for the special shapes of surfaces, the technology of decontamination and the calibration method and device for on-line radioactive aerosol continuous monitors are taken up. (K.I.)

  14. Automation of the monitoring in real time of the absorbed dose rate in air due to the environmental gamma radiation in Cuba; Automatizacion del monitoreo en tiempo real de la tasa de dosis absorbida en aire debido a la radiacion gamma ambiental en Cuba

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez L, O.; Capote F, E.; Carrazana G, J.A.; Manzano de Armas, J.F.; Alonso A, D.; Prendes A, M.; Zerquera, J.T.; Caveda R, C.A. [CPHR, Calle 20, No. 4113 e/41 y 47, Playa, La Habana, 11300, A.P. 6195 C.P. 10600 (Cuba); Kalberg, O. [Swedish Radiation Protection Institute (SSI) (Sweden); Fabelo B, O.; Montalvan E, A. [CIAC, Camaguey (Cuba); Cartas A, H. [CEAC, Cienfuegos (Cuba); Leyva F, J.C. [CISAT (Cuba)]. e-mail: orlando@cphr.edu.cu

    2006-07-01

    The Center of Protection and Hygiene of the Radiations (CPHR) like center rector of the National Net of Environmental Radiological Surveillance (RNVRA), it has strengthened their detection capacity and of answer before a situation of radiological emergency. The measurements of the absorbed dose rate in air due to the environmental gamma radiation in the main stations of the Net are obtained in real time and the CPHR receives the data coming from these posts at one time relatively short. To improve the operability of the RNVRA it was necessary to complete the facilities of existent monitoring using 4 automatic measurement stations with probes of gamma detection, implementing in this way a measurement system on real time. On the other hand the software were developed: GenironProbeFech, to obtain the data of the probes, DataMail for the shipment of the same ones by electronic mail and GammaRed that receives and processes the data in the rector center. (Author)

  15. Contaminants in human milk.

    Science.gov (United States)

    Olszyna-Marzys, A E

    1978-09-01

    There is a paucity of information regarding excretion of contaminants in human milk, due to experimental difficulties and until recently a general lack of interest. Because of the high fat content of milk and as its acidity is higher than that of plasma, nearly all liposoluble and basic agents consumed by the mother will be excreted in the milk. Distinction must be made between, on the one hand drugs and social toxicants such as smoking and alcohol, whose intake can be stopped or limited during pregnancy and lactation, and ecological toxicants present in a polluted environment to which the mother is exposed. Cases have occurred of heavy prenatal and postnatal intoxication of infants with hexachlorobenzene in Turkey and methylmercury in Iraq due to consumption of fungicide-treated seed wheat by pregnant and lactating mothers. Recent attention has been concentrated on contamination of milk with organochlorine compounds such as DDT and PCB's, that are found in many parts of the world. The heaviest contamination with DDT has been found in Guatemala, resulting in suckling infants consuming many times the Acceptable Daily Intake of this compound proposed by WHO, with unknown future effects.

  16. Characteristics of contaminant deposition onto a cylindrical body surrounded by porous clothing

    Science.gov (United States)

    Cho, Minki; Lee, Jinwon; Jung, Hyunsuk; Lee, Haewan; Pohang Univ of Sci; Tech Team; AgencyDefense Development Team

    2014-11-01

    In order to characterize the deposition pattern of air-borne contaminants on a human body protected by a garment, the air flow through the clothing and in the air gap between the clothing and the skin was numerically solved, and the deposition of the suspended contaminants on the skin was obtained over a wide variety of conditions-wind speed, human motion and clothing conditions. The penetrating air flow was sensitive to the pressure inside the air gap, for which a simple model was successfully formulated. Also the profile of the non-uniform deposition velocity or the Sherwood number could be well modeled based on the developing concentration boundary layer inside the air gap. The boundary layer thickness grew vary rapidly, nearly proportional to the square of the distance from the front stagnation point, which is much different from any other boundary layer studied in many engineering fields before. A rather universal function for the distribution of deposition speed over a cylindrical body was obtained, which remained valid for a very wide range of conditions. The characteristics for non-uniform and/or periodic external wind due to human motion were also analyzed. This study is supported by Agency for Defense Development.

  17. 29 CFR 1915.1000 - Air contaminants.

    Science.gov (United States)

    2010-07-01

    ... § 1915.1014 53-96-3 Acetylene 74-86-2 E Acetylene dichloride; see 1,2-Dichloroethylene Acetylene... compounds (as As) 7440-38-2 — 0.5 — Arsine 7784-42-1 0.05 0.2 — Asbestos; see 1915.1001 Azinphos-methyl 86... oxide 1303-86-2 Total dust — 15 — Boron tribromide 10294-33-4 1 10 — Boron trifluoride 7637-07-2 (C)1...

  18. 29 CFR 1910.1000 - Air contaminants.

    Science.gov (United States)

    2010-07-01

    ...-Diethylaminoethanol 100-37-8 10 50 X Diethyl ether; see Ethyl ether. Difluorodibromomethane 75-61-6 100 860 Diglycidyl... 1000 2600 Ethyl ether 60-29-7 400 1200 Ethyl formate 109-94-4 100 300 Ethyl mercaptan 75-08-1 (C)10 (C... Aldrin 309-00-2 0.25 X Allyl alcohol 107-18-6 2 5 X Allyl chloride 107-05-1 1 3 Allyl glycidyl ether...

  19. AIR POLLUTION OF URBAN AREAS

    Directory of Open Access Journals (Sweden)

    MAKAROVA V. N.

    2016-04-01

    Full Text Available Raising of problem. Any manufacturing processes related to the generation of waste. Year after year, a growing mass of waste is one of the main factors reducing the quality of the environment and destruction of natural landscapes. Industrial development inevitably enhances human impacts on the environment and disrupts the ecological balance [3]. Atmospher air is a vital element of the environment. The development of industry, the growth of cities, increasing the number of transport, active exploration of near-Earth space lead to a change in the gas composition of the atmosphere and disruption of its natural balance. Air quality affects the health of the population [5]. Without water or food a person can do for a while, but without air he can not live a few minutes, therefore saving air breathable is an urgent problem. Purpose. The results of geological studies clearly indicate that the contamination of the surface layer of the atmosphere is the most powerful permanent factor of influence on the human food chain and the environment. This problem was reflected in the scientific literature [2; 3; 6], and the second significant indicator of ecological well-being of the region is the number of generation and accumulation of waste. According to this indicator, Dnipropetrovsk region is in the lead, as relates to the industrialized regions. The idea of the article is to consider the air pollution of the urban environment in terms of the accumulation of waste in the territory of enterprises, in particular slag dumps metallurgical production. Conclusion. Slag dumps located on the premises are a significant source of air pollution urbanized areas due to the permanent nature of the spread of contamination. Slag dump of PAT "Nikopol Ferroalloy Plant" is a source of manganese, zinc, nickel emissions. As a conclusion about the magnitude of pollution of the atmospheric boundary layer can say the following: on the border of the sanitary protection zone (SPZ, in

  20. Experimental determination of re-suspension data of particle-bound radioactive materials of relevant contaminated surfaces in case of radiological emergencies for the radioactive exposure assessment of the emergency staff and affected persons due to re-suspension; Experimentelle Bestimmung von Resuspensionsdaten partikelgebundener radioaktiver Stoffe von relevanten kontaminierten Oberflaechen bei radiologischen Notfaellen zur Beurteilung einer Exposition von Einsatzpersonal und betroffenen Personen durch Resuspension

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Wolfgang; Loedding, Hubert; Lange, Florentin

    2012-01-15

    Accidental and intentional release of radioactive materials, for example in the wake of a nuclear accident, causes contamination of surfaces in the outdoor environment, in buildings and the clothing of humans. Resuspension of radioactive material from contaminated surfaces is the dominant source of radioactive inhalation exposure of first responders and emergency personnel at the accident site as well as in emergency care centres during the time period following the event. The assessment of the aerosol borne activity concentration is based on reasonable assumptions or measurements of the surface contamination and a quantitative understanding of the resuspension process. In this project the resuspension rate of respirable particles (< 10 {mu}m) and its dependence on time and influencing parameters was measured. Special emphasis was directed to the early phase after the release event. Using a versatile, small scale flow channel set-up, wind resuspension and resuspension caused by transient or continuous mechanical forces impacting on the surfaces was investigated. The flux of particles resuspended from small test surfaces was detected by an optical particle size spectrometer. Influencing parameters such properties of contaminated surfaces, wind speed, type of particle etc. could be easily varied. Well defined contaminations of the test surfaces were prepared in a settling chamber by dry and wet deposition using aerosolized dry powders of spherical (silver) and agglomerated (cerium oxide) particles, and sprays of aqueous solutions of cesium chloride, respectively. In the latter case the surface was dried after deposition of the liquid droplets leading to a surface contamination of CsCl crystals adhering stronger to the surface than particulates. The resuspension rate for surfaces contaminated by wet deposition is 2-3 orders of magnitude lower compared to the situation for dry deposition, irrespective of the resuspension mechanism. The air flow induced resuspension

  1. The delivery of organic contaminants to the Arctic food web: why sea ice matters.

    Science.gov (United States)

    Pućko, Monika; Stern, Gary A; Macdonald, Robie W; Jantunen, Liisa M; Bidleman, Terry F; Wong, Fiona; Barber, David G; Rysgaard, Søren

    2015-02-15

    For decades sea ice has been perceived as a physical barrier for the loading of contaminants to the Arctic Ocean. We show that sea ice, in fact, facilitates the delivery of organic contaminants to the Arctic marine food web through processes that: 1) are independent of contaminant physical-chemical properties (e.g. 2-3-fold increase in exposure to brine-associated biota), and 2) depend on physical-chemical properties and, therefore, differentiate between contaminants (e.g. atmospheric loading of contaminants to melt ponds over the summer, and their subsequent leakage to the ocean). We estimate the concentrations of legacy organochlorine pesticides (OCPs) and current-use pesticides (CUPs) in melt pond water in the Beaufort Sea, Canadian High Arctic, in 2008, at near-gas exchange equilibrium based on Henry's law constants (HLCs), air concentrations and exchange dynamics. CUPs currently present the highest risk of increased exposures through melt pond loading and drainage due to the high ratio of melt pond water to seawater concentration (Melt pond Enrichment Factor, MEF), which ranges from 2 for dacthal to 10 for endosulfan I. Melt pond contaminant enrichment can be perceived as a hypothetical 'pump' delivering contaminants from the atmosphere to the ocean under ice-covered conditions, with 2-10% of CUPs annually entering the Beaufort Sea via this input route compared to the standing stock in the Polar Mixed Layer of the ocean. The abovementioned processes are strongly favored in first-year ice compared to multi-year ice and, therefore, the dynamic balance between contaminant inventories and contaminant deposition to the surface ocean is being widely affected by the large-scale icescape transition taking place in the Arctic.

  2. Clean Air and Water

    Centers for Disease Control (CDC) Podcasts

    2007-04-10

    The air we breathe and the water we drink are both vital components of our health. Nevertheless, bacteria, pollutants, and other contaminates can alter life-giving air and water into health-threatening hazards. Learn about how scientists at the Centers for Disease Control and Prevention work to protect the public from air and water-related health risks.  Created: 4/10/2007 by CDC National Center for Environmental Health.   Date Released: 4/13/2007.

  3. Testing an innovative device against airborne Aspergillus contamination.

    Science.gov (United States)

    Desoubeaux, Guillaume; Bernard, Marie-Charlotte; Gros, Valérie; Sarradin, Pierre; Perrodeau, Elodie; Vecellio, Laurent; Piscopo, Antoine; Chandenier, Jacques; Bernard, Louis

    2014-08-01

    Aspergillus fumigatus is a major airborne nosocomial pathogen that is responsible for severe mycosis in immunocompromised patients. We studied the efficacy of an innovative mobile air-treatment device in eliminating A. fumigatus from the air following experimental massive contamination in a high-security room. Viable mycological particles were isolated from sequential air samples in order to evaluate the device's effectiveness in removing the fungus. The concentration of airborne conidia was reduced by 95% in 18 min. Contamination was reduced below the detection threshold in 29 min, even when the machine was at the lowest airflow setting. In contrast, during spontaneous settling with no air treatment, conidia remained airborne for more than 1 h. This indoor air contamination model provided consistent and reproducible results. Because the air purifier proved to be effective at eliminating a major contaminant, it may prove useful in preventing air-transmitted disease agents. In an experimental space mimicking a hospital room, the AirLyse air purifier, which uses a combination of germicidal ultraviolet C irradiation and titanium photocatalysis, effectively eliminated Aspergillus conidia. Such a mobile device may be useful in routine practice for lowering microbiological air contamination in the rooms of patients at risk.

  4. Organic adlayer on inorganic materials: XPS analysis selectivity to cope with adventitious contamination

    Science.gov (United States)

    Landoulsi, Jessem; Genet, Michel J.; Fleith, Sandrine; Touré, Yetioman; Liascukiene, Irma; Méthivier, Christophe; Rouxhet, Paul G.

    2016-10-01

    This work addresses the ubiquitous presence of organic contaminants at inorganic solid surfaces and the improvement of XPS analysis selectivity to cope with it. Water contact angle measurements showed that the adsorption of organic contaminants occurs readily in ambient air, and faster and more extensively under high vacuum. It is stronger on stainless steel (SS) compared to silica and is significantly reduced when SS is sterilized by autoclaving. The reliability of XPS data was evaluated (selectivity, precision, accuracy) by correlations between spectral data incorporating a large amount of results obtained with different XPS spectrometers on SS and glass samples cleaned in different ways and conditioned with several biomacromolecules. The methodology used allows a discrimination to be made between contaminants and deliberately adsorbed biomacromolecules, and offers perspectives for tracking the source of contamination. Furthermore, a discrimination can be made between oxygen from the organic adlayer and oxygen from the substrate, and the O 1s component above 532.0 eV observed for SS is shown to be due to organic contaminants rather than adsorbed water. This approach offers new perspectives to examine the interactions (displacement or not) between contaminants and compounds of interest, e.g. proteins, at the stage of the adsorption process.

  5. Assessing the fate of biodegradable volatile organic contaminants in unsaturated soil filter systems

    Science.gov (United States)

    Thullner, Martin; de Biase, Cecilia; Hanzel, Joanna; Reger, Daniel; Wick, Lukas; Oswald, Sascha; van Afferden, Manfred; Schmidt, Axel; Reiche, Nils; Jechalke, Sven

    2010-05-01

    The assessment of contaminant biodegradation in the subsurface is challenged by various abiotic processes leading to a reduction of contaminant concentration without a destructive mass removal of the contaminant. In unsaturated porous media, this interplay of processes is further complicated by volatilization. Many organic contaminants are sufficiently volatile to allow for significant fluxes from the water phase into the soil air, which can eventually lead to an emission of contaminants into the atmosphere. Knowledge of the magnitude of these emissions is thus required to evaluate the efficiency of bioremediation in such porous media and to estimate potential risks due to these emissions. In the present study, vertical flow constructed wetlands were investigated at the pilot scale as part of the SAFIRA II project. The investigated wetland system is intermittently irrigated by contaminated groundwater containing the volatile compounds benzene and MTBE. Measured concentration at the in- and outflow of the system demonstrate a high mass removal rate, but the highly transient flow and transport processes in the system challenge the quantification of biodegradation and volatilization and their contribution to the observed mass removal. By a combination of conservative solute tracer tests, stable isotope fractionation and measurements of natural radon concentration is the treated groundwater is was possible to determine the contribution of biodegradation and volatilization to total mass removal. The results suggest that for the investigated volatile compounds biodegradation is the dominating mass removal process with volatilization contributing only to minor or negligible amounts. These results can be confirmed by reactive transport simulations and were further supported by laboratory studies showing that also gas phase gradients of volatile compounds can be affected by biodegradation suggesting the unsaturated zone to act as a biofilter for contaminants in the soil air.

  6. Two multidimensional chromatographic methods for enantiomeric analysis of o,p'-DDT and o,p'-DDD in contaminated soil and air in a malaria area of South Africa.

    Science.gov (United States)

    Naudé, Yvette; Rohwer, Egmont R

    2012-06-12

    In rural parts of South Africa the organochlorine insecticide DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) is still used for malaria vector control where traditional dwellings are sprayed on the inside with small quantities of technical DDT. Since o,p'-DDT may show enantioselective oestrogenicity and biodegradability, it is important to analyse enantiomers of o,p'-DDT and its chiral degradation product, o,p'-DDD, for both health and environmental-forensic considerations. Generally, chiral analysis is performed using heart-cut multidimensional gas chromatography (MDGC) and, more recently, comprehensive two-dimensional gas chromatography (GC×GC). We developed an off-line gas chromatographic fraction collection (heart-cut) procedure for the selective capturing of the appropriate isomers from a first apolar column, followed by reinjection and separation on a second chiral column. Only the o,p'-isomers of DDT and DDD fractions from the first dimension complex chromatogram (achiral apolar GC column separation) were selectively collected onto a polydimethylsiloxane (PDMS) multichannel open tubular silicone rubber trap by simply placing the latter device on the flame tip of an inactivated flame ionisation detector (FID). The multichannel trap containing the o,p'-heart-cuts was then thermally desorbed into a GC with time-of-flight mass spectrometry detection (GC-TOFMS) for second dimension enantioselective separation on a chiral column (β-cyclodextrin-based). By selectively capturing only the o,p'-isomers from the complex sample chromatogram, (1)D separation of ultra-trace level enantiomers could be achieved on the second chiral column without matrix interference. Here, we present solventless concentration techniques for extraction of DDT from contaminated soil and air, and report enantiomeric fraction (EF) values of o,p'-DDT and o,p'-DDD obtained by a new multidimensional approach for heart-cut gas chromatographic fraction collection for off-line second dimension

  7. An experimental study of Legionella contamination in train air-conditioning%列车空调军团菌污染状况及人群感染水平的实验研究

    Institute of Scientific and Technical Information of China (English)

    闫颖; 蒋林; 马萍

    2011-01-01

    目的 了解列车空调军团菌污染状况及相关人员军团菌感染情况.方法 从合肥车辆段徐州区间的客车服务人员中,抽取列车乘务人员和站台售货人员各400名,组成实验组(乘务人员组)和对照组(站台组),做血清军团菌抗体检测;采集的风管积尘样和空调冷凝水样按规范进行军团菌分离培养和鉴定,并以PCR方法确证.结果 乘务人员组军团菌感染阳性率为53.65%,与站台组阳性率(17.3%)差异有统计学意义(P<0.01),人群感染军团菌菌型主要为Lp6;列车空调军团菌污染率为19.39%,积尘中军团菌阳性率与冷凝水中阳性率差异有统计学意义(P<0.01),检出主要菌型为Lp1.结论 列车空调风管积尘的采集更具有军团菌流行病学的代表意义,健康人群中可能存在军团菌的机会性感染.%Objective We want to understand the case of Legionella pollution in the train and related personnel Legionella infection. Method Taking the train crew and station sales staff of 400 from Xuzhou, Hefei depot service staff,composed of test and control group, ingenious and to be detected with serum antibody of Legionella. Dust samples and water samples collected from train air - conditioning condensation were treated with acid - heating, then vaccinated in GVPC to isolating and identifying,finally verificated with PCR method. Results The rate of Legionella infection is 53.65% in train service people,being compared with the site, there are significant differences ( P <0. 0l ). The main Legionella type people infected was Lp6. The contamination rate of the train air - conditioning was 19.39%. Dust in Legionella - positive rate was far higher than the positive rate of water condensation ( P <0.01 ) ,and the main type detected in experiment was Lpl. Conclusion Collecting duet dust is more representative of epidemiological significance. Legionella opportunistic infections may exist in healthy population.

  8. [Microbial air purity in hospitals. Operating theatres with air conditioning system].

    Science.gov (United States)

    Krogulski, Adam; Szczotko, Maciej

    2010-01-01

    The aim of this study was to show the influence of air conditioning control for microbial contamination of air inside the operating theatres equipped with correctly working air-conditioning system. This work was based on the results of bacteria and fungi concentration in hospital air obtained since 2001. Assays of microbial air purity conducted on atmospheric air in parallel with indoor air demonstrated that air filters applied in air-conditioning systems worked correctly in every case. To show the problem of fluctuation of bacteria concentration more precisely, every sequences of single results from successive measure series were examined independently.

  9. Quadriplegia due to lead-contaminated opium: a case report

    Directory of Open Access Journals (Sweden)

    Baigmohammadi MT

    2008-10-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Lead poisoning could be associated with gastrointestinal renal, hematologic complications and neurologic deficit."n"n Case report: The patient was an opium addict, forty one years old male, to hospital admitted with gastrointestinal signs, constipation, abdominal pain, severe weakness of upper and lower limbs without any sensory impairment and with anemia, leukocytosis, and slightly increased liver function tests. Serum level of lead was more than 200µg/dl. After treatment with dimercaprol (BAL, CaNa2EDTA for two five days sessions that followed with oral succimer for three days, signs and symptoms relieved, all laboratory tests became normal and blood level of lead reduced but the patient was discharged with quadriplegia. There was no fecal or urinary incontinence."n"n Conclusions: Because of irreversibility and severity of lead related neuronal injury, we should suspect to lead poisoning in each patient with neuronal involvement and concurrent GI and hematologic signs."n"n Keywords: Lead poisoning, motor palsy, opium, neuropathy, quadriplegia.

  10. Study on time-history characteristics of air blast wave due to great extent of roof instability%大面积顶板失稳诱发空气冲击波灾害时程特性研究

    Institute of Scientific and Technical Information of China (English)

    刘畅; 覃敏; 彭云

    2014-01-01

    rock block has a little increase and the whole catastrophic process continues for 2.89s.The wind speed reaches their extreme points as 508.1m/s after 2.1s, and the shock could reach 370m around the site of the incident;(3) because of minor re-sistance at the primary step of falling , the speed of hurricane increases drastically .At intermediate stage , the wind speed climbs slowly and gradually arrives the peak .Due to tremendous resistance in the terminal stage , the speed of hurricane decreases sharply and airflow becomes flat in the lane .( 4 ) an implementation of filling must be put into practice as soon as possible , some measures such as grooming , plugging , setting buffer layer , ground pressure monitoring and so on , should be taken to reduce the ratio of accident and harm of air blast wave .

  11. Evaluation of ergosterol content in the air of various environments.

    Science.gov (United States)

    Gutarowska, Beata; Skóra, Justyna; Pielech-Przybylska, Katarzyna

    The aim of the study was to compare the content of ergosterol in different microorganisms (bacteria, yeasts and moulds) isolated from the air as well as in six species of moulds in their different morphological forms-live mycelium, dead mycelium, and spores. Evaluation of the level of mould contamination of the air in various places using culture method and ergosterol determination was also performed. The analysis of ergosterol was carried out by gas chromatography equipped with flame ionisation detector. For evaluation of the results, analysis of variance and multiple comparison test were used. The quantity of ergosterol in the spores of various species of mould was in the range 1.9-9.4 pg/spore. The presence of yeasts and bacteria in the air does not significantly affect ergosterol concentration, in view of the low content of that sterol in their cells (max. 0.009 pg/cell for bacteria and 0.39 pg/cell for yeast). An ergosterol concentration above 1 ng per m(3) can be considered an indicator of excessive mould contamination of indoor air. Based on determination of ergosterol in the air of mouldy rooms the result obtained may be compared with the culture method, due to the 1,000 times higher concentration of ergosterol in the mycelium compared with spores. However, in the analysis of outdoor air, in view of the presence of mould mainly in the form of spores and the degradation of ergosterol by UV radiation, analysis of that compound may indicate a lower level of contamination compared with the culture method.

  12. Levamisole-contaminated cocaine : a hairy affair

    NARCIS (Netherlands)

    van der Veer, Tjeerd; Pennings, Ed; Tervaert, J W Cohen; Korswagen, Lindy-Anne

    2015-01-01

    Levamisole-contaminated cocaine can induce severe systemic vasculitis. The diagnosis can be challenging, especially when substance abuse is uncertain. We present the case of a 42-year-old woman suffering from vasculitis due to levamisole-contaminated cocaine, who persistently denied substance abuse.

  13. Monitoring and evaluation techniques for airborne contamination

    Energy Technology Data Exchange (ETDEWEB)

    Xia Yihua [China Inst. of Atomic Energy, Beijing (China)

    1997-06-01

    Monitoring and evaluation of airborne contamination are of great importance for the purpose of protection of health and safety of workers in nuclear installations. Because airborne contamination is one of the key sources to cause exposure to individuals by inhalation and digestion, and to cause diffusion of contaminants in the environment. The main objectives of monitoring and evaluation of airborne contamination are: to detect promptly a loss of control of airborne material, to help identify those individuals and predict exposure levels, to assess the intake and dose commitment to the individuals, and to provide sufficient documentation of airborne radioactivity. From the viewpoint of radiation protection, the radioactive contaminants in air can be classified into the following types: airborne aerosol, gas and noble gas, and volatile gas. In this paper, the following items are described: sampling methods and techniques, measurement and evaluation, and particle size analysis. (G.K.)

  14. Foreign body contamination during stent implantation.

    Science.gov (United States)

    Whelan, D M; van Beusekom, H M; van der Giessen, W J

    1997-03-01

    The treatment of coronary artery disease using stents has become a widely accepted technique. However, the inadvertent co-implantation of contaminating factors with the stent has received little attention. We studied histological cross-sections of stented porcine coronary arteries and observed contamination of some vessels with surgical glove powder and textile fibres. The contaminating particles were associated with a foreign body reaction. Such a reaction could delay the wound-healing response of a stented vessel and thereby prolong the period in which subacute thrombosis could occur. It is also proposed that air contamination could affect the thrombogenicity of the stent. Appropriate measures should be followed to reduce the chance of contamination occurring.

  15. Intoxicação por exposição à rapadura em três municípios do Rio Grande do Norte, Brasil: uma investigação de epidemiologia de campo Intoxication due to exposure to contaminated molasses ("rapadura" in three municipalities of the Brazilian state of Rio Grande do Norte: a field epidemiology study

    Directory of Open Access Journals (Sweden)

    Daniel Marques Mota

    2011-09-01

    Full Text Available O estudo objetivou descrever dois surtos de intoxicação por exposição à rapadura, ocorridos em três municípios do estado do Rio Grande do Norte, entre janeiro e fevereiro de 2008. Foi conduzida uma investigação epidemiológica com a realização de estudo de caso. Outras investigações, laboratorial e ambiental, complementaram o quadro de informações sobre os surtos. Foram oito casos prováveis por exposição à rapadura, dos quais cinco por consumo do produto (um evoluiu para óbito e três por proximidade física. As manifestações clínicas foram compatíveis com intoxicação por organofosforados. Outros sintomas apresentados podem estar relacionados com a presença de SO2, como rouquidão, lacrimejamento, dor nos olhos e ulceração corneana. A acetilcolinesterase eritrocitária resultou alterada para um dos pacientes que consumiu rapadura. Ocorreram dois surtos de intoxicação exógena: um por circunstância acidental e o outro, em decorrência do primeiro, por intoxicação ocupacional, cujo alimento implicado foi a rapadura contaminada com metamidofós e sulfito (SO2. A quantidade de metamidofós presente na rapadura consumida por dois casos foi 3.000 vezes maior que a ingestão diária aceitável para essa substância em humanos. Recomendam-se a adoção de medidas de saúde pública com a finalidade de minimizar a incidência de casos de intoxicação exógena e problemas decorrentes e prevenir surtos ocasionados por substâncias químicas, como as investigadas neste estudo.This study describes two poisoning outbreaks due to exposure to contaminated molasses in three municipalities of the state of Rio Grande do Norte (Northeastern Brazil between January and February 2008. Epidemiological investigation was conducted and a case study was carried out. Complementary laboratory and environmental investigations were performed to confirm outbreaks information. Eight cases were probably caused by exposure to contaminated

  16. Using radon-222 as indicator for the evaluation of the efficiency of groundwater remediation by in situ air sparging.

    Science.gov (United States)

    Schubert, Michael; Schmidt, Axel; Müller, Kai; Weiss, Holger

    2011-02-01

    A common approach for remediation of groundwater contamination with volatile organic compounds (VOCs) is contaminant stripping by means of in situ air sparging (IAS). For VOC stripping, pressurized air is injected into the contaminated groundwater volume, followed by the extraction of the contaminant-loaded exhaust gas from the vadose soil zone and its immediate on-site treatment. Progress assessment of such remediation measure necessitates information (i) on the spatial range of the IAS influence and (ii) on temporal variations of the IAS efficiency. In the present study it was shown that the naturally occurring noble gas radon can be used as suitable environmental tracer for achieving the related spatial and temporal information. Due to the distinct water/air partitioning behaviour of radon and due to its straightforward on-site detectability, the radon distribution pattern in the groundwater can be used as appropriate measure for assessing the progression of an IAS measure as a function of space and time. The presented paper discusses both the theoretical background of the approach and the results of an IAS treatment accomplished at a VOC contaminated site lasting six months, during which radon was applied as efficiency indicator.

  17. Assessment of microbiological indoor air quality in an Italian office building equipped with an HVAC system.

    Science.gov (United States)

    Bonetta, Sa; Bonetta, Si; Mosso, S; Sampò, S; Carraro, E

    2010-02-01

    The purpose of this study was to evaluate the level and composition of bacteria and fungi in the indoor air of an Italian office building equipped with a heating, ventilation and air conditioning (HVAC) system. Airborne bacteria and fungi were collected in three open-space offices during different seasons. The microbial levels in the outdoor air, supply air diffusers, fan coil air flow and air treatment unit humidification water tank were used to evaluate the influence of the HVAC system on indoor air quality (IAQ). A medium-low level of bacterial contamination (50-500 CFU/m(3)) was found in indoor air. Staphylococcus and Micrococcus were the most commonly found genera, probably due to human presence. A high fungal concentration was measured due to a flood that occurred during the winter. The indoor seasonal distribution of fungal genera was related to the fungal outdoor distribution. Significant seasonal and daily variation in airborne microorganisms was found, underlining a relationship with the frequency of HVAC system switching on/off. The results of this monitoring highlight the role of the HVAC system on IAQ and could be useful to better characterise bacterial and fungal population in the indoor air of office buildings.

  18. Window-mounted unit cleans air at hazardous waste site

    Energy Technology Data Exchange (ETDEWEB)

    Battaglia, J.M. (Independent Equipment Corp., Raritan, NJ (United States)); Sawyer, P.

    1994-07-01

    Uncontrolled hazardous waste sites present the potential for exposure to numerous airborne chemicals--both identified and unidentified. This was the case at an Elizabeth, N.J., remediation project managed by a major environmental contractor. The four-acre site housed three active manufacturing facilities and was bordered by an operation commuter railroad line. About 6,300 drums of assorted organic chemicals, mostly acid chlorides and bromides, awaited sampling and removal. In addition, 120 tanks and vessels required sampling, characterization and removal. Due to site restrictions, support trailers were located relatively close to active work areas. Damaged drums littering the site contained water-reactive, organic acid chlorides and bromides, and released slight emissions during humid or rainy conditions. Shifting winds could (and did) carry trace releases or trace contaminants toward the trailers, potentially exposing unprotected workers. Efforts were begun to alleviate even trace contaminant at levels in the remediation site's temporary office trailers. One potential solution to managing trace contaminants at the site was to use a window-mounted, air conditioner-type unit that would replenish each trailer with filtered air three times an hour, and provide positive pressure in the trailer to compensate for repeated openings and closings of doors. The design uses common, off-the-shelf components to temper the approximately 10 percent makeup air, which provides positive pressure.

  19. Air movement and perceived air quality

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Kaczmarczyk, J.

    2012-01-01

    The impact of air movement on perceived air quality (PAQ) and sick building syndrome (SBS) symptoms was studied. In total, 124 human subjects participated in four series of experiments performed in climate chambers at different combinations of room air temperature (20, 23, 26 and 28 °C), relative...... and the humidity of the room air. At a low humidity level of 30% an increased velocity could compensate for the decrease in perceived air quality due to an elevated temperature ranging from 20 °C to 26 °C. In a room with 26 °C, increased air movement was also able to compensate for an increase in humidity from 30...

  20. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, dust, ... a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  1. Remediation Measures for Posta Rât Contaminated Site (Turda

    Directory of Open Access Journals (Sweden)

    SIMULE Codruţa Violeta

    2010-08-01

    Full Text Available Waste (in the form of isomers of hexachlorocyclohexane - HCH resulting from the fabrication process oflindane of the former UCT - Turda Chemical Plants were stored, from 1954 to 1983, in 4 uncontrolled settlements fromthe Turda area, one of which is the settlement from the Posta Rât. Posta Rât contaminated site occupies an area of 4hectares, outside the built-up area of the Turda Municipality, on the left side of Aries River, summing up a quantity ofapproximately 18 500 tons of waste mixed with soil. As a result of uncontrolled storage activities, the water, air, soiland biodiversity were affected. Due to the strong negative influence of this historically contaminated site, in thismaterial our attention focuses on environmental impact assessment and identifies the most appropriate measures for thesite rehabilitation in order to restore soil functions. Based on the soil and groundwater analysis, the following measureswere proposed in order to ensure human health and environmental protection: on-site treatment of contaminated soiland groundwater, laying clean vegetal ground throughout the entire surface and replanting the retrieved land’s surfacewith trees. To ensure the success of rehabilitation action is required to install a ground water monitoring network andcarrying out a monitoring plan.

  2. Modelling heat and mass transfer in a membrane-based air-to-air enthalpy exchanger

    Science.gov (United States)

    Dugaria, S.; Moro, L.; Del, D., Col

    2015-11-01

    The diffusion of total energy recovery systems could lead to a significant reduction in the energy demand for building air-conditioning. With these devices, sensible heat and humidity can be recovered in winter from the exhaust airstream, while, in summer, the incoming air stream can be cooled and dehumidified by transferring the excess heat and moisture to the exhaust air stream. Membrane based enthalpy exchangers are composed by different channels separated by semi-permeable membranes. The membrane allows moisture transfer under vapour pressure difference, or water concentration difference, between the two sides and, at the same time, it is ideally impermeable to air and other contaminants present in exhaust air. Heat transfer between the airstreams occurs through the membrane due to the temperature gradient. The aim of this work is to develop a detailed model of the coupled heat and mass transfer mechanisms through the membrane between the two airstreams. After a review of the most relevant models published in the scientific literature, the governing equations are presented and some simplifying assumptions are analysed and discussed. As a result, a steady-state, two-dimensional finite difference numerical model is setup. The developed model is able to predict temperature and humidity evolution inside the channels. Sensible and latent heat transfer rate, as well as moisture transfer rate, are determined. A sensitive analysis is conducted in order to determine the more influential parameters on the thermal and vapour transfer.

  3. HYDROPHOBICITY OF CONTAMINATED SILICONE RUBBER SURFACES

    Institute of Scientific and Technical Information of China (English)

    Zhi-min Zheng; Cai-hong Xu; Jian Jiang; Chang-yu Ren; Wei Gao; Ze-min Xie

    2002-01-01

    Silicone rubber (SIR) shows superior performance when used outdoors, but its surface can be transformed frominherently hydrophobic to hydrophilic by the adsorption of contaminants. Al(OH)3, Al2O3, quartz powder and active carbonwere selected as authentic contaminants. Hydrophobicity of the surface was determined using contact angle measurement.The results indicate that the adsorbability of the contaminants can strongly affect the hydrophobicity of contaminated SIRsurface. The increasing rate of contact angle of specimens contaminated by Al(OH)3 was much faster than that by Al2O3 andquartz due to the adsorption of migrated low molecular weight (LMW) polydimethylsiloxanes. Specimens contaminated byactive carbon could achieve surface hydrophobicity within 15 min because active carbon has high adsorbability. Surfaces ofcontaminated ultrapure SIR, polytetrafluoroethylene (PTFE) and glass remain hydrophilic because they contain no mobileLMW components. The addition of oligomeric polydimethylsiloxanes has little effect on the hydrophobicity of contaminantscovered on SIR surface.

  4. Soil contamination of heavy metals in the Katedan Industrial Development Area, Hyderabad, India.

    Science.gov (United States)

    Govil, P K; Sorlie, J E; Murthy, N N; Sujatha, D; Reddy, G L N; Rudolph-Lund, Kim; Krishna, A K; Rama Mohan, K

    2008-05-01

    Studies on quantitative soil contamination due to heavy metals were carried out in Katedan Industrial Development Area (KIDA), south of Hyderabad, Andhra Pradesh, India under the Indo-Norwegian Institutional Cooperation Programme. The study area falls under a semi-arid type of climate and consists of granites and pegmatite of igneous origin belonging to the Archaean age. There are about 300 industries dealing with dyeing, edible oil production, battery manufacturing, metal plating, chemicals, etc. Most of the industries discharge their untreated effluents either on open land or into ditches. Solid waste from industries is randomly dumped along roads and open grounds. Soil samples were collected throughout the industrial area and from downstream residential areas and were analysed by X-ray Fluorescence Spectrometer for fourteen trace metals and ten major oxides. The analytical data shows very high concentrations of lead, chromium, nickel, zinc, arsenic and cadmium through out the industrial area. The random dumping of hazardous waste in the industrial area could be the main cause of the soil contamination spreading by rainwater and wind. In the residential areas the local dumping is expected to be the main source as it is difficult to foresee that rain and wind can transport the contaminants from the industrial area. If emission to air by the smokestacks is significant, this may contribute to considerable spreading of contaminants like As, Cd and Pb throughout the area. A comparison of the results with the Canadian Soil Quality Guidelines (SQGL) show that most of the industrial area is heavily contaminated by As, Pb and Zn and local areas by Cr, Cu and Ni. The residential area is also contaminated by As and some small areas by Cr, Cu, Pb and Zn. The Cd contamination is detected over large area but it is not exceeding the SQGL value. Natural background values of As and Cr exceed the SQGL values and contribute significantly to the contamination in the residential area

  5. Contamination monitoring in radiation protection activities in Myanmar

    Energy Technology Data Exchange (ETDEWEB)

    Thin, K.T.; Htoon, S. [Yangon Univ. (Myanmar). Dept. of Physics

    1997-06-01

    The radioactive contamination in rainwater, seawater, air, milk powder and other eatables were measured with low level counter assembly. The measured activities are found to be very low and well within the maximum permissible level. (author)

  6. DISTINGUISHING ANTHROPOGENIC AND GEOGENIC IMPACTS OF SEDIMENT CONTAMINATION

    Science.gov (United States)

    Environmental forensics is an area of scientific research that addresses contamination within the environmental media of air, water, soil and biota, and is subject to law court, arbitration, public debate, or formal argumentation. Environmental forensics involves scientific studi...

  7. Methods for Addressing Uncertainty and Variability to Characterize Potential Health Risk from Trichloroethylene-Contaminated Ground Water at Beale Air Force Base in California:Integration of Uncertainty and Variability in Pharmacokinetics and Dose-Response

    Energy Technology Data Exchange (ETDEWEB)

    Bogen, K T

    2001-05-24

    Traditional estimates of health risk are typically inflated, particularly if cancer is the dominant endpoint and there is fundamental uncertainty as to mechanism(s) of action. Risk is more realistically characterized if it accounts for joint uncertainty and interindividual variability within a systematic probabilistic framework to integrate the joint effects on risk of distributed parameters of all (linear as well as nonlinear) risk-extrapolation models involved. Such a framework was used to characterize risks to potential future residents posed by trichloroethylene (TCE) in ground water at an inactive landfill site on Beale Air Force Base in California. Variability and uncertainty were addressed in exposure-route-specific estimates of applied dose, in pharmacokinetically based estimates of route-specific metabolized fractions of absorbed TCE, and in corresponding biologically effective doses estimated under a genotoxic/linear (MA{sub G}) vs. a cytotoxic/nonlinear (MA{sub c}) mechanistic assumption for TCE-induced cancer. Increased risk conditional on effective dose was estimated under MA{sub G} based on seven rodent-bioassay data sets, and under MA{sub c} based on mouse hepatotoxicity data. Mean and upper-bound estimates of combined risk calculated by the unified approach were <10{sup -6} and 10{sup -4}, respectively, while corresponding estimates based on traditional deterministic methods were >10{sup -5} and 10{sup -4}, respectively. It was estimated that no TCE-related harm is likely to occur due to any plausible residential exposure scenario involving the site. The systematic probabilistic framework illustrated is particularly suited to characterizing risks that involve uncertain and/or diverse mechanisms of action.

  8. Methods for Addressing Uncertainty and Variability to Characterize Potential Health Risk From Trichloroethylene-Contaminated Ground Water Beale Air Force Base in California: Integration of Uncertainty and Variability in Pharmacokinetics and Dose-Response

    Energy Technology Data Exchange (ETDEWEB)

    Bogen, K.T.

    1999-09-29

    Traditional estimates of health risk are typically inflated, particularly if cancer is the dominant endpoint and there is fundamental uncertainty as to mechanism(s) of action. Risk is more realistically characterized if it accounts for joint uncertainty and interindividual variability after applying a unified probabilistic approach to the distributed parameters of all (linear as well as nonlinear) risk-extrapolation models involved. Such an approach was applied to characterize risks to potential future residents posed by trichloroethylene (TCE) in ground water at an inactive landfill site on Beale Air Force Base in California. Variability and uncertainty were addressed in exposure-route-specific estimates of applied dose, in pharmacokinetically based estimates of route-specific metabolized fractions of absorbed TCE, and in corresponding biologically effective doses estimated under a genotoxic/linear (MA{sub g}) vs. a cytotoxic/nonlinear (MA{sub c}) mechanistic assumption for TCE-induced cancer. Increased risk conditional on effective dose was estimated under MA{sub G} based on seven rodent-bioassay data sets, and under MA, based on mouse hepatotoxicity data. Mean and upper-bound estimates of combined risk calculated by the unified approach were <10{sup -6} and <10{sup -4}, respectively, while corresponding estimates based on traditional deterministic methods were >10{sup -5} and >10{sup -4}, respectively. It was estimated that no TCE-related harm is likely occur due any plausible residential exposure scenario involving the site. The unified approach illustrated is particularly suited to characterizing risks that involve uncertain and/or diverse mechanisms of action.

  9. Harvesting contaminants from liquid

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, John T.; Hunter, Scott R.

    2016-05-31

    Disclosed are examples of apparatuses for evaporative purification of a contaminated liquid. In each example, there is a vessel for storing the contaminated fluid. The vessel includes a surface coated with a layer of superhydrophobic material and the surface is at least partially in contact with the contaminated liquid. The contaminants do not adhere to the surface as the purified liquid evaporates, thus allowing the contaminants to be harvested.

  10. Using Tracer Technology to Characterize Contaminated Pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Maresca, Joseph, W., Jr., Ph.D.; Bratton, Wesley, L., Ph.D., P.E.; Dickerson, Wilhelmina; Hales, Rochelle

    2005-12-30

    The Pipeline Characterization Using Tracers (PCUT) technique uses conservative and partitioning, reactive or other interactive tracers to remotely determine the amount of contaminant within a run of piping or ductwork. The PCUT system was motivated by a method that has been successfully used to characterize subsurface soil contaminants and is similar in operation to that of a gas chromatography column. By injecting a ?slug? of both conservative and partitioning tracers at one end (or section) of the piping and measuring the time history of the concentration of the tracers at the other end (or another section) of the pipe, the presence, location, and amount of contaminant within the pipe or duct can be determined. The tracers are transported along the pipe or duct by a gas flow field, typically air or nitrogen, which has a velocity that is slow enough so that the partitioning tracer has time to interact with the contaminant before the tracer slug completely passes over the contaminate region. PCUT not only identifies the presence of contamination, it also can locate the contamination along the pipeline and quantify the amount of residual. PCUT can be used in support of deactivation and decommissioning (D&D) of piping and ducts that may have been contaminated with hazardous chemicals such as chlorinated solvents, petroleum products, radioactive materials, or heavy metals, such as mercury.

  11. Satellite material contaminant optical properties

    Science.gov (United States)

    Wood, B. E.; Bertrand, W. T.; Seiber, B. L.; Kiech, E. L.; Falco, P. M.; Holt, J. D.

    1990-03-01

    The Air Force Wright Research and Development Center and the Arnold Engineering Development Center are continuing a program for measuring optical effects of satellite material outgassing products on cryo-optic surfaces. Presented here are infrared (4000 to 700 cm(-1)) transmittance data for contaminant films condensed on a 77 K germanium window. From the transmittance data, the contaminant film refractive and absorptive indices (n, k) were derived using an analytical thin-film interference model with a nonlinear least-squares algorithm. To date 19 materials have been studied with the optical contents determined for 13 of those. The materials include adhesives, paints, composites, films, and lubricants. This program is continuing and properties for other materials will be available in the future.

  12. Thule-2003 - Investigation of radioactive contamination

    DEFF Research Database (Denmark)

    Nielsen, Sven Poul; Roos, Per

    2006-01-01

    relatively stable conditions and concentrations of plutonium in seawater and animals are low. However, the plutonium contamination of surface soil at Narssarssuk couldconstitute a small risk to humans visiting the location if radioactive particles are resuspended in the air so that they might be inhaled....

  13. Chemical oxidation of cable insulating oil contaminated soil

    NARCIS (Netherlands)

    Jinlan Xu,; Pancras, T.; Grotenhuis, J.T.C.

    2011-01-01

    Leaking cable insulating oil is a common source of soil contamination of high-voltage underground electricity cables in many European countries. In situ remediation of these contaminations is very difficult, due to the nature of the contamination and the high concentrations present. Chemical oxidati

  14. Phytoremediation Potential of Lead-Contaminated Soil Using Tropical Grasses

    Science.gov (United States)

    The global problem concerning contamination of the environment because of human activities is increasing. Most of the environmental contaminants are chemical by-products and heavy metals such as lead (Pb). Lead released into the environment makes its way into the air, soil and water. Lead contribute...

  15. Environmental contamination in Antarctic ecosystems.

    Science.gov (United States)

    Bargagli, R

    2008-08-01

    Although the remote continent of Antarctica is perceived as the symbol of the last great wilderness, the human presence in the Southern Ocean and the continent began in the early 1900s for hunting, fishing and exploration, and many invasive plant and animal species have been deliberately introduced in several sub-Antarctic islands. Over the last 50 years, the development of research and tourism have locally affected terrestrial and marine coastal ecosystems through fuel combustion (for transportation and energy production), accidental oil spills, waste incineration and sewage. Although natural "barriers" such as oceanic and atmospheric circulation protect Antarctica from lower latitude water and air masses, available data on concentrations of metals, pesticides and other persistent pollutants in air, snow, mosses, lichens and marine organisms show that most persistent contaminants in the Antarctic environment are transported from other continents in the Southern Hemisphere. At present, levels of most contaminants in Antarctic organisms are lower than those in related species from other remote regions, except for the natural accumulation of Cd and Hg in several marine organisms and especially in albatrosses and petrels. The concentrations of organic pollutants in the eggs of an opportunistic top predator such as the south polar skua are close to those that may cause adverse health effects. Population growth and industrial development in several countries of the Southern Hemisphere are changing the global pattern of persistent anthropogenic contaminants and new classes of chemicals have already been detected in the Antarctic environment. Although the Protocol on Environmental Protection to the Antarctic Treaty provides strict guidelines for the protection of the Antarctic environment and establishes obligations for all human activity in the continent and the Southern Ocean, global warming, population growth and industrial development in countries of the Southern

  16. Arsenic and dichlorvos: Possible interaction between two environmental contaminants.

    Science.gov (United States)

    Flora, Swaran J S

    2016-05-01

    Metals are ubiquitously present in the environment and pesticides are widely used throughout the world. Environmental and occupational exposure to metal along with pesticide is an area of great concern to both the public and regulatory authorities. Our major concern is that combination of these toxicant present in environment may elicit toxicity either due to additive or synergistic interactions or 'joint toxic actions' among these toxicants. It poses a rising threat to human health. Water contamination particularly ground water contamination with arsenic is a serious problem in today's scenario since arsenic is associated with several kinds of health problems, such arsenic associated health anomalies are commonly called as 'Arsenism'. Uncontrolled use and spillage of pesticides into the environment has resulted in alarming situation. Moreover serious concerns are being addressed due to their persistence in the environmental matrices such as air, soil and surface water runoff resulting in continuous exposure of these harmful chemicals to human beings and animals. Bio-availability of these environmental toxicants has been enhanced much due to anthropological activities. Dreadfully very few studies are available on combined exposures to these toxicants on the animal or human system. Studies on the acute and chronic exposure to arsenic and DDVP are well reported and well defined. Arsenic is a common global ground water contaminant while dichlorvos is one of the most commonly and widely employed organophosphate based insecticide used in agriculture, horticulture etc. There is thus a real situation where a human may get exposed to these toxicants while working in a field. This review highlights the individual and combined exposure to arsenic and dichlorvos on health.

  17. 空气污染与恶性肿瘤住院人数的关联性分析%Association Between Air Pollution and Hospitalization due to Malignant Neoplasms

    Institute of Scientific and Technical Information of China (English)

    郑山; 刘兴荣; 程宁; 代敏; 李海燕; 李娟生; 康峰; 王敏珍; 任晓卫

    2016-01-01

    [目的]探讨空气污染与人群恶性肿瘤住院人数的关联性. [方法]收集甘肃省金昌市2007-2010年大气污染(PM1o、SO2和NO2)及气象观测数据,以及同期金昌队列人群全部恶性肿瘤住院病例.采用半参数广义相加模型在调整混杂因素后分析大气污染物浓度与该队列人群恶性肿瘤住院人数的关联性. [结果]共收集金昌队列人群恶性肿瘤住院病例2707例.当天(L0)的SO2及平均累积滞后4天(L04)的NO2与恶性肿瘤住院人数的RR值最大,分别为1.043(1.002~1.085)及1.163(1.091~1.239),PM1o及NO2对男性及60岁以上人群的恶性肿瘤住院人数的RR值较女性和60岁及以下人群大.多因素污染物模型中,SO2及NO2对PM10的影响具有协同效应,NO2表现出显著且独立的健康效应.[结论]空气污染与金昌队列人群恶性肿瘤患病住院人数之间具有一定的关联性.%[Objective] To assess the association between air pollution and malignant neoplasms hospital admissions.[Methods] Records of meteorological factors and air pollutants (PM10,SO2,and NO2) were collected in Jinchang City,Gansu Province from 2007 to 2010.The hospitalized cases of malignant neoplasms during the same period were collected from the Jinchang cohort.A semi-parametric generalized additive model was used to assess the relationship between air pollutant concentrations and daily malignant neoplasms hospitalizations in the cohort with adjustment of confounding factors.[Results] A total of 2707malignant neoplasms hospitalized cases were collected.Greater estimates were found for SO2 on Lag 0 day (L0) and for NO2 on Lag04 day (L04),with relative risks (RRs) (95% confidence interval) of 1.043 (1.002-1.085) and 1.163 (1.091-1.239),respectively.The males and the cases at and over 60 years of age were associated more strongly with PM10 and NO2.The multiple-pollutant models showed that SO2 and NO2 were synergic to PM10,and NO2 had a significant and independent health

  18. Evaluation of a portable air purifier.

    OpenAIRE

    Lawrence, J.C.; Lilly, H. A.; Wilkins, M. D.

    1981-01-01

    A portable air purifier significantly reduced mal odour in a small room. If the atmosphere was deliberately contaminated with Serratia marcescens the unit rapidly removed this organism. However, if incorrectly sited, the purifier could disperse organisms into the atmosphere.

  19. Plasma Air Decontamination System (PADS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed Plasma Air Decontamination System (PADS) is a trace contaminant control device based on non-thermal atmospheric-pressure plasma technology. Compared to...

  20. Plasma Air Decontamination System (PADS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed Plasma Air Decontamination System (PADS) is a trace contaminant control device based on non-thermal atmospheric pressure plasma technology that operates...

  1. Variable pattern contamination control under positive pressure

    Energy Technology Data Exchange (ETDEWEB)

    Philippi, H.M. [Chalk River Labs., Ontario (Canada)

    1997-08-01

    Airborne contamination control in nuclear and biological laboratories is traditionally achieved by directing the space ventilation air at subatmospheric pressures in one fixed flow pattern. However, biological and nuclear contamination flow control in the new Biological Research Facility, to be commissioned at the Chalk River Laboratories in 1996, will have the flexibility to institute a number of contamination control patterns, all achieved at positive (above atmospheric) pressures. This flexibility feature, made possible by means of a digitally controlled ventilation system, changes the facility ventilation system from being a relatively rigid building service operated by plant personnel into a flexible building service which can be operated by the facility research personnel. This paper focuses on and describes the application of these unique contamination control features in the design of the new Biological Research Facility. 3 refs., 7 figs.

  2. Hollow Fiber Membrane Dehumidification Device for Air Conditioning System.

    Science.gov (United States)

    Zhao, Baiwang; Peng, Na; Liang, Canzeng; Yong, Wai Fen; Chung, Tai-Shung

    2015-11-16

    In order to provide a comfortable living and working environment indoors in tropical countries, the outdoor air often needs to be cooled and dehumidified before it enters the rooms. Membrane separation is an emerging technology for air dehumidification and it is based on the solution diffusion mechanism. Water molecules are preferentially permeating through the membranes due to its smaller kinetic diameter and higher condensability than the other gases. Compared to other dehumidification technologies such as direct cooling or desiccation, there is no phase transition involved in membrane dehumidification, neither the contact between the fresh air stream and the desiccants. Hence, membrane dehumidification would not only require less energy consumption but also avoid cross-contamination problems. A pilot scale air dehumidification system is built in this study which comprises nine pieces of one-inch PAN/PDMS hollow fiber membrane modules. A 150 h long-term test shows that the membrane modules has good water vapor transport properties by using a low vacuum force of only 0.78 bar absolute pressure at the lumen side. The water vapor concentration of the feed humid air decreases dramatically from a range of 18-22 g/m³ to a range of 13.5-18.3 g/m³. Most importantly, the total energy saving is up to 26.2% compared with the conventional air conditioning process.

  3. Hollow Fiber Membrane Dehumidification Device for Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Baiwang Zhao

    2015-11-01

    Full Text Available In order to provide a comfortable living and working environment indoors in tropical countries, the outdoor air often needs to be cooled and dehumidified before it enters the rooms. Membrane separation is an emerging technology for air dehumidification and it is based on the solution diffusion mechanism. Water molecules are preferentially permeating through the membranes due to its smaller kinetic diameter and higher condensability than the other gases. Compared to other dehumidification technologies such as direct cooling or desiccation, there is no phase transition involved in membrane dehumidification, neither the contact between the fresh air stream and the desiccants. Hence, membrane dehumidification would not only require less energy consumption but also avoid cross-contamination problems. A pilot scale air dehumidification system is built in this study which comprises nine pieces of one-inch PAN/PDMS hollow fiber membrane modules. A 150 h long-term test shows that the membrane modules has good water vapor transport properties by using a low vacuum force of only 0.78 bar absolute pressure at the lumen side. The water vapor concentration of the feed humid air decreases dramatically from a range of 18–22 g/m3 to a range of 13.5–18.3 g/m3. Most importantly, the total energy saving is up to 26.2% compared with the conventional air conditioning process.

  4. Alterações na temperatura do ar mediante telas nas laterais de ambientes protegidos cultivados com tomateiro Changes in air temperature due to side screens of greenhouses cultivated with tomato

    Directory of Open Access Journals (Sweden)

    Larissa A Duarte

    2011-02-01

    Full Text Available Este trabalho avaliou a influência do uso de telas anti-insetos nas laterais de ambientes protegidos sobre a temperatura do ar de um cultivo de tomate. O experimento foi realizado em Itajaí, SC (27º 34' S; 48º 30' W, no período de 17/03 a 25/07/2003, onde foram instalados quatro ambientes cobertos com filme plástico de PEBD, sendo que um deles não possuía revestimento lateral e três estavam revestidos lateralmente, cada um com um tipo de tela anti-insetos. As telas anti-insetos utilizadas foram: clarite (5 fios por cm, citros (10 fios por cm e antiafídeo (20 fios por cm. O ambiente revestido com tela antiafídeo nas laterais apresentou maiores valores de temperatura máxima do ar durante o outono-inverno, o que ocasionou aumento médio de 2,0 °C na temperatura média diária, quando comparado com o ambiente sem tela nas laterais. A variação da temperatura do ar nos ambientes com tela citros e clarite foi semelhante, apresentando ganho térmico diário de 0,4 °C em relação ao ambiente sem tela anti-insetos e possibilitou condições mais estáveis entre as temperaturas noturna e diurna para o cultivo do tomateiro nessa época do ano.This study aims to assess the influence of insect-proof screens installed in plastic greenhouses cultivated with tomato on the air temperature and crop yield. The experiment was conducted in Itajaí, SC, Brazil (27º 34' S; 48º 30' W, from 17/03 to 25/07/2003. Four greenhouses cultivated with tomato and all covered with polyethylene of low density (PEBD in the superior part were used. Three of these environments were covered laterally, each one with a different kind of screen: clarite insect-proof screens (12 meshes per cm, citros insect-proof screens (25 meshes per cm and afideo insect-proof screens (50 meshes per cm. The fourth environment did not receive any side coverage. The covered environment with afideo insect-proof screens on sides presented the highest maximum air temperatures during the

  5. Center for Contaminated Sediments

    Data.gov (United States)

    Federal Laboratory Consortium — The U.S. Army Corps of Engineers Center for Contaminated Sediments serves as a clearinghouse for technology and expertise concerned with contaminated sediments. The...

  6. Contaminated Sites in Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Sites contaminated by hazardous materials or wastes. These sites are those administered by the Contaminated Sites Section of Iowa DNR. Many are sites which are...

  7. Monitoring of surface and airborne contamination

    Energy Technology Data Exchange (ETDEWEB)

    Pradeep Kumar, K.S. [Bhabha Atomic Research Centre, Bombay (India)

    1997-06-01

    Indian nuclear energy programme aims at total safety in all activities involved in the entire fuel cycle for the occupational workers, members of the public and the environment as a whole. Routine radiation monitoring with clearly laid out procedures are followed for ensuring the safety of workers and public. Radiation monitoring carried out for the nuclear installations comprises of process monitoring, monitoring of effluent releases and also of the radiation protection monitoring of the individuals, work place and environment. Regulations like banning of smoking and consumption of food and drink etc. reduces the risk of direct ingestion even if inadvertent spread of contamination takes place. Though limit of transportable surface contamination is prescribed, the health physicists always follow a ``clean on swipe`` philosophy which compensates any error in the measurement of surface contamination. In this paper, the following items are contained: Necessity of contamination monitoring, accuracy required in the calibration of surface contamination monitors, methodology for contamination monitoring, air monitoring, guidelines for unrestricted release of scrap materials, and problems in contamination monitoring. (G.K.)

  8. Can pine needles indicate trends in the air pollution levels at remote sites?

    Energy Technology Data Exchange (ETDEWEB)

    Klanova, Jana, E-mail: klanova@recetox.muni.c [Research Centre for Environmental Chemistry and Ecotoxicology RECETOX, Masaryk University, Kamenice 126/3, 625 00 Brno (Czech Republic); Cupr, Pavel; Barakova, Daniela; Seda, Zdenek; Andel, Petr; Holoubek, Ivan [Research Centre for Environmental Chemistry and Ecotoxicology RECETOX, Masaryk University, Kamenice 126/3, 625 00 Brno (Czech Republic)

    2009-12-15

    Data from ten years of integrated monitoring were used here to evaluate whether pine needles are a feasible tool for an assessment of long-term trends of the atmospheric contamination. Pine needles collected once a year were compared to high volume air samples collected for 24 h, every 7 days, and passive air samples integrated over 28-day periods. Results showed the same concentration patterns of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) captured in needles and high volume samples. Passive air samplers were less efficient in sampling the particle-bound compounds. Theoretical air volume equivalent to each needle sample (V{sub EQ}) was calculated as a ratio of the needle concentration over the mean air concentration. Results indicated different equivalent volumes for PAHs and organochlorines, possibly due to the faster degradation rates of PAHs in needles. The most important finding is that in the long term a needle monitoring gives very similar information on temporal trends of the atmospheric pollution as does a high volume air monitoring. - Pine needle monitoring is a feasible tool for an assessment of temporal trends in the atmospheric contamination.

  9. Time dependent FTIR spectra of mineral waters after contact with air

    CERN Document Server

    Kondyurin, Alexey

    2010-01-01

    FTIR spectra of mineral waters of Slavyanovskaya, Aqua Montana, Bad Harzburger and Christinen with time from first contact of water with open air were analysed. The kinetic of spectral changes of Slavyanovskaya mineral water in the regions of stretch, deformation and intermolecular vibrations was measured. The spectral changes do not correlate with chemical contamination of mineral water and degassing process. The observed spectral changes could be due to different structure of mineral water in liquid state, which is destroyed after air contact. The observed spectral behaviour of Slavyanovskaya is correlated with the catalytic activity of mineral water, which was saved without contact with air. The characteristic time of spectral dependence (669 seconds) is close to the characteristic time of catalytic activity loss (600 seconds) of mineral water at air contact. The spectra results support the medical studies that show the activity of mineral water near spring, and the loosing activity of water after long tim...

  10. Detection and mapping of oil-contaminated soils by remote sensing of laser-induced fluorescence

    Science.gov (United States)

    Luedeker, Wilhelm; Guenther, Kurt P.; Dahn, Hans-Guenter

    1995-10-01

    The contamination of soil by aromatic mineral hydrocarbons (MHC) (e.g., gasoline, oil, etc.) has become a severe environmental problem because not only men, animals, and plants are threatened but also the water and air. With the unification of Germany a great number of suspected contaminated sites in the new countries were registered. An estimation of the German Federal Ministry of Environment (BMU) counts 180,000 areas contaminated with different pollutants, 55,000 are situated in the former GDR. On military settlements for example more than fifty percent of the chemicals are MHCs. Hence one can get an idea of the importance of soil pollution by hydrocarbons. Other zones contaminated due to carelessness or accidents are civil petrolstations, airports, refineries, pipelines, and traffic disasters. At the present time for most of these areas the contamination is assumed due to recent use. Due to the large extension of the problem an estimation and evaluation of the potential hazard for the environment is difficult and expensive to perform. In the case of an actual endangering the total area must be mapped in detail resulting in increasing costs for the owner. Nevertheless it is necessary to find reliable timesaving areal mapping and monitoring methods. One opportunity presented in this paper is the application of remote sensing by laser induced fluorescence from an airborne platform. It promises to fulfill these requirements in a sufficiently fast manner with very high spatial resolution. The access to the pollutant detection is the specific laser induced fluorescence emitted by the MHC (finger print). The present work shows the requirements for a helicopterborne lidar system for MHC mapping and how the detected signals are to be evaluated and interpreted.

  11. Effects of ultraviolet and protons radiations on thermal control coatings after contamination

    Science.gov (United States)

    Faye, D.; Marco, J.

    2003-09-01

    The impact of molecular deposits from spacecraft materials outgassing is not only dependent on sensitive surface nature and contaminant type but also on space environment parameters. In order to study the combined effects of contamination and solar radiation, ground tests have been performed on thermal control coatings: innovative ones such as Flexible and Rigid Solar Reflectors (FSR and RSR), and classic ones such as Optical Solar Reflectors (OSR) and Second Surface Mirrors (SSM). During a first phase, samples of these cold coatings have been exposed to an outgassing flux of different widely used materials: - a PU1 black paint, - a conformal coating MAPSIL 213B, - a structural adhesive Scotchweld EC2216 and to an outgassing flux coming from the mixture of these three materials. During a second phase, the samples have been exposed through two successive tests (either under UV or protons) to a simulated space environment corresponding to one year satellite GEO orbit on North / South faces. Material degradation has been evaluated by in-situ reflectance spectra in the range 250-2500 nm (UV test) and in the range 250-840 nm (Protons test). Negligible changes occurred during initial air to vacuum transition whereas significant recoveries of degradations occurred when returning to ambient atmospheric pressure. The observed degradation is the most important in the UV-visible range independently of the contaminants and substrates. It is partly due to contaminants and substrates for silicone cold coatings FSRs, RSRs, mainly due to contaminants for OSRs, SSMs and mainly due to substrates in the case of paints.

  12. How historical copper contamination affects soil structure and mobilization and transport of colloids

    DEFF Research Database (Denmark)

    Paradelo, Marcos; Møldrup, Per; Holmstrup, Martin;

    between 0.01 to 0.43 pore volumes, with longer times for the most contaminated point, likely related with its higher soil density and lower air permeability. The copper pollution affected colloid and tracer transport in the soil columns. The release of colloids especially in the most contaminated points......Copper is accumulated in soils due to human activities such as mining industry, agriculture practises, or waste deposals. High concentrations of copper can affect plants and soil organisms, and subsequently the soil structure and its inner space architecture. In this work we investigated the effect...... of copper concentration on the movement of an inert tracer, tritium, and the mobilization and transport of colloid particles in undisturbed soil cores (10 cm diameter and 8 cm height). The cores were sampled along a copper gradient of 21 to 3837 mg Cu kg-1 soil on an abandoned arable soil polluted by copper...

  13. Activated Natural Zeolites on Textiles: Protection from Radioactive Contamination

    Science.gov (United States)

    Grancaric, A. M.; Prlic, I.; Tarbuk, A.; Marovic, G.

    Clothing designed to protect against radioactive contamination was based on a simple principle. It was important not to inhale contaminated dust and air and to ensure that contaminated particles could not reach the skin. Therefore, the density of the textile was crucial. New developments, keeping in mind that textile should be lightweight, are focused on textiles which can chemically bind the contamination particles and not allow them either to diffuse to the skin or spread back into the environment. A great success would be if the clothing were made reusable (e.g., for use in the space station). Therefore, new methods (or chemical preparations) are being proposed for developing intelligent textiles.

  14. Skin manifestations and comorbidities of chronic arsenicosis due to contaminated drinking water and their risk factors%慢性饮水型砷中毒患者皮肤表现和合并疾病及影响因素分析

    Institute of Scientific and Technical Information of China (English)

    韩建文; 狄震; 张巧丽; 刘佳; 乌日嘎; 智艳平; 乌日娜

    2016-01-01

    目的:分析慢性饮水型砷中毒患者的皮肤表现、合并疾病以及可能的影响因素。方法对内蒙古95例慢性饮水型砷中毒患者的人口学特征、皮肤表现、合并疾病进行流行病学调查和分析。建立logistic回归模型,分析性别、年龄、开始饮用高砷水年龄、水砷浓度及饮用高砷水时间年龄与皮肤表现、合并疾病间的相关性。结果95例患者中共有77例患者发生色素沉着,75例发生色素减退,93例发生掌跖部皮肤角化,27例患者发生皮肤癌,其中多发性皮肤癌8例。合并结核5例、高血压15例、类风湿性关节炎2例、脑梗死4例、冠心病7例、内脏恶性肿瘤3例、肝硬化6例、贫血2例。回归分析发现色素沉着与水砷浓度相关(OR=0.32,95%CI=0.10~0.98);校正OR=0.27,95%CI=0.08~0.90)。冠心病的发生与饮用高砷水时间具有相关性(OR=6.41,95%CI=1.09~37.88;校正OR=8.55,95%CI=1.212~60.41)。肝硬化的发生与水砷浓度具有相关性(OR=24.67,95%CI=2.69~226.57;校正OR=22.51,95%CI=2.38~213.11)。结论慢性砷中毒患者色素代谢异常、掌跖部皮肤角化、皮肤癌发生率高。水砷浓度、饮用高砷水时间不同对人体可能产生不同的影响。%Objective To investigate skin manifestations and comorbidities of chronic arsenicosis due to conta⁃minated drinking water, and to explore their possible risk factors. Methods Data about demographic characteristics, skin manifestations and comorbidities were collected from 95 patients with chronic arsenicosis due to contaminated drinking water in Inner Mongolia, and retrospectively analyzed. A logistic regression model was established to analyze associations of skin manifestations and comorbidities with patients′ gender, age, age at onset of drinking of arsenic⁃contaminated water, arsenic concentrations in water and duration of arsenic exposure. Results Among the 95 patients, 77 had

  15. New Developments in Contaminant Remediation by Smoldering Combustion

    Science.gov (United States)

    Gerhard, J.; Torero, J. L.; Major, D.; Grant, G.; Scholes, G.; Pironi, P.; Hasan, T.; Salman, M.

    2012-12-01

    In 2006 a new concept for the remediation of soils contaminated with non-aqueous phase liquids (NAPLs) was introduced (Gerhard et al., 2006, AGU Fall Meeting, H24A-01 INVITED). Proof of concept experiments had demonstrated that organic liquids, such as coal tar, could be destroyed via self-sustaining smoldering. Smoldering is an exothermic oxidation reaction in which organic material is converted primarily to energy, water, and carbon dioxide. Unlike flaming combustion, it is a surface reaction and the process is self-sustaining because the process provides (and the system retains) sufficient energy to propagate itself following a one-time, local ignition event (charcoal smoldering in a barbeque is a common example). The technique is promising for the effective destruction of NAPL-contaminated soil in a manner that is cost effective, low energy, and rapid. This presentation will provide an overview of the active and diverse research program underway since the initial proof of concept. More than 80 column experiments have revealed how the rate of destruction can be controlled by the air flux provided and the sensitivity to key parameters including mean grain size, NAPL type, NAPL saturation, and water content. Studies on field soils received from more than 12 sites on 4 continents revealed that the process was robust across a wide range of soils, contaminants and contaminant concentrations. Two-dimensional experiments have revealed the differences between vertical and lateral propagation of a smoldering front and these results have been employed to provide confidence in a numerical model of the process that accounts for heterogeneity of soil properties. Pilot tests undertaken for the in situ treatment of coal tar below the water table at a former chemical manufacturing facility demonstrated self-sustaining NAPL destruction rates of more than 800 kg/day and propagation rates of more than 1.5 m/day. Pilot testing is also underway with an ex situ reactor for the

  16. Contaminants in ventilated filling boxes

    Science.gov (United States)

    Bolster, D. T.; Linden, P. F.

    While energy efficiency is important, the adoption of energy-efficient ventilation systems still requires the provision of acceptable indoor air quality. Many low-energy systems, such as displacement or natural ventilation, rely on temperature stratification within the interior environment, always extracting the warmest air from the top of the room. Understanding buoyancy-driven convection in a confined ventilated space is key to understanding the flow that develops with many of these modern low-energy ventilation schemes. In this work we study the transport of an initially uniformly distributed passive contaminant in a displacement-ventilated space. Representing a heat source as an ideal sourced of buoyancy, analytical and numerical models are developed that allow us to compare the average efficiency of contaminant removal between traditional mixing and modern low-energy systems. A set of small-scale analogue laboratory experiments was also conducted to further validate our analytical and numerical solutions.We find that on average traditional and low-energy ventilation methods are similar with regard to pollutant flushing efficiency. This is because the concentration being extracted from the system at any given time is approximately the same for both systems. However, very different vertical concentration gradients exist. For the low-energy system, a peak in contaminant concentration occurs at the temperature interface that is established within the space. This interface is typically designed to sit at some intermediate height in the space. Since this peak does not coincide with the extraction point, displacement ventilation does not offer the same benefits for pollutant flushing as it does for buoyancy removal.

  17. Contamination by trace elements at e-waste recycling sites in Bangalore, India.

    Science.gov (United States)

    Ha, Nguyen Ngoc; Agusa, Tetsuro; Ramu, Karri; Tu, Nguyen Phuc Cam; Murata, Satoko; Bulbule, Keshav A; Parthasaraty, Peethmbaram; Takahashi, Shin; Subramanian, Annamalai; Tanabe, Shinsuke

    2009-06-01

    The recycling and disposal of electronic waste (e-waste) in developing countries is causing an increasing concern due to its effects on the environment and associated human health risks. To understand the contamination status, we measured trace elements (TEs) in soil, air dust, and human hair collected from e-waste recycling sites (a recycling facility and backyard recycling units) and the reference sites in Bangalore and Chennai in India. Concentrations of Cu, Zn, Ag, Cd, In, Sn, Sb, Hg, Pb, and Bi were higher in soil from e-waste recycling sites compared to reference sites. For Cu, Sb, Hg, and Pb in some soils from e-waste sites, the levels exceeded screening values proposed by US Environmental Protection Agency (EPA). Concentrations of Cr, Mn, Co, Cu, In, Sn, Sb, Tl, Pb and Bi in air from the e-waste recycling facility were relatively higher than the levels in Chennai city. High levels of Cu, Mo, Ag, Cd, In, Sb, Tl, and Pb were observed in hair of male workers from e-waste recycling sites. Our results suggest that e-waste recycling and its disposal may lead to the environmental and human contamination by some TEs. To our knowledge, this is the first study on TE contamination at e-waste recycling sites in Bangalore, India.

  18. Hospital-acquired infections associated with poor air quality in air-conditioned environments

    OpenAIRE

    Daniela Pinheiro da Silva

    2014-01-01

    Backgound and Objectives: Individuals living in cities increasingly spend more time indoors in air-conditioned environments. Air conditioner contamination can be caused by the presence of aerosols from the external or internal environment, which may be associated with disease manifestations in patients present in this type of environment. Therefore, the aim of this review was to assess the air quality in air-conditioned hospital environments as a risk factor for hospital-acqui...

  19. Contamination monitoring and control on ASML MS-VII 157-nm exposure tool

    Science.gov (United States)

    Okoroanyanwu, Uzodinma; Gronheid, Roel; Coenen, Jan; Hermans, Jan; Ronse, Kurt G.

    2004-05-01

    This paper presents results of monitoring and control of contaminants in an ASML MS-VII 157nm full-field exposure tool at IMEC, as verified lithographically in terms of field uniformity, lens transmission, CD uniformity, and scattered light. The daily contamination monitoring system utilizes in-line photo-ionization detector, oxygen and moisture analyzers, as well as chemiluminescent detector, and gas chromatograph that is coupled to a mass spectrometer. On a monthly basis, contamination monitoring was performed with thermal desorption-gas chromatographi/mass spectrometric techniques. The following four locations within the optical path of the MS-VII are monitored: source optic assembly, condenser lens optic, 1X relay station, and projection optics box. Contamination control is realized in the system with an on-board purge control unit, which is equipped with gas purifiers that remove contaminants such as H2O, O2, CO, CO2, hydrocarbons, H2, and sulfur compounds. All the observed contaminants have been trending within expected values and no contamination-related tool performance degradation has been observed. The excursions observed in the contaminant concentrations are coincident with tool downtime/maintenance events. Siloxane levels appear to be consistently below 50 ppt in all the monitored locations within the optical path of the tool, except on one occasion when it reached 90 ppt in the projection optics. Volatile organic compounds (VOCs) concentration within the MS-VII enclosure show a stable background level of around 10-25 ppb during weekends and levels of 45-60 ppb (during working days). VOCs concentration variations inside the MS-VII enclosure during the working days correlate well with activities inside the clean room. Air recirculation and low intake of fresh air inside the MS-VII tend to slow down the speed with which the VOCs levels decreases to stable background level, whenever there was a major upward excursion in their concentration. Average light

  20. Induced Contamination Predictions for JAXA's MPAC&SEED Devices

    Science.gov (United States)

    Steagall, Courtney; Smith, Kendall; Huang, Alvin; Soares, Carlos; Mikatarian, Ron

    2008-01-01

    Externally mounted ISS payloads are exposed to the induced ISS environment, including material outgassing and thruster plume contamination. The Boeing Space Environments Team developed analytical and semiempirical models to predict material outgassing and thruster plume induced contamination. JAXA s SM/MPAC&SEED experiment provides an unique opportunity to compare induced contamination predications with measurements. Analysis results are qualitatively consistent with XPS measurements. Calculated depth of contamination within a factor of 2-3 of measured contamination. Represents extremely good agreement, especially considering long duration of experiment and number of outgassing sources. Despite XPS limitations in quantifying plume contamination, the measured and predicted results are of similar scale for the wake-facing surfaces. JAXA s JEM/MPAC&SEED experiment will also be exposed to induced contamination due to JEM and ISS hardware. Predicted material outgassing induced contamination to JEM/MPAC&SEED ranges from 44 to 262 (depending on surface temperature) for a 3 year exposure duration.

  1. Réduction de la pollution atmosphérique due à l'automobile et économie d'énergie Reducing Air Pollution Caused by Automobiles and Energy Conservations

    Directory of Open Access Journals (Sweden)

    Salé B.

    2006-11-01

    Full Text Available L'action engagée dans les pays industriels pour réduire la pollution atmosphérique doit maintenant tenir compte, plus encore que par le passé, de la nécessité, imposée par la conjoncture, d'économiser l'énergie. L'article est consacré à l'étude de la compatibilité de ces deux objectifs en ce qui concerne l'automobile. L'ensemble des actions antigaspillage ou antipollution ne portant pas sur le générateur d'énergie constitue un domaine de compatibilité évident. En revanche la réduction des émissions de polluants nécessite des modifications plus ou moins profondes du moteur dont certaines peuvent poser des problèmes du point de vue de l'économie d'énergie. Dans le but de préciser la nature de ces problèmes, les techniques antipollution correspondant à différents niveaux de limitation des émissions sont examinées du point de vue de leur coût, de leur incidence sur la consommation de carburant et de leur interaction avec les procédés visant à l'économie d'énergie. Sont ainsi passés en revue les moyens de réduction des émissions basés sur une amélioration de la combustion, les procédés de post-combustion, le problème de la réduction de la teneur en plomb des essences. Cette analyse montre que dans une large mesure la réduction des émissions de polluants et la diminution de la consommation sont des objectifs compatibles, mais que la difficulté des problèmes à résoudre pour que les mesures antipollution n'aient pas d'effet négatif au plan de l'économie d'énergie croît très rapidement avec la sévérité de ces mesures au-delà d'un certain niveau. L'effort de recherche entrepris dans le monde sur ce thème devrait progressivement permettre à la fois de réduire encore de façon substantielle les émissions de polluants et d'améliorer le rendement des moteurs. Efforts made by industrialized countries ta reduce air pollution must now, more than ever, give consideration to the need for energy

  2. Pre-Feasibility Analysis of Pellet Manufacturing on the Former Loring Air Force Base Site. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Hunsberger, R.; Mosey, G.

    2014-04-01

    The U.S. Environmental Protection Agency (EPA) Office of Solid Waste and Emergency Response, in accordance with the RE-Powering America's Lands initiative, engaged the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to conduct feasibility studies to assess the viability of developing renewable energy generating facilities on contaminated sites. This site, in Limestone, Maine -- formerly the location of the Loring Air Force Base but now owned by the Aroostook Band of Micmac -- was selected for the potential to produce heating pellets from woody feedstock. Biomass was chosen as the renewable energy resource to evaluate based on abundant woody-biomass resources available in the area. NREL also evaluates potential savings from converting existing Micmac property from oil-fired heating to pellet heating.

  3. FINAL REPORT: MEMBRANE-MEDIATED EXTRACTION AND BIODEGRADATION OF VOLATILE ORGANIC COMPOUNDS FROM AIR

    Science.gov (United States)

    The report describes feasibility tests of a two-step strategy for air pollution control applicable to exhaust air contaminated with volatile organic compounds (VOCs) from painting aircraft. In the first step, the VOC-contaminated air passes over coated, polypropylene, hollow-fibe...

  4. On the fundamentals of thermal treatment for the cleanup of contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Lighty, J.S.; Silcox, G.D.; Pershing, D.W. (Utah Univ., Salt Lake City, UT (USA)); Cundy, V.A. (Louisiana State Univ., Baton Rouge, LA (USA))

    1988-01-01

    Considerable research has focused on air emissions from the afterburner, mainly as a result of the regulations regarding destruction and removal efficiency of a principle organic hazardous constituent (POHC) -99.99% of the POHC must be destroyed in the system based on gas measurements from the afterburner. Research focusing on the primary desorber environment, the evolution of contaminants from solids and the resulting quality of the ash, is limited. The primary desorber is often operated at high temperatures which is costly, particularly for the cleanup of contaminated solid, due to high auxiliary fuel requirements. A more desirable option would be to desorb the contaminants from the soil at lower temperatures and then expose the off-gas to a high-temperature afterburner for decomposition of the hazardous compounds. In addition, the ability to predict the quality of the resulting soil is desirable for delisting purposes. To understand the desorption process, research must explore the rate controlling processes that are occurring. The overall goal of this research is to develop an understanding of the fundamental transport phenomena associated with the evolution of hazardous materials from soils in the primary desorber environment. As well, the rate information obtained can be used to model the thermal desorption of contaminants under a variety of experimental conditions; from these results large-scale operating parameters can be determined for optimum cleanup conditions.

  5. Kentucky Department for Natural Resources and Environmental Protection permit application for air contaminant source: SRC-I demonstration plant, Newman, Kentucky. Appendix D. Impact assessment. [Demonstration plant at Newman, KY

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-11-21

    In appendix D, the air quality condition for various pollutants in the areas surrounding the proposed demonstration plant site is given with respect to attainment or non-attainment of US EPA regulations. The minimum pollutant emission rates for these regulated and for several other pollutants are given. Then the estimated emission rates from the proposed plant are given for a dozen pollutants which exceed these limits and therefore require an ambient air quality analysis. This involves taking into account the estimated emission of these pollutants from the proposed plant and from other sources in the surrounding area. Finally, background data from the surrounding area including meteorological data and sampling of regulated pollutants are given. (LTN)

  6. Detection, simulation, assessing environmental influences. Climate/shock/irradiation/vibrations/electromagnetism/air contamination/biological influences. Papers. Umwelteinfluesse erfassen, simulieren, bewerten. Klima/Schock/Strahlung/Vibrationen/Elektromagnetismus/Luftverunreinigung/Biologische Einfluesse. Vortraege

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    Investigations using environmental simulation are designed to reveal cause-and-effect mechanisms in ageing and weathering processes. Issues of artificial ageing and timelapsing play an important role. The 29 contributions to the 21st Annual Conference deal in particular with the topics: strategies in environmental simulation, irradiation and exposure testing of polymers, atmospheric influences and air ingredients, and mechanical environmental influences. (orig./DG)

  7. Study of plutonium and americium contamination in agricultural area, radiological impact caused by consumption of vegetables of this area; Estudio de la contaminacion de plutonio y americio en un area agricola, impacto radiologico ocasionado por consumo de vegetales contaminados

    Energy Technology Data Exchange (ETDEWEB)

    Espinosa, Assuncion; Aragon, Antonio; Cruz, Berta de la; Gutierrez, Jose [Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, Madrid (Spain). Dept. de Impacto Ambiental de la Energia

    2001-07-01

    The transuranide concentration has been studied for 30 years in vegetable production, crops in wide extensions and in private-owned farms, all of them situated within the Pu-contaminated area of Palomares due to an air accident in 1966. Based on these studies, a preliminary estimation of the radiological risk caused by the consumption of these products by the inhabitants was possible. The results show that most of the fruits present a surface contamination, which disappears or is significantly reduced when they are washed. The contamination present in edible parts of the vegetables, as well as the contamination of other products included in the diet, has facilitated the estimation of the effective dose for ingestion and the committed effective dose for 50 years for the inhabitants. The main conclusions are: those plants, whose cultivation period is less than a year, present a low level of contamination; the green parts of the plants have a higher contamination than the fruits; the Pu soil to plant transfer factor is very low. In general, those plants that have remained in the contaminated land for several years present a high contamination level; the ingestion of products from Palomares does not represent an important risk for the population, even in the case that the products were totally consumed by a critical group.( author)

  8. Air Cleaning Devices for HVAC Supply Systems in Schools. Technical Bulletin.

    Science.gov (United States)

    Wheeler, Arthur E.

    Guidelines for maintaining indoor air quality in schools with HVAC air cleaning systems are provided in this document. Information is offered on the importance of air cleaning, sources of air contaminants and indoor pollutants, types of air cleaners and particulate filters used in central HVAC systems, vapor and gas removal, and performance…

  9. Survey on microorganism contamination in air of dental clinic in a hospital%某部医院口腔科门诊空气微生物污染状况的调查

    Institute of Scientific and Technical Information of China (English)

    曹巧玲; 杨凯; 金世富; 潘朝阳; 王京

    2013-01-01

    目的 了解口腔科门诊空气中的微生物分布,以便更好地指导临床消毒工作,预防医院感染.方法 对某部医院口腔科门诊环境中空气污染细菌与真菌的含量进行检测,选择门诊高峰期后30 min,采用平板沉降法采集口腔科的空气样本,普通营养琼脂平板培养后计数菌落、革兰染色及分离鉴定进行判断分析.结果 口腔科空气中污染微生物以细菌为主,空气中细菌总数符合国家卫生标准.革兰染色结果表明,口腔科门诊室空气中细菌大多数为革兰阳性菌,占细菌总数的83.26%.口腔科门诊空气中的真菌含量较多.其中牙周科含菌量最高,达525个/m3空气.致病菌分离出3株葡萄球菌和2株乙型溶血性链菌.结论 口腔科门诊患者多,流动性大,各种急慢性感染性疾病的患者均在一般患者中间就诊,因此,提示需要进一步加强对口腔科门诊环境的消毒,以控制医院感染的发生及流行.%[Objective]To understand the distribution of microorganisms in air of dental clinic, provide the basis for guiding the clinical disinfection and preventing the nosocomial infection. [ Methods] The contents of bacteria and fungi in air of dental clinic in a hospital were detected. The air samples were collected by the flat sedimentation method at 30 minutes after visiting peak. After the ordinary nutrient agar plate culture, the colony counting, Gram's staining, isolation and identification were performed for analysis. [Results]The main microorganism of air pollution in dental clinic was bacteria, and the total bacteria count in air met the national health standards. The Crams staining showed that the bacteria in air of dental clinic mainly were Gram-positive bacteria, accounting for 83.26% of total bacteria count. The content of fungi in air of dental clinic was high. The content of microorganism in department of periodontology was the highest, which reached 525/m3. 3 strains of Staphylococcus and 2

  10. Uptake of polychlorinated biphenyls and organochlorine pesticides from soil and air into radishes (Raphanus sativus)

    DEFF Research Database (Denmark)

    Mikes, Ondrej; Cupr, P.; Trapp, Stefan

    2009-01-01

    Uptake of organochlorine pesticides and polychlorinated biphenyls from soil and air into radishes was measured at a heavily contaminated field site. The highest contaminant concentrations were found for DDT and its metabolites, and for beta-hexachlorocyclohexane. Bioconcentration factor (BCF...

  11. Fungal colonization of air-conditioning systems

    Directory of Open Access Journals (Sweden)

    Ljaljević-Grbić Milica

    2008-01-01

    Full Text Available Fungi have been implicated as quantitatively the most important bioaerosol component of indoor air associated with contaminated air-conditioning systems. rarely, indoor fungi may cause human infections, but more commonly allergenic responses ranging from pneumonitis to asthma-like symptoms. From all air conditioner filters analyzed, 16 fungal taxa were isolated and identified. Aspergillus fumigatus causes more lethal infections worldwide than any other mold. Air-conditioning filters that adsorb moisture and volatile organics appear to provide suitable substrates for fungal colonization. It is important to stress that fungal colonization of air-conditioning systems should not be ignored, especially in hospital environments.

  12. Microbiological monitoring of air quality in a university canteen: an 11-year report.

    Science.gov (United States)

    Osimani, A; Aquilanti, L; Tavoletti, S; Clementi, F

    2013-06-01

    Over the past decade, an increased tendency to consume meals at dining facilities outside the home has been highlighted; moreover, meals supplied in food businesses have been involved in many foodborne disease outbreaks. Therefore, microbial air contamination in food processing facilities could be a concern and an increase of microbial loads could represent a risk factor, especially for the potential contamination of foods due to undesirable spoiling and pathogenic bacteria. In this paper, the results of an 11-year microbiological monitoring of air quality in a university canteen are reported. The study, which started in the year 2000, was performed within a hazard analysis and critical control point (HACCP) plan implementation of a canteen that produces about 1,000 meals a day in order to verify the effectiveness of corrective actions on the indoor air quality. The primary food preparation room, the kitchen, and three cold rooms underwent air sampling by using a calibrated impaction sampler. Our investigation detected a general and progressive improvement in the air quality of the canteen since the beginning of the study, thus suggesting the appropriateness of the corrective action undertaken during the HACCP implementation program.

  13. Contamination Prediction on Insulators Considering of Meteorology,Geomentric Parameters and Air Pollutant%考虑气象、几何参数、大气污染物的绝缘子表面污秽度预测方法

    Institute of Scientific and Technical Information of China (English)

    王黎明; 刘霆; 黄睿; 梅红伟; 项阳

    2016-01-01

    In order to develop a model to predict the severity of contamination deposition whieh could take account of the effects of the meteorology, geometric parameters of insulators, and air pollutant ,we studied the contamination deposition characteristics of post insulators by means of computanational fluid dynamics.Moreover, we analyzed the chemical composition of salt in pollutant on insulators.The results demonstrate that as the wind speed grows, the contamination on the bottom suface rises and remains about the 80% of the maxmium value, while the contamination on the top sufaces increaces first and then decreases.Moreover, the contamination deposition grows as the relative humidity gets bigger, but it will be less than five times of the value as the relative humidity is 30%.The chemcial composition of the salt contamination on insulators is uniform in the same region.At last, the model is verified with an example, and it is revealed that if the relief effect of rainfall is thought over, the predicted value will be less than four times the samples' mesured value at its worst condition.The proposed new method of contamination prediction can be used for a reference for further researches.%为了提出一种能综合考虑气象、绝缘子几何参数、大气污染物影响的污秽度预测方法,利用计算流体力学的方法对绝缘子的积污特性进行了研究,并对换流站污秽盐分构成进行了分析.研究表明:随风速增加,下表面积污量增加并维持在最大值的80%左右,上表面的积污量先增大后减小;相对湿度增加将使上下表面的积污量均增加,最大值小于同等条件下相对湿度为30%时的5倍.盐分构成分析显示污秽盐分构成具有地区一致性的特点.在利用相关研究成果考虑降雨清洗效应的情况下,结合实例对模型进行了验算,偏差最大的预测值小于实测值的4倍.该新的污秽度预测方法可以为污秽预测的进一步研究提供借鉴.

  14. Environmental remediation through sequestration of airfall-derived metals contamination by selective revegetation strategies

    Science.gov (United States)

    Sahagian, D.; Peters, S.; Yasko, G.

    2006-12-01

    Industrial activities in the 20th century left a legacy of contaminated air, water, and soils. The relative environmental enlightenment of the 21st century has already led to reductions in pollution sources, and has improved air and surface water quality in many areas. However, the residence time of contaminants in soils can be lengthy, presenting a challenge to 21st century restoration of impacted ecosystems and communities. The present study is centered on the Borough of Palmerton, PA, and a broad region of adjacent communities that were affected by two zinc smelters that operated continuously for more than 80 years, emitting thousands of tons of heavy metals including zinc, cadmium, lead and arsenic. While the air quality has vastly improved since the closure of the zinc smelters, the community remains adversely affected by the ecological damage caused by the pollution. The north face of the Kittatiny ridge was completely denuded of vegetation from the high metals concentrations. The region suffers further due to the ongoing perception of contaminated soils and water, leaving the town and surrounding areas economically depressed. In this study, we are examining the impact of revegetation strategies, particularly those using warm season grasses to determine which species survive and indeed thrive in the metals-contaminated soils. Because of the large areal extent and locally steep slopes in the broad area of concern, removal of metals from the entire region is impractical. It is considered more effective to sequester the metals in the soil so that they do not leach into the rivers, or enter the food web. Vegetation that absorbs and transports the metals throughout its tissues would mobilize these pollutants into the food web as well as make the metals available to reach the river via leaves and other vegetative structures. In this study, we are monitoring the uptake of metals by test grasses and other plants that are colonizing the contaminated area, as well as

  15. Application of disability adjusted life years in evaluating health effects due to particulate air pollution in Chinese cities%应用伤残调整寿命年评价我国城市大气颗粒物污染的人群健康效应

    Institute of Scientific and Technical Information of China (English)

    陈仁杰; 陈秉衡; 阚海东

    2010-01-01

    目的 评价大气颗粒物污染引起我国城市居民伤残调整寿命年(disability adjusted life years,DALYs)的损失.方法 以2006年我国656个城市的城市人口作为暴露人口,以国家控制大气质量监测体系中各城市的可吸入颗粒物(particulate matter with an aerodynamic diameter less than 10 microns,PM_(10))年均浓度为暴露水平,应用DALYs指标,评价我国城市大气颗粒物污染的人群健康效应.结果 2006年大气颗粒物污染能引起我国城市居民(50.66±9.52)万例早逝,(15.66±4.12)万例慢性支气管炎患者,(1264.05±522.97)万例内科门诊患者,(9.99±5.04)万例心血管疾病住院患者和(7.20±0.82)万例呼吸系统疾病住院患者.2006年归因于城市大气颗粒物污染的DALYs损失总计为(526.22±99.43)万人年,其中由早逝引起的百分率为96.26%(506.55/526.22).城市颗粒物污染越重,城市人口越多,则相应的DALYs损失越大.结论 大气颗粒物污染已对我国城市居民的健康造成了较大的影响,从公共卫生的角度说明了加强治理大气污染的必要性和迫切性.%Objective To evaluate the loss of disability adjusted life years (DALYs) due to particulate air pollution in Chinese urban residents. Methods DALYs was applied to evaluate the health effects due to particulate air pollution in the residents of 656 Chinese cities, and the data of annual average concentrations of inhalable particle (PM_(10)) in 2006 were collected from the state-owned air quality monitoring network. Results Particulate air pollution in Chinese urban areas in 2006,could canse(506. 6± 95.2) thousand premature deaths, (156.6±41.2) thousand new cases of chronic bronchitis, (12.6±5.2) million outpatient visits for internal medicine, (99. 9±50. 4) thousand and (72. 0 ± 8. 2) thousand hospital admissions for cardiovascular diseases and respiratory diseases respectively. The attributable DALYs loss in urban residents amounted up to (5.26 ± 0.99) million

  16. Evaluation of health factors in high-rise buildings. 2. Bioclimatological consequences resulting from comparative measurements of the air ionisation in a high-rise building located in a heavily contaminated suburban area and at certain altitudes

    Energy Technology Data Exchange (ETDEWEB)

    Moese, J.R.; Fischer, G.

    1981-01-01

    According to accepted scientific theories inhaled small ions deliver their charges in the pulmonary alveoli and this leads to local recharges. This process stimulates structures of the central nervous system and the activity of the endocrine is excited, resulting in an enhancement of the general well-being. These possibilities of interpretation regarding a biological ionic effect are supported, with reservations by positive medical effects during and after a stay in a well-ventilated mountain climate or also in a sea-climate. Owing to their lower mobility the large ions are inhaled as small ions to an increasing extent. The chemical and physical noxa are delivered and deposited in the respiratory tract. They stick the epithelia in the trachea and in the bronchi as well as the endothelia in the lung vesicles. The number of the ciliary movements is reduced. Similar effects are known to be caused also by nicotine abuse. This results in a decreased ability of expectoration and a lower intake of oxygen by the alveoli. These facts could furnish an explanation for the increased vulnerability of city dwellers to infections diseases and to catarrh. The changed ionisation of air in urbanised areas definitely represents only one of the many risk factors. In addition to the attempt to characterize bioclimatically local weather conditions by means of the non-conventional parameter air ionisation our study has also been intended to establish biologically oriented criteria for the living in a high-rise building in a particularly unfavourable location. Under specific microclimatic conditions the uppermost storeys were at times bioclimatically favoured over the lowermost, especially when shallow air inversion is present. In such cases, small ions exclusively were registered in the upper storeys and large ions in the lower floors.

  17. Experimental evaluation of enthalpy efficiency and gas-phase contaminant transfer in an enthalpy recovery unit with polymer membrane foils

    DEFF Research Database (Denmark)

    Nie, Jinzhe; Yang, Jianrong; Fang, Lei;

    2015-01-01

    Experimental studies were conducted in a laboratory setting to investigate the enthalpy efficiency and gas-phase contaminant transfer in a polymer membrane enthalpy recovery unit. One commercially available polymer membrane enthalpy recovery unit was used as a reference unit. Simulated indoor air...... and outdoor air by twin chambers was connected to the unit. Three chemical gases were dosed to the indoor exhaust air to mimic indoor air contaminants. Based on the measurements of temperature, humidity ratio, and contaminant concentrations of the indoor exhaust air and outdoor air supply upstream...... and downstream of the unit, the temperature efficiencies, humidity efficiencies, enthalpy efficiencies, and contaminant transfer ratios were calculated. The results showed that over 60% of enthalpy recovery efficiency could be achieved and that the contaminant transfer ratios were in the range of 5.4% to 9...

  18. Changes in air flow patterns using surfactants and thickeners during air sparging: bench-scale experiments.

    Science.gov (United States)

    Kim, Juyoung; Kim, Heonki; Annable, Michael D

    2015-01-01

    Air injected into an aquifer during air sparging normally flows upward according to the pressure gradients and buoyancy, and the direction of air flow depends on the natural hydrogeologic setting. In this study, a new method for controlling air flow paths in the saturated zone during air sparging processes is presented. Two hydrodynamic parameters, viscosity and surface tension of the aqueous phase in the aquifer, were altered using appropriate water-soluble reagents distributed before initiating air sparging. Increased viscosity retarded the travel velocity of the air front during air sparging by modifying the viscosity ratio. Using a one-dimensional column packed with water-saturated sand, the velocity of air intrusion into the saturated region under a constant pressure gradient was inversely proportional to the viscosity of the aqueous solution. The air flow direction, and thus the air flux distribution was measured using gaseous flux meters placed at the sand surface during air sparging experiments using both two-, and three-dimensional physical models. Air flow was found to be influenced by the presence of an aqueous patch of high viscosity or suppressed surface tension in the aquifer. Air flow was selective through the low-surface tension (46.5 dyn/cm) region, whereas an aqueous patch of high viscosity (2.77 cP) was as an effective air flow barrier. Formation of a low-surface tension region in the target contaminated zone in the aquifer, before the air sparging process is inaugurated, may induce air flow through the target zone maximizing the contaminant removal efficiency of the injected air. In contrast, a region with high viscosity in the air sparging influence zone may minimize air flow through the region prohibiting the region from de-saturating.

  19. Contaminated soil concrete blocks

    NARCIS (Netherlands)

    Korte, de A.C.J.; Brouwers, H.J.H.; Limbachiya, Mukesh C.; Kew, Hsein Y.

    2009-01-01

    According to Dutch law the contaminated soil needs to be remediated or immobilised. The main focus in this article is the design of concrete blocks, containing contaminated soil, that are suitable for large production, financial feasible and meets all technical and environmental requirements. In ord

  20. Air Cleaning Technologies

    Science.gov (United States)

    2005-01-01

    , and personal protection methods. Engineering methods that are usually carried out by the building’s heating, ventilation, and air conditioning (HVAC) system function to prevent the spread of airborne infectious pathogens by diluting (dilution ventilation) and removing (exhaust ventilation) contaminated air from a room, controlling the direction of airflow and the air flow patterns in a building. However, general wear and tear over time may compromise the HVAC system’s effectiveness to maintain adequate indoor air quality. Likewise, economic issues may curtail the completion of necessary renovations to increase its effectiveness. Therefore, when exposure to airborne infectious pathogens is a risk, the use of an in-room air cleaner to reduce the concentration of airborne pathogens and prevent the spread of airborne infectious diseases has been proposed as an alternative to renovating a HVAC system. Airborne transmission is the spread of infectious pathogens over large distances through the air. Infectious pathogens, which may include fungi, bacteria, and viruses, vary in size and can be dispersed into the air in drops of moisture after coughing or sneezing. Small drops of moisture carrying infectious pathogens are called droplet nuclei. Droplet nuclei are about 1 to 5μm in diameter. This small size in part allows them to remain suspended in the air for several hours and be carried by air currents over considerable distances. Large drops of moisture carrying infectious pathogens are called droplets. Droplets being larger than droplet nuclei, travel shorter distances (about 1 metre) before rapidly falling out of the air to the ground. Because droplet nuclei remain airborne for longer periods than do droplets, they are more amenable to engineering infection control methods than are droplets. Droplet nuclei are responsible for the airborne transmission of infectious diseases such as tuberculosis, chicken pox (varicella), measles (rubeola), and dessiminated herpes