WorldWideScience

Sample records for toxic air contaminants

  1. Evaluating the Spatial Distribution of Toxic Air Contaminants in Multiple Ecosystem Indicators in the Sierra Nevada-Southern Cascades

    Science.gov (United States)

    Nanus, L.; Simonich, S. L.; Rocchio, J.; Flanagan, C.

    2013-12-01

    Toxic air contaminants originating from agricultural areas of the Central Valley in California threaten vulnerable sensitive receptors including surface water, vegetation, snow, sediments, fish, and amphibians in the Sierra Nevada-Southern Cascades region. The spatial distribution of toxic air contaminants in different ecosystem indicators depends on variation in atmospheric concentrations and deposition, and variation in air toxics accumulation in ecosystems. The spatial distribution of organic air toxics and mercury at over 330 unique sampling locations and sample types over two decades (1990-2009) in the Sierra Nevada-Southern Cascades region were compiled and maps were developed to further understand spatial patterns and linkages between air toxics deposition and ecological effects. Potential ecosystem impacts in the Sierra Nevada-Southern Cascades region include bioaccumulation of air toxics in both aquatic and terrestrial ecosystems, reproductive disruption, and immune suppression. The most sensitive ecological end points in the region that are affected by bioaccumulation of toxic air contaminants are fish. Mercury was detected in all fish and approximately 6% exceeded human consumption thresholds. Organic air toxics were also detected in fish yielding variable spatial patterns. For amphibians, which are sensitive to pesticide exposure and potential immune suppression, increasing trends in current and historic use pesticides are observed from north to south across the region. In other indicators, such as vegetation, pesticide concentrations in lichen increase with increasing elevation. Current and historic use pesticides and mercury were also observed in snowpack at high elevations in the study area. This study shows spatial patterns in toxic air contaminants, evaluates associated risks to sensitive receptors, and identifies data gaps. Future research on atmospheric modeling and information on sources is needed in order to predict which ecosystems are the

  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. Trace Contaminant Monitor for Air in Spacecraft, Phase I

    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...

  4. Determination of tricresyl phosphate air contamination in aircraft.

    Science.gov (United States)

    Denola, G; Hanhela, P J; Mazurek, W

    2011-08-01

    Monitoring of tricresyl phosphate (TCP) contamination of cockpit air was undertaken in three types of military aircraft [fighter trainer (FT), fighter bomber (FB), and cargo transport (CT) aircraft]. The aircraft had a previous history of pilot complaints about cockpit air contamination suspected to originate from the engine bleed air supply through the entry of aircraft turbine engine oil (ATO) into the engine compressor. Air samples were collected in flight and on the ground during engine runs using sorbent tubes packed with Porapak Q and cellulose filters. A total of 78 air samples were analysed, from 46 different aircraft, and 48 samples were found to be below the limit of detection. Nine incidents of smoke/odour were identified during the study. The concentrations of toxic o-cresyl phosphate isomers were below the level of detection in all samples. The highest total TCP concentration was 51.3 μg m(-3), while most were generally found to be contamination of cabin/cockpit air has been the subject of much concern in aviation, quantitative data are sparse.

  5. National Air Toxic Assessments (NATA) Results

    Data.gov (United States)

    U.S. Environmental Protection Agency — The National Air Toxics Assessment was conducted by EPA in 2002 to assess air toxics emissions in order to identify and prioritize air toxics, emission source types...

  6. Baltimore Air Toxics Study (BATS)

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, D.A. [Sullivan Environmental Consulting, Inc., Alexandria, VA (United States)

    1996-12-31

    The Baltimore Air Toxics Study is one of the three urban air toxics initiatives funded by EPA to support the development of the national air toxics strategy. As part of this project, the Air Quality Integrated Management System (AIMS) is under development. AIMS is designed to bring together the key components of urban air quality management into an integrated system, including emissions assessment, air quality modeling, and air quality monitoring. Urban area source emissions are computed for a wide range of pollutants and source categories, and are joined with existing point source emissions data. Measured air quality data are used to evaluate the adequacy of the emissions data and model treatments as a function of season, meteorological parameters, and daytime/nighttime conditions. Based on tested model performance, AIMS provides the potential to improve the ability to predict air quality benefits of alternative control options for criteria and toxic air pollutants. This paper describes the methods used to develop AIMS, and provides examples from its application in the Baltimore metropolitan area. The use of AIMS in the future to enhance environmental management of major industrial facilities also will be addressed in the paper.

  7. Air contamination analysis during emergency medical treatment

    International Nuclear Information System (INIS)

    Yamada, Y.; Fukutsu, K.; Yuuki, M.; Akashi, M.

    2009-01-01

    After radiological emergencies, patients contaminated with radioactivity are taken to radiation emergency hospitals for treatment. Numerical simulations using the computer software 'Flow Designer R were made in order to evaluate indoor air contamination caused by the breathing out of contaminated air. The National Inst. of Radiological Sciences facility was used for the numerical evaluation. Results indicate that the dispersion of contaminated air depends on the characteristics of the contaminants, and that the dispersion range was limited and localised. Only medical staff standing in a special position near the patient was exposed to almost un-diluted contaminated air. Highly contaminated air was evacuated with a local exhaust pump system. Room air quality was monitored using a continuous air sampling system, but it was found that the sampling point was not representative for the purpose of radiation protection. From the air-flow analysis, some problems that affect radiological safety were revealed and valuable information and measures for preventing secondary contamination were determined. (authors)

  8. Integrated fate and toxicity assessment for site contaminants

    International Nuclear Information System (INIS)

    MacDonell, Margaret; Peterson, John; Finster, Molly; Douglas, R.

    2007-01-01

    Understanding the fate and toxicity of environmental contaminants is essential to framing practical management decisions. Forms and bioavailable concentrations often change over time due to natural physical, chemical, and biological processes. For some sites, hundreds of contaminants may be of initial interest, and even small projects can involve a substantial number of contaminants. With multiple assessments common, attention to effectiveness and efficiency is important, and integrating fate and toxicity information provides a valuable way to focus the analyses. Fate assessments help identify what forms may be present where and when, while toxicity information indicates what health effects could result if people were exposed. The integration process is illustrated by an application for the Hanford site, to support long-term management decisions for the cesium and strontium capsules. Fate data, health-based benchmarks, and related toxicity information were effectively combined to indicate performance targets for chemicals and radionuclides identified for capsule leachate that could migrate to groundwater. More than 50 relevant benchmarks and toxicity context were identified for 15 of the 17 study contaminants; values for chronic drinking water exposure provided the common basis for selected indicators. For two chemicals, toxicity information was identified from the scientific literature to guide the performance targets. (authors)

  9. The toxicity of oil-contaminated muskeg following biodegradation

    International Nuclear Information System (INIS)

    Farwell, A.; Kelly-Hooper, F.; McAlear, J.; Sinnesael, K.; Dixon, D.

    2009-01-01

    The current environmental criteria for the maximum allowable levels of hydrocarbons resulting from an oil spill assume that all detectable hydrocarbons are petroleum hydrocarbons (PHC) and do not account for naturally-occurring biogenic hydrocarbons (BHC). As such, some soils may be wrongfully assessed as being PHC contaminated. A false identification could lead to unnecessary and costly bioremediation that is potentially disruptive to functioning ecosystems. This study is part of a larger project to differentiate between natural and petroleum F3 hydrocarbons in muskeg material that has been impacted by an oil spill. The toxicity of oil-contaminated muskeg was examined following biodegradation in laboratory microcosms. Preliminary acute toxicity tests using locally purchased Sphagnum peat moss contaminated with Federated Crude oil had no effect on the survival of earthworms (Eisenia andrei), but springtails (Orthonychiurus folsomi) were more sensitive. Earthworm and springtail reproduction bioassays and a Northern wheatgrass (Elymus lanceolatus) growth bioassay was used to test the crude-oil-contaminated peat. All 3 test species will be used to test for reduced toxicity following biodegradation of Federated Crude oil-contaminated muskeg from northern Alberta under simulated conditions.

  10. The toxicity of oil-contaminated muskeg following biodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Farwell, A.; Kelly-Hooper, F.; McAlear, J.; Sinnesael, K.; Dixon, D. [Waterloo Univ., Waterloo, ON (Canada)

    2009-07-01

    The current environmental criteria for the maximum allowable levels of hydrocarbons resulting from an oil spill assume that all detectable hydrocarbons are petroleum hydrocarbons (PHC) and do not account for naturally-occurring biogenic hydrocarbons (BHC). As such, some soils may be wrongfully assessed as being PHC contaminated. A false identification could lead to unnecessary and costly bioremediation that is potentially disruptive to functioning ecosystems. This study is part of a larger project to differentiate between natural and petroleum F3 hydrocarbons in muskeg material that has been impacted by an oil spill. The toxicity of oil-contaminated muskeg was examined following biodegradation in laboratory microcosms. Preliminary acute toxicity tests using locally purchased Sphagnum peat moss contaminated with Federated Crude oil had no effect on the survival of earthworms (Eisenia andrei), but springtails (Orthonychiurus folsomi) were more sensitive. Earthworm and springtail reproduction bioassays and a Northern wheatgrass (Elymus lanceolatus) growth bioassay was used to test the crude-oil-contaminated peat. All 3 test species will be used to test for reduced toxicity following biodegradation of Federated Crude oil-contaminated muskeg from northern Alberta under simulated conditions.

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

    International Nuclear Information System (INIS)

    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

  12. Contamination of the Arctic by exotic air toxics

    International Nuclear Information System (INIS)

    Ford, J.; Landers, D.

    1991-01-01

    Various kinds of atmospheric pollutants are commonly known to occur in arctic environments. These include organic contaminants, pollutants associated with fossil fuel combustion, smelting, industrial development, and radionuclides. Recently, additional concern has arisen from studies suggesting that at least some atmospheric contaminants may be susceptible to poleward redistribution as a result of their physical and chemical properties. Thus, contamination of the arctic may be exacerbated by the tendency of selected contaminants produced at lower latitudes to be transported to polar regions and incorporated into high latitude food chains. Although awareness of exotic contaminants in high latitude food chains is not new, regional baseline data are needed to document the spatial extent and magnitude of this potentially serious problem. The US Arctic is little studied in this regard relative to several other circumpolar nations (e.g., Canada, Sweden); over the next year the authors will be designing a regional survey to begin remedying this information gap. A major focus of this activity will be to ensure compatibility with both ongoing international studies of arctic contamination, and the USEPA Environmental Monitoring and Assessment Program. Issues related to sampling design will be outlined and discussed

  13. Assessing sediment contamination using six toxicity assays

    OpenAIRE

    Allen G. BURTON Jr.; Carolyn ROWLAND; Renato BAUDO; Monica BELTRAMI

    2001-01-01

    An evaluation of sediment toxicity at Lake Orta, Italy was conducted to compare a toxicity test battery of 6 assays and to evaluate the extent of sediment contamination at various sediment depths. Lake Orta received excessive loadings of copper and ammonia during the 1900’s until a large remediation effort was conducted in 1989-90 using lime addition. Since that time, the lake has shown signs of a steady recovery of biological communities. The study results showed acute toxicity still exists ...

  14. Nanoparticle interactions with co-existing contaminants: joint toxicity, bioaccumulation and risk.

    Science.gov (United States)

    Deng, Rui; Lin, Daohui; Zhu, Lizhong; Majumdar, Sanghamitra; White, Jason C; Gardea-Torresdey, Jorge L; Xing, Baoshan

    2017-06-01

    With their growing production and application, engineered nanoparticles (NPs) are increasingly discharged into the environment. The released NPs can potentially interact with pre-existing contaminants, leading to biological effects (bioaccumulation and/or toxicity) that are poorly understood. Most studies on NPs focus on single analyte exposure; the existing literature on joint toxicity of NPs and co-existing contaminants is rather limited but beginning to develop rapidly. This is the first review paper evaluating the current state of knowledge regarding the joint effects of NPs and co-contaminants. Here, we review: (1) methods for investigating and evaluating joint effects of NPs and co-contaminants; (2) simultaneous toxicities from NPs co-exposed with organic contaminants, metal/metalloid ions, dissolved organic matter (DOM), inorganic ligands and additional NPs; and (3) the influence of NPs co-exposure on the bioaccumulation of organic contaminants and heavy metal ions, as well as the influence of contaminants on NPs bioaccumulation. In addition, future research needs are discussed so as to better understand risk associated with NPs-contaminant co-exposure.

  15. Toxic element contamination of natural health products and pharmaceutical preparations.

    Directory of Open Access Journals (Sweden)

    Stephen J Genuis

    Full Text Available BACKGROUND: Concern has recently emerged regarding the safety of natural health products (NHPs-therapies that are increasingly recommended by various health providers, including conventional physicians. Recognizing that most individuals in the Western world now consume vitamins and many take herbal agents, this study endeavored to determine levels of toxic element contamination within a range of NHPs. METHODS: Toxic element testing was performed on 121 NHPs (including Ayurvedic, traditional Chinese, and various marine-source products as well as 49 routinely prescribed pharmaceutical preparations. Testing was also performed on several batches of one prenatal supplement, with multiple samples tested within each batch. Results were compared to existing toxicant regulatory limits. RESULTS: Toxic element contamination was found in many supplements and pharmaceuticals; levels exceeding established limits were only found in a small percentage of the NHPs tested and none of the drugs tested. Some NHPs demonstrated contamination levels above preferred daily endpoints for mercury, cadmium, lead, arsenic or aluminum. NHPs manufactured in China generally had higher levels of mercury and aluminum. CONCLUSIONS: Exposure to toxic elements is occurring regularly as a result of some contaminated NHPs. Best practices for quality control-developed and implemented by the NHP industry with government oversight-is recommended to guard the safety of unsuspecting consumers.

  16. Toxicity of contaminants in lagoons and pannes of the Indiana Dunes National Lakeshore

    International Nuclear Information System (INIS)

    Gillespie, R.; Speelman, J.; Stewart, P.M.

    1995-01-01

    Contaminants in water and sediments of lagoons and pannes were 2--90 times greater at sites adjacent to slag and coal piles than those at reference sites. One site (Lagoon-US5) had sediments with very high concentrations of toxic organics (e.g. naphthalene, phenanthrene, dibenzofuran). Although analyses indicated a gradient of contaminant concentration with distance from their sources, toxicity assays were somewhat equivocal. With the exception of less reproduction in Ceriodaphnia at one lagoon site (US3 = 0.55 of reference), survival of fathead minnows and reproduction in Ceriodaphnia in lagoon and panne waters varied independently of the contaminant concentration. In fact, there was better Ceriodaphnia reproduction in water from two contaminated sites (Lagoon-US5, Panne-WP1) than in water from reference sites. Fathead minnow survival, Ceriodaphnia survival, Ceriodaphnia reproduction, amphipod survival, and amphipod growth varied among sites in toxicity assays with sediments, 100% mortality of fatheads at Lagoon-US5, 100% mortality of Ceriodaphnia at Lagoon-US3, and less survival of fathead minnows at Lagoon-US3 indicate possible toxicity from contaminants in sediments at these sites. Of all organisms and end-points tested, Ceriodaphnia survival seemed to be most closely associated with concentrations of contaminants in lagoon water and sediments. Amphipod survival also varied with contaminants in sediments, however, survival in sediments of contaminated sites ranged only from 0.90--0.93 of reference sites. Although the results are not consistent among organisms, toxicity assays indicate that sediments from the lagoon site with the highest contaminants (Lagoon-US5) and possibly those from another contaminated lagoon site (Lagoon-US3) could be toxic to aquatic organisms. Water and sediments from contaminated panne sites do not appear to be toxic to aquatic test organisms

  17. Comparative In Vitro Biological Toxicity of Four Kinds of Air Pollution Particles.

    Science.gov (United States)

    Shin, Han-Jae; Cho, Hyun Gi; Park, Chang Kyun; Park, Ki Hong; Lim, Heung Bin

    2017-10-01

    Accumulating epidemiological evidence indicates that exposure to fine air pollution particles (APPs) is associated with a variety of adverse health effects. However, the exact physiochemical properties and biological toxicities of fine APPs are still not well characterized. We collected four types of fine particle (FP) (diesel exhaust particles [DEPs], natural organic combustion [NOC] ash, synthetic organic combustion [SOC] ash, and yellow sand dust [YSD]) and investigated their physicochemical properties and in vitro biological toxicity. DEPs were almost entirely composed of ultrafine particles (UFPs), while the NOC, SOC, and YSD particles were a mixture of UFPs and FPs. The main elements in the DEPs, NOC ash, SOC ash, and YSD were black carbon, silicon, black carbon, and silicon, respectively. DEPs exhibited dose-dependent mutagenicity even at a low dose in Salmonella typhimurium TA 98 and 100 strains in an Ames test for genotoxicity. However, NOC, SOC, and YSD particles did not show any mutagenicity at high doses. The neutral red uptake assay to test cell viability revealed that DEPs showed dose-dependent potent cytotoxicity even at a low concentration. The toxicity of DEPs was relatively higher than that of NOC, SOC, and YSD particles. Therefore, these results indicate that among the four FPs, DEPs showed the highest in vitro biological toxicity. Additional comprehensive research studies such as chemical analysis and in vivo acute and chronic inhalation toxicity tests are necessary to determine and clarify the effects of this air contaminant on human health.

  18. Regenerable Air Purification System for Gas-Phase Contaminant Control

    Science.gov (United States)

    Constantinescu, Ileana C.; Finn, John E.; LeVan, M. Douglas; Lung, Bernadette (Technical Monitor)

    2000-01-01

    Tests of a pre-prototype regenerable air purification system (RAPS) that uses water vapor to displace adsorbed contaminants from an adsorbent column have been performed at NASA Ames Research Center. A unit based on this design can be used for removing trace gas-phase contaminants from spacecraft cabin air or from polluted process streams including incinerator exhaust. During the normal operation mode, contaminants are removed from the air on the column. Regeneration of the column is performed on-line. During regeneration, contaminants are displaced and destroyed inside the closed oxidation loop. In this presentation we discuss initial experimental results for the performance of RAPS in the removal and treatment of several important spacecraft contaminant species from air.

  19. 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.

  20. 2011 NATA - Air Toxics Monitors

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset includes annual (2005 - 2013) statistics of measured ambient air toxics concentrations (in micrograms per cubic meter) and associated risk estimates for...

  1. Cleaning products and air fresheners: exposure to primary and secondary air pollutants

    DEFF Research Database (Denmark)

    Nazaroff, W.; Weschler, Charles J.

    2004-01-01

    Building occupants, including cleaning personnel, are exposed to a wide variety of airborne chemicals when cleaning agents and air fresheners are used in buildings. Certain of these chemicals are listed by the state of California as toxic air contaminants (TACs) and a subset of these are regulated...... by the US federal government as hazardous air pollutants (HAPs). California's Proposition 65 list of species recognized as carcinogens or reproductive toxicants also includes constituents of certain cleaning products and air fresheners. In addition, many cleaning agents and air fresheners contain chemicals...... that can react with other air contaminants to yield potentially harmful secondary products. For example, terpenes can react rapidly with ozone in indoor air generating many secondary pollutants, including TACs such as formaldehyde. Furthermore, ozone-terpene reactions produce the hydroxyl radical, which...

  2. Concentration and toxicity of sea-surface contaminants in Puget Sound

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, J.T.; Crecelius, E.A.; Kocan, R.

    1986-04-01

    The Marine Research Laboratory conducted studies during CY 1985 to evaluate the effects of sea-surface contamination on the reproductive success of a valued marine species. Microlayer and bulk water samples were collected from a rural bay, central Puget Sound, and three urban bays and analyzed for a number of metal and organic contaminants as well as for densities of neuston and plankton organisms. Fertilized neustonic eggs of sand sole (Psettichthys melanostictus) were exposed to the same microlayer samples during their first week of embryonic and larval development. Also, we evaluated the effects of microlayer extracts on the growth of trout cell cultures. Compared to rural sites, urban bays generally contained lower densities of neustonic flatfish eggs during the spawning season. Also, in contrast to the rural sites or the one central Puget Sound site, approximately half of the urban bay microlayer samples resulted in significant increases in embryo mortality (up to 100%), kyphosis (bent spine abnormalities) in hatched larvae, increased anaphase aberrations in developing embryos, and decreased trout cell growth. The toxic samples generally contained high concentrations of polycyclic aromatic and/or chlorinated hydrocarbons and/or potentially toxic metals. In some cases, concentrations of contaminants on the sea surface exceeded water-quality criteria by several orders of magnitude. Several samples of subsurface bulk water collected below highly contaminated surfaces showed no detectable contamination or toxicity.

  3. Air toxics regulatory issues facing urban settings

    Energy Technology Data Exchange (ETDEWEB)

    Olden, K.; Guthrie, J. [National Institute of Environmental Health Sciences, Research Triangle Park, NC (United States)

    1996-10-01

    Biomarker research does not exist in isolation. Its usefulness can only be realized when it is translated into prevention strategies to protect public health. In the context of air toxics, these prevention strategies begin with the development of regulatory standards derived from risk assessment schemes. The Clean Air Act Amendments of 1990 list 189 air toxics, including many volatile organics, metals, and pesticides. The National Institute of Environmental Health Sciences (NIEHS), through its affiliation with the National Toxicology Program, has generated toxicity and carcinogenicity data on more than 100 of these air toxics. The NIEHS extramural and intramural research portfolios support a variety of projects that develop and validate biomarkers for use in environmental health science and risk assessment. Biomarkers have a tremendous potential in the areas of regulating air toxics and protecting public health. Risk assessors need data provided by biomarkers of exposure, biomarkers of close/pharmacokinetics, biomarkers of susceptibility or individual variability, and biomarkers of effects. The greatest benefit would be realized if biomarkers could be employed in four areas of primary and secondary prevention. The first is the use of biomarkers to enhance extrapolation of animal data to human exposure situations in establishing risk standards. The second is the use of biomarkers that assess noncancer, as well as cancer, end points. Important health end points include pulmonary dysfunction, immunotoxicity, and neurotoxicity. Third, biomarkers that serve as early warning signs to detect intermediate effects would enhance our ability to design timely and cost-effective intervention strategies. Finally, biomarkers used to evaluate the effectiveness of intervention strategies both in clinical and regulatory settings, would enable us to ensure that programs designed to protect public health do, in fact, achieve the desired outcome. 9 refs., 2 tabs.

  4. Air contamination for predicting wound contamination in clean surgery: A large multicenter study.

    Science.gov (United States)

    Birgand, Gabriel; Toupet, Gaëlle; Rukly, Stephane; Antoniotti, Gilles; Deschamps, Marie-Noelle; Lepelletier, Didier; Pornet, Carole; Stern, Jean Baptiste; Vandamme, Yves-Marie; van der Mee-Marquet, Nathalie; Timsit, Jean-François; Lucet, Jean-Christophe

    2015-05-01

    The best method to quantify air contamination in the operating room (OR) is debated, and studies in the field are controversial. We assessed the correlation between 2 types of air sampling and wound contaminations before closing and the factors affecting air contamination. This multicenter observational study included 13 ORs of cardiac and orthopedic surgery in 10 health care facilities. For each surgical procedure, 3 microbiologic air counts, 3 particles counts of 0.3, 0.5, and 5 μm particles, and 1 bacteriologic sample of the wound before skin closure were performed. We collected data on surgical procedures and environmental characteristics. Of 180 particle counts during 60 procedures, the median log10 of 0.3, 0.5, and 5 μm particles was 7 (interquartile range [IQR], 6.2-7.9), 6.1 (IQR, 5.4-7), and 4.6 (IQR, 0-5.2), respectively. Of 180 air samples, 50 (28%) were sterile, 90 (50%) had 1-10 colony forming units (CFU)/m(3) and 40 (22%) >10 CFU/m(3). In orthopedic and cardiac surgery, wound cultures at closure were sterile for 24 and 9 patients, 10 and 11 had 1-10 CFU/100 cm(2), and 0 and 6 had >10 CFU/100 cm(2), respectively (P air microbial counts (P contamination (P = .22). This study suggests that particle counting is a good surrogate of airborne microbiologic contamination in the OR. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  5. Air toxics and the 1990 Clean Air Act: Managing trace element emissions

    International Nuclear Information System (INIS)

    Chow, W.; Levin, L.; Miller, M.J.

    1992-01-01

    The US Environmental Protection Agency (EPA) has historically regulated air toxics (hazardous air pollutants) under Section 112 of the Clean Air Act. To date, EPA has established emission standards for 8 hazardous air pollutants (arsenic, asbestos, benzene, beryllium, mercury, radionuclides, coke oven emissions and vinyl chloride). The US electric utility industry was not determined to be a source category requiring regulation for any of the eight chemicals. Of the eight, radionuclides were the last species for which EPA established hazardous emissions standards. In this instance, EPA determined that the risks associated with electric utility fossil fuel power plant emissions were sufficiently low that they should not be regulated. However, the 1990 Clean Air Act Amendments require a new evaluation of the electric utility industry emissions of hazardous air pollutants. This paper summarizes the key features of the air toxics provisions of the Clean Air Act Amendments, describes EPRI's activities on the subject, and provides some preliminary insights from EPRI's research to date

  6. Direct measurement of homogeneously distributed radioactive air contamination with germanium detectors

    International Nuclear Information System (INIS)

    Sowa, W.

    1990-01-01

    Air contamination by γ emitting radionuclides was measured with a vertically arranged germanium detector, laterally shielded by a lead ring, and calibration factors and detection limits of a number of fission products determined. The possibility of measuring simultaneously existing air and soil contamination by measurements with and without lead shield is described. The change of detection limit of air contamination is presented for different soil contamination levels by the same radionuclide. Calibration factors are given to determine the dose rate on the ground due to air contamination by different radionuclides. (author)

  7. 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).

  8. Assessing sediment contamination using six toxicity assays

    Directory of Open Access Journals (Sweden)

    Allen G. BURTON Jr.

    2001-08-01

    Full Text Available An evaluation of sediment toxicity at Lake Orta, Italy was conducted to compare a toxicity test battery of 6 assays and to evaluate the extent of sediment contamination at various sediment depths. Lake Orta received excessive loadings of copper and ammonia during the 1900’s until a large remediation effort was conducted in 1989-90 using lime addition. Since that time, the lake has shown signs of a steady recovery of biological communities. The study results showed acute toxicity still exists in sediments at a depth of 5 cm and greater. Assays that detected the highest levels of toxicity were two whole sediment exposures (7 d using Hyalella azteca and Ceriodaphnia dubia. The MicrotoxR assay using pore water was the third most sensitive assay. The Thamnotox, Rototox, Microtox solid phase, and Seed Germination-Root Elongation (pore and solid phase assays showed occasional to no toxicity. Based on similarity of responses and assay sensitivity, the two most useful assays were the C. dubia (or H. azteca and Microtox pore water. These assays were effective at describing sediment toxicity in a weight-of-evidence approach.

  9. Phytoremediation of soils contaminated with toxic elements and radionuclides

    International Nuclear Information System (INIS)

    Cornish, J.E.; Goldberg, W.C.; Levine, R.S.; Benemann, J.R.

    1995-01-01

    At many US Department of Energy (US DOE) facilities and other sites, surface soils over relatively large areas are contaminated with heavy metals, radionuclides, and other toxic elements, often at only a relatively small factor above regulatory action levels. Cleanup of such sites presents major challenges, because currently available soil remediation technologies can be very expensive. In response, the US DOE's Office of Technology Development, through the Western Environmental Technology Office, is sponsoring research in the area of phytoremediation. Phytoremediation is an emerging technology that uses higher plants to transfer toxic elements and radionuclides from surface soils into aboveground biomass. Some plants, termed hyperaccumulators, take up toxic elements in substantial amounts, resulting in concentrations in aboveground biomass over 100 times those observed with conventional plants. After growth, the plant biomass is harvested, and the toxic elements are concentrated and reclaimed or disposed of. As growing, harvesting, and processing plant biomass is relatively inexpensive, phytoremediation can be a low-cost technology for remediation of extensive areas having lightly to moderately contaminated soils. This paper reviews the potential of hyper- and moderate accumulator plants in soil remediation, provides some comparative cost estimates, and outlines ongoing work initiated by the US DOE

  10. Temporal and spatial trends in sediment contaminants associated with toxicity in California watersheds

    International Nuclear Information System (INIS)

    Siegler, Katie; Phillips, Bryn M.; Anderson, Brian S.; Voorhees, Jennifer P.; Tjeerdema, Ron S.

    2015-01-01

    California's Stream Pollution Trends program (SPoT) assesses long-term water quality trends, using 100 base-of-the-watershed sampling sites. Annual statewide sediment surveys from 2008 to 2012 identified consistent levels of statewide toxicity (19%), using the freshwater amphipod Hyalella azteca. Significant contaminant trends included a decrease in PCBs, stable concentrations of metals and PAHs, and a statewide increase in detections and concentrations of pyrethroid pesticides. The pyrethroid pesticide bifenthrin was detected in 69% of samples (n = 410). Detection of toxicity increased in a subset of samples tested at a more environmentally relevant test temperature (15 °C), and the magnitude of toxicity was much greater, indicating pyrethroid pesticides as a probable cause. Pyrethroid toxicity thresholds (LC50) were exceeded in 83% of samples with high toxicity. Principal components analysis related pyrethroids, metals and total organic carbon to urban land use. - Highlights: • Toxicity and contaminant concentrations were higher in urban dominated watersheds. • Average and range of total pyrethroid concentrations increased between 2008 and 2012. • Pyrethroid toxicity thresholds (LC50) were exceeded in 83% of samples with high toxicity. - Detections and concentrations of current use pesticides are increasing in California urban watersheds, while legacy organochlorine contaminants are decreasing statewide.

  11. Joint use of laboratory bioassays and field-collected plants to evaluate toxicity and contaminant bioaccumulation

    International Nuclear Information System (INIS)

    Long, S.P.; Byron, E.R.; Ohlendorf, H.M.

    1995-01-01

    Soil toxicity tests using lettuce (Latuca saliva) were conducted using soil samples collected as part of ecological risk assessments at two facilities in California. At some sites, terrestrial plants were collected in the field for chemical analysis. Ecological concerns focused on exposures to plants, phytophagous insects, and their secondary consumers, such as birds and small mammals. The toxicity tests were used to assess potential exposures to a variety of site-specific contaminants including organochlorine pesticides, PCBs, PAHs, petroleum hydrocarbons, heavy metals, and other inorganic substances. Site soils were combined with clean control soils to produce toxicity test soil dilutions containing 100%, 75%, 50%, 25%, and 0% site soils. Observations of seed germination and growth were made at day 0, 7, 14, 21 and 28. Toxicity test results were combined with soil chemical analytical results and physical characteristics to establish NOAELs and LOAELs. Bioaccumulation in the lettuce and field-collected plants was evaluated by comparing plant contaminant to soil contaminant concentrations. Allometric equations and sublethal toxicity data were used to predict potential effects on birds and small mammals. Whole-body contaminant concentrations in insects collected on some of the plants in the field were also considered in evaluating the potential for toxicity to insectivorous birds. The study indicated that contaminant uptake was occurring in the field-collected and bioassay plants but not the insects. Site factors in addition to soil contaminant concentration influenced the potential for plant toxicity and bioaccumulation

  12. Air toxics: A new concern for the utility industry

    International Nuclear Information System (INIS)

    Torrens, I.; Chow, W.

    1992-01-01

    The 1990 Clean Air Acts Amendments call for EPA studies on utility emissions of potentially hazardous air pollutants and their impact, prior to any decision on regulation of these emissions. The Electric Power Research Institute is carrying out a comprehensive assessment of air toxics risk assessment, consisting of data compilation and analysis, field measurements of priority air toxics at power plants and test facilities, atmospheric transport and deposition, and health/ecological risk assessment. The paper reports on progress to data and objectives of the EPRI assessment

  13. Acute toxicity assessment of explosive-contaminated soil extracting solution by luminescent bacteria assays.

    Science.gov (United States)

    Xu, Wenjie; Jiang, Zhenming; Zhao, Quanlin; Zhang, Zhenzhong; Su, Hongping; Gao, Xuewen; Ye, Zhengfang

    2016-11-01

    Explosive-contaminated soil is harmful to people's health and the local ecosystem. The acute toxicity of its extracting solution was tested by bacterial luminescence assay using three kinds of luminescent bacteria to characterize the toxicity of the soil. An orthogonal test L 16 (4 5 ) was designed to optimize the soil extracting conditions. The optimum extracting conditions were obtained when the ultrasonic extraction time, ultrasonic extraction temperature, and the extraction repeat times were 6 h, 40 °C, and three, respectively. Fourier transform infrared spectroscopy (FTIR) results showed that the main components of the contaminated soil's extracting solution were 2,4-dinitrotoluene-3-sulfonate (2,4-DNT-3-SO 3 - ); 2,4-dinitrotoluene-5-sulfonate (2,4-DNT-5-SO 3 - ); and 2,6-dinitrotoluene (2,6-DNT). Compared with Photobacterium phosphoreum and Vibrio fischeri, Vibrio qinghaiensis sp. Nov. is more suitable for assessing the soil extracting solution's acute toxicity. Soil washing can remove most of the contaminants toxic to luminescent bacterium Vibrio qinghaiensis sp. Nov., suggesting that it may be a potential effective remediation method for explosive-contaminated soil.

  14. Effect of soil contaminant extraction method in determining toxicity using the Microtox(reg.) assay

    International Nuclear Information System (INIS)

    Harkey, G.A.; Young, T.M.

    2000-01-01

    This project examined the influence of different extraction methods on the measured toxicity of contaminated soils collected from manufactured gas plant (MGP) sites differing in soil composition and contaminant concentration. Aged soils from a number of MGP sites were extracted using a saline solution, supercritical fluid extraction (SFE), and Soxhlet extraction. Toxicity was assessed using two forms of Microtox tests: acute aqueous tests on saline and SFE soil extracts and solid-phase tests (SPTs) on soil particles. Microtox SPTs were performed on soils before and after SFE to determine resulting toxicity reduction. Three hypotheses were tested: (1) Toxicity of soil extracts is related to contaminant concentrations of the extracts, (2) measured toxicity significantly decreases with less vigorous methods of extraction, and (3) supercritical fluid extractability correlates with measured toxicity. The EC50s for SPTs performed before and after SFE were not different for some soils but were significantly greater after extraction for other soils tested. The most significant toxicity reductions were observed for soils exhibiting the highest toxicity in both preextraction SPTs and acute aqueous tests. Acute Microtox tests performed on SFE extracts showed significantly lower EC50s than those reported from saline-based extraction procedures. Toxicity of the soils measured by Microtox SPTs was strongly correlated with both SFE efficiency and measures of contaminant aging. Data from this project provide evidence of sequestration and reduced availability of polycyclic aromatic hydrocarbons (PAHs) from soils extracted via physiologically based procedures compared to vigorous physical extraction protocols

  15. In situ and laboratory bioassays with Chironomus riparius larvae to assess toxicity of metal contamination in rivers: the relative toxic effect of sediment versus water contamination.

    Science.gov (United States)

    Faria, Mafalda S; Lopes, Ricardo J; Nogueira, António J A; Soares, Amadeu M V M

    2007-09-01

    We used bioassays employing head capsule width and body length increase of Chironomus riparius larvae as end points to evaluate metal contamination in streams. Bioassays were performed in situ near an abandoned Portuguese goldmine in the spring of 2003 and 2004. Bioassays also were performed under laboratory conditions with water and sediment collected from each stream to verify if laboratory bioassays could detect in situ toxicity and to evaluate the relative contribution of sediment and water to overall toxicity. We used field sediments with control water and control sediments with field water to discriminate between metal contamination in water and sediment. Field water with dry and sieved, organic matter-free, and nontreated sediments was used to determine the toxicity of heavy metals that enter the organism through ingested material. In both in situ and laboratory bioassays, body length increase was significantly inhibited by metal contamination, whereas head capsule width was not affected. Body length increase was more affected by contaminated sediment compared to contaminated water. The lowest-effect level of heavy metals was observed in the dry and sieved sediment that prevented ingestion of sediment particles by larvae. These results suggest that body length increase of C. riparius larvae can be used to indicate the impact of metal contamination in rivers. Chironomus riparius larvae are more affected by heavy metals that enter the organism through ingested sediment than by heavy metals dissolved in the water column. Nevertheless, several factors, such as the particle size and organic matter of sediment, must be taken into account.

  16. Sediment and toxic contaminant transport modeling in coastal waters

    International Nuclear Information System (INIS)

    Onishi, Y.; Mayer, D.W.; Argo, R.S.

    1982-02-01

    A hydrodynamic model, CAFE-I, a wave refraction model, LO3D, and a sediment and contaminant transport model, FETRA, were selected as tools for evaluating exposure levels of radionuclides, heavy metals, and other toxic chemicals in coastal waters. Prior to the application of these models to the Irish Sea and other coastal waters, the finite element model, FETRA, was tested to demonstrate its ability to simulate sediment and contaminant interactions (e.g., adsorption and desorption), and the mechanisms governing the transport, deposition, and resuspension of contaminated sediments

  17. Air toxics from heavy oil production and consumption

    International Nuclear Information System (INIS)

    Lipfert, F.W.; DePhillips, M.P.; Moskowitz, P.D.

    1992-01-01

    This report assesses the potential impact of recent Federal and state regulations for airborne toxic substances on the production and consumption of heavy fuel oils. Emissions of nickel from heavy oil production in California are considered in some detail, in conjunction with California state regulations for toxic emissions. Although the use of thermal energy from heavy crude oils could in theory be impacted by toxic air pollution regulations, recent trends towards the use of natural gas for the required extraction energy appear to provide substantial relief, in addition to reducing emissions of criteria air pollutants. However, the consumption of residual fuel oils containing toxic metals could result in higher population exposures to these substances and their attendant risks may be worthy of more detailed analysis

  18. Characterizing toxicity of metal-contaminated sediments from mining areas

    Science.gov (United States)

    Besser, John M.; Brumbaugh, William G.; Ingersoll, Christopher G.

    2015-01-01

    This paper reviews methods for testing the toxicity of metals associated with freshwater sediments, linking toxic effects with metal exposure and bioavailability, and developing sediment quality guidelines. The most broadly applicable approach for characterizing metal toxicity is whole-sediment toxicity testing, which attempts to simulate natural exposure conditions in the laboratory. Standard methods for whole-sediment testing can be adapted to test a wide variety of taxa. Chronic sediment tests that characterize effects on multiple endpoints (e.g., survival, growth, and reproduction) can be highly sensitive indicators of adverse effects on resident invertebrate taxa. Methods for testing of aqueous phases (pore water, overlying water, or elutriates) are used less frequently. Analysis of sediment toxicity data focuses on statistical comparisons between responses in sediments from the study area and responses in one or more uncontaminated reference sediments. For large or complex study areas, a greater number of reference sediments is recommended to reliably define the normal range of responses in uncontaminated sediments – the ‘reference envelope’. Data on metal concentrations and effects on test organisms across a gradient of contamination may allow development of concentration-response models, which estimate metal concentrations associated with specified levels of toxic effects (e.g. 20% effect concentration or EC20). Comparisons of toxic effects in laboratory tests with measures of impacts on resident benthic invertebrate communities can help document causal relationships between metal contamination and biological effects. Total or total-recoverable metal concentrations in sediments are the most common measure of metal contamination in sediments, but metal concentrations in labile sediment fractions (e.g., determined as part of selective sediment extraction protocols) may better represent metal bioavailability. Metals released by the weak-acid extraction

  19. CAirTOX: A compartment model for assessing the fate of and human exposure to toxic-chemical emissions to air

    Energy Technology Data Exchange (ETDEWEB)

    McKone, T.E.

    1993-10-01

    CAirTOX has been developed as a spreadsheet model to assist in making a risk assessment of toxic air emissions. With CAirTOX, one 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 multimedia transport and transformation model is a steady-state, but non-equilibrium model that can be used to assess concentrations of contaminants released continuously to air. In Part 1, the authors describe the multimedia transport and transformation model used to determine the fate of air emissions. In Part 2, they describe inputs and data needs for CAirTOX and the development of a set of landscape factors, which can be used to represent regional air basin/water-shed systems in California. In Part 3, they describe the multiple-pathway exposure scenarios and exposure algorithms. In Part 4, they compare the HRA approach and results and the CAirTOX exposure equations. In Part 5, they consider model sensitivity and uncertainty to determine how variability and uncertainty in model inputs affects the precision, accuracy, and credibility of the model output.

  20. Characterizing toxicity of metal-contaminated sediments from mining areas

    International Nuclear Information System (INIS)

    Besser, John M.; Brumbaugh, William G.; Ingersoll, Christopher G.

    2015-01-01

    Highlights: • We review methods for testing toxicity of sediments affected by metals. • Toxicity testing provides site-specific assessment of impacts on resident biota. • Goals are to document extent of toxicity and associations with metal exposure. • Need to characterize bioavailability of metals in sediment and pore water. • Toxicity data is basis for guidelines used to predict hazards of metal toxicity. - Abstract: This paper reviews methods for testing the toxicity of metals associated with freshwater sediments, linking toxic effects with metal exposure and bioavailability, and developing sediment quality guidelines. The most broadly applicable approach for characterizing metal toxicity is whole-sediment toxicity testing, which attempts to simulate natural exposure conditions in the laboratory. Standard methods for whole-sediment testing can be adapted to test a wide variety of taxa. Chronic sediment tests that characterize effects on multiple endpoints (e.g., survival, growth, and reproduction) can be highly sensitive indicators of adverse effects on resident invertebrate taxa. Methods for testing of aqueous phases (pore water, overlying water, or elutriates) are used less frequently. Analysis of sediment toxicity data focuses on statistical comparisons between responses in sediments from the study area and responses in one or more uncontaminated reference sediments. For large or complex study areas, a greater number of reference sediments is recommended to reliably define the normal range of responses in uncontaminated sediments – the ‘reference envelope’. Data on metal concentrations and effects on test organisms across a gradient of contamination may allow development of concentration-response models, which estimate metal concentrations associated with specified levels of toxic effects (e.g. 20% effect concentration or EC20). Comparisons of toxic effects in laboratory tests with measures of impacts on resident benthic invertebrate

  1. Joint use of laboratory bioassays and field-collected invertebrates to evaluate toxicity and contaminant bioaccumulation

    International Nuclear Information System (INIS)

    Long, S.P.; Byron, E.R.; Ohlendorf, H.M.

    1995-01-01

    Soil toxicity tests using earthworms (Eisenia andrei) were conducted using soil samples collected as part of ecological risk assessments for several sites at two facilities in California. At some sites, earthworms or other terrestrial invertebrates were collected in the field for chemical analysis. Ecological concerns focused on exposures to soil invertebrates and their secondary consumers, such as birds and small mammals. The toxicity tests were used to assess potential exposures to a variety of site-specific contaminants including organochlorine pesticides, PCBs, PAHs, petroleum hydrocarbons, heavy metals, and other inorganic substances. Site soils were combined with clean control soils to produce toxicity test soil dilutions containing 100%, 75%, 50%, 25%, and 0% site soils. Earthworm mortality and other observations were made at day 0, 7, 14, 21 and 28. Toxicity test results were combined with soil chemical analytical results and physical characteristics to establish NOAELs and LOAELs. Bioaccumulation in the laboratory earthworms and field-collected invertebrates was evaluated by comparing whole-body contaminant to soil contaminant concentrations. Allometric equations and sublethal toxicity data were used to predict potential effects on birds and small mammals. Earthworm toxicity tests indicated a wide range of sensitivity to on-site contaminants and showed the importance of considering potential confounding influences due to soil parameters other than contaminant concentration

  2. CHEMICAL CONTAMINATION AND TOXICITY ASSOCIATED WITH A COASTAL GOLF COURSE COMPLEX

    Science.gov (United States)

    The increasing density of golf courses represents a potential source of contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to compare the concentrations of contaminants and toxicities of sedime...

  3. 29 CFR 1910.19 - Special provisions for air contaminants.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Special provisions for air contaminants. 1910.19 Section 1910.19 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION... Standards § 1910.19 Special provisions for air contaminants. (a) Asbestos, tremolite, anthophyllite, and...

  4. Environmental health: an analysis of available and proposed remedies for victims of toxic waste contamination

    International Nuclear Information System (INIS)

    Hurwitz, W.J.

    1981-01-01

    Past and present residents of the Love Canal area near Niagara Falls, New York, fear that they and their homes have been contaminated by toxic wastes seeping out from nearby chemical disposal sites. Hundreds of landfills nationwide are as potentially dangerous as Love Canal. In the absence of a statutory remedy, victims of contamination must rely upon common law theories of lability in order to recover damages for injuries suffered as a result of toxic waste contamination. This Note examines the merits and deficiencies of four common law theories: negligence, strict liability, nuisance and trespass. The Note concludes that none of these remedies is adequate to assure recovery to a person injured by toxic waste disposal, and recommends that legislation be adopted to ensure that victims of toxic waste contamination can be compensated for their injuries

  5. Toxicity assessment for petroleum-contaminated soil using terrestrial invertebrates and plant bioassays.

    Science.gov (United States)

    Hentati, Olfa; Lachhab, Radhia; Ayadi, Mariem; Ksibi, Mohamed

    2013-04-01

    The assessment of soil quality after a chemical or oil spill and/or remediation effort may be measured by evaluating the toxicity of soil organisms. To enhance our understanding of the soil quality resulting from laboratory and oil field spill remediation, we assessed toxicity levels by using earthworms and springtails testing and plant growth experiments. Total petroleum hydrocarbons (TPH)-contaminated soil samples were collected from an oilfield in Sfax, Tunisia. Two types of bioassays were performed. The first assessed the toxicity of spiked crude oil (API gravity 32) in Organization for Economic Co-operation and Development artificial soil. The second evaluated the habitat function through the avoidance responses of earthworms and springtails and the ability of Avena sativa to grow in TPH-contaminated soils diluted with farmland soil. The EC50 of petroleum-contaminated soil for earthworms was 644 mg of TPH/kg of soil at 14 days, with 67 % of the earthworms dying after 14 days when the TPH content reached 1,000 mg/kg. The average germination rate, calculated 8 days after sowing, varied between 64 and 74 % in low contaminated soils and less than 50 % in highly contaminated soils.

  6. Metabolic responses of Eisenia fetida after sub-lethal exposure to organic contaminants with different toxic modes of action

    Energy Technology Data Exchange (ETDEWEB)

    McKelvie, Jennifer R.; Wolfe, David M.; Celejewski, Magda A. [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada); Alaee, Mehran [Environment Canada, 867 Lakeshore Rd., P.O. Box 5050, Burlington, ON L7R 4A6 (Canada); Simpson, Andre J. [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada); Simpson, Myrna J., E-mail: myrna.simpson@utoronto.ca [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada)

    2011-12-15

    Nuclear magnetic resonance (NMR) - based metabolomics has the potential to identify toxic responses of contaminants within a mixture in contaminated soil. This study evaluated the metabolic response of Eisenia fetida after exposure to an array of organic compounds to determine whether contaminant-specific responses could be identified. The compounds investigated in contact tests included: two pesticides (carbaryl and chlorpyrifos), three pharmaceuticals (carbamazephine, estrone and caffeine), two persistent organohalogens (Aroclor 1254 and PBDE 209) and two industrial compounds (nonylphenol and dimethyl phthalate). Control and contaminant-exposed metabolic profiles were distinguished using principal component analysis and potential contaminant-specific biomarkers of exposure were found for several contaminants. These results suggest that NMR-based metabolomics offers considerable promise for differentiating between the different toxic modes of action (MOA) associated with sub-lethal toxicity to earthworms. - Highlights: > NMR-based earthworm metabolomic analysis of the toxic mode of action of various environmental contaminants. > Organic chemicals with different toxic modes of action resulted in varied metabolomic responses for E. fetida. > NMR-based metabolomics differentiates between the different modes of action associated with sub-lethal toxicity. - {sup 1}H NMR metabolomics was used to identify potential biomarkers of organic contaminant exposure in Eisenia fetida earthworms.

  7. Monitoring the levels of toxic air pollutants in the ambient air of ...

    African Journals Online (AJOL)

    user

    The ambient air quality in Freetown, Sierra Leone was investigated for the first time for toxic air pollutants. ..... 215 Switzerland), in a water bath at temperature of 55°C and pressure of ..... scraps. Furthermore, the prolonged use of generators.

  8. Formaldehyde: a candidate toxic air contaminant. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Frye, B.; Parker, T.

    1988-03-01

    Formaldehyde (HCHO) is a gas widely used in adhesives and resins, textiles, embalming fluids, fungicides, air fresheners, and cosmetics. It is directly emitted into the ambient outdoor air from vehicular and stationary sources, and is also produced in the atmosphere from other substances by photochemical smog processes. The International Agency for Research on Cancer (IARC) has determined that there is sufficient evidence for carcinogenicity of formaldehyde to animals, and limited evidence for carcinogenicity to humans. EPA classifies formaldehyde as a probable human carcinogen with a one in a million risk concentration of 0.08 ppb.

  9. Criteria and air-toxic emissions from in-use automobiles in the National Low-Emission Vehicle program.

    Science.gov (United States)

    Baldauf, Rich W; Gabele, Pete; Crews, William; Snow, Richard; Cook, J Rich

    2005-09-01

    The U.S. Environmental Protection Agency (EPA) implemented a program to identify tailpipe emissions of criteria and air-toxic contaminants from in-use, light-duty low-emission vehicles (LEVs). EPA recruited 25 LEVs in 2002 and measured emissions on a chassis dynamometer using the cold-start urban dynamometer driving schedule of the Federal Test Procedure. The emissions measured included regulated pollutants, particulate matter, speciated hydrocarbon compounds, and carbonyl compounds. The results provided a comparison of emissions from real-world LEVs with emission standards for criteria and air-toxic compounds. Emission measurements indicated that a portion of the in-use fleet tested exceeded standards for the criteria gases. Real-time regulated and speciated hydrocarbon measurements demonstrated that the majority of emissions occurred during the initial phases of the cold-start portion of the urban dynamometer driving schedule. Overall, the study provided updated emission factor data for real-world, in-use operation of LEVs for improved emissions modeling and mobile source inventory development.

  10. Air toxic emissions from burning of biomass globally-preliminary results

    International Nuclear Information System (INIS)

    Ward, D.E.; Hao, W.M.

    1992-01-01

    Emissions of trace gases, particles, and air toxic substances in the smoke plumes from biomass fires are of importance to global climate change. The potential impact of the air toxic emissions on the human population of specific regions globally is another major concern. The toxic materials are produced in high concentrations in areas of heavy biomass burning, e.g., Amazon Basin and Central/southern Africa. We provide new estimates of air toxics based on the combustion efficiency (percent of total carbon released as CO 2 ) for fires burning in different ecosystems on a global basis. Estimates of total biomass consumed on a global basis range from 2 to 10 Pg (1 petagram = 10 15 g) per year. We apply emission factors for various air toxics (g of emission released per kg of fuel consumed) to the estimate of global biomass consumption of 6.4 Pg per year. The principal air toxics analyzed in this paper include: Total particulate matter, CO, formaldehyde, acetaldehyde, acrolein, benzene, toluene, o-xylene, m, p-xylene, benzo[a]pyrene, and polycyclic organic material. The total emissions calculated for these materials on a yearly global basis are: 75, 362, 4.9, 1.5, 1.5, 2.1, 2.1, 0.3, 0.6, 0.001, 0.026, Tg (1 teragram = 10 12 g) per year, respectively. Biomass burning in the United States contributes less than 3% to the total global emissions

  11. Mobile source air toxics mitigation measures.

    Science.gov (United States)

    2013-10-01

    In accordance with the Federal Highway Administration (FHWA) Interim Guidance Update on Mobile Source Air Toxic Analysis in NEPA Documents (September 30, 2009), transportation projects subject to the National Environmental Policy Act (NEPA) mus...

  12. Metabolic responses of Eisenia fetida after sub-lethal exposure to organic contaminants with different toxic modes of action

    International Nuclear Information System (INIS)

    McKelvie, Jennifer R.; Wolfe, David M.; Celejewski, Magda A.; Alaee, Mehran; Simpson, Andre J.; Simpson, Myrna J.

    2011-01-01

    Nuclear magnetic resonance (NMR) - based metabolomics has the potential to identify toxic responses of contaminants within a mixture in contaminated soil. This study evaluated the metabolic response of Eisenia fetida after exposure to an array of organic compounds to determine whether contaminant-specific responses could be identified. The compounds investigated in contact tests included: two pesticides (carbaryl and chlorpyrifos), three pharmaceuticals (carbamazephine, estrone and caffeine), two persistent organohalogens (Aroclor 1254 and PBDE 209) and two industrial compounds (nonylphenol and dimethyl phthalate). Control and contaminant-exposed metabolic profiles were distinguished using principal component analysis and potential contaminant-specific biomarkers of exposure were found for several contaminants. These results suggest that NMR-based metabolomics offers considerable promise for differentiating between the different toxic modes of action (MOA) associated with sub-lethal toxicity to earthworms. - Highlights: → NMR-based earthworm metabolomic analysis of the toxic mode of action of various environmental contaminants. → Organic chemicals with different toxic modes of action resulted in varied metabolomic responses for E. fetida. → NMR-based metabolomics differentiates between the different modes of action associated with sub-lethal toxicity. - 1 H NMR metabolomics was used to identify potential biomarkers of organic contaminant exposure in Eisenia fetida earthworms.

  13. Air Contamination Quantification by FTIR with Gas Cell

    Science.gov (United States)

    Freischlag, Jason

    2017-01-01

    Air quality is of utmost importance in environmental studies and has many industrial applications such as aviators grade breathing oxygen (ABO) for pilots and breathing air for fire fighters. Contamination is a major concern for these industries as identified in MIL-PRF-27210, CGA G-4.3, CGA G-7.1, and NFPA 1989. Fourier Transform Infrared Spectroscopy (FTIR) is a powerful tool that when combined with a gas cell has tremendous potential for gas contamination analysis. Current procedures focus mostly on GC-MS for contamination quantification. Introduction of this topic will be done through a comparison of the currently used deterministic methods for gas contamination with those of FTIR gas analysis. Certification of the mentioned standards through the ISOIEC 17065 certifying body A2LA will be addressed followed by an evaluation of quality information such as the determinations of linearity and the limits of detection and quantitation. Major interferences and issues arising from the use of the FTIR for accredited work with ABO and breathing air will be covered.

  14. SEDIMENT CHEMICAL CONTAMINATION AND TOXICITY ASSOCIATED WITH A COASTAL GOLF COURSE COMPLEX.

    Science.gov (United States)

    The increasing density of golf courses represents a potential source of sediment contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to determine the concentrations of contaminants and toxicities...

  15. Toxicity and biodegradation of PCBs in contaminated sediments

    International Nuclear Information System (INIS)

    Dercova, K.; Cicmanova, J.; Lovecka, P.; Demnerova, K.; Mackova, M.; Hucko, P.; Kusnir, P.

    2006-01-01

    PCBs represent a serious ecological problem due to their low degradability, high toxicity, and strong bioaccumulation. Because of many environmental and economical problems, there are efforts to develop bio-remediation technologies for decontamination of the PCB-polluted areas. PCB were used by storage of spent nuclear fuel in nuclear power plants Jaslovske Bohunice. In the locality of the former producer of PCB - Chemko Strazske a. s. - big amount of these substances is still persisting in sediments and soil. The goal of this study was to analyze the contaminated sediments from Strazsky canal and Zemplinska Sirava water reservoir from several points of view. The study of eco-toxicity confirmed that both sediments were toxic for various tested organisms. The genotoxicity test has not proved the mutagenic effect. The subsequent step included microbiological analysis of the contaminated sediments and isolation of pure bacterial cultures capable of degrading PCBs. In order to determine the genetic potential for their biodegradability, the gene bphA1 was identified using PCR technique in their genomes. This gene codes the enzyme biphenyl-dioxygenase, which is responsible for PCB degradation. The final goal was to perform aerobic biodegradation of PCBs in the sediments. The bacteria present in both sediments are able to degrade certain low chlorinated congeners. The issue of biodiversity is still open and has to be studied to reveal the real cooperation between bacteria. (authors)

  16. Motor vehicle-related air toxics study. Final report

    International Nuclear Information System (INIS)

    1993-04-01

    Section 202 (1)(1) of the Clean Air Act (CAA), as amended (Section 206 of the Clean Air Act Amendments) (CAAA) of 1990 added paragraph (1) to Section 202 of the (CAA), directs the Environmental Protection Agency (EPA) to complete a study by May 15, 1992 of the need for, and feasibility of, controlling emissions of toxic air pollutants which are unregulated under the Act and associated with motor vehicles and motor vehicle fuels. The report has been prepared in response to Section 202 (1)(1). Specific pollutants or pollutant categories which are discussed in the report include benezene, formaldehyde, 1,3-butadiene, acetaldehyde, diesel particulate matter, gasoline particulate matter, and gasoline vapors as well as certain of the metals and motor vehicle-related pollutants identified in Section 112 of the Clean Air Act. The focus of the report is on carcinogenic risk. The study attempts to summarize what is known about motor vehicle-related air toxics and to present all significant scientific opinion on each issue

  17. Maryland air toxics regulation applicable to a natural gas compressor station

    International Nuclear Information System (INIS)

    Weidemann, H.A.; Hoffman, P.M.

    1992-01-01

    Columbia Gas Transmission Corporation submitted an air permit application to the Maryland Department of the Environment to construct a natural gas compressor station near Rutledge, Maryland. The station consists of three natural gas-fueled internal combustion reciprocating engines, each rated at 3200 horsepower. Maximum potential pollutant emissions associated with the station operation did not trigger Prevention of Significant Deterioration review or nonattainment area New Source review. However, a minor source air permit cannot be issued without addressing Maryland's toxic air regulations. Columbia initiated a detailed investigation of toxic air pollutants, including a stack test of an identical engine. Based on this information, the proposed station was subject to the toxic air regulation for acetaldehyde, acrolein, benzene, crotonaldehyde, and formaldehyde. Compliance with the toxic air regulation for crotonaldehyde was demonstrated by having an emission rate less than the threshold emission rate, specified in the regulation. The ambient air quality impact of the other four pollutants was determined using the Industrial Source Complex dispersion model and resulted in predicted concentrations below the pollutant-specific acceptable ambient level. A carcinogenic impact analysis was performed for acetaldehyde, benzene, and formaldehyde to demonstrate compliance with the accepted risk of one in one hundred thousand

  18. Assessment of the bacterial contamination of hand air dryer in washrooms

    OpenAIRE

    Alharbi, Sulaiman Ali; Salmen, Saleh Hussein; Chinnathambi, Arunachalam; Alharbi, Naiyf S.; Zayed, M.E.; Al-Johny, Bassam O.; Wainwright, Milton

    2016-01-01

    The present study was carried out, using standard techniques, to identify and count the bacterial contamination of hand air dryers, used in washrooms. Bacteria were isolated from the air flow, outlet nozzle of warm air dryers in fifteen air dryers used in these washrooms. Bacteria were found to be relatively numerous in the air flows. Bacterially contaminated air was found to be emitted whenever a warm air dryer was running, even when not being used for hand drying. Our investigation shows th...

  19. Ambient air contamination: Characterization and detection techniques

    Science.gov (United States)

    Nulton, C. P.; Silvus, H. S.

    1985-01-01

    Techniques to characterize and detect sources of ambient air contamination are described. Chemical techniques to identify indoor contaminants are outlined, they include gas chromatography, or colorimetric detection. Organics generated from indoor materials at ambient conditions and upon combustion are characterized. Piezoelectric quartz crystals are used as precision frequency determining elements in electronic oscillators.

  20. Do 16 Polycyclic Aromatic Hydrocarbons Represent PAH Air Toxicity?

    Science.gov (United States)

    Samburova, Vera; Zielinska, Barbara; Khlystov, Andrey

    2017-08-15

    Estimation of carcinogenic potency based on analysis of 16 polycyclic aromatic hydrocarbons (PAHs) ranked by U.S. Environmental Protection Agency (EPA) is the most popular approach within scientific and environmental air quality management communities. The majority of PAH monitoring projects have been focused on particle-bound PAHs, ignoring the contribution of gas-phase PAHs to the toxicity of PAH mixtures in air samples. In this study, we analyzed the results of 13 projects in which 88 PAHs in both gas and particle phases were collected from different sources (biomass burning, mining operation, and vehicle emissions), as well as in urban air. The aim was to investigate whether 16 particle-bound U.S. EPA priority PAHs adequately represented health risks of inhalation exposure to atmospheric PAH mixtures. PAH concentrations were converted to benzo(a)pyrene-equivalent (BaPeq) toxicity using the toxic equivalency factor (TEF) approach. TEFs of PAH compounds for which such data is not available were estimated using TEFs of close isomers. Total BaPeq toxicities (∑ 88 BaPeq) of gas- and particle-phase PAHs were compared with BaPeq toxicities calculated for the 16 particle-phase EPA PAH (∑ 16EPA BaPeq). The results showed that 16 EPA particle-bound PAHs underrepresented the carcinogenic potency on average by 85.6% relative to the total (gas and particle) BaPeq toxicity of 88 PAHs. Gas-phase PAHs, like methylnaphthalenes, may contribute up to 30% of ∑ 88 BaPeq. Accounting for other individual non-EPA PAHs (i.e., benzo(e)pyrene) and gas-phase PAHs (i.e., naphthalene, 1- and 2-methylnaphthalene) will make the risk assessment of PAH-containing air samples significantly more accurate.

  1. Human contamination by persistent toxic substances: the rationale to improve exposure assessment.

    Science.gov (United States)

    Porta, Miquel

    2015-10-01

    We know quite a lot about the generalized human contamination by environmental chemical agents; this statement is fully compatible with the view that most countries lack the necessary monitoring systems. We also know quite a lot about the toxic effects of environmental pollutants; this statement is fully compatible with the proposal that we need both more research and more energetic policies to decrease human contamination by such pollutants. Unsurprisingly, we know too little about the (environmental and social) causes and the etiopathogenesis (mechanisms) of the most prevalent diseases, and we will continue to miss relevant causes and mechanisms if we neglect the toxic chemicals that commonly contaminate humans, worldwide. Basic, clinical end environmental-epidemiological research on human health should more often consider integrating biomarkers of internal dose of environmental chemical pollutants. When we act in more responsible, rational, and scientific ways; when we become less dismissive towards environmental hazards; and when we thus neglect less the generalized human contamination by environmental chemical agents and their toxic effects, we will expand mechanistic biologic knowledge, and we shall as well increase the effectiveness of interventions and policies that enable the primary prevention of human diseases which cause huge amounts of economic burden and human suffering.

  2. Hydrodebridement of wounds: effectiveness in reducing wound bacterial contamination and potential for air bacterial contamination.

    Science.gov (United States)

    Bowling, Frank L; Stickings, Daryl S; Edwards-Jones, Valerie; Armstrong, David G; Boulton, Andrew Jm

    2009-05-08

    The purpose of this study was to assess the level of air contamination with bacteria after surgical hydrodebridement and to determine the effectiveness of hydro surgery on bacterial reduction of a simulated infected wound. Four porcine samples were scored then infected with a broth culture containing a variety of organisms and incubated at 37 degrees C for 24 hours. The infected samples were then debrided with the hydro surgery tool (Versajet, Smith and Nephew, Largo, Florida, USA). Samples were taken for microbiology, histology and scanning electron microscopy pre-infection, post infection and post debridement. Air bacterial contamination was evaluated before, during and after debridement by using active and passive methods; for active sampling the SAS-Super 90 air sampler was used, for passive sampling settle plates were located at set distances around the clinic room. There was no statistically significant reduction in bacterial contamination of the porcine samples post hydrodebridement. Analysis of the passive sampling showed a significant (p air whilst using hydro surgery equipment compared with a basal count of 582 CFUs/m3. During removal of the wound dressing, a significant increase was observed relative to basal counts (p air samples was still significantly raised 1 hour post-therapy. The results suggest a significant increase in bacterial air contamination both by active sampling and passive sampling. We believe that action might be taken to mitigate fallout in the settings in which this technique is used.

  3. Air toxics provisions of the Clean Air Act: Potential impacts on energy

    International Nuclear Information System (INIS)

    Hootman, H.A.; Vernet, J.E.

    1991-11-01

    This report provides an overview of the provisions of the Clean Air Act and its Amendments of 1990 that identify hazardous air pollutant (HAP) emissions and addresses their regulation by the US Environmental Protection Agency (EPA). It defines the major energy sector sources of these HAPs that would be affected by the regulations. Attention is focused on regulations that would cover coke oven emissions; chromium emission from industrial cooling towers and the electroplating process; HAP emissions from tank vessels, asbestos-related activities, organic solvent use, and ethylene oxide sterilization; and emissions of air toxics from municipal waste combustors. The possible implications of Title III regulations for the coal, natural gas, petroleum, uranium, and electric utility industries are examined. The report discusses five major databases of HAP emissions: (1) TRI (EPA's Toxic Release Inventory); (2) PISCES (Power Plant Integrated Systems: Chemical Emissions Studies developed by the Electric Power Research Institute); (3) 1985 Emissions Inventory on volatile organic compounds (used for the National Acid Precipitation Assessment Program); (4) Particulate Matter Species Manual (EPA); and (5) Toxics Emission Inventory (National Aeronautics and Space Administration). It also offers information on emission control technologies for municipal waste combustors

  4. Mapping sediment contamination and toxicity in Winter Quarters Bay, McMurdo Station, Antarctica.

    Science.gov (United States)

    Crockett, Alan B; White, Gregory J

    2003-07-01

    Winter Quarters Bay (WQB) is a small embayment located adjacent to McMurdo Station, the largest research base in Antarctica. The bay is approximately 250 m wide and long, with a maximum depth of 33 m. Historically, trash from the McMurdo Station was piled on the steep shoreline of WQB, doused with fuel and ignited. That practice has ceased, and the adjacent land area has been regraded to cover the residual waste. The bottom of WQB remains littered with drums, equipment, tanks, tires, cables, and other objects, especially the southeastern side of the bay where dumping took place. Sediments are contaminated with PCBs, metals, and hydrocarbon fuels. The objectives of this study were to map the distribution of organic contaminants in WQB, assess the toxicity of WQB sediments using a simple microbial test, and determine correlations between toxicity and contaminant levels. The study suggests that adverse ecological effects have occurred from one or more of the contaminants found in WQB but the source of the toxic impacts to bay sediments remains unknown. Whole sediment toxicity was only correlated with oil-equivalent while solvent extracts of sediments were correlated with PAHs and oil-equivalent. The authors recommend that an integrated research plan be developed that focuses on determining what additional information is needed to make informed decisions on possible remediation of WQB.

  5. [Legionella spp. contamination in indoor air: preliminary results of an Italian multicenter study].

    Science.gov (United States)

    Montagna, Maria Teresa; De Giglio, Osvalda; Napoli, Christian; Cannova, Lucia; Cristina, Maria Luisa; Deriu, Maria Grazia; Delia, Santi Antonino; Giuliano, Ada; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Mura, Ida; Pennino, Francesca; Rossini, Angelo; Tardivo, Stefano; Torre, Ida; Torregrossa, Maria Valeria; Villafrate, Maria Rosaria; Albertini, Roberto; Pasquarella, Cesira

    2014-01-01

    To propose a standardized protocol for the evaluation of Legionella contamination in air. A bathroom having a Legionella contamination in water >1,000 cfu/l was selected in 10 different healthcare facilities. Air contamination was assessed by active (Surface Air System, SAS) and passive (Index of Microbial Air, IMA) sampling for 8 hours, about 1 m away from the floor and 50 cm from the tap water. Two hundred liters of air were sampled by SAS every 12 min, after flushing water for 2 min. The IMA value was calculated as the mean value of colony forming units/16 plates exposed during sampling (2 plates/hour). Water contamination was evaluated at T0, after 4 and 8 hours, according to the standard methods. Air contamination by Legionella was found in three healthcare facilities (one with active and two with passive sampling), showing a concomitant tap water contamination (median=40,000; range 1,100-43,000 cfu/l). The remaining seven hospitals isolated Legionella spp. exclusively from water samples (median=8,000; range 1,200-70,000 cfu/l). Our data suggest that environmental Legionella contamination cannot be assessed only through the air sampling, even in the presence of an important water contamination.

  6. Vegetated Treatment Systems for Removing Contaminants Associated with Surface Water Toxicity in Agriculture and Urban Runoff.

    Science.gov (United States)

    Anderson, Brian S; Phillips, Bryn M; Voorhees, Jennifer P; Cahn, Michael

    2017-05-15

    Urban stormwater and agriculture irrigation runoff contain a complex mixture of contaminants that are often toxic to adjacent receiving waters. Runoff may be treated with simple systems designed to promote sorption of contaminants to vegetation and soils and promote infiltration. Two example systems are described: a bioswale treatment system for urban stormwater treatment, and a vegetated drainage ditch for treating agriculture irrigation runoff. Both have similar attributes that reduce contaminant loading in runoff: vegetation that results in sorption of the contaminants to the soil and plant surfaces, and water infiltration. These systems may also include the integration of granulated activated carbon as a polishing step to remove residual contaminants. Implementation of these systems in agriculture and urban watersheds requires system monitoring to verify treatment efficacy. This includes chemical monitoring for specific contaminants responsible for toxicity. The current paper emphasizes monitoring of current use pesticides since these are responsible for surface water toxicity to aquatic invertebrates.

  7. 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

  8. [Study on the groundwater petroleum contaminant remediation by air sparging].

    Science.gov (United States)

    Wang, Zhi-Qiang; Wu, Qiang; Zou, Zu-Guang; Chen, Hong; Yang, Xun-Chang; Zhao, Ji-Chu

    2007-04-01

    The groundwater petroleum contaminant remediation effect by air sparging was investigated in an oil field. The results show that the soil geological situation has great influence on the air distribution, and the shape of air distribution is not symmetrical to the air sparging (AS) well as axis. The influence distance in the left of AS well is 6 m, and only 4 m in the right. The petroleum removal rate can reach 70% in the zone with higher air saturation, but only 40% in the zone with lower air saturation, and the average petroleum removal rate reaches 60% in the influence zone for 40 days continuous air sparging. The petroleum components in groundwater were analyzed by GC/MS (gas chromatogram-mass spectrograph) before and after experiments, respectively. The results show that the petroleum removal rate has relationship with the components and their properties. The petroleum components with higher volatility are easily removed by volatilization, but those with lower volatility are difficult to remove, so a tailing effect of lingering residual contaminant exists when the air sparging technology is adopted to treat groundwater contaminated by petroleum products.

  9. Air toxics emissions from an IGCC process

    Energy Technology Data Exchange (ETDEWEB)

    Mojtahedi, W.; Norrbacka, P. [Enviropower Inc., Espoo (Finland); Hinderson, A. [Vattenfall (Sweden); Rosenberg, R.; Zilliacus, R.; Kurkela, E.; Nieminen, M. [VTT Energy, Espoo (Finland); Hoffren, H. [IVO International Oy, Vantaa (Finland)

    1996-12-01

    The so-called simplified coal gasification combined cycle process, incorporating air gasification and hot gas cleanup, promises high power generation efficiency in an environmentally acceptable manner. Increasingly more stringent environmental regulations have focused attention on the emissions of not only SO{sub 2} and NO{sub x} but also on the so-called air toxics which include a number of toxic trace elements. As result of recent amendments to the United States Clean Air Act, IGCC emissions of eleven trace elements: antimony, arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, mercury, nickel, selenium - as well as the radionuclides uranium and thorium may be regulated. Similarly, air missions standards in Europe include a limit of 0.05 mg Nm{sup 3} for mercury and cadmium and 1.0 3/Nm{sup 3} for other class I trace elements. A suitable sampling/measuring system has been developed in this project (in cooperation with Imatran Voima Oy, Electric Power Research Institute (EPRI) and Radian Cooperation) which will be used in the pressurized gasification tests. This will enable an accurate measurement of the volatilized trace element species, at high temperature and pressure, which may be found in the vapour phase. Models are being developed that can be used to determine not only the chemical equilibrium composition of gaseous, liquid and solid phases, but also possible interactions of the gaseous species with aerosol particles and surfaces, These should be used to more accurately assess the impact of the toxic trace metals emitted from the simplified IGCC system

  10. 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.

  11. Toxicity of lead-contaminated sediment to mallards

    Science.gov (United States)

    Heinz, G.H.; Hoffman, D.J.; Sileo, L.; Audet, D.J.; LeCaptain, L.J.

    1999-01-01

    Because consumption of lead-contaminated sediment has been suspected as the cause of waterfowl mortality in the Coeur d?Alene River basin in Idaho, we studied the bioavailability and toxicity of this sediment to mallards (Anas platyrhynchos). In experiment 1, one of 10 adult male mallards died when fed a pelleted commercial duck diet that contained 24% lead-contaminated sediment (with 3,400 μg/g lead in the sediment). Protoporphyrin levels in the blood increased as the percentage of lead-contaminated sediment in the diet increased. Birds fed 24% lead-contaminated sediment exhibited atrophy of the breast muscles, green staining of the feathers around the vent, viscous bile, green staining of the gizzard lining, and renal tubular intranuclear inclusion bodies. Mallards fed 24% lead-contaminated sediment had means of 6.1 μg/g of lead in the blood and 28 μg/g in the liver (wet-weight basis) and 1,660 μg/g in the feces (dry-weight basis). In experiment 2, we raised the dietary concentration of the lead-contaminated sediment to 48%, but only about 20% sediment was actually ingested due to food washing by the birds. Protoporphyrin levels were elevated in the lead-exposed birds, and all of the mallards fed 48% lead-contaminated sediment had renal tubular intranuclear inclusion bodies. The concentrations of lead in the liver were 9.1 μg/g for mallards fed 24% lead-contaminated sediment and 16 μg/g for mallards fed 48% lead-contaminated sediment. In experiment 3, four of five mallards died when fed a ground corn diet containing 24% lead-contaminated sediment (with 4,000 μg/g lead in this sample of sediment), but none died when the 24% lead-contaminated sediment was mixed into a nutritionally balanced commercial duck diet; estimated actual ingestion rates for sediment were 14% and 17% for the corn and commercial diets. Lead exposure caused elevations in protoporphyrin, and four of the five mallards fed 24% lead-contaminated sediment in a commercial diet and all five

  12. [Bacterial contamination of the indoor air in a transplant unit].

    Science.gov (United States)

    Matoušková, Ivanka; Holý, Ondřej

    2013-12-01

    For one year (August 2010 to July 2011), microbial contamination of the indoor air in the Transplant Unit of the Haemato-Oncology Clinic, Olomouc University Hospital was monitored monthly. Twenty sampling sites were singled out and a total of 240 indoor air samples were collected. An MAS-100 air sampler (Merck, GER) was used, air flow rate of 100 liters per minute, 1 minute. The measured values of indoor air temperature were stable. The relative air humidity ranged from 17% to 68%. The highest average value of microbial air contamination was found in the "staff entry room" (1170 CFU/m3). The lowest microbial air contamination (150-250 CFU/m3) was measured in the patient isolation units. The most frequently isolated bacterial strains were coagulase-negative staphylococci (94.3%), followed by Micrococcus spp. (67%) and Bacillus subtilis (11%). It can be assumed that the -source of these airborne bacterial strains are both patients and medical staff. They are classified as -opportunistic pathogens and as such can cause hospital infections among haemato-oncology patients.

  13. In utero exposure to toxic air pollutants and risk of childhood autism.

    Science.gov (United States)

    von Ehrenstein, Ondine S; Aralis, Hilary; Cockburn, Myles; Ritz, Beate

    2014-11-01

    Genetic and environmental factors are believed to contribute to the development of autism, but relatively few studies have considered potential environmental risks. Here, we examine risks for autism in children related to in utero exposure to monitored ambient air toxics from urban emissions. Among the cohort of children born in Los Angeles County, California, 1995-2006, those whose mothers resided during pregnancy in a 5-km buffer around air toxics monitoring stations were included (n = 148,722). To identify autism cases in this cohort, birth records were linked to records of children diagnosed with primary autistic disorder at the California Department of Developmental Services between 1998 and 2009 (n = 768). We calculated monthly average exposures during pregnancy for 24 air toxics selected based on suspected or known neurotoxicity or neurodevelopmental toxicity. Factor analysis helped us identify the correlational structure among air toxics, and we estimated odds ratios (ORs) for autism from logistic regression analyses. Autism risks were increased per interquartile range increase in average concentrations during pregnancy of several correlated toxics mostly loading on 1 factor, including 1,3-butadiene (OR = 1.59 [95% confidence interval = 1.18-2.15]), meta/para-xylene (1.51 [1.26-1.82]), other aromatic solvents, lead (1.49 [1.23-1.81]), perchloroethylene (1.40 [1.09-1.80]), and formaldehyde (1.34 [1.17-1.52]), adjusting for maternal age, race/ethnicity, nativity, education, insurance type, parity, child sex, and birth year. Risks for autism in children may increase following in utero exposure to ambient air toxics from urban traffic and industry emissions, as measured by community-based air-monitoring stations.

  14. The effect of plants on the degradation and toxicity of petroleum contaminants in soil: a field assessment.

    Science.gov (United States)

    Banks, M K; Schwab, P; Liu, B; Kulakow, P A; Smith, J S; Kim, R

    2003-01-01

    A field project located at the US Naval Base at Port Hueneme, California was designed to evaluate changes in contaminant concentrations and toxicity during phytoremediation. Vegetated plots were established in petroleum (diesel and heavy oil) contaminated soil and were evaluated over a two-year period. Plant species were chosen based on initial germination studies and included native California grasses. The toxicity of the impacted soil in vegetated and unvegetated plots was evaluated using Microtox, earthworm, and seed germination assays. The reduction of toxicity was affected more by contaminant aging than the establishment of plants. However, total petroleum hydrocarbon concentrations were lower by the end of the study in the vegetated plots when compared to the unvegetated soil. Although phytoremediation is an effective approach for cleaning-up of petroleum contaminated soil, a long-term management plan is required for significant reductions in contaminant concentrations.

  15. Sediment and toxic contaminant transport modeling in coastal waters

    International Nuclear Information System (INIS)

    Onishi, Yasuo; Mayer, D.W.; Argo, R.S.

    1982-01-01

    Models are presented to estimate the migration of toxic contaminants in coastal waters. Ocean current is simulated by the vertically-averaged, finite element, two-demensional model known as CAFE-I with the Galerkin weighted residual technique. The refraction of locally generated waves or swells is simulated by the wave refraction model, LO3D. Using computed current, depth, and wave characteristics, the finite element model, FETRA, simulated sediment and contaminant transport in coastal waters, estuaries and rivers. Prior to the application of these models to the Irish Sea and other coastal waters, the finite element model, FETRA, was tested to demonstrate its ability to simulate sediment and contaminant interaction, and the mechanism governing the transport, deposition, and resuspension of contaminated sediment. Several simple equations such as the unsteady, advection-diffusion equation, the equation for noncohesive-sediment load due to wind-induced waves in offshore and surf zones, and the equation for sediment-radionuclide transport simulation were solved during the preliminary testing of the model. (Kato, T.)

  16. Yellow phosphorus process to convert toxic chemicals to non-toxic products

    Science.gov (United States)

    Chang, S.G.

    1994-07-26

    The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O[sub 3], PO, PO[sub 2], etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like. 20 figs.

  17. Microbial contamination of dental unit waterlines and effect on quality of indoor air.

    Science.gov (United States)

    Kadaifciler, Duygu Göksay; Cotuk, Aysin

    2014-06-01

    The microbiological quality in dental unit waterlines (DUWLs) is considered to be important because patients and dental staff with suppressed immune systems are regularly exposed to water and aerosols generated from dental units (DUs). Opportunistic pathogens like Pseudomonas, Legionella, Candida, and Aspergillus can be present in DUWLs, while during consultations, bioaerosols can be dispersed in the air, thus resulting in effects on microbiological quality of indoor air. This present study represents microbiological air and water quality in dental offices (DOs) and also concerns the relationship between the quality of DO air and dental unit water. This study aimed to assess both the microbial quality of dental unit water and the indoor air in 20 DOs and to survey the effect on the quality of the indoor air with the existing microorganisms in dental unit water. Fourteen out of 20 (70 %) DUWLs were found to be contaminated with a high number of aerobic mesophilic heterotrophic bacteria. In terms of bacterial air contamination levels, in 90 % of DOs, a medium level (contamination was determined, while in terms of microfungal air contamination, in all DOs, a low level (contamination was determined. Potential infection or allergen agents, such as Pseudomonas, Micrococcus, Staphylococcus, Alternaria, Cladosporium, Penicillium, Aspergillus, and Paecilomyces were isolated from water and air samples. This study's determination of contamination sources and evaluation of microbial load in DOs could contribute to the development of quality control methods in the future.

  18. Heavy metal contamination in an urban stream fed by contaminated air-conditioning and stormwater discharges.

    Science.gov (United States)

    O'Sullivan, Aisling; Wicke, Daniel; Cochrane, Tom

    2012-03-01

    Urban waterways are impacted by diffuse stormwater runoff, yet other discharges can unintentionally contaminate them. The Okeover stream in Christchurch, New Zealand, receives air-conditioning discharge, while its ephemeral reach relies on untreated stormwater flow. Despite rehabilitation efforts, the ecosystem is still highly disturbed. It was assumed that stormwater was the sole contamination source to the stream although water quality data were sparse. We therefore investigated its water and sediment quality and compared the data with appropriate ecotoxicological thresholds from all water sources. Concentrations of metals (Zn, Cu and Pb) in stream baseflow, stormwater runoff, air-conditioning discharge and stream-bed sediments were quantified along with flow regimes to ascertain annual contaminant loads. Metals were analysed by ICP-MS following accredited techniques. Zn, Cu and Pb concentrations from stormflow exceeded relevant guidelines for the protection of 90% of aquatic species by 18-, 9- and 5-fold, respectively, suggesting substantial ecotoxicity potential. Sporadic copper (Cu) inputs from roof runoff exceeded these levels up to 3,200-fold at >4,000 μg L⁻¹ while Cu in baseflow from air-conditioning inputs exceeded them 5.4-fold. There was an 11-fold greater annual Cu load to the stream from air-conditioning discharge compared to stormwater runoff. Most Zn and Cu were dissolved species possibly enhancing metal bioavailability. Elevated metal concentrations were also found throughout the stream sediments. Environmental investigations revealed unsuspected contamination from air-conditioning discharge that contributed greater Cu annual loads to an urban stream compared to stormwater inputs. This discovery helped reassess treatment strategies for regaining ecological integrity in the ecosystem.

  19. Estimating risk at a Superfund site contaminated with radiological and chemical wastes

    International Nuclear Information System (INIS)

    Temeshy, A.; Liedle, J.M.; Sims, L.M.; Efird, C.R.

    1992-01-01

    This paper describes the method and results for estimating carcinogenic and noncarcinogenic effects at a Superfund site that is radiologically and chemically contaminated. Risk to receptors from disposal of waste in soil and resulting contamination of groundwater, air, surface water, and sediment is quantified. Specific risk assessment components which are addressed are the exposure assessment, toxicity assessment, and the resulting risk characterization. In the exposure assessment, potential exposure pathways are identified using waste disposal inventory information for soil and modeled information for other media. Models are used to calculate future radionuclide concentrations in groundwater, soil, surface water and air. Chemical exposure concentrations are quantified using site characterization data. Models are used to determine concentrations of chemicals in surface water and in air. Toxicity parameters used to quantify the dose-response relationship associated with the carcinogenic contaminants are slope factors and with noncarcinogenic contaminants are reference doses. In the risk characterization step, results from the exposure assessment and toxicity assessment are summarized and integrated into quantitative risk estimates for carcinogens and hazard induces for noncarcinogens. Calculated risks for carcinogenic contaminants are compared with EPA's target risk range. At WAG 6, the risk from radionuclides and chemicals for an on-WAG homesteader exceeds EPA's target risk range. Hazard indices are compared to unity for noncarcinogenic contaminants. At WAG 6, the total pathway hazard index for the on-WAG homesteader exceeds unity

  20. [Establishment of Assessment Method for Air Bacteria and Fungi Contamination].

    Science.gov (United States)

    Zhang, Hua-ling; Yao, Da-jun; Zhang, Yu; Fang, Zi-liang

    2016-03-15

    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.

  1. Toxicity assessment of chemical contaminants;transition from in vitromethods to novel in vitro methods

    Directory of Open Access Journals (Sweden)

    A.A. Farshad

    2007-04-01

    Full Text Available Exposure to occupational and environmental contaminants is a major contributor to human health problems. Despite significant achievements in the risk assessment of chemicals, the toxicological database, particularly for industrial chemicals, remains limited. Considering there areapproximately 80, 000 chemicals in commerce, and an extremely large number of chemical mixtures, in vivo testing of this large number is unachievable from ethical, economical and scientific perspectives. Therefore, increasing the number of available industrial chemicals andnew products has created a demand for alternatives to animal methods for better safety evaluation. Recent toxicity studies have demonstrated that in vitro methods are capable of rapidly providing toxicity information. In this review, current toxicity test methods for risk evaluation of industrial chemical contaminants are presented. To evaluate the potential applications of  more recent test methods developed for toxicity testing of chemical contaminants are discussed. Although  to be considered more broadly for risk assessment of human chemical exposures. In vitro methods,in vitro toxicology methods cannot exactly mimic the biodynamics of the whole body, in vitro  relationships (QSARs and physiologically based toxicokinetic (PBTK models have a potentialtest systems in combination with the knowledge of quantitative structure activity.

  2. Protection of atmospheric air against radioactive gas and aerosol contaminants

    International Nuclear Information System (INIS)

    Zykova, A.S.

    1984-01-01

    Measures for contamination protection of atmospheric air subdivided into active and passive ones, are considered. The active measures envisage: development and application of waste-free flowsheets, use of flowsheets which restrict formation of gaseous-aerosol discharges; application of highly efficient treatment facilities torage. Dispersion of radioactive substances, released with discharges to the atmosphere, using high stacks; development of the corresponding site-selection solutions and arrangement of sanitary protective zones belong to passive measures. Measures for protection of atmospheric air also include waste and air contamination monitoring. The measures described are considered as applied to NPPs

  3. Carcinogenic Air Toxics Exposure and Their Cancer-Related Health Impacts in the United States.

    Science.gov (United States)

    Zhou, Ying; Li, Chaoyang; Huijbregts, Mark A J; Mumtaz, M Moiz

    2015-01-01

    Public health protection from air pollution can be achieved more effectively by shifting from a single-pollutant approach to a multi-pollutant approach. To develop such multi-pollutant approaches, identifying which air pollutants are present most frequently is essential. This study aims to determine the frequently found carcinogenic air toxics or hazardous air pollutants (HAPs) combinations across the United States as well as to analyze the health impacts of developing cancer due to exposure to these HAPs. To identify the most commonly found carcinogenic air toxics combinations, we first identified HAPs with cancer risk greater than one in a million in more than 5% of the census tracts across the United States, based on the National-Scale Air Toxics Assessment (NATA) by the U.S. EPA for year 2005. We then calculated the frequencies of their two-component (binary), and three-component (ternary) combinations. To quantify the cancer-related health impacts, we focused on the 10 most frequently found HAPs with national average cancer risk greater than one in a million. Their cancer-related health impacts were calculated by converting lifetime cancer risk reported in NATA 2005 to years of healthy life lost or Disability-Adjusted Life Years (DALYs). We found that the most frequently found air toxics with cancer risk greater than one in a million are formaldehyde, carbon tetrachloride, acetaldehyde, and benzene. The most frequently occurring binary pairs and ternary mixtures are the various combinations of these four air toxics. Analysis of urban and rural HAPs did not reveal significant differences in the top combinations of these chemicals. The cumulative annual cancer-related health impacts of inhaling the top 10 carcinogenic air toxics included was about 1,600 DALYs in the United States or 0.6 DALYs per 100,000 people. Formaldehyde and benzene together contribute nearly 60 percent of the total cancer-related health impacts. Our study shows that although there are many

  4. Carcinogenic Air Toxics Exposure and Their Cancer-Related Health Impacts in the United States.

    Directory of Open Access Journals (Sweden)

    Ying Zhou

    Full Text Available Public health protection from air pollution can be achieved more effectively by shifting from a single-pollutant approach to a multi-pollutant approach. To develop such multi-pollutant approaches, identifying which air pollutants are present most frequently is essential. This study aims to determine the frequently found carcinogenic air toxics or hazardous air pollutants (HAPs combinations across the United States as well as to analyze the health impacts of developing cancer due to exposure to these HAPs. To identify the most commonly found carcinogenic air toxics combinations, we first identified HAPs with cancer risk greater than one in a million in more than 5% of the census tracts across the United States, based on the National-Scale Air Toxics Assessment (NATA by the U.S. EPA for year 2005. We then calculated the frequencies of their two-component (binary, and three-component (ternary combinations. To quantify the cancer-related health impacts, we focused on the 10 most frequently found HAPs with national average cancer risk greater than one in a million. Their cancer-related health impacts were calculated by converting lifetime cancer risk reported in NATA 2005 to years of healthy life lost or Disability-Adjusted Life Years (DALYs. We found that the most frequently found air toxics with cancer risk greater than one in a million are formaldehyde, carbon tetrachloride, acetaldehyde, and benzene. The most frequently occurring binary pairs and ternary mixtures are the various combinations of these four air toxics. Analysis of urban and rural HAPs did not reveal significant differences in the top combinations of these chemicals. The cumulative annual cancer-related health impacts of inhaling the top 10 carcinogenic air toxics included was about 1,600 DALYs in the United States or 0.6 DALYs per 100,000 people. Formaldehyde and benzene together contribute nearly 60 percent of the total cancer-related health impacts. Our study shows that although

  5. Risk Assessment for Toxic Air Pollutants: A Citizen's Guide

    Science.gov (United States)

    ... poisonous substances in the air that come from natural sources (for example, radon gas coming up from the ground) or from manmade sources (for example, chemical compounds given off by factory smokestacks) and can harm the environment or your health. Inhaling (or breathing) toxic air ...

  6. OPEN AIR DEMOLITION OF FACILITIES HIGHLY CONTAMINATED WITH PLUTONIUM

    International Nuclear Information System (INIS)

    LLOYD, E.R.

    2007-01-01

    The demolition of highly contaminated plutonium buildings usually is a long and expensive process that involves decontaminating the building to near free- release standards and then using conventional methods to remove the structure. It doesn't, however, have to be that way. Fluor has torn down buildings highly contaminated with plutonium without excessive decontamination. By removing the select source term and fixing the remaining contamination on the walls, ceilings, floors, and equipment surfaces; open-air demolition is not only feasible, but it can be done cheaper, better (safer), and faster. Open-air demolition techniques were used to demolish two highly contaminated buildings to slab-on-grade. These facilities on the Department of Energy's Hanford Site were located in, or very near, compounds of operating nuclear facilities that housed hundreds of people working on a daily basis. To keep the facilities operating and the personnel safe, the projects had to be creative in demolishing the structures. Several key techniques were used to control contamination and keep it within the confines of the demolition area: spraying fixatives before demolition; applying fixative and misting with a fine spray of water as the buildings were being taken down; and demolishing the buildings in a controlled and methodical manner. In addition, detailed air-dispersion modeling was done to establish necessary building and meteorological conditions and to confirm the adequacy of the proposed methods. Both demolition projects were accomplished without any spread of contamination outside the modest buffer areas established for contamination control. Furthermore, personnel exposure to radiological and physical hazards was significantly reduced by using heavy equipment rather than ''hands on'' techniques

  7. Urban land use, air toxics and public health: Assessing hazardous exposures at the neighborhood scale

    International Nuclear Information System (INIS)

    Corburn, Jason

    2007-01-01

    Land use data are increasingly understood as important indicators of potential environmental health risk in urban areas where micro-scale or neighborhood level hazard exposure data are not routinely collected. This paper aims to offer a method for estimating the distribution of air toxics in urban neighborhoods using land use information because actual air monitoring data rarely exist at this scale. Using Geographic Information System spatial modeling tools, we estimate air toxics concentrations across neighborhoods in New York City and statistically compare our model with the US Environmental Protection Agency's National Air Toxic Assessment and air monitoring data across three NYC neighborhoods. We conclude that land use data can act as a good proxy for estimating neighborhood scale air toxics, particularly in the absence of monitoring data. In addition, the paper suggests that land use data can expand the reach of environmental impact assessments that routinely exclude analyses of potential exposures to urban air toxics at the neighborhood scale

  8. Simulation of heavy metal contamination of fresh water bodies: toxic ...

    African Journals Online (AJOL)

    Michael Horsfall

    www.bioline.org.br/ja. Simulation of heavy metal contamination of fresh water bodies: toxic effects in the ... 96 hours (though sampling was done at the 48th hour). Biochemical markers of ... silver, while enhancing the bioavailability of mercury in Ceriodaphnia ..... Biochemical and molecular disorders of bilirubin metabolism.

  9. Are PAHS the Right Metric for Assessing Toxicity Related to Oils, Tars, Creosote and Similar Contaminants in Sediments?

    Science.gov (United States)

    Oils, tars, and other non-aqueous phase hydrocarbon liquids (NAPLs) are common sources of contamination in aquatic sediments, and the toxicity of such contamination has generally been attributed to component chemicals, particularly PAHs. While there is no doubt PAHs can be toxic ...

  10. Potential air contamination during CO2 angiography using a hand-held syringe: theoretical considerations and gas chromatography.

    Science.gov (United States)

    Cho, David R; Cho, Kyung J; Hawkins, Irvin F

    2006-01-01

    To assess air contamination in the hand-held syringes currently used for CO2 delivery and to determine whether there is an association between their position and the rate of air contamination. Assessment of air contamination in the syringe (20 ml) included theoretical modeling, mathematical calculation, and gas chromatography (GC). The model was used with Fick's first law to calculate the diffusion of CO2 and the amount of air contamination. For GC studies, the syringes were placed in the upright, horizontal, and inverted positions and gas samples were obtained after 5, 10, 20, 30, and 60 min. All trials with each position for each sampling time were performed five times. The amounts of air contamination with time calculated mathematically were 5-10% less than those of GC. With the diffusivity of air-CO2 at 0.1599 cm2/sec (9.594 cm2/min), air contamination was calculated to be 60% at 60 min. With GC air contamination was 13% at 5 min, 31% at 20 min, 43% at 30 min, and 68% at 60 min. There was no difference in air contamination between the different syringe positions. Air contamination occurs in hand-held syringes filled with CO2 when they are open to the ambient air. The amounts of air contamination over time are similar among syringes placed in the upright, horizontal, and inverted positions.

  11. Microbial contamination and chemical toxicity of the Rio Grande

    Directory of Open Access Journals (Sweden)

    Valles Adrian

    2004-04-01

    Full Text Available Abstract Background The Rio Grande River is the natural boundary between U.S. and Mexico from El Paso, TX to Brownsville, TX. and is one of the major water resources of the area. Agriculture, farming, maquiladora industry, domestic activities, as well as differences in disposal regulations and enforcement increase the contamination potential of water supplies along the border region. Therefore, continuous and accurate assessment of the quality of water supplies is of paramount importance. The objectives of this study were to monitor water quality of the Rio Grande and to determine if any correlations exist between fecal coliforms, E. coli, chemical toxicity as determined by Botsford's assay, H. pylori presence, and environmental parameters. Seven sites along a 112-Km segment of the Rio Grande from Sunland Park, NM to Fort Hancock, TX were sampled on a monthly basis between January 2000 and December 2002. Results The results showed great variability in the number of fecal coliforms, and E. coli on a month-to-month basis. Fecal coliforms ranged between 0–106 CFU/100 ml while E. coli ranged between 6 to > 2419 MPN. H. pylori showed positive detection for all the sites at different times. Toxicity ranged between 0 to 94% of inhibition capacity (IC. Since values above 50% are considered to be toxic, most of the sites displayed significant chemical toxicity at different times of the year. No significant correlations were observed between microbial indicators and chemical toxicity. Conclusion The results of the present study indicate that the 112-Km segment of the Rio Grande river from Sunland Park, NM to Fort Hancock, TX exceeds the standards for contact recreation water on a continuous basis. In addition, the presence of chemical toxicity in most sites along the 112-Km segment indicates that water quality is an area of concern for the bi-national region. The presence of H. pylori adds to the potential health hazards of the Rio Grande. Since no

  12. Precipitation of metals in produced water : influence on contaminant transport and toxicity

    International Nuclear Information System (INIS)

    Azetsu-Scott, K.; Wohlgeschaffen, G.; Yeats, P.; Dalziel, J.; Niven, S.; Lee, K.

    2006-01-01

    Produced water contains a number of compounds of environmental concern and is the largest volume waste stream from oil and gas production activities. Recent studies have shown that chemicals dissolved in waste water from oil platforms stunted the growth of North Sea cod and affected their breeding patterns. Scientific research is needed to identify the impact of produced water discharges on the environment as well as to identify acceptable disposal limits for produced water. This presentation provided details of a study to characterize produced water discharged within the Atlantic regions of Canada. The study included dose response biological effect studies; research on processes controlling the transport and transformation of contaminants associated with produced water discharges and the development of risk assessment models. The sample location for the study was a site near Sable Island off the coast of Nova Scotia. Chemical analysis of the produced water was conducted as well as toxicity tests. Other tests included a time-series particulate matter sedimentation test; time-series metal and toxicity analysis; time-series change in metal precipitates tests and a produced water/seawater layering experiment. Dissolved and particulate fractions were presented, and the relationship between toxicity and particulate concentrations was examined. Results of the study suggested that produced water contaminants are variable over spatial and temporal scales due to source variations and changes in discharge rates. Chemical changes occur within 24 hours of produced water being mixed with seawater and facilitate contaminant partitioning between the surface micro layer, water column and sediments. Changes in the toxicity of the produced water are correlated with the partitioning of chemical components. The impact zone may be influenced by chemical kinetics that control the distribution of potential toxic metals. Further research is needed to investigate the effects of low level

  13. Control of air toxics

    International Nuclear Information System (INIS)

    Livengood, C.D.

    1995-01-01

    For more than 10 years, Argonne National Laboratory has supported the US DOE's Flue Gas Cleanup Program objective by developing new or improved environmental controls for industries that use fossil fuels. Argonne's pollutant emissions research has ranged from experiments in the basic chemistry of pollution-control systems, through laboratory-scale process development and testing, to pilot-scale field tests of several technologies. The work on air toxics is currently divided into two components: Investigating measures to improve the removal of mercury in existing pollution-control systems applied to coal combustion; and, Developing sensors and control techniques for emissions found in the textile industry

  14. heavy metal fixation in contaminated soil using non-toxic agents

    African Journals Online (AJOL)

    USER

    2013-05-08

    May 8, 2013 ... agricultural ecosystems (Chukwuka and Omotayo,. 2008), as well as remediation of former industrial sites which have been exposed to diffuse pollution by toxic heavy metals (Finžgar et al., 2006; Belviso et al., 2010). Among the remediation technologies available for contaminated sites, in situ (in place) ...

  15. Process and apparatus for decontaminating air

    International Nuclear Information System (INIS)

    Reynolds, W.D.

    1993-01-01

    An apparatus for irradiating a contaminated air stream emanating from contaminated sources which contain mixtures of one or more volatile toxic and hazardous organic solvents or petroleum product vapors with ultraviolet wave energy below 200 nm is described comprising: a first means for passing the contaminated air stream via a tube into an enclosed empty air flow duct to allow free flow of said contaminated air stream; a second means for introducing a secondary fresh air stream into an inlet of said first means to dilute and maintain the contaminated air stream at a predetermined concentration level; a means for measuring a flow rate of said contaminated air stream; said air duct containing at least a first and second residence chambers separated by a wall divider; said divider containing at least one opening in which is mounted at least one centrally located ultraviolet wave energy source extending into said air stream to allow said contaminated air stream to pass around and in close contact with said wave energy source, wherein said contaminated air stream is irradiated by said wave energy source; an analyzer means for conducting on-line real time analysis of said diluted contaminated air stream in said first residence chamber, said analyzer means being capable of analyzing any residual contaminated mixtures in an effluent air stream from said second residence chamber; whereby said ultraviolet wave energy source functions to generate oxygen atom free radicals, other free radicals, ions, and ozone to react with the contaminated air strewn to produce unwanted acid gases, and wherein said effluent air stream containing the unwanted acid gases, being passed from said second residence chamber, can be disposed of in any manner known to the art

  16. Risk assessment of mercury contaminated sites

    International Nuclear Information System (INIS)

    Hempel, M.

    1993-01-01

    At two sites, highly contaminated with mercury, risk assessment was executed. Methods were developed to determine organomercury compounds in water, air and soil. Toxicity tests demonstrated the high toxicity of organomercury compounds compared to inorganic mercury. Besides highly toxic methylmercury, ethylmercury was found in soils close to a chemical plant in Marktredwitz. In ultrafiltration-experiments mercury showed great affinity to high molecular substances in water. Lysimeter-experiments proved, that organomercury compounds are adsorbed and transformed to inorganic and elemental mercury. (orig.) [de

  17. Potential Air Contamination During CO2 Angiography Using a Hand-Held Syringe: Theoretical Considerations and Gas Chromatography

    International Nuclear Information System (INIS)

    Cho, David R.; Cho, Kyung J.; Hawkins, Irvin F.

    2006-01-01

    Purpose. To assess air contamination in the hand-held syringes currently used for CO 2 delivery and to determine whether there is an association between their position and the rate of air contamination. Methods. Assessment of air contamination in the syringe (20 ml) included theoretical modeling, mathematical calculation, and gas chromatography (GC). The model was used with Fick's first law to calculate the diffusion of CO 2 and the amount of air contamination. For GC studies, the syringes were placed in the upright, horizontal, and inverted positions and gas samples were obtained after 5, 10, 20, 30, and 60 min. All trials with each position for each sampling time were performed five times. Results. The amounts of air contamination with time calculated mathematically were 5-10% less than those of GC. With the diffusivity of air-CO 2 at 0.1599 cm 2 /sec (9.594 cm 2 /min), air contamination was calculated to be 60% at 60 min. With GC air contamination was 13% at 5 min, 31% at 20 min, 43% at 30 min, and 68% at 60 min. There was no difference in air contamination between the different syringe positions. Conclusion. Air contamination occurs in hand-held syringes filled with CO 2 when they are open to the ambient air. The amounts of air contamination over time are similar among syringes placed in the upright, horizontal, and inverted positions

  18. Development of a suitable test method for evaluating the toxicity of contaminated soils to earthworms in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Stephenson, G.L. [Univ. of Guelph, Ontario (Canada); Scroggins, R. [Environment Canada, Gloucester, Ontario (Canada). Method Development and Application Section

    1995-12-31

    Environment Canada has embarked on a five year program to develop, standardize, and validate a battery of soil toxicity tests which can be used to assess the relative toxicity of contaminants in soils to terrestrial organisms. These tests must be applicable to soil conditions typically found in Canadian environments and the test species must be representative of the species of soil invertebrates or plants inhabiting soil ecosystems in Canada. One of the toxicity tests being developed is designed to assess the toxicity of contaminated soils to earthworms. Five of the potential test species belong to the Lumbricidae family and include the Canadian worm (Allobophora calignosa/Aporrectodea tuberculate), the European bark worm (Dendrodtilus rubidus (rubida)), the pink soil worm (Eisenia rosea), the red marsh worm (Lumbricus rubellus), and the Canadian night crawler or dew worm (Lumbricus terrestris). The sixth species, the white pot worm (Enchytraeus albidus), belongs to the Enchytraeidae family. Further assessment reduced the number of representative species to three. Most earthworm test methods have been developed to assess the toxicity of chemically-spiked artificial soils to Eisenia fetida or E. andrei. Test methods have also been developed to assess the relative toxicity of contaminated soils from hazardous waste sites. Comparative acute toxicity data for three species of earthworm exposed to a hydrocarbon contamination will be presented. Comparative toxicity data for the same three species of earthworm will also be presented using test procedures and conditions that have been modified to accommodate biological differences among the species of earthworm. Recommendations regarding test design, methods, and conditions optimal for each test species will be summarized and discussed with respect to the precision of test results.

  19. Toxicity assessment of industrial chemicals and airborne contaminants: transition from in vivo to in vitro test methods: a review.

    Science.gov (United States)

    Bakand, S; Winder, C; Khalil, C; Hayes, A

    2005-12-01

    Exposure to occupational and environmental contaminants is a major contributor to human health problems. Inhalation of gases, vapors, aerosols, and mixtures of these can cause a wide range of adverse health effects, ranging from simple irritation to systemic diseases. Despite significant achievements in the risk assessment of chemicals, the toxicological database, particularly for industrial chemicals, remains limited. Considering there are approximately 80,000 chemicals in commerce, and an extremely large number of chemical mixtures, in vivo testing of this large number is unachievable from both economical and practical perspectives. While in vitro methods are capable of rapidly providing toxicity information, regulatory agencies in general are still cautious about the replacement of whole-animal methods with new in vitro techniques. Although studying the toxic effects of inhaled chemicals is a complex subject, recent studies demonstrate that in vitro methods may have significant potential for assessing the toxicity of airborne contaminants. In this review, current toxicity test methods for risk evaluation of industrial chemicals and airborne contaminants are presented. To evaluate the potential applications of in vitro methods for studying respiratory toxicity, more recent models developed for toxicity testing of airborne contaminants are discussed.

  20. An assessment of air as a source of DNA contamination encountered when performing PCR.

    Science.gov (United States)

    Witt, Nina; Rodger, Gillian; Vandesompele, Jo; Benes, Vladimir; Zumla, Alimuddin; Rook, Graham A; Huggett, Jim F

    2009-12-01

    Sensitive molecular methods, such as the PCR, can detect low-level contamination, and careful technique is required to reduce the impact of contaminants. Yet, some assays that are designed to detect high copy-number target sequences appear to be impossible to perform without contamination, and frequently, personnel or laboratory environment are held responsible as the source. This complicates diagnostic and research analysis when using molecular methods. To investigate the air specifically as a source of contamination, which might occur during PCR setup, we exposed tubes of water to the air of a laboratory and clean hood for up to 24 h. To increase the chances of contamination, we also investigated a busy open-plan office in the same way. All of the experiments showed the presence of human and rodent DNA contamination. However, there was no accumulation of the contamination in any of the environments investigated, suggesting that the air was not the source of contamination. Even the air from a busy open-plan office was a poor source of contamination for all of the DNA sequences investigated (human, bacterial, fungal, and rodent). This demonstrates that the personnel and immediate laboratory environment are not necessarily to blame for the observed contamination.

  1. Evaluation of the Level of air Microbial Contamination in some ...

    African Journals Online (AJOL)

    The level of air microbial contamination in some teaching hospitals waste dump site in South Eastern Nigeria was evaluated using the standard microbiological techniques. Passive air sampling was performed using settle plates. The microbial load of the air around the hospitals waste dumpsite, showed high microbial load ...

  2. Current Status of Air Toxics Management and Its Strategies for Controlling Emissions in Taiwan

    Directory of Open Access Journals (Sweden)

    Wen-Tien Tsai

    2016-04-01

    Full Text Available Since the 1970s, hazardous air pollutants (HAPs, so-called air toxics, have been of great concern because they can cause serious human health effects and have adverse effects on the environment. More noticeably, some of them are known to be human carcinogens. The objective of this paper is to investigate the regulatory systems and human health effects of air toxics which have been designated by the Taiwan government under the Air Pollution Control Act. These toxic air pollutants include acutely toxic gas (i.e., ammonia, chlorine, fluorides, hydrochloric acid, hydrogen cyanide, hydrogen sulfide, nitric acid, phosphoric acid and sulfuric acid, gas containing heavy metals, and carcinogenic chemicals (including formaldehyde, vinyl chloride, asbestos and matter containing asbestos, dioxins and furans, volatile organic compounds, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls. In line with international concern about the carcinogenic risk and environmental persistence of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs and heavy metals in recent years, the current status in monitoring and reducing the emissions of PCDDs/PCDFs from stationary sources was analyzed as a case study in the present study. Furthermore, the control strategies for reducing emissions of air toxics from stationary sources in Taiwan were also addressed.

  3. Phytotoxicity of trace metals in spiked and field-contaminated soils: Linking soil-extractable metals with toxicity.

    Science.gov (United States)

    Hamels, Fanny; Malevé, Jasmina; Sonnet, Philippe; Kleja, Dan Berggren; Smolders, Erik

    2014-11-01

    Soil tests have been widely developed to predict trace metal uptake by plants. The prediction of metal toxicity, however, has rarely been tested. The present study was set up to compare 8 established soil tests for diagnosing phytotoxicity in contaminated soils. Nine soils contaminated with Zn or Cu by metal mining, smelting, or processing were collected. Uncontaminated reference soils with similar soil properties were sampled, and series of increasing contamination were created by mixing each with the corresponding soil. In addition, each reference soil was spiked with either ZnCl2 or CuCl2 at several concentrations. Total metal toxicity to barley seedling growth in the field-contaminated soils was up to 30 times lower than that in corresponding spiked soils. Total metal (aqua regia-soluble) toxicity thresholds of 50% effective concentrations (EC50) varied by factors up to 260 (Zn) or 6 (Cu) among soils. For Zn, variations in EC50 thresholds decreased as aqua regia > 0.43 M HNO3  > 0.05 M ethylenediamine tetraacetic acid (EDTA) > 1 M NH4 NO3  > cobaltihexamine > diffusive gradients in thin films (DGT) > 0.001 M CaCl2 , suggesting that the last extraction is the most robust phytotoxicity index for Zn. The EDTA extraction was the most robust for Cu-contaminated soils. The isotopically exchangeable fraction of the total soil metal in the field-contaminated soils markedly explained the lower toxicity compared with spiked soils. The isotope exchange method can be used to translate soil metal limits derived from soils spiked with metal salts to site-specific soil metal limits. © 2014 SETAC.

  4. Air toxics research in Finland

    International Nuclear Information System (INIS)

    Hahkala, M.

    1994-01-01

    Air toxics research in Finland has developed rapidly in recent years. Though they have no enormous environmental problems in Finland, the author feels that they have to increase their knowledge of more efficient energy production and control technology. Enormous emission sources are around them, but there are also huge markets for know-how and technology in the energy sector. Two Finnish national research programs will ensure the continuity of the development efforts concerning combustion technology and environmental aspects at both theoretical and practical levels

  5. Colombian legislation for air contamination control

    International Nuclear Information System (INIS)

    Hernandez S, Gildardo; Montes de Correa, Consuelo

    1999-01-01

    The most relevant legislative acts promulgated by the Colombian government for controlling atmospheric pollution are reviewed in chronological order. Special emphasis is paid to decree 948 of 1995 modified according to decree 2107 of 1995, e. The general dispositions about norms of air quality, emission levels, contaminant emissions, noise and offensive odors (chapter II), as well as, prohibitions and restrictions to emissions and noise from stationary and mobile sources (chapters III-V) furthermore, the resolutions issued so far by the ministry of the environment for regulating decree 948/95 in those aspects related to the prevention and control of atmospheric pollution are describes. Finally, the main philosophies for regulating air pollutants around the world are explained: the emissions norms, air quality norms, the emission taxes philosophy and the cost-benefit norms

  6. Carbapenem-Resistant Acinetobacter baumannii: Concomitant Contamination of Air and Environmental Surfaces.

    Science.gov (United States)

    Shimose, Luis A; Masuda, Eriko; Sfeir, Maroun; Berbel Caban, Ana; Bueno, Maria X; dePascale, Dennise; Spychala, Caressa N; Cleary, Timothy; Namias, Nicholas; Kett, Daniel H; Doi, Yohei; Munoz-Price, L Silvia

    2016-07-01

    OBJECTIVE To concomitantly determine the differential degrees of air and environmental contamination by Acinetobacter baumannii based on anatomic source of colonization and type of ICU layout (single-occupancy vs open layout). DESIGN Longitudinal prospective surveillance study of air and environmental surfaces in patient rooms. SETTING A 1,500-bed public teaching hospital in Miami, Florida. PATIENTS Consecutive A. baumannii-colonized patients admitted to our ICUs between October 2013 and February 2014. METHODS Air and environmental surfaces of the rooms of A. baumannii-colonized patients were sampled daily for up to 10 days. Pulsed-field gel electrophoresis (PFGE) was used to type and match the matching air, environmental, and clinical A. baumannii isolates. RESULTS A total of 25 A. baumannii-colonized patients were identified during the study period; 17 were colonized in the respiratory tract and 8 were colonized in the rectum. In rooms with rectally colonized patients, 38.3% of air samples were positive for A. baumannii; in rooms of patients with respiratory colonization, 13.1% of air samples were positive (P=.0001). In rooms with rectally colonized patients, 15.5% of environmental samples were positive for A. baumannii; in rooms of patients with respiratory colonization, 9.5% of environmental samples were positive (P=.02). The rates of air contamination in the open-layout and single-occupancy ICUs were 17.9% and 21.8%, respectively (P=.5). Environmental surfaces were positive in 9.5% of instances in open-layout ICUs versus 13.4% in single-occupancy ICUs (P=.09). CONCLUSIONS Air and environmental surface contaminations were significantly greater among rectally colonized patients; however, ICU layout did not influence the rate of contamination. Infect Control Hosp Epidemiol 2016;37:777-781.

  7. Petrol contaminated groundwater treatment with air-stripper in Balassagyarmat, Hungary

    International Nuclear Information System (INIS)

    Szabo, Peter; Bernath, Balazs

    2005-01-01

    Hydrocarbon contaminated groundwater is a common environmental problem in Hungary. Leakage of underground storage tanks, pipe break or illegal tapping as well as lorry accidents can be mentioned as main reasons. MEGATERRA Ltd. elaborated, adopted and tested several groundwater clean-up methods. These methods are based on detailed survey and investigation, sampling and analysis, delineation of contaminated groundwater, risk assessment, establishment of monitoring wells, pumping tests and remediation action plan. One of these methods was implemented by MEGATERRA Ltd. in Balassagyarmat, Hungary. Contamination source was a 10 m 3 vol. simple wall underground fuel-storage tank, which had been emptied. When the remediation started in April 1998, the petrol had already been accumulated on the ground water table forming a 5-7 m wide and 10-15 m long plume being expanded to SSE-NNW direction. The area of the dissolved hydrocarbon contaminated groundwater-body was 1 000 m 2 and its concentration reached up to 30-40 mg/l TPH. The free-phase hydrocarbon layer was 10 cm thick. For the remediation of contaminated groundwater MEGATERRA Ltd. applied pump and treat method, namely groundwater pumping using extraction well, skimming of free-phase hydrocarbon, stripping of the contaminated ground water in air-stripper tower and draining of the treated groundwater into a drainage ditch. In the centre of the plume we established an extraction well with 300 mm diameter in a 500 mm borehole. Peristaltic skimmer pump was used inside the extraction well to remove the free phase petrol from the ground water surface.Because of the intense volatility of the pollutant we applied aeration (stripping) technology. The extracted contaminated groundwater was cleaned in air-stripper equipment being able to eliminate efficiently the volatile pollutants from the water. The aeration tower is a compact cylindrical shaped column with 650 mm in diameter. Its height depends on the pollutant's type The

  8. Air separation of heavy metal contaminants from soil

    International Nuclear Information System (INIS)

    Nelson, M.E.; Harper, M.J.; Buckon, A.D.

    1995-01-01

    Several heavy metal separation techniques are currently being developed for soil remediation at various Department of Defense and Department of Energy (DOE) Facilities. The majority of these techniques involve a wet process using water, pH modifiers or other compounds. The US Naval Academy (USNA) has developed a dry process for heavy metal separation. The process uses air classification technology to concentrate the metal contaminant into a fraction of the soil. The advantages of this dry process are that it creates no contaminated byproduct and uses commercially available technology. The USNA process is based on using a Gayco-Reliance air classifier. Tests have been conducted with the system at the Naval Academy and the University of Nevada-Reno (UNR). The USNA tests used soil from the Nevada Test Site mixed with bismuth at a concentration of 500--1,000 ppm. The UNR tests used soil from four DOE sites mixed with uranium oxides and plutonium at an activity level of 100--700 pCi per gram. Concentration of activities and volume reduction percentages are presented for the various soils and contaminants tested

  9. High Concentrations of Organic Contaminants in Air from Ship Breaking Activities in Chittagong, Bangladesh.

    Science.gov (United States)

    Nøst, Therese H; Halse, Anne K; Randall, Scott; Borgen, Anders R; Schlabach, Martin; Paul, Alak; Rahman, Atiqur; Breivik, Knut

    2015-10-06

    The beaches on the coast of Chittagong in Bangladesh are one of the most intense ship breaking areas in the world. The aim of the study was to measure the concentrations of organic contaminants in the air in the city of Chittagong, including the surrounding ship breaking areas using passive air samplers (N = 25). The compounds detected in the highest amounts were the polycyclic aromatic hydrocarbons (PAHs) and short-chain chlorinated paraffins (SCCPs), whereas dichlorodiphenyltrichloroethanes (DDTs), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs) were several orders of magnitude lower in comparison. PCBs, PAHs, and HCB were highest at sites near the ship breaking activities, whereas DDTs and SCCPs were higher in the urban areas. Ship breaking activities likely act as atmospheric emission sources of PCBs, PAHs, and HCB, thus adding to the international emphasis on responsible recycling of ships. Concentrations of PAHs, PCBs, DDTs, HCB, and SCCPs in ambient air in Chittagong are high in comparison to those found in similar studies performed in other parts of Asia. Estimated toxic equivalent quotients indicate elevated human health risks caused by inhalation of PAHs at most sites.

  10. Minimizing the water and air impacts of unconventional energy extraction

    Science.gov (United States)

    Jackson, R. B.

    2014-12-01

    Unconventional energy generates income and, done well, can reduce air pollution compared to other fossil fuels and even water use compared to fossil fuels and nuclear energy. Alternatively, it could slow the adoption of renewables and, done poorly, release toxic chemicals into water and air. Based on research to date, some primary threats to water resources come from surface spills, wastewater disposal, and drinking-water contamination through poor well integrity. For air resources, an increase in volatile organic compounds and air toxics locally is a potential health threat, but the switch from coal to natural gas for electricity generation will reduce sulfur, nitrogen, mercury, and particulate pollution regionally. Critical needs for future research include data for 1) estimated ultimate recovery (EUR) of unconventional hydrocarbons; 2) the potential for further reductions of water requirements and chemical toxicity; 3) whether unconventional resource development alters the frequency of well-integrity failures; 4) potential contamination of surface and ground waters from drilling and spills; and 5) the consequences of greenhouse gases and air pollution on ecosystems and human health.

  11. Toxicity of lead-contaminated sediment to mute swans

    Science.gov (United States)

    Day, D.D.; Beyer, W.N.; Hoffman, D.J.; Morton, Alexandra; Sileo, L.; Audet, D.J.; Ottinger, M.A.

    2003-01-01

    weight and hematocrit and hemoglobin concentrations in swans on control (no sediment) and reference (uncontaminated) sediment diets remained unchanged. These data provide evidence that mute swans consuming environmentally relevant concentrations of Coeur d'Alene River Basin sediment developed severe sublethal lead poisoning. Furthermore, toxic effects were more pronounced when the birds were fed lead contaminated sediment combined with rice, which closely resembles the diet of swans in the wild.

  12. Evolution of the Air Toxics under the Big Sky Program

    Science.gov (United States)

    Marra, Nancy; Vanek, Diana; Hester, Carolyn; Holian, Andrij; Ward, Tony; Adams, Earle; Knuth, Randy

    2011-01-01

    As a yearlong exploration of air quality and its relation to respiratory health, the "Air Toxics Under the Big Sky" program offers opportunities for students to learn and apply science process skills through self-designed inquiry-based research projects conducted within their communities. The program follows a systematic scope and sequence…

  13. Assessment of the bacterial contamination of hand air dryer in washrooms.

    Science.gov (United States)

    Alharbi, Sulaiman Ali; Salmen, Saleh Hussein; Chinnathambi, Arunachalam; Alharbi, Naiyf S; Zayed, M E; Al-Johny, Bassam O; Wainwright, Milton

    2016-03-01

    The present study was carried out, using standard techniques, to identify and count the bacterial contamination of hand air dryers, used in washrooms. Bacteria were isolated from the air flow, outlet nozzle of warm air dryers in fifteen air dryers used in these washrooms. Bacteria were found to be relatively numerous in the air flows. Bacterially contaminated air was found to be emitted whenever a warm air dryer was running, even when not being used for hand drying. Our investigation shows that Staphylococcus haemolyticus, Micrococcus luteus, Pseudomonas alcaligenes, Bacillus cereus and Brevundimonad diminuta/vesicularis were emitted from all of the dryers sampled, with 95% showing evidence of the presence of the potential pathogen S. haemolyticus. It is concluded that hot air dryers can deposit pathogenic bacteria onto the hands and body of users. Bacteria are distributed into the general environment whenever dryers are running and could be inhaled by users and none-users alike. The results provide an evidence base for the development and enhancement of hygienic hand drying practices.

  14. Aerobic Bioremediation of PAH Contaminated Soil Results in Increased Genotoxicity and Developmental Toxicity.

    Science.gov (United States)

    Chibwe, Leah; Geier, Mitra C; Nakamura, Jun; Tanguay, Robert L; Aitken, Michael D; Simonich, Staci L Massey

    2015-12-01

    The formation of more polar and toxic polycyclic aromatic hydrocarbon (PAH) transformation products is one of the concerns associated with the bioremediation of PAH-contaminated soils. Soil contaminated with coal tar (prebioremediation) from a former manufactured gas plant (MGP) site was treated in a laboratory scale bioreactor (postbioremediation) and extracted using pressurized liquid extraction. The soil extracts were fractionated, based on polarity, and analyzed for 88 PAHs (unsubstituted, oxygenated, nitrated, and heterocyclic PAHs). The PAH concentrations in the soil tested, postbioremediation, were lower than their regulatory maximum allowable concentrations (MACs), with the exception of the higher molecular weight PAHs (BaA, BkF, BbF, BaP, and IcdP), most of which did not undergo significant biodegradation. The soil extract fractions were tested for genotoxicity using the DT40 chicken lymphocyte bioassay and developmental toxicity using the embryonic zebrafish (Danio rerio) bioassay. A statistically significant increase in genotoxicity was measured in the unfractionated soil extract, as well as in four polar soil extract fractions, postbioremediation (p toxicity was measured in one polar soil extract fraction, postbioremediation (p soil extract fractions in embryonic zebrafish, both pre- and postbioremediation. The increased toxicity measured postbioremediation is not likely due to the 88 PAHs measured in this study (including quinones), because most were not present in the toxic polar fractions and/or because their concentrations did not increase postbioremediation. However, the increased toxicity measured postbioremediation is likely due to hydroxylated and carboxylated transformation products of the 3- and 4-ring PAHs (PHE, 1MPHE, 2MPHE, PRY, BaA, and FLA) that were most degraded.

  15. Development of a male reproductive toxicity assay for evaluating the success of bioremediation

    International Nuclear Information System (INIS)

    Schrock, E.J.; Bantle, J.A.

    1995-01-01

    The Eglin Air Force Base was contaminated with JP-4 over 10 years ago. The project goal was to develop and evaluate male reproductive toxicity testing procedures and endpoints using the gametes of the South African clawed frog Xenopus laevis with particular emphasis on assessing the toxicity of contaminated soil from Eglin Air Force Base in Florida. Reproductive toxicity tests were done to evaluate several different locations within the original spill area. Specific sites were selected based on their location to the spill site. The site was evaluated before and after remediation. Before remediation, the males were exposed to the JP-4 orally for 73 days, with the contaminant injected into the food source. After remediation, the males were directly exposed to the contaminated soil samples for 60 days. The endpoints measured in both studies were: change in body weight, organ to body weight ratios, sperm counts, number of malformed sperm, and sperm motility. In both the pre and post remediation studies, there were no significant effects on body weight or organ weight data at the p ≤ 0.05 level. However, there were effects seen in sperm count and morphology. The male reproductive toxicity assay under development has given useful information in initially determining the reproductive toxicity of JP-4. Significant effects were seen in both the pre and post remediation direct exposure tests, indicating that the direct exposure route may be the most promising for future testing

  16. [Toxic fungi in Buenos Aires City and surroundings].

    Science.gov (United States)

    Romano, Gonzalo M; Iannone, Leopoldo; Novas, María V; Carmarán, Cecilia; Romero, Andrea I; López, Silvia E; Lechner, Bernardo E

    2013-01-01

    In Facultad de Ciencias Exactas y Naturales,Universidad de Buenos Aires there is a service called Servicio de Identificación de Hongos Tóxicos, directed by researchers of the Program of Medicinal Plants and Fungi Involved in Biological Degradation (PROPLAME-PRHIDEB, CONICET) that assist hospitals and other health establishments, identifying the different samples of fungi and providing information about their toxicity, so that patients can receive the correct treatment. The objective of the present study was to analyze all the cases received from 1985 to 2012. This analysis permitted the confection of a table identifying the most common toxic species. The information gathered revealed that 47% of the patients were under 18 years of age and had eaten basidiomes; the remaining 53% were adults who insisted that they were able to distinguish edible from toxic mushrooms. Chlorophyllum molybdites turned out to be the main cause of fungal intoxication in Buenos Aires, which is commonly confused with Macrolepiota procera, an edible mushroom. In the second place Amanita phalloides was registered, an agaric known to cause severe symptoms after a long period of latency (6-10 hours), and which can lead to hepatic failure even requiring a transplant to prevent severe internal injuries or even death, is not early and correctly treated.

  17. National Air Toxics Assessment - 2005, EPA Region 2 (EPA.AIR.NATA99_R2)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer is based on the model results of the 1999 National-Scale Assessment (N-SA), a part of the National Air Toxics Assessment (NATA), conducted by EPA's...

  18. National Air Toxics Assessment - 2002, EPA Region 2 (EPA.AIR.NATA99_R2)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer is based on the model results of the 1999 National-Scale Assessment (N-SA), a part of the National Air Toxics Assessment (NATA), conducted by EPA's...

  19. National Air Toxics Assessment - 1999, EPA Region 2 (EPA.AIR.NATA99_R2)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer is based on the model results of the 1999 National-Scale Assessment (N-SA), a part of the National Air Toxics Assessment (NATA), conducted by EPA's...

  20. Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites

    International Nuclear Information System (INIS)

    Sevigny, J.H.; Lintott, D.; Wrubleski, R.M.; Drury, C.R.

    1997-01-01

    The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and Microtox R toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The Microtox R toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The Microtox R toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent

  1. Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    Sevigny, J.H. [Komex Consultants Ltd., Calgary, AB (Canada); Lintott, D. [HydroQual Consultants, Inc., Calgary, AB (Canada); Wrubleski, R.M.; Drury, C.R. [Shell Canada Ltd., Calgary, AB (Canada). Calgary Research Centre

    1997-12-31

    The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and Microtox{sup R} toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The Microtox{sup R} toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The Microtox{sup R} toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent.

  2. Methods for the calculation of derived working limits for surface contamination by low-toxicity radionuclides

    International Nuclear Information System (INIS)

    Gibson, J.A.B.; Wrixon, A.D.

    1979-01-01

    Surface contamination is often measured as an indication of the general spread of radioactive contamination in a particular place. Derived working limits, (DWLs) for surface contamination provide figures against which to assess the significance of measurements. Derived working limits for surface contamination were first established for use in the nuclear energy industry. They were designed to cope with a wide range of unspecified radionuclides and were therefore based on the assumption that the contamination was due to the presence of the most hazardous radionuclides, e.g. 90 Sr, 210 Pb, 226 Ra and 239 Pu. While this assumption may still be appropriate when the radionuclide mixture is unknown, there are now many specialized uses of particular low-toxicity radionuclides in universities, hospitals and general industry. If it is known that only a particular radionuclide is present, the general DWL can be replaced by a more specific value. The methods for calculating DWLs for some of the more commonly employed low-toxicity radionuclides are described. The exposure pathways considered are (a) external radiation of the skin and inhalation of airborne material from contaminated surfaces in active areas; (b) external irradiation of the skin and ingestion from contaminated skin. Some consideration is given to the effect of the revised dose equivalent limits in the most recent recommendations of ICRP. (author)

  3. Comparison of solid-phase bioassays and ecoscores to evaluate the toxicity of contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Lors, Christine [Universite Lille Nord de France, 1bis rue Georges Lefevre, 59044 Lille Cedex (France); Ecole des Mines de Douai, MPE-GCE, 941 rue Charles-Bourseul, 59500 Douai (France); Centre National de Recherche sur les Sites et Sols Pollues, 930 Boulevard Lahure, BP 537, 59505 Douai Cedex (France); Ponge, Jean-Francois, E-mail: ponge@mnhn.f [Museum National d' Histoire Naturelle, CNRS UMR 7179, 4 Avenue du Petit-Chateau, 91800 Brunoy (France); Martinez Aldaya, Maite [Museum National d' Histoire Naturelle, CNRS UMR 7179, 4 Avenue du Petit-Chateau, 91800 Brunoy (France); Damidot, Denis [Universite Lille Nord de France, 1bis rue Georges Lefevre, 59044 Lille Cedex (France); Ecole des Mines de Douai, MPE-GCE, 941 rue Charles-Bourseul, 59500 Douai (France)

    2010-08-15

    Five bioassays (inhibition of lettuce germination and growth, earthworm mortality, inhibition of springtail population growth, avoidance by springtails) were compared, using four coke factory soils contaminated by PAHs and trace elements, before and after biotreatment. For each bioassay, several endpoints were combined in an 'ecoscore', a measure of test sensitivity. Ecoscores pooled over all tested bioassays revealed that most organisms were highly sensitive to the concentration of 3-ring PAHs. When four soils were combined, behavioural tests using the springtail Folsomia candida showed higher ecoscores, i.e. they were most sensitive to soil contamination. However, despite overall higher sensitivity of behavioural tests, which could be used for cheap and rapid assessment of soil toxicity, especially at low levels of contamination, some test endpoints were more sensitive than others, and this may differ from a soil to another, pointing to the need for a battery of bioassays when more itemized results are expected. - The avoidance test using the soil springtail Folsomia candida is globally more sensitive to PAH contamination than acute and chronic toxicity bioassays using plants and animals but a battery of tests could reveal better in detail.

  4. Comparison of solid-phase bioassays and ecoscores to evaluate the toxicity of contaminated soils

    International Nuclear Information System (INIS)

    Lors, Christine; Ponge, Jean-Francois; Martinez Aldaya, Maite; Damidot, Denis

    2010-01-01

    Five bioassays (inhibition of lettuce germination and growth, earthworm mortality, inhibition of springtail population growth, avoidance by springtails) were compared, using four coke factory soils contaminated by PAHs and trace elements, before and after biotreatment. For each bioassay, several endpoints were combined in an 'ecoscore', a measure of test sensitivity. Ecoscores pooled over all tested bioassays revealed that most organisms were highly sensitive to the concentration of 3-ring PAHs. When four soils were combined, behavioural tests using the springtail Folsomia candida showed higher ecoscores, i.e. they were most sensitive to soil contamination. However, despite overall higher sensitivity of behavioural tests, which could be used for cheap and rapid assessment of soil toxicity, especially at low levels of contamination, some test endpoints were more sensitive than others, and this may differ from a soil to another, pointing to the need for a battery of bioassays when more itemized results are expected. - The avoidance test using the soil springtail Folsomia candida is globally more sensitive to PAH contamination than acute and chronic toxicity bioassays using plants and animals but a battery of tests could reveal better in detail.

  5. Evaluation of the effects of coal fly ash amendments on the toxicity of a contaminated marine sediment

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, R.M.; Perron, M.M.; Friedman, C.L.; Suuberg, E.M.; Pennell, K.G.; Cantwell, M.G.; Pelletier, M.C.; Ho, K.T.; Serbst, J.R.; Ryba, S.A. [US EPA, Narragansett, RI (USA). Office for Research and Development

    2009-01-15

    Approaches for cleaning up contaminated sediments range from dredging to in situ treatment. In this study, we discuss the effects of amending reference and contaminated sediments with coal fly ash to reduce the bioavailability and toxicity of a field sediment contaminated with polycyclic aromatic hydrocarbons (PAHs). Six fly ashes and a coconut charcoal were evaluated in 7-d whole sediment toxicity tests with a marine amphipod (Ampelisca abdita) and mysid (Americamysis bahia). Fly ashes with high carbon content and the coconut charcoal showed proficiency at reducing toxicity. Some of the fly ashes demonstrated toxicity in the reference treatments. It is suspected that some of this toxicity is related to the presence of ammonia associated with fly ashes as a result of postoxidation treatment to reduce nitrous oxide emissions. Relatively simple methods exist to remove ammonia from fly ash before use, and fly ashes with low ammonia content are available. Fly ashes were also shown to effectively reduce overlying water concentrations of several PAHs. No evidence was seen of the release of the metals cadmium, copper, nickel, or lead from the fly ashes. A preliminary 28-d polychaete bioaccumulation study with one of the high-carbon fly ashes and a reference sediment was also performed. Although preliminary, no evidence was seen of adverse effects to worm growth or lipid content or of accumulation of PAHs or mercury from exposure to the fly ash. These data show fly ashes with high carbon content could represent viable remedial materials for reducing the bioavailability of organic contaminants in sediments.

  6. Compressed-air power tools in orthopaedic surgery: exhaust air is a potential source of contamination.

    Science.gov (United States)

    Sagi, H C; DiPasquale, Thomas; Sanders, Roy; Herscovici, Dolfi

    2002-01-01

    To determine if the exhaust from surgical compressed-air power tools contains bacteria and if the exhaust leads to contamination of sterile surfaces. Bacteriologic study of orthopaedic power tools. Level I trauma center operative theater. None. Part I. Exhaust from two sterile compact air drills was sampled directly at the exhaust port. Part II. Exhaust from the drills was directed at sterile agar plates from varying distances. The agar plates represented sterile surfaces within the operative field. Part III. Control cultures. A battery-powered drill was operated over open agar plates in similar fashion as the compressed-air drills. Agar plates left open in the operative theater served as controls to rule out atmospheric contamination. Random cultures were taken from agar plates, gloves, drills, and hoses. Incidence of positive cultures. In Part I, all filters from both compressed-air drill exhausts were culture negative ( = 0.008). In Part II, the incidence of positive cultures for air drills number one and number two was 73% and 82%, respectively. The most commonly encountered organisms were, coagulase-negative Staphylococcus, and Micrococcus species. All control cultures from agar plates, battery-powered drill, gloves, and hoses were negative ( compressed-air power tools in orthopaedic surgery may contribute to the dissemination of bacteria onto the surgical field. We do not recommend the use of compressed-air power tools that do not have a contained exhaust.

  7. Toxicity of copper to the collembolan Folsomia fimetaria in relation to the age of soil contamination.

    NARCIS (Netherlands)

    Bruus Pedersen, M.; van Gestel, C.A.M.

    2001-01-01

    The toxicity of copper to the collembolan Folsomia fimetaria L. was studied in soil incubated with copper sulfate for different periods before the introduction of collembolans, to assess the effect of aging of contamination on the toxicity of copper. Adult survival, reproduction, and juvenile size

  8. Treatment of heterogeneous mixed wastes: Enzyme degradation of cellulosic materials contaminated with hazardous organics and toxic and radioactive metals

    International Nuclear Information System (INIS)

    Vanderberg, L.A.; Foreman, T.M.; Attrep, M. Jr.; Brainard, J.R.; Sauer, N.

    1999-01-01

    The redirection and downsizing of the US Department of Energy's nuclear weapons complex requires that many facilities be decontaminated and decommissioned (D and D). At Los Alamos National Laboratory, much of the low-level radioactive, mixed, and hazardous/chemical waste volume handled by waste management operations was produced by D and D and environmental restoration activities. A combination of technologies--air stripping and biodegradation of volatile organics, enzymatic digestion of cellulosics, and metal ion extraction--was effective in treating a radiologically contaminated heterogeneous paint-stripping waste. Treatment of VOCs using a modified bioreactor avoided radioactive contamination of byproduct biomass and inhibition of biodegradation by toxic metal ions in the waste. Cellulase digestion of bulk cellulose minimized the final solid waste volume by 80%. Moreover, the residue passed TCLP for RCRA metals. Hazardous metals and radioactivity in byproduct sugar solutions were removed using polymer filtration, which employs a combination of water-soluble chelating polymers and ultrafiltration to separate and concentrate metal contaminants. Polymer filtration was used to concentrate RCRA metals and radioactivity into <5% of the original wastewater volume. Permeate solutions had no detectable radioactivity and were below RCRA-allowable discharge limits for Pb and Cr

  9. Forced-air warming design: evaluation of intake filtration, internal microbial buildup, and airborne-contamination emissions.

    Science.gov (United States)

    Reed, Mike; Kimberger, Oliver; McGovern, Paul D; Albrecht, Mark C

    2013-08-01

    Forced-air warming devices are effective for the prevention of surgical hypothermia. However, these devices intake nonsterile floor-level air, and it is unknown whether they have adequate filtration measures to prevent the internal buildup or emission of microbial contaminants. We rated the intake filtration efficiency of a popular current-generation forced-air warming device (Bair Hugger model 750, Arizant Healthcare) using a monodisperse sodium chloride aerosol in the laboratory. We further sampled 23 forced-air warming devices (same model) in daily hospital use for internal microbial buildup and airborne-contamination emissions via swabbing and particle counting. Laboratory testing found the intake filter to be 63.8% efficient. Swabbing detected microorganisms within 100% of the forced-air warming blowers sampled, with isolates of coagulase-negative staphylococci, mold, and micrococci identified. Particle counting showed 96% of forced-air warming blowers to be emitting significant levels of internally generated airborne contaminants out of the hose end. These findings highlight the need for upgraded intake filtration, preferably high-efficiency particulate air filtration (99.97% efficient), on current-generation forced-air warming devices to reduce contamination buildup and emission risks.

  10. Eco-toxicity and metal contamination of paddy soil in an e-wastes recycling area

    International Nuclear Information System (INIS)

    Zhang Junhui; Hang Min

    2009-01-01

    Paddy soil samples taken from different sites in an old primitive electronic-waste (e-waste) processing region were examined for eco-toxicity and metal contamination. Using the environmental quality standard for soils (China, Grade II) as reference, soil samples of two sites were weakly contaminated with trace metal, but site G was heavily contaminated with Cd (6.37 mg kg -1 ), and weakly contaminated with Cu (256.36 mg kg -1 ) and Zn (209.85 mg kg -1 ). Zn appeared to be strongly bound in the residual fraction (72.24-77.86%), no matter the soil was metal contaminated or not. However, more than 9% Cd and 16% Cu was present in the non-residual fraction in the metal contaminated soils than in the uncontaminated soil, especially for site G and site F. Compared with that of the control soil, the micronucleus rates of site G and site F soil treatments increased by 2.7-fold and 1.7-fold, respectively. Low germination rates were observed in site C (50%) and site G (50%) soil extraction treated rice seeds. The shortest root length (0.2377 cm) was observed in site G soil treated groups, which is only 37.57% of that of the control soil treated groups. All of the micronucleus ratio of Vicia faba root cells, rice germination rate and root length after treatment of soil extraction indicate the eco-toxicity in site F and G soils although the three indexes are different in sensitivity to soil metal contamination.

  11. Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds

    International Nuclear Information System (INIS)

    Hoess, S.; Ahlf, W.; Fahnenstich, C.; Gilberg, D.; Hollert, H.; Melbye, K.; Meller, M.; Hammers-Wirtz, M.; Heininger, P.; Neumann-Hensel, H.; Ottermanns, R.; Ratte, H.-T.

    2010-01-01

    Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity. - Sediment-contact tests require toxicity thresholds based on their variability in native sediments with low-level contamination.

  12. Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds

    Energy Technology Data Exchange (ETDEWEB)

    Hoess, S., E-mail: hoess@ecossa.d [Ecossa, Giselastr. 6, 82319 Starnberg (Germany); Institute of Biodiversity - Network (IBN), Dreikronengasse 2, 93047 Regensburg (Germany); Ahlf, W., E-mail: ahlf@tu-harburg.d [Institute of Environmental Technology and Energy Economics, Technical University Hamburg-Harburg, Eissendorfer Str. 40, 21071 Hamburg (Germany); Fahnenstich, C. [Institute of Environmental Technology and Energy Economics, Technical University Hamburg-Harburg, Eissendorfer Str. 40, 21071 Hamburg (Germany); Gilberg, D., E-mail: d-gilberg@ect.d [ECT Oekotoxikologie, Boettgerstr. 2-14, 65439 Floersheim (Germany); Hollert, H., E-mail: henner.hollert@bio5.rwth-aachen.d [Department of Ecosystem Analysis, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Melbye, K. [Dr. Fintelmann and Dr. Meyer, Mendelssohnstr. 15D, 22761 Hamburg (Germany); Meller, M., E-mail: m-meller@ecotox-consult.d [ECT Oekotoxikologie, Boettgerstr. 2-14, 65439 Floersheim (Germany); Hammers-Wirtz, M., E-mail: hammers-wirtz@gaiac.rwth-aachen.d [Research Institute for Ecosystem Analysis and Assessment (gaiac), RWTH Aachen University, Worringerweg 1, 52056 Aachen (Germany); Heininger, P., E-mail: heininger@bafg.d [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56070 Koblenz (Germany); Neumann-Hensel, H., E-mail: hensel@fintelmann-meyer.d [Dr. Fintelmann and Dr. Meyer, Mendelssohnstr. 15D, 22761 Hamburg (Germany); Ottermanns, R., E-mail: ottermanns@bio5.rwth-aachen.d [Chair for Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Ratte, H.-T., E-mail: toni.ratte@bio5.rwth-aachen.d [Chair for Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany)

    2010-09-15

    Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity. - Sediment-contact tests require toxicity thresholds based on their variability in native sediments with low-level contamination.

  13. Microbial air contamination in indoor environment of a university library.

    Science.gov (United States)

    Kalwasińska, Agnieszka; Burkowska, Aleksandra; Wilk, Iwona

    2012-01-01

    The present study was aimed at evaluating the number of bacteria and mould fungi in the indoor and outdoor environment of Toruń University Library. The sampling sites were located in the rooms serving the functions typical of libraries (i.e. in the Main Reading Room, Current Periodicals Reading Room, Collections Conservation Laboratory, Old Prints Storeroom, in rooms serving other (non-library) functions (i.e. main hall, cafeteria, and toilet) as well as outside the library building. The analyses reveal that the concentrations of bacterial as well as fungal aerosols estimated with the use of the impaction method ranged between 10(1)-10(3) CFU·m(-3), which corresponds to the concentrations normally observed in areas of this kind. Evaluation of the hygienic condition of the studied areas was based on the criteria for microbiological cleanliness in interiors submitted by the European Commission in 1993. According to this classification, the air was considered to be heavily or moderately contaminated with bacteria, while the air contamination with mould fungi was described as low or moderate. The air in the Old Prints Storeroom was considered the least contaminated with microbial aerosol.

  14. Bioavailability and toxicity of metals from a contaminated sediment by acid mine drainage: linking exposure-response relationships of the freshwater bivalve Corbicula fluminea to contaminated sediment.

    Science.gov (United States)

    Sarmiento, Aguasanta M; Bonnail, Estefanía; Nieto, José Miguel; DelValls, Ángel

    2016-11-01

    Streams and rivers strongly affected by acid mine drainage (AMD) have legal vacuum in terms of assessing the water toxicity, since the use of conventional environmental quality biomarkers is not possible due to the absence of macroinvertebrate organisms. The Asian clam Corbicula fluminea has been widely used as a biomonitor of metal contamination by AMD in freshwater systems. However, these clams are considered an invasive species in Spain and the transplantation in the field study is not allowed by the Environmental Protection Agency. To evaluate the use of the freshwater bivalve C. fluminea as a potential biomonitor for sediments contaminated by AMD, the metal bioavailability and toxicity were investigated in laboratory by exposure of clams to polluted sediments for 14 days. The studied sediments were classified as slightly contaminated with As, Cr, and Ni; moderately contaminated with Co; considerably contaminated with Pb; and heavily contaminated with Cd, Zn, and specially Cu, being reported as very toxic to Microtox. On the fourth day of the exposure, the clams exhibited an increase in concentration of Ga, Ba, Sb, and Bi (more than 100 %), followed by Co, Ni, and Pb (more than 60 %). After the fourth day, a decrease in concentration was observed for almost all metals studied except Ni. An allometric function was used to determine the relationship between the increases in metal concentration in soft tissue and the increasing bioavailable metal concentrations in sediments.

  15. Contamination of hospital compressed air with nitric oxide: unwitting replacement therapy.

    Science.gov (United States)

    Pinsky, M R; Genc, F; Lee, K H; Delgado, E

    1997-06-01

    Inhaled nitric oxide (NO) at levels between 5 and 80 ppm has been used experimentally to treat a variety of conditions. NO also is a common environmental air pollutant in industrial regions. As compressed hospital air is drawn from the local environment, we speculated that it may contain NO contamination, which, if present, would provide unwitting inhaled NO therapy to all subjects respiring this compressed gas. NO levels were measured twice daily from ambient hospital air and compressed gas sources driving positive pressure ventilation from two adjacent hospitals and compared with NO levels reported daily by local Environmental Protection Agency sources. An NO chemiluminescence analyzer (Sievers 270B; Boulder, Colo) sensitive to > or =2 parts per billion was used to measure NO levels in ambient air and compressed gas. NO levels in ambient air and hospital compressed air covaried from day to day, and absolute levels of NO differed between hospitals with the difference never exceeding 1.4 ppm (range, 0 to 1.4 ppm; median, 0.07 ppm). The hospital with the highest usage level of compressed air had the highest levels of NO, which approximated ambient levels of NO. NO levels were lowest on weekends in both hospitals. We also documented inadvertent NO contamination in one hospital occurring over 5 days, which corresponded to welding activity near the intake port for fresh gas. This contamination resulted in system-wide NO levels of 5 to 8 ppm. Hospital compressed air contains highly variable levels of NO that tend to covary with ambient NO levels and to be highest when the rate of usage is high enough to preclude natural degradation of NO in 21% oxygen. Assuming that inhaled NO may alter gas exchange, pulmonary hemodynamics, and outcome from acute lung injury, the role of unwitting variable NO of hospital compressed air needs to be evaluated.

  16. Toxic C17-Sphinganine Analogue Mycotoxin, Contaminating Tunisian Mussels, Causes Flaccid Paralysis in Rodents

    Directory of Open Access Journals (Sweden)

    Riadh Marrouchi

    2013-11-01

    Full Text Available Severe toxicity was detected in mussels from Bizerte Lagoon (Northern Tunisia using routine mouse bioassays for detecting diarrheic and paralytic toxins not associated to classical phytoplankton blooming. The atypical toxicity was characterized by rapid mouse death. The aim of the present work was to understand the basis of such toxicity. Bioassay-guided chromatographic separation and mass spectrometry were used to detect and characterize the fraction responsible for mussels’ toxicity. Only a C17-sphinganine analog mycotoxin (C17-SAMT, with a molecular mass of 287.289 Da, was found in contaminated shellfish. The doses of C17-SAMT that were lethal to 50% of mice were 750 and 150 μg/kg following intraperitoneal and intracerebroventricular injections, respectively, and 900 μg/kg following oral administration. The macroscopic general aspect of cultures and the morphological characteristics of the strains isolated from mussels revealed that the toxicity episodes were associated to the presence of marine microfungi (Fusarium sp., Aspergillus sp. and Trichoderma sp. in contaminated samples. The major in vivo effect of C17-SAMT on the mouse neuromuscular system was a dose- and time-dependent decrease of compound muscle action potential amplitude and an increased excitability threshold. In vitro, C17-SAMT caused a dose- and time-dependent block of directly- and indirectly-elicited isometric contraction of isolated mouse hemidiaphragms.

  17. Excretory nitrogen metabolism and defence against ammonia toxicity in air-breathing fishes.

    Science.gov (United States)

    Chew, S F; Ip, Y K

    2014-03-01

    With the development of air-breathing capabilities, some fishes can emerge from water, make excursions onto land or even burrow into mud during droughts. Air-breathing fishes have modified gill morphology and morphometry and accessory breathing organs, which would tend to reduce branchial ammonia excretion. As ammonia is toxic, air-breathing fishes, especially amphibious ones, are equipped with various strategies to ameliorate ammonia toxicity during emersion or ammonia exposure. These strategies can be categorized into (1) enhancement of ammonia excretion and reduction of ammonia entry, (2) conversion of ammonia to a less toxic product for accumulation and subsequent excretion, (3) reduction of ammonia production and avoidance of ammonia accumulation and (4) tolerance of ammonia at cellular and tissue levels. Active ammonia excretion, operating in conjunction with lowering of ambient pH and reduction in branchial and cutaneous NH₃ permeability, is theoretically the most effective strategy to maintain low internal ammonia concentrations. NH₃ volatilization involves the alkalization of certain epithelial surfaces and requires mechanisms to prevent NH₃ back flux. Urea synthesis is an energy-intensive process and hence uncommon among air-breathing teleosts. Aestivating African lungfishes detoxify ammonia to urea and the accumulated urea is excreted following arousal. Reduction in ammonia production is achieved in some air-breathing fishes through suppression of amino acid catabolism and proteolysis, or through partial amino acid catabolism leading to alanine formation. Others can slow down ammonia accumulation through increased glutamine synthesis in the liver and muscle. Yet, some others develop high tolerance of ammonia at cellular and tissue levels, including tissues in the brain. In summary, the responses of air-breathing fishes to ameliorate ammonia toxicity are many and varied, determined by the behaviour of the species and the nature of the environment in

  18. Air monitoring data reveal previously unknown contamination at radioactive waste disposal area, Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    Kraig, D.H.; Conrad, R.C.

    2000-01-01

    Air monitoring at Area G, the low-level radioactive waste disposal area at Los Alamos National Laboratory, revealed increased air concentrations of 239 Pu and 241 Am at one location along the north boundary. This air monitoring location is a couple of meters north of a dirt road used to access the easternmost part of Area G. Air concentrations of 238 Pu were essentially unaffected which was puzzling because both 238 Pu and 239 Pu are present in the local, slightly contaminated soils. Air concentrations of these radionuclides increased about a factor of ten in early 1995 and remained at those levels until the first quarter of 1996. During the spring of 1996 air concentrations again increased by a factor of about ten. No other radionuclides were elevated, and no other Area G stations showed elevations of these radionuclides. After several formal meetings did not provide an adequate explanation for the elevations, a gamma-survey was performed and showed a small area of significant contamination just south of the monitor location. We found that in February 1995, a trench for a water line had been dug within a meter or so of the air stations. Then, during early 1996, the dirt road was rerouted such that its new path was directly over the unknown contamination. It appears that the trenching brought contaminated material to the surface and caused the firs rise in air concentrations and then the rerouting of the road over the contamination caused the second rise, during 1996. We also found that during 1976 and 1977 contaminated soils from the clean-up of an old processing facility had been spread over the filled pits in the vicinity of the air monitors. These soils, which were probably the source of the air contamination, were very low in 238 Pu which explains why we saw very little 238 Pu in the increased air concentrations. A layer of gravel and sand was spread over the contaminated area. Although air concentrations of 239 Pu and 241 Am dropped considerably, they have

  19. Air Contamination by Mercury, Emissions and Transformations-a Review.

    Science.gov (United States)

    Gworek, Barbara; Dmuchowski, Wojciech; Baczewska, Aneta H; Brągoszewska, Paulina; Bemowska-Kałabun, Olga; Wrzosek-Jakubowska, Justyna

    2017-01-01

    The present and future air contamination by mercury is and will continue to be a serious risk for human health. This publication presents a review of the literature dealing with the issues related to air contamination by mercury and its transformations as well as its natural and anthropogenic emissions. The assessment of mercury emissions into the air poses serious methodological problems. It is particularly difficult to distinguish between natural and anthropogenic emissions and re-emissions from lands and oceans, including past emissions. At present, the largest emission sources include fuel combustion, mainly that of coal, and "artisanal and small-scale gold mining" (ASGM). The distinctly highest emissions can be found in South and South-East Asia, accounting for 45% of the global emissions. The emissions of natural origin and re-emissions are estimated at 45-66% of the global emissions, with the largest part of emissions originating in the oceans. Forecasts on the future emission levels are not unambiguous; however, most forecasts do not provide for reductions in emissions. Ninety-five percent of mercury occurring in the air is Hg 0 -GEM, and its residence time in the air is estimated at 6 to 18 months. The residence times of its Hg II -GOM and that in Hg p -TPM are estimated at hours and days. The highest mercury concentrations in the air can be found in the areas of mercury mines and those of ASGM. Since 1980 when it reached its maximum, the global background mercury concentration in the air has remained at a relatively constant level.

  20. Grandfather regulations, new source bias, and state air toxics regulations

    International Nuclear Information System (INIS)

    Levinson, Arik

    1999-01-01

    This paper uses plant-level data from the Census of Manufactures and the variation in toxic air pollution regulations across states to measure the effects of laws that are more stringent for new sources of pollution than for existing sources (so-called 'grandfather' regulations). Of particular interest is the resulting 'new source bias' and its effects on capital vintage and investment. Two industries are examined: commercial printing, which has a local product market; and paint manufacturing, which has a more national market. In general, there seem to be no statistically significant differences in capital vintage or investment between plants in states that grandfather new sources of pollution, plants in states that have no air toxics regulations, and plants in states that regulate both new and existing sources

  1. Breathless: Schools, Air Toxics, and Environmental Justice in California

    OpenAIRE

    2005-01-01

    Recent legislation on both federal and state levels has placed the intersection between children’s health and environmental justice on the forefront of public policy debate. This study looks at the intersection of air quality, children’s health, and school performance in the context of environmental equity in California. Information from the U.S. EPA’s National Air Toxics Assessment (NATA) is used to calculate a respiratory hazard ratio for each of California’s census tracts. These ratios ar...

  2. Microbial air quality and bacterial surface contamination in ambulances during patient services.

    Science.gov (United States)

    Luksamijarulkul, Pipat; Pipitsangjan, Sirikun

    2015-03-01

    We sought to assess microbial air quality and bacterial surface contamination on medical instruments and the surrounding areas among 30 ambulance runs during service. We performed a cross-sectional study of 106 air samples collected from 30 ambulances before patient services and 212 air samples collected during patient services to assess the bacterial and fungal counts at the two time points. Additionally, 226 surface swab samples were collected from medical instrument surfaces and the surrounding areas before and after ambulance runs. Groups or genus of isolated bacteria and fungi were preliminarily identified by Gram's stain and lactophenol cotton blue. Data were analyzed using descriptive statistics, t-test, and Pearson's correlation coefficient with a p-value of less than 0.050 considered significant. The mean and standard deviation of bacterial and fungal counts at the start of ambulance runs were 318±485cfu/m(3) and 522±581cfu/m(3), respectively. Bacterial counts during patient services were 468±607cfu/m(3) and fungal counts were 656±612cfu/m(3). Mean bacterial and fungal counts during patient services were significantly higher than those at the start of ambulance runs, p=0.005 and p=0.030, respectively. For surface contamination, the overall bacterial counts before and after patient services were 0.8±0.7cfu/cm(2) and 1.3±1.1cfu/cm(2), respectively (pair samples and bacterial counts on medical instruments and allocated areas. This study revealed high microbial contamination (bacterial and fungal) in ambulance air during services and higher bacterial contamination on medical instrument surfaces and allocated areas after ambulance services compared to the start of ambulance runs. Additionally, bacterial and fungal counts in ambulance air showed a significantly positive correlation with the bacterial surface contamination on medical instruments and allocated areas. Further studies should be conducted to determine the optimal intervention to reduce

  3. Sources of indoor air contamination on the ground floor of a high-rise commercial building

    International Nuclear Information System (INIS)

    Nayebzadeh, A.; Cragg-Elkouh, S.; Rancy, R.; Dufresne, A.

    1999-01-01

    Indoor air quality is a subject of growing concern in the developed world. Many sources of indoor air contamination in commercial and office buildings are recognised and have been investigated. In addition to the usual internal sources of air contaminants, other external sources from attached facilities can find their way into the building. This report presents the results of an indoor air quality survey in a high-rise office building which demonstrated an obvious seasonal change in regard to the concentrations of carbon dioxide (CO 2 ), nitric oxide (NO) and nitrogen dioxide (NO 2 ). Furthermore, a complementary survey in the same building was carried out to identify the relevant sources of air contamination in the building and the results indicated that an attached train station and the nearby street traffic had a significant impact on indoor air quality. (author)

  4. Multiple inorganic toxic substances contaminating the groundwater of Myingyan Township, Myanmar: Arsenic, manganese, fluoride, iron, and uranium

    Energy Technology Data Exchange (ETDEWEB)

    Bacquart, Thomas [Better Life Laboratories, Calais, VT (United States); Frisbie, Seth [Better Life Laboratories, Calais, VT (United States); Department of Chemistry and Biochemistry, Norwich University, Northfield, VT (United States); Mitchell, Erika [Better Life Laboratories, Calais, VT (United States); Grigg, Laurie [Department of Earth and Environmental Science, Norwich University, Northfield, VT (United States); Cole, Christopher [Department of Chemistry and Biochemistry, Norwich University, Northfield, VT (United States); Small, Colleen [Vermont Department of Health Laboratory, Burlington, VT (United States); Sarkar, Bibudhendra, E-mail: bsarkar@sickkids.ca [Department of Molecular Structure and Function, The Research Institute of The Hospital for Sick Children, University of Toronto, Toronto, Ontario (Canada); Department of Biochemistry, University of Toronto, Toronto, Ontario (Canada)

    2015-06-01

    In South Asia, the technological and societal shift from drinking surface water to groundwater has resulted in a great reduction of acute diseases due to water borne pathogens. However, arsenic and other naturally occurring inorganic toxic substances present in groundwater in the region have been linked to a variety of chronic diseases, including cancers, heart disease, and neurological problems. Due to the highly specific symptoms of chronic arsenic poisoning, arsenic was the first inorganic toxic substance to be noticed at unsafe levels in the groundwater of West Bengal, India and Bangladesh. Subsequently, other inorganic toxic substances, including manganese, uranium, and fluoride have been found at unsafe levels in groundwater in South Asia. While numerous drinking water wells throughout Myanmar have been tested for arsenic, relatively little is known about the concentrations of other inorganic toxic substances in Myanmar groundwater. In this study, we analyzed samples from 18 drinking water wells (12 in Myingyan City and 6 in nearby Tha Pyay Thar Village) and 2 locations in the Ayeyarwaddy River for arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. Concentrations of arsenic, manganese, fluoride, iron, or uranium exceeded health-based reference values in most wells. In addition, any given well usually contained more than one toxic substance at unsafe concentrations. While water testing and well sharing could reduce health risks, none of the wells sampled provide water that is entirely safe with respect to inorganic toxic substances. It is imperative that users of these wells, and users of other wells that have not been tested for multiple inorganic toxic substances throughout the region, be informed of the need for drinking water testing and the health consequences of drinking water contaminated with inorganic toxic

  5. Multiple inorganic toxic substances contaminating the groundwater of Myingyan Township, Myanmar: Arsenic, manganese, fluoride, iron, and uranium

    International Nuclear Information System (INIS)

    Bacquart, Thomas; Frisbie, Seth; Mitchell, Erika; Grigg, Laurie; Cole, Christopher; Small, Colleen; Sarkar, Bibudhendra

    2015-01-01

    In South Asia, the technological and societal shift from drinking surface water to groundwater has resulted in a great reduction of acute diseases due to water borne pathogens. However, arsenic and other naturally occurring inorganic toxic substances present in groundwater in the region have been linked to a variety of chronic diseases, including cancers, heart disease, and neurological problems. Due to the highly specific symptoms of chronic arsenic poisoning, arsenic was the first inorganic toxic substance to be noticed at unsafe levels in the groundwater of West Bengal, India and Bangladesh. Subsequently, other inorganic toxic substances, including manganese, uranium, and fluoride have been found at unsafe levels in groundwater in South Asia. While numerous drinking water wells throughout Myanmar have been tested for arsenic, relatively little is known about the concentrations of other inorganic toxic substances in Myanmar groundwater. In this study, we analyzed samples from 18 drinking water wells (12 in Myingyan City and 6 in nearby Tha Pyay Thar Village) and 2 locations in the Ayeyarwaddy River for arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. Concentrations of arsenic, manganese, fluoride, iron, or uranium exceeded health-based reference values in most wells. In addition, any given well usually contained more than one toxic substance at unsafe concentrations. While water testing and well sharing could reduce health risks, none of the wells sampled provide water that is entirely safe with respect to inorganic toxic substances. It is imperative that users of these wells, and users of other wells that have not been tested for multiple inorganic toxic substances throughout the region, be informed of the need for drinking water testing and the health consequences of drinking water contaminated with inorganic toxic

  6. Assessment of sediment contamination at Great Lakes Areas of Concern: the ARCS Program Toxicity-Chemistry Work Group strategy

    Science.gov (United States)

    Ross, P.E.; Burton, G.A.; Crecelius, E.A.; Filkins, J. C.; Giesy, J.P.; Ingersoll, C.G.; Landrum, P.F.; Mac, M.J.; Murphy, T.J.; Rathbun, J. E.; Smith, V. E.; Tatem, H. E.; Taylor, R.W.

    1992-01-01

    In response to a mandate in Section 118(c)(3) of the Water Quality Act of 1987, a program called Assessment and Remediation of Contaminated Sediments (ARCS) was established. Four technical work groups were formed. This paper details the research strategy of the Toxicity-Chemistry Work Group.The Work Group's general objectives are to develop survey methods and to map the degree of contamination and toxicity in bottom sediments at three study areas, which will serve as guidance for future surveys at other locations. A related objective is to use the data base that will be generated to calculate sediment quality concentrations by several methods. The information needed to achieve these goals will be collected in a series of field surveys at three areas: Saginaw Bay (MI), Grand Calumet River (IN), and Buffalo River (NY). Assessments of the extent of contamination and potential adverse effects of contaminants in sediment at each of these locations will be conducted by collecting samples for physical characterization, toxicity testing, mutagenicity testing, chemical analyses, and fish bioaccumulation assays. Fish populations will be assessed for tumors and external abnormalities, and benthic community structure will be analyzed. A mapping approach will use low-cost indicator parameters at a large number of stations, and will extrapolate by correlation from traditional chemical and biological studies at a smaller number of locations. Sediment toxicity testing includes elutriate, pore water and whole sediment bioassays in a three-tiered framework. In addition to the regular series of toxicity tests at primary mater stations, some stations are selected for a more extensive suite of tests.

  7. Development of Radioactive Substance Contamination Diffusion Preventive Equipment for a Hot cell

    International Nuclear Information System (INIS)

    Choo, Yong Sun; Kim, Do Sik; Baik, Seung Je; Yoo, Byung Ok; Kim, Ki Ha; Lee, Eun Pyo; Ahn, Sang Bok; Ryu, Woo Seok

    2009-01-01

    The hot cell of irradiated materials examination facility (IMEF), which has been operating since 1996, is generally contaminated by the radioactive nuclides of irradiated nuclear fuels and structural steels like Cs-137, Co-60, Co-134 and Ru-106. Especially Cs-137 is a main contaminated radioactive isotope which is easily moved here and there due to air flow in the hot cell, water-soluble, extremely toxic, and has a half-life of 30.23 years. To repair or fix the abnormal function of test apparatus installed in the hot cell, the maintenance door, so called a rear door and located at an intervention area, is opened to enter the hot cell inside. In a moment of opening the maintenance door, dirty air diffusion from the hot cell to an intervention area could be occurred in spite of increasing the rpm of exhaust fan to maintain much low under pressure, but an adjacent area to a maintenance door, i.e. intervention area, is very severely contaminated due to the unpredictable air flow. In this paper, the development of the radioactive substance contamination diffusion preventive equipment for a hot cell is studied to prevent dirty and toxic gaseous radioactive nuclides diffusion from a hot cell and installed at an intervention area of IMEF

  8. Notification: Background Investigation Services EPA’s Efforts to Incorporate Environmental Justice Into Clean Air Act Inspections for Air Toxics

    Science.gov (United States)

    Project #OPE-FY14-0017, March 7, 2014. The OIG plans to begin the preliminary research phase of an evaluation of the EPA's efforts to incorporate environmental justice into Clean Air Act (CAA) inspections for air toxics.

  9. Race, deprivation, and immigrant isolation: The spatial demography of air-toxic clusters in the continental United States.

    Science.gov (United States)

    Liévanos, Raoul S

    2015-11-01

    This article contributes to environmental inequality outcomes research on the spatial and demographic factors associated with cumulative air-toxic health risks at multiple geographic scales across the United States. It employs a rigorous spatial cluster analysis of census tract-level 2005 estimated lifetime cancer risk (LCR) of ambient air-toxic emissions from stationary (e.g., facility) and mobile (e.g., vehicular) sources to locate spatial clusters of air-toxic LCR risk in the continental United States. It then tests intersectional environmental inequality hypotheses on the predictors of tract presence in air-toxic LCR clusters with tract-level principal component factor measures of economic deprivation by race and immigrant status. Logistic regression analyses show that net of controls, isolated Latino immigrant-economic deprivation is the strongest positive demographic predictor of tract presence in air-toxic LCR clusters, followed by black-economic deprivation and isolated Asian/Pacific Islander immigrant-economic deprivation. Findings suggest scholarly and practical implications for future research, advocacy, and policy. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Addition of contaminant bioavailability and species susceptibility to a sediment toxicity assessment: Application in an urban stream in China

    International Nuclear Information System (INIS)

    Li, Huizhen; Sun, Baoquan; Chen, Xin; Lydy, Michael J.; You, Jing

    2013-01-01

    Sediments collected from an urban creek in China exhibited high acute toxicity to Hyalella azteca with 81.3% of sediments being toxic. A toxic unit (TU) estimation demonstrated that the pyrethroid, cypermethrin, was the major contributor to toxicity. The traditional TU approach, however, overestimated the toxicity. Reduced bioavailability of sediment-associated cypermethrin due to sequestration explained the overestimation. Additionally, antagonism among multiple contaminants and species susceptibility to various contaminants also contributed to the unexpectedly low toxicity to H. azteca. Bioavailable TUs derived from the bioavailability-based approaches, Tenax extraction and matrix-solid phase microextraction (matrix-SPME), showed better correlations with the noted toxicity compared to traditional TUs. As the first successful attempt to use matrix-SPME for estimating toxicity caused by emerging insecticides in field sediment, the present study found freely dissolved cypermethrin concentrations significantly improved the prediction of sediment toxicity to H. azteca compared to organic carbon normalized and Tenax extractable concentrations. Highlights: •Over 80% sediments from an urban stream in China were acutely toxic to H. azteca. •Toxic unit analysis showed cypermethrin was the major contributor to toxicity. •The traditional toxic unit approach overestimated sediment toxicity. •Reduced bioavailability was the reason for overestimating sediment toxicity. •Freely dissolved cypermethrin concentrations greatly improved toxicity prediction. -- Field sediment toxicity caused by current-use pesticides could be more accurately evaluated by incorporating bioavailability measurements into the toxic unit analysis

  11. Particulate Air Contamination in Puerto Rico: A Student Involvement Project.

    Science.gov (United States)

    Eckert, Richard R.

    1979-01-01

    Describes a research project undertaken by physics undergraduate students to monitor particulate air contamination in Ponce, Puerto Rico, and to determine the meteorological factors which contribute to it. (GA)

  12. Microbial contamination of the air at the wastewater treatment plant

    Directory of Open Access Journals (Sweden)

    Monika Vítězová

    2012-01-01

    Full Text Available Wastewater treatment plants (WWTPs primarily serve to protect the environment. Their task is to clean waste water from the agglomerations. On the other hand wastewater treatment plants can also negatively affect the environment in their neighbourhood. These include emissions of odour and microorganisms. This article discusses the microbial contamination of the air, called bioaerosols in selected wastewater treatment plant for 18 000 p.e. From results of the work is evident that the largest group of microorganisms in the monitored air were psychrophilic and mesophilic bacteria and microscopic fungi. The number of psychrophilic bacteria ranged from 14 to 12 000 CFU/m3 (colony forming units in 1 m3, the number of mesophilic bacteria varied in the range from 20 to 18 500 CFU/m3 and the fungi from 25 to 32 000 CFU/m3 in the air. The amount of actinomycetes ranged from 1 to 1 030 CFU/m3 and faecal coliform bacteria from 0 to 2 500 CFU/m3. Furthermore, it was confirmed that the highest air contamination was around the activation tank, area for dewatered sludge and around the building of mechanical cleaning, depending on the season. The density of studied microorganisms correlated with air temperature.

  13. Air suctioning during colon biopsy forceps removal reduces bacterial air contamination in the endoscopy suite.

    Science.gov (United States)

    Vavricka, S R; Tutuian, R; Imhof, A; Wildi, S; Gubler, C; Fruehauf, H; Ruef, C; Schoepfer, A M; Fried, M

    2010-09-01

    Bacterial contamination of endoscopy suites is of concern; however studies evaluating bacterial aerosols are lacking. We aimed to determine the effectiveness of air suctioning during removal of biopsy forceps in reducing bacterial air contamination. This was a prospective single-blinded trial involving 50 patients who were undergoing elective nontherapeutic colonoscopy. During colonoscopy, endoscopists removed the biopsy forceps first without and then with suctioning following contact with the sigmoid mucosa. A total of 50 L of air was collected continuously for 30 seconds at 30-cm distance from the biopsy channel valve of the colonoscope, with time starting at forceps removal. Airborne bacteria were collected by an impactor air sampler (MAS-100). Standard Petri dishes with CNA blood agar were used to culture Gram-positive bacteria. Main outcome measure was the bacterial load in endoscopy room air. At the beginning and end of the daily colonoscopy program, the median (and interquartile [IQR] range) bioaerosol burden was 4 colony forming units (CFU)/m (3) (IQR 3 - 6) and 16 CFU/m (3) (IQR 13 - 18), respectively. Air suctioning during removal of the biopsy forceps reduced the bioaerosol burden from a median of 14 CFU/m (3) (IQR 11 - 29) to a median of 7 CFU/m (3) (IQR 4 - 16) ( P = 0.0001). Predominantly enterococci were identified on the agar plates. The bacterial aerosol burden during handling of biopsy forceps can be reduced by applying air suction while removing the forceps. This simple method may reduce transmission of infectious agents during gastrointestinal endoscopies. Copyright Georg Thieme Verlag KG Stuttgart . New York.

  14. Toxic fluoride and arsenic contaminated groundwater in the Lahore and Kasur districts, Punjab, Pakistan and possible contaminant sources

    International Nuclear Information System (INIS)

    Farooqi, Abida; Masuda, Harue; Firdous, Nousheen

    2007-01-01

    The present study is the first attempt to put forward possible sources of As, F - and SO 4 2- contaminated groundwater in the Kalalanwala area, Punjab, Pakistan. Five rainwater and 24 groundwater samples from three different depths were analyzed. Shallow groundwater from 24 to 27 m depth contained high F - (2.47-21.1 mg/L), while the groundwater samples from the deeper depth were free from fluoride contamination. All groundwater samples contained high As (32-1900 μg/L), in excess of WHO drinking water standards. The SO 4 2- ranges from 110 to 1550 mg/L. δ 34 S data indicate three sources for SO 4 2- air pollutants (5.5-5.7 per mille ), fertilizers (4.8 per mille ), and household waste (7.0 per mille ). Our important finding is the presence of SO 4 2- , As and F - in rainwater, indicating the contribution of these elements from air pollution. We propose that pollutants originate, in part, from coal combusted at brick factories and were mobilized promotionally by the alkaline nature of the local groundwater. - Simultaneous As and F - contamination of groundwater and possible pollutant sources are discussed

  15. The Benefits and Risks of Consuming Brewed Tea: Beware of Toxic Element Contamination

    Directory of Open Access Journals (Sweden)

    Gerry Schwalfenberg

    2013-01-01

    Full Text Available Background. Increasing concern is evident about contamination of foodstuffs and natural health products. Methods. Common off-the-shelf varieties of black, green, white, and oolong teas sold in tea bags were used for analysis in this study. Toxic element testing was performed on 30 different teas by analyzing (i tea leaves, (ii tea steeped for 3-4 minutes, and (iii tea steeped for 15–17 minutes. Results were compared to existing preferred endpoints. Results. All brewed teas contained lead with 73% of teas brewed for 3 minutes and 83% brewed for 15 minutes having lead levels considered unsafe for consumption during pregnancy and lactation. Aluminum levels were above recommended guidelines in 20% of brewed teas. No mercury was found at detectable levels in any brewed tea samples. Teas contained several beneficial elements such as magnesium, calcium, potassium, and phosphorus. Of trace minerals, only manganese levels were found to be excessive in some black teas. Conclusions. Toxic contamination by heavy metals was found in most of the teas sampled. Some tea samples are considered unsafe. There are no existing guidelines for routine testing or reporting of toxicant levels in “naturally” occurring products. Public health warnings or industry regulation might be indicated to protect consumer safety.

  16. Air-borne heavy metal contamination to dietary vegetables: a case study from India.

    Science.gov (United States)

    Pandey, J; Pandey, Richa; Shubhashish, K

    2009-12-01

    Contamination of edible parts of three dietary vegetables, Spinach (Spinacia oleracea L.), Radish (Raphanus sativus L.), and Tomato (Lycopersicon esculentum Mill.) by air-borne cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), and lead (Pb) was determined using pot culture experiments at three sites in the city of Varanasi, India. The data revealed that although Cr and Cu in vegetables remained below their safe limits, about 68% of the total samples contained Cd, Ni, and Pb above their respective safe limits of 1.5, 1.5, and 2.5 μg g(-1). Site wise synchrony and air accumulation factor (AAF) indicated that atmospheric deposition was the main contributor of metal contamination to vegetables. The study suggests that if the present trends of atmospheric deposition are continued, air-borne heavy metals will contaminate the agricultural produce with long-term health implications.

  17. Possible central nervous system oxygen toxicity seizures among US recreational air or enriched air nitrox open circuit diving fatalities 2004-2013.

    Science.gov (United States)

    Buzzacott, P; Denoble, P J

    2017-01-01

    The first diver certification programme for recreational 'enriched air nitrox' (EAN) diving was released in 1985. Concerns were expressed that many EAN divers might suffer central nervous system (CNS) oxygen toxicity seizures and drown. US fatalities on open-circuit scuba occurring between 2004-2013, where the breathing gas was either air or EAN, were identified. Causes of death and preceding circumstances were examined by a medical examiner experienced in diving autopsies. Case notes were searched for witnessed seizures at elevated partial pressures of oxygen. The dataset comprised 344 air divers (86%) and 55 divers breathing EAN (14%). EAN divers' fatal dives were deeper than air divers' (28 msw vs 18 msw, p < 0.0001). Despite this, of the 249 cases where a cause of death was established, only three EAN divers were considered to have possibly died following CNS oxygen toxicity seizures at depth (ppO2 132, 142 and 193 kPa). The analysis of recreational diving fatalities in the US over 10 years found just one death likely from CNS oxygen toxicity among EAN divers. A further two possible, although unlikely, cases were also found. Fears of commonplace CNS oxygen toxicity seizures while EAN diving have not apparently been realized.

  18. Quantitative assessment of bio-aerosols contamination in indoor air of University dormitory rooms.

    Science.gov (United States)

    Hayleeyesus, Samuel Fekadu; Ejeso, Amanuel; Derseh, Fikirte Aklilu

    2015-07-01

    The purpose of this study is to provide insight into how students are exposed to indoor bio-aerosols in the dormitory rooms and to figure out the major possible factors that govern the contamination levels. The Bio-aerosols concentration level of indoor air of thirty dormitory rooms of Jimma University was determined by taking 120 samples. Passive air sampling technique; the settle plate method using open Petri-dishes containing different culture media was employed to collect sample twice daily. The range of bio-aerosols contamination detected in the dormitory rooms was 511-9960 CFU/m(3) for bacterial and 531-6568 CFU/m(3) for fungi. Based on the criteria stated by WHO expert group, from the total 120 samples 95 of the samples were above the recommended level. The statistical analysis showed that, occupancy were significantly affected the concentrations of bacteria that were measured in all dormitory rooms at 6:00 am sampling time (p-value=0.000) and also the concentrations of bacteria that were measured in all dormitory rooms were significantly different to each other (p-value=0.013) as of their significance difference in occupancy (p-value=0.000). Moreover, there were a significant different on the contamination level of bacteria at 6:00 am and 7:00 pm sampling time (p=0.015), whereas there is no significant difference for fungi contamination level for two sampling times (p= 0.674). There is excessive bio-aerosols contaminant in indoor air of dormitory rooms of Jimma University and human occupancy produces a marked concentration increase of bacterial contamination levels and most fungi species present into the rooms air of Jimma University dormitory were not human-borne.

  19. An analysis of candidates for addition to the Clean Air Act list of hazardous air pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Sonya Lunder; Tracey J. Woodruff; Daniel A. Axelrad [University of California, Berkeley, CA (United States). School of Public Health

    2004-02-01

    There are 188 air toxics listed as hazardous air pollutants (HAPs) in the Clean Air Act (CAA), based on their potential to adversely impact public health. This paper presents several analyses performed to screen potential candidates for addition to the HAPs list. We analyzed 1086 HAPs and potential HAPs, including chemicals regulated by the state of California or with emissions reported to the Toxics Release Inventory (TRI). HAPs and potential HAPs were ranked by their emissions to air, and by toxicity-weighted (tox-wtd) emissions for cancer and noncancer, using emissions information from the TRI and toxicity information from state and federal agencies. Separate consideration was given for persistent, bioaccumulative toxins (PBTs), reproductive or developmental toxins, and chemicals under evaluation for regulation as toxic air contaminants in California. Forty-four pollutants were identified as candidate HAPs based on three ranking analyses and whether they were a PBT or a reproductive or developmental toxin. Of these, nine qualified in two or three different rankings (ammonia (NH{sub 3}), copper (Cu), Cu compounds, nitric acid (HNO{sub 3}), N-methyl-2-pyrrolidone, sulfuric acid (H{sub 2}SO{sub 4}), vanadium (V) compounds, zinc (Zn), and Zn compounds). This analysis suggests further evaluation of several pollutants for possible addition to the CAA list of HAPs. 28 refs., 2 figs., 11 tabs.

  20. Comparative study for toxic elements determination in air particulate reference material by INAA, CCT-ICP-MS, and ICP-MS

    International Nuclear Information System (INIS)

    Lim, J.M.; Lee, J.H.; Kim, K.H.; Moon, J.H.; Chung, Y.S.

    2005-01-01

    Although toxic elements are minor components in the atmospheric environment, they play a significant role as important marker for atmospheric science such as risk assessment, long-range transfer study, and source apportionment. Therefore, the techniques, which allow accurate and fast elemental analysis with a minimum pre-treatment, are very important. INAA has a main advantage of non-destruction of air particulate samples, while inductively Coupled plasma with mass spectrometry (ICP-MS) encounters the most significant difficulties in pre-treatment (digestion, fusion, and dilution) and polyatomic spectral interferences for interest toxic elements, Although INAA is still reference method, a number of factors (disadvantages of cost, complexity of the instruments, and scarcity of nuclear reactor) limit its applications. To date, the use of collision cell technology ICP-MS (CCT-ICP-MS) is recommended instead of typical ICP-MS for the analysis of the toxic elements; this is because CCT-ICP-MS technique prevents polyatomic spectral interferences despite of contamination and volatile effects. In this study, a number of toxic elements in reference material, NIST SRM 2783 (air particulate on filter media) were determined by INAA, CCT-ICP-MS, and ICP-MS. For both ICP methods, the filters were decomposed by microwave digestion with 5mL nitric acid. The analytical results by three methods were compared with certificated data; the INAA results showed the most accurate and precise data sets for all target elements among three methods. In detail, the deviation between analytical results and SRM's by INAA fell below 10% for all elements excluding As (14%), while those by CCT-ICP-MS were about 20%. For ICP-MS, the result does not agree with certificated data for several elements, because polyatomic spectral interference (due to 40 Ar 35 Cl, 40 Ar 23 Na, and 35 Cl 16 O) generate positive error of analytical result for As, Cu, and V. Based on our result, INAA is still one of the most

  1. Contaminants in stream sediments from seven United States metropolitan areas: part II—sediment toxicity to the amphipod Hyalella azteca and the midge Chironomus dilutus

    Science.gov (United States)

    Kemble, Nile E.; Hardesty, Douglas K.; Ingersoll, Christopher G.; Kunz, James L.; Sibley, Paul K.; Calhoun, Daniel L.; Gilliom, Robert J.; Kuivila, Kathryn; Nowell, Lisa H.; Moran, Patrick W.

    2013-01-01

    Relationships between sediment toxicity and sediment chemistry were evaluated for 98 samples collected from seven metropolitan study areas across the United States. Sediment-toxicity tests were conducted with the amphipod Hyalella azteca (28 day exposures) and with the midge Chironomus dilutus (10 day exposures). Overall, 33 % of the samples were toxic to amphipods and 12 % of the samples were toxic to midge based on comparisons with reference conditions within each study area. Significant correlations were observed between toxicity end points and sediment concentrations of trace elements, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), or organochlorine (OC) pesticides; however, these correlations were typically weak, and contaminant concentrations were usually below sediment-toxicity thresholds. Concentrations of the pyrethroid bifenthrin exceeded an estimated threshold of 0.49 ng/g (at 1 % total organic carbon) in 14 % of the samples. Of the samples that exceeded this bifenthrin toxicity threshold, 79 % were toxic to amphipods compared with 25 % toxicity for the samples below this threshold. Application of mean probable effect concentration quotients (PECQs) based on measures of groups of contaminants (trace elements, total PAHs, total PCBs,OCpesticides, and pyrethroid pesticides [bifenthrin in particular]) improved the correct classification of samples as toxic or not toxic to amphipods compared with measures of individual groups of contaminants. Sediments are a repository for many contaminants released into surface waters. Because of this, organisms inhabiting sediments may be exposed to a wide range of contaminants (United States Environmental Protection Agency (USEPA) United States Environmental Protection Agency 2000; American Society for Testing and Materials [ASTM] American Society for Testing and Materials International 2012). Contaminants of potential concern in sediments typically include trace elements (metals

  2. Microbiological contamination of compressed air used in dentistry: an investigation.

    Science.gov (United States)

    Conte, M; Lynch, R M; Robson, M G

    2001-11-01

    The purpose of this preliminary investigation was twofold: 1) to examine the possibility of cross-contamination between a dental-evacuation system and the compressed air used in dental operatories and 2) to capture and identify the most common microflora in the compressed-air supply. The investigation used swab, water, and air sampling that was designed to track microorganisms from the evacuation system, through the air of the mechanical room, into the compressed-air system, and back to the patient. Samples taken in the vacuum system, the air space in the mechanical room, and the compressed-air storage tank had significantly higher total concentrations of bacteria than the outside air sampled. Samples of the compressed air returning to the operatory were found to match the outside air sample in total bacteria. It was concluded that the air dryer may have played a significant role in the elimination of microorganisms from the dental compressed-air supply.

  3. Oral bioaccessibility of toxic metals in contaminated oysters and relationships with metal internal sequestration.

    Science.gov (United States)

    Gao, Shi; Wang, Wen-Xiong

    2014-12-01

    The Hong Kong oysters Crassostrea hongkongensis are widely farmed in the estuarine waters of Southern China, but they accumulate Cu and Zn to alarmingly high concentrations in the soft tissues. Health risks of seafood consumption are related to contaminants such as toxic metals which are bioaccessible to humans. In the present study, we investigated the oral bioaccessibility of five toxic metals (Ag, Pb, Cd, Cu and Zn) in contaminated oysters collected from different locations of a large estuary in southern China. In all oysters, total Zn concentration was the highest whereas total Pb concentration was the lowest. Among the five metals, Ag had the lowest oral bioaccessibility (38.9-60.8%), whereas Cu and Zn had the highest bioaccessibility (72.3-93.1%). Significant negative correlation was observed between metal bioaccessibility and metal concentration in the oysters for Ag, Cd, and Cu. We found that the oral bioaccessibility of the five metals was positively correlated with their trophically available metal fraction (TAM) in the oyster tissues, and negatively correlated with metal distribution in the cellular debris. Thus, metal partitioning in the TAM and cellular debris controlled the oral bioaccessibility to humans. Given the dependence of oral bioaccessibility on tissue metal contamination, bioaccessibility needs to be incorporated in the risk assessments of contaminated shellfish. Copyright © 2014 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    Joe, Yun Haeng; Yoon, Ki Young; Hwang, Jungho

    2014-01-01

    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.

  5. 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.

  6. Micro GC's for Contaminant Monitoring in Spacecraft Air, Phase I

    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...

  7. Process for contamination containment of a workplace by means of an air jet

    International Nuclear Information System (INIS)

    Meline, F.

    1984-01-01

    Containment of pollution in an area, for example the room where nuclear fuel elements are cut, is obtained by an air curtain directed by a second air jet to improve the containment of pollutants. Contamined air is extracted by a cyclone and filtered [fr

  8. Assessment of correlation between leucocytes migration reaction and level of inhalation exposure to priority air contaminants

    Directory of Open Access Journals (Sweden)

    L.B. Masnavieva

    2017-09-01

    Full Text Available Nowadays each forth person suffers from allergic diseases and allergic pathology prevalence is constantly growing. There are compounds in air which are generally toxic, or have sensitizing or allergenic effects on a body. For example, we can name formaldehyde and nitrogen dioxide. Our research goal was to reveal a correlation between reaction of leucocytes migration inhibition to formaldehyde and level of inhalation exposure to the examined chemicals. We examined 410 teenag-ers who permanently lived in industrial cities in Irkutsk region. We studied individual load as per formaldehyde and nitrogen dioxide. We estimated eosinophils content in nasal mucus and determined indexes of leucocytes migration inhibition to for-maldehyde. Index of formaldehyde effects danger was detected to exceed 1 in 54% teenagers. The greatest value of danger coefficient in terms of exposure to this substance was equal to 1.76. anger index in terms of exposure to nitrogen dioxide didn't exceed 0.7 in the examined teenagers. The obtained results prove that inhalation formaldehyde load influences teenag-ers from industrial centers as sensitization to this substance evolves in them. We found out that true inhibition reaction of leucocytes migration in a reaction with formaldehyde more frequently occurred in people with danger index in terms of ex-posure to this substance being lower than 1. We obtained models which described correlation between level of sensitization to formaldehyde and a number of eosinophils in nasal mucus and it allowed us to detect that sensitization depended on the examined contaminants content in the air. The sensitization to chemical air contaminants which we revealed in teenagers calls for necessary activities aimed at reducing risks of allergenic pathology evolvement in them.

  9. EMISSIONS OF ORGANIC AIR TOXICS FROM OPEN ...

    Science.gov (United States)

    A detailed literature search was performed to collect and collate available data reporting emissions of toxic organic substances into the air from open burning sources. Availability of data varied according to the source and the class of air toxics of interest. Volatile organic compound (VOC) and polycyclic aromatic hydrocarbon (PAH) data were available for many of the sources. Data on semivolatile organic compounds (SVOCs) that are not PAHs were available for several sources. Carbonyl and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofuran (PCDD/F) data were available for only a few sources. There were several sources for which no emissions data were available at all. Several observations were made including: 1) Biomass open burning sources typically emitted less VOCs than open burning sources with anthropogenic fuels on a mass emitted per mass burned basis, particularly those where polymers were concerned; 2) Biomass open burning sources typically emitted less SVOCs and PAHs than anthropogenic sources on a mass emitted per mass burned basis. Burning pools of crude oil and diesel fuel produced significant amounts of PAHs relative to other types of open burning. PAH emissions were highest when combustion of polymers was taking place; and 3) Based on very limited data, biomass open burning sources typically produced higher levels of carbonyls than anthropogenic sources on a mass emitted per mass burned basis, probably due to oxygenated structures r

  10. Aerospace toxicology overview: aerial application and cabin air quality.

    Science.gov (United States)

    Chaturvedi, Arvind K

    2011-01-01

    Aerospace toxicology is a rather recent development and is closely related to aerospace medicine. Aerospace toxicology can be defined as a field of study designed to address the adverse effects of medications, chemicals, and contaminants on humans who fly within or outside the atmosphere in aviation or on space flights. The environment extending above and beyond the surface of the Earth is referred to as aerospace. The term aviation is frequently used interchangeably with aerospace. The focus of the literature review performed to prepare this paper was on aerospace toxicology-related subject matters, aerial application and aircraft cabin air quality. Among the important topics addressed are the following: · Aerial applications of agricultural chemicals, pesticidal toxicity, and exposures to aerially applied mixtures of chemicals and their associated formulating solvents/surfactants The safety of aerially encountered chemicals and the bioanalytical methods used to monitor exposures to some of them · The presence of fumes and smoke, as well as other contaminants that may generally be present in aircraft/space vehicle cabin air · And importantly, the toxic effects of aerially encountered contaminants, with emphasis on the degradation products of oils, fluids, and lubricants used in aircraft, and finally · Analytical methods used for monitoring human exposure to CO and HCN are addressed in the review, as are the signs and symptoms associated with exposures to these combustion gases. Although many agricultural chemical monitoring studies have been published, few have dealt with the occurrence of such chemicals in aircraft cabin air. However, agricultural chemicals do appear in cabin air; indeed, attempts have been made to establish maximum allowable concentrations for several of the more potentially toxic ones that are found in aircraft cabin air. In this article, I emphasize the need for precautionary measures to be taken to minimize exposures to aerially

  11. The major regularities of the air radioactive contamination of Belarus territory after the Chernobyl accident

    International Nuclear Information System (INIS)

    Konoplya, E. F.; Mironov, V. P.; Drugachenok, M. A.; Kudryashov, V.P; Grushevich, L.E; Adamovich, A.A.

    2001-01-01

    In the first days after the Chernobyl accident the radioactivity of surface air in different regions of Belarus has increased in tens and hundred thousand time. The regular control of air radioactive contamination in the zone of alienation and nearest to it is carried out from the end 1989. The radioactive air monitoring carried out in territories with various contamination density (from 0,2 up to 9,6 MBq/m 2 on Cs-137). The measurements of the Cs-137 contents in ashes of air sampler filters were carried out by gamma - spectrometer ADCAM-300 MCA. The measurement of the Pu-240,239 and Sr-90 contents was carried out by usual radiochemical techniques. The used techniques and equipment allow to define in a sample of the minimal activity: Pu-239,240 - 0,001 Bq, Cs-137 - 0,5 Bq, Sr-90 - 0,1 Bq. The initial contamination of ground happened a near zone within approximately first 2 weeks after accident. Since the end of May, 1986 till present time the air radioactive contamination is formed under action of processes of secondary wind rise and carry of radioactive particles with contaminated territories, which depends from a number factors of both natural and anthropogenous origin. The relations of Pu-238/Pu-239 and Sr-90/Pu-239 in aerosol particles practically coincide with the same relations in fuel blown up reactor. The ratio of Cs-137/Pu-239 activities in aerosols considerably exceeds the resettlement ratio for fuel. Strontium and plutonium are in structure of fuel particles, and cesium aerosol have other origin. The analysis of changes annual radioisotopes concentration in air of towns of Belarus specifies existence of the tendency to slow decrease of contamination of atmosphere by radioisotopes of industrial origins. The basic tendency of formation of air radioactive contamination is determined by the contents of a dust at surface layer of an atmosphere and its specific activity. Annual average dust content of air in a zone resettlement was least and made about 10 mk g

  12. Aerobic Bioremediation of PAH Contaminated Soil Results in Increased Genotoxicity and Developmental Toxicity

    Science.gov (United States)

    Chibwe, Leah; Geier, Mitra C.; Nakamura, Jun; Tanguay, Robert L.; Aitken, Michael D.; Simonich, Staci L. Massey

    2015-01-01

    The formation of more polar and toxic polycyclic aromatic hydrocarbon (PAH) transformation products is one of the concerns associated with the bioremediation of PAH-contaminated soils. Soil contaminated with coal tar (pre-bioremediation) from a former manufactured gas plant (MGP) site was treated in a laboratory scale bioreactor (post-bioremediation) and extracted using pressurized liquid extraction. The soil extracts were fractionated, based on polarity, and analyzed for 88 PAHs (unsubstituted, oxygenated, nitrated, and heterocyclic PAHs). The PAH concentrations in the soil tested, post-bioremediation, were lower than their regulatory maximum allowable concentrations (MACs), with the exception of the higher molecular weight PAHs (BaA, BkF, BbF, BaP, and IcdP), most of which did not undergo significant biodegradation. The soil extract fractions were tested for genotoxicity using the DT40 chicken lymphocyte bioassay and developmental to xicity using the embryonic zebrafish (Danio rerio) bioassay. A statistically significant increase in genotoxicity was measured in the unfractionated soil extract, as well as in four polar soil extract fractions, post-bioremediation (p bioremediation (p bioremediation. The increased toxicity measured post-bioremediation is not likely due to the 88 PAHs measured in this study (including quinones), because most were not present in the toxic polar fractions and/or because their concentrations did not increase post-bioremediation. However, the increased toxicity measured post-bioremediation is likely due to hydroxylated and carboxylated transformation products of the 3- and 4-ring PAHs (PHE, 1MPHE, 2MPHE, PRY, BaA, and FLA) that were most degraded. PMID:26200254

  13. Influence of a Brazilian sewage outfall on the toxicity and contamination of adjacent sediments

    Science.gov (United States)

    Abessa, D.M.S.; Carr, R.S.; Rachid, B.R.F.; Sousa, E.C.P.M.; Hortelani, M.A.; Sarkis, J.E.

    2005-01-01

    The submarine sewage outfall of Santos (SSOS) is situated in the Santos Bay (São Paulo, Brazil) and is potentially a significant source of contaminants to the adjacent marine ecosystem. The present study aimed to assess the influence of SSOS on the sediment toxicity and contamination at Santos Bay. At the disposal site, sediments tended to be finer, organically richer and exhibited higher levels of surfactants and metals, sometimes exceeding the “Threshold Effect Level” values. The SSOS influence was more evident toward the East, where the sediments exhibited higher levels of TOC, total S and metals during the summer 2000 sampling campaign. Sediment toxicity to amphipods was consistently detected in four of the five stations studied. Amphipod survival tended to correlate negatively to Hg, total N and % mud. This work provides evidence that the SSOS discharge affects the quality of sediments from Santos Bay, and that control procedures are warranted.

  14. Mitigation of trichloroethylene contaminated air streams through biofiltration: a pilot-scale study

    International Nuclear Information System (INIS)

    Lackey, L.W.; Gamble, J.R.; Boles, J.L.

    2002-01-01

    As a result of abundant usage and improper disposal practices, trichloroethylene (TCE) is one of the most prevalent groundwater contaminants. Traditional cleanup methods of aquifers contaminated with TCE include pumping the water to the surface and treating with stripper technology, soil vapor extraction, and air sparging. As a result of each of these mitigation schemes, TCE is transferred from the aqueous to the gas phase. As regulations associated with air emission tighten, development of technologies both technically feasible and cost effective for remediating TCE laden gas streams becomes imperative. This project demonstrated the use of biofiltration technology to mitigate TCE contaminated air streams. A pilot-scale biofilter system was designed, constructed, and subsequently installed at the Anniston Army Depot (ANAD), Anniston, AL. The system was inoculated with a propane-oxidizing microbial consortium that had previously been shown to degrade TCE as well as other short-chained chlorinated aliphatics and a variety of one-and two-ring aromatic compounds. Critical process variables were identified and their effects on system performance analyzed. Results indicated that the process scheme used to introduce propane into the biofiltration system had a significant impact on the observed TCE removal efficiency. The inlet contaminant concentration as well as the loading rate also had an impact on observed TCE degradation rates. Results suggest that biofilter performance and economics are generally improved by manipulating a specific waste stream so as to increase the TCE concentration and decrease the volumetric flow rate of the contaminated air fed to the biofilter. Through manipulation of process variables, including the empty bed contact time, TCE degradation efficiencies greater than 99.9 percent were sustained. No microbial inhibition was observed at inlet TCE concentrations as high as 87 parts per million on a volume basis (ppmv). (author)

  15. Spacecraft contamination programs within the Air Force Systems Command Laboratories

    Science.gov (United States)

    Murad, Edmond

    1990-01-01

    Spacecraft contamination programs exist in five independent AFSC organizations: Geophysics Laboratory (GL), Arnold Engineering and Development Center (AEDC), Rome Air Development Center (RADC/OSCE), Wright Research and Development Center (MLBT), Armament Laboratory (ATL/SAI), and Space Systems Division (SSD/OL-AW). In addition, a sizable program exists at Aerospace Corp. These programs are complementary, each effort addressing a specific area of expertise: GL's effort is aimed at addressing the effects of on-orbit contamination; AEDC's effort is aimed at ground simulation and measurement of optical contamination; RADC's effort addresses the accumulation, measurement, and removal of contamination on large optics; MLBT's effort is aimed at understanding the effect of contamination on materials; ATL's effort is aimed at understanding the effect of plume contamination on systems; SSD's effort is confined to the integration of some contamination experiments sponsored by SSD/CLT; and Aerospace Corp.'s effort is aimed at supporting the needs of the using System Program Offices (SPO) in specific areas, such as contamination during ground handling, ascent phase, laboratory measurements aimed at understanding on-orbit contamination, and mass loss and mass gain in on-orbit operations. These programs are described in some detail, with emphasis on GL's program.

  16. Concentrations, sources and human health risk of inhalation exposure to air toxics in Edmonton, Canada.

    Science.gov (United States)

    Bari, Md Aynul; Kindzierski, Warren B

    2017-04-01

    With concern about levels of air pollutants in recent years in the Capital Region of Alberta, an investigation of ambient concentrations, sources and potential human health risk of hazardous air pollutants (HAPs) or air toxics was undertaken in the City of Edmonton over a 5-year period (2009-2013). Mean concentrations of individual HAPs in ambient air including volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs) and trace metals ranged from 0.04 to 1.73 μg/m 3 , 0.01-0.54 ng/m 3 , and 0.05-3.58 ng/m 3 , respectively. Concentrations of benzene, naphthalene, benzo(a)pyrene (BaP), arsenic, manganese and nickel were far below respective annual Alberta Ambient Air Quality Objectives. Carcinogenic and non-carcinogenic risk of air toxics were also compared with risk levels recommended by regulatory agencies. Positive matrix factorization identified six air toxics sources with traffic as the dominant contributor to total HAPs (4.33 μg/m 3 , 42%), followed by background/secondary organic aerosol (SOA) (1.92 μg/m 3 , 25%), fossil fuel combustion (0.92 μg/m 3 , 11%). On high particulate air pollution event days, local traffic was identified as the major contributor to total HAPs compared to background/SOA and fossil fuel combustion. Carcinogenic risk values of traffic, background/SOA and metals industry emissions were above the USEPA acceptable level (1 × 10 -6 ), but below a tolerable risk (1 × 10 -4 ) and Alberta benchmark (1 × 10 -5 ). These findings offer useful preliminary information about current ambient air toxics levels, dominant sources and their potential risk to public health; and this information can support policy makers in the development of appropriate control strategies if required. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Toxicity and bioaccumulation of sediment-associated contaminants using freshwater invertebrates: A review of methods and applications

    Science.gov (United States)

    Ingersoll, C.G.; Ankley, G.T.; Benoit, D.A.; Brunson, E.L.; Burton, G.A.; Dwyer, F.J.; Hoke, R.A.; Landrum, P.F.; Norberg-King, T. J.; Winger, P.V.

    1995-01-01

    This paper reviews recent developments in methods for evaluating the toxicity and bioaccumulation of contaminants associated with freshwater sediments and summarizes example case studies demonstrating the application of these methods. Over the past decade, research has emphasized development of more specific testing procedures for conducting 10-d toxicity tests with the amphipod Hyalella azteca and the midge Chironomus tentans. Toxicity endpoints measured in these tests are survival for H. azteca and survival and growth for C. tentans. Guidance has also been developed for conducting 28-d bioaccumulation tests with the oligochaete Lumbriculus variegatus, including determination of bioaccumulation kinetics for different compound classes. These methods have been applied to a variety of sediments to address issues ranging from site assessments to bioavailability of organic and inorganic contaminants using field-collected and laboratory-spiked samples. Survival and growth of controls routinely meet or exceed test acceptability criteria. Results of laboratory bioaccumulation studies with L. variegatus have been confirmed with comparisons to residues (PCBs, PAHs, DDT) present from synoptically collected field populations of oligochaetes. Additional method development is currently underway to develop chronic toxicity tests and to provide additional data-confirming responses observed in laboratory sediment tests with natural benthic populations.

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

    International Nuclear Information System (INIS)

    Pekarek, 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

  19. Contaminant levels and toxicity of sediments and water of Baltimore Harbor and Back River, Maryland

    International Nuclear Information System (INIS)

    Logan, D.T.; Jacobs, F.; Mehrotra, N.

    1995-01-01

    The Patapsco and Back River Watershed drains the Baltimore metropolitan area, Maryland's most heavily industrialized and urbanized region. Due to the intensive development and industrialization of the Baltimore metropolitan area over the past 250 years, high levels of contaminants have been discharged into Baltimore Harbor on the Patapsco River and into the Back River. Pollutants historically discharged include heavy metals, petroleum hydrocarbons, pesticides, cyanide, sewage, other organic chemicals, and nutrients. Sources have included industrial and municipal discharges, sewerage overflows, urban runoff, and leaks and spills from vessels and on-land facilities. The Maryland Department of the Environment undertook this study of ambient conditions as part of a developing strategy to assess and improve conditions in the Chesapeake Bay and its tributaries. Past studies were compiled, evaluated, and synthesized to identify the areas of degraded conditions and contaminants of possible concern. Sediment contaminant levels were assessed using historical sediment chemistry data, Effects Range Low and Median concentrations (ER-L and ER-M) as toxicological benchmarks, and a sum of toxicity units approach for multiple contaminants. Data on toxicity testing and biological monitoring was compared to sediment and water quality data. Fish tissue data were used to examine bioaccumulated chemicals. A computerized Geographical Information System (GIS) was used to manipulate and display complex geographical data. The final identification of areas and chemicals of potential concern relied on a syntheses of these results as well as information on present and past contaminant loadings

  20. The water-soluble fraction of potentially toxic elements in contaminated soils: relationships between ecotoxicity, solubility and geochemical reactivity.

    Science.gov (United States)

    Rocha, L; Rodrigues, S M; Lopes, I; Soares, A M V M; Duarte, A C; Pereira, E

    2011-09-01

    To better understand the impacts posed by soil contamination to aquatic ecosystems it is crucial to characterise the links between ecotoxicity, chemical availability and geochemical reactivity of potentially toxic elements (PTE's) in soils. We evaluated the adverse effects of water extracts obtained from soils contaminated by chemical industry and mining, using a test battery including organisms from different trophic levels (bacteria, algae and daphnids). These tests provided a quick assessment of the ecotoxicity of soils with respect to possible adverse effects on aquatic organisms although the ecotoxicological responses could be related to the solubility of PTE's only to a limited extent. The analysis of results of bioassays together with the chemical characterisation of water extracts provided additional relevant insight into the role of conductivity, pH, Al, Fe, and Mn of soil extracts on toxicity to organisms. Furthermore, an important conclusion of this study was that the toxicity of extracts to the aquatic organisms could also be related to the soil properties (pH, Org C and Fe(ox)) and to the reactivity of PTE's in soils which in fact control the soluble fraction of the contaminants. The combined assessment of ecotoxicity in water fractions, solubility and geochemical reactivity of PTE's in soils provided a more comprehensive understanding of the bioavailability of inorganic contaminants than ecotoxicological or chemical studies alone and can therefore be most useful for environmental risks assessment of contaminated soils. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Environmental contaminants in food. Volume II-part a: working papers. I. Priority setting of toxic substances for guiding monitoring programs. II. Five case studies of environmental food contamination

    International Nuclear Information System (INIS)

    1980-01-01

    This volume contains working papers written for Office of Technology Assessment (OTA) to assist in preparation of the report Environmental Contaminants in Food. The contents include: (1) Priority setting of toxic substances for guiding monitoring programs; and (2) Five case studies of environmental food contamination

  2. Contamination of Ambient Air with Acinetobacter baumannii on Consecutive Inpatient Days.

    Science.gov (United States)

    Shimose, Luis A; Doi, Yohei; Bonomo, Robert A; De Pascale, Dennise; Viau, Roberto A; Cleary, Timothy; Namias, Nicholas; Kett, Daniel H; Munoz-Price, L Silvia

    2015-07-01

    Acinetobacter-positive patients had their ambient air tested for up to 10 consecutive days. The air was Acinetobacter positive for an average of 21% of the days; the rate of contamination was higher among patients colonized in the rectum than in the airways (relative risk [RR], 2.35; P = 0.006). Of the 6 air/clinical isolate pairs available, 4 pairs were closely related according to rep-PCR results. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Potentially toxic metal contamination of urban soils and roadside dust in Shanghai, China

    International Nuclear Information System (INIS)

    Shi Guitao; Chen Zhenlou; Xu Shiyuan; Zhang Ju; Wang Li; Bi Chunjuan; Teng Jiyan

    2008-01-01

    A detailed investigation was conducted to understand the contamination characteristics of a selected set of potentially toxic metals in Shanghai. The amount of Pb, Zn, Cu, Cr, Cd and Ni were determined from 273 soil/dust samples collected within urban area. The results indicated that concentration of all metals except Ni in soils was significant, and metal pollution was even severer in roadside dust. A series of metal spatial distribution maps were created through geostatistical analysis, and the pollution hotspots tended to associate with city core area, major road junctions, and the regions close to industrial zones. In attempt of identifying the source of metals through geostatistical and multivariate statistical analyses, it was concluded as follows: Pb, Zn and Cu mainly originated from traffic contaminants; soil Ni was associated with natural concentration; Cd largely came from point-sourced industrial pollution; and Cr, Ni in dust were mainly related to atmospheric deposition. - Human activities have led to high accumulation of potentially toxic metals in urban soils and roadside dust of Shanghai

  4. Potentially toxic metal contamination of urban soils and roadside dust in Shanghai, China

    Energy Technology Data Exchange (ETDEWEB)

    Shi Guitao [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China); Chen Zhenlou [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China)], E-mail: gt_shi@163.com; Xu Shiyuan [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China); Zhang Ju [School of Environment and Planning, Liaocheng University, Liaocheng 252059 (China); Wang Li; Bi Chunjuan [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China); Teng Jiyan [Shanghai Chongming Dongtan National Nature Reserve, Shanghai 202183 (China)

    2008-11-15

    A detailed investigation was conducted to understand the contamination characteristics of a selected set of potentially toxic metals in Shanghai. The amount of Pb, Zn, Cu, Cr, Cd and Ni were determined from 273 soil/dust samples collected within urban area. The results indicated that concentration of all metals except Ni in soils was significant, and metal pollution was even severer in roadside dust. A series of metal spatial distribution maps were created through geostatistical analysis, and the pollution hotspots tended to associate with city core area, major road junctions, and the regions close to industrial zones. In attempt of identifying the source of metals through geostatistical and multivariate statistical analyses, it was concluded as follows: Pb, Zn and Cu mainly originated from traffic contaminants; soil Ni was associated with natural concentration; Cd largely came from point-sourced industrial pollution; and Cr, Ni in dust were mainly related to atmospheric deposition. - Human activities have led to high accumulation of potentially toxic metals in urban soils and roadside dust of Shanghai.

  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. Distinct toxic interactions of TiO2 nanoparticles with four coexisting organochlorine contaminants on algae.

    Science.gov (United States)

    Zhang, Shuai; Deng, Rui; Lin, Daohui; Wu, Fengchang

    Engineered nanoparticles are increasingly discharged into the environment. After discharge, these nanoparticles can interact with co-existing organic contaminants, resulting in a phenomena referred to as 'joint toxicity'. This study evaluated joint toxicities of TiO 2 nanoparticles (TiO 2 NPs) with four different (atrazine, hexachlorobenzene, pentachlorobenzene, and 3,3',4,4'-tetrachlorobiphenyl) organochlorine contaminants (OCs) toward algae (Chlorella pyrenoidosa). The potential mechanisms underlying the joint toxicity were discussed, including TiO 2 NPs-OC interactions, effects of TiO 2 NPs and OCs on biophysicochemical properties of algae and effects of TiO 2 NPs and OCs on each other's bioaccumulation in algae. The results indicate that coexposure led to a synergistic effect on the joint toxicity for TiO 2 NPs-atrazine, antagonistic effect for TiO 2 NPs-hexachlorobenzene and TiO 2 NPs-3,3',4,4'-tetrachlorobiphenyl, and an additive effect for TiO 2 NPs-pentachlorobenzene. There was nearly no adsorption of OCs by TiO 2 NPs, and the physicochemical properties of TiO 2 NPs were largely unaltered by the presence of OCs. However, both OCs and NPs affected the biophysicochemical properties of algal cells and thereby influenced the cell surface binding and/or internalization. TiO 2 NPs significantly increased the bioaccumulation of each OC. However, with the exception of atrazine, the bioaccumulation of TiO 2 NPs decreased when used with each OC. The distinct joint toxicity outcomes were a result of the balance between the increased toxicities of OCs (increased bioaccumulations) and the altered toxicity of TiO 2 NPs (bioaccumulation can either increase or decrease). These results can significantly improve our understanding of the potential environmental risks associated with NPs.

  7. Bioluminescent Vibrio fischeri assays in the assessment of seasonal and spatial patterns in toxicity of contaminated river sediments

    Directory of Open Access Journals (Sweden)

    Sergio Jarque

    2016-11-01

    Full Text Available Several bacteria-based assays, notably Vibrio fischeri luminescence assays, are often used as environmental monitoring tool for toxicity in sediments that may serve as both sinks and secondary source of contamination in aquatic ecosystems. In this study, we used 30-s kinetic bioassays based on V. fischeri to evaluate the toxicity associated to sediments from five localities with different contamination inputs (Morava River and its tributary Drevnice River in the south-eastern part of the Czech Republic. Toxicity assessed as half maximal inhibitory concentration (IC50 over the course of a year-long sampling was compared in bottom sediments and freshly trapped particulate material. Standard approach based on testing of aqueous elutriates was compared with toxicity of whole sediments (contact suspension toxicity. Bottom sediments showed lower toxicity compared to freshly trapped suspended materials in all cases. On the other hand, standardized elutriates induced generally weaker effects than suspended sediments likely due to losses during the extraction process. Toxicity generally increased during winter reaching maximum peaks in early spring months in all five sites. Total organic carbon (TOC was found to be highly correlated with toxic effects. Toxicity from sites with direct industrial and agricultural water inputs also correlated with concentrations of metals, polycyclic aromatic hydrocarbons (PAHs and polychlorinated biphenyls (PCBs. Single time point sampling followed by the extraction and testing of elutriates, do not truly reflect the spatial and temporal variability in natural sediments and may lead to underestimation of ecotoxic risks.

  8. An assessment of the long-term impact of chemically toxic contaminants from the disposal of nuclear fuel waste

    International Nuclear Information System (INIS)

    Goodwin, B.W.; Garisto, N.C.; Barnard, J.W.

    1987-01-01

    This paper presents a study on the potential for impact on man of chemically toxic contaminants associated with the Canadian concept for the disposal of nuclear fuel waste. The elements of concern are determined through a series of screening criteria such as elemental abundances and solubilities. A systems variability analysis approach is then used to predict the possible concentrations of these elements that may arise in the biosphere. These concentrations are compared with environmental guidelines such as permissible levels in drinking water. Conclusions are made regarding the potential for the chemically toxic contaminants to have an impact on man. 54 refs

  9. Hazard identification of contaminated sites. Ranking potential toxicity of organic sediment extracts in crustacean and fish

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, J.; Sundberg, H.; Aakerman, G.; Grunder, K.; Eklund, B.; Breitholtz, M. [Dept. of Applied Environmental Science (ITM), Stockholm Univ. (Sweden)

    2008-09-15

    Background, aim, and scope: It is well known that contaminated sediments represent a potential long-term source of pollutants to the aquatic environment. To protect human and ecosystem health, it is becoming common to remediate contaminated sites. However, the great cost associated with, e.g., dredging in combination with the large numbers of contaminated sites makes it crucial to pinpoint those sites that are in greatest need of remediation. In most European countries, this prioritization process has almost exclusively been based on chemical analyses of known substances; only seldom toxicity data has been considered. The main objective of the current study was therefore to develop a tool for hazard identification of sediment by ranking potential toxicity of organic sediment extracts in a crustacean and a fish. A secondary objective was to investigate the difference in potential toxicity between compounds with different polarities. Materials and methods Early life stages of the crustacean Nitocra spinipes and the fish Oncorhynchus mykiss, which represent organisms from different trophic levels (primary and secondary consumer) and with different routes of exposure (i.e. ingestion through food, diffusive uptake, and maternal transfer), were exposed to hexane and acetone fractions (semi-polar compounds) of sediment from five locations, ranging from heavily to low contaminated. Preliminary tests showed that the extracts were non-bioavailable to the crustacean when exposed via water, and the extracts were therefore loaded on silica gel. Rainbow trout embryos were exposed using nano-injection technique. Results and discussion Clear concentration-response relationships of both mortality and larval development were observed in all tests with N. spinipes. Also for rainbow trout, the observed effects (e.g., abnormality, hemorrhage, asymmetric yolk sac) followed a dose-related pattern. Interestingly, our results indicate that some of the locations contained toxic semi

  10. Molecular-level removal of proteinaceous contamination from model surfaces and biomedical device materials by air plasma treatment.

    Science.gov (United States)

    Banerjee, K K; Kumar, S; Bremmell, K E; Griesser, H J

    2010-11-01

    Established methods for cleaning and sterilising biomedical devices may achieve removal of bioburden only at the macroscopic level while leaving behind molecular levels of contamination (mainly proteinaceous). This is of particular concern if the residue might contain prions. We investigated at the molecular level the removal of model and real-life proteinaceous contamination from model and practical surfaces by air plasma (ionised air) treatment. The surface-sensitive technique of X-ray photoelectron spectroscopy (XPS) was used to assess the removal of proteinaceous contamination, with the nitrogen (N1s) photoelectron signal as its marker. Model proteinaceous contamination (bovine serum albumin) adsorbed on to a model surface (silicon wafer) and the residual proteinaceous contamination resulting from incubating surgical stainless steel (a practical biomaterial) in whole human blood exhibited strong N1s signals [16.8 and 18.5 atomic percent (at.%), respectively] after thorough washing. After 5min air plasma treatment, XPS detected no nitrogen on the sample surfaces, indicating complete removal of proteinaceous contamination, down to the estimated XPS detection limit 10ng/cm(2). Applying the same plasma treatment, the 7.7at.% nitrogen observed on a clinically cleaned dental bur was reduced to a level reflective of new, as-received burs. Contact angle measurements and atomic force microscopy also indicated complete molecular-level removal of the proteinaceous contamination upon air plasma treatment. This study demonstrates the effectiveness of air plasma treatment for removing proteinaceous contamination from both model and practical surfaces and offers a method for ensuring that no molecular residual contamination such as prions is transferred upon re-use of surgical and dental instruments. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  11. Evaluation of Triple Containment Method for Air Transport of Contaminated Human

    National Research Council Canada - National Science Library

    Neville, J

    2003-01-01

    A triple containment system intended for transport of biologically contaminated human remains was tested for its ability to maintain integrity during exposure to altitude changes representative of air transport...

  12. Polychaete richness and abundance enhanced in anthropogenically modified estuaries despite high concentrations of toxic contaminants.

    Directory of Open Access Journals (Sweden)

    Katherine A Dafforn

    Full Text Available Ecological communities are increasingly exposed to multiple chemical and physical stressors, but distinguishing anthropogenic impacts from other environmental drivers remains challenging. Rarely are multiple stressors investigated in replicated studies over large spatial scales (>1000 kms or supported with manipulations that are necessary to interpret ecological patterns. We measured the composition of sediment infaunal communities in relation to anthropogenic and natural stressors at multiple sites within seven estuaries. We observed increases in the richness and abundance of polychaete worms in heavily modified estuaries with severe metal contamination, but no changes in the diversity or abundance of other taxa. Estuaries in which toxic contaminants were elevated also showed evidence of organic enrichment. We hypothesised that the observed response of polychaetes was not a 'positive' response to toxic contamination or a reduction in biotic competition, but due to high levels of nutrients in heavily modified estuaries driving productivity in the water column and enriching the sediment over large spatial scales. We deployed defaunated field-collected sediments from the surveyed estuaries in a small scale experiment, but observed no effects of sediment characteristics (toxic or enriching. Furthermore, invertebrate recruitment instead reflected the low diversity and abundance observed during field surveys of this relatively 'pristine' estuary. This suggests that differences observed in the survey are not a direct consequence of sediment characteristics (even severe metal contamination but are related to parameters that covary with estuary modification such as enhanced productivity from nutrient inputs and the diversity of the local species pool. This has implications for the interpretation of diversity measures in large-scale monitoring studies in which the observed patterns may be strongly influenced by many factors that covary with anthropogenic

  13. Microbial contamination level of air in animal waste utilization plants.

    Science.gov (United States)

    Chmielowiec-Korzeniowska, Anna; Tymczyna, Leszek; Drabik, Agata; Krzosek, Łukasz

    2016-01-01

    The aim of this research was evaluation of microbial contamination of air within and in the vicinity of animal waste disposal plants. Air samples were analyzed to determine total bacterial and fungal counts as well as microbial species composition. Measurements of climate conditions (temperature, humidity, air motion) and total dust concentration were also performed. Total numbers of bacteria and fungi surpassed the threshold limit values for production halls. The most abundant bacteria detected were those consisting of physiological microflora of animal dermis and mucosa. Fungal species composition proved to be most differentiated in the air beyond the plant area. Aspergillus versicolor, a pathogenic and allergenic filamentous fungus, was isolated only inside the rendering plant processing hall. The measurement results showed a low sanitary-hygienic state of air in the plant processing halls and substantial air pollution in its immediate vicinity.

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

    Science.gov (United States)

    Albrecht, Mark; Gauthier, Robert; Leaper, David

    2009-10-10

    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 µm size range, evidenced by a steep decrease in FAW blower filtration efficiency for particles 0.5 to 5.0 µm 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 µm) that could, conceivably, settle onto the surgical site.

  15. Evaluation of Legionella Air Contamination in Healthcare Facilities by Different Sampling Methods: An Italian Multicenter Study.

    Science.gov (United States)

    Montagna, Maria Teresa; De Giglio, Osvalda; Cristina, Maria Luisa; Napoli, Christian; Pacifico, Claudia; Agodi, Antonella; Baldovin, Tatjana; Casini, Beatrice; Coniglio, Maria Anna; D'Errico, Marcello Mario; Delia, Santi Antonino; Deriu, Maria Grazia; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Moro, Matteo; Mura, Ida; Pennino, Francesca; Privitera, Gaetano; Romano Spica, Vincenzo; Sembeni, Silvia; Spagnolo, Anna Maria; Tardivo, Stefano; Torre, Ida; Valeriani, Federica; Albertini, Roberto; Pasquarella, Cesira

    2017-06-22

    Healthcare facilities (HF) represent an at-risk environment for legionellosis transmission occurring after inhalation of contaminated aerosols. In general, the control of water is preferred to that of air because, to date, there are no standardized sampling protocols. Legionella air contamination was investigated in the bathrooms of 11 HF by active sampling (Surface Air System and Coriolis ® μ) and passive sampling using settling plates. During the 8-hour sampling, hot tap water was sampled three times. All air samples were evaluated using culture-based methods, whereas liquid samples collected using the Coriolis ® μ were also analyzed by real-time PCR. Legionella presence in the air and water was then compared by sequence-based typing (SBT) methods. Air contamination was found in four HF (36.4%) by at least one of the culturable methods. The culturable investigation by Coriolis ® μ did not yield Legionella in any enrolled HF. However, molecular investigation using Coriolis ® μ resulted in eight HF testing positive for Legionella in the air. Comparison of Legionella air and water contamination indicated that Legionella water concentration could be predictive of its presence in the air. Furthermore, a molecular study of 12 L. pneumophila strains confirmed a match between the Legionella strains from air and water samples by SBT for three out of four HF that tested positive for Legionella by at least one of the culturable methods. Overall, our study shows that Legionella air detection cannot replace water sampling because the absence of microorganisms from the air does not necessarily represent their absence from water; nevertheless, air sampling may provide useful information for risk assessment. The liquid impingement technique appears to have the greatest capacity for collecting airborne Legionella if combined with molecular investigations.

  16. Evaluation of Legionella Air Contamination in Healthcare Facilities by Different Sampling Methods: An Italian Multicenter Study

    Science.gov (United States)

    Montagna, Maria Teresa; De Giglio, Osvalda; Cristina, Maria Luisa; Napoli, Christian; Pacifico, Claudia; Agodi, Antonella; Baldovin, Tatjana; Casini, Beatrice; Coniglio, Maria Anna; D’Errico, Marcello Mario; Delia, Santi Antonino; Deriu, Maria Grazia; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Moro, Matteo; Mura, Ida; Pennino, Francesca; Privitera, Gaetano; Romano Spica, Vincenzo; Sembeni, Silvia; Spagnolo, Anna Maria; Tardivo, Stefano; Torre, Ida; Valeriani, Federica; Albertini, Roberto; Pasquarella, Cesira

    2017-01-01

    Healthcare facilities (HF) represent an at-risk environment for legionellosis transmission occurring after inhalation of contaminated aerosols. In general, the control of water is preferred to that of air because, to date, there are no standardized sampling protocols. Legionella air contamination was investigated in the bathrooms of 11 HF by active sampling (Surface Air System and Coriolis®μ) and passive sampling using settling plates. During the 8-hour sampling, hot tap water was sampled three times. All air samples were evaluated using culture-based methods, whereas liquid samples collected using the Coriolis®μ were also analyzed by real-time PCR. Legionella presence in the air and water was then compared by sequence-based typing (SBT) methods. Air contamination was found in four HF (36.4%) by at least one of the culturable methods. The culturable investigation by Coriolis®μ did not yield Legionella in any enrolled HF. However, molecular investigation using Coriolis®μ resulted in eight HF testing positive for Legionella in the air. Comparison of Legionella air and water contamination indicated that Legionella water concentration could be predictive of its presence in the air. Furthermore, a molecular study of 12 L. pneumophila strains confirmed a match between the Legionella strains from air and water samples by SBT for three out of four HF that tested positive for Legionella by at least one of the culturable methods. Overall, our study shows that Legionella air detection cannot replace water sampling because the absence of microorganisms from the air does not necessarily represent their absence from water; nevertheless, air sampling may provide useful information for risk assessment. The liquid impingement technique appears to have the greatest capacity for collecting airborne Legionella if combined with molecular investigations. PMID:28640202

  17. Benzimidazole for the prevention of toxic effects of air pollutants on plants

    Energy Technology Data Exchange (ETDEWEB)

    Takaoka, I; Fukuda, M; Kitano, H; Shinohara, T

    1974-02-02

    Tobacco plants were sprayed with benzimidazole before being exposed to 30 ppM of photochemical oxidants for a period of two hours. The plants were observed 48 hours after exposure and found to have suffered no toxic effects from the oxidants. It may be concluded that benzimidazole is an effective agent for preventing the toxic effects of air pollutants, such as photochemical oxidants on plants.

  18. INFLUENCE OF BACKGROUND AIR ON MICROBIAL-CONTAMINATION DURING SIMULATED IV-ADMIXTURE PREPARATION

    NARCIS (Netherlands)

    VANDOORNE, H; BAKKER, JH; MEEVIS, RF; MARSKAMP, A

    The effect of the cleanliness of environmental air on the microbial contamination of a simulated i.v.-admixture during its preparation by aseptic transfer was studied under three conditions: (i) in a laminar air flow (LAF) bench situated in a class 1000 clean room, (ii) in an LAF bench in a

  19. Toxic and hazardous air pollutants from co-firing biomass fuels, fossil fuels, MSW and RDF

    International Nuclear Information System (INIS)

    Junge, D.C.

    1991-01-01

    Toxic and hazardous pollutants are defined and then are considered from the perspective of pollutants which enter the combustion process with the fuel (principally the metals and metallic compounds) and pollutants which are formed as products of incomplete combustion. Control strategies are reviewed through the entire process including fuel preparation and storage, combustion control and the application of air pollution control devices. Measurement techniques for specific toxic and hazardous air pollutants are discussed

  20. Role of forestry in mitigating global soil pollution from toxic heavy ...

    African Journals Online (AJOL)

    One of the challenges confronting environmental management is the pollution of land, air and water resources by toxic heavy metals.This review seeks to identify the plant species and their potentials for remediation, less cost effective methods to remediate contaminated soils, and the remediation capability of woody plants.

  1. A longitudinal study of air contaminants in a newly built preschool. [Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Berglund, B. (Univ. of Stockholm, Sweden); Johansson, I.; Lindvall, T.

    1982-01-01

    The air quality in a newly built preschool was investigated in a longitudinal study. Typical air contaminants emanating from building materials were determined, their variation over time (0-18 months) was measured, and the influence of the ventilation system (81%-91% recirculation of return air) on contaminant concentrations was studied. Volatile organic compounds were sampled by adsorption on porous polymer, analysed by a GC/FID system, and identified by MS. A spatial build-up in concentration (ppb or ..mu..g/m/sup 3/ levels) is evident for all the organic compounds, as well as for CO/sub 2/, from the outdoor air, through the ventilation system, and through the rooms to the exhaust air. The longitudinal comparison over time shows that all the organic compounds decline in concentration mainly within the first 6 months of occupancy: 1-buttanol 4-14 times, toluene and pentanal + hexanal 2-4 times, while formaldehyde remained at a constant low level of 90 ppb (110 ..mu..g/m/sup 3/). It is difficult to believe that the problems of poor air quality in 100 preschools in Stockholm are caused by the organic compounds alone unless interactions occur. A preschool building needs to be gassed off during the first 6 months after its construction with no recirculation of return air allowed (outdoor air rate approx 4-5 ach). During at least 1-2 additional years, it is desired that the recirculation rate of return air is restricted, perhaps to 50%.

  2. The circulating air barrier: Effective prevention of liquid contaminant movement through soil

    International Nuclear Information System (INIS)

    Gill, R.; Towers, T.; Johnson, H.; Overbey, W.

    1995-01-01

    The environmental cleanup task facing the United States Department of Energy (DOE) presents enormous technical, planning and institutional challenges, including the need to develop new technologies that are faster, better, safer, and cheaper, in order to expedite site cleanup. Characterization of contaminated sediments resulting from past tank leaks, continued safe operations of the tanks, total confinement of leaking materials, secondary waste minimization, and final closure of the single shell tanks are five of the many facets of the storage tank issue at Hanford and elsewhere in the nation. Each of these issues are considered in the development of the Circulating Air Barrier (CAB). The Circulating Air Barrier system is a desiccant-type barrier designed to prevent the movement of liquid contaminants toward the groundwater by using an air circulation and processing system to lower the water saturation in a targeted subsurface zone below the saturation level required for liquid flow. Vertical or horizontal wells can be installed to create a matrix of air injection and production so that air flows across the target barrier zone to the production wells. In the event of a tank leak, the system serves as a tool for early detection and provides a means to withdraw volatile contaminants to the surface for treatment. Demonstration and full-scale CAB systems have been designed for the Hanford Site. This includes chemical and geological characterization; model development, sensitivity analysis and performance optimization; subsurface configuration and surface processing equipment design; and development of a test program with associated cost estimates

  3. Bioremediation of petroleum contaminated soil to combat toxicity on Withania somnifera through seed priming with biosurfactant producing plant growth promoting rhizobacteria.

    Science.gov (United States)

    Das, Amar Jyoti; Kumar, Rajesh

    2016-06-01

    Soil contaminated by Petroleum oil cannot be utilized for agricultural purposes due to hydrocarbon toxicity. Oil contaminated soil induces toxicity affecting germination, growth and productivity. Several technologies have been proposed for bioremediation of oil contaminated sites, but remediation through biosurfactant producing plant growth promontory rhizobacteria (PGPR) is considered to be most promising methods. In the present study the efficacy of seed priming on growth and pigment of Withania somnifera under petroleum toxicity is explored. Seeds of W. somnifera were primed with biosurfactant producing Pseudomonas sp. AJ15 with plant growth promoting traits having potentiality to utilized petroleum as carbon source. Results indicates that plant arose from priming seeds under various petroleum concentration expressed high values for all the parameters studied namely germination, shoot length, root length, fresh and dry weight and pigments (chlorophyll and carotenoid) as compared to non primed seed. Hence, the present study signifies that petroleum degrarding biosurfactant producing PGPR could be further used for management and detoxification of petroleum contaminated soils for growing economically important crops. Copyright © 2016. Published by Elsevier Ltd.

  4. Toxicity of vapor phase petroleum contaminants to microbial degrader communities

    International Nuclear Information System (INIS)

    Long, S.C.; Davey, C.A.

    1994-01-01

    Petroleum products constitute the largest quantity of synthetic organic chemical products produced in the US. They are comprised of mostly hydrocarbon constituents from many different chemical classes including alkenes, cycloalkanes, aromatic compounds, and polyaromatic hydrocarbons. Many petroleum constituents are classified as volatile organic compounds or VOCs. Petroleum products also constitute a major portion of environmental pollution. One emerging technology, with promise for applications to VOCs in subsurface soil environments, is bioventing coupled with soil vapor extraction. These technologies involve volatilization of contaminants into the soil gas phase by injection and withdrawal of air. This air movement causes enhancement of the aerobic microbial degradation of the mobilized vapors by the indigenous populations. This study investigated the effects of exposure of mixed, subsurface microbial communities to vapor phase petroleum constituents or vapors of petroleum mixtures. Soil slurries were prepared and plated onto mineral salts agar plates and exposed to vapor phase contaminants at equilibrium with pure product. Representative n-alkane, branched alkane, cycloalkane, and aromatic compounds were tested as well as petroleum product mixtures. Vapor exposure altered the numbers and morphologies of the colonies enumerated when compared to controls. However, even at high, equilibrium vapor concentrations, microbial degrader populations were not completely inhibited

  5. Radioactive air and surface contamination in Czechia and Slovakia

    International Nuclear Information System (INIS)

    Rumyantsev, V.V.

    1992-01-01

    Data are presented on the radioactive substance effluents into the environment in conditions of NPP normal operation and on the air contamination by 85 Kr due to operation of the European and Soviet plants for reprocessing spent nuclear fuel. Data are given on the dosage of the Czechoslovakia population due to the Chernobyl NPP accident

  6. Environmental survey to assess viral contamination of air and surfaces in hospital settings.

    Science.gov (United States)

    Carducci, A; Verani, M; Lombardi, R; Casini, B; Privitera, G

    2011-03-01

    The presence of pathogenic viruses in healthcare settings represents a serious risk for both staff and patients. Direct viral detection in the environment poses significant technical problems and the indirect indicators currently in use suffer from serious limitations. The aim of this study was to monitor surfaces and air in hospital settings to reveal the presence of hepatitis C virus, human adenovirus, norovirus, human rotavirus and torque teno virus by nucleic acid assays, in parallel with measurements of total bacterial count and haemoglobin presence. In total, 114 surface and 62 air samples were collected. Bacterial contamination was very low (air was 282 cfu/m(3). Overall, 19 (16.7%) surface samples tested positive for viral nucleic acids: one for norovirus, one for human adenovirus and 17 (14.9%) for torque teno virus (TTV). Only this latter virus was directly detected in 10 air samples (16.1%). Haemoglobin was found on two surfaces. No relationship was found between viral, biochemical or bacterial indicators. The data obtained confirm the difficulty of assessing viral contamination using bacterial indicators. The frequent detection of TTV suggests its possible use as an indicator for general viral contamination of the environment. Copyright © 2010 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.

  7. 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.

  8. Mitigating with macrophytes: submersed plants reduce the toxicity of pesticide-contaminated water to zooplankton.

    Science.gov (United States)

    Brogan, William R; Relyea, Rick A

    2013-03-01

    In ecotoxicology, appreciation is growing for the influence that ecological interactions have on the toxicity of contaminants, such as insecticides, to sensitive species. Most previous studies, however, have focused on factors that exacerbate insecticide effects on species, while factors that may mitigate these effects have been relatively ignored. In aquatic habitats, a small number of studies have shown that submersed macrophytes can remove some insecticides from the water column via sorption. Although examining sorption dynamics is important for understanding the environmental fate of insecticides, whether and to what extent macrophytes actually mitigate insecticide effects on aquatic species remains unknown. In the present study, the authors examined how much and how quickly several realistic densities of the macrophyte Elodea canadensis decreased the toxicity of the insecticide malathion to Daphnia magna, a keystone aquatic herbivore. To do this, the authors quantified Daphnia survival in outdoor test systems (0.95 L) exposed to a factorial combination of five Elodea densities crossed with five malathion concentrations. The authors discovered that malathion's lethality to Daphnia decreased with increasing Elodea density. Furthermore, the rate at which Elodea reduced malathion's toxicity in the water column increased with macrophyte density. These results provide strong evidence that submersed macrophytes can mitigate the ecological impacts of a popular insecticide and further support that ecological interactions can strongly influence contaminant environmental effects. Copyright © 2013 SETAC.

  9. Pilot study investigating ambient air toxics emissions near a Canadian kraft pulp and paper facility in Pictou County, Nova Scotia.

    Science.gov (United States)

    Hoffman, Emma; Guernsey, Judith R; Walker, Tony R; Kim, Jong Sung; Sherren, Kate; Andreou, Pantelis

    2017-09-01

    Air toxics are airborne pollutants known or suspected to cause cancer or other serious health effects, including certain volatile organic compounds (VOCs), prioritized by the US Environmental Protection Agency (EPA). While several EPA-designated air toxics are monitored at a subset of Canadian National Air Pollution Surveillance (NAPS) sites, Canada has no specific "air toxics" control priorities. Although pulp and paper (P&P) mills are major industrial emitters of air pollutants, few studies quantified the spectrum of air quality exposures. Moreover, most NAPS monitoring sites are in urban centers; in contrast, rural NAPS sites are sparse with few exposure risk records. The objective of this pilot study was to investigate prioritized air toxic ambient VOC concentrations using NAPS hourly emissions data from a rural Pictou, Nova Scotia Kraft P&P town to document concentration levels, and to determine whether these concentrations correlated with wind direction at the NAPS site (located southwest of the mill). Publicly accessible Environment and Climate Change Canada data (VOC concentrations [Granton NAPS ID: 31201] and local meteorological conditions [Caribou Point]) were examined using temporal (2006-2013) and spatial analytic methods. Results revealed several VOCs (1,3-butadiene, benzene, and carbon tetrachloride) routinely exceeded EPA air toxics-associated cancer risk thresholds. 1,3-Butadiene and tetrachloroethylene were significantly higher (p towns and contribute to poor health in nearby communities.

  10. Numerical Study of Contaminant Effects on Combustion of Hydrogen, Ethane, and Methane in Air

    Science.gov (United States)

    Lai, H. T.; Thomas, S. R.

    1995-01-01

    A numerical study was performed to assess the effects of vitiated air on the chemical kinetics of hydrogen, ethane, and methane combustion with air. A series of calculations in static reacting systems was performed, where the initial temperature was specified and reactions occurred at constant pressure. Three different types of test flow contaminants were considered: NP, H2O, and a combustion of H2O and CO2. These contaminants are present in the test flows of facilities used for hypersonic propulsion testing. The results were computed using a detailed reaction mechanism and are presented in terms of ignition and reaction times. Calculations were made for a wide range of contaminant concentrations, temperatures and pressures. The results indicate a pronounced kinetic effect over a range of temperatures, especially with NO contamination and, to a lesser degree, with H2O contamination. In all cases studied, CO2 remained kinetically inert, but had a thermodynamic effect on results by acting as a third body. The largest effect is observed with combustion using hydrogen fuel, less effect is seen with combustion of ethane, and little effect of contaminants is shown with methane combustion.

  11. Proceedings: Second international conference on managing hazardous air pollutants, 1993

    International Nuclear Information System (INIS)

    Chow, W.; Levin, L.

    1994-09-01

    This volume contains the Proceedings of the Second International Conference on Managing Hazardous Air Pollutants, held in Washington, DC on July 13--15, 1993. This conference provided an important forum for sharing information and strategies at a critical time for electric utilities in the US and elsewhere. As mandated by the Clean Air Act Amendments of 1990, the US EPA is currently conducting a risk analysis of air toxic emissions from power plants which is expected in November 1995. This conference presented the results of recent research conducted by the EPA and others that may eventually be reflected in an assessment of power plant risks. New research in a number of areas will provide important inputs to a comprehensive and credible risk assessment. These research areas include the concentrations of toxic contaminants in fossil fuels, the development and testing of improved methods for measuring toxics in power plant emissions, the effectiveness of control devices in removing specific air toxics, the transport and dispersion of toxics through the air and other media, and the potential responses of the human body and environment to exposure to these pollutants. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database

  12. Notification: Background Investigation Services New Assignment Notification: EPA’s Efforts to Incorporate Environmental Justice Into Clean Air Act Inspections for Air Toxics

    Science.gov (United States)

    The purpose of this memorandum is to notify you that the EPA OIG plans to begin the preliminary research phase of an evaluation of the U.S. EPA's efforts to incorporate environmental justice into Clean Air Act inspections for air toxics.

  13. Airborne persistent toxic substances (PTSs) in China: occurrence and its implication associated with air pollution.

    Science.gov (United States)

    Wang, Pu; Zhang, Qinghua; Li, Yingming; Matsiko, Julius; Zhang, Ya; Jiang, Guibin

    2017-08-16

    In recent years, China suffered from extensive air pollution due to the rapidly expanding economic and industrial developments. Its severe impact on human health has raised great concern currently. Persistent toxic substances (PTSs), a large group of environmental pollutants, have also received much attention due to their adverse effects on both the ecosystem and public health. However, limited studies have been conducted to reveal the airborne PTSs associated with air pollution at the national scale in China. In this review, we summarized the occurrence and variation of airborne PTSs in China, especially in megacities. These PTSs included polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), halogenated flame retardants (HFRs), perfluorinated compounds (PFCs), organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs) and heavy metals. The implication of their occurrence associated with air pollution was discussed, and the emission source of these chemicals was concluded. Most reviewed studies have been conducted in east and south China with more developed economy and industry. Severe contamination of airborne PTSs generally occurred in megacities with large populations, such as Guangzhou, Shanghai and Beijing. However, the summarized results suggested that industrial production and product consumption are the major sources of most PTSs in the urban environment, while unintentional emission during anthropogenic activities is an important contributor to airborne PTSs. It is important that fine particles serve as a major carrier of most airborne PTSs, which facilitates the long-range atmospheric transport (LRAT) of PTSs, and therefore, increases the exposure risk of the human body to these pollutants. This implied that not only the concentration and chemical composition of fine particles but also the absorbed PTSs are of particular concern when air pollution occurs.

  14. Air Monitoring Leads to Discovery of New Contamination at Radioactive Waste Disposal Site (Area G) at Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    Kraig, D.H.; Conrad, R.C.

    1999-01-01

    Air monitoring at Area G, the low-level radioactive waste disposal area at Los Alamos National Laboratory, revealed increased air concentrations of 239 Pu and 241 Am at one location along the north boundary. This air monitoring location is a couple of meters north of a dirt road used to access the easternmost part of Area G. Air concentrations of 238 Pu were essentially unaffected, which was puzzling because the 238 Pu and 239 Pu are present in the local, slightly contaminated soils. Air concentrations of these radionuclides increased about a factor of ten in early 1995 and remained at those levels until the first quarter of 1996. During the spring of 1996 air concentrations again increased by a factor of about ten. No other radionuclides were elevated and no other Area G stations showed elevations of these radionuclides. After several formal meetings didn't provide an adequate cause for the elevations, a gamma survey was performed and showed a small area of significant contamination just south of the monitor location. We found in February, 1995, a trench for a water line had been dug within a meter of so of the air stations. Then, during early 1996, the dirt road was rerouted such that its new path was directly over the unknown contamination. It appears that the trenching brought contaminated material to the surface and caused the first rise in air concentrations and then the rerouting of the road over the contamination caused the second rise, during 1996. We also found that during 1976 and 1977 contaminated soils from the clean-up of an old processing facility had been spread over the filled pits in the vicinity of the air monitors. These soils were very low in 238Pu which explains why we saw very little 238 Pu in the increased air concentrations. A layer of gravel and sand was spread over the contaminated area. Although air concentrations of 239 Pu and 241 Am dropped considerably, the y have not returned to pre-1995 levels

  15. Air toxic emissions from the combustion of coal: Identifying and quantifying hazardous air pollutants from US coals

    Energy Technology Data Exchange (ETDEWEB)

    Szpunar, C.B.

    1992-09-01

    This report addresses the key air toxic emissions likely to emanate from continued and expanded use of domestic coal. It identifies and quantifies those trace elements specified in the US 1990 Clean Air Act Amendments, by tabulating selected characterization data on various source coals by region, state, and rank. On the basis of measurements by various researchers, this report also identifies those organic compounds likely to be derived from the coal combustion process (although their formation is highly dependent on specific boiler configurations and operating conditions).

  16. Air toxic emissions from the combustion of coal: Identifying and quantifying hazardous air pollutants from US coals

    International Nuclear Information System (INIS)

    Szpunar, C.B.

    1992-09-01

    This report addresses the key air toxic emissions likely to emanate from continued and expanded use of domestic coal. It identifies and quantifies those trace elements specified in the US 1990 Clean Air Act Amendments, by tabulating selected characterization data on various source coals by region, state, and rank. On the basis of measurements by various researchers, this report also identifies those organic compounds likely to be derived from the coal combustion process (although their formation is highly dependent on specific boiler configurations and operating conditions)

  17. Air-Seawater Exchange of Organochlorine Pesticides along the Sediment Plume of a Large Contaminated River.

    Science.gov (United States)

    Lin, Tian; Guo, Zhigang; Li, Yuanyuan; Nizzetto, Luca; Ma, Chuanliang; Chen, Yingjun

    2015-05-05

    Gaseous exchange fluxes of organochlorine pesticides (OCPs) across the air-water interface of the coastal East China Sea were determined in order to assess whether the contaminated plume of the Yangtze River could be an important regional source of OCPs to the atmosphere. Hexachlorocyclohexanes (HCHs), chlordane compounds (CHLs), and dichlorodiphenyltrichloroethanes (DDTs) were the most frequently detected OCPs in air and water. Air-water exchange was mainly characterized by net volatilization for all measured OCPs. The net gaseous exchange flux ranged 10-240 ng/(m2·day) for γ-HCH, 60-370 ng/(m2·day) for trans-CHL, 97-410 ng/(m2·day) for cis-CHL, and ∼0 (e.g., equilibrium) to 490 ng/(m2·day) for p,p'-DDE. We found that the plume of the large contaminated river can serve as a significant regional secondary atmospheric source of legacy contaminants released in the catchment. In particular, the sediment plume represented the relevant source of DDT compounds (especially p,p'-DDE) sustaining net degassing when clean air masses from the open ocean reached the plume area. In contrast, a mass balance showed that, for HCHs, contaminated river discharge (water and sediment) plumes were capable of sustaining volatilization throughout the year. These results demonstrate the inconsistencies in the fate of HCHs and DDTs in this large estuarine system with declining primary sources.

  18. 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. Copyright © 2016 Elsevier GmbH. All rights reserved.

  19. The importance of determining the air exchange rate in flats and buildings for calculations of the averted indoor inhalation doses arising from contaminated outdoor air

    International Nuclear Information System (INIS)

    Jilek, Karel; Thomas, J.; Bulanek, B.; Lenk, J.; Marikova, S.

    2015-01-01

    The indoor-outdoor air exchange rate is an important parameter when refining estimates of the averted inhaled doses to population in houses and buildings after an emergency event resulting in contamination of outdoor air with a radioactive material. The air exchange rates measured in 70 occupied houses and in 20 unoccupied houses using N 2 O as the tracer gas are presented, and the results of modelling the averted doses in the residential buildings for both gaseous and aerosol outdoor contaminants are demonstrated. (orig.)

  20. 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. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. [Disinfectants and main sanitary and preventive measures for protection of ventilation and air-conditioning systems from Legionella contamination].

    Science.gov (United States)

    Gerasimov, V N; Golov, E A; Khramov, M V; Diatlov, I A

    2008-01-01

    The study was devoted to selection and assessment of disinfecting preparations for prevention of contamination by Legionella. Using system of criteria for quality assessment of disinfectants, seven newdomestic ones belonging to quaternary ammonium compounds class or to oxygen-containing preparations and designed for disinfecting of air-conditioning and ventilation systems were selected. Antibacterial and disinfecting activities of working solutions of disinfectants were tested in laboratory on the test-surfaces and test-objects of premises' air-conditioning and ventilation systems contaminated with Legionella. High antimicrobial and disinfecting activity of new preparations "Dezactiv-M", "ExtraDez", "Emital-Garant", "Aquasept Plus", "Samarovka", "Freesept", and "Ecobreeze Oxy" during their exposure on objects and materials contaminated with Legionella was shown. Main sanitary and preventive measures for defending of air-conditioning and ventilation systems from contamination by Legionella species were presented.

  2. Potential contamination of shipboard air samples by diffusive emissions of PCBs and other organic pollutants: implications and solutions.

    Science.gov (United States)

    Lohmann, Rainer; Jaward, Foday M; Durham, Louise; Barber, Jonathan L; Ockenden, Wendy; Jones, Kevin C; Bruhn, Regina; Lakaschus, Soenke; Dachs, Jordi; Booij, Kees

    2004-07-15

    Air samples were taken onboard the RRS Bransfield on an Atlantic cruise from the United Kingdom to Halley, Antarctica, from October to December 1998, with the aim of establishing PCB oceanic background air concentrations and assessing their latitudinal distribution. Great care was taken to minimize pre- and post-collection contamination of the samples, which was validated through stringent QA/QC procedures. However, there is evidence that onboard contamination of the air samples occurred,following insidious, diffusive emissions on the ship. Other data (for PCBs and other persistent organic pollutants (POPs)) and examples of shipboard contamination are presented. The implications of these findings for past and future studies of global POPs distribution are discussed. Recommendations are made to help critically appraise and minimize the problems of insidious/diffusive shipboard contamination.

  3. An Assessment of Air As a Source of DNA Contamination Encountered When Performing PCR

    OpenAIRE

    Witt, Nina; Rodger, Gillian; Vandesompele, Jo; Benes, Vladimir; Zumla, Alimuddin; Rook, Graham A.; Huggett, Jim F.

    2009-01-01

    Sensitive molecular methods, such as the PCR, can detect low-level contamination, and careful technique is required to reduce the impact of contaminants. Yet, some assays that are designed to detect high copy-number target sequences appear to be impossible to perform without contamination, and frequently, personnel or laboratory environment are held responsible as the source. This complicates diagnostic and research analysis when using molecular methods. To investigate the air specifically as...

  4. 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

    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......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...

  5. 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.

  6. Detoxification, endocrine, and immune responses of tree swallow nestlings naturally exposed to air contaminants from the Alberta oil sands.

    Science.gov (United States)

    Cruz-Martinez, Luis; Fernie, Kim J; Soos, Catherine; Harner, Tom; Getachew, Fitsum; Smits, Judit E G

    2015-01-01

    Changes in environmental and wildlife health from contaminants in tailings water on the Canadian oil sands have been well-studied; however, effects of air contaminants on wildlife health have not. A field study was conducted to assess biological costs of natural exposure to oil sands-related air emissions on birds. Nest boxes for tree swallows (Tachycineta bicolor) were erected at two sites; within 5 km of active oil sands mining and extraction, and ≥ 60 km south, at one reference site. Passive air monitors were deployed at the nest boxes to measure nitrogen dioxide, sulfur dioxide, ozone, volatile organic compounds, and polycyclic aromatic hydrocarbons (PAHs). Nestlings were examined at day 9 post hatching to assess T cell function and morphometry. At day 14 post hatching, a subset of nestlings was euthanized to measure detoxification enzymes, endocrine changes, and histological alterations of immune organs. Except for ozone, all air contaminants were higher at the two oil sands sites than the reference site (up to 5-fold). Adult birds had similar reproductive performance among sites (p>0.05). Nestlings from industrial sites showed higher hepatic ethoxyresorufin O-dealkylase (EROD) induction (pfeather corticosterone (p>0.6), and no histological alterations in the spleen or bursa of Fabricius (p>0.05). This is the first report examining toxicological responses in wild birds exposed to air contaminants from industrial activity in the oil sands. It is also the first time that small, individual air contaminant monitors have been used to determine local contaminant levels in ambient air around nest boxes of wild birds. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. The effect of stable bedding materials on dust levels, microbial air contamination and equine respiratory health.

    Science.gov (United States)

    Kwiatkowska-Stenzel, Agnieszka; Witkowska, Dorota; Sowińska, Janina; Stopyra, Artur

    2017-12-01

    The choice of bedding material affects the quality of air in a stable and, consequently, the respiratory health of horses and humans. The risk of respiratory problems can be mitigated by improving the quality of air in the stable. The choice of bedding material is particularly important in cold climate conditions where horses are kept indoors throughout the year. This study examined the impact of three bedding materials: straw (S), peat with shavings (PS), and crushed wood pellets (CWP). The investigated factors were air contamination, including dust contamination and microbial (bacterial and fungal) contamination, and the condition of the equine respiratory tract. The condition of the respiratory tract was evaluated based on the results of arterial blood biochemistry tests and endoscopic evaluations of the upper respiratory tract. Mechanical dust contamination was lowest for PS (1.09mg/m 3 ) and highest for CWP (4.07mg/m 3 ). Bacterial contamination (in CFU - colony forming units) was highest for PS (5.14log 10 CFU/m 3 ) and lowest for CWP (4.81log 10 CFU/m 3 ). Fungal air contamination was lowest for CWP (4.54log 10 CFU/m 3 ) and highest for S (4.82log 10 CFU/m 3 ) and PS (4.88log 10 CFU/m 3 ). An analysis of physiological indicators revealed that all horses were clinically healthy regardless of the type of applied bedding. The type of bedding material did not exert a clear influence on arterial blood biochemistry or the results of endoscopic evaluations of the respiratory tract; however, the use of alternative for straw bedding materials improved endoscopy results. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Toxicity and the fractional distribution of trace metals accumulated from contaminated sediments by the clam Scrobicularia plana exposed in the laboratory and the field

    Energy Technology Data Exchange (ETDEWEB)

    Kalman, J., E-mail: judit.kalman@uca.es [Department of Life Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom); Bonnail-Miguel, E. [Department of Physical-Chemistry, University of Cadiz, Poligono Industrial Rio San Pedro s/n, 11,510 Puerto Real, Cadiz (Spain); Smith, B.D. [Department of Life Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom); Bury, N.R. [Division of Diabetes and Nutritional Science, King' s College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH (United Kingdom); Rainbow, P.S. [Department of Life Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom)

    2015-02-15

    The relationship between the subcellular distribution of accumulated toxic metals into five operational fractions (subsequently combined into presumed detoxified and non-detoxified components) and toxicity in the clam Scrobicularia plana was investigated under different laboratory exposures. Clams were exposed to metal contaminated media (water and diet) and analysed for the partitioning of accumulated As, Cu and Zn into subcellular fractions. In general, metallothionein-like proteins, metal-rich granules and cellular debris in different proportions acted as main storage sites of accumulated metals in the clam soft tissues for these three metals. No significant differences were noted in the accumulation rates of As, Cu and Zn of groups of individuals with or without apparent signs of toxicity after up to 30 days of exposure to naturally contaminated sediment mixtures. There was, however, an increased proportional accumulation of Cu in the non-detoxified fraction with increased Cu accumulation rate in the clams, suggesting that the Cu uptake rate from contaminated sediments exceeded the combined rates of elimination and detoxification of Cu, with the subsequent likelihood for toxic effects in the clams. - Highlights: • Scrobicularia plana accumulated As, Cu and Zn from naturally toxic sediments. • Toxic metals were accumulated in detoxified and non-detoxified components. • Cu accumulation in the non-detoxified pool increased with increased Cu uptake rate. • Cu uptake rate exceeded combined loss and detoxification rates to cause toxicity.

  9. Toxicity and the fractional distribution of trace metals accumulated from contaminated sediments by the clam Scrobicularia plana exposed in the laboratory and the field

    International Nuclear Information System (INIS)

    Kalman, J.; Bonnail-Miguel, E.; Smith, B.D.; Bury, N.R.; Rainbow, P.S.

    2015-01-01

    The relationship between the subcellular distribution of accumulated toxic metals into five operational fractions (subsequently combined into presumed detoxified and non-detoxified components) and toxicity in the clam Scrobicularia plana was investigated under different laboratory exposures. Clams were exposed to metal contaminated media (water and diet) and analysed for the partitioning of accumulated As, Cu and Zn into subcellular fractions. In general, metallothionein-like proteins, metal-rich granules and cellular debris in different proportions acted as main storage sites of accumulated metals in the clam soft tissues for these three metals. No significant differences were noted in the accumulation rates of As, Cu and Zn of groups of individuals with or without apparent signs of toxicity after up to 30 days of exposure to naturally contaminated sediment mixtures. There was, however, an increased proportional accumulation of Cu in the non-detoxified fraction with increased Cu accumulation rate in the clams, suggesting that the Cu uptake rate from contaminated sediments exceeded the combined rates of elimination and detoxification of Cu, with the subsequent likelihood for toxic effects in the clams. - Highlights: • Scrobicularia plana accumulated As, Cu and Zn from naturally toxic sediments. • Toxic metals were accumulated in detoxified and non-detoxified components. • Cu accumulation in the non-detoxified pool increased with increased Cu uptake rate. • Cu uptake rate exceeded combined loss and detoxification rates to cause toxicity

  10. Air contamination control as an element of state environmental monitoring

    International Nuclear Information System (INIS)

    Grabowski, D.

    1993-01-01

    The results of air contamination control on the base of gamma and beta radioactivity of aerosols collected on filters and in precipitation samples have been shown. The data have been gathered from 12 monitoring stations in Poland during 1993. No significant differences between actual results and those obtained in previous years have been noticed. 4 figs, 1 tab

  11. Methodology for contaminated sites of military activity territories restoration

    International Nuclear Information System (INIS)

    Khrushchov, D. P.; Yushchenko, Yu. V.; Shekhunova, S. B.

    2002-01-01

    Major part of Eastern Europe countries meet environmental problems related to sites of military activity. Major part of these sites is characterised with degradation of natural landscapes and contamination of geological environment with toxic and hazardous waste representing actual and potential danger for population and environment. Actual danger is caused with localisation of toxic waste, hazardous materials and waste which are preventing normal land use. Potential danger is related to successive dispersion of contamination in biosphere as well as origin of new derivatives and products having toxic and hazardous properties. The list of such sites and objects comprises bases of land, air and naval forces. These objects include a network of infrastructures: storages of fuels and lubricants (surface, underground), filling stations, pipe lines, reparation stations, garages, decontamination stations, underground storages of different purposes, depots (for ammunition, chemical products), hospitals, constructions, firing grounds (tank, artillery, aircraft bombing etc.) and waste disposal sites. Special programs aimed at military industries and bases contaminated sites remediation have been carrying out in developed countries (USA, United Kingdom, Germany etc.). This experience was used in the frames of joint programs having been founded in several countries of Central and Eastern Europe (Chesh Republic, Slovakia, Lithuania etc.). (author)

  12. Avoiding toxicity from water-borne contaminants in hemodialysis: new challenges in an era of increased demand for water.

    Science.gov (United States)

    Ward, Richard A

    2011-05-01

    Water is necessary for all hemodialysis treatments. However, drinking water contains a range of substances that are toxic to patients on hemodialysis. Thus, all dialysis facilities are equipped with a water treatment system that removes those substances from the water before it is used to prepare dialysate. Increased demand for water and ever-evolving drinking water regulations are leading to changes in drinking water quality that may compromise the ability of typical dialysis water treatment systems to adequately remove substances that are known to be toxic or to deal with unexpected increases in other substances of unknown toxicity. In addition to these external challenges to dialysis water quality, the growing recognition that microbial contaminants in dialysate contribute to long-term morbidity has led to more stringent microbiological quality standards for dialysate and a consequent need to control biofilm formation in the fluid pathways involved in dialysate preparation. Avoiding toxicity from water contaminants in this dynamic environment requires a comprehensive approach to water treatment, including flexibility regarding the choice of water treatment processes, close communication with the suppliers of drinking water, and an emphasis on training technicians responsible for monitoring and maintaining all aspects of the fluid handling systems. Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  13. 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.

  14. Mercury Toxicity and Contamination of Households from the Use of Skin Creams Adulterated with Mercurous Chloride (Calomel

    Directory of Open Access Journals (Sweden)

    Lori Copan

    2015-09-01

    Full Text Available Inorganic mercury, in the form of mercurous chloride, or calomel, is intentionally added to some cosmetic products sold through informal channels in Mexico and the US for skin lightening and acne treatment. These products have led to multiple cases of mercury poisoning but few investigations have addressed the contamination of cream users’ homes. We report on several cases of mercury poisoning among three Mexican-American families in California from use of mercury-containing skin creams. Each case resulted in widespread household contamination and secondary contamination of family members. Urine mercury levels in cream users ranged from 37 to 482 µg/g creatinine and in non-users from non-detectable to 107 µg/g creatinine. Air concentrations of up to 8 µg/m3 of mercury within homes exceeded the USEPA/ATSDR health-based guidance and action level of <1.0 μg/m3. Mercury contamination of cream users’ homes presented a multi-pathway exposure environment to residents. Homes required extensive decontamination, including disposal of most household items, to achieve acceptable air levels. The acceptable air levels used were not designed to consider multi-pathway exposure scenarios. These findings support that the calomel is able to change valence form to elemental mercury and volatilize once exposed to the skin or surfaces in the indoor environment.

  15. Toxicity of smelter slag-contaminated sediments from Upper Lake Roosevelt and associated metals to early life stage White Sturgeon (Acipenser transmontanus Richardson, 1836)

    Science.gov (United States)

    Little, E.E.; Calfee, R.D.; Linder, G.

    2014-01-01

    The toxicity of five smelter slag-contaminated sediments from the upper Columbia River and metals associated with those slags (cadmium, copper, zinc) was evaluated in 96-h exposures of White Sturgeon (Acipenser transmontanus Richardson, 1836) at 8 and 30 days post-hatch. Leachates prepared from slag-contaminated sediments were evaluated for toxicity. Leachates yielded a maximum aqueous copper concentration of 11.8 μg L−1 observed in sediment collected at Dead Man's Eddy (DME), the sampling site nearest the smelter. All leachates were nonlethal to sturgeon that were 8 day post-hatch (dph), but leachates from three of the five sediments were toxic to fish that were 30 dph, suggesting that the latter life stage is highly vulnerable to metals exposure. Fish maintained consistent and prolonged contact with sediments and did not avoid contaminated sediments when provided a choice between contaminated and uncontaminated sediments. White Sturgeon also failed to avoid aqueous copper (1.5–20 μg L−1). In water-only 96-h exposures of 35 dph sturgeon with the three metals, similar toxicity was observed during exposure to water spiked with copper alone and in combination with cadmium and zinc. Cadmium ranging from 3.2 to 41 μg L−1 or zinc ranging from 21 to 275 μg L−1 was not lethal, but induced adverse behavioral changes including a loss of equilibrium. These results suggest that metals associated with smelter slags may pose an increased exposure risk to early life stage sturgeon if fish occupy areas contaminated by slags.

  16. Comparison of solid-phase bioassays and ecoscores to evaluate the toxicity of contaminated soils.

    Science.gov (United States)

    Lors, Christine; Ponge, Jean-François; Martínez Aldaya, Maite; Damidot, Denis

    2010-08-01

    Five bioassays (inhibition of lettuce germination and growth, earthworm mortality, inhibition of springtail population growth, avoidance by springtails) were compared, using four coke factory soils contaminated by PAHs and trace elements, before and after biotreatment. For each bioassay, several endpoints were combined in an 'ecoscore', a measure of test sensitivity. Ecoscores pooled over all tested bioassays revealed that most organisms were highly sensitive to the concentration of 3-ring PAHs. When four soils were combined, behavioural tests using the springtail Folsomia candida showed higher ecoscores, i.e. they were most sensitive to soil contamination. However, despite overall higher sensitivity of behavioural tests, which could be used for cheap and rapid assessment of soil toxicity, especially at low levels of contamination, some test endpoints were more sensitive than others, and this may differ from a soil to another, pointing to the need for a battery of bioassays when more itemized results are expected. Copyright 2010 Elsevier Ltd. All rights reserved.

  17. Assessing the influence of compost and biochar amendments on the mobility and toxicity of metals and arsenic in a naturally contaminated mine soil.

    Science.gov (United States)

    Beesley, Luke; Inneh, Onyeka S; Norton, Gareth J; Moreno-Jimenez, Eduardo; Pardo, Tania; Clemente, Rafael; Dawson, Julian J C

    2014-03-01

    Amending contaminated soils with organic wastes can influence trace element mobility and toxicity. Soluble concentrations of metals and arsenic were measured in pore water and aqueous soil extracts following the amendment of a heavily contaminated mine soil with compost and biochar (10% v:v) in a pot experiment. Speciation modelling and toxicity assays (Vibrio fischeri luminescence inhibition and Lolium perenne germination) were performed to discriminate mechanisms controlling metal mobility and assess toxicity risk thereafter. Biochar reduced free metal concentrations furthest but dissolved organic carbon primarily controlled metal mobility after compost amendment. Individually, both amendments induced considerable solubilisation of arsenic to pore water (>2500 μg l(-1)) related to pH and soluble phosphate but combining amendments most effectively reduced toxicity due to simultaneous reductions in extractable metals and increases in soluble nutrients (P). Thus the measure-monitor-model approach taken determined that combining the amendments was most effective at mitigating attendant toxicity risk. Copyright © 2013 Elsevier Ltd. All rights reserved.

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

    International Nuclear Information System (INIS)

    Kim, Yang Seon; Yoon, Ki Young; Park, Jae Hong; Hwang, Jungho

    2011-01-01

    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: →This study examined the effects of air ions generated by a carbon fiber ionizer on the inactivation of bioaerosols. →When the ion exposure time and the ion generation concentration were increased, the antibacterial efficiency increased. →The bioaerosols carried a significant number of negative electrical charges. →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. Integration of processes induced air flotation and photo-Fenton for treatment of residual waters contaminated with xylene

    International Nuclear Information System (INIS)

    Silva, Syllos S. da; Chiavone-Filho, Osvaldo; Barros Neto, Eduardo L. de; Nascimento, Claudio A.O.

    2012-01-01

    Highlights: ► 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. ► We have selected xylene as representative contaminant due to properties of toxicity, solubility in water and vapor pressure. ► 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 −1 for the surfactant EO 7. Degradation efficiencies of organic loading were assessed using factorial planning. Statistical data analysis shows that H 2 O 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.

  20. Colombian legislation for air contamination control; Legislacion colombiana para el control de la contaminacion del aire

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez S, Gildardo; Montes de Correa, Consuelo

    1999-12-01

    The most relevant legislative acts promulgated by the Colombian government for controlling atmospheric pollution are reviewed in chronological order. Special emphasis is paid to decree 948 of 1995 modified according to decree 2107 of 1995, e. The general dispositions about norms of air quality, emission levels, contaminant emissions, noise and offensive odors (chapter II), as well as, prohibitions and restrictions to emissions and noise from stationary and mobile sources (chapters III-V) furthermore, the resolutions issued so far by the ministry of the environment for regulating decree 948/95 in those aspects related to the prevention and control of atmospheric pollution are describes. Finally, the main philosophies for regulating air pollutants around the world are explained: the emissions norms, air quality norms, the emission taxes philosophy and the cost-benefit norms.

  1. Migratory birds are the source of highly toxic organic pollutants for indigenous people in the Russian Arctic

    Science.gov (United States)

    Pesiakova, A. A.; Gusakova, E. V.; Trofimova, A. N.; Sorokina, T. Yu

    2018-01-01

    Polychlorinated biphenyls are highly toxic organic contaminants. Due to their chemical properties they had wide application in industry and agriculture in the 20th century. In 2001 the production of PCBs has been prohibited almost worldwide. Environmental contamination has been found in soils, water, and air where there were PCB production sites. They have been detected in fish, birds and animals of migratory species, retaining transboarding transfer. Several migratory species of birds (Taiga bean goose, greater white-fronted goose, lesser white fronted goose and barnacle goose) are a diet for indigenous people. PCBs accumulating in the human body affect all systems and organs. This article reviews the contribution of migratory bird species in transboarding transfer of highly toxic contaminants in the Nenets Autonomous Area, Kolguev island (Russian Arctic).

  2. Controlling air toxics through advanced coal preparation

    Energy Technology Data Exchange (ETDEWEB)

    Straszheim, W.E.; Buttermore, W.H.; Pollard, J.L. [Iowa State Univ., Ames, IA (United States)

    1995-11-01

    This project involves the assessment of advanced coal preparation methods for removing trace elements from coal to reduce the potential for air toxic emissions upon combustion. Scanning electron microscopy-based automated image analysis (SEM-AIA) and advanced washability analyses are being applied with state-of-the-art analytical procedures to predict the removal of elements of concern by advanced column flotation and to confirm the effectiveness of preparation on the quality of quantity of clean coal produced. Specific objectives are to maintain an acceptable recovery of combustible product, while improving the rejection of mineral-associated trace elements. Current work has focused on determining conditions for controlling column flotation system across its operating range and on selection and analysis of samples for determining trace element cleanability.

  3. 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.

  4. Environmental contaminants and microRNA regulation: Transcription factors as regulators of toxicant-altered microRNA expression

    Energy Technology Data Exchange (ETDEWEB)

    Sollome, James; Martin, Elizabeth [Department of Environmental Science & Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill (United States); Sethupathy, Praveen [Department of Genetics, School of Medicine, University of North Carolina, Chapel Hill, NC (United States); Fry, Rebecca C., E-mail: rfry@unc.edu [Department of Environmental Science & Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill (United States); Curriculum in Toxicology, School of Medicine, University of North Carolina, Chapel Hill, NC (United States)

    2016-12-01

    MicroRNAs (miRNAs) regulate gene expression by binding mRNA and inhibiting translation and/or inducing degradation of the associated transcripts. Expression levels of miRNAs have been shown to be altered in response to environmental toxicants, thus impacting cellular function and influencing disease risk. Transcription factors (TFs) are known to be altered in response to environmental toxicants and play a critical role in the regulation of miRNA expression. To date, environmentally-responsive TFs that are important for regulating miRNAs remain understudied. In a state-of-the-art analysis, we utilized an in silico bioinformatic approach to characterize potential transcriptional regulators of environmentally-responsive miRNAs. Using the miRStart database, genomic sequences of promoter regions for all available human miRNAs (n = 847) were identified and promoter regions were defined as − 1000/+500 base pairs from the transcription start site. Subsequently, the promoter region sequences of environmentally-responsive miRNAs (n = 128) were analyzed using enrichment analysis to determine overrepresented TF binding sites (TFBS). While most (56/73) TFs differed across environmental contaminants, a set of 17 TFs was enriched for promoter binding among miRNAs responsive to numerous environmental contaminants. Of these, one TF was common to miRNAs altered by the majority of environmental contaminants, namely SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 3 (SMARCA3). These identified TFs represent candidate common transcriptional regulators of miRNAs perturbed by environmental toxicants. - Highlights: • Transcription factors that regulate environmentally-modulated miRNA expression are understudied • Transcription factor binding sites (TFBS) located within DNA promoter regions of miRNAs were identified. • Specific transcription factors may serve as master regulators of environmentally-mediated microRNA expression.

  5. Environmental contaminants and microRNA regulation: Transcription factors as regulators of toxicant-altered microRNA expression

    International Nuclear Information System (INIS)

    Sollome, James; Martin, Elizabeth; Sethupathy, Praveen; Fry, Rebecca C.

    2016-01-01

    MicroRNAs (miRNAs) regulate gene expression by binding mRNA and inhibiting translation and/or inducing degradation of the associated transcripts. Expression levels of miRNAs have been shown to be altered in response to environmental toxicants, thus impacting cellular function and influencing disease risk. Transcription factors (TFs) are known to be altered in response to environmental toxicants and play a critical role in the regulation of miRNA expression. To date, environmentally-responsive TFs that are important for regulating miRNAs remain understudied. In a state-of-the-art analysis, we utilized an in silico bioinformatic approach to characterize potential transcriptional regulators of environmentally-responsive miRNAs. Using the miRStart database, genomic sequences of promoter regions for all available human miRNAs (n = 847) were identified and promoter regions were defined as − 1000/+500 base pairs from the transcription start site. Subsequently, the promoter region sequences of environmentally-responsive miRNAs (n = 128) were analyzed using enrichment analysis to determine overrepresented TF binding sites (TFBS). While most (56/73) TFs differed across environmental contaminants, a set of 17 TFs was enriched for promoter binding among miRNAs responsive to numerous environmental contaminants. Of these, one TF was common to miRNAs altered by the majority of environmental contaminants, namely SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 3 (SMARCA3). These identified TFs represent candidate common transcriptional regulators of miRNAs perturbed by environmental toxicants. - Highlights: • Transcription factors that regulate environmentally-modulated miRNA expression are understudied • Transcription factor binding sites (TFBS) located within DNA promoter regions of miRNAs were identified. • Specific transcription factors may serve as master regulators of environmentally-mediated microRNA expression

  6. Justice in the Air: Tracking Toxic Pollution from America's Industries and Companies to Our States, Cities, and Neighborhoods

    OpenAIRE

    Michael Ash; James Boyce; Grace Chang; Justin Scoggins; Manuel Pastor

    2009-01-01

    This new environmental justice study, (co-authored by PERI’s James Boyce, Michael Ash, & Grace Chang, along with Manuel Pastor, Justin Scoggins, & Jennifer Tran of the Program for Environmental and Regional Equity at the University of Southern California) examines not only who receives the disproportionate share of toxic air releases -- low-income communities and people of color -- but who is releasing them. Justice in the Air: Tracking Toxic Pollution from America's Industries and Companies ...

  7. A comprehensive study of the toxicity of natural multi-contaminated sediments: New insights brought by the use of a combined approach using the medaka embryo-larval assay and physico-chemical analyses.

    Science.gov (United States)

    Barjhoux, Iris; Clérandeau, Christelle; Menach, Karyn Le; Anschutz, Pierre; Gonzalez, Patrice; Budzinski, Hélène; Morin, Bénédicte; Baudrimont, Magalie; Cachot, Jérôme

    2017-08-01

    Sediment compartment is a long term sink for pollutants and a secondary source of contamination for aquatic species. The abiotic factors controlling the bioavailability and thus the toxicity of complex mixtures of pollutants accumulated in sediments are poorly documented. To highlight the different factors influencing sediment toxicity, we identified and analyzed the physico-chemical properties, micro-pollutant contents, and toxicity level of six contrasted sediments in the Lot-Garonne continuum. Sediment toxicity was evaluated using the recently described Japanese medaka (Oryzias latipes) embryo-larval assay with direct exposure to whole sediment (MELAc). Multiple toxicity endpoints including embryotoxicity, developmental defects and DNA damage were analyzed in exposed embryos. Chemical analyses revealed significant variations in the nature and contamination profile of sediments, mainly impacted by metallic trace elements and, unexpectedly, polycyclic aromatic hydrocarbons. Exposure to sediments induced different toxic impacts on medaka early life stages when compared with the reference site. Principal component analysis showed that the toxic responses following exposure to sediments from the Lot River and its tributary were associated with micro-pollutant contamination: biometric measurements, hatching success, genotoxicity, craniofacial deformities and yolk sac malabsorption were specifically correlated to metallic and organic contaminants. Conversely, the main biological responses following exposure to the Garonne River sediments were more likely related to their physico-chemical properties than to their contamination level. Time to hatch, cardiovascular injuries and spinal deformities were correlated to organic matter content, fine particles and dissolved oxygen levels. These results emphasize the necessity of combining physico-chemical analysis of sediment with toxicity assessment to accurately evaluate the environmental risks associated with sediment

  8. 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

    ventilated room, the renormalization group based k-ε model, together with carbon dioxide used as a tracer, is chosen to reveal this air cross-contamination. The simulation results are in agreement with our prior on-site tracer-gas measurements, revealing that the windows flush with a flat fa ade can...... 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....... 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...

  9. Forced-air warming blowers: An evaluation of filtration adequacy and airborne contamination emissions in the operating room.

    Science.gov (United States)

    Albrecht, Mark; Gauthier, Robert L; Belani, Kumar; Litchy, Mark; Leaper, David

    2011-05-01

    Forced-air warming (FAW) is widely used to prevent hypothermia during surgical procedures. The airflow from these blowers is often vented near the operative site and should be free of contaminants to minimize the risk of surgical site infection. Popular FAW blowers contain a 0.2-μm rated intake filter to reduce these risks. However, there is little evidence that the efficiency of the intake filter is adequate to prevent airborne contamination emissions or protect the internal air path from microbial contamination buildup. Five new intake filters were obtained directly from the manufacturer (Bair Hugger 505, model 200708D; Arizant Healthcare, Eden Prairie, MN), and 5 model 200708C filters currently in hospital use were removed from FAW devices. The retention efficiency of these filters was assessed using a monodisperse sodium chloride aerosol. In the same hospitals, internal air path surface swabs and hose outlet particle counts were performed on 52 forced-air warming devices (all with the model 200708C filter) to assess internal microbial buildup and airborne contamination emissions. Intake filter retention efficiency at 0.2 μm was 93.8% for the 200708C filter and 61.3% at for the 200708D filter. The 200708D filter obtained directly from the manufacturer has a thinner filtration media than the 200708C filter in current hospital use, suggesting that the observed differences in retention efficiency were due to design changes. Fifty-eight percent of the FAW blowers evaluated were internally generating and emitting airborne contaminants, with microorganisms detected on the internal air path surfaces of 92.3% of these blowers. Isolates of Staphylococcus aureus, coagulase-negative Staphylococcus, and methicillin-resistant S aureus were detected in 13.5%, 3.9%, and 1.9% of FAW blowers, respectively. The design of popular FAW devices using the 200708C filter was found to be inadequate for preventing the internal buildup and emission of microbial contaminants into the

  10. Microbial Air Contamination in Indoor and Outdoor Environment of Pig Farms

    Directory of Open Access Journals (Sweden)

    Silvana Popescu

    2014-05-01

    Full Text Available Ensuring a good air quality in pig farms is important for the health of animals and human workers. The aim of this study was the assessment of the microbiological quality of the air inside the pig houses and outside of these. The study was accomplished in two pig-fattening farms in Cluj County. The microbiological air quality was assessed in the cold and warm season, by determination of the total counts of mesophilic bacteria, staphylococci, streptococci, gram-negative bacteria and fungi. The bacterial and fungal counts varied in the air of the investigated farms. In relation to the season the mean counts of bacteria and fungi were significantly higher (P 0.05 were found between the values of the parameters determined from the indoor air and those obtained outside, from a distance of 5 m from the pig houses. The numbers of the bacteria and fungi in the outdoor air lowered as the distance from the farms increased, the differences being significant at 25 and 50 m (P < 0.05. The results of the study show a high bacterial contamination of the indoor and outdoor air of the pig farms.

  11. Measurement of air contamination in different wards of public sector hospital, Sukkur.

    Science.gov (United States)

    Memon, Badaruddin AllahDino; Bhutto, Gul Hassan; Rizvi, Wajid Hussain

    2016-11-01

    The aim of this study was to evaluate and assess the index of bacterial contamination in different wards of the Public Sector Hospital of Sukkur (Teaching) Pakistan; whether or not the air contamination was statistically different from the acceptable level using active and passive sampling. In addition to this main hypothesis, other investigations included: occurrence of the most common bacteria, whether or not the bacterial contamination in the wards was a persistent problem and identification of the effective antibiotics against the indentified bacteria. The evidence sought based on the One Sample T test suggests that there is a (statistically) significant difference between the observed (higher) than the acceptance level (pcontamination problem was persistent as there was no significant difference among observed contamination of all three visits at (p>0.01) and the result of antibiotic susceptibility test highlights sensitivity and resistance level of antibiotics for the indentified bacteria.

  12. Validating potential toxicity assays to assess petroleum hydrocarbon toxicity in polar soil.

    Science.gov (United States)

    Harvey, Alexis Nadine; Snape, Ian; Siciliano, Steven Douglas

    2012-02-01

    Potential microbial activities are commonly used to assess soil toxicity of petroleum hydrocarbons (PHC) and are assumed to be a surrogate for microbial activity within the soil ecosystem. However, this assumption needs to be evaluated for frozen soil, in which microbial activity is limited by liquid water (θ(liquid)). Influence of θ(liquid) on in situ toxicity was evaluated and compared to the toxicity endpoints of potential microbial activities using soil from an aged diesel fuel spill at Casey Station, East Antarctica. To determine in situ toxicity, gross mineralization and nitrification rates were determined by the stable isotope dilution technique. Petroleum hydrocarbon-contaminated soil (0-8,000 mg kg(-1)), packed at bulk densities of 1.4, 1.7, and 2.0 g cm(-3) to manipulate liquid water content, was incubated at -5°C for one, two, and three months. Although θ(liquid) did not have a significant effect on gross mineralization or nitrification, gross nitrification was sensitive to PHC contamination, with toxicity decreasing over time. In contrast, gross mineralization was not sensitive to PHC contamination. Toxic response of gross nitrification was comparable to potential nitrification activity (PNA) with similar EC25 (effective concentration causing a 25% effect in the test population) values determined by both measurement endpoints (400 mg kg(-1) for gross nitrification compared to 200 mg kg(-1) for PNA), indicating that potential microbial activity assays are good surrogates for in situ toxicity of PHC contamination in polar regions. Copyright © 2011 SETAC.

  13. Air toxics concentrations, source identification, and health risks: An air pollution hot spot in southwest Memphis, TN

    Science.gov (United States)

    Jia, Chunrong; Foran, Jeffery

    2013-12-01

    Southwest Memphis is a residential region surrounded by fossil fuel burning, steel, refining, and food processing industries, and considerable mobile sources whose emissions may pose adverse health risks to local residents. This study characterizes cancer and non-cancer risks resulting from exposure to ambient air toxics in southwest Memphis. Air toxics samples were collected at a central location every 6 days from June 5, 2008 to January 8, 2010. Volatile organic compounds (VOCs) were collected in evacuated stainless-steel canisters and aldehydes by DNPH cartridges, and samples were analyzed for 73 target compounds. A total of 60 compounds were detected and 39 were found in over 86% of the samples. Mean concentrations of many compounds were higher than those measured in many industrial communities throughout the U.S. The cumulative cancer risk associated with exposure to 13 carcinogens found in southwest Memphis air was 2.3 × 10-4, four times higher than the national average of 5.0 × 10-5. Three risk drivers were identified: benzene, formaldehyde, and acrylonitrile, which contributed 43%, 19%, and 14% to the cumulative risk, respectively. This is the first field study to confirm acrylonitrile as a potential risk driver. Mobile, secondary, industrial, and background sources contributed 57%, 24%, 14%, and 5% of the risk, respectively. The results of this study indicate that southwest Memphis, a region of significant income, racial, and social disparities, is also a region under significant environmental stress compared with surrounding areas and communities.

  14. Calculation of conversion coefficients using Chinese adult reference phantoms for air submersion and ground contamination.

    Science.gov (United States)

    Lu, Wei; Qiu, Rui; Wu, Zhen; Li, Chunyan; Yang, Bo; Liu, Huan; Ren, Li; Li, Junli

    2017-03-21

    The effective and organ equivalent dose coefficients have been widely used to provide assessment of doses received by adult members of the public and by workers exposed to environmental radiation from nuclear facilities under normal or accidental situations. Advancements in phantom types, weighting factors, decay data, etc, have led to the publication of newer results in this regard. This paper presents a new set of conversion coefficients for air submersion and ground contamination (with the use of Geant4) for photons from 15 keV to 10 MeV using the Chinese and International Commission on Radiological Protection (ICRP) adult reference male and female phantoms. The radiation fields, except for energy spectrum at low energies, were validated by the data obtained from the Monte Carlo code YURI. The effective dose coefficients of monoenergetic photons, obtained for the ICRP adult reference phantoms, agree well with recently published data for air submersion and ground contamination with a plane source at a depth of 0.5 g cm -2 in soil, but an average difference of 36.5% is observed for ground surface contamination with the abovementioned radiation field. The average differences in organ equivalent dose coefficients between the Chinese and the ICRP adult reference phantoms are within 6% for most organs, but noticeable differences of up to 70% or even higher are found at photon energies below 30 keV under air submersion. The effective dose coefficients obtained with the Chinese adult reference phantoms are greater than those of the ICRP adult reference phantoms above 30 keV and 0.5 MeV for ground contamination and air submersion, respectively; the average differences from the Chinese adult reference phantoms are about 3.6% and 0.4% in the whole energy range with maximum differences of 31.8% and 27.6% at 15 keV for air submersion and ground contamination respectively. These differences are attributed to anatomical discrepancies in overlying tissue mass of an

  15. Air-sampling inlet contamination by aircraft emissions on the NASA CV-990 aircraft

    Science.gov (United States)

    Condon, E. P.; Vedder, J. F.

    1984-01-01

    Results of an experimental investigation of the contamination of air sampling inlets by aircraft emissions from the NASA CV-990 research aircraft are presented. This four-engine jet aircraft is a NASA facility used for many different atmospheric and meteorological experiments, as well as for developing spacecraft instrumentation for remote measurements. Our investigations were performed to provide information on which to base the selection of sampling locations for a series of multi-instrument missions for measuring tropospheric trace gases. The major source of contamination is the exhaust from the jet engines, which generate many of the same gases that are of interest in atmospheric chemistry, as well as other gases that may interfere with sampling measurements. The engine exhaust contains these gases in mixing ratios many orders of magnitude greater than those that occur in the clean atmosphere which the missions seek to quantify. Pressurized samples of air were collected simultaneously from a scoop located forward of the engines to represent clean air and from other multiport scoops at various aft positions on the aircraft. The air samples were analyzed in the laboratory by gas chromatography for carbon monoxide, an abundant combustion by-product. Data are presented for various scoop locations under various flight conditions.

  16. Engineered Nanoparticles as Potential Food Contaminants and Their Toxicity to Caco-2 Cells.

    Science.gov (United States)

    Mao, Xiaomo; Nguyen, Trang H D; Lin, Mengshi; Mustapha, Azlin

    2016-08-01

    Engineered nanoparticles (ENPs), such as metallic or metallic oxide nanoparticles (NPs), have gained much attention in recent years. Increasing use of ENPs in various areas may lead to the release of ENPs into the environment and cause the contamination of agricultural and food products by ENPs. In this study, we selected two important ENPs (zinc oxide [ZnO] and silver [Ag] NPs) as potential food contaminants and investigated their toxicity via an in vitro model using Caco-2 cells. The physical properties of ENPs and their effects on Caco-2 cells were characterized by electron microscopy and energy dispersive X-ray spectroscopic (EDS) techniques. Results demonstrate that a significant inhibition of cell viability was observed after a 24-h of exposure of Caco-2 cells to 3-, 6-, and 12-mM ZnO NPs or 0.5-, 1.5-, and 3-mM Ag NPs. The noticeable changes of cells include the alteration in cell shape, abnormal nuclear structure, membrane blebbing, and cytoplasmic deterioration. The toxicity of ZnO NPs, but not that of Ag NPs after exposure to simulated gastric fluid, significantly decreased. Scanning transmission electron microscopy shows that ZnO and Ag NPs penetrated the membrane of Caco-2 cells. EDS results also confirm the presence of NPs in the cytoplasm of the cells. This study demonstrates that ZnO and Ag NPs have cytotoxic effects and can inhibit the growth of Caco-2 cells. © 2016 Institute of Food Technologists®

  17. The Calculation of Self-Disposal Date by Analyzing the Radioactive Contamination of Air Filters Disused in Radioisotope Production Facility

    International Nuclear Information System (INIS)

    Kim, Sung Ho; Lee, Bu Hyung; Kwon, Soo Il

    2016-01-01

    The aim of the study is to decrease the diffusion of air contamination which occurred in radiation work places handle radioisotope under the permissible level. Accordingly, we replaced used air filter with a new one at the appropriate time , and computed disposal dates for disposing used air filters by calculate radioactive contamination. Air filter contaminated by radioactivity is possible to be self-disposed on condition that all detected nuclides is below permissible level according to Nuclear Safety and Security Commission (NSSC) notification No. 2014-003. Radioisotope, produced by 30, 50 MeV cyclotron and carried from other institutions, is used to treat patients, diagnose diseases, and research technology in Korea Institute of Radiological and Medical Sciences (KIRAMS). With unsealed sources generate radioactive contamination in air, it is important to use fume hood or hot cell. The accurate date needs to be calculated by the equation for calculation of self disposal date. If disposal date is in 1000 days, disposal for external institution is required. With increasing the number of medical institute which was related to use the radioisotopes, the importance of radioactive safety management was increased. As disposing radioactive waste, in particular, is the procedure of inspecting for releasing radioactive waste to outside, appropriate action and continuous research are required at a radioactive safety management.

  18. (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.

  19. Heavy metals in contaminated environment: Destiny of secondary metabolite biosynthesis, oxidative status and phytoextraction in medicinal plants.

    Science.gov (United States)

    Asgari Lajayer, Behnam; Ghorbanpour, Mansour; Nikabadi, Shahab

    2017-11-01

    Contamination of soils, water and air with toxic heavy metals by various human activities is a crucial environmental problem in both developing and developed countries. Heavy metals could be introduced into medicinal plant products through contaminated environment (soil, water and air resources) and/or poor production practices. Growing of medicinal plants in heavy metal polluted environments may eventually affect the biosynthesis of secondary metabolites, causing significant changes in the quantity and quality of these compounds. Certain medicinal and aromatic plants can absorb and accumulate metal contaminants in the harvestable foliage and, therefore, considered to be a feasible alternative for remediation of polluted sites without any contamination of essential oils. Plants use different strategies and complex arrays of enzymatic and non-enzymatic anti-oxidative defense systems to cope with overproduction of ROS causes from the heavy metals entered their cells through foliar and/or root systems. This review summarizes the reports of recent investigations involving heavy metal accumulation by medicinal plants and its effects on elicitation of secondary metabolites, toxicity and detoxification pathways, international standards regarding in plants and plant-based products, and human health risk assessment of heavy metals in soil-medicinal plants systems. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Compressed breathing air - the potential for evil from within.

    Science.gov (United States)

    Millar, Ian L; Mouldey, Peter G

    2008-06-01

    Human underwater activities rely on an adequate supply of breathable compressed gas, usually air, free from contaminants that could cause incapacitation underwater or post-dive or longer-term health effects. Potentially fatal but well-known hazards are hypoxia secondary to steel cylinder corrosion and carbon monoxide (CO) poisoning due to contaminated intake air. Another phenomenon may be behind some previously unexplained episodes of underwater incapacitation and perhaps death: low-level CO poisoning and/or the effects of gaseous contaminants generated within the compressor, including toluene and other volatile compounds. Many low molecular weight volatile contaminants are anaesthetic and will be potentiated by pressure and nitrogen narcosis. In sub-anaesthetic doses, impaired judgement, lowered seizure threshold and sensitisation of the heart to arrhythmias may occur. Toxic compounds can be volatilised from some compressor oils, especially mineral oils, in overheated compressors, or be created de novo under certain combinations of temperature, humidity and pressure, perhaps catalysed by metal traces from compressor wear and tear. Most volatiles can be removed by activated carbon filtration but many filters are undersized and may overload in hot, moist conditions and with short dwell times. A compressor that passes normal testing could contaminate one or more cylinders after heating up and then return to producing clean air as the filters dry and the systems cool. The scope of this problem is very unclear as air quality is tested infrequently and often inadequately, even after fatalities. More research is needed as well as better education regarding the safe operation and limitations of high-pressure breathing air compressors.

  1. Toxicokinetics of Zn and Cd in the earthworm Eisenia andrei exposed to metal-contaminated soils under different combinations of air temperature and soil moisture content.

    Science.gov (United States)

    González-Alcaraz, M Nazaret; Loureiro, Susana; van Gestel, Cornelis A M

    2018-04-01

    This study evaluated how different combinations of air temperature (20 °C and 25 °C) and soil moisture content (50% and 30% of the soil water holding capacity, WHC), reflecting realistic climate change scenarios, affect the bioaccumulation kinetics of Zn and Cd in the earthworm Eisenia andrei. Earthworms were exposed for 21 d to two metal-contaminated soils (uptake phase), followed by 21 d incubation in non-contaminated soil (elimination phase). Body Zn and Cd concentrations were checked in time and metal uptake (k 1 ) and elimination (k 2 ) rate constants determined; metal bioaccumulation factor (BAF) was calculated as k 1 /k 2 . Earthworms showed extremely fast uptake and elimination of Zn, regardless of the exposure level. Climate conditions had no major impacts on the bioaccumulation kinetics of Zn, although a tendency towards lower k 1 and k 2 values was observed at 25 °C + 30% WHC. Earthworm Cd concentrations gradually increased with time upon exposure to metal-contaminated soils, especially at 50% WHC, and remained constant or slowly decreased following transfer to non-contaminated soil. Different combinations of air temperature and soil moisture content changed the bioaccumulation kinetics of Cd, leading to higher k 1 and k 2 values for earthworms incubated at 25 °C + 50% WHC and slower Cd kinetics at 25 °C + 30% WHC. This resulted in greater BAFs for Cd at warmer and drier environments which could imply higher toxicity risks but also of transfer of Cd within the food chain under the current global warming perspective. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Use of dust fall filters as passive samplers for metal concentrations in air for communities near contaminated mine tailings.

    Science.gov (United States)

    Beamer, P I; Sugeng, A J; Kelly, M D; Lothrop, N; Klimecki, W; Wilkinson, S T; Loh, M

    2014-05-01

    Mine tailings are a source of metal exposures in many rural communities. Multiple air samples are necessary to assess the extent of exposures and factors contributing to these exposures. However, air sampling equipment is costly and requires trained personnel to obtain measurements, limiting the number of samples that can be collected. Simple, low-cost methods are needed to allow for increased sample collection. The objective of our study was to assess if dust fall filters can serve as passive air samplers and be used to characterize potential exposures in a community near contaminated mine tailings. We placed filters in cylinders, concurrently with active indoor air samplers, in 10 occupied homes. We calculated an estimated flow rate by dividing the mass on each dust fall filter by the bulk air concentration and the sampling duration. The mean estimated flow rate for dust fall filters was significantly different during sampling periods with precipitation. The estimated flow rate was used to estimate metal concentration in the air of these homes, as well as in 31 additional homes in another rural community impacted by contaminated mine tailings. The estimated air concentrations had a significant linear association with the measured air concentrations for beryllium, manganese and arsenic (p passive air sampler is a simple low-cost method to assess potential exposures near contaminated mining sites.

  3. Assessing the influence of traffic-related air pollution on risk of term low birth weight on the basis of land-use-based regression models and measures of air toxics.

    Science.gov (United States)

    Ghosh, Jo Kay C; Wilhelm, Michelle; Su, Jason; Goldberg, Daniel; Cockburn, Myles; Jerrett, Michael; Ritz, Beate

    2012-06-15

    Few studies have examined associations of birth outcomes with toxic air pollutants (air toxics) in traffic exhaust. This study included 8,181 term low birth weight (LBW) children and 370,922 term normal-weight children born between January 1, 1995, and December 31, 2006, to women residing within 5 miles (8 km) of an air toxics monitoring station in Los Angeles County, California. Additionally, land-use-based regression (LUR)-modeled estimates of levels of nitric oxide, nitrogen dioxide, and nitrogen oxides were used to assess the influence of small-area variations in traffic pollution. The authors examined associations with term LBW (≥37 weeks' completed gestation and birth weight variations) resulted in 2%-5% increased odds per interquartile-range increase in third-trimester benzene, toluene, ethyl benzene, and xylene exposures, with some confidence intervals containing the null value. This analysis highlights the importance of both spatial and temporal contributions to air pollution in epidemiologic birth outcome studies.

  4. Chemical concentrations, exposures, health risks by census tract from National Scale Air Toxics Assessment (NATA)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Chemical concentrations, exposures, health risks by census tract for the United States from National Scale Air Toxics Assessment (NATA). This dataset is associated...

  5. 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.

  6. Traffic flow and microbial air contamination in operating rooms at a major teaching hospital in Ghana.

    Science.gov (United States)

    Stauning, M T; Bediako-Bowan, A; Andersen, L P; Opintan, J A; Labi, A-K; Kurtzhals, J A L; Bjerrum, S

    2018-07-01

    Current literature examining the relationship between door-opening rate, number of people present, and microbial air contamination in the operating room is limited. Studies are especially needed from low- and middle-income countries, where the risk of surgical site infections is high. To assess microbial air contamination in operating rooms at a Ghanaian teaching hospital and the association with door-openings and number of people present. Moreover, we aimed to document reasons for door-opening. We conducted active air-sampling using an MAS 100 ® portable impactor during 124 clean or clean-contaminated elective surgical procedures. The number of people present, door-opening rate and the reasons for each door-opening were recorded by direct observation using pretested structured observation forms. During surgery, the mean number of colony-forming units (cfu) was 328 cfu/m 3 air, and 429 (84%) of 510 samples exceeded a recommended level of 180 cfu/m 3 . Of 6717 door-openings recorded, 77% were considered unnecessary. Levels of cfu/m 3 were strongly correlated with the number of people present (P = 0.001) and with the number of door-openings/h (P = 0.02). In empty operating rooms, the mean cfu count was 39 cfu/m 3 after 1 h of uninterrupted ventilation and 52 (51%) of 102 samples exceeded a recommended level of 35 cfu/m 3 . The study revealed high values of intraoperative airborne cfu exceeding recommended levels. Minimizing the number of door-openings and people present during surgery could be an effective strategy to reduce microbial air contamination in low- and middle-income settings. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  7. Traffic flow and microbial air contamination in operating rooms at a major teaching hospital in Ghana

    DEFF Research Database (Denmark)

    Stauning, M. T.; Bediako-Bowan, A.; Andersen, L. P.

    2018-01-01

    . Aim: To assess microbial air contamination in operating rooms at a Ghanaian teaching hospital and the association with door-openings and number of people present. Moreover, we aimed to document reasons for door-opening. Methods: We conducted active air-sampling using an MAS 100® portable impactor...

  8. 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.

  9. Evaluation of Mobility, Bioavailability and Toxicity of Pb and Cd in Contaminated Soil Using TCLP, BCR and Earthworms

    Science.gov (United States)

    Kede, Maria Luiza F. M.; Correia, Fabio V.; Conceição, Paulo F.; Salles Junior, Sidney F.; Marques, Marcia; Moreira, Josino C.; Pérez, Daniel V.

    2014-01-01

    The objective of the present study was to investigate the reduction of mobility, availability and toxicity found in soil contaminated with lead (Pb) and cadmium (Cd) from Santo Amaro Municipality, Bahia, Brazil using two combined methods, commonly tested separately according to the literature: metal mobilization with phosphates and phytoextraction. The strategy applied was the treatment with two sources of phosphates (separately and mixed) followed by phytoremediation with vetiver grass (Vetiveria zizanioides (L.)). The treatments applied (in triplicates) were: T1—potassium dihydrogen phosphate (KH2PO4); T2—reactive natural phosphate fertilizer (NRP) and; T3—a mixture 1:1 of KH2PO4 and NRP. After this step, untreated and treated soils were planted with vetiver grass. The extraction procedures and assays applied to contaminated soil before and after the treatments included metal mobility test (TCLP); sequential extraction with BCR method; toxicity assays with Eisenia andrei. The soil-to-plant transfer factors (TF) for Pb and Cd were estimated in all cases. All treatments with phosphates followed by phytoremediation reduced the mobility and availability of Pb and Cd, being KH2PO4 (T1) plus phytoremediation the most effective one. Soil toxicity however, remained high after all treatments. PMID:25386955

  10. Evaluation of Mobility, Bioavailability and Toxicity of Pb and Cd in Contaminated Soil Using TCLP, BCR and Earthworms

    Directory of Open Access Journals (Sweden)

    Maria Luiza F. M. Kede

    2014-11-01

    Full Text Available The objective of the present study was to investigate the reduction of mobility, availability and toxicity found in soil contaminated with lead (Pb and cadmium (Cd from Santo Amaro Municipality, Bahia, Brazil using two combined methods, commonly tested separately according to the literature: metal mobilization with phosphates and phytoextraction. The strategy applied was the treatment with two sources of phosphates (separately and mixed followed by phytoremediation with vetiver grass (Vetiveria zizanioides (L.. The treatments applied (in triplicates were: T1—potassium dihydrogen phosphate (KH2PO4; T2—reactive natural phosphate fertilizer (NRP and; T3—a mixture 1:1 of KH2PO4 and NRP. After this step, untreated and treated soils were planted with vetiver grass. The extraction procedures and assays applied to contaminated soil before and after the treatments included metal mobility test (TCLP; sequential extraction with BCR method; toxicity assays with Eisenia andrei. The soil-to-plant transfer factors (TF for Pb and Cd were estimated in all cases. All treatments with phosphates followed by phytoremediation reduced the mobility and availability of Pb and Cd, being KH2PO4 (T1 plus phytoremediation the most effective one. Soil toxicity however, remained high after all treatments.

  11. A study on contaminant transport in indoor air

    International Nuclear Information System (INIS)

    Pujala, Usha; Sen, Soubhadra; Subramanian, V.; Srinivas, C.V.; Baskaran, R.; Venkatraman, B.

    2016-01-01

    In case of an accidental release of radioactive contaminant inside a well-ventilated room, the same will be transported to the different parts of the room due to the circulation of indoor air. To ensure safety of the operating personnel, it is important to identify the ideal locations for keeping the warning alarm systems. To address the problem, a detailed study is required where numerical simulation has to be supported by experimental verification. A computational methodology has already been verified for this purpose (IGC report-no.323). In this work, a study on the transport of an inert aerosol inside a well-ventilated isolated room has been carried out

  12. Removal of Cyclohexane from a Contaminated Air Stream Using a Dense Phase Membrane Bioreactor

    National Research Council Canada - National Science Library

    Roberts, Michael G

    2005-01-01

    The purpose of this research was to determine the ability of a dense phase membrane bioreactor to remove cyclohexane, a volatile organic compound in JP-8 jet fuel, from a contaminated air stream using...

  13. 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

    The level of exposure to human exhaled contaminants in a room depends not only on the air distribution system but also on people’s different positions, the distance between them, people’s activity level and height, direction of exhalation, and the surrounding temperature and temperature gradient...... 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....... 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...

  14. Hazardous Air Pollutants

    Science.gov (United States)

    ... Search Main menu Environmental Topics Air Bed Bugs Chemicals and Toxics Environmental Information by Location Greener Living Health Land, ... regulate toxic air pollutants, also known as air toxics, from categories of industrial facilities in two phases . About Hazardous Air Pollutants ...

  15. 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.

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

    International Nuclear Information System (INIS)

    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 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. Assessment of the environmental microbiological cross contamination following hand drying with paper hand towels or an air blade dryer.

    Science.gov (United States)

    Margas, E; Maguire, E; Berland, C R; Welander, F; Holah, J T

    2013-08-01

    This study compared the potential for cross contamination of the surrounding environment resulting from two different hand-drying methods: paper towels and the use of an air blade dryer. One hundred volunteers for each method washed their hands and dried them using one of the two methods. Bacterial contamination of the surrounding environment was measured using settle plates placed on the floor in a grid pattern, air sampling and surface swabs. Both drying methods produced ballistic droplets in the immediate vicinity of the hand-drying process. The air blade dryer produced a larger number of droplets which were dispersed over a larger area. Settle plates showed increased microbial contamination in the grid squares which were affected by ballistic droplets. Using the settle plates counts, it was estimated that approx. 1.7 × 10(5) cfu more micro-organisms were left on the laboratory floor (total area approx. 17.15 m(2)) after 100 volunteers used an air blade dryer compared to when paper towels were used. The two drying methods led to different patterns of ballistic droplets and levels of microbial contamination under heavy use conditions. Whilst the increase in microbial levels in the environment is not significant if only nonpathogenic micro-organisms are spread, it may increase the risk of pathogen contamination of the environment when pathogens are occasionally present on people's hands. The study suggests that the risk of cross contamination from the washroom users to the environment and subsequent users should be considered when choosing a hand-drying method. The data could potentially give guidance following the selection of drying methods on implementing measures to minimise the risk of cross contamination. © 2013 The Society for Applied Microbiology.

  18. Radiation risks to human health during air pollution from wildfires in contaminated zones

    International Nuclear Information System (INIS)

    Dvornik, A.A.

    2016-01-01

    The results of the investigation of radiation hazard of forest fires in the radioactive contaminated areas are presented in the article. Airborne concentration of Cs 137 produced by the combustion of forest fuel materials with different contamination density can exceed the permissible activity levels of Cs 137 in air. The emission containing radionuclides deposited on the fine aerosol fractions is particularly dangerous. Inhalation of radionuclides can generate additional internal doses both for fire-fighters, near the source of ignition, and for citizens, at a distance from the source. (authors)

  19. Pollution of atmospheric air with toxic and radioactive particulate matter investigated by means of nuclear techniques

    International Nuclear Information System (INIS)

    Jagielak, J.

    1978-01-01

    The application of spectrometric methods of nuclear techniques to the investigations of atmospheric air pollution by toxic and radioactive elements and results of these investigations conducted in the highly industrialized and urbanized regions of Poland have been presented. The method of precipitation of the samples, the measurements and analysis of radiation spectra of alpha and gamma radiation emitted by isotopes present in the samples have been described. The concentrations of toxic metal dust in the air have been evaluated by neutron activation and X-ray fluorescence analysis. Appropriate methods of measurement, calibration of instrument and the discussion of results have been presented. The work presents the results of investigations performed in Siersza within the years 1973-1974 and in Warsaw in the period of 1975-1977, which have permitted to estimate the mean monthly values of concentration in the atmospheric air of the following radioisotopes: 7 Be, 54 Mn, 95 Zr, 103 Ru, 106 Ru, 125 Sb, 131 I, 137 Cs, 140 Ba, 141 Ce, 144 Ce, 226 Ra, Th-nat, U-nat and the following stable elements: Sc, Cr, Fe, Co, Zn, As, Se, Sb, W, Pb. The analysis of changes in concentration of each particular artificial radioisotope in the air for the region of Poland in connection with Chinese nuclear explosions have been given. On the basis of the performed environmental investigations the method of analysis of relations between the concentrations of particular elements present in the dust has been discussed. The applications of this method have been presented. The hazard to the population and the environment caused by the radioactive and toxic dust present in the atmospheric air has been estimated. (author)

  20. Toxicity and elemental composition of particulate matter from outdoor and indoor air of elementary schools in Munich, Germany.

    Science.gov (United States)

    Oeder, S; Dietrich, S; Weichenmeier, I; Schober, W; Pusch, G; Jörres, R A; Schierl, R; Nowak, D; Fromme, H; Behrendt, H; Buters, J T M

    2012-04-01

    Outdoor particulate matter (PM(10)) is associated with detrimental health effects. However, individual PM(10) exposure occurs mostly indoors. We therefore compared the toxic effects of classroom, outdoor, and residential PM(10). Indoor and outdoor PM(10) was collected from six schools in Munich during teaching hours and in six homes. Particles were analyzed by scanning electron microscopy and X-ray spectroscopy (EDX). Toxicity was evaluated in human primary keratinocytes, lung epithelial cells and after metabolic activation by several human cytochromes P450. We found that PM(10) concentrations during teaching hours were 5.6-times higher than outdoors (117 ± 48 μg/m(3) vs. 21 ± 15 μg/m(3), P particle number), organic (29%, probably originating from human skin), and Ca-carbonate particles (12%, probably originating from paper). Outdoor PM contained more Ca-sulfate particles (38%). Indoor PM at 6 μg/cm(2) (10 μg/ml) caused toxicity in keratinocytes and in cells expressing CYP2B6 and CYP3A4. Toxicity by CYP2B6 was abolished with the reactive oxygen species scavenger N-acetylcysteine. We concluded that outdoor PM(10) and indoor PM(10) from homes were devoid of toxicity. Indoor PM(10) was elevated, chemically different and toxicologically more active than outdoor PM(10). Whether the effects translate into a significant health risk needs to be determined. Until then, we suggest better ventilation as a sensible option. Indoor air PM(10) on an equal weight base is toxicologically more active than outdoor PM(10). In addition, indoor PM(10) concentrations are about six times higher than outdoor air. Thus, ventilation of classrooms with outdoor air will improve air quality and is likely to provide a health benefit. It is also easier than cleaning PM(10) from indoor air, which has proven to be tedious. © 2011 John Wiley & Sons A/S.

  1. 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.

  2. Control of Toxic Chemicals in Puget Sound, Phase 3: Study Of Atmospheric Deposition of Air Toxics to the Surface of Puget Sound

    Science.gov (United States)

    2007-01-01

    http://www.ecy.wa.gov/ biblio /0810084.html Environmental Protection Agency (EPA) (1991). Evaluation of the Atmospheric Deposition of Toxic Contaminants...Washington State Department of Ecology, Olympia, WA. Publication Number: 09-03- 015. http://www.ecy.wa.gov/ biblio /0903015.html. Pelletier, G...Washington http://www.ecy.wa.gov/ biblio /0810084.html Fabbri, D., Marynowski, L., Fabianska, M.J., Zaton, M. Simoneit, B.R.T. (2008). Levoglucosan and

  3. Remediation of lead-contaminated soil with non-toxic biodegradable natural ligands extracted from soybean.

    Science.gov (United States)

    Lee, Yong-Woo; Kim, Chulsung

    2012-01-01

    Bench-scale soil washing studies were performed to evaluate the potential application of non-toxic, biodegradable extracted soybean-complexing ligands for the remediation of lead-contaminated soils. Results showed that, with extracted soybean-complexing ligands, lead solubility extensively increased when pH of the solution was higher than 6, and approximately 10% (500 mg/kg) of lead was removed from a rifle range soil. Two potential primary factors controlling the effectiveness of lead extraction from lead-contaminated soils with natural ligands are adsorption of extracted aqueous lead ions onto the ground soybean and the pH of the extraction solution. More complexing ligands were extracted from the ground soybean as the reaction pH increased. As a result, significantly higher lead extraction efficiency was observed under basic environments. In addition, less adsorption onto soybean was observed when the pH of the solution was higher than 7. Among two available Lewis base functional groups in the extracted soybean-complexing ligands such as carboxylate and the alpha-amino functional groups, the non-protonated alpha-amino functional groups may play an important role for the dissolution of lead from lead-contaminated soil through the formation of soluble lead--ligand complexes.

  4. Ground-water contamination at Wurtsmith Air Force Base, Michigan

    Science.gov (United States)

    Stark, J.R.; Cummings, T.R.; Twenter, F.R.

    1983-01-01

    A sand and gravel aquifer of glacial origin underlies Wurtsmith Air Force Base in northeastern lower Michigan. The aquifer overlies a thick clay layer at an average depth of 65 feet. The water table is about 10 feet below land surface in the western part of the Base and about 25 feet below land surface in the eastern part. A ground-water divide cuts diagonally across the Base from northwest to southeast. South of the divide, ground water flows to the Au Sable River; north of the divide, it flows to Van Etten Creek and Van Etten Lake. Mathematical models were used to aid in calculating rates of groundwater flow. Rates range from about 0.8 feet per day in the eastern part of the Base to about 0.3 feet per day in the western part. Models also were used as an aid in making decisions regarding purging of contaminated water from the aquifer. In 1977, trichloroethylene was detected in the Air Force Base water-supply system. It had leaked from a buried storage tank near Building 43 in the southeastern part of the Base and moved northeastward under the influence of the natural ground-water gradient and the pumping of Base water-supply wells. In the most highly contaminated part of the plume, concentrations are greater than 1,000 micrograms per liter. Current purge pumping is removing some of the trichloroethylene, and seems to have arrested its eastward movement. Pumping of additional purge wells could increase the rate of removal. Trichloroethylene has also been detected in ground water in the vicinity of the Base alert apron, where a plume from an unknown source extends northeastward off Base. A smaller, less well-defined area of contamination also occurs just north of the larger plume. Trichloroethylene, identified near the waste-treatment plant, seepage lagoons, and the northern landfill area, is related to activities and operations in these areas. Dichloroethylene and trichloroethylene occur in significant quantities westward of Building 43, upgradient from the major

  5. 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

  6. Mobile laminar air flow screen for additional operating room ventilation: reduction of intraoperative bacterial contamination during total knee arthroplasty.

    Science.gov (United States)

    Sossai, D; Dagnino, G; Sanguineti, F; Franchin, F

    2011-12-01

    Surgical site infections are important complications in orthopedic surgery. A mobile laminar air flow (LAF) screen could represent a useful addition to an operating room (OR) with conventional turbulent air ventilation (12.5 air changes/h), as it could decrease the bacterial count near the operating field. The purpose of this study was to evaluate LAF efficacy at reducing bacterial contamination in the surgical area during 34 total knee arthroplasties (TKAs). The additional unit was used in 17 operations; the LAF was positioned beside the operating table between two of the surgeons, with the air flow directed towards the surgical area (wound). The whole team wore conventional OR clothing and the correct hygiene procedures and rituals were used. Bacterial air contamination (CFU/m(3)) was evaluated in the wound area in 17 operations with the LAF unit and 17 without the LAF unit. The LAF unit reduced the mean bacterial count in the wound area from 23.5 CFU/m(3) without the LAF to 3.5 CFU/m(3) with the LAF (P contamination of the wound area significantly decreased to below the accepted level for an ultraclean OR, preventing SSI infections.

  7. Air sampling methods to evaluate microbial contamination in operating theatres: results of a comparative study in an orthopaedics department.

    Science.gov (United States)

    Napoli, C; Tafuri, S; Montenegro, L; Cassano, M; Notarnicola, A; Lattarulo, S; Montagna, M T; Moretti, B

    2012-02-01

    To evaluate the level of microbial contamination of air in operating theatres using active [i.e. surface air system (SAS)] and passive [i.e. index of microbial air contamination (IMA) and nitrocellulose membranes positioned near the wound] sampling systems. Sampling was performed between January 2010 and January 2011 in the operating theatre of the orthopaedics department in a university hospital in Southern Italy. During surgery, the mean bacterial loads recorded were 2232.9 colony-forming units (cfu)/m(2)/h with the IMA method, 123.2 cfu/m(3) with the SAS method and 2768.2 cfu/m(2)/h with the nitrocellulose membranes. Correlation was found between the results of the three methods. Staphylococcus aureus was detected in 12 of 60 operations (20%) with the membranes, five (8.3%) operations with the SAS method, and three operations (5%) with the IMA method. Use of nitrocellulose membranes placed near a wound is a valid method for measuring the microbial contamination of air. This method was more sensitive than the IMA method and was not subject to any calibration bias, unlike active air monitoring systems. Copyright © 2011 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  8. Estimating children's exposure to toxic elements in contaminated toys and children's jewelry via saliva mobilization.

    Science.gov (United States)

    Guney, Mert; Nguyen, Alain; Zagury, Gerald J

    2014-09-19

    Children's potential for exposure to potentially toxic elements in contaminated jewelry and toys via mouth contact has not yet been fully evaluated. Various toys and jewelry (metallic toys and jewelry [MJ], plastic toys, toys with paint or coating, and brittle/pliable toys; n = 32) were tested using the saliva extraction (mouthing) compartment of the DIN and RIVM bioaccessibility protocols to assess As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, Sb, and Se mobilization via saliva. Total concentrations of As, Cd, Cu, Ni, Pb, and Sb were found elevated in analyzed samples. Four metals were mobilized to saliva from 16 MJ in significant quantities (>1 μg for highly toxic Cd and Pb, >10 μg for Cu and Ni). Bioaccessible concentrations and hazard index values for Cd exceeded limit values, for young children between 6 mo- and 3 yr-old and according to both protocols. Total and bioaccessible metal concentrations were different and not always correlated, encouraging the use of bioaccessibility for more accurate hazard assessments. Bioaccessibility increased with increasing extraction time. Overall, the risk from exposure to toxic elements via mouthing was high only for Cd and for MJ. Further research on children's exposure to toxic elements following ingestion of toy or jewelry material is recommended.

  9. [Contamination levels to room air arising from the use of 99mTc-gas and prevention from the contamination].

    Science.gov (United States)

    Komatani, A; Akutsu, T; Yamaguchi, K; Onodera, Y; Manaka, Y; Takahashi, K

    1996-04-01

    99mTc-gas (TECHNEGAS) is a 99mTc-labeled micro-aerosol which is considered to have different behavior from 133Xe or 81mKr gas. In order to estimate contamination levels to room air arising from the use of 99mTc-gas, filtered expired air during administration and 1, 2, 3, 5, 10 min after the administration were collected in each polyethylene bag. Radioactivities of the polyethylene bags, used filter and the lung were measured with 3-head scintillation camera. The activity of the expired air diminished within 6-10 min and about 5% of whole discharged 99mTc-gas was released to room air. The activity of the used filter was two times of the lung. According to these results, it is recommended that the 99mTc-gas may be administrated in a exclusive room. The administrated patient and used filter must be remain in the exclusive room.

  10. 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.

  11. Source water assessment and nonpoint sources of acutely toxic contaminants: A review of research related to survival and transport of Cryptosporidium parvum

    Science.gov (United States)

    Walker, Mark J.; Montemagno, Carlo D.; Jenkins, Michael B.

    1998-12-01

    Amendments to the Safe Drinking Water Act (PL-930123) in 1996 required that public water supply managers identify potential sources of contamination within contributing areas. Nonpoint sources of acutely toxic microbial contaminants, such as Cryptosporidium parvum, challenge current approaches to source identification and management as a first step toward developing management plans for public water supply protection. Little may be known about survival and transport in the field environment, prescribed practices may not be designed to manage such substances, and infective stages may be present in vast numbers and may resist water treatment and disinfection processes. This review summarizes research related to survival and transport of C. parvum oocysts, as an example of an acutely toxic contaminant with nonpoint sources in animal agriculture. It discusses ∥1) significance of infected domesticated animals as potential sources of C. parvum, (2) laboratory and field studies of survival and transport, and (3) approaches to source control in the context of public health protection.

  12. Contaminated fluid filtration plant using pneumatically renewable granulated material

    International Nuclear Information System (INIS)

    Lucas, J.-C.; Messirejean, Pierre.

    1980-01-01

    This invention concerns a plant for the filtration of a contaminated fluid flow using a granulated material capable of absorbing or adsorbing the contaminants. This plant includes a filtration box within which there is at least one appreciably vertical filtering bed filled with the material and crossed by the fluid flow, loading and discharge compartments respectively located at the top and bottom of the box, each in communication with the filtering bed and an air-actuated transfer system for loading and discharging this bed through these compartments. Facilities of this kind are used mainly in the nuclear and chemical engineering industries to rid their waste of radio-iodines, generally constituted by elementary iodine and methyl iodide, or of toxic gases that contaminate them. The granulated material, whose job it is to trap these contaminants by adsorption or absorption, is generally composed of active carbon or zeolites whose utilisation time is limited [fr

  13. A prospective survey of air and surface fungal contamination in a medical mycology laboratory at a tertiary care university hospital.

    Science.gov (United States)

    Sautour, Marc; Dalle, Frédéric; Olivieri, Claire; L'ollivier, Coralie; Enderlin, Emilie; Salome, Elsa; Chovelon, Isabelle; Vagner, Odile; Sixt, Nathalie; Fricker-Pap, Véronique; Aho, Serge; Fontaneau, Olivier; Cachia, Claire; Bonnin, Alain

    2009-04-01

    Invasive filamentous fungi infections resulting from inhalation of mold conidia pose a major threat in immunocompromised patients. The diagnosis is based on direct smears, cultural symptoms, and culturing fungi. Airborne conidia present in the laboratory environment may cause contamination of cultures, resulting in false-positive diagnosis. Baseline values of fungal contamination in a clinical mycology laboratory have not been determined to date. A 1-year prospective survey of air and surface contamination was conducted in a clinical mycology laboratory during a period when large construction projects were being conducted in the hospital. Air was sampled with a portable air system impactor, and surfaces were sampled with contact Sabouraud agar plates. The collected data allowed the elaboration of Shewhart graphic charts. Mean fungal loads ranged from 2.27 to 4.36 colony forming units (cfu)/m(3) in air and from 0.61 to 1.69 cfu/plate on surfaces. Strict control procedures may limit the level of fungal contamination in a clinical mycology laboratory even in the context of large construction projects at the hospital site. Our data and the resulting Shewhart graphic charts provide baseline values to use when monitoring for inappropriate variations of the fungal contamination in a mycology laboratory as part of a quality assurance program. This is critical to the appropriate management of the fungal risk in hematology, cancer and transplantation patients.

  14. Status of environmental response efforts at radioactively contaminated sites in the united states air force installation restoration program

    International Nuclear Information System (INIS)

    Rowe, W.D. Jr.; McEntee, T.E. Jr.; Johnson, B.; Manning, L.

    1995-01-01

    The United States Air Force has identified approximately 170 radioactively contaminated sites at its domestic installations. These sites contain a variety of low level radioactive and mixed wastes and are classified as burial sites, landfills, buildings, and other disposal sites. Of these 170, approximately 70 are presently being evaluated under the Air Force Installation Restoration Program (IRP) in accordance with applicable laws and regulations. Removal and/or remedial actions have been taken at specific sites using site-specific residual radioactivity criteria. The remaining sites are either under investigation to determine the need for possible action or have been classified as response complete based on restricted or unrestricted future use. This paper describes past Air Force operations that generated radioactive waste materials; examines the current inventory of resulting radioactively contaminated sites in the Air Force IRP; reviews criteria used to evaluate sites for removal and/or remedial actions; provides summary information on actions taken at sites; and focuses on response actions and cleanup levels at two completed sites. The paper concludes with an assessment of outstanding issues relevant to the remediation of radioactively contaminated sites. (author)

  15. Assessment of sediment metal contamination in the Mar Menor coastal lagoon (SE Spain: Metal distribution, toxicity, bioaccumulation and benthic community structure

    Directory of Open Access Journals (Sweden)

    2005-01-01

    Full Text Available The Mar Menor coastal lagoon is one of the largest of the Mediterranean Sea. Ancient mining activities in the mountains near its southern basin have resulted in metal contamination in the sediment. The metal bioavailability of these sediments was determined through laboratory toxicity bioassays using three Mediterranean sea urchin species and two amphipod species, and by means of field bioaccumulation measurements involving the seagrass Cymodocea nodosa. The effect of sediment metal contamination on benthic communities was assessed through benthic infaunal analyses, applying classical descriptive parameters and multivariate techniques. The sediments affected by the mining activities presented high levels of toxicity and metals were also accumulated in the seagrass tissues, pointing to metal bioavailability. Although the classical benthic indices were not clear indicators of disturbance, the multivariate techniques applied provided more consistent conclusions.

  16. Ecotoxicity literature review of selected Hanford Site contaminants

    International Nuclear Information System (INIS)

    Driver, C.J.

    1994-03-01

    Available information on the toxicity, food chain transport, and bioconcentration of several Hanford Site contaminants were reviewed. The contaminants included cesium-137, cobalt-60, europium, nitrate, plutonium, strontium-90, technetium, tritium, uranium, and chromium (III and VI). Toxicity and mobility in both aquatic and terrestrial systems were considered. For aquatic systems, considerable information was available on the chemical and/or radiological toxicity of most of the contaminants in invertebrate animals and fish. Little information was available on aquatic macrophyte response to the contaminants. Terrestrial animals such as waterfowl and amphibians that have high exposure potential in aquatic systems were also largely unrepresented in the toxicity literature. The preponderance of toxicity data for terrestrial biota was for laboratory mammals. Bioconcentration factors and transfer coefficients were obtained for primary producers and consumers in representative aquatic and terrestrial systems; however, little data were available for upper trophic level transfer, particularly for terrestrial predators. Food chain transport and toxicity information for the contaminants were generally lacking for desert or sage brush-steppe organisms, particularly plants and reptiles

  17. Brazing retort manifold design concept may minimize air contamination and enhance uniform gas flow

    Science.gov (United States)

    Ruppe, E. P.

    1966-01-01

    Brazing retort manifold minimizes air contamination, prevents gas entrapment during purging, and provides uniform gas flow into the retort bell. The manifold is easily cleaned and turbulence within the bell is minimized because all manifold construction lies outside the main enclosure.

  18. (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.

  19. Microbiological contamination with moulds in work environment in libraries and archive storage facilities.

    Science.gov (United States)

    Zielinska-Jankiewicz, Katarzyna; Kozajda, Anna; Piotrowska, Malgorzata; Szadkowska-Stanczyk, Irena

    2008-01-01

    Microbiological contamination with fungi, including moulds, can pose a significant health hazard to those working in archives or museums. The species involved include Aspergillus, Penicillium, Geotrichum, Alternaria, Cladosporium, Mucor, Rhizopus, Trichoderma, Fusarium which are associated mostly with allergic response of different types. The aim of the study was to analyse, both in quantitative and qualitative terms, workplace air samples collected in a library and archive storage facilities. Occupational exposure and the related health hazard from microbiological contamination with moulds were assessed in three archive storage buildings and one library. Air samples (total 60) were collected via impact method before work and at hourly intervals during work performance. Surface samples from the artifacts were collected by pressing a counting (RODAC) plate filled with malt extract agar against the surface of the artifacts. The air sample and surface sample analyses yielded 36 different mould species, classified into 19 genera, of which Cladosporium and Penicillium were the most prevalent. Twelve species were regarded as potentially pathogenic for humans: 8 had allergic and 11 toxic properties, the latter including Aspergillus fumigatus. Quantitative analysis revealed air microbiological contamination with moulds at the level ranging from 1.8 x 10(2)-2.3 x 10(3) cfu/m(3). In surface samples from library and archive artifacts, 11 fungal species were distinguished; the number of species per artifact varying from 1-6 and colony count ranging from 4 x 10(1) to 8-10(1) cfu/100 cm(2). Higher contamination levels were found only for Cladosporium cladosporioides (1.48 x 10(3) cfu/100 cm(2)) and Paecillomyces varioti (1.2 x 10(2) cfu/100 cm(2)). At the workposts examined, although no clearly visible signs of mould contamination could be found, the study revealed abundant micromycetes, with the predominant species of Cladosporium and Penicillium. The detected species included

  20. Biodiesel and Cold Temperature Effects on Speciated Mobile Source Air Toxics from Modern Diesel Trucks

    Science.gov (United States)

    Speciated volatile organic compounds (VOCs) with a particular focus on mobile source air toxics (MSATs) were measured in diesel exhaust from three heavy-duty trucks equipped with modern aftertreatment technologies. Emissions testing was conducted on a temperature controlled chass...

  1. Biodiesel and Cold Temperature Effect on Speciated Mobile Source Air Toxics from Modern Diesel Trucks

    Science.gov (United States)

    Speciated volatile organic compounds (VOCs) with a particular focus on mobile source air toxics (MSATs) were measured in diesel exhaust from three heavy-duty trucks equipped with modern aftertreatment technologies. Emissions testing was conducted on a temperature controlled chass...

  2. Effects of H2O, CO2, and N2 Air Contaminants on Critical Airside Strain Rates for Extinction of Hydrogen-Air Counterflow Diffusion Flames

    Science.gov (United States)

    Pellett, G. L.; Wilson, L. G.; Northam, G. B.; Guerra, Rosemary

    1989-01-01

    Coaxial tubular opposed jet burners (OJB) were used to form dish shaped counterflow diffusion flames (CFDF), centered by opposing laminar jets of H2, N2 and both clean and contaminated air (O2/N2 mixtures) in an argon bath at 1 atm. Jet velocities for flame extinction and restoration limits are shown versus wide ranges of contaminant and O2 concentrations in the air jet, and also input H2 concentration. Blowoff, a sudden breaking of CFDF to a stable ring shape, occurs in highly stretched stagnation flows and is generally believed to measure kinetically limited flame reactivity. Restore, a sudden restoration of central flame, is a relatively new phenomenon which exhibits a H2 dependent hysteresis from Blowoff. For 25 percent O2 air mixtures, mole for mole replacement of 25 percent N2 contaminant by steam increased U(air) or flame strength at Blowoff by about 5 percent. This result is consistent with laminar burning velocity results from analogous substitution of steam for N2 in a premixed stoichiometric H2-O2-N2 (or steam) flame, shown by Koroll and Mulpuru to promote a 10 percent increase in experimental and calculated laminar burning velocity, due to enhanced third body efficiency of water in: H + O2 + M yields HO2 + M. When the OJB results were compared with Liu and MacFarlane's experimental laminar burning velocity of premixed stoichiometric H2 + air + steam, a crossover occurred, i.e., steam enhanced OJB flame strength at extinction relative to laminar burning velocity.

  3. Long-Term Effects of Legacy Copper Contamination on Microbial Activity and Soil Physical Properties

    DEFF Research Database (Denmark)

    Arthur, Emmanuel; Møldrup, Per; Holmstrup, Martin

    Soils heavily contaminated with copper (Cu) are considered unsuitable for agricultural use due to adverse impacts on microbial activity, soil physical properties, and direct toxicity to crops. This study investigated effects of Cu pollution from timber preservation activities between 1911 and 1924...... on soil micro-organisms and subsequent effects on physical properties of a sandy loam soil. Tillage operations over the last 70 years have caused spreading of the initially localized contamination and have created a Cu concentration gradient from 20 to 3800 mg kg-1 across an agricultural field in Hygum......, Denmark. Soil samples obtained from the fallow field were used to determine total microbial activity using fluorescein diacetate and dehydrogenase assays. The physical properties measured included water-dispersible clay, bulk density, air permeability and air-filled porosity. Significant differences...

  4. OPERATIONAL LIMITATIONS FOR DEMOLITION OF A HIGHLY ALPHA CONTAMINATED BUILDING MODLES VERSUS MEASURED AIR & SURFACE ACTIVITY CONCENTRATIONS

    Energy Technology Data Exchange (ETDEWEB)

    LLOYD, E.R.

    2006-11-02

    The demolition of a facility historically used for processing and handling transuranic materials is considered. Residual alpha emitting radionuclide contamination poses an exposure hazard if released to the local environment during the demolition. The process of planning for the demolition of this highly alpha contaminated building, 232-Z, included a predemolition modeling analysis of potential exposures. Estimated emission rates were used as input to an air dispersion model to estimate frequencies of occurrence of peak air and surface exposures. Postdemolition modeling was also conducted, based on the actual demolition schedule and conditions. The modeling results indicated that downwind deposition is the main operational limitation for demolition of a highly alpha-contaminated building. During the demolition of 232-Z, airborne radiation and surface contamination were monitored. The resultant non-detect monitoring results indicate a significant level of conservatism in the modeled results. This comparison supports the use of more realistic assumption in the estimating emission rates. The resultant reduction in modeled levels of potential exposures has significant implications in terms of the projected costs of demolition of such structures.

  5. Predicting soil, water, and air concentrations of environmental contaminants locally and regionally: Multimedia transport and transformation models

    International Nuclear Information System (INIS)

    McKone, T.E.; Daniels, J.I.

    1991-10-01

    Environmental scientists recognize that the environment functions as a complex, interconnected system. A realistic risk-management strategy for many contaminants requires a comprehensive and integrated assessment of local and regional transport and transformation processes. In response to this need, we have developed multimedia models that simulate the movement and transformation of chemicals as they spread through air, water, biota, soils, sediments, surface water, and ground water. Each component of the environment is treated as a homogeneous subsystem that can exchange water, nutrients, and chemical contaminants with other adjacent compartments. In this paper, we illustrate the use of multimedia models and measurements as tools for screening the potential risks of contaminants released to air and deposited onto soil and plants. The contaminant list includes the volatile organic compounds (VOCs) tetrachloroethylene (PCE) and trichloroethylene (TCE), the semi-volatile organic compound benzo(a)pyrene, and the radionuclides tritium and uranium-238. We examine how chemical properties effect both the ultimate route and quantity of human and ecosystem contact and identify sensitivities and uncertainties in the model results

  6. [Air contamination in the Autonomous City of Buenos Aires: the current risk or future climate change, a false option].

    Science.gov (United States)

    Abrutzky, Rosana; Dawidowski, Laura; Murgida, Ana; Natenzon, Claudia Eleonor

    2014-09-01

    Based on the theoretical framework of environmental risk, this article discusses the management of air quality in the Autonomous City of Buenos Aires in relation to current and potential impacts of toxic gases and global climate change on the health of the population. Information on historical and current management of the air was linked to the results of the South American Emissions, Megacities and Climate research project to assess danger, exposure, vulnerability and uncertainty as the dimensions of risk. By contextualizing public policies developed in recent decades on this subject, it was possible to identify emerging configurations of risk and uncertainties as accelerators of social vulnerability. On the one hand, the fact that there is a positive correlation between mortality, changes in temperature and air pollution was confirmed. On the other hand, it became clear that there is a disconnect between air quality management and health care management, while limitations were found in the proposed mitigation measures relating to emissions of greenhouse gases produced by fuel, revealing uncertainties regarding their efficacy.

  7. Treatability test of a stacked-tray air stripper for VOC in water

    Energy Technology Data Exchange (ETDEWEB)

    Pico, T., LLNL

    1998-04-01

    A common strategy for hydraulic containment and mass removal at VOC contaminated sites is `pump and treat (P&T)`. In P&T operations, contaminated ground water is pumped from wells, treated above ground, and discharged. Many P&T remediation systems at VOC sites rely on air stripping technology because VOCs are easily transferred to the vapor phase. In stacked-tray air strippers, contaminated water is aerated while it flows down through a series of trays. System operations at LLNL are strictly regulated by the California and federal Environmental Protection Agencies (Cal/EPA and EPA), the Bay Area Air Quality Management District (BAAQMD), the California Regional Water Quality Control Board (RWQCB) and the Department of Toxic Substances Control (DTSC). These agencies set discharge limits, require performance monitoring, and assess penalties for non-compliance. National laboratories are also subject to scrutiny by the public and other government agencies. This extensive oversight makes it necessary to accurately predict field treatment performance at new extraction locations to ensure compliance with all requirements prior to facility activation. This paper presents treatability test results for a stacked- tray air stripper conducted at LLNL and compares them to the vendor`s modeling software results.

  8. Assessment of potentially toxic metal contamination in the soils of a legacy mine site in Central Victoria, Australia.

    Science.gov (United States)

    Abraham, Joji; Dowling, Kim; Florentine, Singarayer

    2018-02-01

    The environmental impact of toxic metal contamination from legacy mining activities, many of which had operated and were closed prior to the enforcement of robust environmental legislation, is of growing concern to modern society. We have carried out analysis of As and potentially toxic metals (Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, and Zn) in the surface soil of a legacy gold mining site in Maldon, Victoria, Australia, to reveal the status of the current metal concentration. The results revealed the median concentrations of metals from highest to lowest, in the order: Mn > Zn > As > Cr > Cu > Pb > Ni > Co > Hg > Cd. The status of site was assessed directly by comparing the metal concentrations in the study area with known Australian and Victorian average top soil levels and the health investigation levels set by the National Environmental Protection Measures (NEPM) and the Department of Environment and Conservation (DEC) of the State of Western Australia. Although, median concentrations of As, Hg, Pb, Cu and Zn exceeded the average Australian and Victorian top soil concentrations, only As and Hg exceeded the ecological investigation levels (EIL) set by DEC and thus these metals are considered as risk to the human and aquatic ecosystems health due to their increase in concentration and toxicity. In an environment of climate fluctuation with increased storm events and forest fires may mobilize these toxic metals contaminants, pose a real threat to the environment and the community. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Identification and treatment of lithium as the primary toxicant in a groundwater treatment facility effluent

    International Nuclear Information System (INIS)

    Kszos, L.A.; Crow, K.R.

    1996-01-01

    6 Li is used in manufacturing nuclear weapons, shielding, and reactor control rods. Li compounds have been used at DOE facilities and Li-contaminated waste has historically been land disposed. Seep water from burial grounds near Y-12 contain small amounts of chlorinated hydrocarbons, traces of PCBs, and 10-19 mg/L Li. Seep treatment consists of oil-water separation, filtration, air stripping, and carbon adsorption. Routine biomonitoring tests using fathead minnows and Ceriodaphniadubia are conducted. Evaluation of suspected contaminants revealed that toxicity was most likely due to Li. Laboratory tests showed that 1 mg Li/L reduced the survival of both species; 0.5 mg Li/L reduced Ceriodaphnia reproduction and minnow growth. However, the toxicity was greatly reduced in presence of sodium (up to 4 mg Li/L, Na can fully negate the toxic effect of Li). Because of the low Na level discharged from the treatment facility, Li removal from the ground water was desired. SuperLig reg-sign columns were used (Li-selective organic macrocycle bonded to silica gel). Bench-scale tests showed that the material was very effective for removing Li from the effluent, reducing the toxicity

  10. Modeling emissions and dispersion of contaminants from cleanup activities at a mixed waste site to estimate air impacts and risks

    International Nuclear Information System (INIS)

    Chang, Y.S.; Menlove, S.

    1993-09-01

    The transport and dispersion of contaminants via the air pathway is a major concern during cleanup of contaminated sites. Impacts to air quality and human health during cleanup were evaluated for the Weldon Spring site by using site-specific information for source areas, activities, and receptor locations. In order to ensure protection of human health and the environment, results are being used to focus on those cleanup activities for which release controls should be emphasized

  11. Up the stack : coal-fired electricity's toxic impact : an OCAA air quality report

    International Nuclear Information System (INIS)

    Rang, S.

    2002-07-01

    Ontario Power Generation (OPG) must report annually its releases and transfers of 268 chemicals to the federal National Pollutant Release Inventory (NPRI). Each OPG facility reports the amount of chemicals released to the air, land, water and injected under ground at the facility site. The facilities must also report the amount of chemicals that are transferred off-site for treatment, sewage, disposal, recycling or energy recovery. In 1999 and 2000, atmospheric releases from OPG's coal-fired plants accounted for a significant percentage of the total pollutants released for Ontario and Canada. OPG's facilities are often in the top 5 in Ontario and Canada for releases of various chemicals, including persistent toxic chemicals. In 1999, the Nanticoke coal-fired power plant on Lake Erie was ranked first in Canada for releases to the air. Data reported for the 1999 and 2000 reporting period for dioxins and furans, hexachlorobenzene, mercury, metals (chromium, nickel and arsenic), and acid gases such as hydrochloric acid, hydrogen fluoride, and sulphuric acid clearly indicates that OPG coal-fired plants are a leading source of air pollution in Canada and Ontario. The Ontario Clean Air Alliance suggests the data is sufficient to phase-out the use of coal for power generation in Ontario. It recommends conserving energy and replacing coal-fired power with renewable energy sources such as wind and water power. Converting coal facilities to high-efficiency natural gas units would also reduce the toxic impacts of OPG's coal-fired power plants. As an immediate first step, it was recommended that the government should ban non-emergency exports of coal-fired electricity during smog-alert periods in Ontario. 11 tabs

  12. Elements of a unified prognostic model for secondary air contamination by resuspension

    International Nuclear Information System (INIS)

    Besnus, F.; Garger, E.; Gordeev, S.; Hollaender, W.; Kashparov, V.; Martinez-Serrano, J.; Mironov, V.; Nicholson, K.; Tschiersch, J.; Vintersved, I.

    1996-01-01

    Based on results of several joint experimental campaigns and an extensive literature survey, a prognostic model was constructed capable of predicting airborne activity concentrations and size distributions as well as soil surface activity concentrations as a function of time and meteorological conditions. Example scenario calculations show that agricultural practices are of lesser importance to secondary air contamination than dust storms immediately after primary deposition and forest fires

  13. Radioactive Mapping Contaminant of Alpha on The Air in Space of Repair of Hot Cell and Medium Radioactivity Laboratory in Radio metallurgy Installation

    International Nuclear Information System (INIS)

    Yusuf-Nampira; Endang-Sukesi; S-Wahyuningsih; R-Budi-Santoso

    2007-01-01

    Hot cell and space of acid laboratory medium activity in Radio metallurgy Installation are used for the examination preparation of fuel nuclear post irradiation. The sample examined is dangerous radioactive material representing which can disseminate passing air stream. The dangerous material spreading can be pursued by arranging air stream from laboratory space to examination space. To know the performance the air stream arrangement is hence conducted by radioactive mapping contaminant of alpha in laboratory / space of activity place, for example, medium activity laboratory and repair space. This mapping radioactivity contaminant is executed with the measurement level of the radioactivity from sample air taken at various height with the distance of 1 m, various distance and from potential source as contaminant spreading access. The mapping result indicate that a little spreading of radioactive material happened from acid cupboard locker to laboratory activity up to distance of 3 m from acid cupboard locker and spreading of radioactive contaminant from goods access door of the hot cell 104 to repair space reach the distance of 2 m from goods door access. Level of the radioactive contamination in the space was far under maximum limitation allowed (20 Bq / m 3 ). (author)

  14. Metal and pharmaceutical mixtures: Is ion loss the mechanism underlying acute toxicity and widespread additive toxicity in zebrafish?

    Energy Technology Data Exchange (ETDEWEB)

    Alsop, Derek, E-mail: alsopde@mcmaster.ca; Wood, Chris M.

    2013-09-15

    Highlights: •Zebrafish larvae were used to test the acute toxicity of contaminant mixtures. •Interactions were observed between metals, ammonia and pharmaceuticals. •Larval Na{sup +} loss was observed with exposure to all acutely toxic contaminants tested. •Water quality criteria should recognize the toxic interactions between contaminants. -- Abstract: The acute toxicities and mechanisms of action of a variety of environmental contaminants were examined using zebrafish larvae (Danio rerio; 4–8 days post fertilization). Toxic interactions were observed between metals. For example, the addition of a sublethal level of nickel (15% of the LC{sub 50}, one third of the LC{sub 01}) to all copper treatments decreased the copper 96 h LC{sub 50} by 58%, while sublethal copper exposure (6% of the copper LC{sub 50}, 13% of the LC{sub 01}) decreased the cadmium 96 h LC{sub 50} by 47%. Two predictive models were assessed, the concentration addition (CA) model, which assumes similar mechanisms of action, and the independent action (IA) model, which assumes different mechanisms of action. Quantitative comparisons indicated the CA model performed better than the IA model; the latter tended to underestimate combined toxicity to a greater extent. The effects of mixtures with nickel or ammonia were typically additive, while mixtures with copper or cadmium were typically greater than additive. Larvae exposed to cadmium, copper or nickel experienced whole body ion loss. Decreases were greatest for Na{sup +} followed by K{sup +} (as high as 19% and 9%, respectively, in 24 h). Additive toxicity between copper and other pharmaceutical compounds such as fluoxetine (Prozac™), β-naphthoflavone, estrogen and 17α-ethinylestradiol were also observed. Similar to metals, acutely toxic concentrations of fluoxetine, β-naphthoflavone and ammonia all decreased whole body Na{sup +} and K{sup +}. Overall, whole body Na{sup +} loss showed the greatest correlation with mortality across a

  15. Metal and pharmaceutical mixtures: Is ion loss the mechanism underlying acute toxicity and widespread additive toxicity in zebrafish?

    International Nuclear Information System (INIS)

    Alsop, Derek; Wood, Chris M.

    2013-01-01

    Highlights: •Zebrafish larvae were used to test the acute toxicity of contaminant mixtures. •Interactions were observed between metals, ammonia and pharmaceuticals. •Larval Na + loss was observed with exposure to all acutely toxic contaminants tested. •Water quality criteria should recognize the toxic interactions between contaminants. -- Abstract: The acute toxicities and mechanisms of action of a variety of environmental contaminants were examined using zebrafish larvae (Danio rerio; 4–8 days post fertilization). Toxic interactions were observed between metals. For example, the addition of a sublethal level of nickel (15% of the LC 50 , one third of the LC 01 ) to all copper treatments decreased the copper 96 h LC 50 by 58%, while sublethal copper exposure (6% of the copper LC 50 , 13% of the LC 01 ) decreased the cadmium 96 h LC 50 by 47%. Two predictive models were assessed, the concentration addition (CA) model, which assumes similar mechanisms of action, and the independent action (IA) model, which assumes different mechanisms of action. Quantitative comparisons indicated the CA model performed better than the IA model; the latter tended to underestimate combined toxicity to a greater extent. The effects of mixtures with nickel or ammonia were typically additive, while mixtures with copper or cadmium were typically greater than additive. Larvae exposed to cadmium, copper or nickel experienced whole body ion loss. Decreases were greatest for Na + followed by K + (as high as 19% and 9%, respectively, in 24 h). Additive toxicity between copper and other pharmaceutical compounds such as fluoxetine (Prozac™), β-naphthoflavone, estrogen and 17α-ethinylestradiol were also observed. Similar to metals, acutely toxic concentrations of fluoxetine, β-naphthoflavone and ammonia all decreased whole body Na + and K + . Overall, whole body Na + loss showed the greatest correlation with mortality across a variety of toxicants. We theorize that a disruption of

  16. Toxicity of sediments potentially contaminated by coal mining and natural gas extraction to unionid mussels and commonly tested benthic invertebrates

    Science.gov (United States)

    Wang, Ning; Ingersoll, Christopher G.; Kunz, James L.; Brumbaugh, William G.; Kane, Cindy M.; Evans, R. Brian; Alexander, Steven; Walker, Craig; Bakaletz, Steve

    2013-01-01

    Sediment toxicity tests were conducted to assess potential effects of contaminants associated with coal mining or natural gas extraction activities in the upper Tennessee River basin and eastern Cumberland River basin in the United States. Test species included two unionid mussels (rainbow mussel, Villosa iris, and wavy-rayed lampmussel, Lampsilis fasciola, 28-d exposures), and the commonly tested amphipod, Hyalella azteca (28-d exposure) and midge, Chironomus dilutus (10-d exposure). Sediments were collected from seven test sites with mussel communities classified as impacted and in proximity to coal mining or gas extraction activities, and from five reference sites with mussel communities classified as not impacted and no or limited coal mining or gas extraction activities. Additional samples were collected from six test sites potentially with high concentrations of polycyclic aromatic hydrocarbons (PAHs) and from a test site contaminated by a coal ash spill. Mean survival, length, or biomass of one or more test species was reduced in 10 of 14 test samples (71%) from impacted areas relative to the response of organisms in the five reference samples. A higher proportion of samples was classified as toxic to mussels (63% for rainbow mussels, 50% for wavy-rayed lampmussels) compared with amphipods (38%) or midge (38%). Concentrations of total recoverable metals and total PAHs in sediments did not exceed effects-based probable effect concentrations (PECs). However, the survival, length, or biomasses of the mussels were reduced significantly with increasing PEC quotients for metals and for total PAHs, or with increasing sum equilibrium-partitioning sediment benchmark toxic units for PAHs. The growth of the rainbow mussel also significantly decreased with increasing concentrations of a major anion (chloride) and major cations (calcium and magnesium) in sediment pore water. Results of the present study indicated that (1) the findings from laboratory tests were generally

  17. [Biological contamination in office buildings related to ventilation/air conditioning system].

    Science.gov (United States)

    Bródka, Karolina; Sowiak, Małgorzata; Kozajda, Anna; Cyprowski, Marcin; Irena, Szadkowska-Stańczyk

    2012-01-01

    Indoor air is contaminated with microorganisms coming from both the atmospheric air and sources present in premises. The aim of this study was to analyze the concentrations of biological agents in office buildings, dependending on ventilation/air conditioning system and season. The study covered office buildings (different in the system of ventila-tion/air conditioning). Air samples for assessing the levels of inhalable dust, endotoxins and (1-->3)-beta-D-glucans, were taken at the selected stationary points of each building during summer and winter. The air was sampled for 6 h, using portable sets consisting of the GilAir 5 pump and the head filled with a filter of fiber glass. The samples for the presence of airborne bacteria and fungi were collected twice during the day using the impaction method. Average concentrations of inhalable dust, bacteria, fungi, endotoxins and (1-->3)-beta-D-glucans in office premises were 0.09 mg/m3, 6.00 x 10(2) cfu/m3, 4.59 x 10(1) cfu/m3, 0.42 ng/m3 and 3.91 ng/m3, respectively. Higher concentrations of the investigated agents were found in summer. In premises with air conditioning concentrations of airborne fungi, (1-->3)-beta-D-glucans and inhalable dust were significantly lower in winter. In summer the trend was reverse except for (1-->3)-beta-D-glucans. Concentrations of biological agents were affected by the season and the presence of air conditioning. Concentrations of inhalable dust, bacteria, fungi, endotoxins and (1-->3)-beta-D-glucans, observed inside the office buildings, were significantly higher in summer than in winter. The presence of the air conditioning system modified in various ways the levels of biological agents. Its influence was greater on the concentration of fungi and (1-->3)-beta-D-glucans than on that of bacteria and endotoxins.

  18. Contamination mechanisms of air basin with tritium in venues of underground nuclear explosions at the former Semipalatinsk test site.

    Science.gov (United States)

    Lyakhova, O N; Lukashenko, S N; Larionova, N V; Tur, Y S

    2012-11-01

    During the period of testing from 1945 to 1962 at the territory of Semipalatinsk test site (STS) within the Degelen Mountains in tunnels, 209 underground nuclear explosions were produced. Many of the tunnels have seasonal water seepage in the form of streams, through which tritium migrates from the underground nuclear explosion (UNE) venues towards the surface. The issue of tritium contamination occupies a special place in the radioactive contamination of the environment. In this paper we assess the level and distribution of tritium in the atmospheric air of ecosystems with water seepage at tunnels № 176 and № 177, located on "Degelen" site. There has been presented general nature of tritium distribution in the atmosphere relative to surface of a watercourse which has been contaminated with tritium. The basic mechanisms were studied for tritium distribution in the air of studied ecosystems, namely, the distribution of tritium in the systems: water-atmosphere, tunnel air-atmosphere, soil water-atmosphere, vegetation-atmosphere. An analytical calculation of tritium concentration in the atmosphere by the concentration of tritium in water has been performed. There has experimentally obtained the dependence for predictive assessment of tritium concentrations in air as a function of tritium concentration in one of the inlet sources such as water, tunnel air, soil water, vegetation, etc.. The paper also describes the general nature of tritium distribution in the air in the area "Degelen". Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Plasma flame for mass purification of contaminated air with chemical and biological warfare agents

    International Nuclear Information System (INIS)

    Uhm, Han S.; Shin, Dong H.; Hong, Yong C.

    2006-01-01

    An elimination of airborne simulated chemical and biological warfare agents was carried out by making use of a plasma flame made of atmospheric plasma and a fuel-burning flame, which can purify the interior air of a large volume in isolated spaces such as buildings, public transportation systems, and military vehicles. The plasma flame generator consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber. For example, a reaction chamber, with the dimensions of a 22 cm diameter and 30 cm length, purifies an airflow rate of 5000 lpm contaminated with toluene (the simulated chemical agent) and soot from a diesel engine (the simulated aerosol for biological agents). Large volumes of purification by the plasma flame will free mankind from the threat of airborne warfare agents. The plasma flame may also effectively purify air that is contaminated with volatile organic compounds, in addition to eliminating soot from diesel engines as an environmental application

  20. Potential risks of metal toxicity in contaminated sediments of Deule river in Northern France

    International Nuclear Information System (INIS)

    Lourino-Cabana, Beatriz; Lesven, Ludovic; Charriau, Adeline; Billon, Gabriel; Ouddane, Baghdad; Boughriet, Abdel

    2011-01-01

    Research highlights: → A historical environmental pollution is evidenced with reference to background levels. → Sedimentary trace metals partitioning is examined under undisturbed conditions. → Anoxia and diagenetic processes induce geochemical and mineralogical variabilities. → Do metals present in particles and pore waters exhibit a potential toxicity risk? → Behaviour of binding fractions contributes to trace metals scavenging. - Abstract: The aim of this paper was to evaluate the potential sediment cumulative damage and toxicity due to metal contamination in a polluted zone of Deule river (in northern France) from nearby two smelters. Metal-enrichment factors and geoaccumulation indices measured with sediment depth revealed that - compared to background levels either in local reference soils or in world rivers sediments/suspended particulate matter - Cd contributed to the highest pollution levels, followed by Zn, Pb and to a much lesser extent Cu and Ni. A comparison of the vertical distribution of AVS (acid volatile sulfides), SEM (simultaneously extracted metals), TMC (total metal concentrations), TOC (total organic carbon) and interstitial water-metal concentrations in the sediment allowed us to highlight the extent of toxicity caused by Cd, Pb, Zn, Ni and Cu and to raise the possibility of their association with certain geochemical phases. To assess the actual environmental impacts of these metals in Deule river, numerical sediment quality guidelines were further used in the present work. Sedimentary Pb, Zn, and Cd contents largely exceeded PEC (probable effect concentration) values reported as consensus-based sediment quality guidelines for freshwater ecosystems. As for risks of toxicity from pore waters, metal concentrations reached their maxima at the surficial layers of the sediment (1-3 cm) and IWCTU (Interstitial Water Criteria Toxicity Unit) observed for Pb and to a lesser extent Cd, violated the corresponding water quality data recommended

  1. In situ treatment of arsenic-contaminated groundwater by air sparging.

    Science.gov (United States)

    Brunsting, Joseph H; McBean, Edward A

    2014-04-01

    Arsenic contamination of groundwater is a major problem in some areas of the world, particularly in West Bengal (India) and Bangladesh where it is caused by reducing conditions in the aquifer. In situ treatment, if it can be proven as operationally feasible, has the potential to capture some advantages over other treatment methods by being fairly simple, not using chemicals, and not necessitating disposal of arsenic-rich wastes. In this study, the potential for in situ treatment by injection of compressed air directly into the aquifer (i.e. air sparging) is assessed. An experimental apparatus was constructed to simulate conditions of arsenic-rich groundwater under anaerobic conditions, and in situ treatment by air sparging was employed. Arsenic (up to 200 μg/L) was removed to a maximum of 79% (at a local point in the apparatus) using a solution with dissolved iron and arsenic only. A static "jar" test revealed arsenic removal by co-precipitation with iron at a molar ratio of approximately 2 (iron/arsenic). This is encouraging since groundwater with relatively high amounts of dissolved iron (as compared to arsenic) therefore has a large theoretical treatment capacity for arsenic. Iron oxidation was significantly retarded at pH values below neutral. In terms of operation, analysis of experimental results shows that periodic air sparging may be feasible. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. 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

  3. Methods for Sampling and Measurement of Compressed Air Contaminants

    International Nuclear Information System (INIS)

    Stroem, L.

    1976-10-01

    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

  4. Pharmaceuticals, hormones, personal-care products, and other organic wastewater contaminants in water resources: Recent research activities of the U.S. Geological Survey's toxic substances hydrology program

    Science.gov (United States)

    Focazio, Michael J.; Kolpin, Dana W.; Buxton, Herbert T.

    2003-01-01

    Recent decades have brought increasing concerns for potential contamination of water resources that could inadvertently result during production, use, and disposal of the numerous chemicals offering improvements in industry, agriculture, medical treatment, and even common household products. Increasing knowledge of the environmental occurrence or toxicological behavior of these contaminants from various studies in Europe, United States, and elsewhere has resulted in increased concern for potential adverse environmental and human health effects (Daughton and Ternes, 1999). Ecologists and public health experts often have incomplete understandings of the toxicological significance of many of these contaminants, particularly long-term, low-level exposure and when they occur in mixtures with other contaminants (Daughton and Ternes, 1999; Kümmerer, 2001). In addition, these ‘emerging contaminants’ are not typically monitored or assessed in ambient water resources. The need to understand the processes controlling the transport and fate of these contaminants in the environment, and the lack of knowledge of the significance of long-term exposures have increased the need to study environmental occurrence down to trace (nanogram per liter) levels. Furthermore, the possibility that mixtures of environmental contaminants may interact synergistically or antagonistically has increased the need to characterize the types of mixtures that are found in our waters. The U.S. Geological Survey’s Toxic Substances Hydrology Program (Toxics Program) is developing information and tools on emerging water-quality issues that will be used to design and improve water-quality monitoring and assessment programs of the USGS and others, and for proactive decision-making by industry, regulators, the research community, and the public (http://toxics.usgs.gov/regional/emc.html). This research on emerging water-quality issues includes a combination of laboratory work to develop new analytical

  5. Measurement of underground contamination of non-aqueous phase liquids (NAPLs) on the basis of the radon concentration in ground level air

    International Nuclear Information System (INIS)

    Schubert, M.

    2001-01-01

    It was investigated whether measurements of radon concentrations in ground level air are a suitable method of detecting sub-surface soil contamination with non-aqueous phase liquids (NAPLs). The working postulation was that, due to the very high solubility of radon in NAPLs, and the resulting accumulation of radon in NAPLs, radon exhalation to the ground level air in the proximity of such NAPL contamination should be locally reduced, thus indicating contamination of sub-surface soils with NAPLs. The research work reported was to verify the working theory by way of experiments, and to finally develop a reliable detection method for NAPL contaminations. The investigations comprised theoretical studies, laboratory experiments, experiments in defined soil columns, and extensive field studies [de

  6. Use of a horizontal air-dispersion system to enhance biodegradation of diesel fuel contaminated soils

    International Nuclear Information System (INIS)

    Baker, J.N.; Nickerson, D.A.; Guest, P.R.; Portele, T.E.

    1993-01-01

    A horizontal air-dispersion system was designed and installed to enhance the natural biodegradation of residual diesel fuel contaminated soils at an underground storage tank (UST) facility in Seattle, Washington. This system was designed to operate in conjunction with an existing free-product recovery system which exposes more heavily contaminated soils at the capillary fringe to injected air. Results of a pilot study conducted at the facility indicate that an initial biodegradation rate of 2,200 mg of total petroleum hydrocarbons (TPH) per kg of soil per year will be achieved, making in-situ biodegradation a feasible remedial alternative for contaminated site soils. Oxygen, carbon dioxide, and hydrocarbon vapor concentrations have been monitored since full-scale startup in September 1992, using a series of vapor monitoring points (VMPs) installed in the vicinity of the aerated beds and around the perimeter of the facility. Recent monitoring data indicate that the system is capable of aerating soils at distances greater than 80 feet from the aerated beds. Oxygen utilization and carbon dioxide production measured during post-startup respiration tests indicate microbial activity has increased as a result of seven months of full-scale system operation

  7. Modeled occupational exposures to gas-phase medical laser-generated air contaminants.

    Science.gov (United States)

    Lippert, Julia F; Lacey, Steven E; Jones, Rachael M

    2014-01-01

    Exposure monitoring data indicate the potential for substantive exposure to laser-generated air contaminants (LGAC); however the diversity of medical lasers and their applications limit generalization from direct workplace monitoring. Emission rates of seven previously reported gas-phase constituents of medical laser-generated air contaminants (LGAC) were determined experimentally and used in a semi-empirical two-zone model to estimate a range of plausible occupational exposures to health care staff. Single-source emission rates were generated in an emission chamber as a one-compartment mass balance model at steady-state. Clinical facility parameters such as room size and ventilation rate were based on standard ventilation and environmental conditions required for a laser surgical facility in compliance with regulatory agencies. All input variables in the model including point source emission rates were varied over an appropriate distribution in a Monte Carlo simulation to generate a range of time-weighted average (TWA) concentrations in the near and far field zones of the room in a conservative approach inclusive of all contributing factors to inform future predictive models. The concentrations were assessed for risk and the highest values were shown to be at least three orders of magnitude lower than the relevant occupational exposure limits (OELs). Estimated values do not appear to present a significant exposure hazard within the conditions of our emission rate estimates.

  8. Toxicity of Single and Mixed Contaminants in Seawater Measured with Acute Toxicity Bioassays

    Directory of Open Access Journals (Sweden)

    A.R. Fernandez-Alba

    2002-01-01

    Full Text Available Different types of organic pollutants commonly detected in seawater have been evaluated by acute toxicity bioassays. Vibrio fischeri, Daphnia magna, and Selenastrum capricornotum were selected to test toxic effects of individual compounds and mixtures of these compounds, obtaining EC50 values in the range of 0.001 to 28.9 mg/l. In the case of mixtures, synergistic toxic responses were seen for a clear majority of the cases (>60%. Mixtures containing methyl-tertiary-butyl ether (MTBE exhibit accelerated processes that result in a change in concentration required to produce a toxic effect; for example, in the case of mixtures containing MTBE and Diuron and Dichlofluanid.

  9. 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.

    Science.gov (United States)

    O'Connor, T M; Barry, P J; Jahangir, A; Finn, C; Buckley, B M; El-Gammal, A

    2011-01-01

    Arterial blood gases (ABGs) are often sampled incorrectly, leading to a 'mixed' or venous sample. Delays in analysis and air contamination are common. We measured the effects of these errors in patients with chronic obstructive pulmonary disease (COPD) exacerbations and controls. 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. Mean venous pH was 7.371 and arterial pH was 7.407 (p Air contamination was associated with a clinically significant increase in PO₂ in all samples, including those that were immediately analyzed. 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 PO₂, indicating that air-contaminated ABGs should be discarded. Copyright © 2010 S. Karger AG, Basel.

  10. A preliminary survey of marine contamination from mining-related activities on Marinduque Island, Philippines: porewater toxicity and chemistry results from a field trip, October 14-19, 2000

    Science.gov (United States)

    Carr, R. Scott; Nipper, Marion; Plumlee, Geoffrey S.

    2001-01-01

    As a follow-up of an initial overview of environmental problems caused by mining activities on Marinduque Island, Philippines, USGS and TAMU-CC scientists went to Marinduque in October 2000 to do a preliminary assessment of potential impacts of mining-related activities on the marine environment. Like the previous visit in May 2000, the marine assessment was conducted at the invitation of Philippine Congressman Edmund O. Reyes. In this report we present the results of sediment porewater toxicity tests and chemical analyses. Toxicity tests consist of laboratory analyses for the assessment of adverse effects caused by environmental contaminants to animals or plants. Sediments (sand or mud) are known to accumulate contaminants (e.g., copper and other heavy metals). Therefore, it is common to perform toxicity tests using different phases of the sedimentary environment in order to analyze adverse effects of contaminants accumulated in the sediment. Sediment pore water (or interstitial water, i.e., the water distributed among the sediment grains) is a sedimentary phase which controls the bioavailability of contaminants to bottom dwelling aquatic organisms (both plants and animals). There are several different kinds of organisms with which toxicity tests can be performed. Among those, tests with sea urchin early life stages (gametes and embryos) are very common due to their high sensitivity to contaminants, ease of maintenance under laboratory conditions, and ecological importance, particularly in coral reefs. The basis of these tests is the exposure of gametes or embryos to the pore water to be analyzed for toxicity. If the pore water contains contaminants in levels that can adversely affect a number of marine species, fertilization and/or embryological development of sea urchins is inhibited. Chemical analyses provide additional information and aid in the interpretation of the toxicity test results. For the current study, chemical analyses were performed for the

  11. Dietary toxicity of field-contaminated invertebrates to marine fish: effects of metal doses and subcellular metal distribution.

    Science.gov (United States)

    Dang, Fei; Rainbow, Philip S; Wang, Wen-Xiong

    2012-09-15

    There is growing awareness of the toxicological effects of metal-contaminated invertebrate diets on the health of fish populations in metal-contaminated habitats, yet the mechanisms underlying metal bioaccumulation and toxicity are complex. In the present study, marine fish Terapon jurbua terepon were fed a commercial diet supplemented with specimens of the polychaete Nereis diversicolor or the clam Scrobicularia plana, collected from four metal-impacted estuaries (Tavy, Restronguet Creek, West Looe, Gannel) in southwest England, as environmentally realistic metal sources. A comparative toxicological evaluation of both invertebrates showed that fish fed S. plana for 21 d exhibited evident mortality compared to those fed N. diversicolor. Furthermore, a spatial effect on mortality was observed. Differences in metal doses rather than subcellular metal distributions between N. diversicolor and S. plana appeared to be the cause of such different mortalities. Partial least squares regression was used to evaluate the statistical relationship between multiple-metal doses and fish mortality, revealing that Pb, Fe, Cd and Zn in field-collected invertebrates co-varied most strongly with the observed mortality. This study provides a step toward exploring the underlying mechanism of dietary toxicity and identifying the potential causality in complex metal mixture exposures in the field. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Predicting soil, water and air concentrations of environmental contaminants locally and regionally; multimedia transport and transformation models

    International Nuclear Information System (INIS)

    McKone, T.E.; Daniels, J.I.

    1991-01-01

    Environmental scientists recognize that the environment functions as a complex, interconnected system. A realistic risk-management strategy for many contaminants requires a comprehensive and integrated assessment of local and regional transport and transformation processes. In response to this need, we have developed multimedia models that simulate the movement and transformation of chemicals as they spread through air, water, biota, soils, sediments, surface water and ground water. Each component of the environment is treated as a homogeneous subsystem that can exchange water, nutrients, and chemical contaminants with other adjacent compartments. In this paper, we illustrate the use of multimedia models and measurements as tools for screening the potential risks of contaminants released to air and deposited onto soil and plants. The contaminant list includes the volatile organic compounds (VOCs) tetrachloroethylene (PCE) and trichloroethylene (TCE), the semi-volatile organic compound benzo(a)pyrene, and the radionuclides tritium and uranium-238. We examine how chemical properties effect both the ultimate route and quantity of human and ecosystem contact and identify sensitivities and uncertainties in the model results. We consider the advantages of multimedia models relative to environmental monitoring data. (au)

  13. Data Assimilation in Air Contaminant Dispersion Using a Particle Filter and Expectation-Maximization Algorithm

    Directory of Open Access Journals (Sweden)

    Rongxiao Wang

    2017-09-01

    Full Text Available The accurate prediction of air contaminant dispersion is essential to air quality monitoring and the emergency management of contaminant gas leakage incidents in chemical industry parks. Conventional atmospheric dispersion models can seldom give accurate predictions due to inaccurate input parameters. In order to improve the prediction accuracy of dispersion models, two data assimilation methods (i.e., the typical particle filter & the combination of a particle filter and expectation-maximization algorithm are proposed to assimilate the virtual Unmanned Aerial Vehicle (UAV observations with measurement error into the atmospheric dispersion model. Two emission cases with different dimensions of state parameters are considered. To test the performances of the proposed methods, two numerical experiments corresponding to the two emission cases are designed and implemented. The results show that the particle filter can effectively estimate the model parameters and improve the accuracy of model predictions when the dimension of state parameters is relatively low. In contrast, when the dimension of state parameters becomes higher, the method of particle filter combining the expectation-maximization algorithm performs better in terms of the parameter estimation accuracy. Therefore, the proposed data assimilation methods are able to effectively support air quality monitoring and emergency management in chemical industry parks.

  14. Environmental contaminants of emerging concern in seafood – European database on contaminant levels

    International Nuclear Information System (INIS)

    Vandermeersch, Griet; Lourenço, Helena Maria; Alvarez-Muñoz, Diana; Cunha, Sara; Diogène, Jorge; Cano-Sancho, German; Sloth, Jens J.; Kwadijk, Christiaan; Barcelo, Damia; Allegaert, Wim; Bekaert, Karen; Fernandes, José Oliveira; Marques, Antonio

    2015-01-01

    Marine pollution gives rise to concern not only about the environment itself but also about the impact on food safety and consequently on public health. European authorities and consumers have therefore become increasingly worried about the transfer of contaminants from the marine environment to seafood. So-called “contaminants of emerging concern” are chemical substances for which no maximum levels have been laid down in EU legislation, or substances for which maximum levels have been provided but which require revision. Adequate information on their presence in seafood is often lacking and thus potential risks cannot be excluded. Assessment of food safety issues related to these contaminants has thus become urgent and imperative. A database ( (www.ecsafeseafooddbase.eu)), containing available information on the levels of contaminants of emerging concern in seafood and providing the most recent data to scientists and regulatory authorities, was developed. The present paper reviews a selection of contaminants of emerging concern in seafood including toxic elements, endocrine disruptors, brominated flame retardants, pharmaceuticals and personal care products, polycyclic aromatic hydrocarbons and derivatives, microplastics and marine toxins. Current status on the knowledge of human exposure, toxicity and legislation are briefly presented and the outcome from scientific publications reporting on the levels of these compounds in seafood is presented and discussed. - Highlights: • Development of a European database regarding contaminants of emerging concern. • Current status on knowledge of human exposure, toxicity and legislation. • Review on the occurrence of contaminants of emerging concern in seafood.

  15. Environmental contaminants of emerging concern in seafood – European database on contaminant levels

    Energy Technology Data Exchange (ETDEWEB)

    Vandermeersch, Griet, E-mail: griet.vandermeersch@ilvo.vlaanderen.be [Institute for Agricultural and Fisheries Research (ILVO), Animal Sciences Unit – Fisheries, Ankerstraat 1, 8400 Oostende (Belgium); Lourenço, Helena Maria [Division of Aquaculture and Upgrading (DivAV), Portuguese Institute for the Sea and Atmosphere (IPMA), Lisboa (Portugal); Alvarez-Muñoz, Diana [Catalan Institute for Water Research (ICRA), Girona (Spain); Cunha, Sara [LAQV-REQUIMTE, Laboratory of Bromatology and Hydrology, Faculty of Pharmacy, University of Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313 Porto (Portugal); Diogène, Jorge [Institute of Research and Technology in Food and Agriculture (IRTA), Sant Carles de la Ràpita (Spain); Cano-Sancho, German [Laboratory of Toxicology and Environmental Health, School of Medicine, Rovirai Virgili University (URV), Reus (Spain); Sloth, Jens J. [National Food Institute, Technical University of Denmark (DTU Food), Søborg (Denmark); Kwadijk, Christiaan [Institute for Marine Resources and Ecosystem Studies (IMARES), Wageningen University and Research Center, Ijmuiden (Netherlands); Barcelo, Damia [Catalan Institute for Water Research (ICRA), Girona (Spain); Water and Soil Quality Research Group, Department of Environmental Chemistry, IDAEA-CSIC, Barcelona (Spain); Allegaert, Wim; Bekaert, Karen [Institute for Agricultural and Fisheries Research (ILVO), Animal Sciences Unit – Fisheries, Ankerstraat 1, 8400 Oostende (Belgium); Fernandes, José Oliveira [LAQV-REQUIMTE, Laboratory of Bromatology and Hydrology, Faculty of Pharmacy, University of Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313 Porto (Portugal); Marques, Antonio [Division of Aquaculture and Upgrading (DivAV), Portuguese Institute for the Sea and Atmosphere (IPMA), Lisboa (Portugal); and others

    2015-11-15

    Marine pollution gives rise to concern not only about the environment itself but also about the impact on food safety and consequently on public health. European authorities and consumers have therefore become increasingly worried about the transfer of contaminants from the marine environment to seafood. So-called “contaminants of emerging concern” are chemical substances for which no maximum levels have been laid down in EU legislation, or substances for which maximum levels have been provided but which require revision. Adequate information on their presence in seafood is often lacking and thus potential risks cannot be excluded. Assessment of food safety issues related to these contaminants has thus become urgent and imperative. A database ( (www.ecsafeseafooddbase.eu)), containing available information on the levels of contaminants of emerging concern in seafood and providing the most recent data to scientists and regulatory authorities, was developed. The present paper reviews a selection of contaminants of emerging concern in seafood including toxic elements, endocrine disruptors, brominated flame retardants, pharmaceuticals and personal care products, polycyclic aromatic hydrocarbons and derivatives, microplastics and marine toxins. Current status on the knowledge of human exposure, toxicity and legislation are briefly presented and the outcome from scientific publications reporting on the levels of these compounds in seafood is presented and discussed. - Highlights: • Development of a European database regarding contaminants of emerging concern. • Current status on knowledge of human exposure, toxicity and legislation. • Review on the occurrence of contaminants of emerging concern in seafood.

  16. the role of industry in air pollution

    International Nuclear Information System (INIS)

    Kdeih, Naji

    1998-01-01

    Industry is among the main sources of air pollution in Lebanon. Industrial plants emits dangerous effluents affecting on human health and on population living in industrial zones. Personnel within industries ignore the dangerous effect of substances they use in their work and the toxic effect of gaseous, liquid and solid wastes produced and their impact on health and on environment. A major attention should be paid by Lebanese government to avoid the increasing of atmospheric pollution and must encourage the monitoring of air pollution and its effect on human target organs in the influenced zones. Within industries air is contaminated by gases, vapor, dusts in high rates. Attention has to be focused to the diseases due to breathing diseases, Asbestos, arterial high blood pressure, stress, digestive diseases and other

  17. [Indoor air studies of mould fungus contamination of homes of selected patients with bronchial asthma (with special regard to evaluation problems)].

    Science.gov (United States)

    Senkpiel, K; Kurowski, V; Ohgke, H

    1996-02-01

    Investigations of indoor air of the homes of seven patients with asthma bronchiale who showed up with positive reactions following intracutaneous application of fungal allergens revealed that their places of residence were contaminated by fungal and bacterial spores. The number of colony forming units of mesophilic fungal spores of the indoor air ranged from 100 to 1000 CFU/m3 and this was much higher than the mould flora of the outdoor air determined simultaneously. The major fungi species found by the indoor investigation were: Penicillium sp. > Aspergillus sp. > Cladosporium sp., Mucor sp., Chrysonilia sp., Verticillium sp. > Geotrichum sp., Trichoderma sp. In two cases Thermoactinomyces species could be detected in the indoor air. The main cause of fungal contamination were moist building materials on room walls, insufficient air ventilation, bad maintenance of the circulating air-machines and insufficient room hygiene (e.g. biological garbage in the kitchen).

  18. 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

    . The PCB(tot) levels in the air of the contaminated section were 168-3843 ng m(-3) (mean: 1030 ng m(-3)), while the mean levels in the reference apartments were 6.03 ng m(-3). The sum of the 24 measured PCB congeners in sealants from the contaminated section was 187-221680 mg kg(-1). Principal component......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...... analysis revealed four groups among the sealant samples with different congener compositions, only two of which were clearly similar to known PCB mixtures, while two were not. Significant correlations and intercorrelations were observed between the lower chlorinated congeners in air and sealant, e...

  19. New land disposal restrictions on contaminated soil and debris, and newly identified toxicity characteristic organics

    International Nuclear Information System (INIS)

    Fortune, William B.; Schumann, Jean C.; Fallon, William E.; Badden, Janet W.; Smith, Edward H.

    1992-01-01

    The applicability of the Resource Conservation and Recovery Act (RCRA) Land Disposal Restrictions (LDR) program to radioactive mixed wastes (RMW) has been clarified through U.S. Environmental Protection Agency (EPA) and U.S. Department of Energy (DOE) rulemakings and notices. However, a number of waste management concerns involving RMW and RMW-contaminated soil and debris continue to exist with respect to achieving compliance with LDR provisions and treatment standards. Consequently, DOE has become increasingly proactive in its participation in the LDR rulemaking process and in the identification of LDR compliance issues associated with its RMW inventories. Both data and recommendations from across the DOE complex were collected and transmitted to EPA in response to proposed requirements that would implement LDR for contaminated soil and debris, and certain newly identified toxicity characteristic (TC) organics. Much of this information focused on concerns related to the application of proposed regulatory approaches to RMW streams. Highlights from the information included in these DOE responses are presented. (author)

  20. Application of bioassays with Enchytraeus crypticus and Folsomia candida to evaluate the toxicity of a metal-contaminated soil, before and after remediation

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Veronica; Simon, Mariano [Univ. de Almeria (Spain). Dept. de Edafologia y Quimica Agricola; Dietz-Ortiz, Maria; Gestel, Cornelis A.M. van [VU Univ., Amsterdam (Netherlands). Dept. of Animal Ecology

    2011-10-15

    A contaminated soil was amended to reduce bioavailability of metals (As, Cd, Cu, Pb, and Zn) and to modify its potential environmental impacts. Reproduction toxicity tests using two different soil invertebrates, Enchytraeus crypticus and Folsomia candida, were used to evaluate efficiency of soil amendments to reduce metal availability. This study has been carried out on a very contaminated soil from El Arteal mining district (SE Spain). The amendments used were marble sludge from the cutting and polishing of marble, compost from greenhouse wastes, and synthetic iron oxides. Soils were analyzed for cation exchange capacity, organic carbon and calcium carbonate content, particle size distribution, pH, electrical conductivity, and total metal content. Porewater and 0.01 M CaCl{sub 2}-extractable concentrations were measured in unamended and amended soils. Soil organisms were exposed to all treatments and to untreated soil. The parameters evaluated in both bioassays were survival and reproduction. All treatments decreased the porewater and CaCl{sub 2}-extractable concentrations of Zn, Pb, Cd, and Cu. The amendments increased survival and reproduction of E. crypticus, reducing toxicity. Survival of F. candida was also increased by the treatments; its reproduction did, however, not improve. These differences may be due to other factors that may affect collembolan reproduction. The different sensitivity of each test organism to some soil properties such as pH and electrical conductivity, which can affect reproduction, should be considered before interpreting results from bioassays focussed on toxicity due to pollutants. Reproduction toxicity bioassays with soil invertebrates are a good complement of chemical analysis to properly assess the ecological risk of remediation processes. Organisms with different exposure routes and different sensitivities to soil properties should be used simultaneously to assess the environmental risk of metal-contaminated sites and to evaluate

  1. Study of arsenic accumulation in rice and evaluation of protective effects of Chorchorus olitorius leaves against arsenic contaminated rice induced toxicities in Wistar albino rats.

    Science.gov (United States)

    Hosen, Saeed Mohammed Imran; Das, Dipesh; Kobi, Rupkanowar; Chowdhury, Dil Umme Salma; Alam, Md Jibran; Rudra, Bashudev; Bakar, Muhammad Abu; Islam, Saiful; Rahman, Zillur; Al-Forkan, Mohammad

    2016-10-14

    In the present study, we investigated the arsenic accumulation in different parts of rice irrigated with arsenic contaminated water. Besides, we also evaluated the protective effects of Corchorus olitorius leaves against arsenic contaminated rice induced toxicities in animal model. A pot experiment was conducted with arsenic amended irrigation water (0.0, 25.0, 50.0 and 75.0 mg/L As) to investigate the arsenic accumulation in different parts of rice. In order to evaluate the protective effects of Corchorus olitorius leaves, twenty Wistar albino rats were divided into four different groups. The control group (Group-I) was supplied with normal laboratory pellets while groups II, III, and IV received normal laboratory pellets supplemented with arsenic contaminated rice, C. olitorius leaf powder (4 %), arsenic contaminated rice plus C. olitorius leaf powder (4 %) respectively. Different haematological parameters and serum indices were analyzed to evaluate the protective effects of Corchorus olitorius leaves against arsenic intoxication. To gather more supportive evidences of Corchorus olitorius potentiality against arsenic intoxication, histopathological analysis of liver, kidney, spleen and heart tissues was also performed. From the pot experiment, we have found a significant (p ≤ 0.05) increase of arsenic accumulation in different parts of rice with the increase of arsenic concentrations in irrigation water and the trend of accumulation was found as root > straw > husk > grain. Another part of the experiment revealed that supplementation of C. olitorius leaves with arsenic contaminated rice significantly (p rice induced toxicities. Arsenic accumulation in different parts of rice increased dose-dependently. Hence, for irrigation purpose arsenic contaminated water cannot be used. Furthermore, arsenic contaminated rice induced several toxicities in animal model, most of which could be minimized with the food supplementation of Corchorus olitorius

  2. Toxicity Assessment of Contaminated Soils of Solid Domestic Waste Landfill

    Science.gov (United States)

    Pasko, O. A.; Mochalova, T. N.

    2014-08-01

    The paper delivers the analysis of an 18-year dynamic pattern of land pollutants concentration in the soils of a solid domestic waste landfill. It also presents the composition of the contaminated soils from different areas of the waste landfill during its operating period. The authors calculate the concentrations of the following pollutants: chrome, nickel, tin, vanadium, lead, cuprum, zinc, cobalt, beryllium, barium, yttrium, cadmium, arsenic, germanium, nitrate ions and petrochemicals and determine a consistent pattern of their spatial distribution within the waste landfill area as well as the dynamic pattern of their concentration. Test-objects are used in experiments to make an integral assessment of the polluted soil's impact on living organisms. It was discovered that the soil samples of an animal burial site are characterized by acute toxicity while the area of open waste dumping is the most dangerous in terms of a number of pollutants. This contradiction can be attributed to the synergetic effect of the polluted soil, which accounts for the regularities described by other researchers.

  3. Contaminative Influence of Beef Due to the Inhalation of Air and the Ingestion of Soil of Livestock from an Acute Release of Radioactive Materials

    International Nuclear Information System (INIS)

    Hwang, Won Tae; Kim, Eun Han; Suh, Kyung Suk; Jeong, Hyo Jeon; Han, Moon Hee

    2004-01-01

    The contaminative influence of beef due to the inhalation of air and the ingestion of soil of livestock, both of which are dealt with as minor contaminative pathways in most radioecological models but may not be neglected, was comprehensively investigated with the improvement of the Korean food chain model DYNACON. As the results, it was found that both pathways can not be neglected at all in the contamination of beef in the case of an accidental release during the non-grazing period of livestock. The ingestion of soil was more influential in the contamination of beef than the inhalation of air over most time following an release. If precipitation is encountered during an accidental release, contaminative influence due to the ingestion of soil was far greater compared with the cases of no precipitation. This fact was more distinct for a long-lived radionuclide 137 Cs than a short-lived radionuclide '1 31 I (elemental iodine). Compared with the results for milk performed prior to this study, the contaminative pathways due to the inhalation of air and the ingestion of soil were more important in beef because of longer biological half-lives. On the other hand, in the case of an accidental release during the grazing period of livestock, radioactive contamination due to the ingestion of pasture was dominant irrespective of the existence of precipitation during an accidental release. It means that contaminative influence due to the inhalation of air and the ingestion of soil is negligible, like the cases of milk.

  4. Contaminative influence of beef due to the inhalation of air and the ingestion of soil of cattle in an accidental release of radioactive materials

    International Nuclear Information System (INIS)

    Hwang, W. T.; Kim, E. H.; Seo, K. S.; Jung, H. J.; Lee, S. M.; Hang, M. H.

    2004-01-01

    The contaminative influence of beef due to the inhalation of air and the ingestion of soil of cattle, both of which are dealt with as minor contaminative pathways in most radioecological models but may not be neglected, was comprehensively investigated with the improvement of the Korean dynamic food chain model DYNACON. As the results, it was found that both pathways can not be neglected at all in the contamination of beef in the case of an accidental release during the non-grazing period of cattle. The ingestion of soil was more influential in the contamination of beef than the inhalation of air over most time following an release. If precipitation is encountered during an accidental release, contaminative influence due to the ingestion of soil was far greater compared with the cases of no precipitation. This fact was more distinct for a long-lived radionuclide 137 Cs than a short-lived radionuclide 131 I (elemental iodine). Compared with the results for milk performed prior to this study, the contaminative pathways due to the inhalation of air and the ingestion of soil were more important in beef because of longer biological half-lives. In the meantime, in the case of an accidental release during the grazing period of cattle, radioactive contamination due to the ingestion of pasture was dominant irrespective of the existence of precipitation during an accidental release. It means that contaminative influence due to the inhalation of air and the ingestion of soil is negligible like the cases of milk

  5. Contamination vs. Exposure

    Science.gov (United States)

    ... into the environment can cause air, water, surfaces, soil, plants, buildings, people, or animals to become contaminated. ... water to remove contamination. This process is called decontamination. Try to avoid spreading contamination to parts of ...

  6. Multiple inorganic toxic substances contaminating the groundwater of Myingyan Township, Myanmar: arsenic, manganese, fluoride, iron, and uranium.

    Science.gov (United States)

    Bacquart, Thomas; Frisbie, Seth; Mitchell, Erika; Grigg, Laurie; Cole, Christopher; Small, Colleen; Sarkar, Bibudhendra

    2015-06-01

    In South Asia, the technological and societal shift from drinking surface water to groundwater has resulted in a great reduction of acute diseases due to water borne pathogens. However, arsenic and other naturally occurring inorganic toxic substances present in groundwater in the region have been linked to a variety of chronic diseases, including cancers, heart disease, and neurological problems. Due to the highly specific symptoms of chronic arsenic poisoning, arsenic was the first inorganic toxic substance to be noticed at unsafe levels in the groundwater of West Bengal, India and Bangladesh. Subsequently, other inorganic toxic substances, including manganese, uranium, and fluoride have been found at unsafe levels in groundwater in South Asia. While numerous drinking water wells throughout Myanmar have been tested for arsenic, relatively little is known about the concentrations of other inorganic toxic substances in Myanmar groundwater. In this study, we analyzed samples from 18 drinking water wells (12 in Myingyan City and 6 in nearby Tha Pyay Thar Village) and 2 locations in the Ayeyarwaddy River for arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. Concentrations of arsenic, manganese, fluoride, iron, or uranium exceeded health-based reference values in most wells. In addition, any given well usually contained more than one toxic substance at unsafe concentrations. While water testing and well sharing could reduce health risks, none of the wells sampled provide water that is entirely safe with respect to inorganic toxic substances. It is imperative that users of these wells, and users of other wells that have not been tested for multiple inorganic toxic substances throughout the region, be informed of the need for drinking water testing and the health consequences of drinking water contaminated with inorganic toxic

  7. Plant-associated bacterial degradation of toxic organic compounds in soil.

    LENUS (Irish Health Repository)

    McGuinness, Martina

    2009-08-01

    A number of toxic synthetic organic compounds can contaminate environmental soil through either local (e.g., industrial) or diffuse (e.g., agricultural) contamination. Increased levels of these toxic organic compounds in the environment have been associated with human health risks including cancer. Plant-associated bacteria, such as endophytic bacteria (non-pathogenic bacteria that occur naturally in plants) and rhizospheric bacteria (bacteria that live on and near the roots of plants), have been shown to contribute to biodegradation of toxic organic compounds in contaminated soil and could have potential for improving phytoremediation. Endophytic and rhizospheric bacterial degradation of toxic organic compounds (either naturally occurring or genetically enhanced) in contaminated soil in the environment could have positive implications for human health worldwide and is the subject of this review.

  8. Contamination in fractured-rock aquifers: Research at the former Naval Air Warfare Center, West Trenton, New Jersey

    Science.gov (United States)

    Goode, Daniel J.; Tiedeman, Claire; Lacombe, Pierre J.; Imbrigiotta, Thomas E.; Shapiro, Allen M.; Chapelle, Francis H.

    2007-01-01

    The U.S. Geological Survey and cooperators are studying chlorinated solvents in a fractured sedimentary rock aquifer underlying the former Naval Air Warfare Center (NAWC), West Trenton, New Jersey. Fractured-rock aquifers are common in many parts of the United States and are highly susceptible to contamination, particularly at industrial sites. Compared to 'unconsolidated' aquifers, there can be much more uncertainty about the direction and rate of contaminant migration and about the processes and factors that control chemical and microbial transformations of contaminants. Research at the NAWC is improving understanding of the transport and fate of chlorinated solvents in fractured-rock aquifers and will compare the effectiveness of different strategies for contaminant remediation.

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

    Science.gov (United States)

    Luksamijarulkul, Pipat; Aiempradit, Natkitta; Vatanasomboon, Pisit

    2014-09-01

    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. 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 pcontamination 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, pcontamination 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. 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.

  10. Lead: Aspects of its ecology and environmental toxicity. [physiological effects of lead compound contamination of environment

    Science.gov (United States)

    Siegel, S. M.

    1973-01-01

    An analysis of lead toxicity in the Hawaiian environment was conducted. It was determined that lead enters the environment as an industrial contaminant resulting from the combustion of leaded gasoline. The amount of lead absorbed by the plants in various parts of the Hawaiian Islands is reported. The disposition of lead in the sediments of canals and yacht basins was investigated. The methods for conducting the surveys of lead content are described. Possible consequences of continued environmental pollution by burning leaded gasoline are discussed.

  11. Advanced combustor design concept to control NOx and air toxics

    Energy Technology Data Exchange (ETDEWEB)

    Eddings, E.G.; Pershing, D.W.; Molina, A.; Sarofim, A.F.; Spinti, J.P.; Veranth, J.

    1999-03-29

    Direct coal combustion needs to be a primary energy source for the electric utility industry and for heavy manufacturing during the next several decades because of the availability and economic advantage of coal relative to other fuels and because of the time required to produce major market penetration in the energy field. However, the major obstacle to coal utilization is a set of ever-tightening environmental regulations at both the federal and local level. It is, therefore, critical that fundamental research be conducted to support the development of low-emission, high-efficiency pulverized coal power systems. The objective of this program was to develop fundamental understanding regarding the impact of fuel and combustion changes on NOx formation, carbon burnout and air toxic emissions from pulverized coal (pc) combustion. During pc combustion, nitrogen in the coal can be oxidized to form nitrogen oxides (NO{sub x}). The 1990 Clean Air Act Amendments established much stricter NO{sub x} emissions limits for new and existing coal-fired plants, so there has been renewed interest in the processes by which NO{sub x} forms in pc flames. One of the least understood aspects of NO{sub x} formation from pc combustion is the process by which char-N (nitrogen remaining in the char after devolatilization) forms either NO{sub x} or N{sub 2}, and the development of a fundamental understanding of this process was a major focus of this research. The overall objective of this program was to improve the ability of combustion system designers and boiler manufacturers to build high efficiency, low emission pulverized coal systems by improving the design tools available to the industry. The specific program goals were to: Use laboratory experiments and modeling to develop fundamental understanding for a new submodel for char nitrogen oxidation (a critical piece usually neglected in most NOx models.); Use existing bench scale facilities to investigate alternative schemes to

  12. 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

    International Nuclear Information System (INIS)

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

    2008-01-01

    This study focuses on the main routes of distribution and accumulation of different hexachlorocyclohexane (HCH) isomers (mainly α-, β-, γ- and δ-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 β-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. - Hexachlorocyclohexane isomers are preferentially accumulated in above-ground tissues of plants grown in a heavily contaminated site

  13. 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.

  14. Modelling of contamination of surface atmosphere for deflation of Cesium-137 on contaminated territories

    International Nuclear Information System (INIS)

    Bogdanov, A.P.; Zhmura, G.M.

    1994-01-01

    Presence of Cesium 137 in near land air is caused at the contaminated territories by 'local' dusting and transport of the dust from the zone of strong contamination. For large distance is it caused by resuspension of radioactive dust from the surface in the given region. In accordance with the models of dusting round square sources based on Gauss statistical model of dissemination of admixtures in the atmosphere, the contaminated areas of european part of the former of USSR with the density of contamination over 1 Ci/km 2 with Cesium 137 were represented by 30 round square sources covering the main spots of contamination. The results of calculation of contamination of the atmosphere for several cities of Belarus, Russia and Ukraine, where there are the permanent points of observation for the content of radionuclides in the air, have shown that the proposed model of dusting sources describes the contamination of near land air with Cesium 137 reasonably well. 7 refs., 3 tabs

  15. Resuspended contaminated sediments cause sublethal stress to oysters: A biomarker differentiates total suspended solids and contaminant effects.

    Science.gov (United States)

    Edge, Katelyn J; Dafforn, Katherine A; Simpson, Stuart L; Ringwood, Amy H; Johnston, Emma L

    2015-06-01

    Resuspended contaminated sediments represent an important route of contaminant exposure for aquatic organisms. During resuspension events, filter-feeding organisms are exposed to contaminants, in both the dissolved form (at the gills) and the particulate form (in the digestive system). In addition, these organisms must manage the physical stress associated with an increase in total suspended solids (TSS). To date, few studies have experimentally compared the contributions to biological stress of contaminated and clean suspended solids. The authors mixed field-collected sediments (cellular biomarkers (lysosomal membrane stability, lipid peroxidation, and glutathione) were measured to evaluate sublethal toxicity. Lysosomal membrane stability was the most sensitive biomarker for distinguishing effects from resuspended contaminated sediments, as increasing amounts of contaminated TSS increased lysosomal membrane destabilization. The authors' results illustrate the importance of considering contaminant exposures from resuspended sediments when assessing the toxicity of contaminants to aquatic organisms. © 2015 SETAC.

  16. 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...... and result in an increased battery capacity. However, CO2 contamination on the Li2O2 surface confirms an asymmetric increase in the overpotentials; particularly the charging overvoltage exhibits sustantial increase, which would reduce the efficiency of the Li-air battery.......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...

  17. Microbiological evaluation on toxicity amelioration of soil samples contaminated with petroleum-based products

    International Nuclear Information System (INIS)

    Khairuddin Abdul Rahim; Pauline Liew Woan Ying; Ahmad Nazrul Abd Wahid; Shamsiah Abdul Rahman; Mohd Suhaimi Hamzah; Abdul Khalik Wood; Muhamat Omar

    2004-01-01

    Samples of soil materials from oil sludge landfarm in Melaka and petroleum sludge ready for disposal were analysed on their potentially toxic elements and compounds and their microbial population. These were compared against uncontaminated soil samples from agricultural plots and fresh crude petroleum samples obtained from an oil refinery in Kerteh, Terengganu. Enumeration and isolation of culturable microbial populations in the above samples were conducted using standard plate counts and screening methods. Populations of microorganisms from uncontaminated soils were tested on its potential to degrade petroleum derived products on contaminated soil samples and crude petroleum samples in a laboratory experiment. Microorganisms with great potential to degrade petroleum sludge will be further screened in further bioremediation studies in the field. (Author)

  18. Comparison of Air Impaction and Electrostatic Dust Collector Sampling Methods to Assess Airborne Fungal Contamination in Public Buildings.

    Science.gov (United States)

    Normand, Anne-Cécile; Ranque, Stéphane; Cassagne, Carole; Gaudart, Jean; Sallah, Kankoé; Charpin, Denis-André; Piarroux, Renaud

    2016-03-01

    Many ailments can be linked to exposure to indoor airborne fungus. However, obtaining a precise measurement of airborne fungal levels is complicated partly due to indoor air fluctuations and non-standardized techniques. Electrostatic dust collector (EDC) sampling devices have been used to measure a wide range of airborne analytes, including endotoxins, allergens, β-glucans, and microbial DNA in various indoor environments. In contrast, viable mold contamination has only been assessed in highly contaminated environments such as farms and archive buildings. This study aimed to assess the use of EDCs, compared with repeated air-impactor measurements, to assess airborne viable fungal flora in moderately contaminated indoor environments. Indoor airborne fungal flora was cultured from EDCs and daily air-impaction samples collected in an office building and a daycare center. The quantitative fungal measurements obtained using a single EDC significantly correlated with the cumulative measurement of nine daily air impactions. Both methods enabled the assessment of fungal exposure, although a few differences were observed between the detected fungal species and the relative quantity of each species. EDCs were also used over a 32-month period to monitor indoor airborne fungal flora in a hospital office building, which enabled us to assess the impact of outdoor events (e.g. ground excavations) on the fungal flora levels on the indoor environment. In conclusion, EDC-based measurements provided a relatively accurate profile of the viable airborne flora present during a sampling period. In particular, EDCs provided a more representative assessment of fungal levels compared with single air-impactor sampling. The EDC technique is also simpler than performing repetitive air-impaction measures over the course of several consecutive days. EDC is a versatile tool for collecting airborne samples and was efficient for measuring mold levels in indoor environments. © The Author 2015

  19. Air Toxics Emissions from Open Burning of Crop Residues in Southeast Asia

    Science.gov (United States)

    KIM Oanh, N. T.; Permadi, D. A.; Hopke, P. K.; Smith, K. R.; Nguyet, D. A.

    2016-12-01

    Agricultural crops production in Southeast Asia (SEA) increases annually to meet domestic consumption of growing population and also for export. Crop residue open burning (CROB) is commonly practiced by farmers to quickly dispose of huge amounts of the agricultural waste, such as rice straw, generated after each crop cycle. This CROB activity emits various toxic air pollutants as well as short-lived climate pollutants such as black carbon particles. Our study focused on quantifying the 2015 annual emissions of semi-volatile organic compounds including polycyclic aromatic hydrocarbons (PAHs), dioxins/furans (PCDD/PCDF), organochlorine pesticides (OCP), along with other conventional trace gases, particulate matter, and greenhouse gases from CROB in 10 major agricultural crop producing SEA countries. Crop production statistics and current field OB practices were gathered from our primary surveys and relevant secondary data sources. Emission factors for rice straw and maize residue burning were taken mainly from our measurements in Thailand while for other crops relevant published data were used. The best emission estimates of air toxics from CROB in SEA were 112 g-TEQ/yr of PCDD/PCDF, 33 t/yr of OCP, and 25 Gg/yr of total PAH of which the well-known carcinogenic benzo[a]pyrene was 0.3 Gg/yr. The CROB of rice production had the highest shares of emissions (33-95%) among considered 8 crop types. Indonesia was the top contributor to the total SEA emissions (30-45%) followed by Vietnam (16-26%), Thailand (6-22%) and Myanmar (5-18%). The spatial distributions of emissions, 0.1º x 0.1º, for each specie were prepared using MODIS land cover data. Temporally, higher emissions were observed in the harvesting months of the main rice crops. This emissions database can be used in regional air quality modeling studies to assess the impacts of CROB activity and to promote non-open burning alternatives.

  20. [The balance of harmful trace contaminants between the air humidity condensate and air in a simulator of the Mir orbit station moisture condensation unit].

    Science.gov (United States)

    Zlotopol'skiĭ, V M; Smolenskaia, T S

    2000-01-01

    Subject of the investigation was the balance of harmful trace contaminants (HTC) between the air moisture condensate and air in a simulator of the MIR moisture condensation unit. Experiments involved various classes of water-solvent compounds including alcohols (C1-C4), ketons (C1-C2), aldehydes (C1-C2), fatty acids (C2-C4), esters (acetates C4-C6), and ammonium. For most of the compounds, removal efficiency correlates with air humidity and virtually does not depend on the HTC concentration within the range of 0.25 to 59.1 mg/m3.

  1. Measurements of the spatial distribution of tritium in air above a chronically contaminated surface

    International Nuclear Information System (INIS)

    Workman, W.J.G.; Davis, P.A.; Wood, M.J.; Barry, P.J.

    1993-01-01

    Tritium in air (HTO) concentrations were measured over a 13 month period above a surface that is chronically contaminated by tritium-bearing groundwater from a waste management area. The measurements were made using passive diffusion samplers, which were sited at six locations (about 100 m apart) at 0.15, 0.9, and 1.8 m above ground level. The diffusion samplers were compact, sampled at a known rate, and required no external power source. They are ideal for remote locations and require a minimum of effort to collect and analyze the data. HTO-in-air concentration peaked in the summer at 500-1500 Bq.m -3 and decreased in the winter to 1-120 Bq.m -3 . In general, concentration decreased with height above ground level, implying that HTO is being lost from the surface to the atmosphere. The flux of tritium to the atmosphere must, therefore, be taken into account to estimate the tritium mass balance for a contaminated area. (Author) 3 figs., 5 tabs., 10 refs

  2. Atmospheric transport of contaminants to remote arctic wilderness areas: A pilot study

    International Nuclear Information System (INIS)

    Crayton, W.M.; Talbot, S.

    1993-01-01

    The Alaska Maritime National Wildlife Refuge includes the Tuxedni Wilderness Area (WA), which is required to meet the Class 1 air quality requirements of the Clean Air Act (42 CFT 7401 et seq.). The Act specifically protects such areas from significant deterioration; however, most Class 1 Wilderness monitoring focuses on visual impairment and traditional atmospheric pollutants such as NOx. This study was designed to assess the feasibility of also measuring atmospheric transport of potentially toxic elemental and organic contaminants to remote areas as a pilot for subsequent monitoring of Service lands to be undertaken through the Biomonitoring of Environmental Status and Trends (BEST) Program. Located on the western shore of Cook Inlet, the Tuxedni WA lies about 80 km downwind of a major petroleum complex that the City of Anchorage. Elemental contaminants emanating from the city will be studied in two species of widely distributed alpine vegetation (Cladina rangiferina, a lichen; and Hylocomium splendens, a moss) collected from elevated windward slopes on Chisik Island, a remote site in the WA. Vegetation samples will be analyzed for a suite of potentially toxic elements by inductively coupled plasma emission spectrometry and atomic absorption spectrophotometry. Polycyclic aromatic compounds originating from petroleum-related and urban sources will be studied through the deployment of lipid-containing passive accumulators and analysis by gas chromatography with photoionization detection. Reference areas will also be selected and monitored

  3. Contamination mechanisms of air basin with tritium in venues of underground nuclear explosions at the former Semipalatinsk test site

    International Nuclear Information System (INIS)

    Lyakhova, O.N.; Lukashenko, S.N.; Larionova, N.V.; Tur, Y.S.

    2012-01-01

    During the period of testing from 1945 to 1962 at the territory of Semipalatinsk test site (STS) within the Degelen Mountains in tunnels, 209 underground nuclear explosions were produced. Many of the tunnels have seasonal water seepage in the form of streams, through which tritium migrates from the underground nuclear explosion (UNE) venues towards the surface. The issue of tritium contamination occupies a special place in the radioactive contamination of the environment. In this paper we assess the level and distribution of tritium in the atmospheric air of ecosystems with water seepage at tunnels № 176 and № 177, located on “Degelen” site. There has been presented general nature of tritium distribution in the atmosphere relative to surface of a watercourse which has been contaminated with tritium. The basic mechanisms were studied for tritium distribution in the air of studied ecosystems, namely, the distribution of tritium in the systems: water–atmosphere, tunnel air–atmosphere, soil water–atmosphere, vegetation–atmosphere. An analytical calculation of tritium concentration in the atmosphere by the concentration of tritium in water has been performed. There has experimentally obtained the dependence for predictive assessment of tritium concentrations in air as a function of tritium concentration in one of the inlet sources such as water, tunnel air, soil water, vegetation, etc.. The paper also describes the general nature of tritium distribution in the air in the area “Degelen”. - Highlights: ► The basic mechanisms for tritium distribution in the air of nuclear testing sites were examined. ► We researched the distribution of tritium in the systems such as water–atmosphere, tunnel air–atmosphere, soil water–atmosphere and vegetation–atmosphere. ► An analytical calculation of tritium concentration in the atmosphere was performed. ► We experimentally obtained the dependence for predictive assessment of tritium concentrations in

  4. Three-dimensional modeling, estimation, and fault diagnosis of spacecraft air contaminants.

    Science.gov (United States)

    Narayan, A P; Ramirez, W F

    1998-01-01

    A description is given of the design and implementation of a method to track the presence of air contaminants aboard a spacecraft using an accurate physical model and of a procedure that would raise alarms when certain tolerance levels are exceeded. Because our objective is to monitor the contaminants in real time, we make use of a state estimation procedure that filters measurements from a sensor system and arrives at an optimal estimate of the state of the system. The model essentially consists of a convection-diffusion equation in three dimensions, solved implicitly using the principle of operator splitting, and uses a flowfield obtained by the solution of the Navier-Stokes equations for the cabin geometry, assuming steady-state conditions. A novel implicit Kalman filter has been used for fault detection, a procedure that is an efficient way to track the state of the system and that uses the sparse nature of the state transition matrices.

  5. Innovative technologies for removing toxic compounds from groundwater and air

    International Nuclear Information System (INIS)

    Rosocha, L.A.; Allen, G.R.; Anderson, G.K.; Bechtold, L.A.; Coogan, J.J.; Heck, H.G.; Kang, M.; McCulla, W.H.; Secker, D.A.; Smith, J.D.; Tennant, R.A.; Wantuck, P.J.

    1992-01-01

    Innovative waste treatment technologies are being developed to remove hazardous organic wastes from water and air. These technologies involve the generation of highly reactive free radicals and their reaction with organic compounds. Two efficient methods of producing these reactive free radicals are radiolysis and electrical-discharge plasmas. Radiolytic technology involves the irradiation of contaminated media with high-energy electron beams or x rays generated from the beams (megavolt energies, hundreds of kilorad doses). This process is best understood in aqueous solutions, in which sizable quantities of the free radicals e aq - , OH*, and H*, as well as the more stable oxidant H 2 0 2 , are produced. These highly reactive species react with organic contaminants to produce C0 2 , H 2 0, and salts, which are no longer hazardous. Nonequilibrium electrical-discharge plasmas involve the generation of copious quantities of reactive free radicals from the dissociation of molecular oxygen by energetic electrons in the gas-based discharge. One of the most promising technologies for plasma processing is based upon the ''silent electrical discharge'' that has proven to be industrially dependable for the generation of large quantities of ozone

  6. Identifying inequitable exposure to toxic air pollution in racialized and low-income neighbourhoods to support pollution prevention

    Directory of Open Access Journals (Sweden)

    Suzanne Kershaw

    2013-05-01

    Full Text Available Numerous environmental justice studies have confirmed a relationship between population characteristics such as low-income or minority status and the location of environmental health hazards. However, studies of the health risks from exposure to harmful substances often do not consider their toxicological characteristics. We used two different methods, the unit-hazard and the distance-based approach, to evaluate demographic and socio-economic characteristics of the population residing near industrial facilities in the City of Toronto, Canada. In addition to the mass of air emissions obtained from the national pollutant release inventory (NPRI, we also considered their toxicity using toxic equivalency potential (TEP scores. Results from the unit-hazard approach indicate no significant difference in the proportion of low-income individuals living in host versus non-host census tracts (t(107 = 0.3, P = 0.735. However, using the distance-based approach, the proportion of low-income individuals was significantly higher (+5.1%, t(522 = 6.0, P <0.001 in host tracts, while the indicator for “racialized” communities (“visible minority” was 16.1% greater (t(521 = 7.2, P <0.001 within 2 km of a NPRI facility. When the most toxic facilities by non-carcinogenic TEP score were selected, the rate of visible minorities living near the most toxic NPRI facilities was significantly higher (+12.9%, t(352 = 3.5, P = 0.001 than near all other NPRI facilities. TEP scores were also used to identify areas in Toronto that face a double burden of poverty and air toxics exposure in order to prioritise pollution prevention.

  7. Superfund and Toxic Release Inventory Sites - MDC_ContaminatedSite

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A point feature class of open DERM Contaminated sites - see phase code for status of site. Contaminated sites identifies properties where environmental contamination...

  8. Modeling the effects of reformulated gasoline usages on ambient concentrations of ozone and five air toxics

    International Nuclear Information System (INIS)

    Ligocki, M.P.; Schulhof, R.R.; Jackson, R.E.; Jimenez, M.M.; Atkinson, D.

    1993-01-01

    The use of reformulated gasolines to reduce motor-vehicle-related hydrocarbon emissions has been mandated by the 1990 Clean Air Act Amendments for nine severely polluted urban areas. Using a version of the Urban Airshed Model that includes explicit representation of five motor-vehicle-related air toxics, the effects of reformulated gasoline usage on ambient ozone and toxics concentrations were simulated. Simulations were conducted for two urban areas. Baltimore-Washington and Houston, for the year 1995. Additional simulation were conducted for Baltimore-Washington including winter and 1999 scenarios. In the Baltimore-Washington areas, the 1995 Federal reformulated gasoline scenario produce reductions of 1.1 percent in simulated peak ozone and 2.7 percent in the areal extent of simulated ozone exceedances. Simulated ozone reductions were much smaller in Houston. In the reformulated gasoline simulations, secondary formulation of formaldehyde and acetaldehyde was reduced, and decreases in ambient benzene and polycyclic organic matter (POM) concentrations were simulated. Larger reductions in ozone and toxics concentrations were simulated for reformulated gasolines meeting California Phase II standards than for those meeting Federal standards. The effects of reductions in motor-vehicle-related nitrogen oxides (NO x ) emissions, alone and in combination with hydrocarbon reductions, were also examined

  9. Toxicity of fuel-contaminated soil to Antarctic moss and terrestrial algae.

    Science.gov (United States)

    Nydahl, Anna C; King, Catherine K; Wasley, Jane; Jolley, Dianne F; Robinson, Sharon A

    2015-09-01

    Fuel pollution is a significant problem in Antarctica, especially in areas where human activities occur, such as at scientific research stations. Despite this, there is little information on the effects of petroleum hydrocarbons on Antarctic terrestrial biota. The authors demonstrate that the Antarctic mosses Bryum pseudotriquetrum, Schistidium antarctici, and Ceratodon purpureus, and the Antarctic terrestrial alga Prasiola crispa are relatively tolerant to Special Antarctic Blend (SAB) fuel-contaminated soil (measured as total petroleum hydrocarbons). Freshly spiked soils were more toxic to all species than were aged soils containing degraded fuel, as measured by photosynthetic efficiency (variable fluorescence/maximum fluorescence [Fv/Fm]), pigment content, and visual observations. Concentrations that caused 20% inhibition ranged from 16,600 mg/kg to 53,200 mg/kg for freshly spiked soils and from 30,100 mg/kg to 56,200 mg/kg for aged soils. The photosynthetic efficiency of C. purpureus and S. antarctici was significantly inhibited by exposure to freshly spiked soils with lowest-observed-effect concentrations of 27,900 mg/kg and 40,400 mg/kg, respectively. Prasiola crispa was the most sensitive species to freshly spiked soils (Fv/Fm lowest-observed-effect concentration 6700 mg/kg), whereas the Fv/Fm of B. pseudotriquetrum was unaffected by exposure to SAB fuel even at the highest concentration tested (62,900 mg/kg). Standard toxicity test methods developed for nonvascular plants can be used in future risk assessments, and sensitivity data will contribute to the development of remediation targets for petroleum hydrocarbons to guide remediation activities in Antarctica. © 2015 SETAC.

  10. Phytoremediation of Soils Contaminated by Chlorinnated Hydrocarbons

    Science.gov (United States)

    Cho, C.; Sung, K.; Corapcioglu, M.

    2001-12-01

    In recent years, the possible use of deep rooted plants for phytoremediation of soil contaminants has been offered as a potential alternative for waste management, particularly for in situ remediation of large volumes of contaminated soils. Major objectives of this study are to evaluate the effectiveness of a warm season grass (Eastern Gamagrass) and a cool season prairie grass (Annual Ryegrass) in the phytoremediation of the soil contaminated with volatile organic compounds e.g., trichloroethylene (TCE), tetrachloroethylene (PCE), and 1,1,1-trichloroethane (TCA) and to determine the main mechanisms of target contaminant dissipation. The preliminary tests and laboratory scale tests were conducted to identify the main mechanisms for phytoremediation of the target contaminants, and to apply the technique in green house application under field conditions. The results of microcosm and bioreactor experiments showed that volatilization can be the dominant pathway of the target contaminant mass losses in soils. Toxicity tests, conducted in nutrient solution in the growth room, and in the greenhouse, showed that both Eastern gamagrass and Annual ryegrass could grow without harmful effects at up to 400 ppm each of all three contaminants together. Preliminary greenhouse experimentw were conducted with the 1.5 m long and 0.3 m diameter PVC columns. Soil gas concentrations monitored and microbial biomass in bulk and rhizosphere soil, root properties, and contaminant concentration in soil after 100 days were analyzed. The results showed that the soil gas concentration of contaminants has rapidly decreased especially in the upper soil and the contaminant concentraitons in soil were also significantly decreased to 0.024, 0.228, and 0.002 of C/Co for TCE, PCE and TCA, respectively. Significant plant effects were not found however showed contaminant loss through volatilization and plant contamination by air.

  11. Proceedings of the 36. annual aquatic toxicity workshop

    International Nuclear Information System (INIS)

    Martel, L.; Triffault-Bouchet, G.; Fournier, M.; Campbell, P.G.C.; Pellerin, J.; Lacroix, E.; Burridge, L.E.

    2010-01-01

    This workshop was held to discuss topics related to aquatic and environmental toxicology. Principles, issues, and recent innovations in aquatic toxicology were reviewed. New developments in environmental monitoring were discussed, as well as issues related to environmental regulation. The workshop was attended by a range of stakeholders from governments, universities, and industry. The sessions were entitled: legacy contaminants 1 organics; nanotoxicology; environmental effects monitoring; oil sands; BFR and other emerging contaminants; biomarkers; neuro and endocrine disrupting compounds; remediation of degraded aquatic environments; legacy contaminants 2 hydrocarbons; waterborne and diet-borne metals; water and sediment standards and criteria; pesticides; amphibians and wildlife toxicology; cyanobacteria; amphibians and wildlife toxicology 2; environmental risk assessment; genomics, protemics, and metabolomics; contamination in the Saguenay-St. Lawrence Marine park; legacy contaminants 3 organics and metals; community level indicators; toxicity tests; toxicity mechanisms; areas of concern; general aquatic toxicology; general legacy contaminants; emerging contaminants; cyanobacteria; amphibians and wildlife toxicology 1; omics in aquatic ecotoxicology; organism or population level indicators; and toxicity tests. The workshop featured 250 presentations, of which 24 have been catalogued separately for inclusion in this database. tabs., figs.

  12. USE OF POWDERED COCONUT CHARCOAL AS A TOXICITY IDENTIFICATION AND EVALUATION MANIPULATION FOR ORGANIC TOXICANTS IN MARINE SEDIMENTS

    Science.gov (United States)

    We report on a procedure using powdered coconut charcoal to sequester organic contaminants and reduce toxicity in sediments as part of a series of toxicity identification and evaluation (TIE) methods. Powdered coconut charcoal (PCC) was effective in reducing the toxicity of endos...

  13. Problems in assessing the risks of mixtures of contaminants in drinking water

    International Nuclear Information System (INIS)

    Vanderslice, R.R.; Orme, J.; Ohanian, E.V.; Sonich-Mullin, C.

    1989-01-01

    In conducting risk assessments on drinking water contaminants, the U.S. Environmental Protection Agency (EPA) attempts to evaluate all available toxicity data to develop Health Advisory (HA) and Maximum Contaminant Level Goal (MCLG) values. The EPA often has grappled with the issues surrounding the toxicity of chemical mixtures, including radioactive contaminants, nitrate/nitrite, and trihalomethanes (THMs). In evaluating the toxicity of chemical mixtures, the EPA's immediate concern is whether the individual HA values and MCLGs are protecting public health when multiple contaminants are present in drinking water. Potential toxic interactions between drinking water contaminants are difficult to predict because experimental studies are generally performed only at high doses relative to environmental levels. Although the contamination of drinking water involves mixtures of contaminants, drinking water regulations are generally based on an assessment of the risks of individual contaminants. This paper discusses three issues of major concern to the EPA: the synergistic effects of solvent mixtures, vehicle effects in laboratory studies, and setting standards for essential trace nutrients where the absorption and/or toxicity are affected by an individual's nutritional status or other dietary components. 12 references

  14. Chemopreventive effect of natural dietary compounds on xenobiotic-induced toxicity

    Directory of Open Access Journals (Sweden)

    Jia-Ching Wu

    2017-01-01

    Full Text Available Contaminants (or pollutants that affect human health have become an important issue, spawning a myriad of studies on how to prevent harmful contaminant-induced effects. Recently, a variety of biological functions of natural dietary compounds derived from consumed foods and plants have been demonstrated in a number of studies. Natural dietary compounds exhibited several beneficial effects for the prevention of disease and the inhibition of chemically-induced carcinogenesis. Contaminant-induced toxicity and carcinogenesis are mostly attributed to the mutagenic activity of reactive metabolites and the disruption of normal biological functions. Therefore, the metabolic regulation of hazardous chemicals is key to reducing contaminant-induced adverse health effects. Moreover, promoting contaminant excretion from the body through Phase I and II metabolizing enzymes is also a useful strategy for reducing contaminant-induced toxicity. This review focuses on summarizing the natural dietary compounds derived from common dietary foods and plants and their possible mechanisms of action in the prevention/suppression of contaminant-induced toxicity.

  15. Simultaneous biodegradation of volatile and toxic contaminant mixtures by solid–liquid two-phase partitioning bioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Poleo, Eduardo E.; Daugulis, Andrew J., E-mail: andrew.daugulis@chee.queensu.ca

    2013-06-15

    Highlights: • We investigate the simultaneous biodegradation of phenol and butyl acetate. • We identify an effective polymer mixture to selectively absorb each of the substrates and decrease their initial concentration. •The polymer mixture is used to overcome the high phenol cytotoxicity and reduce the abiotic losses of butyl acetate associated with volatility. • The solid–liquid Two Phase Partitioning Bioreactor (TPPB) outperforms the liquid–liquid TPPB and the single phase systems. -- Abstract: Microbial inhibition and stripping of volatile compounds are two common problems encountered in the biotreatment of contaminated wastewaters. Both can be addressed by the addition of a hydrophobic auxiliary phase that can absorb and subsequently re-release the substrates, lowering their initial aqueous concentrations. Such systems have been described as Two Phase Partitioning Bioreactors (TPPBs). In the current work the performances of a solid–liquid TPPB, a liquid–liquid TPPB and a single phase reactor for the simultaneous degradation of butyl acetate (the volatile component) and phenol (the toxic component) have been compared. The auxiliary phase used in the solid–liquid TPPB was a 50:50 polymer mixture of styrene–butadiene rubber and Hytrel{sup ®} 8206, with high affinities for butyl acetate and phenol, respectively. The liquid–liquid TPPB employed silicone oil which has fixed physical properties, and had no capacity to absorb the toxic contaminant (phenol). Butyl acetate degradation was enhanced in both TPPBs relative to the single phase, arising from its sequestration into the auxiliary phase, thereby reducing volatilization losses. The solid–liquid TPPB additionally showed a substantial increase in the phenol degradation rate, relative to the silicone oil system, demonstrating the superiority and versatility of polymer based systems.

  16. The prevalence of toxic hotspots in former Soviet countries.

    Science.gov (United States)

    Sharov, Petr; Dowling, Russell; Gogishvili, Megi; Jones, Barbara; Caravanos, Jack; McCartor, Andrew; Kashdan, Zachary; Fuller, Richard

    2016-04-01

    Using a global database of contaminated sites, toxic hotspots in eight former Soviet countries were analyzed to identify the prevalence, types and sources of toxic pollution, as well as their associated potential public health impacts. For this analysis, polluted sites in Armenia, Azerbaijan, Kazakhstan, Kyrgyzstan, Russia, Tajikistan, Ukraine, and Uzbekistan were compiled and analyzed. The levels of contamination of seven key pollutants were assessed in each country. 424 contaminated sites were identified using data from Blacksmith Institute. Pesticides, lead (Pb), radioactive metals, arsenic (As), mercury (Hg), chromium (Cr), and cadmium (Cd) were the most commonly identified key pollutants. Collectively, these sites pose health risks to an estimated 6.2 million residents. The existing data on toxic hotspots in former Soviet countries likely captures only a small percentage of actual contaminated sites, but suggests potentially severe public health consequences. Additional assessments are needed to understand the risks posed by toxic pollution in the region. Copyright © 2016. Published by Elsevier Ltd.

  17. 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

    people (exhaled air, bioeffluents) and building materials (wall painting). Personalized ventilation combined with chilled ceiling ensured highest air quality at the workstation under all conditions. Pollutant concentration in the occupied zone away from the workstations did not differ substantially...... between the tested systems. Chilled ceiling combined with personalized ventilation working as the only air supplying system may be optimal solution in many buildings.......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...

  18. Actual measurement, hygrothermal response experiment and growth prediction analysis of microbial contamination of central air conditioning system in Dalian, China.

    Science.gov (United States)

    Lv, Yang; Hu, Guangyao; Wang, Chunyang; Yuan, Wenjie; Wei, Shanshan; Gao, Jiaoqi; Wang, Boyuan; Song, Fangchao

    2017-04-03

    The microbial contamination of central air conditioning system is one of the important factors that affect the indoor air quality. Actual measurement and analysis were carried out on microbial contamination in central air conditioning system at a venue in Dalian, China. Illumina miseq method was used and three fungal samples of two units were analysed by high throughput sequencing. Results showed that the predominant fungus in air conditioning unit A and B were Candida spp. and Cladosporium spp., and two fungus were further used in the hygrothermal response experiment. Based on the data of Cladosporium in hygrothermal response experiment, this paper used the logistic equation and the Gompertz equation to fit the growth predictive model of Cladosporium genera in different temperature and relative humidity conditions, and the square root model was fitted based on the two environmental factors. In addition, the models were carried on the analysis to verify the accuracy and feasibility of the established model equation.

  19. Testing of in situ and ex situ bioremediation approaches for an oil-contaminated peat bog following a pipeline break

    International Nuclear Information System (INIS)

    Wilson, J.J.; Lee, D.W.; Yeske, B.M.; Kuipers, F.

    2000-01-01

    The feasibility of treating a 1985 pipeline spill of light Pembina Cardium crude oil at a bog near Violet Grove, Alberta was discussed. Pembina Pipeline Corporation arranged for a treatability test to be conducted on oil-contaminated sphagnum peat moss from the site to determine effective in situ or ex situ remediation options for the site. The test was used to evaluate the biodegradation potential of contaminants. Four tests were designed to simulate field different field treatment approaches and to collect critical data on toxicity and leachability of the peat moss. The tests included a bioslurry test, a soil microcosm test, an aerated water saturated peat column test, and a standard toxicity characteristic leachate potential test. The first three tests gave similar results of at least 74 per cent biodegradation of the residual crude oil on the peat solids and no residual toxicity as measured by the Microtox Assay. It was determined that both in situ bioremediation using an aerated water injection system or an ex situ landfarming approach would achieve required criteria and no fertilizers would be necessary to maintain active bioremediation. The new gas-liquid reactor (GLR) aeration technology used in these tests creates a constant supply of hyperoxygenated water prior to column injection. The continuous release of tiny air bubbles maximizes air surface area and increases the gas transfer rates. 3 tabs., 3 figs

  20. Environmental levels, toxicity and human exposure to tributyltin (TBT)-contaminated marine environment. a review. b_antizar@hotmail.com.

    Science.gov (United States)

    Antizar-Ladislao, Blanca

    2008-02-01

    Tributyltin (TBT) is a toxic chemical used for various industrial purposes such as slime control in paper mills, disinfection of circulating industrial cooling waters, antifouling agents, and the preservation of wood. Due to its widespread use as an antifouling agent in boat paints, TBT is a common contaminant of marine and freshwater ecosystems exceeding acute and chronic toxicity levels. TBT is the most significant pesticide in marine and freshwaters in Europe and consequently its environmental level, fate, toxicity and human exposure are of current concern. Thus, the European Union has decided to specifically include TBT compounds in its list of priority compounds in water in order to control its fate in natural systems, due to their toxic, persistent, bioaccumulative and endocrine disruptive characteristics. Additionally, the International Maritime Organization has called for a global treaty that bans the application of TBT-based paints starting 1 of January 2003, and total prohibition by 1 of January 2008. This paper reviews the state of the science regarding TBT, with special attention paid to the environmental levels, toxicity, and human exposure. TBT compounds have been detected in a number of environmental samples. In humans, organotin compounds have been detected in blood and in the liver. As for other persistent organic pollutants, dietary intake is most probably the main route of exposure to TBT compounds for the general population. However, data concerning TBT levels in foodstuffs are scarce. It is concluded that investigations on experimental toxicity, dietary intake, potential human health effects and development of new sustainable technologies to remove TBT compounds are clearly necessary.

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

    Science.gov (United States)

    Napoli, Christian; Marcotrigiano, Vincenzo; Montagna, Maria Teresa

    2012-08-02

    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. 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). 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. 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.

  2. Glyphosate: environmental contamination, toxicity and potential risks to human health via food contamination.

    Science.gov (United States)

    Bai, Shahla Hosseini; Ogbourne, Steven M

    2016-10-01

    Glyphosate has been the most widely used herbicide during the past three decades. The US Environmental Protection Agency (EPA) classifies glyphosate as 'practically non-toxic and not an irritant' under the acute toxicity classification system. This classification is based primarily on toxicity data and due to its unique mode of action via a biochemical pathway that only exists in a small number of organisms that utilise the shikimic acid pathway to produce amino acids, most of which are green plants. This classification is supported by the majority of scientific literature on the toxic effects of glyphosate. However, in 2005, the Food and Agriculture Organisation (FAO) reported that glyphosate and its major metabolite, aminomethylphosphonic acid (AMPA), are of potential toxicological concern, mainly as a result of accumulation of residues in the food chain. The FAO further states that the dietary risk of glyphosate and AMPA is unlikely if the maximum daily intake of 1 mg kg(-1) body weight (bw) is not exceeded. Research has now established that glyphosate can persist in the environment, and therefore, assessments of the health risks associated with glyphosate are more complicated than suggested by acute toxicity data that relate primarily to accidental high-rate exposure. We have used recent literature to assess the possible risks associated with the presence of glyphosate residues in food and the environment.

  3. "Air Toxics under the Big Sky": Examining the Effectiveness of Authentic Scientific Research on High School Students' Science Skills and Interest

    Science.gov (United States)

    Ward, Tony J.; Delaloye, Naomi; Adams, Earle Raymond; Ware, Desirae; Vanek, Diana; Knuth, Randy; Hester, Carolyn Laurie; Marra, Nancy Noel; Holian, Andrij

    2016-01-01

    "Air Toxics Under the Big Sky" is an environmental science outreach/education program that incorporates the Next Generation Science Standards (NGSS) 8 Practices with the goal of promoting knowledge and understanding of authentic scientific research in high school classrooms through air quality research. This research explored: (1)…

  4. Defences against ammonia toxicity in tropical air-breathing fishes exposed to high concentrations of environmental ammonia: a review.

    Science.gov (United States)

    Ip, Y K; Chew, S F; Wilson, J M; Randall, D J

    2004-10-01

    In the tropics, air-breathing fishes can be exposed to environmental ammonia when stranded in puddles of water during the dry season, during a stay inside a burrow, or after agricultural fertilization. At low concentrations of environmental ammonia, NH(3) excretion is impeded, as in aerial exposure, leading to the accumulation of endogenous ammonia. At high concentrations of environmental ammonia, which results in a reversed NH(3) partial pressure gradient (DeltaP(NH3)), there is retention of endogenous ammonia and uptake of exogenous ammonia. In this review, several tropical air-breathing fishes (giant mudskipper, African catfish, oriental weatherloach, swamp eel, four-eyed sleeper, abehaze and slender African lungfish), which can tolerate high environmental ammonia exposure, are used as examples to demonstrate how eight different adaptations can be involved in defence against ammonia toxicity. Four of these adaptations deal with ammonia toxicity at branchial and/or epithelial surfaces: (1) active excretion of NH(4)(+); (2) lowering of environmental pH; (3) low NH(3) permeability of epithelial surfaces; and (4) volatilization of NH(3), while another four adaptations ameliorate ammonia toxicity at the cellular and subcellular levels: (5) high tolerance of ammonia at the cellular and subcellular levels; (6) reduction in ammonia production; (7) glutamine synthesis; and (8) urea synthesis. The responses of tropical air-breathing fishes to high environmental ammonia are determined apparently by behavioural adaptations and the nature of their natural environments.

  5. Metal and Isotope Analysis of Bird Feathers in a Contaminated Estuary Reveals Bioaccumulation, Biomagnification, and Potential Toxic Effects.

    Science.gov (United States)

    Einoder, L D; MacLeod, C K; Coughanowr, C

    2018-07-01

    The Derwent estuary, in south east Tasmania, is highly contaminated with heavy metals, mainly due to past industrial pollution. This study sought to determine the extent of contamination, bioaccumulation, and biomagnification in the resident bird community and therefore to infer the potential for adverse effects in birds. Thirteen metals were measured from breast feathers (n = 51 individuals) of eight sympatric species of aquatic bird. Stable carbon (δ 13 C) and nitrogen (δ 15 N) isotopes were used to identify dietary sources of contaminants, trophic level, and potential biomagnification through food chains. Generalised linear models revealed that metal burdens were often poorly correlated with δ 13 C, indicating their uptake from a range of freshwater, brackish, and marine carbon sources-not surprising due to widespread contamination across the tidal estuary. Feather mercury increased significantly with trophic level (inferred from δ 15 N). White-bellied Sea-eagle Haliaeetus leucogaster samples contained 240 times more mercury than feral Goose Anser cygnoides. Feather arsenic and copper concentrations were significantly higher in birds feeding lower in the food chain. For several piscivorous species, both chick and adults were sampled revealing significantly higher feather mercury, zinc, and selenium in adults. Feathers from birds found dead along the banks of the estuary had significantly higher lead loads than from live birds, and numerous individuals had levels of mercury, zinc, and lead above toxic thresholds reported in other studies. These results highlight the need to include biota from higher trophic levels in contaminant monitoring programs to understand fully the fate and broader implications of contaminants in the environment.

  6. Inhalation toxicity of indoor air pollutants in Drosophila melanogaster using integrated transcriptomics and computational behavior analyses

    Science.gov (United States)

    Eom, Hyun-Jeong; Liu, Yuedan; Kwak, Gyu-Suk; Heo, Muyoung; Song, Kyung Seuk; Chung, Yun Doo; Chon, Tae-Soo; Choi, Jinhee

    2017-06-01

    We conducted an inhalation toxicity test on the alternative animal model, Drosophila melanogaster, to investigate potential hazards of indoor air pollution. The inhalation toxicity of toluene and formaldehyde was investigated using comprehensive transcriptomics and computational behavior analyses. The ingenuity pathway analysis (IPA) based on microarray data suggests the involvement of pathways related to immune response, stress response, and metabolism in formaldehyde and toluene exposure based on hub molecules. We conducted a toxicity test using mutants of the representative genes in these pathways to explore the toxicological consequences of alterations of these pathways. Furthermore, extensive computational behavior analysis showed that exposure to either toluene or formaldehyde reduced most of the behavioral parameters of both wild-type and mutants. Interestingly, behavioral alteration caused by toluene or formaldehyde exposure was most severe in the p38b mutant, suggesting that the defects in the p38 pathway underlie behavioral alteration. Overall, the results indicate that exposure to toluene and formaldehyde via inhalation causes severe toxicity in Drosophila, by inducing significant alterations in gene expression and behavior, suggesting that Drosophila can be used as a potential alternative model in inhalation toxicity screening.

  7. Microbial fuel cell driving electrokinetic remediation of toxic metal contaminated soils.

    Science.gov (United States)

    Habibul, Nuzahat; Hu, Yi; Sheng, Guo-Ping

    2016-11-15

    An investigation of the feasibility of in-situ electrokinetic remediation for toxic metal contaminated soil driven by microbial fuel cell (MFC) is presented. Results revealed that the weak electricity generated from MFC could power the electrokinetic remediation effectively. The metal removal efficiency and its influence on soil physiological properties were also investigated. With the electricity generated through the oxidation of organics in soils by microorganisms, the metals in the soils would mitigate from the anode to the cathode. The concentrations of Cd and Pb in the soils increased gradually through the anode to the cathode regions after remediation. After about 143days and 108 days' operation, the removal efficiencies of 31.0% and 44.1% for Cd and Pb at the anode region could be achieved, respectively. Soil properties such as pH and soil conductivity were also significantly redistributed from the anode to the cathode regions. The study shows that the MFC driving electrokinetic remediation technology is cost-effective and environmental friendly, with a promising application in soil remediation. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Essential and toxic metals in rice and fishes

    International Nuclear Information System (INIS)

    Chowdhury, M.Z.A.; Monir uddin, M.; Alam, F.; Reaz uddin, M.; Hossain, M.J.; Alam, M.S.

    2003-01-01

    The amount of essential metals such as Na, K, Ca, Mg, Fe, Zn, Cu and Mn in some selected rice and fishes consumed largely by the general people of Chittagong are determined by using the flame photometric and atomic absorption spectrophotometric methods, and are found to be in the range of human necessity. The amounts of some metals such as Pb, Cd, As and Cr in the same samples of rice and fishes are also determined with the help of AAS. The concentration of these toxic metals are actually higher than the tolerance limit of human body. Particularly, the samples produced in the land and hinterland of Chittagong are found to contain considerably higher concentration of lead and chromium than the samples collected from the sea. This indicates that the soil, water and air of land are more contaminated by these metals than the sea-water. The possible sources of lead and chromium are pointed out and the possible ways for remaining away from their contaminations are indicated. The information obtained from these studies are expected to be useful to the general people of this region to select any food for their daily diet on the basis of the abundances of the essential metals or to avoid any food by considering the concentration of the toxic metals. (author)

  9. Contamination and ecological risk assessment of toxic trace elements in the Xi River, an urban river of Shenyang city, China.

    Science.gov (United States)

    Lin, Chunye; He, Mengchang; Liu, Xitao; Guo, Wei; Liu, Shaoqing

    2013-05-01

    The objectives of this study were to assess the enrichment, contamination, and ecological risk posed by toxic trace elements in the sediments of the Xi River in the industrialized city of Shenyang, China. Surface sediment and sediment core were collected; analyzed for toxic trace elements; and assessed with an index of geoaccumulation (Igeo), enrichment factor (EF) value, potential ecological risk factor (Er), ecological risk index (RI), and probable effect concentration quotient (PECQ). Elemental concentrations (milligram per kilogram) were 8.5-637.9 for As, 6.5-103.9 for Cd, 12.2-21.9 for Co, 90.6-516.0 for Cr, 258.1-1,791.5 for Cu, 2.6-19.0 for Hg, 70.5-174.5 for Ni, 126.9-1,405.8 for Pb, 3.7-260.0 for Sb, 38.4-100.4 for V, and 503-4,929 for Zn. The Igeo, EF, Er, and PECQ indices showed that the contamination of Cd and Hg was more serious than that of As, Cr, Cu, Ni, Pb, Sb, and Zn, whereas the presence of Co and V might be primarily from natural sources. The Igeo index for Cr and Ni might underestimate the degree of contamination, potentially as a result of high concentrations of these elements in the shale. The RI index was higher than 600, indicating a notably high ecological risk of sediment for the river. The average PECQ for As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn ranged from 1.4 to 4.1 for surface sediment and from 5.2 to 9.6 in the sediment cores, indicating a high potential for an adverse biological effect. It was concluded that the sediment in the Xi River was severely contaminated and should be remediated as a hazardous material.

  10. Controlled-air incineration of transuranic-contaminated solid waste

    International Nuclear Information System (INIS)

    Borduin, L.C.; Draper, W.E.; Koenig, R.A.; Neuls, A.S.; Warner, C.L.

    1976-01-01

    A controlled-air incinerator and an associated high-energy aqueous off-gas cleaning system are being installed at the Los Alamos Scientific Laboratory (LASL) Transuranic Waste Treatment Development Facility (TDF) for evaluation as a low-level transuranic-contaminated (TRU) solid waste volume reduction process. Program objectives are: (1) assembly and operation of a production scale (45 kg/hr) operation of ''off-the-shelf'' components representative of current incineration and pollution control technology; (2) process development and modification to meet radioactive health and safety standards, and (3) evaluation of the process to define the advantages and limitations of conventional technology. The results of the program will be the design specifications and operating procedures necessary for successful incineration of TRU waste. Testing, with nonradioactive waste, will begin in October 1976. This discussion covers commercially available incinerator and off-gas cleaning components, the modifications required for radioactive service, process components performance expectations, and a description of the LASL experimental program

  11. Modeling for Airborne Contamination

    International Nuclear Information System (INIS)

    F.R. Faillace; Y. Yuan

    2000-01-01

    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 sufficient thickness to simulate the drift

  12. Possible negative consequences of the secondary air contamination on the quality of accumulated drinking water

    International Nuclear Information System (INIS)

    Rihova Ambrozova, J.; Hubackova, J.; Cihakova, I.

    2008-01-01

    At the present time when requirements on quality of drinking water are increased, it is necessary not only to put stress on technological processes used in its preparation, but also there is a need to secure that water is distributed even to the consumer in that quality as it leaves a water station. Through a systematic surveillance of water-supply companies within the framework of biological audits it has been found out that the important points in a distribution network where the quality of water is deteriorated are the water reservoirs. Deterioration in quality of accumulated water is jointly caused by elements of technological, constructional and biological nature. The secondary air contamination has a substantial influence on the creation of bio-films on walls and the presence of microorganisms in accumulated drinking water. To this end, a water twin-compartment reservoir has been systematically evaluated during operation, cleaning meantime and before cleaning. The results of hydro-biological and microbiological analysis have confirmed the input of particles and microorganisms through air, their presence in surface level of accumulated water as well as scrapings from accumulation walls. The surveillance considered also the situation without a fixed filter unit, without door lining etc. On fixing a tested filter system into ventilation duct the risk of air contamination was lowered to minimum. (authors)

  13. Ionisation detectors as monitors of toxic compounds in air

    International Nuclear Information System (INIS)

    Leonhardt, J.W.

    1994-01-01

    Beta particles cause ionisation in gas mixtures. The ions produced provide information on the concentration and identity of trace compounds in ambient air. Modern ionisation detectors use ion mobilities to monitor toxic compounds. Chemical solvent, phosphororganic compounds, PCB and many other toxins can be detected using ion mobility detectors (IMD) in the ppb range or lower. Ion mobility detectors have large potential in industry and research because of their sensitivity, specificity, fast response and relatively low cost. Portable devices and fixed installations are possible. The paper discusses the following topics: (1) ionisation sources in IMD: 63 Ni, 3 H, photoionization and corona discharge, (2) basic principles of ion production, (3) ion collection in IMD, (4) design, gas supply, automatic identification and quantification of IMD data, and (5) selected applications. Advantages and problems with this new type of nuclear analytical instrument are also discussed. (author). 2 refs., 9 figs., 3 tabs

  14. Bioremediation of uranium contaminated soils and wastes

    International Nuclear Information System (INIS)

    Francis, A.J.

    1998-01-01

    Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (1) stabilization of uranium and toxic metals with reduction in waste volume and (2) removal and recovery of uranium and toxic metals from wastes and contaminated soils. Stabilization of uranium and toxic metals in wastes is accomplished by exploiting the unique metabolic capabilities of the anaerobic bacterium, Clostridium sp. The radionuclides and toxic metals are solubilized by the bacteria directly by enzymatic reductive dissolution, or indirectly due to the production of organic acid metabolites. The radionuclides and toxic metals released into solution are immobilized by enzymatic reductive precipitation, biosorption and redistribution with stable mineral phases in the waste. Non-hazardous bulk components of the waste volume. In the second process uranium and toxic metals are removed from wastes or contaminated soils by extracting with the complexing agent citric acid. The citric-acid extract is subjected to biodegradation to recover the toxic metals, followed by photochemical degradation of the uranium citrate complex which is recalcitrant to biodegradation. The toxic metals and uranium are recovered in separate fractions for recycling or for disposal. The use of combined chemical and microbiological treatment process is more efficient than present methods and should result in considerable savings in clean-up and disposal costs

  15. CONTAMINANTS AND REMEDIAL OPTIONS AT PESTICIDE SITES

    Science.gov (United States)

    Many types of soils, sediments, and sludges are contaminated with a wide variety of pesticides. ite-specific characteristics such as volume to be treated, extent of contamination, and applicable cleanup goals differ greatly, and contaminant toxicity, migration pathways, persisten...

  16. Influence of the Pressure Difference and Door Swing on Heavy Contaminants Migration between Rooms.

    Science.gov (United States)

    Hendiger, Jacek; Chludzińska, Marta; Ziętek, Piotr

    2016-01-01

    This paper presents the results of investigations whose aim was to describe the influence of the pressure difference level on the ability of contaminants migration between neighbouring rooms in dynamic conditions associated with door swing. The analysis was based on airflow visualization made with cold smoke, which simulated the heavy contaminants. The test room was pressurized to a specific level and then the door was opened to observe the trail of the smoke plume in the plane of the door. The door was opened in both directions: to the positively and negatively pressurized room. This study focuses on the visualization of smoke plume discharge and an uncertainty analysis is not applicable. Unlike other studies which focus on the analysis of pressure difference, the present study looks at the contaminants which are heavier than air and on "pumping out" the contaminants by means of door swing. Setting the proper level of pressure difference between the contaminated room and the neighbouring rooms can prove instrumental in ensuring protection against toxic contaminants migration. This study helped to establish the threshold of pressure difference necessary to reduce migration of heavy contaminants to neighbouring rooms.

  17. Survey the frequency and type of Fungal Contaminants in Animal Feed of Yazd Dairy Cattles

    Directory of Open Access Journals (Sweden)

    mohammad taghi ghaneian

    2016-04-01

    Full Text Available Introduction About 500,000 species of fungi have been realized up to now. There are abundant fungi in air, soil and our environment. So the growth of them increases in the presence of air moisture and appropriate temperature. However saprophytic fungi have a wide distribution in nature, they are responsible for decomposition of organic materials and playing an important role in the biogeochemical cycles of major nutrients. Some saprophytes are toxic that contaminate human foods and animal feeds by production of mycotoxins. Aflatoxins are the most common and dangerous mycotoxins produced by few species of Aspergillus and penicillium. This group of mycotoxin has disorder and risks, including the induction of liver cancer. They are mutagenic and teratogenic. Aflatoxin B1, B2, G1 and G2, which are naturally produced by several toxic fungi, may contaminate a wide range of dairy animal feeds resulted severe economic loss of cattle meat. Since Aflatoxin B1 and B2 can be transmitted via mammalian’s milk and cheese in form of synthetic Aflatoxin M1 and M2 to human consumers, cause significant health problems. Therefore contamination of animal feed with common toxic airborne saprophytic fungi is a major concern of health officials. Wheat, barley, corn, soybean and other animal feeds may be contaminated with toxic fungi during implantation, harvesting and storage. There are many dairy and livestock centers in Yazd that prepare milk and dairy products for Yazd and neighboring provinces. The aim of current study was to evaluate the amount and type of fungal contaminates of dairy feeds in Yazd dairies. Materials and methods This cross-sectional descriptive study was conducted in the summer of 2012 on 23 dairies in Yazd. Samples of different animal feeds including concentrates, wheat straw, hay, corn, silage corn, soybean and canola as well as waste of bread, were randomly selected from their bulks. The temperature and humidity of feed storage were recorded

  18. Magnesium Contamination in Soil at a Magnesite Mining Area of Jelšava-Lubeník (Slovakia)

    Science.gov (United States)

    Fazekašová, D.; Fazekaš, J.; Hronec, O.; Horňak, M.

    2017-10-01

    Magnesium contamination in soil at a magnesite mining area of Jelšava-Lubeník (Slovakia) and their effect to the soil characteristics were determined. Soil samples were collected in the area Jelšava - Lubeník with specific alkaline pollutants, it is one of the most devastated regions of Slovakia and with the alarming degree of environmental damage. Magnesite air pollutants are a mixture of MgO and MgCO3 due to which a soil reaction can move above pH 8. Production of clink accompanies the enormous emissions of dust particles of MgO into the air and the leakage of gaseous compounds, mainly SO2 and NOx. The total content of heavy metals in soils (Pb, Zn, Cr, Mn, Mg) were determined by atomic absorption spectrometry and X-ray fluorescence spectrometry. Soil reaction was determined in solution of 0.01 M CaCl2. The research showed that the investigated sites are mostly strongly alkaline. Based on the obtained results, it can be stated that the contents of Pb, Zn is below the level of toxicity but for Cr, Mn and Mg, it does not apply. Their significant exceedance points contamination in which we can take into account the harmfulness and toxicity.

  19. 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.

  20. 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

  1. Acute and chronic arsenic toxicity

    OpenAIRE

    Ratnaike, R

    2003-01-01

    Arsenic toxicity is a global health problem affecting many millions of people. Contamination is caused by arsenic from natural geological sources leaching into aquifers, contaminating drinking water and may also occur from mining and other industrial processes. Arsenic is present as a contaminant in many traditional remedies. Arsenic trioxide is now used to treat acute promyelocytic leukaemia. Absorption occurs predominantly from ingestion from the small intestine, though minimal absorption o...

  2. Determining the bioavailability and toxicity of lead contamination to earthworms requires using a combination of physicochemical and biological methods

    International Nuclear Information System (INIS)

    Luo, Wei; Verweij, Rudo A.; Gestel, Cornelis A.M. van

    2014-01-01

    This study aimed at assessing the bioavailability and toxicity of lead to Eisenia andrei in shooting range soils representing different land uses (forest, grassland, bullet plot). Soils contained 47–2398 mg Pb/kg dry weight (dw), but also had different pH-CaCl 2 (3.2–6.8) and organic matter contents (3.8–13%). Therefore artificial soils with different pH and organic matter contents and two natural soils were included as control soils. Earthworms were exposed for 28 days and toxicity and uptake of Pb were related to total, water and 0.01 M CaCl 2 extractable and porewater Pb concentrations as well as to soil characteristics. Pb uptake in the earthworms linearly increased with increasing soil concentrations. At >2000 mg Pb/kg dw and pH 3.3–3.5, high earthworm mortality with significant weight loss and complete inhibition of reproduction were recorded. At <1000 mg/kg dw, earthworm reproduction was more related to differences in pH and other soil characteristics than to Pb. -- Highlights: • Availability and earthworm toxicity of Pb determined in field-contaminated soils. • Earthworm toxicity of most-polluted soils explained from available Pb levels. • Earthworm response in less polluted soils mainly determined by soil pH. • Earthworm toxicity correlated with Pb uptake from the soil. • Soil properties explained differences in earthworm Pb uptake and effects. -- Combination of physicochemical and biological assays helped explaining Pb toxicity in shooting range soils from available Pb concentrations and soil characteristics

  3. Evaluation of decontamination during dismantling of plutonium-contaminated glove boxes

    International Nuclear Information System (INIS)

    Kinugasa, Manabu; Taguchi, Seigi; Ohzeki, Satoru; Inoue, Yoshiaki; Kashima, Sadamitsu

    1981-01-01

    The dismantling work of plutonium-contaminated glove boxes was carried out. These glove boxes had been used for the R and D of plutonium-uranium mixed oxide fuel for 15 years. The work was carried out in a pressure-controlled greenhouse, and the contamination of air in the greenhouse was monitored continuously. In order to reduce the contamination of air during dismantling, the decontamination and fixation of loose contaminants on the surfaces of glove boxes were very important. The correlation between decontamination and the contamination of air regarding dismantling is reported in this paper. The surface contamination density of the glove boxes was measured utilizing the smear method before and after the decontamination, and the decontamination effects were estimated. The contamination of air during dismantling was continuously measured with a plutonium dust monitor. It was found that loose contamination exponentially decreased by the decontamination process. When the so-called wet glove boxes, which contained wet recovery and waste disposal apparatus, were dismantled, the contamination of air did not exceed 500 (MPC) a. However, the contamination of air exceeded 500 (MPC) a several times in the present work of dismantling the so-called dry glove boxes which had been used for the fabrication of plutonium-uranium mixed oxide pellets. (Kato, T.)

  4. Dispersion of Contaminants in Indoor Climate

    DEFF Research Database (Denmark)

    Heiselberg, Per

    In rooms ventilated by mixing ventilation, in order to remove contaminants from the occupied zone, the goal of the air distribution system is to achieve a low and even concentration distribution in the room. The experiments showed that the contaminant distribution in a room always will depend...... on the location of the contamination source and in practice also on the supplied air flow rate and the contaminant density. The results showed that it is important for the removal of contaminants in a room that the ventilation system is working in the same direction as the existing buoyancy forces....

  5. Traffic in the operating room: a review of factors influencing air flow and surgical wound contamination.

    Science.gov (United States)

    Pokrywka, Marian; Byers, Karin

    2013-06-01

    Surgical wound contamination leading to surgical site infection can result from disruption of the intended airflow in the operating room (OR). When personnel enter and exit the OR, or create unnecessary movement and traffic during the procedure, the intended airflow in the vicinity of the open wound becomes disrupted and does not adequately remove airborne contaminants from the sterile field. An increase in the bacterial counts of airborne microorganisms is noted during increased activity levels within the OR. Researchers have studied OR traffic and door openings as a determinant of air contamination. During a surgical procedure the door to the operating room may be open as long as 20 minutes out of each surgical hour during critical procedures involving implants. Interventions into limiting excessive movement and traffic in the OR may lead to reductions in surgical site infections in select populations.

  6. Comparison of personal air samplers and static air samplers

    International Nuclear Information System (INIS)

    Carter, M.W.; Lumsden, B.

    1979-01-01

    The authors demonstrate that radioactive air contamination levels calculated from PAS results will always be higher than air contamination levels calculated from SAS results, other conditions being equal. The most probable explanation seems to be in a relationship between the sampling velocity and the particle size of the dust sampled

  7. Detection of the contamination of air by tritiated water vapour around the reactor EL3

    International Nuclear Information System (INIS)

    Lebouleux, P.; Ardellier, A.; Valero, S.

    1968-01-01

    The authors describe the apparatus used for the detection of the tritiated water vapour contamination in the air around the reactor EL 3. The apparatus consists of two air-circulation ionisation chambers; the air in one of these is dried by passage through a silica-gel column. By carrying out a differential measurement of the ionization currents, it is possible to measure the tritiated water vapour concentration. A theoretical study of the response of the chambers is carried out for two types of emission of the tritiated water vapour: continuous, or in bursts. The experimental work comprises: calibration in the measurement range employed; study of the selectivity for other active gases; study of typical accidents; the interpretation of the results in the case of discontinuous emission, taking into account the desorption from the walls of the measurement chamber, a phenomenon which is observed during the emptying process. The authors give finally actual examples of how to use the results. The apparatus built makes it possible to detect, in less than ten minutes, contamination by tritiated water vapour in the presence of other active gases, in a measurement range of between 3 and 2200 MPC, and with an accuracy of about 25 per cent. A transposition to calculations of the risk to workers should be made with the utmost caution; an envelope of this risk can be drawn up more or less accurately depending on particular cases. (authors) [fr

  8. Arbuscular mycorrhizal fungal inoculation protects Miscanthus × giganteus against trace element toxicity in a highly metal-contaminated site.

    Science.gov (United States)

    Firmin, Stéphane; Labidi, Sonia; Fontaine, Joël; Laruelle, Frédéric; Tisserant, Benoit; Nsanganwimana, Florian; Pourrut, Bertrand; Dalpé, Yolande; Grandmougin, Anne; Douay, Francis; Shirali, Pirouz; Verdin, Anthony; Lounès-Hadj Sahraoui, Anissa

    2015-09-15

    Arbuscular mycorrhizal fungus (AMF)-assisted phytoremediation could constitute an ecological and economic method in polluted soil rehabilitation programs. The aim of this work was to characterize the trace element (TE) phytoremediation potential of mycorrhizal Miscanthus × giganteus. To understand the mechanisms involved in arbuscular mycorrhizal symbiosis tolerance to TE toxicity, the fatty acid compositions and several stress oxidative biomarkers were compared in the roots and leaves of Miscanthus × giganteus cultivated under field conditions in either TE-contaminated or control soils. TEs were accumulated in greater amounts in roots, but the leaves were the organ most affected by TE contamination and were characterized by a strong decrease in fatty acid contents. TE-induced oxidative stress in leaves was confirmed by an increase in the lipid peroxidation biomarker malondialdehyde (MDA). TE contamination decreased the GSSG/GSH ratio in the leaves of exposed plants, while peroxidase (PO) and superoxide dismutase (SOD) activities were increased in leaves and in whole plants, respectively. AMF inoculation also increased root colonization in the presence of TE contamination. The mycorrhizal colonization determined a decrease in SOD activity in the whole plant and PO activities in leaves and induced a significant increase in the fatty acid content in leaves and a decrease in MDA formation in whole plants. These results suggested that mycorrhization is able to confer protection against oxidative stress induced by soil pollution. Our findings suggest that mycorrhizal inoculation could be used as a bioaugmentation technique, facilitating Miscanthus cultivation on highly TE-contaminated soil. Copyright © 2015. Published by Elsevier B.V.

  9. 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. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Construction and applications of DNA probes for detection of polychlorinated biphenyl-degrading genotypes in toxic organic-contaminated soil environments

    International Nuclear Information System (INIS)

    Walia, S.; Khan, A.; Rosenthal, N.

    1990-01-01

    Several DNA probes for polychlorinated biphenyl (PCB)-degrading genotypes were constructed from PCB-degrading bacteria. These laboratory-engineered DNA probes were used for the detection, enumeration, and isolation of specific bacteria degrading PCBs. Dot blot analysis of purified DNA from toxic organic chemical-contaminated soil bacterial communities showed positive DNA-DNA hybridization with a 32P-labeled DNA probe (pAW6194, cbpABCD). Less than 1% of bacterial colonies isolated from garden topsoil and greater than 80% of bacteria isolated from PCB-contaminated soils showed DNA homologies with 32P-labeled DNA probes. Some of the PCB-degrading bacterial isolates detected by the DNA probe method did not show biphenyl clearance. The DNA probe method was found to detect additional organisms with greater genetic potential to degrade PCBs than the biphenyl clearance method did. Results from this study demonstrate the usefulness of DNA probes in detecting specific PCB-degrading bacteria, abundance of PCB-degrading genotypes, and genotypic diversity among PCB-degrading bacteria in toxic chemical-polluted soil environments. We suggest that the DNA probe should be used with caution for accurate assessment of PCB-degradative capacity within soils and further recommend that a combination of DNA probe and biodegradation assay be used to determine the abundance of PCB-degrading bacteria in the soil bacterial community

  11. Plume residence and toxic material accumulation

    International Nuclear Information System (INIS)

    Spigarelli, S.A.; Holpuch, R.

    1975-01-01

    Increased growth rates and 137 Cs concentrations in plume resident trout are thought to be the result of increased metabolism, food consumption, and activity caused by exposure to increased water temperature and flow in thermal discharges. These exposure conditions could contribute to increased accumulation of biologically active, toxic substances by primary forage and predator fish species in the Great Lakes. Uptake and retention of various toxic substances by predators depend on concentrations in forage species (trophic transfer), ambient water, and point source effluents (direct uptake). Contaminants of immediate concern in Great Lakes systems (e.g., chlorinated hydrocarbons) accumulate in adipose tissue, and body concentrations have been correlated with total lipid content in fish. In addition to direct toxic effects on fish, many lipophilic contaminants are known to cause severe human health problems when ingested at concentrations commonly found in Lake Michigan salmonids. Although power plants may or may not be the direct source of a toxic substance, the thermal discharge environment may contribute to the accumulation of toxic substances in fish and the transfer of these materials to man

  12. STUDY ON REMOVAL OF TOXIC METALS FROM WATER USING BIOMATERIALS USING AS AN ADSORBENTS

    OpenAIRE

    R. S. Dubey*, Triptaran Kaur

    2017-01-01

    In today’s date when we talk about purity of things nothing can be placed in the category of being pure. From air to water to soil to food everything is polluted. Pollution can be defined as presence of inappropriate material which may cause harm to living beings. Here we talked about the contaminated water and find out the harmful ingredients present in it. I have studied the presence of toxic metals like copper, cadmium and chromium in our water. Water being the most essential part of once ...

  13. Respiratory tract toxicity in rats exposed to Mexico City air.

    Science.gov (United States)

    Moss, O R; Gross, E A; James, R A; Janszen, D B; Ross, P W; Roberts, K C; Howard, A M; Harkema, J R; Calderón-Garcidueñas, L; Morgan, K T

    2001-03-01

    The rat has been used extensively as a health sentinel, indicator, or monitor of environmental health hazards, but this model has not been directly validated against human exposures. Humans in Mexico City show upper respiratory tract lesions and evidence of pulmonary damage related to their environmental inhalation exposure. In this study, male and female F344 rats were exposed (23 hr/day) in Mexico City to local Mexico City air (MCA)* for up to seven weeks. Controls were maintained at the same location under filtered air. Prior to these exposures, several steps were taken. First, the nasal passages of normal male rats shipped from the United States and housed in Mexico City were examined for mycoplasma infection; no evidence of infection was found. In addition, a mobile exposure and monitoring system was assembled and, with an ozone (O3) exposure atmosphere, was tested along with supporting histopathology techniques and analysis of rat nasal and lung tissues. Last, the entire exposure model (equipment and animals) was transported to Mexico City and validated for a three-week period. During the seven-week study there were 18 one-hour intervals during which the average O3 concentration of MCA in the exposure chamber exceeded the US National Ambient Air Quality Standard (NAAQS) of 0.120 ppm 03 (hourly average, not to be exceeded more than once per year). This prolonged exposure of healthy F344 rats to MCA containing episodically low to moderate concentrations of 03 (as well as other urban air pollutants) did not induce inflammatory or epithelial lesions in the nasal airways or lung as measured by qualitative histologic techniques or quantitative morphometric techniques. These findings agree with those of previous controlled O3 inhalation studies, but they are in contrast to reports indicating that O3-polluted MCA causes significant nasal mucosal injury in adults and children living in southwestern Mexico City. Taken together, these findings may suggest that human

  14. Urban atmospheric contamination

    International Nuclear Information System (INIS)

    Baldasano Jose, M.

    1997-01-01

    The problems of contamination are not only limited to this century, pale pathology evidences of the effects of the contamination of the air exist in interiors in the health of the old ones; the article mention the elements that configure the problem of the atmospheric contamination, atmospheric pollutants and emission sources, orography condition and effects induced by the urbanization process

  15. Development of irradiation technique on controlling food contamination residue

    International Nuclear Information System (INIS)

    Liu Bin; Xiong Shanbai; Xiong Guangquan; Cheng Wei; Chen Yuxia; Liao Tao; Li Xin; Lin Ruotai

    2010-01-01

    The current state of the researches of irradiation technology on controlling food mycotoxin, pesticide, veterinary drugs and fishery drugs residue was summarized. And the degradation rate, mechanism, products and toxicities of food contamination were expatiated. The free radical from irradiation attack the site of weaker bond, and the less or more toxic substances were produced, which lead to the degradation of the food contamination. The limitations and future application of irradiation technique on controlling food contamination were also analyzed. (authors)

  16. Endocrinair : contamination de l'air ambiant : Contamination de l’air ambiant par les perturbateurs endocriniens en Ile de France et caractérisation d’effets toxiques associés

    OpenAIRE

    Chevreuil , Marc; Oziol , Lucie

    2012-01-01

    National audience; En Ile de France, la contamination permanente de l’air ambiant soulève de nouvelles interrogations quant à l’exposition de l’Homme à des perturbateurs endocriniens par cette voie et à la possibilité d’effets sur sa santé, même si ceux-ci sont à faible concentration (micropolluants). Ce qui constitue l’aspect innovant de ce programme, c’est la recherche de molécules semi-volatiles à l’état gazeux ou liées à des particules à l’extérieur et à l’intérieur de locaux (appartement...

  17. Porphyrin pattern and methemoglobin levels in Columba livia applied to assess toxicological risk by air pollution in urban areas.

    Science.gov (United States)

    Sicolo, Matteo; Tringali, Maria; Orsi, Federica; Santagostino, Angela

    2009-11-01

    The study has explored two conservative biomarkers, porphyrin pattern in guano and methemoglobin levels in blood of Columba livia, in order to assay their potential use for monitoring toxic effects induced by exposure to urban air pollution. Fieldwork was conducted between October 2003 and June 2005 in the city of Milan, Italy, by sampling the pigeons in different areas almost twice a week. Six air contaminants, CO, PM10, NO(2), O(3), SO(2), and C(6)H(6), plus polycyclic aromatic hydrocarbons (PAHs) in fine particles, temperature, and UV index, were considered. Protoporphyrins from pigeon excreta sampled outdoors were always higher than in indoor animals, particularly in winter. A positive correlation (p urban air showed significant differences from season to season but only in summer and autumn did the outdoor pigeons show higher values than indoor animals. In summer, a regression model with a positive correlation between O(3) and benzene was determined (p urban air pollution as well as for detecting complex interactions between contaminants in the urban air pollutant mixture was discussed.

  18. Impact of ventilation/pressurization on indoor air contaminants in schools

    International Nuclear Information System (INIS)

    Shaughnessy, R.J.; Levetin, E.; Fisher, E.J.; Ligman, B.K.

    1993-01-01

    As part of a continuing technology development effort to control radon in schools, The U.S. Environmental Protection Agency's (EPA) School Evaluation Program (SEP) team in cooperation with U.S. EPA's Region 6 office has performed radon mitigation in two Southwestern United States schools utilizing the method of ventilation/pressurization control technology. Schools were inspected and IAQ measurements made with respect to carbon dioxide, bioaerosols, volatile organic compounds, and respirable particles. Premitigation results indicated poor ventilation conditions existed throughout the school buildings. Elevated levels of respirable particles were measured, yet no conclusions with respect to health could be implied. Post-mitigation results support, but do not prove the hypothesis that improved ventilation to control radon will also reduce other indicator indoor air contaminants. (orig.). (9 refs., 4 tabs.)

  19. Distribution, exposure pathways, sources and toxicity of nonylphenol ...

    African Journals Online (AJOL)

    Water SA. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue ... of their toxicity, oestrogenic properties and widespread contamination. ... to provide better understanding of these emerging environmental contaminants.

  20. Study of in vitro toxicity and ex vivo and in vivo efficiency of calixarene galenic forms developed for the treatment of cutaneous contamination due to uranium compounds

    International Nuclear Information System (INIS)

    Grives, Sophie

    2015-01-01

    In case of radiological skin contamination by uranium compounds, the only treatments currently available consist in rinsing the contaminated skin area with water and detergent, or with a calcium salt of diethylene triamine pentaacetic acid (Ca-DTPA) solution. However, these procedures are not specific and no efficient treatment for cutaneous contamination due to uranium exists. In the absence of such treatments, uranium diffusion through the skin is fast, inducing an internal exposure after its distribution inside the body through the bloodstream. One part of the bioavailable uranium is up-taken in target organs which are the kidneys and the skeleton, where its toxic effects occur. Therefore a topical formulation consisting of an oil-in-water nano-emulsion incorporating a tricarboxylic calixarene molecule, as a specific chelating agent for uranium, was previously developed. The work achieved in this thesis aimed at evaluating the ex vivo and in vivo decontamination efficiency of this new emergency treatment on intact and superficially wounded skin. For this purpose, skin excoriation model was used. Reproducible models of superficial wounds consisting of micro-cuts and micro-punctures were also developed in order to evaluate the efficiency of the nano-emulsion on physical wounds such as incisions. These studies showed that the calixarene nano-emulsion could be an efficient decontaminating treatment, less aggressive than using the current treatment: soaped water. Its potential cutaneous toxicity was evaluated on in vitro reconstructed human epidermis using three different toxicity tests (MTT, LDH and IL-1-α). These studies demonstrated that the calixarene nano-emulsion did not induce skin toxicity even after 24 h of exposure time. (author)

  1. Monitoring of air toxics through air pathways in support of a No-Migration permit at a refinery land treatment facility

    International Nuclear Information System (INIS)

    Wineberry, W.T. Jr.; McReynolds, J.

    1991-01-01

    As part of Exxon's petition of the EPA for No-Migration variances, ambient concentrations of toxicants and carcinogens are required to be verified through onsite monitoring for comparison to the appropriate health based limits as well as for calibration of previously used atmospheric dispersion models. Ambient air around land treatment facilities us a very complex, dynamic system of interacting chemicals. Pollutants can be found in the gas phase, in the particulate phase, or in the aerosol phase. The complex nature of the dynamic air system around these facilities contributes to the complexity of the sampling and analytical selection for the identification and quantification for these chemicals. The selection of the proper sampling and analysis methods for a pollutant depends on many important interrelated factors, including compounds of interest, the level of detection required, the degree of specificity needed, and the purpose of the data collected. Other factors which may be as important as the above are cost, the accuracy and precision required, need for real-time versus long-term data, and the need for on-site or off-site analysis. Sampling time, sampling rate, the volume of air to be sampled and the acceptable risk level are also factors which must be considered when choosing a sampling method. The purpose of the ambient air monitoring program is to obtain a comparison of predicted concentration to those measured. This paper will focus on the ambient air monitoring program at Exxon's land treatment facility as part of a No-Migration variance to EPA's Land Ban Regulations. Ambient Air Monitoring data involving volatile, semi-volatile and metals/particulate matter less than ten microns (PM-10) will be presented

  2. Leachates draining from controlled municipal solid waste landfill: Detailed geochemical characterization and toxicity tests.

    Science.gov (United States)

    Mavakala, Bienvenu K; Le Faucheur, Séverine; Mulaji, Crispin K; Laffite, Amandine; Devarajan, Naresh; Biey, Emmanuel M; Giuliani, Gregory; Otamonga, Jean-Paul; Kabatusuila, Prosper; Mpiana, Pius T; Poté, John

    2016-09-01

    Management of municipal solid wastes in many countries consists of waste disposal into landfill without treatment or selective collection of solid waste fractions including plastics, paper, glass, metals, electronic waste, and organic fraction leading to the unsolved problem of contamination of numerous ecosystems such as air, soil, surface, and ground water. Knowledge of leachate composition is critical in risk assessment of long-term impact of landfills on human health and the environment as well as for prevention of negative outcomes. The research presented in this paper investigates the seasonal variation of draining leachate composition and resulting toxicity as well as the contamination status of soil/sediment from lagoon basins receiving leachates from landfill in Mpasa, a suburb of Kinshasa in the Democratic Republic of the Congo. Samples were collected during the dry and rainy seasons and analyzed for pH, electrical conductivity, dissolved oxygen, soluble ions, toxic metals, and were then subjected to toxicity tests. Results highlight the significant seasonal difference in leachate physicochemical composition. Affected soil/sediment showed higher values for toxic metals than leachates, indicating the possibility of using lagoon system for the purification of landfill leachates, especially for organic matter and heavy metal sedimentation. However, the ecotoxicity tests demonstrated that leachates are still a significant source of toxicity for terrestrial and benthic organisms. Therefore, landfill leachates should not be discarded into the environment (soil or surface water) without prior treatment. Interest in the use of macrophytes in lagoon system is growing and toxic metal retention in lagoon basin receiving systems needs to be fully investigated in the future. This study presents useful tools for evaluating landfill leachate quality and risk in lagoon systems which can be applied to similar environmental compartments. Copyright © 2016 Elsevier Ltd. All

  3. Effects of low-pressure air on oxygen contamination and lithium corrosion of a tantalum alloy, T-111, at 980 and 1260 C

    Science.gov (United States)

    Gahn, R. F.

    1974-01-01

    The effects were studied of low-pressure air on contamination and corrosion in the tantalum alloy T-111/lithium system at 980 and 1260 C. Capsules of T-111 containing lithium were exposed to six vacuum levels between 1 x 10 to the 8th power and 0.0003 torr by controlled air leakage into a vacuum system. Capsules exposed at 980 C and 0.0002 torr failed from intragranular oxidation. The remainder of the capsules completed the 96-hour tests. The depth of oxygen contamination was greater at 980 C than at 1260 C. Tests made at 0.0001 and 0.00001 torr levels caused large increases in the oxygen content of the T-111. Tests at 0.000001 torr or less produced no significant contamination. No lithium corrosion of the T-111 was observed under any of the conditions.

  4. 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.

  5. 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.

  6. Quantitative risk assessment of drinking water contaminants

    International Nuclear Information System (INIS)

    Cothern, C.R.; Coniglio, W.A.; Marcus, W.L.

    1986-01-01

    The development of criteria and standards for the regulation of drinking water contaminants involves a variety of processes, one of which is risk estimation. This estimation process, called quantitative risk assessment, involves combining data on the occurrence of the contaminant in drinking water and its toxicity. The human exposure to a contaminant can be estimated from occurrence data. Usually the toxicity or number of health effects per concentration level is estimated from animal bioassay studies using the multistage model. For comparison, other models will be used including the Weibull, probit, logit and quadratic ones. Because exposure and toxicity data are generally incomplete, assumptions need to be made and this generally results in a wide range of certainty in the estimates. This range can be as wide as four to six orders of magnitude in the case of the volatile organic compounds in drinking water and a factor of four to five for estimation of risk due to radionuclides in drinking water. As examples of the differences encountered in risk assessment of drinking water contaminants, discussions are presented on benzene, lead, radon and alachlor. The lifetime population risk estimates for these contaminants are, respectively, in the ranges of: <1 - 3000, <1 - 8000, 2000-40,000 and <1 - 80. 11 references, 1 figure, 1 table

  7. System approach for evaluation of air pollution toxic compounds in the 30-km area of nuclear power plants

    International Nuclear Information System (INIS)

    Shevtsova, O.V.; Zhigunova, L.N.; Makovskaya, N.A.; Pavlovich, E.L.

    2012-01-01

    The article shows the importance of a systematic approach to address environmental problems that arise during the construction of nuclear power plants, and identified the need to consider the transformation and biotransformation of primary pollutants and monitoring secondary pollutants. The basic pathways of pollutants in the air a 30-km zone of nuclear power plants established. The content of primary and secondary air pollutants identified. The evaluation of general toxic risk from primary pollutant and the calculation of the carcinogenic risk of secondary pollutants entering the body by inhalation are carried out. (authors)

  8. Bioavailability and mobility of organic contaminants in soil: new three-step ecotoxicological evaluation.

    Science.gov (United States)

    Prokop, Zbyněk; Nečasová, Anežka; Klánová, Jana; Čupr, Pavel

    2016-03-01

    A novel approach was developed for rapid assessment of bioavailability and potential mobility of contaminants in soil. The response of the same test organism to the organic extract, water extract and solid phase of soil was recorded and compared. This approach was designed to give an initial estimate of the total organic toxicity (response to organic extractable fraction), as well as the mobile (response to water extract) and bioavailable fraction (response to solid phase) of soil samples. Eighteen soil samples with different levels of pollution and content of organic carbon were selected to validate the novel three-step ecotoxicological evaluation approach. All samples were chemically analysed for priority contaminants, including aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), hexachlorocyclohexane (HCH) and dichlordiphenyltrichloroethane (DDT). The ecotoxicological evaluation involved determination of toxicity of the organic, mobile and bioavailable fractions of soil to the test organism, bacterium Bacillus cereus. We found a good correlation between the chemical analysis and the toxicity of organic extract. The low toxicity of water extracts indicated low water solubility, and thus, low potential mobility of toxic contaminants present in the soil samples. The toxicity of the bioavailable fraction was significantly greater than the toxicity of water-soluble (mobile) fraction of the contaminants as deduced from comparing untreated samples and water extracts. The bioavailability of the contaminants decreased with increasing concentrations of organic carbon in evaluated soil samples. In conclusion, the three-step ecotoxicological evaluation utilised in this study can give a quick insight into soil contamination in context with bioavailability and mobility of the contaminants present. This information can be useful for hazard identification and risk assessment of soil-associated contaminants. Graphical Abstract New three-step ecotoxicological

  9. Understanding environmental health inequalities through comparative intracategorical analysis: racial/ethnic disparities in cancer risks from air toxics in El Paso County, Texas.

    Science.gov (United States)

    Collins, Timothy W; Grineski, Sara E; Chakraborty, Jayajit; McDonald, Yolanda J

    2011-01-01

    This paper contributes to the environmental justice literature by analyzing contextually relevant and racial/ethnic group-specific variables in relation to air toxics cancer risks in a US-Mexico border metropolis at the census block group-level. Results indicate that Hispanics' ethnic status interacts with class, gender and age status to amplify disproportionate risk. In contrast, results indicate that non-Hispanic whiteness attenuates cancer risk disparities associated with class, gender and age status. Findings suggest that a system of white-Anglo privilege shapes the way in which race/ethnicity articulates with other dimensions of inequality to create unequal cancer risks from air toxics. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Sediment contamination of residential streams in the metropolitan kansas city area, USA: Part II. whole-sediment toxicity to the amphipod hyalella azteca

    Science.gov (United States)

    Tao, J.; Ingersoll, C.G.; Kemble, N.E.; Dias, J.R.; Murowchick, J.B.; Welker, G.; Huggins, D.

    2010-01-01

    This is the second part of a study that evaluates the influence of nonpoint sources on the sediment quality of five adjacent streams within the metropolitan Kansas City area, central United States. Physical, chemical, and toxicity data (Hyalella azteca 28-day whole-sediment toxicity test) for 29 samples collected in 2003 were used for this evaluation, and the potential causes for the toxic effects were explored. The sediments exhibited a low to moderate toxicity, with five samples identified as toxic to H. azteca. Metals did not likely cause the toxicity based on low concentrations of metals in the pore water and elevated concentrations of acid volatile sulfide in the sediments. Although individual polycyclic aromatic hydrocarbons (PAHs) frequently exceeded effect-based sediment quality guidelines [probable effect concentrations (PECs)], only four of the samples had a PEC quotient (PEC-Q) for total PAHs over 1.0 and only one of these four samples was identified as toxic. For the mean PEC-Q for organochlorine compounds (chlordane, dieldrin, sum DDEs), 4 of the 12 samples with a mean PEC-Q above 1.0 were toxic and 4 of the 8 samples with a mean PEC-Q above 3.0 were toxic. Additionally, four of eight samples were toxic, with a mean PEC-Q above 1.0 based on metals, PAHs, polychlorinated biphenyls (PCBs), and organochlorine pesticides. The increase in the incidence of toxicity with the increase in the mean PEC-Q based on organochlorine pesticides or based on metals, PAHs, PCBs, and organochlorine pesticides suggests that organochlorine pesticides might have contributed to the observed toxicity and that the use of a mean PEC-Q, rather than PEC-Qs for individual compounds, might be more informative in predicting toxic effects. Our study shows that stream sediments subject to predominant nonpoint sources contamination can be toxic and that many factors, including analysis of a full suite of PAHs and pesticides of both past and present urban applications and the origins of

  11. Assessment of gold exposure and contamination in galvanizing workplace by neutron activation analysis

    International Nuclear Information System (INIS)

    Menezes, M.A.B.C.; Amaral, A.M.; Maia, E.C.P.; Albinati, C.C.B.

    2007-01-01

    Gold is not included in the current list of elements considered essential to humans and there are many controversies related to its toxicity. According to the chemical characteristics of the element, Au 1+ is favored for binding at sites with S donor, such as sulfhydryl group (-SH) in proteins in biological systems. This tendency raises the possibility of health-related risk, mainly linked to a long-term exposure to high and low levels of gold. This paper highlights the determination of gold by instrumental neutron activation analysis (INAA) during the assessment of exposure levels to metals and possible workers' contamination in three galvanizing factories applying the same processes. This assessment is aimed at giving support to Worker's Health Awareness Program of the Municipal Department of Health of Belo Horizonte, Minas Gerais, Brazil. INAA, mix of k 0 and monostandard methods was applied to air filter, hair and toenail samples, and to urine samples. Solvent extraction of gold was carried out followed by comparative INAA. The results revealed that gold was present in all matrixes, indicating the exposure in the workplace and suggesting endogenous contamination. Is gold playing a role as a toxic element? (author)

  12. Hazardous air pollutant handbook: measurements, properties, and fate in ambient air

    Energy Technology Data Exchange (ETDEWEB)

    Spicer, C.W. (ed.); Gordon, S.M.; Kelly, T.J.; Holdren, M.W.; Mukund, R. [Battelle, Columbus, OH (United States)

    2002-07-01

    Focussing on the 188 hazardous air pollutants (HAPs) identified in the Title III of the US Clean Air Act Amendments, this work reviews the methods used to identify, measure, and locate the presence of toxics in ambient air. After a classification and characterization of the HAPs, the current status of ambient measurement methods are surveyed and categorized according to applicable, likely, and potential methods. The results of studies of ambient air concentrations of the HAPs are presented. Methods used to study atmospheric transformations of toxic air pollutants are reviewed and the concept of atmospheric lifetimes of HAPs is discussed.

  13. Phyto-toxicity and Phyto-remediation Potential of Mercury in Indian Mustard and Two Ferns with Mercury Contaminated Water and Oak Ridge Soil

    International Nuclear Information System (INIS)

    Su, Y.; Han, F.X.; Chen, J.; Shiyab, S.; Monts, D.L.; Monts, D.L.

    2009-01-01

    Phyto-remediation is an emerging technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. Certain fern and Indian mustard species have been suggested as candidates for phyto-remediation of heavy metal-contaminated soil and water because of their high efficiency of accumulating metals in shoots and their high biomass production. Currently, no known hyper-accumulator plants for mercury have been found. Here we report the Hg uptake and phyto-toxicity by two varieties of fern and Indian mustard. Their potential for Hg phyto-remediation application was also investigated. Anatomical, histochemical and biochemical approaches were used to study mercury phyto-toxicity as well as anti-oxidative responses in ferns [Chinese brake fern (P. vittata) and Boston fern (N. exaltata)] and Indian mustard (Florida broadleaf and longstanding) (Brassica juncea L.) grown in a hydroponic system. Phyto-remediation potentials of these plant species were estimated based on their Hg uptake performance with contaminated soils from Oak Ridge (TN, USA). Our results show that mercury exposure led to severe phyto-toxicity accompanied by lipid peroxidation and rapid accumulation of hydrogen peroxide (H 2 O 2 ) in P. vittata, but not in N. exaltata. The two cultivars of fern responded differently to mercury exposure in terms of anti-oxidative enzymes (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD; glutathione reductase, GR). Mercury exposure resulted in the accumulation of ascorbic acid (ASA) and glutathione (GSH) in the shoots of both cultivars of fern. On the other hand, Indian mustard effectively generated an enzymatic antioxidant defense system (especially CAT) to scavenge H 2 O 2 , resulting in lower H 2 O 2 in shoots with higher mercury concentrations. These two cultivars of Indian mustard demonstrated an efficient metabolic defense and adaptation system to mercury-induced oxidative stress. In both varieties of fern and Indian

  14. Bioremediation of contaminated soil

    International Nuclear Information System (INIS)

    Balba, M.T.; Ying, A.C.; McNeice, T.G.

    1992-01-01

    Microorganisms, especially bacteria, yeast and fungi are capable of degrading many kinds of xenobiotic compounds and toxic chemicals such as petroleum hydrocarbon compounds. These microorganisms are ubiquitous in nature and, despite their enormous versatility, there are numerous cases in which long-term contamination of soil and groundwater has been observed. The persistence of the contamination is usually caused by the inability of microorganisms to metabolize these compounds under the prevailing environmental condition. This paper reports on biological remediation of contaminated sites which can be accomplished by using naturally-occurring microorganisms to treat the contaminants. The development of a bioremediation program for a specific contaminated soil system usually includes: A thorough site/soil/waste characterization; Treatability studies

  15. Intermedia transfer factors for fifteen toxic pollutants released to air basins in California

    Energy Technology Data Exchange (ETDEWEB)

    McKone, T.E.; Daniels, J.I. [Lawrence Livermore National Lab., CA (United States); Chiao, F.F.; Hsieh, D.P.H. [Univ. of California, Davis, CA (United States)

    1993-10-01

    This report provides a summary definition of the intermedia-transfer factors (ITFs). Methods are discussed for estimating these parameters in the absence of measured values, and the estimation errors inherent in these estimation methods are considered. A detailed summary is provided of measured and estimated ITF values for fifteen air contaminants. They include: 1,3 butadiene; cadmium; cellosolve; cellosolve acetate; chloroform; di-2-ethylhexylphthalate; 1,4-dioxame; hexachlorobenzene; inorganic arsenic; inorganic lead; nickel; tetrachloroethylene; toluene; toluene-2,4-diisocyanate; and 1,3-xylene. Recommendations are made regarding the expected value and variance in these values for use in exposure models.

  16. IN SITU REMEDIATION OF CONTAMINATED SEDIMENTS - ACTIVE CAPPING TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Knox, A.; Roberts, J.; Paller, M.; Reible, D.

    2010-09-02

    Active capping is a relatively new approach for treating contaminated sediments. It involves applying chemically reactive amendments to the sediment surface. The main role of active caps is to stabilize contaminants in contaminated sediments, lower the bioavailable pool of contaminants, and reduce the release of contaminants to the water column. Metals are common contaminants in many marine and fresh water environments as a result of industrial and military activities. The mobile, soluble forms of metals are generally considered toxic. Induced chemical precipitation of these metals can shift toxic metals from the aqueous phase to a solid, precipitated phase which is often less bioavailable. This approach can be achieved through application of sequestering agents such as rock phosphates, organoclays, zeolites, clay minerals, and biopolymers (e.g., chitosan) in active capping technology. Active capping holds great potential for a more permanent solution that avoids residual risks resulting from contaminant migration through the cap or breaching of the cap. In addition to identifying superior active capping agents, research is needed to optimize application techniques, application rates, and amendment combinations that maximize sequestration of contaminants. A selected set of active capping treatment technologies has been demonstrated at a few sites, including a field demonstration at the Savannah River Site, Aiken, SC. This demonstration has provided useful information on the effects of sequestering agents on metal immobilization, bioavailability, toxicity, and resistance to mechanical disturbance.

  17. In Situ Remediation Of Contaminated Sediments - Active Capping Technology

    International Nuclear Information System (INIS)

    Knox, A.; Roberts, J.; Paller, M.; Reible, D.

    2010-01-01

    Active capping is a relatively new approach for treating contaminated sediments. It involves applying chemically reactive amendments to the sediment surface. The main role of active caps is to stabilize contaminants in contaminated sediments, lower the bioavailable pool of contaminants, and reduce the release of contaminants to the water column. Metals are common contaminants in many marine and fresh water environments as a result of industrial and military activities. The mobile, soluble forms of metals are generally considered toxic. Induced chemical precipitation of these metals can shift toxic metals from the aqueous phase to a solid, precipitated phase which is often less bioavailable. This approach can be achieved through application of sequestering agents such as rock phosphates, organoclays, zeolites, clay minerals, and biopolymers (e.g., chitosan) in active capping technology. Active capping holds great potential for a more permanent solution that avoids residual risks resulting from contaminant migration through the cap or breaching of the cap. In addition to identifying superior active capping agents, research is needed to optimize application techniques, application rates, and amendment combinations that maximize sequestration of contaminants. A selected set of active capping treatment technologies has been demonstrated at a few sites, including a field demonstration at the Savannah River Site, Aiken, SC. This demonstration has provided useful information on the effects of sequestering agents on metal immobilization, bioavailability, toxicity, and resistance to mechanical disturbance.

  18. Environmental contaminants of emerging concern in seafood--European database on contaminant levels.

    Science.gov (United States)

    Vandermeersch, Griet; Lourenço, Helena Maria; Alvarez-Muñoz, Diana; Cunha, Sara; Diogène, Jorge; Cano-Sancho, German; Sloth, Jens J; Kwadijk, Christiaan; Barcelo, Damia; Allegaert, Wim; Bekaert, Karen; Fernandes, José Oliveira; Marques, Antonio; Robbens, Johan

    2015-11-01

    Marine pollution gives rise to concern not only about the environment itself but also about the impact on food safety and consequently on public health. European authorities and consumers have therefore become increasingly worried about the transfer of contaminants from the marine environment to seafood. So-called "contaminants of emerging concern" are chemical substances for which no maximum levels have been laid down in EU legislation, or substances for which maximum levels have been provided but which require revision. Adequate information on their presence in seafood is often lacking and thus potential risks cannot be excluded. Assessment of food safety issues related to these contaminants has thus become urgent and imperative. A database (www.ecsafeseafooddbase.eu), containing available information on the levels of contaminants of emerging concern in seafood and providing the most recent data to scientists and regulatory authorities, was developed. The present paper reviews a selection of contaminants of emerging concern in seafood including toxic elements, endocrine disruptors, brominated flame retardants, pharmaceuticals and personal care products, polycyclic aromatic hydrocarbons and derivatives, microplastics and marine toxins. Current status on the knowledge of human exposure, toxicity and legislation are briefly presented and the outcome from scientific publications reporting on the levels of these compounds in seafood is presented and discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Selective Detection of Target Volatile Organic Compounds in Contaminated Humid Air Using a Sensor Array with Principal Component Analysis

    Science.gov (United States)

    Itoh, Toshio; Akamatsu, Takafumi; Tsuruta, Akihiro; Shin, Woosuck

    2017-01-01

    We investigated selective detection of the target volatile organic compounds (VOCs) nonanal, n-decane, and acetoin for lung cancer-related VOCs, and acetone and methyl i-butyl ketone for diabetes-related VOCs, in humid air with simulated VOC contamination (total concentration: 300 μg/m3). We used six “grain boundary-response type” sensors, including four commercially available sensors (TGS 2600, 2610, 2610, and 2620) and two Pt, Pd, and Au-loaded SnO2 sensors (Pt, Pd, Au/SnO2), and two “bulk-response type” sensors, including Zr-doped CeO2 (CeZr10), i.e., eight sensors in total. We then analyzed their sensor signals using principal component analysis (PCA). Although the six “grain boundary-response type” sensors were found to be insufficient for selective detection of the target gases in humid air, the addition of two “bulk-response type” sensors improved the selectivity, even with simulated VOC contamination. To further improve the discrimination, we selected appropriate sensors from the eight sensors based on the PCA results. The selectivity to each target gas was maintained and was not affected by contamination. PMID:28753948

  20. A comparative study on laser induced shock cleaning of radioactive contaminants in air and water

    Science.gov (United States)

    Kumar, Aniruddha; Prasad, Manisha; Bhatt, R. B.; Behere, P. G.; Biswas, D. J.

    2018-03-01

    Efficient removal of Uranium-di-oxide (UO2) particulates from stainless steel surface was effected by Nd-YAG laser induced plasma shock waves in air as well as in water environment. The propagation velocity of the generated shock wave was measured by employing the photo-acoustic probe deflection method. Monitoring of the alpha activity of the sample with a ZnS (Ag) scintillation detector before and after the laser exposure allowed the estimation of decontamination efficiency defined as the percentage removal of the initial activity. Experiments were carried out to study the effect of laser pulse energy, number of laser exposures, orientation of the sample, the separation between the substrate surface and the onset point of the shock wave on the de-contamination efficiency. The most optimised cleaning was found to occur when the laser beam impinged normally on the sample that was immersed in water and placed at a distance of ∼0.7 mm from the laser focal spot. Analysis of the cleaned surface by optical microscopes established that laser induced shock cleaning in no way altered the surface property. The shock force generated in both air and water has been estimated theoretically and has been found to exceed the Van der Waal's binding force for spherical contaminant particulate.

  1. Extensive Viable Middle East Respiratory Syndrome (MERS) Coronavirus Contamination in Air and Surrounding Environment in MERS Isolation Wards.

    Science.gov (United States)

    Kim, Sung-Han; Chang, So Young; Sung, Minki; Park, Ji Hoon; Bin Kim, Hong; Lee, Heeyoung; Choi, Jae-Phil; Choi, Won Suk; Min, Ji-Young

    2016-08-01

    The largest outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) outside the Middle East occurred in South Korea in 2015 and resulted in 186 laboratory-confirmed infections, including 36 (19%) deaths. Some hospitals were considered epicenters of infection and voluntarily shut down most of their operations after nearly half of all transmissions occurred in hospital settings. However, the ways that MERS-CoV is transmitted in healthcare settings are not well defined. We explored the possible contribution of contaminated hospital air and surfaces to MERS transmission by collecting air and swabbing environmental surfaces in 2 hospitals treating MERS-CoV patients. The samples were tested by viral culture with reverse transcription polymerase chain reaction (RT-PCR) and immunofluorescence assay (IFA) using MERS-CoV Spike antibody, and electron microscopy (EM). The presence of MERS-CoV was confirmed by RT-PCR of viral cultures of 4 of 7 air samples from 2 patients' rooms, 1 patient's restroom, and 1 common corridor. In addition, MERS-CoV was detected in 15 of 68 surface swabs by viral cultures. IFA on the cultures of the air and swab samples revealed the presence of MERS-CoV. EM images also revealed intact particles of MERS-CoV in viral cultures of the air and swab samples. These data provide experimental evidence for extensive viable MERS-CoV contamination of the air and surrounding materials in MERS outbreak units. Thus, our findings call for epidemiologic investigation of the possible scenarios for contact and airborne transmission, and raise concern regarding the adequacy of current infection control procedures. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  2. Estudo de metais e de substâncias tóxicas em brinquedos Toys contamined by toxic substances

    Directory of Open Access Journals (Sweden)

    Josiane Zini

    2009-01-01

    Full Text Available The main goal of the present study is the analysis of toxic elements in plastic toys commercialized in Brazil. Metals like cadmium, lead, chromium, zinc, and aluminum, along with organic substances, such as phthalates, were identified in different toys by quantitative analytical techniques. Traces of thorium were detected in one of the studied samples. Although the measured radioactive dose was rather low, the presence of such a radioactive contaminant is against to the International Agency of Atomic Energy regulations. Similar toys manufactured in Brazil were analyzed and found to observe the standards defined by the National Institute of Metrology (Inmetro.

  3. Air permitting of IGCC plants

    Energy Technology Data Exchange (ETDEWEB)

    Chitikela, S.R.

    2007-07-01

    The IGCC process is, currently, the preferred choice over conventional thermal power production in regard to cleanup of fuel and significantly reduced contaminant emissions. The air permitting requirements include the review of: feed preparation and PM emissions; feed gasification and contaminant emissions; elemental sulfur recovery and SO{sub 2} emissions; options for carbon-dioxide recovery; syngas characteristics for combustion; CT design and combustion mechanisms; air contaminant emissions of CT; controlled CT emissions of nitrogen-oxides and carbon-monoxide gases using the SCR and oxidation catalysts, respectively; and, emission of volatile organic compounds (VOCs), and hazardous air pollutants (HAPs). However, the IGCC processes are being rigorously reviewed for the system integration and reliability, and significant reduction of air contaminant emissions (including the greenhouse gases). This paper included a review of IGCC air contaminant emission rates, and various applicable regulatory requirements, such as NSR (New Source Review), NSPS (New Source Performance Standards), and MACT (Maximum Achievable Control Technology). The IGCC facility's NOX, CO, SO{sub 2}, PM, VOCs, and HAPs emission rates would be significantly low. Thus, effective, construction and installation, and operation air permits would be necessary for IGCC facilities.

  4. System calibration for air control of radioactive gases [contamination control]; Kalibracija sistema za kontrolu vazduha na radioaktivne gasove

    Energy Technology Data Exchange (ETDEWEB)

    Zecevic, V; Milosevic, M [Institute of Nuclear Sciences Boris Kidric, Reaktor RA, Vinca, Beograd (Serbia and Montenegro)

    1963-02-15

    Testing of the system for air contamination control at the RA reactor was done and calibrated by Ar{sup 41}. This report contains the report on testing and calibration. This activity was necessary in order to achieve its performance with existing dosimetry system in the RA reactor building.

  5. Photo-acoustic sensor for detection of oil contamination in compressed air systems.

    Science.gov (United States)

    Lassen, Mikael; Harder, David Baslev; Brusch, Anders; Nielsen, Ole Stender; Heikens, Dita; Persijn, Stefan; Petersen, Jan C

    2017-02-06

    We demonstrate an online (in-situ) sensor for continuous detection of oil contamination in compressed air systems complying with the ISO-8573 standard. The sensor is based on the photo-acoustic (PA) effect. The online and real-time PA sensor system has the potential to benefit a wide range of users that require high purity compressed air. Among these are hospitals, pharmaceutical industries, electronics manufacturers, and clean room facilities. The sensor was tested for sensitivity, repeatability, robustness to molecular cross-interference, and stability of calibration. Explicit measurements of hexane (C6H14) and decane (C10H22) vapors via excitation of molecular C-H vibrations at approx. 2950 cm-1 (3.38 μm) were conducted with a custom made interband cascade laser (ICL). For the decane measurements a (1 σ) standard deviation (STD) of 0.3 ppb was demonstrated, which corresponds to a normalized noise equivalent absorption (NNEA) coefficient for the prototype PA sensor of 2.8×10-9 W cm-1 Hz1/2.

  6. Silent Discharge Plasma Technology for the Treatment of Air Toxics and Other Applications

    Energy Technology Data Exchange (ETDEWEB)

    Rosocha, Louis A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chase, Peter J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gross, Michael P. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    1998-09-21

    Under this CRADA, the Los Alamos National Laboratory (LANL) and High Mesa Technologies, Inc. (HMT) carried out a joint project on the development of the silent discharge plasma (SDP) technology for the treatment of hazardous air pollutants and other hazardous or toxic chemicals. The project had two major components: a technology-demonstration part and a scale-up and commercialization part. In the first part, a small-scale, mobile SDP plasma processor, which was being developed under a CRADA with the Electric Power Research Institute (EPRI) was the mobile equipment was modified for higher capacity service and employed for an innovative remediation technologies demonstration on soil-vapor extraction off-gases at the McClellan Air Force Base near Sacramento, CA. The performance of the SDP system for the variety of volatile organic compounds (VOCs) encountered at the McClellan site was sufficiently promising to the project HMT and LANL worked together to formulate a scale-up strategy and commercialization/manufacturing plan, and to design a prototype scaled-up SDP unit. HMT and LANL are now in the final stages of completing a licensing agreement for the technology and HMT is in the process of raising funds to engineer and manufacture commercial prototype SDP equipment focused on stack-gas emissions control and environmental remediation. HMT, in collaboration with another Northern New Mexico business, Coyote Aerospace, has also been successful in receiving a Phase I Small Business Innovative Research (SBIR) award from the Army Research Office to develop, design, and construct a small non-thermal plasma reactor for laboratory studies ("Non-Thermal Plasma Reactor for Control of Fugitive Emissions of Toxic Gases")

  7. NSF-RANN trace contaminants abstracts

    International Nuclear Information System (INIS)

    Copenhaver, E.D.; Harnden, D.S.

    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

  8. Phytochemicals reduce aflatoxin-induced toxicity in chicken embryos

    Science.gov (United States)

    Aflatoxins (AF) are toxic metabolites produced by molds, Aspergillus flavus and Aspergillus parasiticus, which frequently contaminate poultry feed ingredients. Ingestion of AF-contaminated feed by chickens leads to deleterious effects, including decreased bird performance and reduced egg production....

  9. Air toxics emission from an IGCC process

    Energy Technology Data Exchange (ETDEWEB)

    Mojtahedi, W; Hovath, A [Carbona Inc, Helsinki (Finland); Hinderson, A [Vattenfall Utveckling (Sweden); Nykaenen, J; Hoffren, H [Imatran Voima Oy, Vantaa (Finland); Nieminen, M; Kurkela, E [VTT, Espoo (Finland)

    1997-10-01

    The emissions of 12 toxic trace element from a coal-fired IGCC plant were calculated based on thermodynamic equilibrium in the gas phase and some of the results published. The theoretical calculations were extended to include some other fuels as well as mixture of some of these fuels. The combustion of the product gas in the gas turbine is also considered. These simulations correspond to gasification of the fuel at 850-1050 deg C (depending on the fuel) and 1823 bar pressure. The gas composition was taken from the measured data as far as possible. In the absence of experimental data, a computer code developed for the U-Gas gasifier was used to determine the fuel gas composition. The gas was then cooled to 550 deg C in the gas cooler and filtered at this same temperature and burned in the gas turbine with an air ratio of 3.2. The results of these simulations are compared with the measured data of an experimental program designed to measure the emissions of a few selected trace elements from a 15 MW,h pressurized fluidized bed gasification pilot plant. The pilot plant was equipped with an advanced hot gas cleanup train which includes a two fluidized-bed reactor system for high-temperature, high-pressure external sulfur removal and a filtration unit housing porous, rigid ceramic candle filters. The trace element concentrations in the fuel, bottom ash, and filter ash are determined and the results compared with EPA regulatory levels

  10. Thermal oxidation for air toxics control

    International Nuclear Information System (INIS)

    Pennington, R.L.

    1991-01-01

    The Administration projects annual expenditures of $1.1 billion by 1995, increasing to $6.7 billion by 2005, in order to comply with the new Clean Air Act Title III hazardous air pollutant requirements. The Title III requirements include 189 hazardous air pollutants which must be reduced or eliminated by 2003. Twenty of the 189 listed pollutants account for approximately 75 percent of all hazardous air pollutant emissions. Ninety percent of these 20 pollutants can be effectively controlled through one or mote of the thermal oxidation technologies. This paper reports that the advantages and disadvantages of each thermal oxidation technology vary substantially and must be reviewed for each application in order to establish the most effective thermal oxidation solution. Effective thermal oxidation will meet MACT (maximum achievable control technology) emission standards

  11. MONITORING THE AIR FOR TOXIC AND GENOTOXIC COMPOUNDS

    Science.gov (United States)

    A time-integrated sampling system interfaced with a toxicity-based assay is reported for monitoring volatile toxic industrial chemicals (TICs). Semipermeable membrane devices (SPMDs) using dimethyl sulfoxide (DMSO) as the fill solvent accumulated each of 17 TICs from the vapor p...

  12. 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

  13. An evaluation of antifungal agents for the treatment of fungal contamination in indoor air environments.

    Science.gov (United States)

    Rogawansamy, Senthaamarai; Gaskin, Sharyn; Taylor, Michael; Pisaniello, Dino

    2015-06-02

    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 inhibit the growth

  14. Air contamination measurements for the evaluation of internal dose to workers in nuclear medicine departments

    Science.gov (United States)

    De Massimi, B.; Bianchini, D.; Sarnelli, A.; D'Errico, V.; Marcocci, F.; Mezzenga, E.; Mostacci, D.

    2017-11-01

    Radionuclides handled in nuclear medicine departments are often characterized by high volatility and short half-life. It is generally difficult to monitor directly the intake of these short-lived radionuclides in hospital staff: this makes measuring air contamination of utmost interest. The aim of the present work is to provide a method for the evaluation of internal doses to workers in nuclear medicine, by means of an air activity sampling detector, to ensure that the limits prescribed by the relevant legislation are respected. A continuous air sampling system measures isotope concentration with a Nal(TI) detector. Energy efficiency of the system was assessed with GEANT4 and with known activities of 18F. Air is sampled in a number of areas of the nuclear medicine department of the IRST-IRCCS hospital (Meldola- Italy). To evaluate committed doses to hospital staff involved (doctors, technicians, nurses) different exposure situations (rooms, times, radionuclides etc) were considered. After estimating the intake, the committed effective dose has been evaluated, for the different radionuclides, using the dose coefficients mandated by the Italian legislation. Error propagation for the estimated intake and personal dose has been evaluated, starting from measurement statistics.

  15. Effects-based spatial assessment of contaminated estuarine sediments from Bear Creek, Baltimore Harbor, MD, USA.

    Science.gov (United States)

    Hartzell, Sharon E; Unger, Michael A; McGee, Beth L; Wilson, Sacoby M; Yonkos, Lance T

    2017-10-01

    Estuarine sediments in regions with prolonged histories of industrial activity are often laden to significant depths with complex contaminant mixtures, including trace metals and persistent organic pollutants. Given the complexity of assessing risks from multi-contaminant exposures, the direct measurement of impacts to biological receptors is central to characterizing contaminated sediment sites. Though biological consequences are less commonly assessed at depth, laboratory-based toxicity testing of subsurface sediments can be used to delineate the scope of contamination at impacted sites. The extent and depth of sediment toxicity in Bear Creek, near Baltimore, Maryland, USA, was delineated using 10-day acute toxicity tests with the estuarine amphipod Leptocheirus plumulosus, and chemical analysis of trace metals and persistent organic pollutants. A gradient of toxicity was demonstrated in surface sediments with 21 of 22 tested sites differing significantly from controls. Effects were most pronounced (100% lethality) at sites proximate to a historic industrial complex. Sediments from eight of nine core samples to depths of 80 cm were particularly impacted (i.e., caused significant lethality to L. plumulosus) even in locations overlain with relatively non-toxic surface sediments, supporting a conclusion that toxicity observed at the surface (top 2 cm) does not adequately predict toxicity at depth. In seven of nine sites, toxicity of surface sediments differed from toxicity at levels beneath by 28 to 69%, in five instances underestimating toxicity (28 to 69%), and in two instances overestimating toxicity (44 to 56%). Multiple contaminants exceeded sediment quality guidelines and correlated positively with toxic responses within surface sediments (e.g., chromium, nickel, polycyclic aromatic hydrocarbon (PAH), total petroleum hydrocarbon). Use of an antibody-based PAH biosensor revealed that porewater PAH concentrations also increased with depth at most sites. This

  16. Assessing the bioavailability and risk from metal-contaminated ...

    Science.gov (United States)

    Exposure to contaminated soil and dust is an important pathway in human health risk assessment. Physical and chemical characteristics, as well as biological factors, determine the bioaccessibility/bioavailability of soil and dust contaminants. Within a single sample, contamination may arise from multiple sources of toxic elements that may exist as different forms (species) which impact bioavailability. In turn, the bioaccessibility/bioavailability of soil and dust contaminants has a direct impact on human health risk assessment and risk management practices. Novel research efforts focusing on development and application of in vitro and in vivo methods to measure the bioaccessibility/bioavailability of metal contaminated soils have advanced in the past few years. The objective of this workshop was to focus on recent developments in assessing the bioaccessibility/bioavailability of arsenic contaminated soils, metal contamination in urban residences in Canada and potential children’s exposures to toxic elements in house dust, a community-based study known as the West Oakland Residential Lead Assessment , studies of the bioavailability of soil cadmium, chromium, nickel and mercury and human exposures to contaminated Brownfield soils. These presentations covered issues related to human health and bioavailability along with the most recent studies on community participation in assessing metal contamination, studies of exposures to residential contamination, and

  17. Arsenic: A Review of the Element's Toxicity, Plant Interactions, and Potential Methods of Remediation.

    Science.gov (United States)

    Hettick, Bryan E; Cañas-Carrell, Jaclyn E; French, Amanda D; Klein, David M

    2015-08-19

    Arsenic is a naturally occurring element with a long history of toxicity. Sites of contamination are found worldwide as a result of both natural processes and anthropogenic activities. The broad scope of arsenic toxicity to humans and its unique interaction with the environment have led to extensive research into its physicochemical properties and toxic behavior in biological systems. The purpose of this review is to compile the results of recent studies concerning the metalloid and consider the chemical and physical properties of arsenic in the broad context of human toxicity and phytoremediation. Areas of focus include arsenic's mechanisms of human toxicity, interaction with plant systems, potential methods of remediation, and protocols for the determination of metals in experimentation. This assessment of the literature indicates that controlling contamination of water sources and plants through effective remediation and management is essential to successfully addressing the problems of arsenic toxicity and contamination.

  18. The use of bioassays to assess the toxicity of sediment in an acid ...

    African Journals Online (AJOL)

    Exposure of river sediment from 7 sampling sites to these bioassays provided an eco-toxicological estimation of the acute toxicity and chronic toxicity emanating from the contaminated sediments. Physico-chemical analyses revealed higher levels of sediment contamination closer to the mine. The bioassays displayed a ...

  19. Owls as biomonitors of environmental contamination

    Science.gov (United States)

    Steven R. Sheffield

    1997-01-01

    Much like the caged canary used by miners, a plethora of wildlife species have been promoted as biomonitors of environmental contamination. These species provide an "early warning system" for toxic contaminants in the environment. Species promoted as useful biomonitors share many common life history characters, such as wide distribution, territorial, non-...

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

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    An environmental investigation of ground water conditions has been undertaken at Wright-Patterson Air Force Base (WPAFB), Ohio to obtain data to assist in the evaluation of a potential removal action to prevent, to the extent practicable, migration of the contaminated ground water across Base boundaries. Field investigations were limited to the central section of the southwestern boundary of Area C and the Springfield Pike boundary of Area B. Further, the study was limited to a maximum depth of 150 feet below grade. Three primary activities of the field investigation were: (1) installation of 22 monitoring wells, (2) collection and analysis of ground water from 71 locations, (3) measurement of ground water elevations at 69 locations. Volatile organic compounds including trichloroethylene, perchloroethylene, and/or vinyl chloride were detected in concentrations exceeding Maximum Contaminant Levels (MCL) at three locations within the Area C investigation area. Ground water at the Springfield Pike boundary of Area B occurs in two primary units, separated by a thicker-than-expected clay layers. One well within Area B was determined to exceed the MCL for trichloroethylene.

  1. Occurrence, Toxicity, and Analysis of Major Mycotoxins in Food

    Directory of Open Access Journals (Sweden)

    Ahmad Alshannaq

    2017-06-01

    Full Text Available Mycotoxins are toxic secondary metabolites produced by certain filamentous fungi (molds. These low molecular weight compounds (usually less than 1000 Daltons are naturally occurring and practically unavoidable. They can enter our food chain either directly from plant-based food components contaminated with mycotoxins or by indirect contamination from the growth of toxigenic fungi on food. Mycotoxins can accumulate in maturing corn, cereals, soybeans, sorghum, peanuts, and other food and feed crops in the field and in grain during transportation. Consumption of mycotoxin-contaminated food or feed can cause acute or chronic toxicity in human and animals. In addition to concerns over adverse effects from direct consumption of mycotoxin-contaminated foods and feeds, there is also public health concern over the potential ingestion of animal-derived food products, such as meat, milk, or eggs, containing residues or metabolites of mycotoxins. Members of three fungal genera, Aspergillus, Fusarium, and Penicillium, are the major mycotoxin producers. While over 300 mycotoxins have been identified, six (aflatoxins, trichothecenes, zearalenone, fumonisins, ochratoxins, and patulin are regularly found in food, posing unpredictable and ongoing food safety problems worldwide. This review summarizes the toxicity of the six mycotoxins, foods commonly contaminated by one or more of them, and the current methods for detection and analysis of these mycotoxins.

  2. Emerging Fusarium and Alternaria Mycotoxins: Occurrence, Toxicity and Toxicokinetics

    Directory of Open Access Journals (Sweden)

    Sophie Fraeyman

    2017-07-01

    Full Text Available Emerging Fusarium and Alternaria mycotoxins gain more and more interest due to their frequent contamination of food and feed, although in vivo toxicity and toxicokinetic data are limited. Whereas the Fusarium mycotoxins beauvericin, moniliformin and enniatins particularly contaminate grain and grain-based products, Alternaria mycotoxins are also detected in fruits, vegetables and wines. Although contamination levels are usually low (µg/kg range, higher contamination levels of enniatins and tenuazonic acid may occasionally occur. In vitro studies suggest genotoxic effects of enniatins A, A1 and B1, beauvericin, moniliformin, alternariol, alternariol monomethyl ether, altertoxins and stemphyltoxin-III. Furthermore, in vitro studies suggest immunomodulating effects of most emerging toxins and a reproductive health hazard of alternariol, beauvericin and enniatin B. More in vivo toxicity data on the individual and combined effects of these contaminants on reproductive and immune system in both humans and animals is needed to update the risk evaluation by the European Food Safety Authority. Taking into account new occurrence data for tenuazonic acid, the complete oral bioavailability, the low total body clearance in pigs and broiler chickens and the limited toxicity data, a health risk cannot be completely excluded. Besides, some less known Alternaria toxins, especially the genotoxic altertoxins and stemphyltoxin III, should be incorporated in risk evaluation as well.

  3. 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...... quality with personalized and mixing ventilation was higher or at least similar compared to mixing ventilation alone. In the case of PV combined with displacement ventilation, the interaction caused mixing of the room air, an increase in the transport of bioeffluents and exhaled air between occupants and...... 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...

  4. Sediment toxicity testing with the amphipod Ampelisca abdita in Calcasieu Estuary, Louisiana

    Science.gov (United States)

    Redmond, M.S.; Crocker, P.A.; McKenna, K.M.; Petrocelli, E.A.; Scott, K.J.; Demas, C.R.

    1996-01-01

    Discharges from chemical and petrochemical manufacturing facilities have contaminated portions of Louisiana's Calcasieu River estuary with a variety of organic and inorganic contaminants. As part of a special study, sediment toxicity testing was conducted to assess potential impact to the benthic community. Ten-day flow-through sediment toxicity tests with the amphipod Ampelisca abdita revealed significant toxicity at 68% (26 of 38) of the stations tested. A. abdita mortality was highest in the effluent-dominated bayous, which are tributaries to the Calcasieu River. Mortality was correlated with total heavy metal and total organic compound concentrations in the sediments. Ancillary experiments showed that sediment interstitial water salinity as low as 2.5 o/o-o did not significantly affect A. abdita's, response in the flow-through system; sediment storage for 7 weeks at 4??C did not significantly affect toxicity. Sediment toxicity to A. abdita was more prevalent than receiving water toxicity using three short-term chronic bioassays. Results suggest that toxicity testing using this amphipod is a valuable tool when assessing sediments containing complex contaminant mixtures and for assessing effects of pollutant loading over time. In conjunction with chemical analyses, the testing indicated that the effluent-dominated, brackish bayous (Bayou d'Inde and Bayou Verdine) were the portions of the estuary most impacted by toxicity.

  5. [Investigation of microbial contamination of the air and equipment of a biological waste water purification station].

    Science.gov (United States)

    Alikbaeva, L A; Figurovskiĭ, A P; Vasil'ev, O D; Ermolaev-Makovskiĭ, M A; Merkur'eva, M A

    2010-01-01

    The paper describes the results of a study of ambient air microbiological pollution in the working premises and equipment surfaces in the main shops of the biological waste water purification station of a cardboard-polygraphic plant. The findings suggest that there is high microbial contamination of the working environment, which should be born in mind on developing measures to optimize working conditions and on studying morbidity rates among the workers.

  6. The prevalence of toxic hotspots in former Soviet countries

    International Nuclear Information System (INIS)

    Sharov, Petr; Dowling, Russell; Gogishvili, Megi; Jones, Barbara; Caravanos, Jack; McCartor, Andrew; Kashdan, Zachary; Fuller, Richard

    2016-01-01

    Using a global database of contaminated sites, toxic hotspots in eight former Soviet countries were analyzed to identify the prevalence, types and sources of toxic pollution, as well as their associated potential public health impacts. For this analysis, polluted sites in Armenia, Azerbaijan, Kazakhstan, Kyrgyzstan, Russia, Tajikistan, Ukraine, and Uzbekistan were compiled and analyzed. The levels of contamination of seven key pollutants were assessed in each country. 424 contaminated sites were identified using data from Blacksmith Institute. Pesticides, lead (Pb), radioactive metals, arsenic (As), mercury (Hg), chromium (Cr), and cadmium (Cd) were the most commonly identified key pollutants. Collectively, these sites pose health risks to an estimated 6.2 million residents. The existing data on toxic hotspots in former Soviet countries likely captures only a small percentage of actual contaminated sites, but suggests potentially severe public health consequences. Additional assessments are needed to understand the risks posed by toxic pollution in the region. - Highlights: • Pollution in 8 former Soviet countries poses a health risk to 6.2 million residents. • The most commonly found key pollutants are pesticides, lead, arsenic, and cadmium. • The majority of sites can be traced to Soviet legacy pollution. - 424 sites were identified in the analysis. Pesticides, Pb, radioactive metals, As, Hg, Cr, and Cd were the most common key pollutants, collectively affecting 6.2 million people.

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

    International Nuclear Information System (INIS)

    Eberhart, C.F.

    1998-01-01

    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 ( 234 U, 235 U, 238 U), plutonium ( 238 Pu, 239/249 Pu), and americium ( 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

  8. Glyphosate contaminated soil remediation by atmospheric pressure dielectric barrier discharge plasma and its residual toxicity evaluation.

    Science.gov (United States)

    Wang, Tiecheng; Ren, Jingyu; Qu, Guangzhou; Liang, Dongli; Hu, Shibin

    2016-12-15

    Glyphosate was one of the most widely used herbicides in the world. Remediation of glyphosate-contaminated soil was conducted using atmospheric pressure dielectric barrier discharge (DBD) plasma. The feasibility of glyphosate degradation in soil was explored, and the soil leachate toxicity after remediation was assessed via a seed germination test. The experimental results showed that approximately 93.9% of glyphosate was degraded within 45min of DBD plasma treatment with an energy yield of 0.47gkWh -1 , and the degradation process fitted the first-order kinetic model. Increasing the discharge voltage and decreasing the organic matter content of the soil were both found to facilitate glyphosate degradation. There existed appropriate soil moisture to realize high glyphosate degradation efficiency. Glyphosate mineralization was confirmed by changes of total organic carbon (TOC), chemical oxygen demand (COD), PO 4 3- and NO 3 - . The degradation intermediates including glycine, aminomethylphosphonic acid, acetic acid, formic acid, PO 4 3- and NO 3 - , CO 2 and CO were observed. A possible pathway for glyphosate degradation in the soil using this system was proposed. Based on the soil leachate toxicity test using wheat seed germination, the soil did not exhibit any hazardous effects following high-efficiency glyphosate degradation. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Guidance for air sampling at nuclear facilities

    International Nuclear Information System (INIS)

    Breslin, A.J.

    1976-11-01

    The principal uses of air sampling at nuclear facilities are to monitor general levels of radioactive air contamination, identify sources of air contamination, and evaluate the effectiveness of contaminant control equipment, determine exposures of individual workers, and provide automatic warning of hazardous concentrations of radioactivity. These applications of air sampling are discussed with respect to standards of occupational exposure, instrumentation, sample analysis, sampling protocol, and statistical treatment of concentration data. Emphasis is given to the influence of spacial and temporal variations of radionuclide concentration on the location, duration, and frequency of air sampling

  10. Projections of air toxic emissions from coal-fired utility combustion: Input for hazardous air pollutant regulators

    International Nuclear Information System (INIS)

    Szpunar, C.B.

    1993-01-01

    The US Environmental Protection Agency (EPA) is required by the 1990 CAAA to promulgate rules for all ''major'' sources of any of these HAPs. According to the HAPs section of the new Title III, any stationary source emitting 10 tons per year (TPY) of one HAP or 25 TPY of a combination of HAPs will be considered and designated a major source. In contrast to the original National Emission Standards for Hazardous Air Pollutants (NESHAP), which were designed to protect public health to ''an ample margin of safety,'' the new Title III, in its first phase, will regulate by industrial category those sources emitting HAPs in excess of the 10/25-TPY threshold levels, regardless of health risks. The trace elements normally associated with coal mineral matter and the various compounds formed during coal combustion have the potential to produce hazardous air toxic emissions from coal-fired electric utilities. Under Title III, the EPA is required to perform certain studies, prior to any regulation of electric utilities; these studies are currently underway. Also, the US Department of Energy (DOE) maintains a vested interest in addressing those energy policy questions affecting electric utility generation, coal mining, and steel producing critical to this country's economic well-being, where balancing the costs to the producers and users of energy with the benefits of environmental protection to the workers and the general populace remains of significant concern

  11. Seasonal variation of sediment toxicity in the Rivers Dommel and Elbe

    International Nuclear Information System (INIS)

    Hsu, P.; Matthaei, A.; Heise, S.; Ahlf, W.

    2007-01-01

    Contaminated sediment in the river basin has become a source of pollution with increasing importance to the aquatic ecosystem downstream. To monitor the temporal changes of the sediment bound contaminants in the River Elbe and the River Dommel monthly toxicity tests were applied to layered sediment and river water samples over the course of 10 months. There is an indication that contaminated sediments upstream adversely affected sediments downstream, but this process did not cause a continuous increase of sediment toxicity. A clear decrease of toxic effects in water and upper layer sediment was observed at the River Elbe station in spring related to high water discharge and algal blooms. The less obvious variation of sediment toxicity in the River Dommel could be explained by stable hydrological conditions. Future monitoring programmes should promote a more frequent and intensive sampling regime during these particular events for ecotoxicological evaluation. - Significant impacts of hydrological and biological factors on the ecotoxicological quality in two European rivers (Elbe and Dommel)

  12. Hot air vapor extraction system for remediation of petroleum contaminated sites

    International Nuclear Information System (INIS)

    Pal, D.; Karr, L.; Fann, S.; Mathews, A.P.; Price, P.A.; Linginemi, S.

    1996-01-01

    This paper describes the results of a demonstration of a technology entitled ''Hot Air Vapor Extraction (HAVE)'' at the Hydrocarbon National Test Site (HNTS), Port Hueneme, California. The demonstration of the HAVE technology at HNTS was conducted over a 3-month period between August 21, 1995 and November 22, 1995 and the lessons learned from the demonstration are discussed in details to guide the Department of Defense decision makers in analyzing the applicability of this technology to their contaminated sites. This technology demonstration was conducted under the Department of Defense Strategic Environmental Research and Development Program (SERDP) as part of the National Environmental Technology Demonstration Program (NETDP). The primary objectives of the demonstration were to (1) validate the efficacy of the HAVE technology to treat a wide range of hydrocarbons contaminated soils, (2) gather data to estimate treatment costs, and (3) develop engineering guidance needed to apply this remediation technology DoD-wide. Test runs were made on 5 different treatment cells containing various fuel hydrocarbons, ranging from gasoline to heavier petroleum fractions such as lubricating oil. Computer modeling was conducted to analyze the test results and also to optimize the HAVE system design. An economic analysis conducted for various remediation project sizes ranging from 750 to 9,000 cubic yards, the per cubic yard treatment costs are found to vary from $64.05 down to $36.54 respectively

  13. Correlation of BTEX levels and toxicity of condensate contaminated groundwater

    International Nuclear Information System (INIS)

    Headley, J.; Goudey, S.; Birkholz, D.; Hardisty, P.

    1995-01-01

    The concentration of BTEX was determined for 60 groundwater samples collected from 6 gas plants in Western Canada, using conventional purge-and-trap GC/MS procedures. The gas plants were selected to cover different types of operations with different amine process chemicals employed for the sweetening of the raw sour-gas condensates. Aliquots of the ground water samples were subjected to toxicity screening tests, specifically, (a) bacterial luminescence (microtox); (b) daphnia mortality and (c) fathead minnow mortality. For the toxicity tests, sample handling procedures were developed to minimize the loss of volatile organics during the experiments. To account for possible losses, the levels of BTEX were monitored at the start and upon completion of these tests. The results indicated that the toxicity of the groundwater was in general, well correlated to the concentration of BTEX (primarily xylene). Approximately 5% of the samples, however, were observed to be toxic although the concentration of BTEX were below the method detection limit (1 microg/1). Thiophenic volatile organics were implicated for the latter. Based on the laboratory results, the remediation of BTEX is expected to correlate with the removal of the toxicity of the groundwater. These findings are of direct relevance to present technologies employed for remediation of ground water at the Sourgas plants

  14. study on trace contaminants control assembly for sealed environment chamber

    Science.gov (United States)

    Pang, L. P.; Wang, J.; Liu, L. K.; Liu, H.

    The biological and Physicochemical P C life support technologies are all important parts to establish a human Closed Ecological Life Support System CELSS for long-duration mission The latter has the advantages of lower power consumption lower mass and higher efficiency therefore researchers often incorporate the use of biological systems with P C life support technologies to continuously recycle air water and part of the solid waste stream generated such as the Russian BLSS and the NASA-sponsored Lunar-Mars Life Support Test Project LMLSTP In short these tests were very successful in integrating biological and P C life support technologies for long-duration life support Therefore we should use a combination of integrated biological with P C life support technologies in a human CELSS Human construction materials plants animals and soils release much trace toxic gases in a CELSS and they will inhibit plant growth and badly affect human health when their concentrations rise over their threshold levels The effect of biological trace contaminant control technologies is slower especially for a human sealed chamber because human produce much more methane and other contaminants A regenerative Trace Contaminant Control Subsystem TCCS with P C technology is a more important part in this case to control quickly the airborne contaminants levels and assure human in good condition in a sealed chamber This paper describes a trace contaminant control test facility incorporated a 8 m3 sealed environment chamber a regenerative TCCS with P C

  15. Reduction of Fumonisin Toxicity by Extrusion and Nixtamalization (Alkaline Cooking).

    Science.gov (United States)

    Voss, Kenneth; Ryu, Dojin; Jackson, Lauren; Riley, Ronald; Gelineau-van Waes, Janee

    2017-08-23

    Fumonisins are mycotoxins found in corn. They are toxic to animals and cause cancer in rodents and neural tube defects in LM/Bc mice. Reducing their concentrations in corn-based foods is therefore desirable. Chemical analysis or in vitro bioassays of food extracts might not detect toxic fumonisin reaction products that are unknown or unextractable from food matrices, thus potentially underestimating in vivo toxicity. The effectiveness of two common cooking methods, extrusion and nixtamalization (alkaline cooking), to reduce the toxicity of fumonisin-contaminated corn grits (extrusion) and whole kernel corn (nixtamalization) was shown by means of rat feeding bioassays using fumonisin-specific kidney effects as indicators of potential toxicity. A third bioassay showed that in contrast to fumonisin B 1 (FB 1 ), hydrolyzed fumonisin B 1 (HFB 1 ; formed from FB 1 during nixtamalization) did not cause neural tube defects in LM/Bc mice. The findings indicate that extrusion and nixtamalization reduce the potential toxicity of FB 1 -contaminated corn.

  16. The relevance of national and international initiatives on toxic substances to the management of hazardous air pollutants in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Buccini, J.

    2001-03-30

    The Canadian Council of Ministers of the Environment (CCME), seeking guidance on current and emerging national and international initiatives, activities, and programs that could impact on the management of hazardous air pollutants (HAPs) in Canada, commissioned the author to prepare this document. In this report, HAPs are defined as toxic substances subject to airborne transport as a significant route of environmental distribution and/or exposure. Heavy metals and persistent organic pollutants (POPs) were included in this definition. A model, known as toxics cycle, represented the four distinct stages of the process of selecting substances for risk assessment and management: problem identification and priority setting, risk assessment, risk management, and monitoring and evaluation. A large number of international activities were reviewed, such as research, hazard and risk assessment, risk management, and monitoring and surveillance programs. The present report only deals with the programs that had been identified in the National Air Issues Coordinating Committee-Other Air Issues (NAICC-A) of the CCME report published in 1999 and which had recent or foreseen impacts. Five bi-lateral and multi-lateral agreements on persistent toxic substances, as well as national, regional and global programs, activities, and initiatives concerning the assessment of the hazards and risks of chemicals and actions were reviewed. It was recommended that initiatives at all levels continue to be monitored and that Environment Canada continue to be the conduit of information at the international level. Issues and opportunities must be identified by all jurisdictions with regard to risk management. It was suggested by the author that risk assessment be conducted by Environment Canada and the attention of the HAP group be drawn on specific topics as required. 2 tabs., 1 fig.

  17. One Health and Toxic Cyanobacteria | Science Inventory | US ...

    Science.gov (United States)

    One Health and toxic cyanobacteria Blooms of toxic freshwater blue-green algae or cyanobacteria (HABs) have been in the news after HABs associated with human and animal health problems have been reported in Florida, California and Utah during 2016. HABs occur in warm, slow moving or stagnant surface waters that are enriched with nutrients such as nitrogen and phosphorous. People are exposed to potentially toxic HABs during recreation in contaminated water, after exposure to contaminated drinking water or to blue-green algae supplements. Animals may be exposed to toxic HABs after drinking contaminated surface waters or coming into contact with HABs then ingesting cyanobacteria from their bodies during self-grooming activities. As HABs are being reported more frequently in the US, it is important for veterinarians to secure good exposure histories and to recognize the potential signs and health consequences of HAB exposures. We will review the current knowledge about human and animal health effects associated with freshwater HABs and scenarios that pose the highest risks for illnesses and deaths. This abstract does not necessarily reflect EPA policy. This is a summary of One Health and Cyanobacteria for public health and public practice veterinarians at the American Veterinary Medical Association annual convention. This product is associated with SSWR 4.01B

  18. 30 CFR 56.5005 - Control of exposure to airborne contaminants.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Control of exposure to airborne contaminants... Air Quality and Physical Agents Air Quality § 56.5005 Control of exposure to airborne contaminants. Control of employee exposure to harmful airborne contaminants shall be, insofar as feasible, by prevention...

  19. 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. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  20. Nutrients versus emerging contaminants-Or a dynamic match between subsidy and stress effects on stream biofilms.

    Science.gov (United States)

    Aristi, I; Casellas, M; Elosegi, A; Insa, S; Petrovic, M; Sabater, S; Acuña, V

    2016-05-01

    Freshwater ecosystems are threatened by multiple anthropogenic stressors, which might be differentiated into two types: those that reduce biological activity at all concentrations (toxic contaminants), and those that subsidize biological activity at low concentrations and reduce it at high concentrations (assimilable contaminants). When occurring in mixtures, these contaminants can have either antagonistic, neutral or synergistic effects; but little is known on their joint effects. We assessed the interaction effects of a mixture of assimilable and toxic contaminants on stream biofilms in a manipulative experiment using artificial streams, and following a factorial design with three nutrient levels (low, medium or high) and either presence or absence of a mixture of emerging contaminants (ciprofloxacin, erythromycin, diclofenac, methylparaben, and sulfamethoxazole). We measured biofilm biomass, basal fluorescence, gross primary production and community respiration. Our initial hypotheses were that biofilm biomass and activity would: increase with medium nutrient concentrations (subsidy effect), but decrease with high nutrient concentrations (stress effect) (i); decrease with emerging contaminants, with the minimum decrease at medium nutrient concentrations (antagonistic interaction between nutrients subsidy and stress by emerging contaminants) and the maximum decrease at high nutrient concentrations (synergistic interaction between nutrients and emerging contaminants stress) (ii). All the measured variables responded linearly to the available nutrients, with no toxic effect at high nutrient concentrations. Emerging contaminants only caused weak toxic effects in some of the measured variables, and only after 3-4 weeks of exposure. Therefore, only antagonistic interactions were observed between nutrients and emerging contaminants, as medium and high nutrient concentrations partly compensated the harmful effects of emerging contaminants during the first weeks of the

  1. Environmental Mercury and Its Toxic Effects

    Directory of Open Access Journals (Sweden)

    Kevin M. Rice

    2014-03-01

    Full Text Available Mercury exists naturally and as a man-made contaminant. The release of processed mercury can lead to a progressive increase in the amount of atmospheric mercury, which enters the atmospheric-soil-water distribution cycles where it can remain in circulation for years. Mercury poisoning is the result of exposure to mercury or mercury compounds resulting in various toxic effects depend on its chemical form and route of exposure. The major route of human exposure to methylmercury (MeHg is largely through eating contaminated fish, seafood, and wildlife which have been exposed to mercury through ingestion of contaminated lower organisms. MeHg toxicity is associated with nervous system damage in adults and impaired neurological development in infants and children. Ingested mercury may undergo bioaccumulation leading to progressive increases in body burdens. This review addresses the systemic pathophysiology of individual organ systems associated with mercury poisoning. Mercury has profound cellular, cardiovascular, hematological, pulmonary, renal, immunological, neurological, endocrine, reproductive, and embryonic toxicological effects.

  2. Soil contamination of toxic metals from zinc carbon batteries inadequate disposal

    International Nuclear Information System (INIS)

    Gazano, Vanessa Santos Oliveira

    2006-01-01

    The aim of the present study was to determine the concentration of Zn, Mn, Pb, Cd, Cu, Cr, and Ni in an oxisol column contaminated with zinc-carbon batteries. Two control and two contaminated columns, and batteries alone were leached for a periods of six months and one year with aqueous solution of HNO3 and H2SO4 (1:1, pH 4,0) to simulate rainwater. The metal concentrations in effluent and soil were measured by means of ICP-OES technique. Results from the contaminated column showed enhanced concentrations in both effluent and soil (mainly zinc, manganese and lead). In addition, the total amount of metals in effluent and soil showed similar sequence order as observed for batteries alone (Zn > Mn > Pb > Cr > Cu > Ni > Cd) indicating that batteries can be considered the main source of contamination. We also observed migration of Zn and Mn from the top to the lower layers of the soil columns. The study gives further evidence that batteries can significantly contaminate the soil with metals like Zn, Mn and Pb, and maybe Cd too. This soil contamination combined with the enhanced concentrations found in the effluent can point out a probable groundwater contamination. (author)

  3. Testing of toxicity based methods to develop site specific clean up objectives - phase 1: Toxicity protocol screening and applicability

    International Nuclear Information System (INIS)

    Hamilton, H.; Kerr, D.; Thorne, W.; Taylor, B.; Zadnik, M.; Goudey, S.; Birkholz, D.

    1994-03-01

    A study was conducted to develop a cost-effective and practical protocol for using bio-assay based toxicity assessment methods for remediation of decommissioned oil and gas production, and processing facilities. The objective was to generate site-specific remediation criteria for contaminated sites. Most companies have used the chemical-specific approach which, however, did not meet the ultimate land use goal of agricultural production. The toxicity assessment method described in this study dealt with potential impairment to agricultural crop production and natural ecosystems. Human health concerns were not specifically addressed. It was suggested that chemical-specific methods should be used when human health concerns exist. . Results showed that toxicity tests will more directly identify ecological stress caused by site contamination than chemical-specific remediation criteria, which can be unnecessarily protective. 11 refs., 7 tabs., 6 figs

  4. Effects of biochar and greenwaste compost amendments on mobility, bioavailability and toxicity of inorganic and organic contaminants in a multi-element polluted soil

    Energy Technology Data Exchange (ETDEWEB)

    Beesley, Luke, E-mail: L.Beesley@2007.ljmu.ac.u [Faculty of Science, Liverpool John Moores University, Liverpool L3 3AF (United Kingdom); Moreno-Jimenez, Eduardo [Departamento de Quimica Agricola, Universidad Autonoma de Madrid, 28049 Madrid (Spain); Gomez-Eyles, Jose L. [University of Reading, Department of Soil Science, Whiteknights, Reading RG6 6DW (United Kingdom)

    2010-06-15

    Applying amendments to multi-element contaminated soils can have contradictory effects on the mobility, bioavailability and toxicity of specific elements, depending on the amendment. Trace elements and PAHs were monitored in a contaminated soil amended with biochar and greenwaste compost over 60 days field exposure, after which phytotoxicity was assessed by a simple bio-indicator test. Copper and As concentrations in soil pore water increased more than 30 fold after adding both amendments, associated with significant increases in dissolved organic carbon and pH, whereas Zn and Cd significantly decreased. Biochar was most effective, resulting in a 10 fold decrease of Cd in pore water and a resultant reduction in phytotoxicity. Concentrations of PAHs were also reduced by biochar, with greater than 50% decreases of the heavier, more toxicologically relevant PAHs. The results highlight the potential of biochar for contaminated land remediation. - Biochar was more effective than greenwaste compost at reducing bioavailable fractions of phytotoxic Cd and Zn as well as the heavier, more toxicologically relevant PAHs.

  5. Development of a chronic sediment toxicity test for marine benthic amphipods

    International Nuclear Information System (INIS)

    DeWitt, T.H.; Redmond, M.S.; Sewall, J.E.; Swartz, R.C.

    1992-12-01

    The results of the research effort culminated in the development of a research method for assessing the chronic toxicity of contaminated marine and estuarine sediments using the benthic amphipod, Leptocheirus plumulosus. The first chapter describes the efforts at collecting, handling, and culturing four estuarine amphipods from Chesapeake Bay, including L. plumulosus. This chapter includes maps of the distribution and abundance of these amphipods within Chesapeake Bay and methodologies for establishing cultures of amphipods which could be readily adopted by other laboratories. The second chapter reports the development of acute and chronic sediment toxicity test methods for L. plumulosus, its sensitivity to non-contaminant environmental variables, cadmium, two polynuclear aromatic hydrocarbons, and contaminated sediment from Baltimore Harbor, MD. The third chapter reports the authors attempts to develop a chronic sediment toxicity test with Ampelisca abdita

  6. Characterization and remediation of a mixed waste-contaminated site at Kirtland Air Force Base, New Mexico

    International Nuclear Information System (INIS)

    Johnston, J.W.; Thacker, M.S.; DeWitt, C.B.

    1997-01-01

    In the area of environmental restoration, one of the most challenging problems is the task of remediating mixed waste-contaminated sites. This paper discusses a successful Interim Corrective Measure (ICM) performed at a mixed waste-contaminated site on Kirtland Air Force Base (AFB) in Albuquerque, New Mexico. The site, known as RW-68, Cratering Area and Radium Dump/Slag Piles, was used during the late 1940s and early 1950s for the destruction and incineration of captured World War II aircraft. It contained 19 slag piles totaling approximately 150 tons of slag, ash, refractory brick, and metal debris. The piles were contaminated with radium-226 and RCRA-characteristic levels of heavy metals. Therefore, the piles were considered mixed waste. To eliminate the threat to human health and the environment, an ICM of removal, segregation, stabilization, and disposal was conducted from October through December 1996. Approximately 120 cubic yards (cu yds) of mixed waste, 188 cu yds of low-level radioactive-contaminated soil, 1 cu yd of low-level radioactive-contaminated debris, 5 cu yds of RCRA-characteristic hazardous waste, and 45 tons of nonhazardous debris were stabilized and disposed of during the ICM. To render the RCRA metals and radionuclides insoluble, stabilization was performed on the mixed and RCRA-characteristic waste streams. All stabilized material was subjected to TCLP analysis to verify it no longer exhibited RCRA-characteristic properties. Radiological and geophysical surveys were conducted concurrently with site remediation activities. These surveys provided real-time documentation of site conditions during each phase of the ICM and confirmed successful cleanup of the site. The three radioactive waste streams, stabilized mixed waste, low-level radioactive-contaminated soil, and low-level radioactive-contaminated debris, were disposed of at the Envirocare low-level radioactive disposal facility

  7. Phytoremediation of soils and water contaminated with toxic elements and radionuclides

    International Nuclear Information System (INIS)

    Cornish, J.E.; Huddleston, G.J.; Levine, R.S.

    1995-01-01

    At many U.S. Department of Energy (DOE) facilities and other sites, large volumes of soils, sediments and waters are contaminated with heavy metals and/or radionuclides, often at only a relatively small factor above regulatory action levels. In response, the DOE's Office of Technology Development is evaluating the emerging biotechnology known as phytoremediation; this approach utilizes the accelerated transfer of contaminant mass from solution to either root or above ground biomass. After growth, the plant biomass - containing 100 to 1,000 times the contaminant levels observed with conventional plants - is processed to achieve further volume reduction and contaminant concentration. Thus, phytoremediation offers the potential for low cost remediation of highly to moderately contaminated media. Progress made to date by DOE in developing this technology will be summarized and evaluated

  8. Fisk-based criteria to support validation of detection methods for drinking water and air.

    Energy Technology Data Exchange (ETDEWEB)

    MacDonell, M.; Bhattacharyya, M.; Finster, M.; Williams, M.; Picel, K.; Chang, Y.-S.; Peterson, J.; Adeshina, F.; Sonich-Mullin, C.; Environmental Science Division; EPA

    2009-02-18

    This report was prepared to support the validation of analytical methods for threat contaminants under the U.S. Environmental Protection Agency (EPA) National Homeland Security Research Center (NHSRC) program. It is designed to serve as a resource for certain applications of benchmark and fate information for homeland security threat contaminants. The report identifies risk-based criteria from existing health benchmarks for drinking water and air for potential use as validation targets. The focus is on benchmarks for chronic public exposures. The priority sources are standard EPA concentration limits for drinking water and air, along with oral and inhalation toxicity values. Many contaminants identified as homeland security threats to drinking water or air would convert to other chemicals within minutes to hours of being released. For this reason, a fate analysis has been performed to identify potential transformation products and removal half-lives in air and water so appropriate forms can be targeted for detection over time. The risk-based criteria presented in this report to frame method validation are expected to be lower than actual operational targets based on realistic exposures following a release. Note that many target criteria provided in this report are taken from available benchmarks without assessing the underlying toxicological details. That is, although the relevance of the chemical form and analogues are evaluated, the toxicological interpretations and extrapolations conducted by the authoring organizations are not. It is also important to emphasize that such targets in the current analysis are not health-based advisory levels to guide homeland security responses. This integrated evaluation of chronic public benchmarks and contaminant fate has identified more than 200 risk-based criteria as method validation targets across numerous contaminants and fate products in drinking water and air combined. The gap in directly applicable values is

  9. Concentrations of chromium, manganese, and lead in air and in avian eggs

    International Nuclear Information System (INIS)

    Hui, C.A.

    2002-01-01

    Embryo exposure was not directly related to tropospheric levels of chromium, manganese or lead. - The expansion of urbanization introduces air pollution to wildlife areas. Some metal contaminants occurring in concentrations too small to have any measurable impact on adult birds may seriously affect embryos that are more sensitive to contaminants than the adult. Chromium, manganese, and lead are toxic and can be passed from the hen to the egg. This study relates the concentrations of these metals in eggs to their concentrations in air in three cities. Rock dove eggs were sampled and air pollution records were examined in the California cities of Riverside, Los Angeles, and San Francisco. The eggs from San Francisco did not differ from those of Los Angeles in lead concentration but the air did differ. The eggs collected in Los Angeles in 1998 had concentrations of chromium greater than in those from Riverside and from Los Angeles 1999 but the air had concentrations of chromium that did not differ among those three collections. Concentrations of manganese did not differ among the eggs but did differ among the air samples of the three cities. Exposures of embryos to chromium and manganese in this study were not at levels warranting concern. Although the concentration at which lead in eggs impairs avian health is not established, the highest concentrations found in this study exceed estimated safe concentrations. There is no indication that embryo exposure is directly related to atmospheric levels of these metals in the cities of this study

  10. Heavy metal-immobilizing organoclay facilitates polycyclic aromatic hydrocarbon biodegradation in mixed-contaminated soil

    International Nuclear Information System (INIS)

    Biswas, Bhabananda; Sarkar, Binoy; Mandal, Asit; Naidu, Ravi

    2015-01-01

    Highlights: • A novel metal-immobilizing organoclay (MIOC) synthesized and characterized. • MIOC immobilizes toxic metals and reduces metal bioavailability. • It enhances PAH-bioavailability to soil bacteria. • It improves microbial growth and activities in mixed-contaminated soils. • MIOC facilitates PAH-biodegradation in metal co-contaminated soils. - Abstract: Soils contaminated with a mixture of heavy metals and polycyclic aromatic hydrocarbons (PAHs) pose toxic metal stress to native PAH-degrading microorganisms. Adsorbents such as clay and modified clay minerals can bind the metal and reduce its toxicity to microorganisms. However, in a mixed-contaminated soil, an adsorption process more specific to the metals without affecting the bioavailability of PAHs is desired for effective degradation. Furthermore, the adsorbent should enhance the viability of PAH-degrading microorganisms. A metal-immobilizing organoclay (Arquad ® 2HT-75-bentonite treated with palmitic acid) (MIOC) able to reduce metal (cadmium (Cd)) toxicity and enhance PAH (phenanthrene) biodegradation was developed and characterized in this study. The MIOC differed considerably from the parent clay in terms of its ability to reduce metal toxicity (MIOC > unmodified bentonite > Arquad–bentonite). The MIOC variably increased the microbial count (10–43%) as well as activities (respiration 3–44%; enzymatic activities up to 68%), and simultaneously maintained phenanthrene in bioavailable form in a Cd-phenanthrene mixed-contaminated soil over a 21-day incubation period. This study may lead to a new MIOC-assisted bioremediation technique for PAHs in mixed-contaminated soils

  11. Heavy metal-immobilizing organoclay facilitates polycyclic aromatic hydrocarbon biodegradation in mixed-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Bhabananda; Sarkar, Binoy [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, P.O. Box 486, Salisbury, SA 5106 (Australia); Mandal, Asit [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia); Division of Soil Biology, Indian Institute of Soil Science, Bhopal, Madhya Pradesh (India); Naidu, Ravi [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, P.O. Box 486, Salisbury, SA 5106 (Australia)

    2015-11-15

    Highlights: • A novel metal-immobilizing organoclay (MIOC) synthesized and characterized. • MIOC immobilizes toxic metals and reduces metal bioavailability. • It enhances PAH-bioavailability to soil bacteria. • It improves microbial growth and activities in mixed-contaminated soils. • MIOC facilitates PAH-biodegradation in metal co-contaminated soils. - Abstract: Soils contaminated with a mixture of heavy metals and polycyclic aromatic hydrocarbons (PAHs) pose toxic metal stress to native PAH-degrading microorganisms. Adsorbents such as clay and modified clay minerals can bind the metal and reduce its toxicity to microorganisms. However, in a mixed-contaminated soil, an adsorption process more specific to the metals without affecting the bioavailability of PAHs is desired for effective degradation. Furthermore, the adsorbent should enhance the viability of PAH-degrading microorganisms. A metal-immobilizing organoclay (Arquad{sup ®} 2HT-75-bentonite treated with palmitic acid) (MIOC) able to reduce metal (cadmium (Cd)) toxicity and enhance PAH (phenanthrene) biodegradation was developed and characterized in this study. The MIOC differed considerably from the parent clay in terms of its ability to reduce metal toxicity (MIOC > unmodified bentonite > Arquad–bentonite). The MIOC variably increased the microbial count (10–43%) as well as activities (respiration 3–44%; enzymatic activities up to 68%), and simultaneously maintained phenanthrene in bioavailable form in a Cd-phenanthrene mixed-contaminated soil over a 21-day incubation period. This study may lead to a new MIOC-assisted bioremediation technique for PAHs in mixed-contaminated soils.

  12. TOXIC LEADERSHIP: A SYSTEMIC APPROACH TO SHIFT FROM REACTIVE TO PROACTIVE SOLUTIONS

    Science.gov (United States)

    2017-03-01

    AIR COMMAND AND STAFF COLLEGE AIR UNIVERSITY TOXIC LEADERSHIP: A SYSTEMIC APPROACH TO SHIFT FROM REACTIVE TO PROACTIVE SOLUTIONS...DISTRIBUTION A. Approved for public release: distribution unlimited. Toxic Leadership: A Systemic Approach to Shift From Reactive to Proactive Solutions 1...US military loses valuable personnel when it is too late to implement corrective action and after those toxic Toxic Leadership: A Systemic Approach

  13. Indoor air pollution

    International Nuclear Information System (INIS)

    Spengler, J.D.

    1985-01-01

    Although official efforts to control air pollution have traditionally focused on outdoor air, it is now apparent that elevated contaminant concentrations are common inside some private and public buildings. Concerns about potential public health problems due to indoor air pollution are based on evidence that urban residents typically spend more than 90 percent of their time indoors, concentrations of some contaminants are higher indoors than outdoors, and for some pollutants personal exposures are not characterized adequately by outdoor measurements. Among the more important indoor contaminants associated with health or irritation effects are passive tobacco smoke, radon decay products, carbon monoxide, nitrogen dioxide, formaldehyde, asbestos fibers, microorganisms and aeroallergens. Efforts to assess health risks associated with indoor air pollution are limited by insufficient information about the number of people exposed, the pattern and severity of exposures, and the health consequences of exposures. An overall strategy should be developed to investigate indoor exposures, health effects, control options, and public policy alternatives

  14. Measurement of radioactive soil contamination from the air

    International Nuclear Information System (INIS)

    Loman, A.C.; Kuile, C.R. ter; Slaper, H.

    1990-09-01

    In-situ gamma spectrometry can be used to determine the qualitative and quantitative deposition of radioactive materials on the ground surface. By applying the in-situ spectrometry method using either a helicopter or an airplane, large areas can be scanned in a short period of time. In this report the results of in-situ gamma spectroscopic measurements taken from a helicopter are described. Measurements were carried out using a single point source, a field of 36 point sources, and using the present ground contamination due to fall-out from the Chernobyl accident and atom bombs. The results of these measurements were used to determine calibration factors, which were in agreement with a calibration obtained using more simple (and less expensive) laboratory measurements in combination with flux calculations. Detection limits for the measurement of surface contamination were determined. At a height of 50 meters above the surface and using a measurement time of 2 minutes, the minimally detectable surface contamination was 1.1 kBqm -2 for a Cs-137 contamination and 2.1 kBqm -2 for I-131 contamination. Fall-out determinations based on measurements taken at a height of 50 meters were in agreement with determinations taken at a height of 1 meter, and with the results obtained measuring soil samples. The in-situ gamma spectroscopy, using helicopter or airplane, is a fast and powerful method for mapping surface contamination. (author). 13 refs.; 18 figs.; 13 tabs

  15. Fungal contamination in hospital environments.

    Science.gov (United States)

    Perdelli, F; Cristina, M L; Sartini, M; Spagnolo, A M; Dallera, M; Ottria, G; Lombardi, R; Grimaldi, M; Orlando, P

    2006-01-01

    To assess the degree of fungal contamination in hospital environments and to evaluate the ability of air conditioning systems to reduce such contamination. We monitored airborne microbial concentrations in various environments in 10 hospitals equipped with air conditioning. Sampling was performed with a portable Surface Air System impactor with replicate organism detection and counting plates containing a fungus-selective medium. The total fungal concentration was determined 72-120 hours after sampling. The genera most involved in infection were identified by macroscopic and microscopic observation. The mean concentration of airborne fungi in the set of environments examined was 19 +/- 19 colony-forming units (cfu) per cubic meter. Analysis of the fungal concentration in the different types of environments revealed different levels of contamination: the lowest mean values (12 +/- 14 cfu/m(3)) were recorded in operating theaters, and the highest (45 +/- 37 cfu/m(3)) were recorded in kitchens. Analyses revealed statistically significant differences between median values for the various environments. The fungal genus most commonly encountered was Penicillium, which, in kitchens, displayed the highest mean airborne concentration (8 +/- 2.4 cfu/m(3)). The percentage (35%) of Aspergillus documented in the wards was higher than that in any of the other environments monitored. The fungal concentrations recorded in the present study are comparable to those recorded in other studies conducted in hospital environments and are considerably lower than those seen in other indoor environments that are not air conditioned. These findings demonstrate the effectiveness of air-handling systems in reducing fungal contamination.

  16. Radiation protection at the RA Reactor in 1985, Part -2, Annex 2b, Environmental Radioactivity control, Control of air contamination

    International Nuclear Information System (INIS)

    Patic, D.; Smiljanic, R.; Zaric, M.; Savic, Z.; Ristic, D.

    1985-01-01

    During the period from November 1984 - November 1985, within the radioactivity control on the Vinca Institute site air contamination radioactive aerosol contents was measured. Control was done on 4 measuring stations, two in the Institute and two locations in the direction of wind i.e. Belgrade, 2 km and 7 km away from the Institute respectively. This position of the measuring locations enables control of radiation safety of the Institute, as well as environment of Belgrade taking into account the existence of the reactor and other possible contaminants in the Institute [sr

  17. REAL-TIME EMISSION CHARACTERIZATION OF ORGANIC AIR TOXIC POLLUTANTS DURING STEADY STATE AND TRANSIENT OPERATION OF A MEDIUM DUTY DIESEL ENGINE

    Science.gov (United States)

    An on-line monitoring method, jet resonance-enhanced multi-photon ionization (REMPI) with time-of-flight mass spectrometry (TOFMS) was used to measure emissions of organic air toxics from a medium-duty (60 kW)diesel generator during transient and steady state operations. Emission...

  18. Air Filtration as Protection against Fouling of Ventilation and Air Conditioning Units

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Lajčíková, Ariana

    2005-01-01

    Currently, air filters are one of the most critical components of air treatment systems as they decontaminate the air delivered to living space. During the operation, however, the level of harmful surface deposits increases, and at certain times, an uncleaned filter can itself become a source...... of undesirable contaminents influencing negatively the IAQ of a living space. This is the phenomenon that has been a subject of the current research. The article presents a new, alternative view on indoor air contaminents and filtration requirements. It describes alternative means of filtration and assesses...... issues of inadequate maintenance and/or long term use of applied air filters. An experimental method of evealuating the air quality by means of chemical analysis and state-of-the-art spectrometer is also described....

  19. 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. © 2013.

  20. Volatile organic compounds in indoor air: A review ofconcentrations measured in North America since 1990

    Energy Technology Data Exchange (ETDEWEB)

    ATHodgson@lbl.gov

    2003-04-01

    Central tendency and upper limit concentrations of volatile organic compounds (VOCs) measured in indoor air are summarized and reviewed. Data were obtained from published cross-sectional studies of residential and office buildings conducted in North America from 1990through the present. VOC concentrations in existing residences reported in 12 studies comprise the majority of the data set. Central tendency and maximum concentrations are compared between new and existing residences and between existing residences and office buildings. Historical changes in indoor VOC concentrations since the Clean Air Act Amendments of 1990 are explored by comparing the current data set with two published reviews of previous data obtained primarily in the 1980s. These historical comparisons suggest average indoor concentrations of some toxic air contaminants, such as 1,1,1-trichloroethane have decreased.