Temporal variability of selected air toxics in the United States

NASA Astrophysics Data System (ADS)

McCarthy, Michael C.; Hafner, Hilary R.; Chinkin, Lyle R.; Charrier, Jessica G.

Ambient measurements of hazardous air pollutants (HAPs, air toxics) collected in the United States from 1990 to 2005 were analyzed for diurnal, seasonal, and/or annual variability and trends. Visual and statistical analyses were used to identify and quantify temporal variations in air toxics at national and regional levels. Sufficient data were available to analyze diurnal variability for 14 air toxics, seasonal variability for 24 air toxics, and annual trends for 26 air toxics. Four diurnal variation patterns were identified and labeled invariant, nighttime peak, morning peak, and daytime peak. Three distinct seasonal patterns were identified and labeled invariant, cool, and warm. Multiple air toxics showed consistent decreasing trends over three trend periods, 1990-2005, 1995-2005, and 2000-2005. Trends appeared to be relatively consistent within chemically similar pollutant groups. Hydrocarbons such as benzene, 1,3-butadiene, styrene, xylene, and toluene decreased by approximately 5% or more per year at more than half of all monitoring sites. Concentrations of carbonyl compounds such as formaldehyde, acetaldehyde, and propionaldehyde were equally likely to have increased or decreased at monitoring sites. Chlorinated volatile organic compounds (VOCs) such as tetrachloroethylene, dichloromethane, and methyl chloroform decreased at more than half of all monitoring sites, but decreases among these species were much more variable than among the hydrocarbons. Lead particles decreased in concentration at most monitoring sites, but trends in other metals were not consistent over time.

AIR TOXICS MODELING RESEARCH PROGRAM: AN OVERVIEW

EPA Science Inventory

This product is a Microsoft Powerpoint slide presentation which was given at the joint EPA Region 3 - Mid-Atlantic Regional Air Management Association (MARAMA) Air Toxic Summit in Philadelphia, Pennsylvania held from October 18, 2005 through October 20, 2005. The slide presentat...

Air quality modeling of selected aromatic and non-aromatic air toxics in the Houston urban and industrial airshed

NASA Astrophysics Data System (ADS)

Coarfa, Violeta Florentina

2007-12-01

Air toxics, also called hazardous air pollutants (HAPs), pose a serious threat to human health and the environment. Their study is important in the Houston area, where point sources, mostly located along the Ship Channel, mobile and area sources contribute to large emissions of such toxic pollutants. Previous studies carried out in this area found dangerous levels of different HAPs in the atmosphere. This thesis presents several studies that were performed for the aromatic and non-aromatic air toxics in the HGA. For these studies we developed several tools: (1) a refined chemical mechanism, which explicitly represents 18 aromatic air toxics that were lumped under two model species by the previous version, based on their reactivity with the hydroxyl radical; (2) an engineering version of an existing air toxics photochemical model that enables us to perform much faster long-term simulations compared to the original model, that leads to a 8--9 times improvement in the running time across different computing platforms; (3) a combined emission inventory based on the available emission databases. Using the developed tools, we quantified the mobile source impact on a few selected air toxics, and analyzed the temporal and spatial variation of selected aromatic and non-aromatic air toxics in a few regions within the Houston area; these regions were characterized by different emissions and environmental conditions.

Basic Information about Mercury and Air Toxics Standards

EPA Pesticide Factsheets

The U.S. Environmental Protection Agency (EPA) has proposed Mercury and Air Toxics Standards (MATS) for power plants to limit mercury, acid gases and other toxic pollution from power plants. This page describes how federal mercury standards work.

Mobile source air toxics mitigation measures.

DOT National Transportation Integrated Search

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...

DEVELOPMENT AND VALIDATION OF AN AIR-TO-BEEF ...

EPA Pesticide Factsheets

A model for predicting concentrations of dioxin-like compounds in beef is developed and tested. The key premise of the model is that concentrations of these compounds in air are the source term, or starting point, for estimating beef concentrations. Vapor-phase concentrations transfer to vegetations cattle consume, and particle-bound concentrations deposit onto soils and these vegetations as well. Congener-specific bioconcentration parameters, coupled with assumptions on cattle diet, transform soil and vegetative concentrations into beef fat concentrations. The premise of the validation exercise is that a profile of typical air concentrations of dioxin-like compounds in a United States rural environment is an appropriate observed independent data set, and that a representative profile of United States beef concentrations of dioxin-like compounds is an appropriate observed dependent result. These data were developed for the validation exercise. An observed concentration of dioxin toxic equivalents in whole beef of 0.48 ng/kg is compared with a predicted 0.36 ng/kg. Principal uncertainties in the approach are identified and discussed. A major finding of this exercise was that vapor phase transfers of dioxin-like compounds to vegetations that cattle consume dominate the estimation of final beef concentrations: over 80% of the modeled beef concentration was attributed to such transfers. journal article

Do 16 Polycyclic Aromatic Hydrocarbons Represent PAH Air Toxicity?

PubMed Central

Samburova, Vera; Zielinska, Barbara; Khlystov, Andrey

2017-01-01

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 (∑88BaPeq) of gas- and particle-phase PAHs were compared with BaPeq toxicities calculated for the 16 particle-phase EPA PAH (∑16EPABaPeq). 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 ∑88BaPeq. 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. PMID:29051449

Do 16 Polycyclic Aromatic Hydrocarbons Represent PAH Air Toxicity?

PubMed

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.

Temporal and modal characterization of DoD source air toxic ...

EPA Pesticide Factsheets

This project tested three, real-/near real-time monitoring techniques to develop air toxic emission factors for Department of Defense (DoD) platform sources. These techniques included: resonance enhanced multi photon ionization time of flight mass spectrometry (REMPI-TOFMS) for organic air toxics, laser induced breakdown spectroscopy (LIBS) for metallic air toxics, and optical remote sensing (ORS) methods for measurement of criteria pollutants and other hazardous air pollutants (HAPs). Conventional emission measurements were used for verification of the real-time monitoring results. The REMPI-TOFMS system was demonstrated on the following: --a United States U.S. Marine Corps (USMC) diesel generator, --a U.S. Air Force auxiliary power unit (APU), --the waste combustor at the Portsmouth Naval Shipyard, during a multi-monitor environmental technology verification (ETV) test for dioxin monitoring systems, --two dynamometer-driven high mobility multi-purpose wheeled vehicles (HMMWVs), --an idling Abrams battle tank, --a Bradley infantry fighting vehicle (IFV), and --an F-15 and multiple F-22 U.S. Air Force aircraft engines. LIBS was tested and applied solely to the U.S. Marine Corps diesel generator. The high detection limits of LIBS for toxic metals limited its usefulness as a real time analyzer for most DoD sources. ORS was tested only on the APU with satisfactory results for non-condensable combustion products (carbon monoxide [CO], carbon dioxide

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 implicationsmore » 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.« less

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 implicationsmore » 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.« less

EMISSIONS OF ORGANIC AIR TOXICS FROM OPEN BURNING: A COMPREHENSIVE REVIEW

EPA Science Inventory

A detailed literature search was performed to collect and collate available data reporting emissions of organic air toxics from open burning sources. Availability of data varied according to the source and the class of air toxics of interest, and there were several sources for wh...

AIR TOXICS EMISSIONS FROM ELECTRONICS INCINERATION

EPA Science Inventory

The purpose of this project is to examine the emissions of air toxics from the combustion of electronics equipment, primarily personal computer components. Due to a shortage of recycling programs for personal computers and other personal electronics equipment, most of these mate...

AIR QUALITY MODELING OF PM AND AIR TOXICS AT NEIGHBORHOOD SCALES

EPA Science Inventory

The current interest in fine particles and toxics pollutants provide an impetus for extending air quality modeling capability towards improving exposure modeling and assessments. Human exposure models require information on concentration derived from interpolation of observati...

Retinoblastoma and ambient exposure to air toxics in the perinatal period

PubMed Central

Heck, Julia E.; Park, Andrew S.; Qiu, Jiaheng; Cockburn, Myles; Ritz, Beate

2014-01-01

We examined ambient exposure to specific air toxics in the perinatal period in relation to retinoblastoma development. Cases were ascertained from California Cancer Registry records of children diagnosed 1990–2007 and matched to California birth certificates. Controls were randomly selected from state birth records for the same time period. We chose 27 air toxics for the present study that had been listed as possible, probable, or established human carcinogens by the International Agency for Research on Cancer. Children (103 cases and 30,601 controls) included in the study lived within 5 miles (~8K) of an air pollution monitor. Using logistic regression analyses, we modeled the risk of retinoblastoma due to air toxics exposure, separately for exposures in pregnancy and the first year of life. With a per interquartile range increase in air toxics exposure, retinoblastoma risk was found to be increased with pregnancy exposure to benzene (OR=1.67, 95%CI 1.06, 2.64) and other toxics which primarily arise from gasoline and diesel combustion: toluene, 1,3 butadiene, ethyl benzene, ortho-xylene, and meta/para-xylene; these 6 toxics were highly correlated. Retinoblastoma risk was also increased with pregnancy exposure to chloroform (OR=1.35, 95%CI 1.07, 1.70), chromium (OR=1.29, 95%CI 1.04, 1.60), para-dichlorobenzene (OR=1.24, 95%CI 1.04, 1.49), nickel (OR=1.48, 95%CI 1.08, 2.01), and in the first year of life, acetaldehyde (OR=1.62, 95%CI 1.06, 2.48). Sources of these agents are discussed. PMID:24280682

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

PubMed

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.

In Utero Exposure to Toxic Air Pollutants and Risk of Childhood Autism

PubMed Central

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

2015-01-01

Background 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. Methods Among the cohort of children born in Los Angeles County, California 1995–2006, those whose mothers resided during pregnancy in a 5km 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. Results Autism risks were increased per interquartile-range increase in average concentrations during pregnancy of several correlated toxics mostly loading on one factor, including 1,3-butadiene (OR=1.59 [95% confidence interval=1.18–2.15]), meta/para-xylene (1.51 [1.26–182]), 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, maternal birth place, parity, child sex, and birth year. Conclusions 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. PMID:25051312

News focus: Report on state and local air toxics regulatory strategies published by STAPPA/ALAPCO (State and Territorial Air Pollution Program Administrators/Association of Local Air Pollution Control Officials)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1989-12-01

The report is entitled Toxic Air Pollutants: State and Local Regulatory Strategies - 1989. The 364-page report is the result of a survey of state and local air pollution control agencies, which solicited information on their programs to control air toxics. According to the survey, every state currently has a program to address emissions of air toxics. Additionally, 27 of the 40 local agencies that responded to the survey have, or are developing, air toxics programs. The strategies employed by state and local agencies vary widely, including control technology requirements, risk assessment, acceptable ambient guidelines, or a combination of thesemore » approaches. This is a report summarizing the air toxics control programs currently implemented (or under development) by state and local air pollution control agencies throughout the US. The report is based upon a survey of all 50 states and 220 local air pollution control agencies conducted by the State and Territorial Air Pollution Program Administrators (STAPPA) and the Association of Local Air Pollution Control Officials (ALAPCO). This survey updates one published five years earlier.« less

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

PubMed

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

Uneven Magnitude of Disparities in Cancer Risks from Air Toxics

PubMed Central

James, Wesley; Jia, Chunrong; Kedia, Satish

2012-01-01

This study examines race- and income-based disparities in cancer risks from air toxics in Cancer Alley, LA, USA. Risk estimates were obtained from the 2005 National Air Toxics Assessment and socioeconomic and race data from the 2005 American Community Survey, both at the census tract level. Disparities were assessed using spatially weighted ordinary least squares (OLS) regression and quantile regression (QR) for five major air toxics, each with cancer risk greater than 10−6. Spatial OLS results showed that disparities in cancer risks were significant: People in low-income tracts bore a cumulative risk 12% more than those in high-income tracts (p < 0.05), and those in black-dominant areas 16% more than in white-dominant areas (p < 0.01). Formaldehyde and benzene were the two largest contributors to the disparities. Contributions from emission sources to disparities varied by compound. Spatial QR analyses showed that magnitude of disparity became larger at the high end of exposure range, indicating worsened disparity in the poorest and most highly concentrated black areas. Cancer risk of air toxics not only disproportionately affects socioeconomically disadvantaged and racial minority communities, but there is a gradient effect within these groups with poorer and higher minority concentrated segments being more affected than their counterparts. Risk reduction strategies should target emission sources, risk driver chemicals, and especially the disadvantaged neighborhoods. PMID:23208297

The National Near-Road Mobile Source Air Toxics Study

EPA Science Inventory

Recently, much attention has been directed at understanding the impact of mobile sources on near-road air quality, especially PM and its components, NOx and CO, but little information exists for mobile source air toxics (MSATs). MSATs of interest to this project are 1,3-butadiene...

Emission factors of air toxics from semiconductor manufacturing in Korea.

PubMed

Eom, Yun-Sung; Hong, Ji-Hyung; Lee, Suk-Jo; Lee, Eun-Jung; Cha, Jun-Seok; Lee, Dae-Gyun; Bang, Sun-Ae

2006-11-01

The development of local, accurate emission factors is very important for the estimation of reliable national emissions and air quality management. For that, this study is performed for pollutants released to the atmosphere with source-specific emission tests from the semiconductor manufacturing industry. The semiconductor manufacturing industry is one of the major sources of air toxics or hazardous air pollutants (HAPs); thus, understanding the emission characteristics of the emission source is a very important factor in the development of a control strategy. However, in Korea, there is a general lack of information available on air emissions from the semiconductor industry. The major emission sources of air toxics examined from the semiconductor manufacturing industry were wet chemical stations, coating applications, gaseous operations, photolithography, and miscellaneous devices in the wafer fabrication and semiconductor packaging processes. In this study, analyses of emission characteristics, and the estimations of emission data and factors for air toxics, such as acids, bases, heavy metals, and volatile organic compounds from the semiconductor manufacturing process have been performed. The concentration of hydrogen chloride from the packaging process was the highest among all of the processes. In addition, the emission factor of total volatile organic compounds (TVOCs) for the packaging process was higher than that of the wafer fabrication process. Emission factors estimated in this study were compared with those of Taiwan for evaluation, and they were found to be of similar level in the case of TVOCs and fluorine compounds.

CMAQ MODELING FOR AIR TOXICS AT FINE SCALES: A PROTOTYPE STUDY

EPA Science Inventory

Toxic air pollutants (TAPs) or hazardous air pollutants (HAPs) exhibit considerable spatial and temporal variability across urban areas. Therefore, the ability of chemical transport models (CTMs), e.g. Community Multi-scale Air Quality (CMAQ), to reproduce the spatial and tempor...

National review of ambient air toxics observations.

PubMed

Strum, Madeleine; Scheffe, Richard

2016-02-01

Ambient air observations of hazardous air pollutant (HAPs), also known as air toxics, derived from routine monitoring networks operated by states, local agencies, and tribes (SLTs), are analyzed to characterize national concentrations and risk across the nation for a representative subset of the 187 designated HAPs. Observations from the National Air Toxics Trend Sites (NATTS) network of 27 stations located in most major urban areas of the contiguous United States have provided a consistent record of HAPs that have been identified as posing the greatest risk since 2003 and have also captured similar concentration patterns of nearly 300 sites operated by SLTs. Relatively high concentration volatile organic compounds (VOCs) such as benzene, formaldehyde, and toluene exhibit the highest annual average concentration levels, typically ranging from 1 to 5 µg/m(3). Halogenated (except for methylene chloride) and semivolatile organic compounds (SVOCs) and metals exhibit concentrations typically 2-3 orders of magnitude lower. Formaldehyde is the highest national risk driver based on estimated cancer risk and, nationally, has not exhibited significant changes in concentration, likely associated with the large pool of natural isoprene and formaldehyde emissions. Benzene, toluene, ethylbenzene, and 1,3-butadiene are ubiquitous VOC HAPs with large mobile source contributions that continue to exhibit declining concentrations over the last decade. Common chlorinated organic compounds such as ethylene dichloride and methylene chloride exhibit increasing concentrations. The variety of physical and chemical attributes and measurement technologies across 187 HAPs result in a broad range of method detection limits (MDLs) and cancer risk thresholds that challenge confidence in risk results for low concentration HAPs with MDLs near or greater than risk thresholds. From a national monitoring network perspective, the ability of the HAPs observational database to characterize the multiple

Exposures to multiple air toxics in New York City.

PubMed Central

Kinney, Patrick L; Chillrud, Steven N; Ramstrom, Sonja; Ross, James; Spengler, John D

2002-01-01

Efforts to assess health risks associated with exposures to multiple urban air toxics have been hampered by the lack of exposure data for people living in urban areas. The TEACH (Toxic Exposure Assessment, a Columbia/Harvard) study was designed to characterize levels of and factors influencing personal exposures to urban air toxics among high school students living in inner-city neighborhoods of New York City and Los Angeles, California. This present article reports methods and data for the New York City phase of TEACH, focusing on the relationships between personal, indoor, and outdoor concentrations in winter and summer among a group of 46 high school students from the A. Philip Randolph Academy, a public high school located in the West Central Harlem section of New York City. Air pollutants monitored included a suite of 17 volatile organic compounds (VOCs) and aldehydes, particulate matter with a mass median aerodynamic diameter air exchange rates. For other VOCs, especially those related to motor vehicle exhaust, more consistent indoor, outdoor, and personal concentrations were observed, suggesting that ambient concentrations may have been the

Exposures to multiple air toxics in New York City.

PubMed

Kinney, Patrick L; Chillrud, Steven N; Ramstrom, Sonja; Ross, James; Spengler, John D

2002-08-01

Efforts to assess health risks associated with exposures to multiple urban air toxics have been hampered by the lack of exposure data for people living in urban areas. The TEACH (Toxic Exposure Assessment, a Columbia/Harvard) study was designed to characterize levels of and factors influencing personal exposures to urban air toxics among high school students living in inner-city neighborhoods of New York City and Los Angeles, California. This present article reports methods and data for the New York City phase of TEACH, focusing on the relationships between personal, indoor, and outdoor concentrations in winter and summer among a group of 46 high school students from the A. Philip Randolph Academy, a public high school located in the West Central Harlem section of New York City. Air pollutants monitored included a suite of 17 volatile organic compounds (VOCs) and aldehydes, particulate matter with a mass median aerodynamic diameter air exchange rates. For other VOCs, especially those related to motor vehicle exhaust, more consistent indoor, outdoor, and personal concentrations were observed, suggesting that ambient concentrations may have been the

Respiratory tract toxicity in rats exposed to Mexico City air.

PubMed

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

Toxicity of Silver Nanoparticles at the Air-Liquid Interface

PubMed Central

Holder, Amara L.; Marr, Linsey C.

2013-01-01

Silver nanoparticles are one of the most prevalent nanomaterials in consumer products. Some of these products are likely to be aerosolized, making silver nanoparticles a high priority for inhalation toxicity assessment. To study the inhalation toxicity of silver nanoparticles, we have exposed cultured lung cells to them at the air-liquid interface. Cells were exposed to suspensions of silver or nickel oxide (positive control) nanoparticles at concentrations of 2.6, 6.6, and 13.2 μg cm−2 (volume concentrations of 10, 25, and 50 μg ml−1) and to 0.7 μg cm−2 silver or 2.1 μg cm−2 nickel oxide aerosol at the air-liquid interface. Unlike a number of in vitro studies employing suspensions of silver nanoparticles, which have shown strong toxic effects, both suspensions and aerosolized nanoparticles caused negligible cytotoxicity and only a mild inflammatory response, in agreement with animal exposures. Additionally, we have developed a novel method using a differential mobility analyzer to select aerosolized nanoparticles of a single diameter to assess the size-dependent toxicity of silver nanoparticles. PMID:23484109

Analysis of Mobile Source Air Toxics (MSATS)–Near-Road VOC and CarbonylConcentrations

EPA Science Inventory

This presentation examines data from a year-long study of measured near-road mobile source air toxic (MSAT) concentrations and compares these data with modeled 2005 National Air Toxic Assessment (NATA) results. Field study measurements were collected during a field campaign in ...

Analysis of mobile source air toxics (MSATs)–Near-Road VOC and carbonyl concentrations

EPA Science Inventory

Exposures to mobile source air toxics (MSATs) have been associated with numerous adverse health effects. While thousands of air toxic compounds are emitted from mobile sources, a subset of compounds are considered high priority due to their significant contribution to cancer and...

Evaporation and air-stripping to assess and reduce ethanolamines toxicity in oily wastewater.

PubMed

Libralato, G; Ghirardini, A Volpi; Avezzù, F

2008-05-30

Toxicity from industrial oily wastewater remains a problem even after conventional activated sludge treatment process, because of the persistence of some toxicant compounds. This work verified the removal efficiency of organic and inorganic pollutants and the effects of evaporation and air-stripping techniques on oily wastewater toxicity reduction. In a lab-scale plant, a vacuum evaporation procedure at three different temperatures and an air-stripping stage were tested on oily wastewater. Toxicity reduction/removal was observed at each treatment step via Microtox bioassay. A case study monitoring real scale evaporation was also done in a full-size wastewater treatment plant (WWTP). To implement part of a general project of toxicity reduction evaluation, additional investigations took into account the monoethanolamine (MEA), diethanolamine (DEA) and triethanolamine (TEA) role in toxicity definition after the evaporation phase, both as pure substances and mixtures. Only MEA and TEA appeared to contribute towards effluent toxicity.

Reduced Toxicity, High Performance Monopropellant at the U.S. Air Force Research Laboratory

DTIC Science & Technology

2010-04-27

develop reduced toxicity monopropellant formulations to replace spacecraft hydrazine monopropellant. The Air Force Research Laboratory’s (AFRL’s...Public Release, Distribution unlimited REDUCED TOXICITY, HIGH PERFORMANCE MONOPROPELLANT AT THE U.S. AIR FORCE RESEARCH LABORATORY T.W. Hawkins...information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations

Evolution of the Air Toxics under the Big Sky Program

ERIC Educational Resources Information Center

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…

Laser photoacoustic sensor for air toxicity measurements

NASA Astrophysics Data System (ADS)

Prasad, Coorg R.; Lei, Jie; Shi, Wenhui; Li, Guangkun; Dunayevskiy, Ilya; Patel, C. Kumar N.

2012-06-01

US EPA's Clean Air Act lists 187 hazardous air pollutants (HAP) or airborne toxics that are considered especially harmful to health, and hence the measurement of their concentration is of great importance. Numerous sensor systems have been reported for measuring these toxic gases and vapors. However, most of these sensors are specific to a single gas or able to measure only a few of them. Thus a sensor capable of measuring many of the toxic gases simultaneously is desirable. Laser photoacoustic spectroscopy (LPAS) sensors have the potential for true broadband measurement when used in conjunction with one or more widely tunable laser sources. An LPAS gas analyzer equipped with a continuous wave, room temperature IR Quantum Cascade Laser tunable over the wavelength range of 9.4 μm to 9.7 μm was used for continuous real-time measurements of multiple gases/chemical components. An external cavity grating tuner was used to generate several (75) narrow line output wavelengths to conduct photoacoustic absorption measurements of gas mixtures. We have measured various HAPs such as Benzene, Formaldehyde, and Acetaldehyde in the presence of atmospheric interferents water vapor, and carbon dioxide. Using the preliminary spectral pattern recognition algorithm, we have shown our ability to measure all these chemical compounds simultaneously in under 3 minutes. Sensitivity levels of a few part-per-billion (ppb) were achieved with several of the measured compounds with the preliminary laboratory system.

Validation of Screening Assays for Developmental Toxicity: An Exposure-Based Approach

EPA Science Inventory

There continue to be widespread efforts to develop assay methods for developmental toxicity that are shorter than the traditional Segment 2 study and use fewer or no animals. As with any alternative test method, novel developmental toxicity assays must be validated by evaluating ...

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

NASA Astrophysics Data System (ADS)

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

[Toxic fungi in Buenos Aires City and surroundings].

PubMed

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.

Regulatory Actions - Final Mercury and Air Toxics Standards (MATS) for Power Plants

EPA Pesticide Factsheets

The U.S. Environmental Protection Agency (EPA) has proposed Mercury and Air Toxics Standards (MATS) for power plants to limit mercury, acid gases and other toxic pollution from power plants. This page describes Federal regulatory actions.

Regulatory Actions - Proposed Mercury and Air Toxics Standards (MATS) for Power Plants

EPA Pesticide Factsheets

The U.S. Environmental Protection Agency (EPA) has proposed Mercury and Air Toxics Standards (MATS) for power plants to limit mercury, acid gases and other toxic pollution from power plants. This page includes supporting documentation and

IDENTIFYING TOXIC LEADERSHIP BEHAVIORS AND TOOLS TO FACILITATE THEIR DISCOVERY

DTIC Science & Technology

2016-01-31

AIR WAR COLLEGE AIR UNIVERSITY IDENTIFYING TOXIC LEADERSHIP BEHAVIORS AND TOOLS TO FACILITATE THEIR DISCOVERY by Michael Boger, Lt Col...released investigations for specific, observable traits relating to toxic behavior . 3) Discuss indicators and concerns in steps one and two with...subordinates, which will aid in validating the specific observable behaviors from the lenses of each of these positions. The application of their input

Power Plants Likely Covered by the Mercury and Air Toxics Standards (MATS)

EPA Pesticide Factsheets

The U.S. Environmental Protection Agency (EPA) has proposed Mercury and Air Toxics Standards (MATS) for power plants to limit mercury, acid gases and other toxic pollution from power plants. Using Google Earth, this page locates power plants in your state.

IMPROVEMENT IN AIR TOXICS METHODS FOR VOLATILE ORGANIC COMPOUNDS

EPA Science Inventory

Innovative and customized monitoring methods for air toxic volatile organic compounds (VOCs) are being developed for applications in exposure and trends monitoring. This task addresses the following applications of specific interest:

o Contributions to EPA Regional Monit...

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

PubMed

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

Effect of pyrolysis temperature and air flow on toxicity of gases from a polycarbonate polymer

NASA Technical Reports Server (NTRS)

Hilado, C. J.; Brick, V. E.; Brauer, D. P.

1978-01-01

A polycarbonate polymer was evaluated for toxicity of pyrolysis gases generated at various temperatures without forced air flow and with 1 L/min air flow, using the toxicity screening test method developed at the University of San Francisco. Time to various animal responses decreased with increasing pyrolysis temperature over the range from 500 C to 800 C. There appeared to be no significant toxic effects at 400 C and lower temperatures.

LARGE-SCALE PREDICTIONS OF MOBILE SOURCE CONTRIBUTIONS TO CONCENTRATIONS OF TOXIC AIR POLLUTANTS

EPA Science Inventory

This presentation shows concentrations and deposition of toxic air pollutants predicted by a 3-D air quality model, the Community Multi Scale Air Quality (CMAQ) modeling system. Contributions from both on-road and non-road mobile sources are analyzed.

Epidemiologic evidence for asthma and exposure to air toxics: linkages between occupational, indoor, and community air pollution research.

PubMed Central

Delfino, Ralph J

2002-01-01

Outdoor ambient air pollutant exposures in communities are relevant to the acute exacerbation and possibly the onset of asthma. However, the complexity of pollutant mixtures and etiologic heterogeneity of asthma has made it difficult to identify causal components in those mixtures. Occupational exposures associated with asthma may yield clues to causal components in ambient air pollution because such exposures are often identifiable as single-chemical agents (e.g., metal compounds). However, translating occupational to community exposure-response relationships is limited. Of the air toxics found to cause occupational asthma, only formaldehyde has been frequently investigated in epidemiologic studies of allergic respiratory responses to indoor air, where general consistency can be shown despite lower ambient exposures. The specific volatile organic compounds (VOCs) identified in association with occupational asthma are generally not the same as those in studies showing respiratory effects of VOC mixtures on nonoccupational adult and pediatric asthma. In addition, experimental evidence indicates that airborne polycyclic aromatic hydrocarbon (PAH) exposures linked to diesel exhaust particles (DEPs) have proinflammatory effects on airways, but there is insufficient supporting evidence from the occupational literature of effects of DEPs on asthma or lung function. In contrast, nonoccupational epidemiologic studies have frequently shown associations between allergic responses or asthma with exposures to ambient air pollutant mixtures with PAH components, including black smoke, high home or school traffic density (particularly truck traffic), and environmental tobacco smoke. Other particle-phase and gaseous co-pollutants are likely causal in these associations as well. Epidemiologic research on the relationship of both asthma onset and exacerbation to air pollution is needed to disentangle effects of air toxics from monitored criteria air pollutants such as particle mass

A FIELD VALIDATION OF TWO SEDIMENT-AMPHIPOD TOXICITY TESTS

EPA Science Inventory

A field validation study of two sediment-amphipod toxicity tests was conducted using sediment samples collected subtidally in the vicinity of a polycyclic aromatic hydrocarbon (PAH)-contaminated Superfund site in Elliott Bay, WA, USA. Sediment samples were collected at 30 stati...

Fisk-based criteria to support validation of detection methods for drinking water and air.

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacDonell, M.; Bhattacharyya, M.; Finster, M.

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 contaminantsmore » 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

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

EPA Pesticide Factsheets

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.

APPLICATION OF FINE SCALE AIR TOXICS MODELING WITH CMAQ TO HAPEM5

EPA Science Inventory

This paper provides a preliminary demonstration of the EPA neighborhood scale modeling paradigm for air toxics by linking concentration from the Community Multiscale Air Quality (CMAQ) modeling system to the fifth version of the Hazardous Pollutant Exposure Model (HAPEM5). For t...

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

PubMed

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.

Risk Assessment for Criteria Pollutants and Air Toxics in two Sites of Mexico City During 2003 Field Campaign

NASA Astrophysics Data System (ADS)

García, A. R.; Grutter, M. M.; Volkamer, R. M.

2007-05-01

An environmental risk assessment for criteria pollutants and air toxics in Mexico City is presented. The data used in the study were collected by FTIR and DOAS systems during the Mexico City Metropolitan Area field campaign on April 2003 (MCMA2003). The systems were deployed in two different sites: One in downtown (Merced) and the other in the south east (CENICA). Concentrations of criteria pollutants and air toxics were obtained every 5 min and were used to obtain hourly average concentrations and the month average for April. The concentration values were used to estimate the risks of acute and chronic exposure to ambient concentrations using risk measures like hazard index, life cancer probability, life lost expectancy and maximum individual cancer risk. Results revealed that both sites have similar risk values. For acute exposure, criteria pollutants have larger risks than air toxics, but air toxics have larger risks for chronic exposure. Ambient concentrations of benzene showed the largest carcinogenic risk of the measured air toxics.

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

PubMed

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.

EMISSIONS OF ORGANIC AIR TOXICS FROM OPEN ...

EPA Pesticide Factsheets

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

STRUCTURE-ACTIVITY APPROACHES AND DATA EXPLORATION TOOLS FOR PRIORITIZING AND ASSESSING THE TOXICITY OF HAZARDOUS AIR POLLUTANTS

EPA Science Inventory

STRUCTURE-ACTIVITY APPROACHES AND DATA EXPLORATION TOOLS FOR PRIORITIZING AND ASSESSING THE TOXICITY OF HAZARDOUS AIR POLLUTANTS

Hazardous Air Pollutants (HAPs) refers to a set of structurally diverse environmental chemicals, many with limited toxicity data, that have...

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

PubMed

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.

A METHOD OF ASSESSING AIR TOXICS CONCENTRATIONS IN URBAN AREAS USING MOBILE PLATFORM MEASUREMENTS

EPA Science Inventory

The objective of this paper is to demonstrate an approach to characterize the spatial variability in ambient air concentrations using mobile platform measurements. This approach may be useful for air toxic assessments in Environmental Justice applications, epidemiological studies...

Risk of leukemia in relation to exposure to ambient air toxics in pregnancy and early childhood.

PubMed

Heck, Julia E; Park, Andrew S; Qiu, Jiaheng; Cockburn, Myles; Ritz, Beate

2014-07-01

There are few established causes of leukemia, the most common type of cancer in children. Studies in adults suggest a role for specific environmental agents, but little is known about any effect from exposures in pregnancy to toxics in ambient air. In our case-control study, we ascertained 69 cases of acute lymphoblastic leukemia (ALL) and 46 cases of acute myeloid leukemia (AML) from California Cancer Registry records of children air toxics monitoring station between 1990 and 2007. Information on air toxics exposures was taken from community air monitors. We used logistic regression to estimate the risk of leukemia associated with one interquartile range increase in air toxic exposure. Risk of ALL was elevated with 3(rd) trimester exposure to polycyclic aromatic hydrocarbons (OR=1.16, 95% CI 1.04, 1.29), arsenic (OR=1.33, 95% CI 1.02, 1.73), benzene (OR=1.50, 95% CI 1.08, 2.09), and three other toxics related to fuel combustion. Risk of AML was increased with 3rd trimester exposure to chloroform (OR=1.30, 95% CI 1.00, 1.69), benzene (1.75, 95% CI 1.04, 2.93), and two other traffic-related toxics. During the child's first year, exposure to butadiene, ortho-xylene, and toluene increased risk for AML and exposure to selenium increased risk for ALL. Benzene is an established cause of leukemia in adults; this study supports that ambient exposures to this and other chemicals in pregnancy and early life may also increase leukemia risk in children. Copyright © 2013 Elsevier GmbH. All rights reserved.

RESOLVING FINE SCALE IN AIR TOXICS MODELING AND THE IMPORTANCE OF ITS SUB-GRID VARIABILITY FOR EXPOSURE ESTIMATES

EPA Science Inventory

This presentation explains the importance of the fine-scale features for air toxics exposure modeling. The paper presents a new approach to combine local-scale and regional model results for the National Air Toxic Assessment. The technique has been evaluated with a chemical tra...

IPM Analysis of the Final Mercury and Air Toxics Standards (MATS)

EPA Pesticide Factsheets

EPA used version 4.10_MATS of the Integrated Planning Model (IPM) to analyze the impact of the Mercury and Air Toxics Standards (MATS) rule on the U.S. electric power sector. Learn about the results and view links to documentation.

DETERMINANTS OF HUMAN EXPOSURES TO AIR TOXICS AND ASSOCIATED HEALTH EFFECTS

EPA Science Inventory

Individuals are exposed to wide variety of air toxics in various indoor and outdoor microenvironments during the course of their daily activities. Sources of emissions include a wide variety of indoor and outdoor sources, including stationary and mobile sources, building material...

Evaluation of a possible association of urban air toxics and asthma.

PubMed Central

Leikauf, G D; Kline, S; Albert, R E; Baxter, C S; Bernstein, D I; Buncher, C R

1995-01-01

The prevalence of asthma, measured either as the frequency of hospital admissions or number of deaths attributed to asthma, has increased over the last 15 to 20 years. Rapid increases in disease prevalence are more likely to be attributable to environmental than genetic factors. Inferring from past associations between air pollution and asthma, it is feasible that changes in the ambient environment could contribute to this increase in morbidity and mortality. Scientific evaluation of the links between air pollution and the exacerbation of asthma is incomplete, however. Currently, criteria pollutants [SOx, NOx, O3, CO, Pb, particulate matter (PM10)] and other risk factors (exposure to environmental tobacco smoke, volatile organic compounds, etc.) are constantly being evaluated as to their possible contributions to this situation. Data from these studies suggest that increases in respiratory disease are associated with exposures to ambient concentrations of particulate and gaseous pollutants. Similarly, exposure to environmental tobacco smoke, also a mixture of particulate and gaseous air toxics, has been associated with an increase in asthma among children. In addition, current associations of adverse health effects with existing pollution measurements are often noted at concentrations below those that produce effects in controlled animal and human exposures to each pollutant alone. These findings imply that adverse responses are augmented when persons are exposed to irritant mixtures of particles and gases and that current measurements of air pollution are, in part, indirect in that the concentrations of criteria pollutants are acting as surrogates of our exposure to a complex mixture. Other irritant air pollutants, including certain urban air toxics, are associated with asthma in occupational settings and may interact with criteria pollutants in ambient air to exacerbate asthma. An evaluation of dose-response information for urban air toxics and biological

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

PubMed

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.

CORONA DESTRUCTION: AN INNOVATIVE CONTROL TECHNOLOGY FOR VOCS AND AIR TOXICS

EPA Science Inventory

This paper discusses the work and results to date leading to the demonstration of the corona destruction process at pilot scale. The research effort in corona destruction of volatile organic compounds (VOCs) and air toxics has shown significant promise for providing a valuable co...

ASTM Validates Air Pollution Test Methods

ERIC Educational Resources Information Center

Chemical and Engineering News, 1973

1973-01-01

The American Society for Testing and Materials (ASTM) has validated six basic methods for measuring pollutants in ambient air as the first part of its Project Threshold. Aim of the project is to establish nationwide consistency in measuring pollutants; determining precision, accuracy and reproducibility of 35 standard measuring methods. (BL)

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

EPA Pesticide Factsheets

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.

Validation of the Asthma Illness Representation Scale-Spanish (AIRS-S).

PubMed

Sidora-Arcoleo, Kimberly Joan; Feldman, Jonathan; Serebrisky, Denise; Spray, Amanda

2010-05-01

To expand knowledge surrounding parental illness representations (IRs) of their children's asthma, it is imperative that culturally appropriate survey instruments are developed and validated for use in clinical and research settings. The Asthma Illness Representation Scale (AIRS) provides a structured assessment of the key components of asthma IRs, allowing the health care provider (HCP) to quickly identify areas of discordance with the professional model of asthma management. The English AIRS was developed and validated among a geographically and ethnically diverse sample. The authors present the validation results of the AIRS-S (Spanish) from a sample of Mexican and Puerto Rican parents. The AIRS was translated and back translated per approved methodologies. Factor analysis, internal reliability, external validity, and 2-week test-retest reliability (on a subsample) were carried out and results compared with the validated English version. Data were obtained from 80 Spanish-speaking Mexican and Puerto Rican parents of children with asthma. The sample was recruited from two school-based health centers and a free medical clinic in Phoenix, Arizona, and a hospital-based asthma clinic in Bronx, New York. The original Nature of Asthma Symptoms, Facts About Asthma, and Attitudes Towards Medication Use subscales emerged. Remaining factors were a mixture of items with no coherent or theoretical distinction between them. Interpretation of results is limited due to not meeting the minimum requirement of 5 observations/item. Cronbach's alpha coefficients for the total score (alpha = .77) and majority of subscales (alpha range = .53-.77) were acceptable and consistent with the English version. Parental reports of a positive relationship with the HCP significantly predicted AIRS scores congruent with the professional model; longer asthma duration was associated with beliefs aligned with the lay model; and AIRS scores congruent with the professional model were related to lower

Development of probabilistic emission inventories of air toxics for Jacksonville, Florida, USA.

PubMed

Zhao, Yuchao; Frey, H Christopher

2004-11-01

Probabilistic emission inventories were developed for 1,3-butadiene, mercury (Hg), arsenic (As), benzene, formaldehyde, and lead for Jacksonville, FL. To quantify inter-unit variability in empirical emission factor data, the Maximum Likelihood Estimation (MLE) method or the Method of Matching Moments was used to fit parametric distributions. For data sets that contain nondetected measurements, a method based upon MLE was used for parameter estimation. To quantify the uncertainty in urban air toxic emission factors, parametric bootstrap simulation and empirical bootstrap simulation were applied to uncensored and censored data, respectively. The probabilistic emission inventories were developed based on the product of the uncertainties in the emission factors and in the activity factors. The uncertainties in the urban air toxics emission inventories range from as small as -25 to +30% for Hg to as large as -83 to +243% for As. The key sources of uncertainty in the emission inventory for each toxic are identified based upon sensitivity analysis. Typically, uncertainty in the inventory of a given pollutant can be attributed primarily to a small number of source categories. Priorities for improving the inventories and for refining the probabilistic analysis are discussed.

Hybrid Modeling Approach to Estimate Exposures of Hazardous Air Pollutants (HAPs) for the National Air Toxics Assessment (NATA).

PubMed

Scheffe, Richard D; Strum, Madeleine; Phillips, Sharon B; Thurman, James; Eyth, Alison; Fudge, Steve; Morris, Mark; Palma, Ted; Cook, Richard

2016-11-15

A hybrid air quality model has been developed and applied to estimate annual concentrations of 40 hazardous air pollutants (HAPs) across the continental United States (CONUS) to support the 2011 calendar year National Air Toxics Assessment (NATA). By combining a chemical transport model (CTM) with a Gaussian dispersion model, both reactive and nonreactive HAPs are accommodated across local to regional spatial scales, through a multiplicative technique designed to improve mass conservation relative to previous additive methods. The broad scope of multiple pollutants capturing regional to local spatial scale patterns across a vast spatial domain is precedent setting within the air toxics community. The hybrid design exhibits improved performance relative to the stand alone CTM and dispersion model. However, model performance varies widely across pollutant categories and quantifiably definitive performance assessments are hampered by a limited observation base and challenged by the multiple physical and chemical attributes of HAPs. Formaldehyde and acetaldehyde are the dominant HAP concentration and cancer risk drivers, characterized by strong regional signals associated with naturally emitted carbonyl precursors enhanced in urban transport corridors with strong mobile source sector emissions. The multiple pollutant emission characteristics of combustion dominated source sectors creates largely similar concentration patterns across the majority of HAPs. However, reactive carbonyls exhibit significantly less spatial variability relative to nonreactive HAPs across the CONUS.

Residential exposure to air toxics is linked to lower grade point averages among school children in El Paso, Texas, USA

PubMed Central

Clark-Reyna, Stephanie E.; Grineski, Sara E.; Collins, Timothy W.

2015-01-01

Children in low-income neighborhoods tend to be disproportionately exposed to environmental toxicants. This is cause for concern because exposure to environmental toxicants negatively affect health, which can impair academic success. To date, it is unknown if associations between air toxics and academic performance found in previous school-level studies persist when studying individual children. In pairing the National Air Toxics Assessment (NATA) risk estimates for respiratory and diesel particulate matter risk disaggregated by source, with individual-level data collected through a mail survey, this paper examines the effects of exposure to residential environmental toxics on academic performance for individual children for the first time and adjusts for school-level effects using generalized estimating equations. We find that higher levels of residential air toxics, especially those from non-road mobile sources, are statistically significantly associated with lower grade point averages among fourth and fifth grade school children in El Paso (Texas, USA). PMID:27034529

Measuring financial toxicity as a clinically relevant patient-reported outcome: The validation of the COmprehensive Score for financial Toxicity (COST).

PubMed

de Souza, Jonas A; Yap, Bonnie J; Wroblewski, Kristen; Blinder, Victoria; Araújo, Fabiana S; Hlubocky, Fay J; Nicholas, Lauren H; O'Connor, Jeremy M; Brockstein, Bruce; Ratain, Mark J; Daugherty, Christopher K; Cella, David

2017-02-01

Cancer and its treatment lead to increased financial distress for patients. To the authors' knowledge, to date, no standardized patient-reported outcome measure has been validated to assess this distress. Patients with AJCC Stage IV solid tumors receiving chemotherapy for at least 2 months were recruited. Financial toxicity was measured by the COmprehensive Score for financial Toxicity (COST) measure. The authors collected data regarding patient characteristics, clinical trial participation, health care use, willingness to discuss costs, psychological distress (Brief Profile of Mood States [POMS]), and health-related quality of life (HRQOL) as measured by the Functional Assessment of Cancer Therapy: General (FACT-G) and the European Organization for Research and Treatment of Cancer (EORTC) QOL questionnaires. Test-retest reliability, internal consistency, and validity of the COST measure were assessed using standard-scale construction techniques. Associations between the resulting factors and other variables were assessed using multivariable analyses. A total of 375 patients with advanced cancer were approached, 233 of whom (62.1%) agreed to participate. The COST measure demonstrated high internal consistency and test-retest reliability. Factor analyses revealed a coherent, single, latent variable (financial toxicity). COST values were found to be correlated with income (correlation coefficient [r] = 0.28; P<.001), psychosocial distress (r = -0.26; P<.001), and HRQOL, as measured by the FACT-G (r = 0.42; P<.001) and by the EORTC QOL instruments (r = 0.33; P<.001). Independent factors found to be associated with financial toxicity were race (P = .04), employment status (P<.001), income (P = .003), number of inpatient admissions (P = .01), and psychological distress (P = .003). Willingness to discuss costs was not found to be associated with the degree of financial distress (P = .49). The COST measure demonstrated reliability and

PROCEEDINGS OF THE 1992 EPA/AWMA INTERNATIONAL SYMPOSIUM MEASUREMENT OF TOXIC AND RELATED AIR POLLUTANTS

EPA Science Inventory

The 1992 USEPA/AWMA International Symposium Measurement of Toxic and Related Air Pollutants was held in Durham, NC on May 4-9, 1992. his yearly symposium is sponsored by the Atmospheric Research and Exposure Assessment Laboratory and the Air & Waste Management Association. he tec...

CRITERIA AND AIR TOXIC EMISSIONS FROM IN-USE, LOW EMISSION VEHICLES (LEVS)

EPA Science Inventory

The U.S. Environmental Protection Agency implemented a program to identify tailpipe emissions of criteria and air toxic contaminants from in-use, light-duty Low Emission Vehicles (LEVs). EPA recruited twenty-five LEVs in 2002, and measured emissions on a chassis dynamometer usin...

APPLICATIONS ANALYSIS REPORT: TOXIC TREATMENTS, IN-SITU STEAM/HOT-AIR STRIPPING TECHNOLOGY

EPA Science Inventory

This document is an evaluation of the performance of the Toxic Treatments (USA), Inc., (TTUSA) in situ steam/hot-air stripping technology and its applicability as an on-site treatment technique for hazardous waste site soil cleanup of volatile and semivolatile contaminants. Both ...

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

PubMed Central

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

2012-01-01

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 <2,500 g) using logistic regression adjusted for maternal age, race/ethnicity, education, parity, infant gestational age, and gestational age squared. Odds of term LBW increased 2%–5% (95% confidence intervals ranged from 1.00 to 1.09) per interquartile-range increase in LUR-modeled estimates and monitoring-based air toxics exposure estimates in the entire pregnancy, the third trimester, and the last month of pregnancy. Models stratified by monitoring station (to investigate air toxics associations based solely on temporal 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. PMID:22586068

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.

PubMed

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 <2,500 g) using logistic regression adjusted for maternal age, race/ethnicity, education, parity, infant gestational age, and gestational age squared. Odds of term LBW increased 2%-5% (95% confidence intervals ranged from 1.00 to 1.09) per interquartile-range increase in LUR-modeled estimates and monitoring-based air toxics exposure estimates in the entire pregnancy, the third trimester, and the last month of pregnancy. Models stratified by monitoring station (to investigate air toxics associations based solely on temporal 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.

Constructing, Quantifying, and Validating an Adverse Outcome Pathway for Vascular Developmental Toxicity

EPA Science Inventory

Constructing, Quantifying, and Validating an Adverse Outcome Pathway for Vascular Developmental Toxicity The adverse outcome pathway (AOP) for embryonic vascular disruption1 leading to a range of adverse prenatal outcomes was recently entered into the AOP wiki and accepted as par...

The validation of AIRS retrievals

NASA Technical Reports Server (NTRS)

Fetzer, Eric J.; Olsen, Edward T.; Chen, Luke L.; Hagan, Denise E.; Fishbein, Evan; McMillin, Larry; Zhou, Jiang; McMillan, Wallace W.

2003-01-01

The initial validation of Atmospheric Infrared Sounder (SIRS) experiment retrievals were completed in August 2003 as part of public release of version 3.0 data. The associated analyses are reported at http://daac.gsfc.nasa.gov/atmodyn/airs/, where data may be accessed. Here we describe some of those analyses, with an emphasis on cloud cleared radiances, atmospheric temperature profiles, sea surface temperature, total water vapor and atmospheric water vapor profiles. The results are applicable over ocean in the latitude band +/-40 degrees.

MODELING AIR TOXICS AND PM 2.5 CONCENTRATION FIELDS AS A MEANS FOR FACILITATING HUMAN EXPOSURE ASSESSMENTS

EPA Science Inventory

The capability of the US EPA Models-3/Community Multiscale Air Quality (CMAQ) modeling system is extended to provide gridded ambient air quality concentration fields at fine scales. These fields will drive human exposure to air toxics and fine particulate matter (PM2.5) models...

Development and Validation of the Air Force Cyber Intruder Alert Testbed (CIAT)

DTIC Science & Technology

2016-07-27

Validation of the Air Force Cyber Intruder Alert Testbed (CIAT) 5a. CONTRACT NUMBER FA8650-16-C-6722 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...network analysts. Therefore, a new cyber STE focused on network analysts called the Air Force Cyber Intruder Alert Testbed (CIAT) was developed. This...Prescribed by ANSI Std. Z39-18 Development and Validation of the Air Force Cyber Intruder Alert Testbed (CIAT) Gregory Funke, Gregory Dye, Brett Borghetti

Dynamic Imaging Grade of Swallowing Toxicity (DIGEST): Scale Development and Validation

PubMed Central

Hutcheson, Katherine A.; Barrow, Martha P.; Barringer, Denise A.; Knott, Jodi K.; Lin, Heather Y.; Weber, Randal S.; Fuller, Clifton D.; Lai, Stephen Y.; Alvarez, Clare; Raut, Janhavi; Lazarus, Cathy L.; May, Annette; Patterson, JoAnne; Roe, Justin W.G.; Starmer, Heather M.; Lewin, Jan S.

2016-01-01

Purpose NCI’s Common Terminology Criteria for Adverse Events (CTCAE) is the universal framework for toxicity reporting in oncology trials. We sought to develop a CTCAE-compatible modified barium swallow (MBS) grade for the purpose of grading pharyngeal dysphagia as a toxicity endpoint in cooperative group organ preservation trials for head and neck cancer (HNC). We hypothesized that a 5-point CTCAE-compatible MBS grade (“DIGEST”) based on the interaction of pharyngeal residue and laryngeal penetration/aspiration ratings is feasible and psychometrically sound. Methods A modified Delphi exercise was conducted for content validation, expert consensus, and operationalization of DIGEST criteria. Two blinded raters scored 100 MBS conducted before or after surgical or non-surgical organ preservation. Intra- and inter-rater reliability were tested by weighted Kappa. Criterion validity against OPSE, MBSImP™©, MDADI, and PSS-HN was assessed with one-way ANOVA and post hoc pairwise comparisons between DIGEST grades. Results Intra-rater reliability was excellent (weighted Kappa=0.82–0.84) with substantial to almost perfect agreement between raters (weighted Kappa=0.67–0.81). DIGEST significantly discriminated levels of pharyngeal pathophysiology (MBSImP™©: r=0.77, p<0.0001), swallow efficiency (OPSE: r=−0.56, p<0.0001), perceived dysphagia (MDADI: r=−0.41, p<0.0001), and oral intake (PSS-HN diet: r=−0.49, p<0.0001). Conclusions With the development of DIGEST, we have adapted MBS rating to the CTCAE nomenclature of ordinal toxicity grading used in oncology trials. DIGEST offers a psychometrically sound measure for HNC clinical trials and investigations of toxicity profiles, dose-response, and predictive modeling. PMID:27564246

Enhanced data validation strategy of air quality monitoring network.

PubMed

Harkat, Mohamed-Faouzi; Mansouri, Majdi; Nounou, Mohamed; Nounou, Hazem

2018-01-01

Quick validation and detection of faults in measured air quality data is a crucial step towards achieving the objectives of air quality networks. Therefore, the objectives of this paper are threefold: (i) to develop a modeling technique that can be used to predict the normal behavior of air quality variables and help provide accurate reference for monitoring purposes; (ii) to develop fault detection method that can effectively and quickly detect any anomalies in measured air quality data. For this purpose, a new fault detection method that is based on the combination of generalized likelihood ratio test (GLRT) and exponentially weighted moving average (EWMA) will be developed. GLRT is a well-known statistical fault detection method that relies on maximizing the detection probability for a given false alarm rate. In this paper, we propose to develop GLRT-based EWMA fault detection method that will be able to detect the changes in the values of certain air quality variables; (iii) to develop fault isolation and identification method that allows defining the fault source(s) in order to properly apply appropriate corrective actions. In this paper, reconstruction approach that is based on Midpoint-Radii Principal Component Analysis (MRPCA) model will be developed to handle the types of data and models associated with air quality monitoring networks. All air quality modeling, fault detection, fault isolation and reconstruction methods developed in this paper will be validated using real air quality data (such as particulate matter, ozone, nitrogen and carbon oxides measurement). Copyright © 2017 Elsevier Inc. All rights reserved.

Toxic Warfare

DTIC Science & Technology

2002-02-01

Prepared for the United States Air Force Approved for public release; distribution unlimited Theodore Karasik Project AIR FORCE R TOXIC WARFARE...Report Documentation Page Report Date 000002002 Report Type N/A Dates Covered (from... to) - Title and Subtitle Toxic Warfare Contract Number Grant...310) 451-6915; Email: order@rand.org Library of Congress Cataloging-in-Publication Data Karasik, Theodore William. Toxic warfare / Theodore Karasik

Fact Sheet: Final Air Toxics Standards for Area Sources in the Chemical Manufacturing Industry

EPA Pesticide Factsheets

Fact sheet on the national air toxics standards issued October 16, 2009 by the Environmental Protection Agency (EPA) for smaller-emitting sources, known as area sources, in the chemical manufacturing industry.

Validation of the Dynamic Direct Exposure Method for Toxicity Testing of Diesel Exhaust In Vitro

PubMed Central

Hayes, Amanda; Bakand, Shahnaz

2013-01-01

Diesel exhaust emission is a major health concern because of the complex nature of its gaseous content (e.g., NO2, NO, CO, and CO2) and high concentration of particulate matter (PM) less than 2.5 μm which allows for deeper penetration into the human pulmonary system upon inhalation. The aim of this research was to elucidate the potential toxic effects of diesel exhaust on a human pulmonary-based cellular system. Validation of a dynamic direct exposure method for both laboratory (230 hp Volvo truck engine) and field (Volkswagen Passat passenger car) diesel engines, at idle mode, was implemented. Human pulmonary type II epithelial cells (A549) grown on porous membranes were exposed to unmodified diesel exhaust at a low flow rate (37.5 mL/min). In parallel, diesel emission sampling was also conducted using real-time air monitoring techniques. Induced cellular effects were assessed using a range of in vitro cytotoxicity assays (MTS, ATP, and NRU). Reduction of cell viability was observed in a time-dependent manner following 30–60 mins of exposure with NRU as the most sensitive assay. The results suggest that the dynamic direct exposure method has the potential to be implemented for both laboratory- and field-based in vitro toxicity studies of diesel exhaust emissions. PMID:23986878

AIRS Retrieval Validation During the EAQUATE

NASA Technical Reports Server (NTRS)

Zhou, Daniel K.; Smith, William L.; Cuomo, Vincenzo; Taylor, Jonathan P.; Barnet, Christopher D.; DiGirolamo, Paolo; Pappalardo, Gelsomina; Larar, Allen M.; Liu, Xu; Newman, Stuart M.

2006-01-01

Atmospheric and surface thermodynamic parameters retrieved with advanced hyperspectral remote sensors of Earth observing satellites are critical for weather prediction and scientific research. The retrieval algorithms and retrieved parameters from satellite sounders must be validated to demonstrate the capability and accuracy of both observation and data processing systems. The European AQUA Thermodynamic Experiment (EAQUATE) was conducted mainly for validation of the Atmospheric InfraRed Sounder (AIRS) on the AQUA satellite, but also for assessment of validation systems of both ground-based and aircraft-based instruments which will be used for other satellite systems such as the Infrared Atmospheric Sounding Interferometer (IASI) on the European MetOp satellite, the Cross-track Infrared Sounder (CrIS) from the NPOESS Preparatory Project and the following NPOESS series of satellites. Detailed inter-comparisons were conducted and presented using different retrieval methodologies: measurements from airborne ultraspectral Fourier transform spectrometers, aircraft in-situ instruments, dedicated dropsondes and radiosondes, and ground based Raman Lidar, as well as from the European Center for Medium range Weather Forecasting (ECMWF) modeled thermal structures. The results of this study not only illustrate the quality of the measurements and retrieval products but also demonstrate the capability of these validation systems which are put in place to validate current and future hyperspectral sounding instruments and their scientific products.

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

NASA Astrophysics Data System (ADS)

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.

EPA'S CONTROL TECHNOLOGY APPROACH TO ASSISTING STATES AND REGIONS WITH AIR TOXICS PROBLEMS: FIVE CASE STUDIES

EPA Science Inventory

The paper discusses a new U.S. strategy to reduce public exposure to toxic air pollutants in the ambient air. he strategy calls for state and local authorities to take on more of the lead regulatory role. he shift in emphasis and responsibility prompted EPA's Offices of Research ...

Fuel-cycle emissions for conventional and alternative fuel vehicles : an assessment of air toxics

DOT National Transportation Integrated Search

2000-08-01

This report provides information on recent efforts to use the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) fuel-cycle model to estimate air toxics emissions. GREET, developed at Argonne National Laboratory, currentl...

An Evaluation of EPA's National-Scale Air Toxics Assessment (NATA): Comparison with Benzene Measurements in Detroit, Michigan

EPA Science Inventory

The U.S. EPA periodically evaluates ambient concentrations, human exposures, and health risks for 180 hazardous air pollutants plus diesel particulate matter using modeled estimates from the National-Scale Air Toxics Assessment (NATA). NATA publishes estimates at the spatial reso...

EMISSIONS OF AIR TOXICS FROM A SIMULATED CHARCOAL KILN EQUIPPED WITH AN AFTERBURNER

EPA Science Inventory

The report discusses emissions of air toxics from a simulated charcoal kiln equipped with an afterburner. A laboratory-scale simulator was constructed and tested to determine if it could be used to produce charcoal that was similar to that produced in Missouri-type charcoal kilns...

Adaptation of a military FTS to civilian air toxics measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Engel, J.R.; Dorval, R.K.

1994-12-31

In many ways, the military problem of chemical agent detection is similar to the civilian problem of toxic and related air pollutants detection. A recent program to design a next generation Fourier transform spectrometer (FTS) based chemical agent detection system has been funded by the US Army. This program has resulted in an FTS system that has a number of characteristics that make it suitable for applications to the civilian measurement problem. Low power, low weight, and small size lead to low installation, operating and maintenance costs. Innovative use of diode lasers in place of HeNe reference sources leads tomore » long lifetimes and high reliability. Absolute scan position servos allow for highly efficient offset scanning. This paper will relate the performance of this system to present air monitoring requirements.« less

Perspectives on Validation of High-Throughput Assays Supporting 21st Century Toxicity Testing

EPA Science Inventory

In vitro high-throughput screening (HTS) assays are seeing increasing use in toxicity testing. HTS assays can simultaneously test many chemicals but have seen limited use in the regulatory arena, in part because of the need to undergo rigorous, time-consuming formal validation. ...

Report: EPA’s Method for Calculating Air Toxics Emissions for Reporting Results Needs Improvement

EPA Pesticide Factsheets

Report #2004-P-00012, March 31, 2004. Although the methods by which air toxics emissions are estimated have improved substantially, unvalidated assumptions and other limitations underlying the NTI continue to impact its use as a GPRA performance measure.

Petition for EPA action to protect communities from oil and gas wells toxic air pollution

EPA Pesticide Factsheets

Petition submitted by Earthjustice urging EPA to list oil and gas wells and associated equipment as an area sourcecategory and set national air toxics standards to protect public health from these sources.

Air toxics and early childhood acute lymphocytic leukemia in Texas, a population based case control study.

PubMed

Symanski, Elaine; Tee Lewis, P Grace; Chen, Ting-Yu; Chan, Wenyaw; Lai, Dejian; Ma, Xiaomei

2016-06-14

Traffic exhaust, refineries and industrial facilities are major sources of air toxics identified by the U.S. Environmental Protection Agency (U.S. EPA) for their potential risk to human health. In utero and early life exposures to air toxics such as benzene and 1,3-butadiene, which are known leukemogens in adults, may play an etiologic role in childhood leukemia that comprises the majority of pediatric cancers. We conducted a population based case-control study to examine individual effects of benzene, 1,3-butadiene and polycyclic organic matter (POM) in ambient residential air on acute lymphocytic leukemia (ALL) diagnosed in children under age 5 years in Texas from 1995-2011. Texas Cancer Registry cases were linked to birth records and then were frequency matched by birth month and year to 10 population-based controls. Maternal and infant characteristics from birth certificates were abstracted to obtain information about potential confounders. Modelled estimates of benzene, 1,3-butadiene and POM exposures at the census tract level were assigned by linking geocoded maternal addresses from birth certificates to U.S. EPA National-Scale Air Toxics Assessment data for single and co-pollutant statistical analyses. Mixed-effects logistic regression models were applied to evaluate associations between air toxics and childhood leukemia. In adjusted single pollutant models, odds of childhood leukemia among mothers with the highest ambient air exposures compared to those in the lowest quartile were 1.11 (95 % CI: 0.94-1.32) for POM, 1.17 (95 % CI: 0.98-1.39) for benzene and 1.29 (95 % CI: 1.08-1.52) for 1,3-butadiene. In co-pollutant models, odds ratios for childhood leukemia remained elevated for 1,3-butadiene but were close to the null value for benzene and POM. We observed positive associations between 1,3-butadiene and childhood leukemia in single and co-pollutant models whereas effect estimates from single pollutant models were diminished for benzene and POM in co

Temporal and modal characterization of DoD source air toxic emission factors: final report

EPA Science Inventory

This project tested three, real-/near real-time monitoring techniques to develop air toxic emission factors for Department of Defense (DoD) platform sources. These techniques included: resonance enhanced multi photon ionization time of flight mass spectrometry (REMPI-TOFMS) for o...

Validation of the proteasome as a therapeutic target in Plasmodium using an epoxyketone inhibitor with parasite-specific toxicity

PubMed Central

Li, Hao; Ponder, Elizabeth L.; Verdoes, Martijn; Asbjornsdottir, Kristijana H.; Deu, Edgar; Edgington, Laura E.; Lee, Jeong Tae; Kirk, Christopher J.; Demo, Susan D.; Williamson, Kim C.; Bogyo, Matthew

2012-01-01

Summary The Plasmodium proteasome has been suggested to be a potential anti-malarial drug target, however toxicity of inhibitors has prevented validation of this enzyme in vivo. We report here a screen of a library of 670 analogs of the recently FDA approved inhibitor, carfilzomib, to identify compounds that selectively kill parasites. We identified one compound, PR3, that has significant parasite killing activity in vitro but dramatically reduced toxicity in host cells. We found that this parasite-specific toxicity is not due to selective targeting of the Plasmodium proteasome over the host proteasome, but instead is due to a lack of activity against one of the human proteasome subunits. Subsequently, we used PR3 to significantly reduce parasite load in P. berghei infected mice without host toxicity, thus validating the proteasome as a viable anti-malarial drug target. PMID:23142757

Temporal and Modal Characterization of DoD Source Air Toxic Emission Factors

DTIC Science & Technology

2010-04-01

Deviation RTP Research Triangle Park RWS Roadway Simulator S/N Signal Noise SDA Spray Dryer Catwalk Area STP Standard Pressure SVOC Semi...shutdown, and stationary idle conditions. A journal paper detailing the performance of REMPI-TOFMS in characterizing real-time air toxic emissions...the whole (benzene) dataset. The results are currently (July, 2009) being written into a paper prime- authored by Battelle. xvii

An investigation of new toxicity test method performance in validation studies: 1. Toxicity test methods that have predictive capacity no greater than chance.

PubMed

Bruner, L H; Carr, G J; Harbell, J W; Curren, R D

2002-06-01

An approach commonly used to measure new toxicity test method (NTM) performance in validation studies is to divide toxicity results into positive and negative classifications, and the identify true positive (TP), true negative (TN), false positive (FP) and false negative (FN) results. After this step is completed, the contingent probability statistics (CPS), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) are calculated. Although these statistics are widely used and often the only statistics used to assess the performance of toxicity test methods, there is little specific guidance in the validation literature on what values for these statistics indicate adequate performance. The purpose of this study was to begin developing data-based answers to this question by characterizing the CPS obtained from an NTM whose data have a completely random association with a reference test method (RTM). Determining the CPS of this worst-case scenario is useful because it provides a lower baseline from which the performance of an NTM can be judged in future validation studies. It also provides an indication of relationships in the CPS that help identify random or near-random relationships in the data. The results from this study of randomly associated tests show that the values obtained for the statistics vary significantly depending on the cut-offs chosen, that high values can be obtained for individual statistics, and that the different measures cannot be considered independently when evaluating the performance of an NTM. When the association between results of an NTM and RTM is random the sum of the complementary pairs of statistics (sensitivity + specificity, NPV + PPV) is approximately 1, and the prevalence (i.e., the proportion of toxic chemicals in the population of chemicals) and PPV are equal. Given that combinations of high sensitivity-low specificity or low specificity-high sensitivity (i.e., the sum of the sensitivity and

EPA's control technology approach to assisting states and regions with air toxics problems: Five case studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nolen, S.L.; Dimmick, W.F.

1990-10-01

The Environmental Protection Agency (EPA) announced in June 1985 a new strategy to reduce public exposure to toxic air pollutants in the ambient air. Over the next 5-8 years, the strategy called for State and Local authorities to take on more of the lead regulatory role, with the Agency providing technical and financial assistance to their efforts. The shift in emphasis and responsibility from the Federal level to State and Local air toxics programs and the need to transfer expertise from the Federal level to the appropriate State or Local level prompted EPA's Office of Research and Development (ORD) andmore » EPA's Office of Air Quality Planning and Standards (OAQPS) to develop and implement an innovative technical assistance program. This program is called the Control Technology Center (CTC). It has since been expanded to include technical assistance in the area of control of air toxics, particulate matter, and volatile organic compounds (VOCs); emission measurements; and other areas where expertise is available to ORD and OAQPS. During the CTC's first year of operation, operating guidelines were developed and three categories of technical assistance were established. These categories are telephone HOTLINE calls, direct engineering assistance, and technical guidance projects. The CTC HOTLINE is a special telephone number which State and Local Agencies can call for easy access to EPA personnel who can provide prompt assistance in a variety of ways including discussions, references to pertinent literature, and referrals to other EPA personnel. In some cases, a HOTLINE call will require more in-depth engineering analysis indicating a need for direct engineering assistance.« less

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

PubMed

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 < 0.001). Compared to outdoors, indoor PM contained more silicate (36% of 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.

OECD validation study to assess intra- and inter-laboratory reproducibility of the zebrafish embryo toxicity test for acute aquatic toxicity testing.

PubMed

Busquet, François; Strecker, Ruben; Rawlings, Jane M; Belanger, Scott E; Braunbeck, Thomas; Carr, Gregory J; Cenijn, Peter; Fochtman, Przemyslaw; Gourmelon, Anne; Hübler, Nicole; Kleensang, André; Knöbel, Melanie; Kussatz, Carola; Legler, Juliette; Lillicrap, Adam; Martínez-Jerónimo, Fernando; Polleichtner, Christian; Rzodeczko, Helena; Salinas, Edward; Schneider, Katharina E; Scholz, Stefan; van den Brandhof, Evert-Jan; van der Ven, Leo T M; Walter-Rohde, Susanne; Weigt, Stefan; Witters, Hilda; Halder, Marlies

2014-08-01

The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were analytically confirmed for 11 chemicals. Newly fertilised zebrafish eggs (20/concentration and control) were exposed for 96h to chemicals. Four apical endpoints were recorded daily as indicators of acute lethality: coagulation of the embryo, lack of somite formation, non-detachment of the tail bud from the yolk sac and lack of heartbeat. Results (LC50 values for 48/96h exposure) show that the ZFET is a robust method with a good intra- and inter-laboratory reproducibility (CV<30%) for most chemicals and laboratories. The reproducibility was lower (CV>30%) for some very toxic or volatile chemicals, and chemicals tested close to their limit of solubility. The ZFET is now available as OECD Test Guideline 236. Considering the high predictive capacity of the ZFET demonstrated by Belanger et al. (2013) in their retrospective analysis of acute fish toxicity and fish embryo acute toxicity data, the ZFET is ready to be considered for acute fish toxicity for regulatory purposes. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Geographic boundaries in breast, lung and colorectal cancers in relation to exposure to air toxics in Long Island, New York

PubMed Central

Jacquez, Geoffrey M; Greiling, Dunrie A

2003-01-01

Background This two-part study employs several statistical techniques to evaluate the geographic distribution of breast cancer in females and colorectal and lung cancers in males and females in Nassau, Queens, and Suffolk counties, New York, USA. In this second paper, we compare patterns in standardized morbidity ratios (SMR values), calculated from New York State Department of Health (NYSDOH) data, to geographic patterns in overall predicted risk (OPR) from air toxics using exposures estimated in the USEPA National Air Toxics Assessment database. Results We identified significant geographic boundaries in SMR and OPR. We found little or no association between the SMR of colorectal and breast cancers and the OPR for each cancer from exposure to the air toxics. We did find boundaries in male and female lung cancer SMR and boundaries in lung cancer OPR to be closer to one another than expected. Conclusion While consistent with a causal relationship between air toxics and lung cancer incidence, the boundary analysis does not demonstrate the existence of a causal relationship. However, now that the areas of overlap between boundaries in lung cancer incidence and potential airborne exposures have been identified, we can begin to evaluate local- as well as large-scale determinants of lung cancer. PMID:12633502

Characterization and validation of sampling and analytical methods for mycotoxins in workplace air.

PubMed

Jargot, Danièle; Melin, Sandrine

2013-03-01

Mycotoxins are produced by certain plant or foodstuff moulds under growing, transport or storage conditions. They are toxic for humans and animals, some are carcinogenic. Methods to monitor occupational exposure to seven of the most frequently occurring airborne mycotoxins have been characterized and validated. Experimental aerosols have been generated from naturally contaminated particles for sampler evaluation. Air samples were collected on foam pads, using the CIP 10 personal aerosol sampler with its inhalable health-related aerosol fraction selector. The samples were subsequently solvent extracted from the sampling media, cleaned using immunoaffinity (IA) columns and analyzed by liquid chromatography with fluorescence detection. Ochratoxin A (OTA) or fumonisin and aflatoxin derivatives were detected and quantified. The quantification limits were 0.015 ng m(-3) OTA, 1 ng m(-3) fumonisins or 0.5 pg m(-3) aflatoxins, with a minimum dust concentration level of 1 mg m(-3) and a 4800 L air volume sampling. The methods were successfully applied to field measurements, which confirmed that workers could be exposed when handling contaminated materials. It was observed that airborne particles may be more contaminated than the bulk material itself. The validated methods have measuring ranges fully adapted to the concentrations found in the workplace. Their performance meets the general requirements laid down for chemical agent measurement procedures, with an expanded uncertainty less than 50% for most mycotoxins. The analytical uncertainty, comprised between 14 and 24%, was quite satisfactory given the low mycotoxin amounts, when compared to the food benchmarks. The methods are now user-friendly enough to be adopted for personal workplace sampling. They will later allow for mycotoxin occupational risk assessment, as only very few quantitative data have been available till now.

AIR TOXICS MODELING FROM LOCAL TO REGIONAL SCALES TO SUPPORT THE 2002 MULTIPOLLUTANT ASSESSMENT

EPA Science Inventory

This research focuses on developing models that can describe the chemical and physical processes affecting concentrations of toxic air pollutants in the atmosphere, at spatial scales, ranging from local (< 1 km) to regional (36 km). One objective of this task is to extend the ca...

Ecotoxicological studies of environmental samples from Buenos Aires area using a standardized amphibian embryo toxicity test (AMPHITOX).

PubMed

Herkovits, Jorge; Perez-Coll, Cristina; Herkovits, Francisco D

2002-01-01

The toxicity of 34 environmental samples from potentially polluted and reference stations were evaluated by means of the AMPHITOX test from acute to chronic exposure according to the toxicity found in each sample. The samples were obtained from surface and ground water, leaches, industrial effluents and soils. The data, expressed in acute, short-term chronic and chronic Toxicity Units (TUa, TUstc and TUc) resulted in a maximal value of 1000 TUc, found in a leach, while the lower toxicity value was 1.4 TUa corresponding to two surface water samples. In five samples (four providing from reference places) no toxicity was detected. The results point out the possibility of evaluating the toxicity of a wide diversity of samples by means of AMPHITOX as a customized toxicity test. The fact that almost all samples with suspected toxicity in rivers and streams from the Metropolitan area of Buenos Aires city resulted toxic, indicates the need of enhanced stewardship of chemical substances for environmental and human health protection purposes.

GIS Modeling of Air Toxics Releases from TRI-Reporting and Non-TRI-Reporting Facilities: Impacts for Environmental Justice

PubMed Central

Dolinoy, Dana C.; Miranda, Marie Lynn

2004-01-01

The Toxics Release Inventory (TRI) requires facilities with 10 or more full-time employees that process > 25,000 pounds in aggregate or use > 10,000 pounds of any one TRI chemical to report releases annually. However, little is known about releases from non-TRI-reporting facilities, nor has attention been given to the very localized equity impacts associated with air toxics releases. Using geographic information systems and industrial source complex dispersion modeling, we developed methods for characterizing air releases from TRI-reporting as well as non-TRI-reporting facilities at four levels of geographic resolution. We characterized the spatial distribution and concentration of air releases from one representative industry in Durham County, North Carolina (USA). Inclusive modeling of all facilities rather than modeling of TRI sites alone significantly alters the magnitude and spatial distribution of modeled air concentrations. Modeling exposure receptors at more refined levels of geographic resolution reveals localized, neighborhood-level exposure hot spots that are not apparent at coarser geographic scales. Multivariate analysis indicates that inclusive facility modeling at fine levels of geographic resolution reveals exposure disparities by income and race. These new methods significantly enhance the ability to model air toxics, perform equity analysis, and clarify conflicts in the literature regarding environmental justice findings. This work has substantial implications for how to structure TRI reporting requirements, as well as methods and types of analysis that will successfully elucidate the spatial distribution of exposure potentials across geographic, income, and racial lines. PMID:15579419

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

EPA Science Inventory

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...

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

EPA Science Inventory

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...

Performance Validation Approach for the GTX Air-Breathing Launch Vehicle

NASA Technical Reports Server (NTRS)

Trefny, Charles J.; Roche, Joseph M.

2002-01-01

The primary objective of the GTX effort is to determine whether or not air-breathing propulsion can enable a launch vehicle to achieve orbit in a single stage. Structural weight, vehicle aerodynamics, and propulsion performance must be accurately known over the entire flight trajectory in order to make a credible assessment. Structural, aerodynamic, and propulsion parameters are strongly interdependent, which necessitates a system approach to design, evaluation, and optimization of a single-stage-to-orbit concept. The GTX reference vehicle serves this purpose, by allowing design, development, and validation of components and subsystems in a system context. The reference vehicle configuration (including propulsion) was carefully chosen so as to provide high potential for structural and volumetric efficiency, and to allow the high specific impulse of air-breathing propulsion cycles to be exploited. Minor evolution of the configuration has occurred as analytical and experimental results have become available. With this development process comes increasing validation of the weight and performance levels used in system performance determination. This paper presents an overview of the GTX reference vehicle and the approach to its performance validation. Subscale test rigs and numerical studies used to develop and validate component performance levels and unit structural weights are outlined. The sensitivity of the equivalent, effective specific impulse to key propulsion component efficiencies is presented. The role of flight demonstration in development and validation is discussed.

The Air Force Officer Qualifying Test: Validity, Fairness, and Bias

DTIC Science & Technology

2010-01-01

scores. The Standards for Educational and Psychological Testing (AERA, APA, and NCME, 1999) provides a set of guidelines published and endorsed by the...determining the validity and bias of selection tests falls upon professionals in the discipline of industrial/organizational psychology 20 See Roper v. Dep’t...i). 30 The Air Force Officer Qualifying Test : Validity, Fairness, and Bias and closely related fields (e.g., educational psychology and

FURTHER REFINEMENTS AND TESTING OF APEX3.0: EPA'S POPULATION EXPOSURE MODEL FOR CRITERIA AND AIR TOXIC INHALATION

EPA Science Inventory

The Air Pollutants Exposure Model (APEX(3.0)) is a PC-based model that was derived from the probabilistic NAAQS Exposure Model for carbon monoxide (pNEM/CO). APEX will be one of the tools used to estimate human population exposure for criteria and air toxic pollutants as part ...

In-Trail Procedure Air Traffic Control Procedures Validation Simulation Study

NASA Technical Reports Server (NTRS)

Chartrand, Ryan C.; Hewitt, Katrin P.; Sweeney, Peter B.; Graff, Thomas J.; Jones, Kenneth M.

2012-01-01

In August 2007, Airservices Australia (Airservices) and the United States National Aeronautics and Space Administration (NASA) conducted a validation experiment of the air traffic control (ATC) procedures associated with the Automatic Dependant Surveillance-Broadcast (ADS-B) In-Trail Procedure (ITP). ITP is an Airborne Traffic Situation Awareness (ATSA) application designed for near-term use in procedural airspace in which ADS-B data are used to facilitate climb and descent maneuvers. NASA and Airservices conducted the experiment in Airservices simulator in Melbourne, Australia. Twelve current operational air traffic controllers participated in the experiment, which identified aspects of the ITP that could be improved (mainly in the communication and controller approval process). Results showed that controllers viewed the ITP as valid and acceptable. This paper describes the experiment design and results.

Urban-air-toxics Monitoring Program carbonyl results, 1990

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-07-01

The report summarizes the results of sampling ambient air for selected carbonyl containing compounds in 12 urban centers in the contiguous United States as part of the Urban Air Toxics Monitoring Program (UATMP). Formaldehyde, acetaldehyde, and acetone concentrations were measured using 2,4-dinitrophenylhydrazine (DNPH)-coated silica cartridges to collect the carbonyls for subsequent analysis. Sampling and analysis followed guidance provided in U.S. Environmental Protection Agency (EPA) compendium method TO-11. Formaldehyde concentrations ranged from 0.42 to 34.5 ppbv with an average concentration for all sites of 4.2 ppbv. Site average formaldehyde concentrations ranged from 1.5 ppbv for Houston, TX (H1TX) to 7.9 formore » Washington, DC (W2DC). Acetaldehyde concentrations ranged from 0.37 to 9.5 ppbv, averaging 1.7 ppbv over all 1990 UATMP sites. Site average acetaldehyde concentrations ranged from 0.76 ppbv at Houston, TX (H1TX) to 2.5 ppbv at Baton Rouge, LA (BRLA). Acetone concentrations ranged from 0.37 to 10.8 ppbv and averaged 1.8 ppbv over all sites. Site average acetone concentrations ranged from 0.68 ppbv at Houston, TX (H1TX) to 2.9 ppbv at Chicago, IL (C4IL).« less

Validation of AIRS/AMSU Cloud Retrievals Using MODIS Cloud Analyses

NASA Technical Reports Server (NTRS)

Molnar, Gyula I.; Susskind, Joel

2005-01-01

The AIRS/AMSU (flying on the EOS-AQUA satellite) sounding retrieval methodology allows for the retrieval of key atmospheric/surface parameters under partially cloudy conditions (Susskind et al.). In addition, cloud parameters are also derived from the AIRS/AMSU observations. Within each AIRS footprint, cloud parameters at up to 2 cloud layers are determined with differing cloud top pressures and effective (product of infrared emissivity at 11 microns and physical cloud fraction) cloud fractions. However, so far the AIRS cloud product has not been rigorously evaluated/validated. Fortunately, collocated/coincident radiances measured by MODIS/AQUA (at a much lower spectral resolution but roughly an order of-magnitude higher spatial resolution than that of AIRS) are used to determine analogous cloud products from MODIS. This allows us for a rather rare and interesting possibility: the intercomparisons and mutual validation of imager vs. sounder-based cloud products obtained from the same satellite positions. First, we present results of small-scale (granules) instantaneous intercomparisons. Next, we will evaluate differences of temporally averaged (monthly) means as well as the representation of inter-annual variability of cloud parameters as presented by the two cloud data sets. In particular, we present statistical differences in the retrieved parameters of cloud fraction and cloud top pressure. We will investigate what type of cloud systems are retrieved most consistently (if any) with both retrieval schemes, and attempt to assess reasons behind statistically significant differences.

COMPENDIUM OF METHODS FOR THE DETERMINATION OF TOXIC ORGANIC COMPOUNDS IN AMBIENT AIR--SECOND EDITION

EPA Science Inventory

This Second Edition of the Compendium has been prepared to provide regional, state and local environmental regulatory agencies with step-by-step sampling and analysis procedures for the determination of selected toxic organic pollutants in ambient air. It is designed to assist t...

LINKING AIR TOXIC CONCENTRATIONS FROM CMAQ TO THE HAPEM5 EXPOSURE MODEL AT NEIGHORHOOD SCALES FOR THE PHILADELPHIA AREA

EPA Science Inventory

This paper provides a preliminary demonstration of the EPA neighborhood scale modeling paradigm for air toxics by linking concentration from the Community Multi-scale Air Quality (CMAQ) modeling system to the fifth version of the Hazardous Pollutant Exposure Model (HAPEM5). For ...

Hanging drop: an in vitro air toxic exposure model using human lung cells in 2D and 3D structures.

PubMed

Liu, Faye F; Peng, Cheng; Escher, Beate I; Fantino, Emmanuelle; Giles, Cindy; Were, Stephen; Duffy, Lesley; Ng, Jack C

2013-10-15

Using benzene as a candidate air toxicant and A549 cells as an in vitro cell model, we have developed and validated a hanging drop (HD) air exposure system that mimics an air liquid interface exposure to the lung for periods of 1h to over 20 days. Dose response curves were highly reproducible for 2D cultures but more variable for 3D cultures. By comparing the HD exposure method with other classically used air exposure systems, we found that the HD exposure method is more sensitive, more reliable and cheaper to run than medium diffusion methods and the CULTEX(®) system. The concentration causing 50% of reduction of cell viability (EC50) for benzene, toluene, p-xylene, m-xylene and o-xylene to A549 cells for 1h exposure in the HD system were similar to previous in vitro static air exposure. Not only cell viability could be assessed but also sub lethal biological endpoints such as DNA damage and interleukin expressions. An advantage of the HD exposure system is that bioavailability and cell concentrations can be derived from published physicochemical properties using a four compartment mass balance model. The modelled cellular effect concentrations EC50cell for 1h exposure were very similar for benzene, toluene and three xylenes and ranged from 5 to 15 mmol/kgdry weight, which corresponds to the intracellular concentration of narcotic chemicals in many aquatic species, confirming the high sensitivity of this exposure method. Copyright © 2013 Elsevier B.V. All rights reserved.

Air-braked cycle ergometers: validity of the correction factor for barometric pressure.

PubMed

Finn, J P; Maxwell, B F; Withers, R T

2000-10-01

Barometric pressure exerts by far the greatest influence of the three environmental factors (barometric pressure, temperature and humidity) on power outputs from air-braked ergometers. The barometric pressure correction factor for power outputs from air-braked ergometers is in widespread use but apparently has never been empirically validated. Our experiment validated this correction factor by calibrating two air-braked cycle ergometers in a hypobaric chamber using a dynamic calibration rig. The results showed that if the power output correction for changes in air resistance at barometric pressures corresponding to altitudes of 38, 600, 1,200 and 1,800 m above mean sea level were applied, then the coefficients of variation were 0.8-1.9% over the range of 160-1,597 W. The overall mean error was 3.0 % but this included up to 0.73 % for the propagated error that was associated with errors in the measurement of: a) temperature b) relative humidity c) barometric pressure d) force, distance and angular velocity by the dynamic calibration rig. The overall mean error therefore approximated the +/- 2.0% of true load that was specified by the Laboratory Standards Assistance Scheme of the Australian Sports Commission. The validity of the correction factor for barometric pressure on power output was therefore demonstrated over the altitude range of 38-1,800 m.

Thermal Stress and Toxicity

EPA Science Inventory

Elevating ambient temperature above thermoneutrality exacerbates toxicity of most air pollutants, insecticides, and other toxic chemicals. On the other hand, safety and toxicity testing of toxicants and drugs is usually performed in mice and rats maintained at subthermoneutral te...

Validating the AIRS Version 5 CO Retrieval with DACOM In Situ Measurements During INTEX-A and -B

NASA Technical Reports Server (NTRS)

McMillan, Wallace W.; Evans, Keith D.; Barnet, Christopher D.; Maddy, Eric; Sachse, Glen W.; Diskin, Glenn S.

2011-01-01

Herein we provide a description of the atmospheric infrared sounder (AIRS) version 5 (v5) carbon monoxide (CO) retrieval algorithm and its validation with the DACOM in situ measurements during the INTEX-A and -B campaigns. All standard and support products in the AIRS v5 CO retrieval algorithm are documented. Building on prior publications, we describe the convolution of in situ measurements with the AIRS v5 CO averaging kernel and first-guess CO profile as required for proper validation. Validation is accomplished through comparison of AIRS CO retrievals with convolved in situ CO profiles acquired during the NASA Intercontinental Chemical Transport Experiments (INTEX) in 2004 and 2006. From 143 profiles in the northern mid-latitudes during these two experiments, we find AIRS v5 CO retrievals are biased high by 6% 10% between 900 and 300 hPa with a root-mean-square error of 8% 12%. No significant differences were found between validation using spiral profiles coincident with AIRS overpasses and in-transit profiles under the satellite track but up to 13 h off in time. Similarly, no significant differences in validation results were found for ocean versus land, day versus night, or with respect to retrieved cloud top pressure or cloud fraction.

PARAMETRIC EVALUATION OF VOC/HAP (VOLATILE ORGANIC COMPOUNDS-HAZARDOUS/TOXIC AIR POLLUTANTS) DESTRUCTION VIA CATALYTIC INCINERATION

EPA Science Inventory

The report describes the use of a pilot-scale catalytic incineration unit/solvent generation system to investigate the effectiveness of catalytic incineration as a way to destroy volatile organic compounds (VOCs) and hazardous/toxic air pollutants (HAPs). Objectives of the study ...

The Air Force Officer Qualifying Test: Validity, Fairness, and Bias. Technical Report

ERIC Educational Resources Information Center

Hardison, Chaitra M.; Sims, Carra S.; Wong, Eunice C.

2010-01-01

The Air Force has long recognized the importance of selecting the most qualified officers possible. For more than 60 years, it has relied on the Air Force Officer Qualifying Test (AFOQT) as one measure of those qualifications. A variety of concerns have been raised about whether the AFOQT is biased, too expensive, or even valid for predicting…

PRELIMINARY FINDINGS ON THE ASSESSMENT OF POTENTIAL CAR-RELATED OCCUPATIONAL PM AND AIR TOXIC EXPOSURE TO PATROL TROOPERS (COPP STUDY)

EPA Science Inventory

In-vehicle, roadside and community-based measurements of particulate matter (PM) and select air toxics were measured as part of a study involving patrol cars from the North Carolina Highway Patrol. One goal of this study was to characterize PM and related air pollutant concentra...

Reduced Toxicity, High Performance Monopropellant at the U.S. Air Force Research Laboratory

NASA Astrophysics Data System (ADS)

Hawkins, T. W.; Brand, A. J.; McKay, M. B.; Tinnirello, M.

2010-09-01

Current programs are aiming to develop reduced toxicity monopropellant formulations to replace spacecraft hydrazine monopropellant. The Air Force Research Laboratory's(AFRL's) approach to replacing hydrazine is the synthesis and development of energetic compounds/formulations with substantially less vapor toxicity and superior performance(specific impulse and density). Characterization and testing of these high energy density materials is an essential part of the screening process for viable advanced propellants. Hazardous handling characteristics, undesirable physical properties or unacceptable sensitivity behaviors must also be identified and/or modified to further development by a potential user. AFRL has successfully identified a novel monopropellant(designated AF-M315E) that shows great promise as an avenue toward replacement of hydrazine monopropellant for spacecraft propulsion. Hazard and safety/sensitivity, stability, and toxicity studies have been conducted on the monopropellant and will be described. The results from AF-M315E indicate that a >50% improvement in propulsion system performance over hydrazine is achievable while simultaneously providing a safer environment for the general public, ground personnel, crews and flight participants.

Air Toxics Emissions from Open Burning of Crop Residues in Southeast Asia

NASA Astrophysics Data System (ADS)

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.

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

PubMed

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.

Validity of clinical color vision tests for air traffic control specialists.

DOT National Transportation Integrated Search

1992-10-01

An experiment on the relationship between aeromedical color vision screening test performance and performance on color-dependent tasks of Air Traffic Control Specialists was replicated to expand the data base supporting the job-related validity of th...

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

PubMed

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.

Development and Validation of a Supersonic Helium-Air Coannular Jet Facility

NASA Technical Reports Server (NTRS)

Carty, Atherton A.; Cutler, Andrew D.

1999-01-01

Data are acquired in a simple coannular He/air supersonic jet suitable for validation of CFD (Computational Fluid Dynamics) codes for high speed propulsion. Helium is employed as a non-reacting hydrogen fuel simulant, constituting the core of the coannular flow while the coflow is composed of air. The mixing layer interface between the two flows in the near field and the plume region which develops further downstream constitute the primary regions of interest, similar to those present in all hypersonic air breathing propulsion systems. A computational code has been implemented from the experiment's inception, serving as a tool for model design during the development phase.

Perspectives on Validation of High-Throughput Assays Supporting 21st Century Toxicity Testing1

PubMed Central

Judson, Richard; Kavlock, Robert; Martin, Matt; Reif, David; Houck, Keith; Knudsen, Thomas; Richard, Ann; Tice, Raymond R.; Whelan, Maurice; Xia, Menghang; Huang, Ruili; Austin, Christopher; Daston, George; Hartung, Thomas; Fowle, John R.; Wooge, William; Tong, Weida; Dix, David

2014-01-01

Summary In vitro, high-throughput screening (HTS) assays are seeing increasing use in toxicity testing. HTS assays can simultaneously test many chemicals, but have seen limited use in the regulatory arena, in part because of the need to undergo rigorous, time-consuming formal validation. Here we discuss streamlining the validation process, specifically for prioritization applications in which HTS assays are used to identify a high-concern subset of a collection of chemicals. The high-concern chemicals could then be tested sooner rather than later in standard guideline bioassays. The streamlined validation process would continue to ensure the reliability and relevance of assays for this application. We discuss the following practical guidelines: (1) follow current validation practice to the extent possible and practical; (2) make increased use of reference compounds to better demonstrate assay reliability and relevance; (3) deemphasize the need for cross-laboratory testing, and; (4) implement a web-based, transparent and expedited peer review process. PMID:23338806

Spatial variations of particulate matter and air toxics in communities adjacent to the Port of Oakland.

PubMed

Fujita, Eric M; Campbell, David E; Arnott, W Patrick; Lau, Virginia; Martien, Philip T

2013-12-01

The Bay Area Air Quality Management District (BAAQMD) sponsored the West Oakland Monitoring Study (WOMS) to provide supplemental air quality monitoring that will be used by the BAAQMD to evaluate local-scale dispersion modeling of diesel emissions and other toxic air contaminants for the area within and around the Port of Oakland. The WOMS was conducted during two seasonal periods of 4 weeks in summer 2009 and winter 2009/2010. Monitoring data showed spatial patterns of pollutant concentrations that were generally consistent with proximity to vehicle traffic. Concentrations of directly emitted pollutants were highest on heavily traveled roads with consistently lower concentrations away from the roadways. Pollutants that have higher emission rates from diesel trucks (nitric oxide, black carbon) tended to exhibit sharper gradients than pollutants that are largely associated with gasoline vehicles, such as carbon monoxide and volatile organic compounds, including benzene, toluene, ethylbenzene, and xylenes (BTEX). BTEX concentrations in West Oakland were similar to those measured at the three air toxics monitoring network sites in the Bay Area (San Francisco, Fremont, and San Jose). Aldehyde levels were higher in Fremont and San Jose than in West Oakland, reflecting greater contributions from photo-oxidation of hydrocarbons downwind of the Bay Area. A 2005 modeling-based health risk assessment of diesel particulate matter concentrations is consistent with aerosol carbon concentrations measured during the WOMS after adjusting for recent mitigation measures and improved estimates of heavy-duty truck traffic volumes.

In vitro toxicity testing of cigarette smoke based on the air-liquid interface exposure: A review.

PubMed

Li, Xiang

2016-10-01

Cigarette smoke is a complex aerosol comprising particulate phase and gaseous vapour phase. The air-liquid interface exposure provides a possible technical means to implement whole smoke exposure for the assessment of tobacco products. In this review, the research progress in the in vitro toxicity testing of cigarette smoke based on the air-liquid interface exposure is summarized. The contents presented involve mainly cytotoxicity, genotoxicity, oxidative stress, inflammation, systems toxicology, 3D culture and cigarette smoke dosimetry related to cigarette smoke, as well as the assessment of electronic cigarette aerosol. Prospect of the application of the air-liquid interface exposure method in assessing the biological effects of tobacco smoke is discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Quantitative dose-response assessment of inhalation exposures to toxic air pollutants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jarabek, A.M.; Foureman, G.L.; Gift, J.S.

1997-12-31

Implementation of the 1990 Clean Air Act Amendments, including evaluation of residual risks. requires accurate human health risk estimates of both acute and chronic inhalation exposures to toxic air pollutants. The U.S. Environmental Protection Agency`s National Center for Environmental Assessment, Research Triangle Park, NC, has a research program that addresses several key issues for development of improved quantitative approaches for dose-response assessment. This paper describes three projects underway in the program. Project A describes a Bayesian approach that was developed to base dose-response estimates on combined data sets and that expresses these estimates as probability density functions. A categorical regressionmore » model has been developed that allows for the combination of all available acute data, with toxicity expressed as severity categories (e.g., mild, moderate, severe), and with both duration and concentration as governing factors. Project C encompasses two refinements to uncertainty factors (UFs) often applied to extrapolate dose-response estimates from laboratory animal data to human equivalent concentrations. Traditional UFs have been based on analyses of oral administration and may not be appropriate for extrapolation of inhalation exposures. Refinement of the UF applied to account for the use of subchronic rather than chronic data was based on an analysis of data from inhalation exposures (Project C-1). Mathematical modeling using the BMD approach was used to calculate the dose-response estimates for comparison between the subchronic and chronic data so that the estimates were not subject to dose-spacing or sample size variability. The second UF that was refined for extrapolation of inhalation data was the adjustment for the use of a LOAEL rather than a NOAEL (Project C-2).« less

Air Combat Training: Good Stick Index Validation. Final Report for Period 3 April 1978-1 April 1979.

ERIC Educational Resources Information Center

Moore, Samuel B.; And Others

A study was conducted to investigate and statistically validate a performance measuring system (the Good Stick Index) in the Tactical Air Command Combat Engagement Simulator I (TAC ACES I) Air Combat Maneuvering (ACM) training program. The study utilized a twelve-week sample of eighty-nine student pilots to statistically validate the Good Stick…

Air Toxics under the Big Sky: A Real-World Investigation to Engage High School Science Students

ERIC Educational Resources Information Center

Adams, Earle; Smith, Garon; Ward, Tony J.; Vanek, Diana; Marra, Nancy; Jones, David; Henthorn, Melissa; Striebel, Jim

2008-01-01

This paper describes a problem-based chemistry education model in which students perform scientific research on a local environmentally relevant problem. The project is a collaboration among The University of Montana and local high schools centered around Missoula, Montana. "Air Toxics under the Big Sky" involves high school students in collecting…

Significant Association of Urinary Toxic Metals and Autism-Related Symptoms—A Nonlinear Statistical Analysis with Cross Validation

PubMed Central

Adams, James; Kruger, Uwe; Geis, Elizabeth; Gehn, Eva; Fimbres, Valeria; Pollard, Elena; Mitchell, Jessica; Ingram, Julie; Hellmers, Robert; Quig, David; Hahn, Juergen

2017-01-01

Introduction A number of previous studies examined a possible association of toxic metals and autism, and over half of those studies suggest that toxic metal levels are different in individuals with Autism Spectrum Disorders (ASD). Additionally, several studies found that those levels correlate with the severity of ASD. Methods In order to further investigate these points, this paper performs the most detailed statistical analysis to date of a data set in this field. First morning urine samples were collected from 67 children and adults with ASD and 50 neurotypical controls of similar age and gender. The samples were analyzed to determine the levels of 10 urinary toxic metals (UTM). Autism-related symptoms were assessed with eleven behavioral measures. Statistical analysis was used to distinguish participants on the ASD spectrum and neurotypical participants based upon the UTM data alone. The analysis also included examining the association of autism severity with toxic metal excretion data using linear and nonlinear analysis. “Leave-one-out” cross-validation was used to ensure statistical independence of results. Results and Discussion Average excretion levels of several toxic metals (lead, tin, thallium, antimony) were significantly higher in the ASD group. However, ASD classification using univariate statistics proved difficult due to large variability, but nonlinear multivariate statistical analysis significantly improved ASD classification with Type I/II errors of 15% and 18%, respectively. These results clearly indicate that the urinary toxic metal excretion profiles of participants in the ASD group were significantly different from those of the neurotypical participants. Similarly, nonlinear methods determined a significantly stronger association between the behavioral measures and toxic metal excretion. The association was strongest for the Aberrant Behavior Checklist (including subscales on Irritability, Stereotypy, Hyperactivity, and Inappropriate

Multisensor system for toxic gases detection generated on indoor environments

NASA Astrophysics Data System (ADS)

Durán, C. M.; Monsalve, P. A. G.; Mosquera, C. J.

2016-11-01

This work describes a wireless multisensory system for different toxic gases detection generated on indoor environments (i.e., Underground coal mines, etc.). The artificial multisensory system proposed in this study was developed through a set of six chemical gas sensors (MQ) of low cost with overlapping sensitivities to detect hazardous gases in the air. A statistical parameter was implemented to the data set and two pattern recognition methods such as Principal Component Analysis (PCA) and Discriminant Function Analysis (DFA) were used for feature selection. The toxic gases categories were classified with a Probabilistic Neural Network (PNN) in order to validate the results previously obtained. The tests were carried out to verify feasibility of the application through a wireless communication model which allowed to monitor and store the information of the sensor signals for the appropriate analysis. The success rate in the measures discrimination was 100%, using an artificial neural network where leave-one-out was used as cross validation method.

"Air Toxics under the Big Sky": Examining the Effectiveness of Authentic Scientific Research on High School Students' Science Skills and Interest

ERIC Educational Resources Information Center

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)…

Defences against ammonia toxicity in tropical air-breathing fishes exposed to high concentrations of environmental ammonia: a review.

PubMed

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.

Inhalation toxicity of indoor air pollutants in Drosophila melanogaster using integrated transcriptomics and computational behavior analyses

NASA Astrophysics Data System (ADS)

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.

Inhalation toxicity of indoor air pollutants in Drosophila melanogaster using integrated transcriptomics and computational behavior analyses

PubMed Central

Eom, Hyun-Jeong; Liu, Yuedan; Kwak, Gyu-Suk; Heo, Muyoung; Song, Kyung Seuk; Chung, Yun Doo; Chon, Tae-Soo; Choi, Jinhee

2017-01-01

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. PMID:28621308

Portable air pollution control equipment for the control of toxic particulate emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chaurushia, A.; Odabashian, S.; Busch, E.

1997-12-31

Chromium VI (Cr VI) has been identified by the environmental regulatory agencies as a potent carcinogen among eleven heavy metals. A threshold level of 0.0001 lb/year for Cr VI emissions has been established by the California Air Resources Board for reporting under Assembly Bill 2588. A need for an innovative control technology to reduce fugitive emissions of Cr VI was identified during the Air Toxic Emissions Reduction Program at Northrop Grumman Military Aircraft Systems Division (NGMASD). NGMASD operates an aircraft assembly facility in El Segundo, CA. Nearly all of the aircraft components are coated with a protective coating (primer) priormore » to assembly. The primer has Cr VI as a component for its excellent corrosion resistance property. The complex assembly process requires fasteners which also need primer coating. Therefore, NGMASD utilizes High Volume Low Pressure (HVLP) guns for the touch-up spray coating operations. During the touch-up spray coating operations, Cr VI particles are atomized and transferred to the aircraft surface. The South Coast Air Quality Management District (SCAQMD) has determined that the HVLP gun transfers 65% of the paint particles onto the substrate and the remaining 35% are emitted as an overspray if air pollution controls are not applied. NGMASD has developed the Portable Air Pollution Control Equipment (PAPCE) to capture and control the overspray in order to reduce fugitive Cr VI emissions from the touch-up spray coating operations. A source test was performed per SCAQMD guidelines and the final report has been approved by the SCAQMD.« less

Toxicity and bioconcentration of hexachlorocyclohexane (HCH) in an air-breathing catfish, Saccobranchus fossilis (Bloch)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khangarot, B.S.; Takroo, R.; Singh, R.R.

1991-12-01

The current study was undertaken to determine the sublethal toxicity of commercial grade hexachlorocyclohexane (HCH) to a freshwater air-breathing catfish, Saccobranchus fossilis (Bloch) for 14 days. The bioconcentration of HCH and its distribution in gill, brain and liver was determined. This species was selected for the present study because it is widely distributed in ponds, lakes and rivers of India and consumed as human diet in many parts of the world.

40 CFR 80.915 - How are the baseline toxics value and baseline toxics volume determined?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false How are the baseline toxics value and... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Baseline Determination § 80.915 How are the baseline toxics value and baseline toxics volume determined? (a...

40 CFR 80.915 - How are the baseline toxics value and baseline toxics volume determined?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 16 2011-07-01 2011-07-01 false How are the baseline toxics value and... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Baseline Determination § 80.915 How are the baseline toxics value and baseline toxics volume determined? (a...

Survey of statistical techniques used in validation studies of air pollution prediction models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bornstein, R D; Anderson, S F

1979-03-01

Statistical techniques used by meteorologists to validate predictions made by air pollution models are surveyed. Techniques are divided into the following three groups: graphical, tabular, and summary statistics. Some of the practical problems associated with verification are also discussed. Characteristics desired in any validation program are listed and a suggested combination of techniques that possesses many of these characteristics is presented.

Validation of AIRS Retrievals of CO2 via Comparison to In Situ Measurements

NASA Technical Reports Server (NTRS)

Olsen, Edward T.; Chahine, Moustafa T.; Chen, Luke L.; Jiang, Xun; Pagano, Thomas S.; Yung, Yuk L.

2008-01-01

Topics include AIRS on Aqua, 2002-present with discussion about continued operation to 2011 and beyond and background, including spectrum, weighting functions, and initialization; comparison with aircraft and FTIR measurements in Masueda (CONTRAIL) JAL flask measurements, Park Falls, WI FTIR, Bremen, GDF, and Spitsbergen, Norway; AIRS retrievals over addition FTIR sites in Darwin, AU and Lauder, NZ; and mid-tropospheric carbon dioxide weather and contribution from major surface sources. Slide titles include typical AIRS infrared spectrum, AIRS sensitivity for retrieving CO2 profiles, independence of CO2 solution with respect to the initial guess, available in situ measurements for validation and comparison, comparison of collocated V1.5x AIRS CO2 (N_coll greater than or equal to 9) with INTEX-NA and SPURT;

PREVENTION REFERENCE MANUAL: CONTROL TECHNOLOGIES, VOL. 2. POST-RELEASE MITIGATION MEASURES FOR CONTROLLING ACCIDENTAL RELEASES OF AIR TOXICS

EPA Science Inventory

The volume discusses prevention and protection measures for controlling accidental releases of air toxics. The probability of accidental releases depends on the extent to which deviations (in magnitude and duration) in the process can be tolerated before a loss of chemical contai...

Validation of the Atmospheric Infrared Sounder (AIRS) over the Antarctic Plateau: Low Radiance, Low Humidity, and Thin Clouds

NASA Technical Reports Server (NTRS)

Tobin, David C.

2005-01-01

The main goal of the project has been to use specialized measurements collected at the Antarctic Plateau to provide validation of the Atmospheric InfraRed Sounder (AIRS) spectral radiances and some AIRS Level 2 products. As proposed, efforts conducted at the University of Wisconsin are focused on providing technical information, data, and software in support of the validation studies.

Toxicity of copper oxide nanoparticles in lung epithelial cells exposed at the air-liquid interface compared with in vivo assessment.

PubMed

Jing, Xuefang; Park, Jae Hong; Peters, Thomas M; Thorne, Peter S

2015-04-01

The toxicity of spark-generated copper oxide nanoparticles (CuONPs) was evaluated in human bronchial epithelial cells (HBEC) and lung adenocarcinoma cells (A549 cells) using an in vitro air-liquid interface (ALI) exposure system. Dose-response results were compared to in vivo inhalation and instillation studies of CuONPs. Cells were exposed to filtered, particle-free clean air (controls) or spark-generated CuONPs. The number median diameter, geometric standard deviation and total number concentration of CuONPs were 9.2 nm, 1.48 and 2.27×10(7)particles/cm(3), respectively. Outcome measures included cell viability, cytotoxicity, oxidative stress and proinflammatory chemokine production. Exposure to clean air (2 or 4h) did not induce toxicity in HBEC or A549 cells. Compared with controls, CuONP exposures significantly reduced cell viability, increased lactate dehydrogenase (LDH) release and elevated levels of reactive oxygen species (ROS) and IL-8 in a dose-dependent manner. A549 cells were significantly more susceptible to CuONP effects than HBEC. Antioxidant treatment reduced CuONP-induced cytotoxicity. When dose was expressed per area of exposed epithelium there was good agreement of toxicity measures with murine in vivo studies. This demonstrates that in vitro ALI studies can provide meaningful data on nanotoxicity of metal oxides. Copyright © 2015 Elsevier Ltd. All rights reserved.

Incremental Validity of Biographical Data in the Prediction of En Route Air Traffic Control Specialist Technical Skills

DTIC Science & Technology

2012-07-01

Incremental Validity of Biographical Data in the Prediction of En Route Air Traffic Control Specialist Technical Skills Dana Broach Civil Aerospace...Medical Institute Federal Aviation Administration Oklahoma City, OK 73125 July 2012 Final Report DOT/FAA/AM- 12 /8 Office of Aerospace Medicine...FAA/AM- 12 /8 4. Title and Subtitle 5. Report Date July 2012 Incremental Validity of Biographical Data in the Prediction of En Route Air

Understanding environmental health inequalities through comparative intracategorical analysis: racial/ethnic disparities in cancer risks from air toxics in El Paso County, Texas.

PubMed

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.

Hazardous Air Pollutants

MedlinePlus

... Air Toxics Website Rules and Implementation Related Information Air Quality Data and Tools Clean Air Act Criteria Air ... Resources Visibility and Haze Voluntary Programs for Improving Air Quality Contact Us to ask a question, provide feedback, ...

Global Validation of MODIS Atmospheric Profile-Derived Near-Surface Air Temperature and Dew Point Estimates

NASA Astrophysics Data System (ADS)

Famiglietti, C.; Fisher, J.; Halverson, G. H.

2017-12-01

This study validates a method of remote sensing near-surface meteorology that vertically interpolates MODIS atmospheric profiles to surface pressure level. The extraction of air temperature and dew point observations at a two-meter reference height from 2001 to 2014 yields global moderate- to fine-resolution near-surface temperature distributions that are compared to geographically and temporally corresponding measurements from 114 ground meteorological stations distributed worldwide. This analysis is the first robust, large-scale validation of the MODIS-derived near-surface air temperature and dew point estimates, both of which serve as key inputs in models of energy, water, and carbon exchange between the land surface and the atmosphere. Results show strong linear correlations between remotely sensed and in-situ near-surface air temperature measurements (R2 = 0.89), as well as between dew point observations (R2 = 0.77). Performance is relatively uniform across climate zones. The extension of mean climate-wise percent errors to the entire remote sensing dataset allows for the determination of MODIS air temperature and dew point uncertainties on a global scale.

Validation of the Federal Aviation Administration Air Traffic Control Specialist Pre-Training Screen.

DOT National Transportation Integrated Search

1994-02-01

Two formal validation studies of the Air Traffic Control Specialist Pre Training Screen (ATCS/PTS), a 5 day computer administered test battery, are described. The ATCS/PTS was designed to replace the 9 week US Federal Aviation Administration (FAA) Ac...

Occurrence and Concentrations of Toxic VOCs in the Ambient Air of Gumi, an Electronics-Industrial City in Korea.

PubMed

Baek, Sung-Ok; Suvarapu, Lakshmi Narayana; Seo, Young-Kyo

2015-08-05

This study was carried out to characterize the occurrence and concentrations of a variety of volatile organic compounds (VOCs) including aliphatic, aromatic, halogenated, nitrogenous, and carbonyl compounds, in the ambient air of Gumi City, where a large number of electronics industries are found. Two field monitoring campaigns were conducted for a one year period in 2003/2004 and 2010/2011 at several sampling sites in the city, representing industrial, residential and commercial areas. More than 80 individual compounds were determined in this study, and important compounds were then identified according to their abundance, ubiquity and toxicity. The monitoring data revealed toluene, trichloroethylene and acetaldehyde to be the most significant air toxics in the city, and their major sources were mainly industrial activities. On the other hand, there was no clear evidence of an industrial impact on the concentrations of benzene and formaldehyde in the ambient air of the city. Overall, seasonal variations were not as distinct as locational variations in the VOCs concentrations, whereas the within-day variations showed a typical pattern of urban air pollution, i.e., increase in the morning, decrease in the afternoon, and an increase again in the evening. Considerable decreases in the concentrations of VOCs from 2003 to 2011 were observed. The reductions in the ambient concentrations were confirmed further by the Korean PRTR data in industrial emissions within the city. Significant decreases in the concentrations of benzene and acetaldehyde were also noted, whereas formaldehyde appeared to be almost constant between the both campaigns. The decreased trends in the ambient levels were attributed not only to the stricter regulations for VOCs in Korea, but also to the voluntary agreement of major companies to reduce the use of organic solvents. In addition, a site planning project for an eco-friendly industrial complex is believed to play a contributory role in improving

Presence of organophosphorus pesticide oxygen analogs in air samples

NASA Astrophysics Data System (ADS)

Armstrong, Jenna L.; Fenske, Richard A.; Yost, Michael G.; Galvin, Kit; Tchong-French, Maria; Yu, Jianbo

2013-02-01

A number of recent toxicity studies have highlighted the increased potency of oxygen analogs (oxons) of several organophosphorus (OP) pesticides. These findings were a major concern after environmental oxons were identified in environmental samples from air and surfaces following agricultural spray applications in California and Washington State. This paper reports on the validity of oxygen analog measurements in air samples for the OP pesticide, chlorpyrifos. Controlled environmental and laboratory experiments were used to examine artificial formation of chlorpyrifos-oxon using OSHA Versatile Sampling (OVS) tubes as recommended by NIOSH method 5600. Additionally, we compared expected chlorpyrifos-oxon attributable to artificial transformation to observed chlorpyrifos-oxon in field samples from a 2008 Washington State Department of Health air monitoring study using non-parametric statistical methods. The amount of artificially transformed oxon was then modeled to determine the amount of oxon present in the environment. Toxicity equivalency factors (TEFs) for chlorpyrifos-oxon were used to calculate chlorpyrifos-equivalent air concentrations. The results demonstrate that the NIOSH-recommended sampling matrix (OVS tubes with XAD-2 resin) was found to artificially transform up to 30% of chlorpyrifos to chlorpyrifos-oxon, with higher percentages at lower concentrations (<30 ng m-3) typical of ambient or residential levels. Overall, the 2008 study data had significantly greater oxon than expected by artificial transformation, but the exact amount of environmental oxon in air remains difficult to quantify with the current sampling method. Failure to conduct laboratory analysis for chlorpyrifos-oxon may result in underestimation of total pesticide concentration when using XAD-2 resin matrices for occupational or residential sampling. Alternative methods that can accurately measure both OP pesticides and their oxygen analogs should be used for air sampling, and a toxicity

Improved Products for Assimilation and Model Validation from the Atmospheric Infrared Sounder (AIRS) on Aqua

NASA Technical Reports Server (NTRS)

Pagano, Thomas S.

2008-01-01

The Atmospheric Infrared Sounder (AIRS) on the EOS Aqua Spacecraft was launched on May 4, 2002. AIRS acquires hyperspectral infrared radiances in the 3.7-15.4 micrometer spectral region with spectral resolution of better than 1200. Key channels from the AIRS Level 1B calibrated radiance product are currently assimilated into operational weather forecasts at NCEP and other international agencies. Additional Level 2 products for assimilation include the AIRS cloud cleared radiances and the geophysical retrieved temperature and water vapor profiles. The AIRS products are also used to validate climate model vertical and horizontal biases and transport of water vapor and key trace gases including Carbon Dioxide and Ozone. The wide variety of products available from the AIRS make it well suited to study processes affecting the interaction of these products.

MONITORING THE AIR FOR TOXIC AND GENOTOXIC COMPOUNDS

EPA Science Inventory

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...

A Microfluidic Device for Continuous Sensing of Systemic Acute Toxicants in Drinking Water

PubMed Central

Zhao, Xinyan; Dong, Tao

2013-01-01

A bioluminescent-cell-based microfluidic device for sensing toxicants in drinking water was designed and fabricated. The system employed Vibrio fischeri cells as broad-spectrum sensors to monitor potential systemic cell toxicants in water, such as heavy metal ions and phenol. Specifically, the chip was designed for continuous detection. The chip design included two counter-flow micromixers, a T-junction droplet generator and six spiral microchannels. The cell suspension and water sample were introduced into the micromixers and dispersed into droplets in the air flow. This guaranteed sufficient oxygen supply for the cell sensors. Copper (Cu2+), zinc (Zn2+), potassium dichromate and 3,5-dichlorophenol were selected as typical toxicants to validate the sensing system. Preliminary tests verified that the system was an effective screening tool for acute toxicants although it could not recognize or quantify specific toxicants. A distinct non-linear relationship was observed between the zinc ion concentration and the Relative Luminescence Units (RLU) obtained during testing. Thus, the concentration of simple toxic chemicals in water can be roughly estimated by this system. The proposed device shows great promise for an early warning system for water safety. PMID:24300075

Classification of baseline toxicants for QSAR predictions to replace fish acute toxicity studies.

PubMed

Nendza, Monika; Müller, Martin; Wenzel, Andrea

2017-03-22

Fish acute toxicity studies are required for environmental hazard and risk assessment of chemicals by national and international legislations such as REACH, the regulations of plant protection products and biocidal products, or the GHS (globally harmonised system) for classification and labelling of chemicals. Alternative methods like QSARs (quantitative structure-activity relationships) can replace many ecotoxicity tests. However, complete substitution of in vivo animal tests by in silico methods may not be realistic. For the so-called baseline toxicants, it is possible to predict the fish acute toxicity with sufficient accuracy from log K ow and, hence, valid QSARs can replace in vivo testing. In contrast, excess toxicants and chemicals not reliably classified as baseline toxicants require further in silico, in vitro or in vivo assessments. Thus, the critical task is to discriminate between baseline and excess toxicants. For fish acute toxicity, we derived a scheme based on structural alerts and physicochemical property thresholds to classify chemicals as either baseline toxicants (=predictable by QSARs) or as potential excess toxicants (=not predictable by baseline QSARs). The step-wise approach identifies baseline toxicants (true negatives) in a precautionary way to avoid false negative predictions. Therefore, a certain fraction of false positives can be tolerated, i.e. baseline toxicants without specific effects that may be tested instead of predicted. Application of the classification scheme to a new heterogeneous dataset for diverse fish species results in 40% baseline toxicants, 24% excess toxicants and 36% compounds not classified. Thus, we can conclude that replacing about half of the fish acute toxicity tests by QSAR predictions is realistic to be achieved in the short-term. The long-term goals are classification criteria also for further groups of toxicants and to replace as many in vivo fish acute toxicity tests as possible with valid QSAR

Quantitative validation of an air-coupled ultrasonic probe model by Interferometric laser tomography

NASA Astrophysics Data System (ADS)

Revel, G. M.; Pandarese, G.; Cavuto, A.

2012-06-01

The present paper describes the quantitative validation of a finite element (FE) model of the ultrasound beam generated by an air coupled non-contact ultrasound transducer. The model boundary conditions are given by vibration velocities measured by laser vibrometry on the probe membrane. The proposed validation method is based on the comparison between the simulated 3D pressure field and the pressure data measured with interferometric laser tomography technique. The model details and the experimental techniques are described in paper. The analysis of results shows the effectiveness of the proposed approach and the possibility to quantitatively assess and predict the generated acoustic pressure field, with maximum discrepancies in the order of 20% due to uncertainty effects. This step is important for determining in complex problems the real applicability of air-coupled probes and for the simulation of the whole inspection procedure, also when the component is designed, so as to virtually verify its inspectability.

Validation of the Fully-Coupled Air-Sea-Wave COAMPS System

NASA Astrophysics Data System (ADS)

Smith, T.; Campbell, T. J.; Chen, S.; Gabersek, S.; Tsu, J.; Allard, R. A.

2017-12-01

A fully-coupled, air-sea-wave numerical model, COAMPS®, has been developed by the Naval Research Laboratory to further enhance understanding of oceanic, atmospheric, and wave interactions. The fully-coupled air-sea-wave system consists of an atmospheric component with full physics parameterizations, an ocean model, NCOM (Navy Coastal Ocean Model), and two wave components, SWAN (Simulating Waves Nearshore) and WaveWatch III. Air-sea interactions between the atmosphere and ocean components are accomplished through bulk flux formulations of wind stress and sensible and latent heat fluxes. Wave interactions with the ocean include the Stokes' drift, surface radiation stresses, and enhancement of the bottom drag coefficient in shallow water due to the wave orbital velocities at the bottom. In addition, NCOM surface currents are provided to SWAN and WaveWatch III to simulate wave-current interaction. The fully-coupled COAMPS system was executed for several regions at both regional and coastal scales for the entire year of 2015, including the U.S. East Coast, Western Pacific, and Hawaii. Validation of COAMPS® includes observational data comparisons and evaluating operational performance on the High Performance Computing (HPC) system for each of these regions.

1990 Clean Air Act Amendment Summary: Title III

EPA Pesticide Factsheets

This page provides an overview of the 1990 amendments to Title III of the Clean Air Act, which were enacted to curb acid rain, urban air pollution and toxic air emissions. The edits to this title deal with toxic air pollutants.

Toxic air pollution across a state line: implications for the siting of resource recovery facilities.

PubMed

Landrigan, P J; Halper, L A; Silbergeld, E K

1989-01-01

Massive volumes of solid waste are produced in the United States. Options for disposal are limited. Incineration and recycling are frequently proposed solutions. However, incinerators and waste recovery facilities, such as scrap smelters, generate hazardous air pollutants and toxic ash. Their potential hazards to health have not been adequately assessed. To illustrate the policy issues surrounding waste incineration and resource recycling, we examine the case of U.S. Metals, a scrap metals recovery plant in Carteret, New Jersey. This plant emitted 20 kilograms of dioxin in its 25 years of operation. It also released 86 tons of lead annually; nearby air lead levels were repeatedly in violation of standards. Construction of a tall stack caused export of toxic emissions from the plant to Staten Island, New York; high concentrations of lead were documented in surface soil on Staten Island. Because neither the State of New Jersey nor the U.S. Environmental Protection Agency were willing to regulate emissions from the plant, New York, the downwind state, was forced to sue U.S. Metals in federal court. The suit resulted ultimately in closing the plant. The case illustrates the difficulties in regulating pollution across state lines, a difficulty compounded by the abdication of responsibility by state and federal agencies. Further, the episode appears paradigmatic of a disturbing trend by state and local governments to locate waste combustion facilities at sites which will resolve problems of solid waste by encouraging export of airborne pollutants across regulatory boundaries.

Methods for Environments and Contaminants: Hazardous Air Pollutants

EPA Pesticide Factsheets

EPA’s Office of Air Quality Planning and Standards estimated census tract annual average outdoor concentrations of 181i hazardous air pollutants, also known as air toxics, as part of EPA’s National Air Toxics Assessment (NATA) for the calendar year 2005.

CHANGES IN HEART RATE VARIABILITY AND LUNG FUNCTION OBSERVED IN NC PATROL TROOPERS EXPOSED TO PM AND AIR TOXICS

EPA Science Inventory

Changes in Heart Rate Variability and Lung Function in NC Patrol Troopers exposed to PM and Air Toxics

Michael Riediker1, Wayne E Cascio1, Robert B Devlin2, Thomas Griggs1&4, Margaret Herbst1, Ronald W Williams3, Steve P McCorquodale4, Philip A Bromberg1
1) University o...

A Quantitative Structure Activity Relationship for acute oral toxicity of pesticides on rats: Validation, domain of application and prediction.

PubMed

Hamadache, Mabrouk; Benkortbi, Othmane; Hanini, Salah; Amrane, Abdeltif; Khaouane, Latifa; Si Moussa, Cherif

2016-02-13

Quantitative Structure Activity Relationship (QSAR) models are expected to play an important role in the risk assessment of chemicals on humans and the environment. In this study, we developed a validated QSAR model to predict acute oral toxicity of 329 pesticides to rats because a few QSAR models have been devoted to predict the Lethal Dose 50 (LD50) of pesticides on rats. This QSAR model is based on 17 molecular descriptors, and is robust, externally predictive and characterized by a good applicability domain. The best results were obtained with a 17/9/1 Artificial Neural Network model trained with the Quasi Newton back propagation (BFGS) algorithm. The prediction accuracy for the external validation set was estimated by the Q(2)ext and the root mean square error (RMS) which are equal to 0.948 and 0.201, respectively. 98.6% of external validation set is correctly predicted and the present model proved to be superior to models previously published. Accordingly, the model developed in this study provides excellent predictions and can be used to predict the acute oral toxicity of pesticides, particularly for those that have not been tested as well as new pesticides. Copyright © 2015 Elsevier B.V. All rights reserved.

CHANGES IN LUNG FUNCTION OBSERVED IN A STUDY OF PM AND AIR TOXICS EXPOSURE TO NC HIGHWAY PATROL TROOPERS (COPP-STUDY)

EPA Science Inventory

Introduction: Car emissions have been identified as a major source of respirable particles. Individuals whose jobs involve being on the road, such as patrol troopers, may be exposed to high cencentrations of toxic air pollutants from vehicle emissions. This exposure might a...

Validation of zero-order feedback strategies for medium range air-to-air interception in a horizontal plane

NASA Technical Reports Server (NTRS)

Shinar, J.

1982-01-01

A zero order feedback solution of a variable speed interception game between two aircraft in the horizontal plane, obtained by using the method of forced singular perturbation (FSP), is compared with the exact open loop solution. The comparison indicates that for initial distances of separation larger than eight turning radii of the evader, the accuracy of the feedback approximation is better than one percent. The result validates the zero order FSP approximation for medium range air combat analysis.

Urban-air-toxics Monitoring Program, 1990

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-06-01

From March 1990 through February 1991 samples of ambient air were collected at 12 sites in the eastern part of the U.S. Every 12 days, air was integrated over 24-hour periods into passivated stainless steel canisters. Simultaneously, air was drawn through cartridges containing dinitrophenylhydrazine to collect carbonyl compounds. The samples were analyzed at a central laboratory for a total of 37 halogenated and aromatic hydrocarbons, formaldehyde, acetaldehyde, and other oxygenated species. The hydrocarbon species were analyzed by gas chromatography/multiple detectors and gas chromatography/mass spectrometry, while the carbonyl species were analyzed by liquid chromatography. Complete data for all the hydrocarbon samplesmore » are presented in the report.« less

REAL-TIME EMISSION CHARACTERIZATION OF ORGANIC AIR TOXIC POLLUTANTS DURING STEADY STATE AND TRANSIENT OPERATION OF A MEDIUM DUTY DIESEL ENGINE

EPA Science Inventory

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...

Occurrence and Concentrations of Toxic VOCs in the Ambient Air of Gumi, an Electronics-Industrial City in Korea

PubMed Central

Baek, Sung-Ok; Suvarapu, Lakshmi Narayana; Seo, Young-Kyo

2015-01-01

This study was carried out to characterize the occurrence and concentrations of a variety of volatile organic compounds (VOCs) including aliphatic, aromatic, halogenated, nitrogenous, and carbonyl compounds, in the ambient air of Gumi City, where a large number of electronics industries are found. Two field monitoring campaigns were conducted for a one year period in 2003/2004 and 2010/2011 at several sampling sites in the city, representing industrial, residential and commercial areas. More than 80 individual compounds were determined in this study, and important compounds were then identified according to their abundance, ubiquity and toxicity. The monitoring data revealed toluene, trichloroethylene and acetaldehyde to be the most significant air toxics in the city, and their major sources were mainly industrial activities. On the other hand, there was no clear evidence of an industrial impact on the concentrations of benzene and formaldehyde in the ambient air of the city. Overall, seasonal variations were not as distinct as locational variations in the VOCs concentrations, whereas the within-day variations showed a typical pattern of urban air pollution, i.e., increase in the morning, decrease in the afternoon, and an increase again in the evening. Considerable decreases in the concentrations of VOCs from 2003 to 2011 were observed. The reductions in the ambient concentrations were confirmed further by the Korean PRTR data in industrial emissions within the city. Significant decreases in the concentrations of benzene and acetaldehyde were also noted, whereas formaldehyde appeared to be almost constant between the both campaigns. The decreased trends in the ambient levels were attributed not only to the stricter regulations for VOCs in Korea, but also to the voluntary agreement of major companies to reduce the use of organic solvents. In addition, a site planning project for an eco-friendly industrial complex is believed to play a contributory role in improving

Urban Air Toxics Monitoring Program, 1989

DOE Office of Scientific and Technical Information (OSTI.GOV)

McAllister, R.A.; Moore, W.H.; Rice, J.

1990-10-01

From January 1989 through January 1990 samples of ambient air were collected at 14 sites in the eastern part of the U.S. Every 12 days, air was integrated over 24-hour periods into passivated stainless steel canisters. Simultaneously, air was drawn through cartridges containing dinitrophenylhydrazine to collect carbonyl compounds. The samples were analyzed at a central laboratory for a total of 37 halogenated and aromatic hydrocarbons, formaldehyde, acetaldehyde, and other oxygenated species. The hydrocarbon species were analyzed by gas chromatography/multiple detectors and gas chromatography/mass spectrometry, while the carbonyl species were analyzed by liquid chromatography. An extensive quality assurance program was carriedmore » on to secure high quality data. Complete data for all the carbonyl samples are presented in the report.« less

QUANTIFYING SUBGRID POLLUTANT VARIABILITY IN EULERIAN AIR QUALITY MODELS

EPA Science Inventory

In order to properly assess human risk due to exposure to hazardous air pollutants or air toxics, detailed information is needed on the location and magnitude of ambient air toxic concentrations. Regional scale Eulerian air quality models are typically limited to relatively coar...

Validation of a dew-point generator for pressures up to 6 MPa using nitrogen and air

NASA Astrophysics Data System (ADS)

Bosma, R.; Mutter, D.; Peruzzi, A.

2012-08-01

A new primary humidity standard was developed at VSL that, in addition to ordinary operation with air and nitrogen at atmospheric pressure, can be operated with other carrier gases such as natural gas at pressures up to 6 MPa and SF6 at pressures up to 1 MPa. The temperature range of the standard is from -80 °C to +20 °C. In this paper, we report the validation of the new primary dew-point generator in the temperature range -41 °C to +5 °C and the pressure range 0.1 MPa to 6 MPa using nitrogen and air. For the validation the flow through the dew-point generator was varied up to 10 l min-1 (at 23 °C and 1013 hPa) and the dew point of the gas entering the generator was varied up to 15 °C above the dew point exiting the generator. The validation results showed that the new generator, over the tested temperature and pressure range, can be used with a standard uncertainty of 0.02 °C frost/dew point. The measurements used for the validation at -41 °C and -20 °C with nitrogen and at +5 °C with air were also used to calculate the enhancement factor at pressures up to 6 MPa. For +5 °C the differences between the measured and literature values were compatible with the respective uncertainties. For -41 °C and -20 °C they were compatible only up to 3 MPa. At 6 MPa a discrepancy was observed.

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

PubMed

Lunder, Sonya; Woodruff, Tracey J; Axelrad, Daniel A

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 [NH3], copper [Cu], Cu compounds, nitric acid [HNO3], N-methyl-2-pyrrolidone, sulfuric acid [H2SO4], 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.

REAL TIME, ON-LINE CHARACTERIZATION OF DIESEL GENERATOR AIR TOXIC EMISSIONS BY RESONANCE ENHANCED MULTI-PHOTON IONIZATION TIME OF FLIGHT MASS SPECTROMETRY

EPA Science Inventory

The laser based resonance, enhanced multi-photon ionization time-of-flight mass spectrometry (REMPI-TOFMS) technique has been applied to the exhaust gas stream of a diesel generator to measure, in real time, concentration levels of aromatic air toxics. Volatile organic compounds ...

Modeling validation and control analysis for controlled temperature and humidity of air conditioning system.

PubMed

Lee, Jing-Nang; Lin, Tsung-Min; Chen, Chien-Chih

2014-01-01

This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14 °C, 0006 kg(w)/kg(da) in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system.

Modeling Validation and Control Analysis for Controlled Temperature and Humidity of Air Conditioning System

PubMed Central

Lee, Jing-Nang; Lin, Tsung-Min

2014-01-01

This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14°C, 0006 kgw/kgda in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system. PMID:25250390

Aerosolized ZnO nanoparticles induce toxicity in alveolar type II epithelial cells at the air-liquid interface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xie, Yumei; Williams, Nolann G.; Tolic, Ana

The majority of in vitro studies characterizing the impact of engineered nanoparticles (NPs) on cells that line the respiratory tract were conducted in cells exposed to NPs in suspension. This approach introduces processes that are unlikely to occur during inhaled NP exposures in vivo, such as the shedding of toxic doses of dissolved ions. ZnO NPs are used extensively and pose significant sources for human exposure. Exposures to airborne ZnO NPs can induce adverse effects, but the relevance of the dissolved Zn2+ to the observed effects in vivo is still unclear. Our goal was to mimic in vivo exposures tomore » airborne NPs and decipher the contribution of the intact NP from the contribution of the dissolved ions to airborne ZnO NP toxicity. We established the exposure of alveolar type II epithelial cells to aerosolized NPs at the air-liquid interface (ALI), and compared the impact of aerosolized ZnO NPs and NPs in suspension at the same cellular doses, measured as the number of particles per cell. By evaluating membrane integrity and cell viability 6 and 24 hours post exposure we found that aerosolized NPs induced toxicity at the ALI at doses that were in the same order of magnitude as doses required to induce toxicity in submersed cultures. In addition, distinct patterns of oxidative stress were observed in the two exposure systems. These observations unravel the ability of airborne ZnO NPs to induce toxicity without the contribution of dissolved Zn2+ and suggest distinct mechanisms at the ALI and in submersed cultures.« less

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

NASA Astrophysics Data System (ADS)

Nazaroff, William W.; Weschler, Charles J.

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 reacts rapidly with organics, leading to the formation of other potentially toxic air pollutants. Indoor reactive chemistry involving the nitrate radical and cleaning-product constituents is also of concern, since it produces organic nitrates as well as some of the same oxidation products generated by ozone and hydroxyl radicals. Few studies have directly addressed the indoor concentrations of TACs that might result from primary emissions or secondary pollutant formation following the use of cleaning agents and air fresheners. In this paper, we combine direct empirical evidence with the basic principles of indoor pollutant behavior and with information from relevant studies, to analyze and critically assess air pollutant exposures resulting from the use of cleaning products and air fresheners. Attention is focused on compounds that are listed as HAPs, TACs or Proposition 65 carcinogens/reproductive toxicants and compounds that can readily react to generate secondary pollutants. The toxicity of many of these secondary pollutants has yet to be evaluated. The inhalation

Method validation for methanol quantification present in working places

NASA Astrophysics Data System (ADS)

Muna, E. D. M.; Bizarri, C. H. B.; Maciel, J. R. M.; da Rocha, G. P.; de Araújo, I. O.

2015-01-01

Given the widespread use of methanol by different industry sectors and high toxicity associated with this substance, it is necessary to use an analytical method able to determine in a sensitive, precise and accurate levels of methanol in the air of working environments. Based on the methodology established by the National Institute for Occupational Safety and Health (NIOSH), it was validated a methodology for determination of methanol in silica gel tubes which had demonstrated its effectiveness based on the participation of the international collaborative program sponsored by the American Industrial Hygiene Association (AIHA).

US Commercial Air Tour Crashes, 2000–2011: Burden, Fatal Risk Factors, and FIA Score Validation

PubMed Central

Ballard, Sarah-Blythe; Beaty, Leland P.; Baker, Susan P.

2013-01-01

Introduction This study provides new public health data concerning the US commercial air tour industry. Risk factors for fatality in air tour crashes were analyzed to determine the value of the FIA score in predicting fatal outcomes. Methods Using the Federal Aviation Administration’s (FAA) General Aviation and Air Taxi Survey and National Transportation Safety Board data, the incidence of commercial air tour crashes from 2000 through 2010 was calculated. Fatality risk factors for crashes occurring from 2000 through 2011 were analyzed using regression methods. The FIA score, Li and Baker’s fatality risk index, was validated using receiver operating characteristic (ROC) curves. Results The industry-wide commercial air tour crash rate was 2.7 per 100,000 flight hours. The incidence rates of Part 91 and 135 commercial air tour crashes were 3.4 and 2.3 per 100,000 flight hours, respectively (relative risk [RR] 1.5, 95% confidence interval [CI] 1.1–2.1, P=0.015). Of the 152 air tour crashes that occurred from 2000 through 2011, 30 (20%) involved at least one fatality and, on average, 3.5 people died per fatal crash. Fatalities were associated with three major risk factors: fire (Adjusted odds ratio [AOR] 5.1, 95% CI 1.5–16.7, P=0.008), instrument meteorological conditions (AOR 5.4, 95% CI 1.1–26.4, P=0.038), and off-airport location (AOR 7.2, 95% CI 1.6–33.2, P=0.011). The area under the FIA Score’s ROC curve was 0.79 (95% CI 0.71–0.88). Discussion Commercial air tour crash rates were high relative to similar commercial aviation operations. Disparities between Part 91 and 135 air tour crash rates reflect regulatory disparities that require FAA action. The FIA Score appeared to be a valid measurement of fatal risk in air tour crashes. The FIA should prioritize interventions that address the three major risk factors identified by this study. PMID:23631935

Characterization and Quantification of Hexavalent Chromium and Other Toxic Metals in the Air of Communities Surrounding Metal Processing Facilities

NASA Astrophysics Data System (ADS)

Pikelnaya, O.; Polidori, A.; Low, J.

2017-12-01

Hexavalent chromium [Cr(VI)] and other toxic metals are often emitted during metal forging, cutting, grinding and plating operations. In the South Coast Air Basin (SCAB) many of such operations are conducted by relatively small facilities intertwined within residential communities in the cities of Paramount, Compton, Long Beach and Anaheim. In response to the city of Paramount community members' complaints of "metallic" odors, the South Coast Air Quality Management District (SCAQMD) initiated a local air sampling study for toxic metals, which found elevated Cr(VI) and nickel levels in the community downwind of selected metal processing facilities. SCAQMD worked with these facilities to reduce the emissions from their metal grinding operations, which resulted in substantial reduced nickel levels, but did not reduce Cr(VI) levels. In order to fully understand the source(s) of these emissions, SCAQMD has been deploying portable samplers for Cr(VI) monitoring throughout the city of Paramount since October 2016. During this presentation we will discuss the results of more than a year of Cr(VI) analyses of samplers collected throughout the City of Paramount, as well as data from a continuous metal monitor deployed at one of the sites. We will also discuss options and challenges for expanding of Cr(VI) monitoring to other communities in the SCAB that are adjacent to metal forging and grinding operations; and explore emerging new technologies to address such monitoring challenges.

The importance of toxicity in determining the impact of hazardous air pollutants on the respiratory health of children in Tennessee.

PubMed

Moore, Roberta J H; Hotchkiss, Julie L

2016-09-01

Respiratory diseases, exacerbated through point source pollution, are currently among the leading causes of hospitalization of children in the United States. This paper investigates the relationship between the proximity of hazardous air pollutants (HAPs) emitted from Toxic Release Inventory (TRI) facilities and the number of children diagnosed in hospitals with a respiratory disease in Tennessee. The importance of controlling for toxicity of those HAPs is of particular interest. Hospital discharge, socioeconomic, TRI emission, and HAP toxicity data are used to estimate, via Generalized Linear Methods, a logistic regression model describing the relationship between the percent of children living in a zip code area treated for respiratory illness and the average annual emissions over the previous 10 years of HAPs from TRI sites in that area. Controlling for area socioeconomic characteristics, we find that accounting for toxicity is important in uncovering the relationship between HAP emissions and respiratory health of children. A one standard deviation increase in toxicity-weighted emissions per 100 square miles is associated with an increase in the number of children diagnosed with asthma (chronic bronchitis) by about 1205 (260). The evidence suggests that, with a goal to improving children's respiratory health, monitoring the toxicity of chemicals being emitted is at least as important as simply monitoring total emission levels. This suggests that the EPA should consider making efforts toward establishing toxicity adjusted emission guidelines. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development, validation, and fairness of a biographical data questionnaire for the air traffic control specialist occupation.

DOT National Transportation Integrated Search

2012-12-01

Development and validation of a biographical data (biodata) instrument for selection into the Air Traffic : Control Specialist occupation is described. Bootstrapping was used to estimate correlations between item : responses to the Applicant Ba...

Validation of photosynthetic-fluorescence parameters as biomarkers for isoproturon toxic effect on alga Scenedesmus obliquus.

PubMed

Dewez, David; Didur, Olivier; Vincent-Héroux, Jonathan; Popovic, Radovan

2008-01-01

Photosynthetic-fluorescence parameters were investigated to be used as valid biomarkers of toxicity when alga Scenedesmus obliquus was exposed to isoproturon [3-(4-isopropylphenyl)-1,1-dimethylurea] effect. Chlorophyll fluorescence induction of algal cells treated with isoproturon showed inactivation of photosystem II (PSII) reaction centers and strong inhibition of PSII electron transport. A linear correlation was found (R2>or=0.861) between the change of cells density affected by isoproturon and the change of effective PSII quantum yield (PhiM'), photochemical quenching (qP) and relative photochemical quenching (qP(rel)) values. The cells density was also linearly dependent (R2=0.838) on the relative unquenched fluorescence parameter (UQF(rel)). Non-linear correlation was found (R2=0.937) only between cells density and the energy transfer efficiency from absorbed light to PSII reaction center (ABS/RC). The order of sensitivity determined by the EC-50% was: UQF(rel)>PhiM'>qP>qP(rel)>ABS/RC. Correlations between cells density and those photosynthetic-fluorescence parameters provide supporting evidence to use them as biomarkers of toxicity for environmental pollutants.

[Reliability and validity of the Chinese version on Comprehensive Scores for Financial Toxicity based on the patient-reported outcome measures].

PubMed

Yu, H H; Bi, X; Liu, Y Y

2017-08-10

Objective: To evaluate the reliability and validity of the Chinese version on comprehensive scores for financial toxicity (COST), based on the patient-reported outcome measures. Methods: A total of 118 cancer patients were face-to-face interviewed by well-trained investigators. Cronbach's α and Pearson correlation coefficient were used to evaluate reliability. Content validity index (CVI) and exploratory factor analysis (EFA) were used to evaluate the content validity and construct validity, respectively. Results: The Cronbach's α coefficient appeared as 0.889 for the whole questionnaire, with the results of test-retest were between 0.77 and 0.98. Scale-content validity index (S-CVI) appeared as 0.82, with item-content validity index (I-CVI) between 0.83 and 1.00. Two components were extracted from the Exploratory factor analysis, with cumulative rate as 68.04% and loading>0.60 on every item. Conclusion: The Chinese version of COST scale showed high reliability and good validity, thus can be applied to assess the financial situation in cancer patients.

CASTNet Air Toxics Monitoring Program (CATMP): VOC and carbonyl data for July, 1993 through March, 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harlos, D.P.; Edgerton, E.S.

1994-12-31

The US EPA has, under the auspices of the CASTNet program (Clean Air Status and Trends Network), initiated the CASTNet Air Toxics Monitoring Program (CATMP). Volatile Organic Compounds (VOC) and carbonyls and metals are sampled for 24-hour periods on a 12-day schedule using TO-14 samplers (SUMMA canisters) and dinitrophenylhydrazine-coated (dmph) sorbent cartridges and high volume particle samplers. Sampling was begun at most sites in July of 1993. The sites are operated by state and local air pollution control programs and all analysis is performed by Environmental Science and Engineering (ESE) in Gainesville, Florida. The network currently supports 15 VOC sites,more » of which 7 also sample carbonyls. Three sites sample metals only in Pinellas County, Florida. The limits of detection of 0.05 ppb for VOCs allow routine tracking of a wide range of pollutants including several greenhouse gases, transportation pollutants and photochemically-derived compounds. The sites range from major urban areas (Chicago, St. Louis) to a rural village (Waterbury, Vermont). Results of the first three quarters of VOC and carbonyl data collection are summarized in this presentation.« less

Validation of a biotic ligand model on site-specific copper toxicity to Daphnia magna in the Yeongsan River, Korea.

PubMed

Park, Jinhee; Ra, Jin-Sung; Rho, Hojung; Cho, Jaeweon; Kim, Sang Don

2018-03-01

The objective of this study was to determine whether the water effect ratio (WER) or biotic ligand model (BLM) could be applied to efficiently develop water quality criteria (WQC) in Korea. Samples were collected from 12 specific sites along the Yeongsan River (YSR), Korea, including two sewage treatment plants and one estuary lake. A copper toxicity test using Daphnia magna was performed to determine the WER and to compare to the BLM prediction. The results of the WER from YSR samples also indicated significantly different copper toxicities in all sites. The model-based predictions showed that effluent and estuary waters had significantly different properties in regard to their ability to be used to investigate water characteristics and copper toxicity. It was supposed that the slight water characteristics changes, such as pH, DOC, hardness, conductivity, among others, influence copper toxicity, and these variable effects on copper toxicity interacted with the water composition. The 38% prediction was outside of the validation range by a factor of two in all sites, showing a poor predictive ability, especially in STPs and streams adjacent to the estuary, while the measured toxicity was more stable. The samples that ranged from pH 7.3-7.7 generated stable predictions, while other samples, including those with lower and the higher pH values, led to more unstable predictions. The results also showed that the toxicity of Cu in sample waters to D. magna was closely proportional to the amounts of acidity, including the carboxylic and phenolic groups, as well as the DOC concentrations. Consequently, the acceptable prediction of metal toxicity in various water samples needs the site-specific results considering the water characteristics such as pH and DOC properties particularly in STPs and estuary regions. Copyright © 2017 Elsevier Inc. All rights reserved.

Egg incubation position affects toxicity of air cell administered PCB 126 (3,3?4,4?,5- pentachlorobiphenyl) in chicken (Gallus domesticus) embryos

USGS Publications Warehouse

McKernan, M.A.; Rattner, B.A.; Hale, R.C.; Ottinger, M.A.

2007-01-01

The avian egg is used extensively for chemical screening and determining the relative sensitivity of species to environmental contaminants (e.g., metals, pesticides, polyhalogenated compounds). The effect of egg incubation position on embryonic survival, pipping, and hatching success was examined following air cell administration of polychlorinated biphenyl (PCB) congener 126 (3,3',4,4',5-pentachlorobiphenyl [PCB 126]; 500?2,000 pg/g egg) on day 4 of development in fertile chicken (Gallus gallus) eggs. Depending on dose, toxicity was found to be up to nine times greater in vertically versus horizontally incubated eggs. This may be due to enhanced embryonic exposure to the injection bolus in vertically incubated eggs compared to more gradual uptake in horizontally incubated eggs. Following air cell administration of PCB 126, horizontal incubation of eggs may more closely approximate uptake and toxicity that has been observed with naturally incorporated contaminants. These data have implications for chemical screening and use of laboratory data for ecological risk assessments.

Toxicity studies of a polyurethane rigid foam

NASA Technical Reports Server (NTRS)

Hilado, C. J.; Schneider, J. E.

1977-01-01

Relative toxicity tests were performed on a polyurethane foam containing a trimethylopropane-based polyol and an organophosphate flame retardant. The routine screening procedure involved the exposure of four Swiss albino male mice in a 4.2 liter hemispherical chamber to the products generated by pyrolyzing a 1.00 g sample at a heating rate of 40 deg C/min from 200 to 800 C in the absence of air flow. In addition to the routine screening, experiments were performed with a very rapid rise to 800 C, with nominal 16 and 48 ml/sec air flow and with varying sample rates. No unusual toxicity was observed with either gradual or rapid pyrolysis to 800 C. Convulsions and seizures similar to those previously reported were observed when the materials were essentially flash pyrolyzed at 800 C in the presence of air flow, and the toxicity appeared unusual because of low sample weights required to produce death.

Feasibility of a Networked Air Traffic Infrastructure Validation Environment for Advanced NextGen Concepts

NASA Technical Reports Server (NTRS)

McCormack, Michael J.; Gibson, Alec K.; Dennis, Noah E.; Underwood, Matthew C.; Miller,Lana B.; Ballin, Mark G.

2013-01-01

Abstract-Next Generation Air Transportation System (NextGen) applications reliant upon aircraft data links such as Automatic Dependent Surveillance-Broadcast (ADS-B) offer a sweeping modernization of the National Airspace System (NAS), but the aviation stakeholder community has not yet established a positive business case for equipage and message content standards remain in flux. It is necessary to transition promising Air Traffic Management (ATM) Concepts of Operations (ConOps) from simulation environments to full-scale flight tests in order to validate user benefits and solidify message standards. However, flight tests are prohibitively expensive and message standards for Commercial-off-the-Shelf (COTS) systems cannot support many advanced ConOps. It is therefore proposed to simulate future aircraft surveillance and communications equipage and employ an existing commercial data link to exchange data during dedicated flight tests. This capability, referred to as the Networked Air Traffic Infrastructure Validation Environment (NATIVE), would emulate aircraft data links such as ADS-B using in-flight Internet and easily-installed test equipment. By utilizing low-cost equipment that is easy to install and certify for testing, advanced ATM ConOps can be validated, message content standards can be solidified, and new standards can be established through full-scale flight trials without necessary or expensive equipage or extensive flight test preparation. This paper presents results of a feasibility study of the NATIVE concept. To determine requirements, six NATIVE design configurations were developed for two NASA ConOps that rely on ADS-B. The performance characteristics of three existing in-flight Internet services were investigated to determine whether performance is adequate to support the concept. Next, a study of requisite hardware and software was conducted to examine whether and how the NATIVE concept might be realized. Finally, to determine a business case

[Air pollution and cardiovascular toxicity: known risks].

PubMed

Kostrzewa, A; Filleul, L; Eilstein, D; Harrabi, I; Tessier, J F

2004-03-01

Review of studies about epidemiological and physiopathological knowledge of ambient air particles short-term cardio-vascular effects. CURRENTS AND STRONG POINTS: Many studies, in contrasted countries for pollution's sources, meteorological conditions or socio-demographical characteristics, have shown health effects due to ambient air particles. After having studied mainly the respiratory effects of particulate air pollution, epidemiologists are now interested in the cardio-vascular effects of ambient air particles. In fact, serious effects seem to exist in fragile people which can get to emergency department visits, hospitalisation and even death. In addition, studies have shown less serious effects, but likely to be frequent (cardiac symptoms, and stoppages for cardio-vascular causes, notably). The exact mechanism by which particles have cardio-vascular adverse health effects is unknown, but experimental and epidemiological studies have led to several hypotheses: local pulmonary effects seem to be followed by systemic effects, which would be responsible for effects on the electrical activity of the heart through cardiac autonomic dysfunction and effects on the blood supply to the heart. The objective of this work is to summarise epidemiological and physiopathological knowledge about the cardio-vascular effects of ambient air particles. To evaluate the real importance of cardio-vascular effects due to particulate air pollution and to identify their exact mechanism, a more precise knowledge of detailed causes of deaths and hospitalisations and a better knowledge of less serious effects, but likely to be frequent, is necessary. Equally, a detailed identification of fragile people is essential for developing preventive actions.

The selection of air traffic control specialists : two studies demonstrating methods to insure an accurate validity coefficient for selection devices.

DOT National Transportation Integrated Search

1979-03-01

There are several conditions that can influence the calculation of the statistical validity of a test battery such as that used to selected Air Traffic Control Specialists. Two conditions of prime importance to statistical validity are recruitment pr...

Validating novel air pollution sensors to improve exposure estimates for epidemiological analyses and citizen science.

PubMed

Jerrett, Michael; Donaire-Gonzalez, David; Popoola, Olalekan; Jones, Roderic; Cohen, Ronald C; Almanza, Estela; de Nazelle, Audrey; Mead, Iq; Carrasco-Turigas, Glòria; Cole-Hunter, Tom; Triguero-Mas, Margarita; Seto, Edmund; Nieuwenhuijsen, Mark

2017-10-01

Low cost, personal air pollution sensors may reduce exposure measurement errors in epidemiological investigations and contribute to citizen science initiatives. Here we assess the validity of a low cost personal air pollution sensor. Study participants were drawn from two ongoing epidemiological projects in Barcelona, Spain. Participants repeatedly wore the pollution sensor - which measured carbon monoxide (CO), nitric oxide (NO), and nitrogen dioxide (NO 2 ). We also compared personal sensor measurements to those from more expensive instruments. Our personal sensors had moderate to high correlations with government monitors with averaging times of 1-h and 30-min epochs (r ~ 0.38-0.8) for NO and CO, but had low to moderate correlations with NO 2 (~0.04-0.67). Correlations between the personal sensors and more expensive research instruments were higher than with the government monitors. The sensors were able to detect high and low air pollution levels in agreement with expectations (e.g., high levels on or near busy roadways and lower levels in background residential areas and parks). Our findings suggest that the low cost, personal sensors have potential to reduce exposure measurement error in epidemiological studies and provide valid data for citizen science studies. Copyright © 2017 Elsevier Inc. All rights reserved.

Validation of a Dumbbell Body Sway Test in Olympic Air Pistol Shooting

PubMed Central

Mon, Daniel; Zakynthinaki, Maria S.; Cordente, Carlos A.; Monroy Antón, Antonio; López Jiménez, David

2014-01-01

We present and validate a test able to provide reliable body sway measurements in air pistol shooting, without the use of a gun. 46 senior male pistol shooters who participated in Spanish air pistol championships participated in the study. Body sway data of two static bipodal balance tests have been compared: during the first test, shooting was simulated by use of a dumbbell, while during the second test the shooters own pistol was used. Both tests were performed the day previous to the competition, during the official training time and at the training stands to simulate competition conditions. The participantś performance was determined as the total score of 60 shots at competition. Apart from the commonly used variables that refer to movements of the shooters centre of pressure (COP), such as COP displacements on the X and Y axes, maximum and average COP velocities and total COP area, the present analysis also included variables that provide information regarding the axes of the COP ellipse (length and angle in respect to X). A strong statistically significant correlation between the two tests was found (with an interclass correlation varying between 0.59 and 0.92). A statistically significant inverse linear correlation was also found between performance and COP movements. The study concludes that dumbbell tests are perfectly valid for measuring body sway by simulating pistol shooting. PMID:24756067

Cellular Sentinels Toxicity Platform

DTIC Science & Technology

2017-02-01

Air Force Research Laboratory 711th Human Performance Wing U.S. Air Force School of Aerospace Medicine Aeromedical Research Department 2510 Fifth St...toxicity testing is to assess the likely risks posed to human populations at ambient exposure levels. Unfortunately, current approaches to toxicology... human populations at ambient exposure levels. For the past 50 years, this goal has been met by high dose testing in experimental animals with

40 CFR Table 3 to Subpart X of... - Toxic Equivalency Factors

Code of Federal Regulations, 2012 CFR

2012-07-01

... Subpart X of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Standards For Hazardous Air Pollutants From Secondary Lead Smelting Pt. 63, Subpt. X, Table 3 Table 3 to Subpart X of Part 63—Toxic Equivalency Factors Dioxin/furan congener Toxic equivalency factor 2,3,7,8...

40 CFR Table 3 to Subpart X of... - Toxic Equivalency Factors

Code of Federal Regulations, 2013 CFR

2013-07-01

... Subpart X of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Standards For Hazardous Air Pollutants From Secondary Lead Smelting Pt. 63, Subpt. X, Table 3 Table 3 to Subpart X of Part 63—Toxic Equivalency Factors Dioxin/furan congener Toxic equivalency factor 2,3,7,8...

California wildfires of 2008: coarse and fine particulate matter toxicity.

PubMed

Wegesser, Teresa C; Pinkerton, Kent E; Last, Jerold A

2009-06-01

During the last week of June 2008, central and northern California experienced thousands of forest and brush fires, giving rise to a week of severe fire-related particulate air pollution throughout the region. California experienced PM(10-2.5) (particulate matter with mass median aerodynamic diameter > 2.5 mum to < 10 mum; coarse ) and PM(2.5) (particulate matter with mass median aerodynamic diameter < 2.5 mum; fine) concentrations greatly in excess of the air quality standards and among the highest values reported at these stations since data have been collected. These observations prompt a number of questions about the health impact of exposure to elevated levels of PM(10-2.5) and PM(2.5) and about the specific toxicity of PM arising from wildfires in this region. Toxicity of PM(10-2.5) and PM(2.5) obtained during the time of peak concentrations of smoke in the air was determined with a mouse bioassay and compared with PM samples collected under normal conditions from the region during the month of June 2007. Concentrations of PM were not only higher during the wildfire episodes, but the PM was much more toxic to the lung on an equal weight basis than was PM collected from normal ambient air in the region. Toxicity was manifested as increased neutrophils and protein in lung lavage and by histologic indicators of increased cell influx and edema in the lung. We conclude that the wildfire PM contains chemical components toxic to the lung, especially to alveolar macrophages, and they are more toxic to the lung than equal doses of PM collected from ambient air from the same region during a comparable season.

Catalytic Destruction Of Toxic Organic Compounds

NASA Technical Reports Server (NTRS)

Voecks, Gerald E.

1990-01-01

Proposed process disposes of toxic organic compounds in contaminated soil or carbon beds safely and efficiently. Oxidizes toxic materials without producing such other contaminants as nitrogen oxides. Using air, fuel, catalysts, and steam, system consumes less fuel and energy than decontamination processes currently in use. Similar process regenerates carbon beds used in water-treatment plants.

75 FR 29699 - Approval and Promulgation of Air Quality Implementation Plans: Florida; Approval of Section 110(a...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-27

... Section, Air Planning Branch, Air, Pesticides and Toxics Management Division, U.S. Environmental...: Lynorae Benjamin, Chief, Regulatory Development Section, Air Planning Branch, Air, Pesticides and Toxics... Bradley, Regulatory Development Section, Air Planning Branch, Air, Pesticides and Toxics Management...

77 FR 35652 - Approval and Promulgation of Implementation Plans and Designations of Areas for Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-14

... Planning Branch, Air, Pesticides and Toxics Management Division, U.S. Environmental Protection Agency..., Regulatory Development Section, Air Planning Branch, Air, Pesticides and Toxics Management Division, U.S... Development Section, Air Planning Branch, Air, Pesticides and Toxics Management Division, U.S. Environmental...

On the validity of the incremental approach to estimate the impact of cities on air quality

NASA Astrophysics Data System (ADS)

Thunis, Philippe

2018-01-01

The question of how much cities are the sources of their own air pollution is not only theoretical as it is critical to the design of effective strategies for urban air quality planning. In this work, we assess the validity of the commonly used incremental approach to estimate the likely impact of cities on their air pollution. With the incremental approach, the city impact (i.e. the concentration change generated by the city emissions) is estimated as the concentration difference between a rural background and an urban background location, also known as the urban increment. We show that the city impact is in reality made up of the urban increment and two additional components and consequently two assumptions need to be fulfilled for the urban increment to be representative of the urban impact. The first assumption is that the rural background location is not influenced by emissions from within the city whereas the second requires that background concentration levels, obtained with zero city emissions, are equal at both locations. Because the urban impact is not measurable, the SHERPA modelling approach, based on a full air quality modelling system, is used in this work to assess the validity of these assumptions for some European cities. Results indicate that for PM2.5, these two assumptions are far from being fulfilled for many large or medium city sizes. For this type of cities, urban increments are largely underestimating city impacts. Although results are in better agreement for NO2, similar issues are met. In many situations the incremental approach is therefore not an adequate estimate of the urban impact on air pollution. This poses issues in terms of interpretation when these increments are used to define strategic options in terms of air quality planning. We finally illustrate the interest of comparing modelled and measured increments to improve our confidence in the model results.

A 13-year retrospective study evaluating the efficacy of using air-fluidised beds for toxic epidermal necrolysis patients.

PubMed

Xia, Weidong; Mao, Cong; Luo, Xu; Xu, Jianjun; Chen, Xiaofeng; Lin, Cai

2016-08-01

Toxic epidermal necrolysis (TEN) is a potentially life-threatening dermatological disease involving large areas of skin loss with systemic symptoms. This study evaluated the efficacy of air-fluidised bed therapy for TEN patients. Of 27 people with TEN, 11 used air-fluidised beds (the air-fluidised group) and 16 used standard beds (the control group). Days to complete re-epithelialisation, re-epithelialisation rate, incidence of complications, mortality, pain measured by visual analogue score and the incidence of cutaneous infection were compared in these groups. The mean body surface area of involvement was 77.0 ± 11.8% and baseline mean severity-of-illness score for TEN (SCORTEN) was 2.81 ± 1.08. The re-epithelialisation rate in the air-fluidised group was 100% but was only 56.3% in the control group (P < 0.05). There was a significant difference in the time taken to complete re-epithelialisation between the air-fluidised group (13 days [95% CI: 9.0-17.0]) and the control group (21 days [16.5-25.5], P < 0.05). Furthermore, the incidence of complications was 18% in the air-fluidised group versus 75% in the control group, including fewer cutaneous infections (P < 0.05). There was a significant reduction in pain among the air-fluidised group compared with the control group (P < 0.05). There were no deaths in the air-fluidised group while 19% of the control group died. Air-fluidised beds can reduce the time to complete re-epithelialisation, relieve pain and increase the re-epithelialisation rate of TEN patients, but there was no significant difference between them in mortality rate in our study. © 2015 The Australasian College of Dermatologists.

Effect of protective filters on fire fighter respiratory health: field validation during prescribed burns.

PubMed

De Vos, Annemarie J B M; Cook, Angus; Devine, Brian; Thompson, Philip J; Weinstein, Philip

2009-01-01

Bushfire smoke contains a range of air toxics. To prevent inhalation of these toxics, fire fighters use respiratory equipment. Yet, little is known about the effectiveness of the equipment on the fire ground. Experimental trials in a smoke chamber demonstrated that, the particulate/organic vapor/formaldehyde (POVF) filter performed best under simulated conditions. This article reports on the field validation trials during prescribed burns in Western Australia. Sixty-seven career fire fighters from the Fire and Emergency Services Authority of Western Australia were allocated one of the three types of filters. Spirometry, oximetry, self-reported symptom, and personal air sampling data were collected before, during and after exposure to bushfire smoke from prescribed burns. Declines in FEV(1) and SaO(2) were demonstrated after 60 and 120 min exposure. A significant higher number of participants in the P filter group reported increases in respiratory symptoms after the exposure. Air sampling inside the respirators demonstrated formaldehyde levels significantly higher in the P filter group compared to the POV and the POVF filter group. The field validation trials during prescribed burns supported the findings from the controlled exposure trials in the smoke chamber. Testing the effectiveness of three types of different filters under bushfire smoke conditions in the field for up to 2 hr demonstrated that the P filter is ineffective in filtering out respiratory irritants. The performance of the POV and the POVF filter appears to be equally effective after 2 hr bushfire smoke exposure in the field.

[Validation of measurement methods and estimation of uncertainty of measurement of chemical agents in the air at workstations].

PubMed

Dobecki, Marek

2012-01-01

This paper reviews the requirements for measurement methods of chemical agents in the air at workstations. European standards, which have a status of Polish standards, comprise some requirements and information on sampling strategy, measuring techniques, type of samplers, sampling pumps and methods of occupational exposure evaluation at a given technological process. Measurement methods, including air sampling and analytical procedure in a laboratory, should be appropriately validated before intended use. In the validation process, selected methods are tested and budget of uncertainty is set up. The validation procedure that should be implemented in the laboratory together with suitable statistical tools and major components of uncertainity to be taken into consideration, were presented in this paper. Methods of quality control, including sampling and laboratory analyses were discussed. Relative expanded uncertainty for each measurement expressed as a percentage, should not exceed the limit of values set depending on the type of occupational exposure (short-term or long-term) and the magnitude of exposure to chemical agents in the work environment.

Usefulness of AIRS-Derived OLR, Temperature, Water Vapor and Cloudiness Anomaly Trends for GCM Validation

NASA Technical Reports Server (NTRS)

Molnar, Gyula I.; Susskind, Joel; Iredell, Lena F.

2010-01-01

Mainly due to their global nature, satellite observations can provide a very useful basis for GCM validations. In particular, satellite sounders such as AIRS provide 3-D spatial information (most useful for GCMs), so the question arises: can we use AIRS datasets for climate variability assessments? We show that the recent (September 2002 February 2010) CERES-observed negative trend in OLR of approx.-0.1 W/sq m/yr averaged over the globe is found in the AIRS OLR data as well. Most importantly, even minute details (down to 1 x 1 degree GCM-scale resolution) of spatial and temporal anomalies and trends of OLR as observed by CERES and computed based on AIRS-retrieved surface and atmospheric geophysical parameters over this time period are essentially the same. The correspondence can be seen even in the very large spatial variations of these trends with local values ranging from -2.6 W/sq m/yr to +3.0 W/sq m/yr in the tropics, for example. This essentially perfect agreement of OLR anomalies and trends derived from observations by two different instruments, in totally independent and different manners, implies that both sets of results must be highly accurate, and indirectly validates the anomalies and trends of other AIRS derived products as well. These products show that global and regional anomalies and trends of OLR, water vapor and cloud cover over the last 7+ years are strongly influenced by EI-Nino-La Nina cycles . We have created climate parameter anomaly datasets using AIRS retrievals which can be compared directly with coupled GCM climate variability assessments. Moreover, interrelationships of these anomalies and trends should also be similar between the observed and GCM-generated datasets, and, in cases of discrepancies, GCM parameterizations could be improved based on the relationships observed in the data. First, we assess spatial "trends" of variability of climatic parameter anomalies [since anomalies relative to the seasonal cycle are good proxies of

75 FR 51968 - Outer Continental Shelf Air Regulations Consistency Update for Massachusetts

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-24

... comments to: Ida McDonnell, Air Permits, Toxics and Indoor Air Unit, Office of Ecosystem Protection, U.S... INFORMATION CONTACT: Ida E. McDonnell, Air Permits, Toxics and Indoor Air Unit, U.S. Environmental Protection... Continental Shelf Air Regulations Consistency Update for Massachusetts AGENCY: Environmental Protection Agency...

Community Multiscale Air Quality Modeling System (CMAQ)

EPA Pesticide Factsheets

CMAQ is a computational tool used for air quality management. It models air pollutants including ozone, particulate matter and other air toxics to help determine optimum air quality management scenarios.

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

PubMed

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.

Controlling Indoor Air Pollution.

ERIC Educational Resources Information Center

Nero, Anthony V, Jr.

1988-01-01

Discusses the health risks posed by indoor air pollutants, such as airborne combustion products, toxic chemicals, and radioactivity. Questions as to how indoor air might be regulated. Calls for new approaches to environmental protection. (TW)

Future research needs associated with the assessment of potential human health risks from exposure to toxic ambient air pollutants.

PubMed Central

Möller, L; Schuetzle, D; Autrup, H

1994-01-01

This paper presents key conclusions and future research needs from a Workshop on the Risk Assessment of Urban Air, Emissions, Exposure, Risk Identification, and Quantification, which was held in Stockholm during June 1992 by 41 participants from 13 countries. Research is recommended in the areas of identification and quantification of toxics in source emissions and ambient air, atmospheric transport and chemistry, exposure level assessment, the development of improved in vitro bioassays, biomarker development, the development of more accurate epidemiological methodologies, and risk quantification techniques. Studies are described that will be necessary to assess and reduce the level of uncertainties associated with each step of the risk assessment process. International collaborative research efforts between industry and government organizations are recommended as the most effective way to carry out this research. PMID:7529703

1990 Clean Air Act Amendment Summary

EPA Pesticide Factsheets

In 1989, President George W. Bush proposed revisions to the Clean Air Act designed to curb acid rain, urban air pollution, and toxic air emissions. The proposal also called for establishing a national permits program.

Impact of secondary generated minerals on toxic element immobilization for air pollution control fly ash of a municipal solid waste incinerator.

PubMed

Kitamura, Hiroki; Dahlan, Astryd Viandila; Tian, Yu; Shimaoka, Takayuki; Yamamoto, Takashi; Takahashi, Fumitake

2018-05-12

Impacts of secondary generated minerals on mineralogical and physical immobilization of toxic elements were investigated for chelate-treated air pollution control (APC) fly ash of a municipal solid waste incinerator. Scanning electron microscope (SEM) observation showed that ettringite was generated after the moistening treatment with/without chelate. Although ettringite can incorporate toxic elements into its structure, elemental analysis by energy dispersive X-ray could not find concentrated points of toxic elements in ettringite structure. This implies that mineralogical immobilization of toxic element by the encapsulation to ettringite structure seems to be limited. Physical immobilization was also investigated by SEM observation of the same APC fly ash particles before and after the moistening treatment. The transfer of soluble elements was inhibited only when insoluble minerals such as gypsum were generated and covered the surface of fly ash particles. Neoformed insoluble minerals prevented soluble elements from leaching and transfer. However, such physical immobilization seems to be limited because insoluble mineral formation with surface coverage was monitored only one time of more than 20 observations. Although uncertainty owing to limited samples with limited observations should be considered, this study concludes that mineralogical and physical immobilization of toxic elements by secondary minerals is limited although secondary minerals are always generated on the surface of APC fly ash particles during chelate treatment.

High Time Resolution Measurements of VOCs from Vehicle Cold Starts: The Air Toxic Cold Start Pulse

NASA Astrophysics Data System (ADS)

Jobson, B. T.; Huangfu, Y.; Vanderschelden, G. S.

2017-12-01

Pollutants emitted during motor vehicle cold starts, especially in winter in some climates, is a significant source of winter time air pollution. While data exist for CO, NO, and total hydrocarbon emissions from federal testing procedures for vehicle emission certification, little is known about the emission rates of individual volatile organic compounds, in particular the air toxics benzene, formaldehyde, and acetaldehyde. Little is known about the VOC speciation and temperature dependence for cold starts. The US EPA vehicle emission model MOVES assumes that cold start emissions have the same speciation profile as running emissions. We examined this assumption by measuring cold start exhaust composition for 4 vehicles fueled with E10 gasoline over a temperature range of -4°C to 10°C in winter of 2015. The extra cold start emissions were determined by comparison with emissions during engine idling. In addition to CO and NOx measurements a proton transfer reaction mass spectrometer was used to measure formaldehyde, acetaldehyde, benzene, toluene, and C2-alkylbenzenes at high time resolution to compare with the cold start emission speciation profiles used in the EPA MOVES2014 model. The results show that after the vehicle was started, CO mixing ratios can reach a few percent of the exhaust and then drop to several ppmv within 2 minutes of idling, while NOx showed different temporal behaviors among the four vehicles. VOCs displayed elevated levels during cold start and the peak mixing ratios can be two orders higher than idling phase levels. Molar emission ratios relative to toluene were used to compare with the emission ratio used in MOVES2014 and we found the formaldehyde-to-toluene emission ratio was about 0.19, which is 5 times higher than the emission ratio used in MOVES2014 and the acetaldehyde-to-toluene emission ratios were 0.86-0.89, which is 8 times higher than the ones in MOVES2014. The C2-alkylbenzene-to-toluene ratio agreed well with moves. Our results

Validation of selected analytical methods using accuracy profiles to assess the impact of a Tobacco Heating System on indoor air quality.

PubMed

Mottier, Nicolas; Tharin, Manuel; Cluse, Camille; Crudo, Jean-René; Lueso, María Gómez; Goujon-Ginglinger, Catherine G; Jaquier, Anne; Mitova, Maya I; Rouget, Emmanuel G R; Schaller, Mathieu; Solioz, Jennifer

2016-09-01

Studies in environmentally controlled rooms have been used over the years to assess the impact of environmental tobacco smoke on indoor air quality. As new tobacco products are developed, it is important to determine their impact on air quality when used indoors. Before such an assessment can take place it is essential that the analytical methods used to assess indoor air quality are validated and shown to be fit for their intended purpose. Consequently, for this assessment, an environmentally controlled room was built and seven analytical methods, representing eighteen analytes, were validated. The validations were carried out with smoking machines using a matrix-based approach applying the accuracy profile procedure. The performances of the methods were compared for all three matrices under investigation: background air samples, the environmental aerosol of Tobacco Heating System THS 2.2, a heat-not-burn tobacco product developed by Philip Morris International, and the environmental tobacco smoke of a cigarette. The environmental aerosol generated by the THS 2.2 device did not have any appreciable impact on the performances of the methods. The comparison between the background and THS 2.2 environmental aerosol samples generated by smoking machines showed that only five compounds were higher when THS 2.2 was used in the environmentally controlled room. Regarding environmental tobacco smoke from cigarettes, the yields of all analytes were clearly above those obtained with the other two air sample types. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

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

DOEpatents

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.

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

DOEpatents

Chang, Shih-Ger

1994-01-01

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.

Wet air oxidation pretreatment of biomethanated distillery effluent: mapping pretreatment efficiency in terms color, toxicity reduction and biogas generation.

PubMed

Sarat Chandra, T; Malik, S N; Suvidha, G; Padmere, M L; Shanmugam, P; Mudliar, S N

2014-04-01

The effluents from molasses-based distilleries after biomethanation are beset with problems of intensified dark brown color, high residual COD, low biodegradability index (BOD/COD ratio <0.2) and toxicity issues for possible land application as a potential fertilizer. Wet air oxidation (WAO) pretreatment of biomethanated distillery effluent resulted in substantial enhancement in the biodegradability index (BI) (up to 0.8). WAO pretreated effluent on anaerobic digestion indicated favorable biogas generation with methane content up to 64% along with concomitant COD reduction up to 54.75%. The HPLC analysis indicated that the pretreatment facilitated degradation of major color containing compounds-namely melanoidins, up to 97.8%. The pretreated effluent with enhanced biodegradability along with substantially reduced color also indicated positive effect on seed germination (up to 100%), implying toxicity reduction of the effluent post WAO pretreatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Observations of Tropospheric Carbon Monoxide From the Atmospheric InfraRed Sounder (AIRS): An Alternative Retrieval Scheme and Its Validation.

NASA Astrophysics Data System (ADS)

Douglass, D. H.; Kalnay, E.; Li, H.; Cai, M.

2005-05-01

Carbon monoxide (CO) is present in the troposphere as a product of fossil fuel combustion, biomass burning and the oxidation of volatile hydrocarbons. It is the principal sink of the hydroxyl radical (OH), thereby affecting the concentrations of greenhouse gases such as CH4 and O3. In addition, CO has a lifetime of 1-3 months, making it a good tracer for studying the long range transport of pollution. Satellite observations present a valuable tool in the investigation of tropospheric CO. The Atmospheric InfraRed Sounder (AIRS), onboard the Aqua satellite, is sensitive to tropospheric CO in a number of its 2378 channels. This sensitivity to CO, combined with the daily global coverage provided by AIRS, makes AIRS a potentially useful instrument for observing CO sources and transport. A maximum a posteriori (MAP) retrieval scheme (Rodgers 2000) has been developed for AIRS, to provide CO profiles from near-surface altitudes to around 150 hPa. An extensive validation data set, consisting of over 50 in-situ aircraft CO profiles, has been constructed. This data set combines CO data from a number of independent aircraft campaigns. Results from this validation study and comparisons with the AIRS level 2 CO product will be presented. Rodgers, C. D. (2000), Inverse Methods for Atmospheric Sounding : Theory and Practice, World Scientific, Singapore.

NOVEL MARKERS OF AIR POLLUTION-INDUCED VASCULAR TOXICITY

EPA Science Inventory

The results of this project should be a handful of biological markers that can be subsequently used to: 1) identify susceptible individuals, 2) identify causal components of the complex air pollution mixture, and 3) better understand the biological mechanisms involved in air p...

Clean Air Act Requirements and History

EPA Pesticide Factsheets

In 1970 congress designed the Clean Air Act to combat a variety of air pollution problems, and to tackle emerging pollution threats such as public health, national welfare, toxic air pollutants, acid rain, protection of the ozone layer, and regional haze.

Comprehensive assessment of toxic emissions from coal-fired power plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, T D; Schmidt, C E; Radziwon, A S

1991-01-01

The Pittsburgh Energy Technology Center (PETC) of the US Department of Energy (DOE) has two current investigations, initiated before passage of the Clean Air Act Amendment (CAAA), that will determine the air toxic emissions from coal-fired electric utilities. DOE has contracted with Battelle Memorial Institute and Radian corporation to conduct studies focusing on the potential air toxics, both organic and inorganic, associated with different size fractions of fine particulate matter emitted from power plant stacks. Table 2 indicates the selected analytes to be investigated during these studies. PETC is also developing guidance on the monitoring of Hazardous Air Pollutants (HAPS)more » to be incorporated in the Environmental Monitoring plans for the demonstration projects in its Clean Coal Technology Program.« less

Validation of Air-Backed Underwater Explosion Experiments with ALE3D

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leininger, L D

2005-02-04

This paper summarizes an exercise carried out to validate the process of implementing LLNL's ALE3D to predict the permanent deformation and rupture of an air-backed steel plate subjected to underwater shock. Experiments were performed in a shock tank at the Naval Science and Technology Laboratory in Visakhapatnam India, and the results are documented in reference. A consistent set of air-backed plates is subjected to shocks from increasing weights of explosives ranging from 10g-80g. At 40g and above, rupture is recorded in the experiment and, without fracture mechanics implemented in ALE3D, only the cases of 10g, 20g, and 30g are presentedmore » here. This methodology applies the Jones-Wilkins-Lee (JWL) Equation of State (EOS) to predict the pressure of the expanding detonation products, the Gruneisein EOS for water under highly dynamic compressible flow - both on 1-point integrated 3-d continuum elements. The steel plates apply a bilinear elastic-plastic response with failure and are simulated with 3-point integrated shell elements. The failure for this exercise is based on effective (or equivalent) plastic strain.« less

Validation of a CFD Model by Using 3D Sonic Anemometers to Analyse the Air Velocity Generated by an Air-Assisted Sprayer Equipped with Two Axial Fans

PubMed Central

García-Ramos, F. Javier; Malón, Hugo; Aguirre, A. Javier; Boné, Antonio; Puyuelo, Javier; Vidal, Mariano

2015-01-01

A computational fluid dynamics (CFD) model of the air flow generated by an air-assisted sprayer equipped with two axial fans was developed and validated by practical experiments in the laboratory. The CFD model was developed by considering the total air flow supplied by the sprayer fan to be the main parameter, rather than the outlet air velocity. The model was developed for three air flows corresponding to three fan blade settings and assuming that the sprayer is stationary. Actual measurements of the air velocity near the sprayer were taken using 3D sonic anemometers. The workspace sprayer was divided into three sections, and the air velocity was measured in each section on both sides of the machine at a horizontal distance of 1.5, 2.5, and 3.5 m from the machine, and at heights of 1, 2, 3, and 4 m above the ground The coefficient of determination (R2) between the simulated and measured values was 0.859, which demonstrates a good correlation between the simulated and measured data. Considering the overall data, the air velocity values produced by the CFD model were not significantly different from the measured values. PMID:25621611

Validation of a CFD model by using 3D sonic anemometers to analyse the air velocity generated by an air-assisted sprayer equipped with two axial fans.

PubMed

García-Ramos, F Javier; Malón, Hugo; Aguirre, A Javier; Boné, Antonio; Puyuelo, Javier; Vidal, Mariano

2015-01-22

A computational fluid dynamics (CFD) model of the air flow generated by an air-assisted sprayer equipped with two axial fans was developed and validated by practical experiments in the laboratory. The CFD model was developed by considering the total air flow supplied by the sprayer fan to be the main parameter, rather than the outlet air velocity. The model was developed for three air flows corresponding to three fan blade settings and assuming that the sprayer is stationary. Actual measurements of the air velocity near the sprayer were taken using 3D sonic anemometers. The workspace sprayer was divided into three sections, and the air velocity was measured in each section on both sides of the machine at a horizontal distance of 1.5, 2.5, and 3.5 m from the machine, and at heights of 1, 2, 3, and 4 m above the ground The coefficient of determination (R2) between the simulated and measured values was 0.859, which demonstrates a good correlation between the simulated and measured data. Considering the overall data, the air velocity values produced by the CFD model were not significantly different from the measured values.

Validity of a traffic air pollutant dispersion model to assess exposure to fine particles.

PubMed

Kostrzewa, Aude; Reungoat, Patrice; Raherison, Chantal

2009-08-01

Fine particles (PM(2.5)) are an important component of air pollution. Epidemiological studies have shown health effects due to ambient air particles, particularly allergies in children. Since the main difficulty is to determine exposure to such pollution, traffic air pollutant (TAP) dispersions models have been developed to improve the estimation of individual exposure levels. One such model, the ExTra index, has been validated for nitrogen oxide concentrations but not for other pollutants. The purpose of this study was to assess the validity of the ExTra index to assess PM(2.5) exposure. We compared PM(2.5) concentrations calculated by the ExTra index to reference measures (passive samplers situated under the covered part of the playground), in 15 schools in Bordeaux, in 2000. First, we collected the input data required by the ExTra index: background and local pollution depending on traffic, meteorology and topography. Second, the ExTra index was calculated for each school. Statistical analysis consisted of a graphic description; then, we calculated an intraclass correlation coefficient. Concentrations calculated with the ExTra index and the reference method were similar. The ExTra index underestimated exposure by 2.2 microg m(-3) on average compared to the reference method. The intraclass correlation coefficient was 0.85 and its 95% confidence interval was [0.62; 0.95]. The results suggest that the ExTra index provides an assessment of PM(2.5) exposure similar to that of the reference method. Although caution is required in interpreting these results owing to the small number of sites, the ExTra index could be a useful epidemiological tool for reconstructing individual exposure, an important challenge in epidemiology.

Development and field validation of a community-engaged particulate matter air quality monitoring network in Imperial, California, USA.

PubMed

Carvlin, Graeme N; Lugo, Humberto; Olmedo, Luis; Bejarano, Ester; Wilkie, Alexa; Meltzer, Dan; Wong, Michelle; King, Galatea; Northcross, Amanda; Jerrett, Michael; English, Paul B; Hammond, Donald; Seto, Edmund

2017-12-01

The Imperial County Community Air Monitoring Network was developed as part of a community-engaged research study to provide real-time particulate matter (PM) air quality information at a high spatial resolution in Imperial County, California. The network augmented the few existing regulatory monitors and increased monitoring near susceptible populations. Monitors were both calibrated and field validated, a key component of evaluating the quality of the data produced by the community monitoring network. This paper examines the performance of a customized version of the low-cost Dylos optical particle counter used in the community air monitors compared with both PM 2.5 and PM 10 (particulate matter with aerodynamic diameters <2.5 and <10 μm, respectively) federal equivalent method (FEM) beta-attenuation monitors (BAMs) and federal reference method (FRM) gravimetric filters at a collocation site in the study area. A conversion equation was developed that estimates particle mass concentrations from the native Dylos particle counts, taking into account relative humidity. The R 2 for converted hourly averaged Dylos mass measurements versus a PM 2.5 BAM was 0.79 and that versus a PM 10 BAM was 0.78. The performance of the conversion equation was evaluated at six other sites with collocated PM 2.5 environmental beta-attenuation monitors (EBAMs) located throughout Imperial County. The agreement of the Dylos with the EBAMs was moderate to high (R 2 = 0.35-0.81). The performance of low-cost air quality sensors in community networks is currently not well documented. This paper provides a methodology for quantifying the performance of a next-generation Dylos PM sensor used in the Imperial County Community Air Monitoring Network. This air quality network provides data at a much finer spatial and temporal resolution than has previously been possible with government monitoring efforts. Once calibrated and validated, these high-resolution data may provide more information on

Validation of Mode-S Meteorological Routine Air Report aircraft observations

NASA Astrophysics Data System (ADS)

Strajnar, B.

2012-12-01

The success of mesoscale data assimilation depends on the availability of three-dimensional observations with high spatial and temporal resolution. This paper describes an example of such observations, available through Mode-S air traffic control system composed of ground radar and transponders on board the aircraft. The meteorological information is provided by interrogation of a dedicated meteorological data register, called Meteorological Routine Air Report (MRAR). MRAR provides direct measurements of temperature and wind, but is only returned by a small fraction of aircraft. The quality of Mode-S MRAR data, collected at the Ljubljana Airport, Slovenia, is assessed by its comparison with AMDAR and high-resolution radiosonde data sets, which enable high- and low-level validation, respectively. The need for temporal smoothing of raw Mode-S MRAR data is also studied. The standard deviation of differences between smoothed Mode-S MRAR and AMDAR is 0.35°C for temperature, 0.8 m/s for wind speed and below 10 degrees for wind direction. The differences with respect to radiosondes are larger, with standard deviations of approximately 1.7°C, 3 m/s and 25 degrees for temperature, wind speed and wind direction, respectively. It is concluded that both wind and temperature observations from Mode-S MRAR are accurate and therefore potentially very useful for data assimilation in numerical weather prediction models.

Validation of minicams for measuring concentrations of chemical agent in environmental air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menton, R.G.; Hayes, T.L.; Chou, Y.L.

1993-05-13

Environmental monitoring for chemical agents is necessary to ensure that notification and appropriate action will be taken in the, event that there is a release exceeding control limits of such agents into the workplace outside of engineering controls. Prior to implementing new analytical procedures for environmental monitoring, precision and accuracy (PA) tests are conducted to ensure that an agent monitoring system performs according to specified accuracy, precision, and sensitivity requirements. This testing not only establishes the accuracy and precision of the method, but also determines what factors can affect the method's performance. Performance measures that are particularly important in agentmore » monitoring include the Detection Limit (DL), Decision Limit (DC), Found Action Level (FAL), and the Target Action Level (TAL). PA experiments were performed at Battelle's Medical Research and Evaluation Facility (MREF) to validate the use of the miniature chemical agent monitoring system (MINICAMs) for measuring environmental air concentrations of sulfur mustard (HD). This presentation discusses the experimental and statistical approaches for characterizing the performance of MINICAMS for measuring HD in air.« less

Air Toxics Under the Big Sky: Examining the Effectiveness of Authentic Scientific Research on High School Students' Science Skills and Interest.

PubMed

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. A quasi-experimental design was used in order to understand: 1) how the program affects student understanding of scientific inquiry and research and 2) how the open inquiry learning opportunities provided by the program increase student interest in science as a career path . Treatment students received instruction related to air pollution (airborne particulate matter), associated health concerns, and training on how to operate air quality testing equipment. They then participated in a yearlong scientific research project in which they developed and tested hypotheses through research of their own design regarding the sources and concentrations of air pollution in their homes and communities. Results from an external evaluation revealed that treatment students developed a deeper understanding of scientific research than did comparison students, as measured by their ability to generate good hypotheses and research designs, and equally expressed an increased interest in pursuing a career in science. These results emphasize the value of and need for authentic science learning opportunities in the modern science classroom.

Air Toxics Under the Big Sky: examining the effectiveness of authentic scientific research on high school students' science skills and interest

NASA Astrophysics Data System (ADS)

Ward, Tony J.; Delaloye, Naomi; Adams, Earle Raymond; Ware, Desirae; Vanek, Diana; Knuth, Randy; Hester, Carolyn Laurie; Marra, Nancy Noel; Holian, Andrij

2016-04-01

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) how the program affects student understanding of scientific inquiry and research and (2) how the open-inquiry learning opportunities provided by the program increase student interest in science as a career path. Treatment students received instruction related to air pollution (airborne particulate matter), associated health concerns, and training on how to operate air quality testing equipment. They then participated in a yearlong scientific research project in which they developed and tested hypotheses through research of their own design regarding the sources and concentrations of air pollution in their homes and communities. Results from an external evaluation revealed that treatment students developed a deeper understanding of scientific research than did comparison students, as measured by their ability to generate good hypotheses and research designs, and equally expressed an increased interest in pursuing a career in science. These results emphasize the value of and need for authentic science learning opportunities in the modern science classroom.

Air Toxics Under the Big Sky: Examining the Effectiveness of Authentic Scientific Research on High School Students’ Science Skills and Interest

PubMed Central

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. A quasi-experimental design was used in order to understand: 1) how the program affects student understanding of scientific inquiry and research and 2) how the open inquiry learning opportunities provided by the program increase student interest in science as a career path. Treatment students received instruction related to air pollution (airborne particulate matter), associated health concerns, and training on how to operate air quality testing equipment. They then participated in a yearlong scientific research project in which they developed and tested hypotheses through research of their own design regarding the sources and concentrations of air pollution in their homes and communities. Results from an external evaluation revealed that treatment students developed a deeper understanding of scientific research than did comparison students, as measured by their ability to generate good hypotheses and research designs, and equally expressed an increased interest in pursuing a career in science. These results emphasize the value of and need for authentic science learning opportunities in the modern science classroom. PMID:28286375

Validation of air displacement plethysmography for assessing body composition.

PubMed

Wagner, D R; Heyward, V H; Gibson, A L

2000-07-01

The purpose of this study was to verify the validity of an air displacement plethysmography device (Bod Pod) for estimating body density (Db). The Db from the Bod Pod (DbBP) was compared with the Db from hydrostatic weighing (DbHW) at residual lung volume in a heterogeneous sample of 30 black men who varied in age (32.0 +/- 7.7 yr), height (180.3 +/- 7.5 cm), body mass (84.2 +/- 15.0 kg), body fatness (16.1 +/- 7.5%), and self-reported physical activity level and socioeconomic status. The Db for each method was converted to relative body fat (%BF) using race-specific conversion formulas and subsequently compared with %BF obtained from dual-energy x-ray absorptiometry (%BFDXA). Linear regression, using DbHW as the dependent variable and DbBP as the predictor, produced an R2 = 0.84 and SEE = 0.00721 g x cc(-1). However, the mean difference between the two methods (0.00450 +/- 0.00718 g x cc(-1) was significant (P < 0.01). The Bod Pod underestimated the Db of 73% of the sample. The %BF estimates from the Bod Pod, HW, and DXA differed significantly (P < 0.01). The average %BFBP (17.7 +/- 7.4%) was significantly greater than %BFHW (15.8 +/- 7.5%) and %BFDXA (16.1 +/- 7.5%); however, there was no significant difference between %BFHW and %BFDXA. The Bod Pod significantly and systematically underestimated Db, resulting in an overestimation of %BF. More cross-validation research is needed before recommending the Bod Pod as a reference method.

AIR QUALITY MODELING AT COARSE-TO-FINE SCALES IN URBAN AREAS

EPA Science Inventory

Urban air toxics control strategies are moving towards a community based modeling approach, with an emphasis on assessing those areas that experience high air toxic concentration levels, the so-called "hot spots". This approach will require information that accurately maps and...

ENGINEERING BULLETIN: AIR PATHWAY ANALYSIS

EPA Science Inventory

This bulletin presents information on estimating toxic air emissions from Superfund sites. The focus is on the collection of air emmissions data during the site inspection and remedial investigation/feasibility study and the use of these data for the selection or implementation o...

Analysis of Air Toxics From NOAA WP-3 Aircraft Measurements During the TexAQS 2006 Campaign: Comparison With Emission Inventories and Additive Inhalation Risk Factors

NASA Astrophysics Data System (ADS)

Del Negro, L. A.; Warneke, C.; de Gouw, J. A.; Atlas, E.; Lueb, R.; Zhu, X.; Pope, L.; Schauffler, S.; Hendershot, R.; Washenfelder, R.; Fried, A.; Richter, D.; Walega, J. G.; Weibring, P.

2007-12-01

Benzene and nine other air toxics classified as human carcinogens by the International Agency for Research on Cancer (IARC) were measured from the NOAA WP-3 aircraft during the TexAQS 2006 campaign. In-situ measurements of benzene, measured with a PTR-MS instrument, are used to estimate emission fluxes for comparison with point source emission inventories developed by the Texas Commission on Environmental Quality. Mean and median mixing ratios for benzene, acetaldehyde, formaldehyde, 1,3-butadiene, carbon tetrachloride, chloroform, 1,2-dichloroethane, dibromoethane, dichloromethane, and vinyl chloride, encountered over the city of Houston during the campaign, are combined with inhalation unit risk factor values developed by the California Environmental Protection Agency and the United States Environmental Protection Agency to estimate the additive inhalation risk factor. This additive risk factor represents the risk associated with lifetime (70 year) exposure at the levels measured and should not be used as an absolute indicator of risk to individuals. However, the results are useful for assessments of changing relative risk over time, and for identifying dominant contributions to the overall air toxic risk.

Three Dimensional Vapor Intrusion Modeling: Model Validation and Uncertainty Analysis

NASA Astrophysics Data System (ADS)

Akbariyeh, S.; Patterson, B.; Rakoczy, A.; Li, Y.

2013-12-01

Volatile organic chemicals (VOCs), such as chlorinated solvents and petroleum hydrocarbons, are prevalent groundwater contaminants due to their improper disposal and accidental spillage. In addition to contaminating groundwater, VOCs may partition into the overlying vadose zone and enter buildings through gaps and cracks in foundation slabs or basement walls, a process termed vapor intrusion. Vapor intrusion of VOCs has been recognized as a detrimental source for human exposures to potential carcinogenic or toxic compounds. The simulation of vapor intrusion from a subsurface source has been the focus of many studies to better understand the process and guide field investigation. While multiple analytical and numerical models were developed to simulate the vapor intrusion process, detailed validation of these models against well controlled experiments is still lacking, due to the complexity and uncertainties associated with site characterization and soil gas flux and indoor air concentration measurement. In this work, we present an effort to validate a three-dimensional vapor intrusion model based on a well-controlled experimental quantification of the vapor intrusion pathways into a slab-on-ground building under varying environmental conditions. Finally, a probabilistic approach based on Monte Carlo simulations is implemented to determine the probability distribution of indoor air concentration based on the most uncertain input parameters.

1990 Clean Air Act Amendment Summary: Title I

EPA Pesticide Factsheets

This page provides an overview of the 1990 amendments to Title I of the Clean Air Act, which were enacted to curb acid rain, urban air pollution and toxic air emissions. The edits to this title deal with the national ambient air quality standards.

Propulsion Risk Reduction Activities for Non-Toxic Cryogenic Propulsion

NASA Technical Reports Server (NTRS)

Smith, Timothy D.; Klem, Mark D.; Fisher, Kenneth

2010-01-01

The Propulsion and Cryogenics Advanced Development (PCAD) Project s primary objective is to develop propulsion system technologies for non-toxic or "green" propellants. The PCAD project focuses on the development of non-toxic propulsion technologies needed to provide necessary data and relevant experience to support informed decisions on implementation of non-toxic propellants for space missions. Implementation of non-toxic propellants in high performance propulsion systems offers NASA an opportunity to consider other options than current hypergolic propellants. The PCAD Project is emphasizing technology efforts in reaction control system (RCS) thruster designs, ascent main engines (AME), and descent main engines (DME). PCAD has a series of tasks and contracts to conduct risk reduction and/or retirement activities to demonstrate that non-toxic cryogenic propellants can be a feasible option for space missions. Work has focused on 1) reducing the risk of liquid oxygen/liquid methane ignition, demonstrating the key enabling technologies, and validating performance levels for reaction control engines for use on descent and ascent stages; 2) demonstrating the key enabling technologies and validating performance levels for liquid oxygen/liquid methane ascent engines; and 3) demonstrating the key enabling technologies and validating performance levels for deep throttling liquid oxygen/liquid hydrogen descent engines. The progress of these risk reduction and/or retirement activities will be presented.

Steam-air blown bubbling fluidized bed biomass gasification (BFBBG): Multi-scale models and experimental validation

DOE PAGES

Bates, Richard B.; Ghoniem, Ahmed F.; Jablonski, Whitney S.; ...

2017-02-02

During fluidized bed biomass gasification, complex gas-solid mixing patterns and numerous chemical and physical phenomena make identification of optimal operating conditions challenging. In this work, a parametric experimental campaign was carried out alongside the development of a coupled reactor network model which successfully integrates the individually validated sub-models to predict steady-state reactor performance metrics and outputs. The experiments utilized an integrated gasification system consisting of an externally-heated, bench-scale, 4-in., 5 kWth, fluidized bed steam/air blown gasifier fed with woody biomass equipped with a molecular beam mass spectrometer to directly measure tar species. The operating temperature (750-850°C) and air/fuel equivalence ratiomore » (ER = 0-0.157) were independently varied to isolate their effects. Elevating temperature is shown to improve the char gasification rate and reduce tar concentrations. In conclusion, air strongly impacts the composition of tar, accelerating the conversion of lighter polycyclic-aromatic hydrocarbons into soot precursors, while also improving the overall carbon conversion.« less

40 CFR 80.1005 - What acts are prohibited under the gasoline toxics program?

Code of Federal Regulations, 2010 CFR

2010-07-01

... gasoline toxics program? 80.1005 Section 80.1005 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Violation Provisions § 80.1005 What acts are prohibited under the gasoline toxics program? No person shall: (a...

40 CFR 80.1005 - What acts are prohibited under the gasoline toxics program?

Code of Federal Regulations, 2011 CFR

2011-07-01

... gasoline toxics program? 80.1005 Section 80.1005 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Violation Provisions § 80.1005 What acts are prohibited under the gasoline toxics program? No person shall: (a...

40 CFR 80.1005 - What acts are prohibited under the gasoline toxics program?

Code of Federal Regulations, 2012 CFR

2012-07-01

... gasoline toxics program? 80.1005 Section 80.1005 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Violation Provisions § 80.1005 What acts are prohibited under the gasoline toxics program? No person shall: (a...

40 CFR 80.1005 - What acts are prohibited under the gasoline toxics program?

Code of Federal Regulations, 2014 CFR

2014-07-01

... gasoline toxics program? 80.1005 Section 80.1005 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Violation Provisions § 80.1005 What acts are prohibited under the gasoline toxics program? No person shall: (a...

40 CFR 80.1005 - What acts are prohibited under the gasoline toxics program?

Code of Federal Regulations, 2013 CFR

2013-07-01

... gasoline toxics program? 80.1005 Section 80.1005 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Violation Provisions § 80.1005 What acts are prohibited under the gasoline toxics program? No person shall: (a...

Comparison of the contributions of polychlorinated dibenzo-p-dioxins and dibenzofurans and other unintentionally produced persistent organic pollutants to the total toxic equivalents in air of steel plant areas.

PubMed

Li, Sumei; Liu, Guorui; Zheng, Minghui; Liu, Wenbin; Wang, Mei; Xiao, Ke; Li, Changliang; Wang, Yiwen

2015-05-01

The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and the "dioxin-like" (dl) compounds polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), polybrominated dibenzo-p-dioxins (PBDDs), and dibenzofurans (PBDFs), were determined in the air samples collected from six steel plants. The toxic equivalent (TEQ) concentrations of the PCDDs, PCDFs, dl-PCBs, dl-PCNs, PBDDs, and PBDFs in the air were 0.01-0.19 pg WHO-TEQ Nm(-3), 0.01-0.69 pg WHO-TEQN m(-3), 0.001-0.089 pg WHO-TEQ Nm(-3), 0.002-0.011 pg TEQ Nm(-3), 0.004-0.02 pg TEQ Nm(-3), and 0.02-0.12 pg TEQ Nm(-3), respectively. The PCNs were the most abundant compounds (by mass concentration), contributing about 87% of the total mass concentrations of the analytes that were found in the air of the steel plant areas. The PCDFs contributed about 47% of the total TEQs, following by the PBDFs (28%) and the PCDDs (18%). The dioxin-like compounds together contributed up to 40% of the total TEQs, so their contributions to the toxic effects that could be caused by exposure to the air of the steel plant areas were significant. The congener profiles in the air were similar to the congener profiles that were found in stack gas emissions, indicating that the steelmaking plants were possible sources of the PCDDs, PCDFs, and dioxin-like compounds that were found in the air of the steel plant areas. Copyright © 2015 Elsevier Ltd. All rights reserved.

Air conditioning systems as non-infectious health hazards inducing acute respiratory symptoms.

PubMed

Gerber, Alexander; Fischer, Axel; Willig, Karl-Heinz; Groneberg, David A

2006-04-01

Chronic and acute exposure to toxic aerosols belongs to frequent causes of airway diseases. However, asthma attacks due to long-distance inhalative exposure to organic solvents, transmitted via an air condition system, have not been reported so far. The present case illustrates the possibility of air conditioning systems as non-infectious health hazards in occupational medicine. So far, only infectious diseases such as legionella pneumophila pneumonia have commonly been associated to air-conditioning exposures but physicians should be alert to the potential of transmission of toxic volatile substances via air conditioning systems. In view of the events of the 11th of September 2001 with a growing danger of large building terrorism which may even use air conditioning systems to transmit toxins, facility management security staff should be alerted to possible non-infectious toxic health hazards arising from air-conditioning systems.

QSAR Modeling of Rat Acute Toxicity by Oral Exposure

PubMed Central

Zhu, Hao; Martin, Todd M.; Ye, Lin; Sedykh, Alexander; Young, Douglas M.; Tropsha, Alexander

2009-01-01

Few Quantitative Structure-Activity Relationship (QSAR) studies have successfully modeled large, diverse rodent toxicity endpoints. In this study, a comprehensive dataset of 7,385 compounds with their most conservative lethal dose (LD50) values has been compiled. A combinatorial QSAR approach has been employed to develop robust and predictive models of acute toxicity in rats caused by oral exposure to chemicals. To enable fair comparison between the predictive power of models generated in this study versus a commercial toxicity predictor, TOPKAT (Toxicity Prediction by Komputer Assisted Technology), a modeling subset of the entire dataset was selected that included all 3,472 compounds used in the TOPKAT’s training set. The remaining 3,913 compounds, which were not present in the TOPKAT training set, were used as the external validation set. QSAR models of five different types were developed for the modeling set. The prediction accuracy for the external validation set was estimated by determination coefficient R2 of linear regression between actual and predicted LD50 values. The use of the applicability domain threshold implemented in most models generally improved the external prediction accuracy but expectedly led to the decrease in chemical space coverage; depending on the applicability domain threshold, R2 ranged from 0.24 to 0.70. Ultimately, several consensus models were developed by averaging the predicted LD50 for every compound using all 5 models. The consensus models afforded higher prediction accuracy for the external validation dataset with the higher coverage as compared to individual constituent models. The validated consensus LD50 models developed in this study can be used as reliable computational predictors of in vivo acute toxicity. PMID:19845371

Validation of an LDH Assay for Assessing Nanoparticle Toxicity

PubMed Central

Han, Xianglu; Gelein, Robert; Corson, Nancy; Wade-Mercer, Pamela; Jiang, Jingkun; Biswas, Pratim; Finkelstein, Jacob N.; Elder, Alison; Oberdörster, Günter

2014-01-01

Studies showed that certain cytotoxicity assays were not suitable for assessing nanoparticle (NP) toxicity. We evaluated a lactate dehydrogenase (LDH) assay for assessing copper (Cu-40, 40 nm), silver (Ag-35, 35 nm; Ag-40, 40 nm), and titanium dioxide (TiO2-25, 25 nm) NPs by examining their potential to inactivate LDH and interference with β-nicotinamide adenine dinucleotide (NADH), a substrate for the assay. We also performed a dissolution assay for some of the NPs. We found that the copper NPs, because of their high dissolution rate, could interfere with the LDH assay by inactivating LDH. Ag-35 could also inactivate LDH probably because of the carbon matrix used to cage the particles during synthesis. TiO2-25 NPs were found to adsorb LDH molecules. In conclusion, NP interference with the LDH assay depends on the type of NPs and the suitability of the assay for assessing NP toxicity should be examined case by case. PMID:21722700

The comparative toxicity of operational Air Force hydraulic fluids.

PubMed

Mattie, D R; Hoeflich, T J; Jones, C E; Horton, M L; Whitmire, R E; Godin, C S; Flemming, C D; Andersen, M E

1993-01-01

The subchronic (26 day) oral toxicities of two AF hydraulic fluids (MIL-H-5606 [H5], MIL-H-83282 [H8]), a commercial phosphate ester (PE), and two candidate hydraulic fluids (low temperature version of MIL-H-83282 [LT] and chlorotrifluorethylene oligomers [polyCTFE]) were compared in male F-344 rats. Oral dosing was used in order to quickly compare these fluids to PolyCTFE, the only fluid at the time to have been tested in a 90-day inhalation study. Rats were initially dosed with 1.0 g/kg/day of each fluid. H8 increased alkaline phosphatase (ALKP) while LT produced an anemia and leukocytosis. Exposure to H5 fluid resulted in lymphocytopenia and persistent diuresis. Due to their greater toxicity, resulting in lethality in the first dosing study, only 0.5 g/kg/day of PE and PolyCTFE were administered in the second study. Exposure to PE (0.5 g/kg) resulted in an anemia and decreases in BW (day 10 until day 25), spleen/BW ratio, blood urea nitrogen (BUN), and creatinine (CREAT). PolyCREAT (0.5 g/kg) decreased BW (day 11 to the end of the study) and testicular weight. PolyCTFE (0.5 g/kg) increased relative spleen weights, various clinical chemistry parameters, and triggered a reversible diuresis. PolyCTFE (0.5 g/kg), PE (0.5 g/kg), and H5 produced an increase in absolute and relative liver weights compared to control livers. Peroxisomal beta oxidation, an indicator of peroxisomal proliferation, was significantly increased above control levels in the livers of all rats except the PE (0.5 g/kg) group, where the increase was not significant. Hydrocarbon nephropathy, indicated by increased levels of hyaline droplets in kidney tubules, was severe in H5, mild in H8, LT, and PolyCTFE (0.5 g/kg), and minimal in PE (0.5 g/kg). The MIL-H-83282 fluids (H8 and LT) were the least toxic hydraulic fluids. PolyCTFE and PE were the most toxic, with H5 intermediate.

Assessment of Sociodemographic and Geographic Disparities in Cancer Risk from Air Toxics in South Carolina

PubMed Central

Wilson, Sacoby; Burwell-Naney, Kristen; Jiang, Chengsheng; Zhang, Hongmei; Samantapudi, Ashok; Murray, Rianna; Dalemarre, Laura; Rice, LaShanta; Williams, Edith

2015-01-01

Populations of color and low-income communities are often disproportionately burdened by exposures to various environmental contaminants, including air pollution. Some air pollutants have carcinogenic properties that are particularly problematic in South Carolina (SC), a state that consistently has high rates of cancer mortality for all sites. The purpose of this study was to assess cancer risk disparities in SC by linking risk estimates from the U.S. Environmental Protection Agency’s 2005 National Air Toxics Assessment (NATA) with sociodemographic data from the 2000 US Census Bureau. Specifically, NATA risk data for varying risk categories were linked by tract ID and analyzed with sociodemographic variables from the 2000 census using R. The average change in cancer risk from all sources by sociodemographic variable was quantified using multiple linear regression models. Spatial methods were further employed using ArcGIS 10 to assess the distribution of all source risk and percent non-white at each census tract level. The relative risk estimates of the proportion of high cancer risk tracts (defined as the top 10% of cancer risk in SC) and their respective 95% confidence intervals (CIs) were calculated between the first and latter three quartiles defined by sociodemographic factors, while the variance in the percentage of high cancer risk between quartile groups was tested using Pearson’s chi-square. The average total cancer risk for SC was 26.8 people/million (ppl/million). The risk from on-road sources was approximately 5.8 ppl/million, higher than the risk from major, area, and non-road sources (1.8, 2.6, and 1.3 ppl/million), respectively. Based on our findings, addressing on-road sources may decrease the disproportionate cancer risk burden among low-income populations and communities of color in SC. PMID:26037107

U.S. EPA Environmental Quality Index - Air Domain

EPA Science Inventory

This is an invited presentation by Region 5, Air Office, who asked me to provide an overview of the Air Domain and health results associated with the Air Domain of the Environmental Quality Index. Region 5 is hosting an Air Toxics meeting for its member states (Ohio, Michigan, I...

A Supersonic Argon/Air Coaxial Jet Experiment for Computational Fluid Dynamics Code Validation

NASA Technical Reports Server (NTRS)

Clifton, Chandler W.; Cutler, Andrew D.

2007-01-01

A non-reacting experiment is described in which data has been acquired for the validation of CFD codes used to design high-speed air-breathing engines. A coaxial jet-nozzle has been designed to produce pressure-matched exit flows of Mach 1.8 at 1 atm in both a center jet of argon and a coflow jet of air, creating a supersonic, incompressible mixing layer. The flowfield was surveyed using total temperature, gas composition, and Pitot probes. The data set was compared to CFD code predictions made using Vulcan, a structured grid Navier-Stokes code, as well as to data from a previous experiment in which a He-O2 mixture was used instead of argon in the center jet of the same coaxial jet assembly. Comparison of experimental data from the argon flowfield and its computational prediction shows that the CFD produces an accurate solution for most of the measured flowfield. However, the CFD prediction deviates from the experimental data in the region downstream of x/D = 4, underpredicting the mixing-layer growth rate.

1990 Clean Air Act Amendment Summary: Title II

EPA Pesticide Factsheets

This page provides an overview of the 1990 amendments to Title II of the Clean Air Act, which were enacted to curb acid rain, urban air pollution and toxic air emissions. The edits to this title deal emissions from mobile sources.

1990 Clean Air Act Amendment Summary: Title IV

EPA Pesticide Factsheets

This page provides an overview of the 1990 amendments to Title IV of the Clean Air Act, which were enacted to curb acid rain, urban air pollution and toxic air emissions. The edits to this title deal with acid deposition control.

1990 Clean Air Act Amendment Summary: Title VII

EPA Pesticide Factsheets

This page provides an overview of the 1990 amendments to Title VII of the Clean Air Act, which were enacted to curb acid rain, urban air pollution and toxic air emissions. The edits to this title deal with enforcement provisions.

Feasibility of an Air Liaison Officer Career Field: Improving the Theater Air-Ground System

DTIC Science & Technology

2008-01-01

for Plans and Operations ALO air liaison officer AMLO air mobility liaison officer ANG Air National Guard ASOC air support operations center ASOG air...liaison officers ( AMLOs ) to liaison elements at Army corps, division, and other jointly validated headquarters to provide air mobility liaison. 1

Development and Validation of a Collocated Exposure Monitoring Methodology using Portable Air Monitors

NASA Astrophysics Data System (ADS)

Li, Z.; Che, W.; Frey, H. C.; Lau, A. K. H.

2016-12-01

Portable air monitors are currently being developed and used to enable a move towards exposure monitoring as opposed to fixed site monitoring. Reliable methods are needed regarding capturing spatial and temporal variability in exposure concentration to obtain credible data from which to develop efficient exposure mitigation measures. However, there are few studies that quantify the validity and repeatability of the collected data. The objective of this study is to present and evaluate a collocated exposure monitoring (CEM) methodology including the calibration of portable air monitors against stationary reference equipment, side-by-side comparison of portable air monitors, personal or microenvironmental exposure monitoring and the processing and interpretation of the collected data. The CEM methodology was evaluated based on application to portable monitors TSI DustTrak II Aerosol Monitor 8530 for fine particulate matter (PM2.5) and TSI Q-Trak model 7575 with probe model 982 for CO, CO2, temperature and relative humidity. Taking a school sampling campaign in Hong Kong in January and June, 2015 as an example, the calibrated side-by-side measured 1 Hz PM2.5 concentrations showed good consistency between two sets of portable air monitors. Confidence in side-by-side comparison, PM2.5 concentrations of which most of the time were within 2 percent, enabled robust inference regarding differences when the monitors measured in classroom and pedestrian during school hour. The proposed CEM methodology can be widely applied in sampling campaigns with the objective of simultaneously characterizing pollutant concentrations in two or more locations or microenvironments. The further application of the CEM methodology to transportation exposure will be presented and discussed.

Foliage Plants for Improving Indoor Air Quality

NASA Technical Reports Server (NTRS)

Wolverton, B. C.

1988-01-01

NASA's research with foliage houseplants during the past 10 years has produced a new concept in indoor air quality improvement. This new and exciting technology is quite simple. Both plant leaves and roots are utilized in removing trace levels of toxic vapors from inside tightly sealed buildings. Low levels of chemicals such as carbon monoxide and formaldehyde can be removed from indoor environments by plant leaves alone, while higher concentrations of numerous toxic chemicals can be removed by filtering indoor air through the plant roots surrounded by activated carbon. The activated carbon absorbs large quantities of the toxic chemicals and retains them until the plant roots and associated microorganisms degrade and assimilate these chemicals.

Exposure information in environmental health research: Current opportunities and future directions for particulate matter, ozone, and toxic air pollutants

DOE Office of Scientific and Technical Information (OSTI.GOV)

McKone, Thomas E.; Ryan, P. Barry; Ozkaynak, Haluk

2007-02-01

Understanding and quantifying outdoor and indoor sources of human exposure are essential but often not adequately addressed in health-effects studies for air pollution. Air pollution epidemiology, risk assessment, health tracking and accountability assessments are examples of health-effects studies that require but often lack adequate exposure information. Recent advances in exposure modeling along with better information on time-activity and exposure factors data provide us with unique opportunities to improve the assignment of exposures for both future and ongoing studies linking air pollution to health impacts. In September 2006, scientists from the US Environmental Protection Agency (EPA) and the Centers for Diseasemore » Control and Prevention (CDC) along with scientists from the academic community and state health departments convened a symposium on air pollution exposure and health in order to identify, evaluate, and improve current approaches for linking air pollution exposures to disease. This manuscript presents the key issues, challenges and recommendations identified by the exposure working group, who used cases studies of particulate matter, ozone, and toxic air pollutant exposure to evaluate health-effects for air pollution. One of the over-arching lessons of this workshop is that obtaining better exposure information for these different health-effects studies requires both goal-setting for what is needed and mapping out the transition pathway from current capabilities to meeting these goals. Meeting our long-term goals requires definition of incremental steps that provide useful information for the interim and move us toward our long-term goals. Another over-arching theme among the three different pollutants and the different health study approaches is the need for integration among alternate exposure assessment approaches. For example, different groups may advocate exposure indicators, biomonitoring, mapping methods (GIS), modeling, environmental

Analytical techniques and method validation for the measurement of selected semivolatile and nonvolatile organofluorochemicals in air.

PubMed

Reagen, William K; Lindstrom, Kent R; Thompson, Kathy L; Flaherty, John M

2004-09-01

The widespread use of semi- and nonvolatile organofluorochemicals in industrial facilities, concern about their persistence, and relatively recent advancements in liquid chromatography/mass spectrometry (LC/MS) technology have led to the development of new analytical methods to assess potential worker exposure to airborne organofluorochemicals. Techniques were evaluated for the determination of 19 organofluorochemicals and for total fluorine in ambient air samples. Due to the potential biphasic nature of most of these fluorochemicals when airborne, Occupational Safety and Health Administration (OSHA) versatile sampler (OVS) tubes were used to simultaneously trap fluorochemical particulates and vapors from workplace air. Analytical methods were developed for OVS air samples to quantitatively analyze for total fluorine using oxygen bomb combustion/ion selective electrode and for 17 organofluorochemicals using LC/MS and gas chromatography/mass spectrometry (GC/MS). The experimental design for this validation was based on the National Institute of Occupational Safety and Health (NIOSH) Guidelines for Air Sampling and Analytical Method Development and Evaluation, with some revisions of the experimental design. The study design incorporated experiments to determine analytical recovery and stability, sampler capacity, the effect of some environmental parameters on recoveries, storage stability, limits of detection, precision, and accuracy. Fluorochemical mixtures were spiked onto each OVS tube over a range of 0.06-6 microg for each of 12 compounds analyzed by LC/MS and 0.3-30 microg for 5 compounds analyzed by GC/MS. These ranges allowed reliable quantitation at 0.001-0.1 mg/m3 in general for LC/MS analytes and 0.005-0.5 mg/m3 for GC/MS analytes when 60 L of air are sampled. The organofluorochemical exposure guideline (EG) is currently 0.1 mg/m3 for many analytes, with one exception being ammonium perfluorooctanoate (EG is 0.01 mg/m3). Total fluorine results may be used

Formaldehyde: a candidate toxic air contaminant. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.

Use of Segregation Indices, Townsend Index, and Air Toxics Data to Assess Lifetime Cancer Risk Disparities in Metropolitan Charleston, South Carolina, USA

PubMed Central

Rice, LaShanta J.; Jiang, Chengsheng; Wilson, Sacoby M.; Burwell-Naney, Kristen; Samantapudi, Ashok; Zhang, Hongmei

2014-01-01

Background: Studies have demonstrated a relationship between segregation and level of education, occupational opportunities, and risk behaviors, yet a paucity of research has elucidated the association between racial residential segregation, socioeconomic deprivation, and lifetime cancer risk. Objectives: We examined estimated lifetime cancer risk from air toxics by racial composition, segregation, and deprivation in census tracts in Metropolitan Charleston. Methods: Segregation indices were used to measure the distribution of groups of people from different races within neighborhoods. The Townsend Index was used to measure economic deprivation in the study area. Poisson multivariate regressions were applied to assess the association of lifetime cancer risk with segregation indices and Townsend Index along with several sociodemographic measures. Results: Lifetime cancer risk from all pollution sources was 28 persons/million for half of the census tracts in Metropolitan Charleston. Isolation Index and Townsend Index both showed significant correlation with lifetime cancer risk from different sources. This significance still holds after adjusting for other sociodemographic measures in a Poisson regression, and these two indices have stronger effect on lifetime cancer risk compared to the effects of sociodemographic measures. Conclusions: We found that material deprivation, measured by the Townsend Index and segregation measured by the Isolation index, introduced high impact on lifetime cancer risk by air toxics at the census tract level. PMID:24852759

40 CFR 80.1015 - Who is liable for violations under the gasoline toxics program?

Code of Federal Regulations, 2013 CFR

2013-07-01

... gasoline toxics program? 80.1015 Section 80.1015 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Violation Provisions § 80.1015 Who is liable for violations under the gasoline toxics program? (a) Persons liable for...

40 CFR 80.1015 - Who is liable for violations under the gasoline toxics program?

Code of Federal Regulations, 2012 CFR

2012-07-01

... gasoline toxics program? 80.1015 Section 80.1015 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Violation Provisions § 80.1015 Who is liable for violations under the gasoline toxics program? (a) Persons liable for...

40 CFR 80.810 - Who shall register with EPA under the gasoline toxics program?

Code of Federal Regulations, 2010 CFR

2010-07-01

... gasoline toxics program? 80.810 Section 80.810 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics General Information § 80.810 Who shall register with EPA under the gasoline toxics program? (a) Refiners and importers...

40 CFR 80.1015 - Who is liable for violations under the gasoline toxics program?

Code of Federal Regulations, 2014 CFR

2014-07-01

... gasoline toxics program? 80.1015 Section 80.1015 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Violation Provisions § 80.1015 Who is liable for violations under the gasoline toxics program? (a) Persons liable for...

40 CFR 80.810 - Who shall register with EPA under the gasoline toxics program?

Code of Federal Regulations, 2012 CFR

2012-07-01

... gasoline toxics program? 80.810 Section 80.810 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics General Information § 80.810 Who shall register with EPA under the gasoline toxics program? (a) Refiners and importers...

40 CFR 80.1015 - Who is liable for violations under the gasoline toxics program?

Code of Federal Regulations, 2010 CFR

2010-07-01

... gasoline toxics program? 80.1015 Section 80.1015 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Violation Provisions § 80.1015 Who is liable for violations under the gasoline toxics program? (a) Persons liable for...

40 CFR 80.810 - Who shall register with EPA under the gasoline toxics program?

Code of Federal Regulations, 2011 CFR

2011-07-01

... gasoline toxics program? 80.810 Section 80.810 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics General Information § 80.810 Who shall register with EPA under the gasoline toxics program? (a) Refiners and importers...

40 CFR 80.810 - Who shall register with EPA under the gasoline toxics program?

Code of Federal Regulations, 2013 CFR

2013-07-01

... gasoline toxics program? 80.810 Section 80.810 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics General Information § 80.810 Who shall register with EPA under the gasoline toxics program? (a) Refiners and importers...

40 CFR 80.810 - Who shall register with EPA under the gasoline toxics program?

Code of Federal Regulations, 2014 CFR

2014-07-01

... gasoline toxics program? 80.810 Section 80.810 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics General Information § 80.810 Who shall register with EPA under the gasoline toxics program? (a) Refiners and importers...

40 CFR 80.1015 - Who is liable for violations under the gasoline toxics program?

Code of Federal Regulations, 2011 CFR

2011-07-01

... gasoline toxics program? 80.1015 Section 80.1015 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Violation Provisions § 80.1015 Who is liable for violations under the gasoline toxics program? (a) Persons liable for...

Thermal Stress and Toxicity | Science Inventory | US EPA

EPA Pesticide Factsheets

Elevating ambient temperature above thermoneutrality exacerbates toxicity of most air pollutants, insecticides, and other toxic chemicals. On the other hand, safety and toxicity testing of toxicants and drugs is usually performed in mice and rats maintained at subthermoneutral temperatures of —22 °C. When exposed to chemical toxicants under these relatively cool conditions, rodents typically undergo a regulated hypothermic response, characterized by preference for cooler ambient temperatures and controlled reduction in core temperature. Reducing core temperature delays the clearance of most toxicants from the body; however, a mild hypothermia also improves recovery and survival from the toxicant. Raising ambient temperature to thermoneutrality and above increases the rate of clearance of the toxicant but also exacerbates toxicity. Furthermore, heat stress combined with work or exercise is likely to worsen toxicity. Body temperature of large mammals, including humans, does not decrease as much in response to exposure to a toxicant. However, heat stress tan nonetheless worsen toxic outcome in humans through a variety of mechanisms. For example, heat-induced sweating and elevation in skin blood flow accelerates uptake of some insecticides. Epidemiological studies suggest that thermal stress may exacerbate the toxicity of airborne pollutants such as ozone and particulate matter. Overall, translating results of studies in rodents to that of humans is a formidable

Analytical method validation for the determination of 2,3,3,3-tetrafluoropropene in air samples using gas chromatography with flame ionization detection.

PubMed

Mawn, Michael P; Kurtz, Kristine; Stahl, Deborah; Chalfant, Richard L; Koban, Mary E; Dawson, Barbara J

2013-01-01

A new low global warming refrigerant, 2,3,3,3-tetrafluoro propene, or HFO-1234yf, has been successfully evaluated for automotive air conditioning, and is also being evaluated for stationary refrigeration and air conditioning systems. Due to the advantageous environmental properties of HFO-1234yf versus HFC-134a, coupled with its similar physical properties and system performance, HFO-1234yf is also being evaluated to replace HFC-134a in refrigeration applications where neat HFC-134a is currently used. This study reports on the development and validation of a sampling and analytical method for the determination of HFO-1234yf in air. Different collection media were screened for desorption and simulated sampling efficiency with three-section (350/350/350 mg) Anasorb CSC showing the best results. Therefore, air samples were collected using two 3-section Anasorb CSC sorbent tubes in series at 0.02 L/min for up to 8 hr for sample volumes of up to 9.6 L. The sorbent tubes were extracted in methylene chloride, and analyzed by gas chromatography with flame ionization detection. The method was validated from 0.1× to 20× the target level of 0.5 ppm (2.3 mg/m(3)) for a 9.6 L air volume. Desorption efficiencies for HFO-1234yf were 88 to 109% for all replicates over the validation range with a mean overall recovery of 93%. Simulated sampling efficiencies ranged from 87 to 104% with a mean of 94%. No migration or breakthrough to the back tube was observed under the sampling conditions evaluated. HFO-1234yf samples showed acceptable storage stability on Anasorb CSC sorbent up to a period of 30 days when stored under ambient, refrigerated, or frozen temperature conditions.

Danger in the Air: Air Pollution and Cognitive Dysfunction.

PubMed

Cipriani, Gabriele; Danti, Sabrina; Carlesi, Cecilia; Borin, Gemma

2018-01-01

Clean air is considered to be a basic requirement for human health and well-being. To examine the relationship between cognitive performance and ambient pollution exposure. Studies were identified through a systematic search of online scientific databases, in addition to a manual search of the reference lists from the identified papers. Air pollution is a multifaceted toxic chemical mixture capable of assaulting the central nervous system. Despite being a relatively new area of investigation, overall, there is mounting evidence implicating adverse effects of air pollution on cognitive function in both adults and children. Consistent evidence showed that exposure to air pollution, specifically exposure to particulate matter, caused poor age-related cognitive performance. Living in areas with high levels of air pollution has been linked to markers of neuroinflammation and neuropathology that are associated with neurodegenerative conditions such as Alzheimer's disease-like brain pathologies.

1990 Clean Air Act Amendment Summary: Title VI

EPA Pesticide Factsheets

This page provides an overview of the 1990 amendments to Title VI of the Clean Air Act, which were enacted to curb acid rain, urban air pollution and toxic air emissions. The edits to this title deal with stratospheric ozone and global climate protection.

Initial Retrieval Validation from the Joint Airborne IASI Validation Experiment (JAIVEx)

NASA Technical Reports Server (NTRS)

Zhou, Daniel K.; Liu, Xu; Smith, WIlliam L.; Larar, Allen M.; Taylor, Jonathan P.; Revercomb, Henry E.; Mango, Stephen A.; Schluessel, Peter; Calbet, Xavier

2007-01-01

The Joint Airborne IASI Validation Experiment (JAIVEx) was conducted during April 2007 mainly for validation of the Infrared Atmospheric Sounding Interferometer (IASI) on the MetOp satellite, but also included a strong component focusing on validation of the Atmospheric InfraRed Sounder (AIRS) aboard the AQUA satellite. The cross validation of IASI and AIRS is important for the joint use of their data in the global Numerical Weather Prediction process. Initial inter-comparisons of geophysical products have been conducted from different aspects, such as using different measurements from airborne ultraspectral Fourier transform spectrometers (specifically, the NPOESS Airborne Sounder Testbed Interferometer (NAST-I) and the Scanning-High resolution Interferometer Sounder (S-HIS) aboard the NASA WB-57 aircraft), UK Facility for Airborne Atmospheric Measurements (FAAM) BAe146-301 aircraft insitu instruments, dedicated dropsondes, radiosondes, and ground based Raman Lidar. An overview of the JAIVEx retrieval validation plan and some initial results of this field campaign are presented.

Developing an Experimental Model of Vascular Toxicity in Embryonic Zebrafish

EPA Science Inventory

Developing an Experimental Model of Vascular Toxicity in Embryonic Zebrafish Tamara Tal, Integrated Systems Toxicology Division, U.S. EPA Background: There are tens of thousands of chemicals that have yet to be fully evaluated for their toxicity by validated in vivo testing ...

Air-liquid interface exposure to aerosols of poorly soluble nanomaterials induces different biological activation levels compared to exposure to suspensions.

PubMed

Loret, Thomas; Peyret, Emmanuel; Dubreuil, Marielle; Aguerre-Chariol, Olivier; Bressot, Christophe; le Bihan, Olivier; Amodeo, Tanguy; Trouiller, Bénédicte; Braun, Anne; Egles, Christophe; Lacroix, Ghislaine

2016-11-03

exposure of cells at the air-liquid interface represents a valid and sensitive method to assess the toxicity of several poorly soluble nanomaterials. We underlined the importance of the cellular model used and offer the possibility to deal with low deposition doses by using more sensitive and physiologic cellular models. This brings perspectives towards the use of relevant in vitro methods of exposure to assess nanomaterial toxicity.

Field Validation of Toxicity Tests to Evaluate the Potential for Beneficial Use of Produced Water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joseph Bidwell; Jonathan Fisher; Naomi Cooper

2008-03-31

This study investigated potential biological effects of produced water contamination derived from occasional surface overflow and possible subsurface intrusion at an oil production site along the shore of Skiatook Lake, Oklahoma. We monitored basic chemistry and acute toxicity to a suite of standard aquatic test species (fathead minnow-Pimephales promelas, Daphnia pulex, Daphnia magna, and Ceriodaphnia dubia) in produced water and in samples taken from shallow groundwater wells on the site. Toxicity identification evaluations and ion toxicity modeling were used to identify toxic constituents in the samples. Lake sediment at the oil production site and at a reference site were alsomore » analyzed for brine intrusion chemically and by testing sediment toxicity using the benthic invertebrates, Chironomus dilutus, and Hyallela azteca. Sediment quality was also assessed with in situ survival and growth studies with H. azteca and the Asian clam, Corbicula fluminea, and by benthic macroinvertebrate community sampling. The produced water was acutely toxic to the aquatic test organisms at concentrations ranging from 1% to 10% of the whole produced water sample. Toxicity identification evaluation and ion toxicity modeling indicated major ion salts and hydrocarbons were the primary mixture toxicants. The standardized test species used in the laboratory bioassays exhibited differences in sensitivity to these two general classes of contaminants, which underscores the importance of using multiple species when evaluating produced water toxicity. Toxicity of groundwater was greater in samples from wells near a produced water injection well and an evaporation pond. Principle component analyses (PCA) of chemical data derived from the groundwater wells indicated dilution by lake water and possible biogeochemical reactions as factors that ameliorated groundwater toxicity. Elevated concentrations of major ions were found in pore water from lake sediments, but toxicity from these ions

Development of a toxicity identification evaluation procedure for characterizing metal toxicity in marine sediments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burgess, R.M.; Cantwell, M.G.; Pelletier, M.C.

2000-04-01

A multiagency effort is underway to develop whole sediment toxicity identification evaluation (TIE) methods. Whole sediment TIE methods will be critical tools for characterizing toxicity at hazardous waste sites and in the conduct of environmental risk assessments. The research approach is based on the predominance of three classes of toxicants in sediments: ammonia, nonpolar organic chemicals, and metals. Here the authors describe a procedure for characterizing acute toxicity caused by metals in whole marine sediments. The procedure involves adding a chelating resin to sediments, resulting in the sequestration of bioavailable metal while not stressing testing organisms. Within the testing chambers,more » the presence of resin resulted in statistically significant reductions in the overlying and interstitial water concentrations of five metals (cadmium, copper, nickel, lead, and zinc) generally by factors of 40 and 200. Toxicity to both the amphipod Ampelisca abdita and mysid Americamysis bahia (formerly Mysidopsis bahia) of sediments spiked with the five metals was decreased by approximately a factor of four when resin was present. While very effective at reducing the concentrations and toxicity of metals, the resin has only minor ameliorative effects on the toxicity of ammonia and a representative nonpolar toxicant (Endosulfan). Resin and accumulated metal were easily isolated from the testing system following exposures allowing for the initiation of phase II TIE (identification) procedures. This procedure using the addition of a chelating resin provides an approach for determining the importance of metals to the toxicity of marine sediments. Work is continuing to validate the method with environmentally contaminated sediments.« less

40 CFR 80.820 - What gasoline is subject to the toxics performance requirements of this subpart?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 17 2013-07-01 2013-07-01 false What gasoline is subject to the toxics... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Gasoline Toxics Performance Requirements § 80.820 What gasoline is subject to the toxics performance...

40 CFR 80.820 - What gasoline is subject to the toxics performance requirements of this subpart?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 17 2012-07-01 2012-07-01 false What gasoline is subject to the toxics... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Gasoline Toxics Performance Requirements § 80.820 What gasoline is subject to the toxics performance...

40 CFR 80.820 - What gasoline is subject to the toxics performance requirements of this subpart?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 17 2014-07-01 2014-07-01 false What gasoline is subject to the toxics... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Gasoline Toxics Performance Requirements § 80.820 What gasoline is subject to the toxics performance...

Validity of fish, birds and mammals as surrogates for amphibians and reptiles in pesticide toxicity assessment.

PubMed

Ortiz-Santaliestra, Manuel E; Maia, Joao P; Egea-Serrano, Andrés; Lopes, Isabel

2018-02-28

Amphibians and reptiles are the two most endangered groups of vertebrates. Environmental pollution by pesticides is recognised as one of the major factors threatening populations of these groups. However, the effects of pesticides on amphibians and reptiles have been studied for few substances, which is partly related to the fact that these animals are not included in the mandatory toxicity testing conducted as part of environmental risk assessments of pesticides. Whether risks of pesticides to amphibians and reptiles are addressed by surrogate taxa used in risk assessment is currently under debate. In order to develop a scientifically sound and robust risk assessment scheme, information needs to be gathered to examine whether fish, birds and mammals are valid surrogates for amphibians and reptiles. We updated a systematic review of scientific literature that was recently published compiling toxicity data on amphibians and reptiles. The outcome of this review was analysed with the purposes to (1) compare endpoints from amphibians and reptiles with the available information from fish, birds and mammals, and (2) develop species sensitivity distributions (SSDs) for those substances tested in at least six amphibian species (no substances were found tested in at least six reptile species) to identify a candidate amphibian model species to be used as surrogate in risk assessment. A positive correlation was found between toxicity recorded on fish and amphibians, the former revealing, in general, to be more sensitive than the latter to waterborne pollutants. In the terrestrial environment, although birds and mammals were more sensitive than amphibians and reptiles to at least 60% of tested substances, just a few weak significant correlations were observed. As a general rule, homoeothermic vertebrates are not good surrogates for reptiles and terrestrial amphibians in pesticide risk assessment. However, some chemical-dependent trends were detected, with pyrethroids and

Validation of Test Methods for Air Leak Rate Verification of Spaceflight Hardware

NASA Technical Reports Server (NTRS)

Oravec, Heather Ann; Daniels, Christopher C.; Mather, Janice L.

2017-01-01

As deep space exploration continues to be the goal of NASAs human spaceflight program, verification of the performance of spaceflight hardware becomes increasingly critical. Suitable test methods for verifying the leak rate of sealing systems are identified in program qualification testing requirements. One acceptable method for verifying the air leak rate of gas pressure seals is the tracer gas leak detector method. In this method, a tracer gas (commonly helium) leaks past the test seal and is transported to the leak detector where the leak rate is quantified. To predict the air leak rate, a conversion factor of helium-to-air is applied depending on the magnitude of the helium flow rate. The conversion factor is based on either the molecular mass ratio or the ratio of the dynamic viscosities. The current work was aimed at validating this approach for permeation-level leak rates using a series of tests with a silicone elastomer O-ring. An established pressure decay method with constant differential pressure was used to evaluate both the air and helium leak rates of the O-ring under similar temperature and pressure conditions. The results from the pressure decay tests showed, for the elastomer O-ring, that neither the molecular flow nor the viscous flow helium-to-air conversion factors were applicable. Leak rate tests were also performed using nitrogen and argon as the test gas. Molecular mass and viscosity based helium-to-test gas conversion factors were applied, but did not correctly predict the measured leak rates of either gas. To further this study, the effect of pressure boundary conditions was investigated. Often, pressure decay leak rate tests are performed at a differential pressure of 101.3 kPa with atmospheric pressure on the downstream side of the test seal. In space applications, the differential pressure is similar, but with vacuum as the downstream pressure. The same O-ring was tested at four unique differential pressures ranging from 34.5 to 137.9 k

Toxic Release Inventory Chemicals by Groupings

EPA Pesticide Factsheets

The Toxics Release Inventory (TRI) makes available information for more than 600 toxic chemicals that are being used, manufactured, treated, transported, or released into the environment since 1987. EPA makes changes (additions, deletions, or changes in definition) to the TRI chemical list. As a result, the TRI list of reportable toxic chemicals can vary from year to year. EPA created groupings such as the core chemical lists (of 1988, 1991, 1995, 1998, 2000, and 2001) to facilitate year-to-year comparison based on a consistent set of reporting requirements and assure that changes in TRI release or other waste management amounts do not reflect the addition, deletion, or change in definition of reportable chemicals. EPA also created groupings of specific chemicals of interest by categories such as Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), Hazardous Air Pollutants (HAPs), Metals, Newly Added TRI Chemicals in 1995, Occupational Safety and Health Administration (OSHA, Carcinogens), Persistent Bioaccumulative and Toxic (PBT) Chemicals, and Priority Chemicals.

Toxicology of the air in closed spaces

NASA Technical Reports Server (NTRS)

Wands, R. C.

1975-01-01

Sources and identification of contaminants in artificial gas atmospheres are discussed. They include biological sources (microflora and man), materials, processes, aerosols, and malfunctions. Acute or chronic toxicity may result from spacecraft air contamination. Air quality standards are presented in tabular form.

Validation of Interannual Differences of AIRS Monthly Mean Parameters

NASA Technical Reports Server (NTRS)

Susskind, Joel; Iredell, Lena; Keita, Fricky; Molnar, Gyula

2005-01-01

Monthly mean fields of select geophysical parameters derived from analysis of AIRS/AMSU data, and their interannual differences, are shown and compared with analogous fields derived from other sources. All AIRS fields are derived using the AIRS Science Team Version 4 algorithm. Monthly mean results are shown for January 2004, as are interannual differences between January 2004 and January 2003. AIRS temperature and water vapor profile fields are compared with monthly mean collocated ECMWF 3 hour forecast and monthly mean TOVS Pathfinder Path A data. AIRS Tropospheric and Stratospheric coarse climate indicators are compared with analogous MSU products derived by Spencer and christy and found in the TOVS Pathfinder Path A data set. Total ozone is compared with results produced by TOMS. OLR is compared with OLR derived using CERES data and found in the TOVS Pathfinder Path A data set. AIRS results agree well in all cases, especially in the interannual difference sense.

Validation of Atmospheric InfraRed Sounder (AIRS) spectral radiances with the Scanning High-resolution Interferometer Sounder (S-HIS) aircraft instrument

NASA Astrophysics Data System (ADS)

Tobin, David C.; Revercomb, Henry E.; Moeller, Chris C.; Knuteson, Robert O.; Best, Fred A.; Smith, William L.; van Delst, Paul; LaPorte, Daniel D.; Ellington, Scott D.; Werner, Mark D.; Dedecker, Ralph G.; Garcia, Raymond K.; Ciganovich, Nick N.; Howell, Hugh B.; Dutcher, Steven B.; Taylor, Joe K.

2004-11-01

The ability to accurately validate high spectral resolution infrared radiance measurements from space using comparisons with aircraft spectrometer observations has been successfully demonstrated. The demonstration is based on an under-flight of the Atmospheric Infrared Sounder (AIRS) on the NASA Aqua spacecraft by the Scanning High resolution Interferometer Sounder (S-HIS) on the NASA ER-2 high altitude aircraft on 21 November 2002 and resulted in brightness temperature differences approaching 0.1K for most of the spectrum. This paper presents the details of this AIRS/S-HIS validation case and also presents comparisons of Aqua AIRS and Moderate Resolution Imaging Spectroradiometer (MODIS) radiance observations. Aircraft comparisons of this type provide a mechanism for periodically testing the absolute calibration of spacecraft instruments with instrumentation for which the calibration can be carefully maintained on the ground. This capability is especially valuable for assuring the long-term consistency and accuracy of climate observations. It is expected that aircraft flights of the S-HIS and its close cousin the National Polar Orbiting Environmental Satellite System (NPOESS) Atmospheric Sounder Testbed (NAST) will be used to check the long-term stability of the NASA EOS spacecrafts (Terra, Aqua and Aura) and the follow-on complement of operational instruments, including the Cross-track Infrared Sounder (CrIS).

A Different Approach to Validating Screening Assays for Developmental Toxicity

EPA Science Inventory

BACKGROUND: There continues to be many efforts around the world to develop assays that are shorter than the traditional embryofetal developmental toxicity assay, or use fewer or no mammals, or use less compound, or have all three attributes. Each assay developer needs to test th...

Simulation of a tethered microgravity robot pair and validation on a planar air bearing

NASA Astrophysics Data System (ADS)

Mantellato, R.; Lorenzini, E. C.; Sternberg, D.; Roascio, D.; Saenz-Otero, A.; Zachrau, H. J.

2017-09-01

A software model has been developed to simulate the on-orbit dynamics of a dual-mass tethered system where one or both of the tethered spacecraft are able to produce propulsive thrust. The software simulates translations and rotations of both spacecraft, with the visco-elastic tether being simulated as a lumped-mass model. Thanks to this last feature, tether longitudinal and lateral modes of vibration and tether tension can be accurately assessed. Also, the way the spacecraft motion responds to sudden tether tension spikes can be studied in detail. The code enables the simulation of different scenarios, including space tug missions for deorbit maneuvers in a debris mitigation context and general-purpose tethered formation flight missions. This study aims to validate the software through a representative test campaign performed with the MIT Synchronized Position Hold Engage and Reorient Experimental Satellites (SPHERES) planar air bearing system. Results obtained with the numerical simulator are compared with data from direct measurements in different testing setups. The studied cases take into account different initial conditions of the spacecraft velocities and relative attitudes, and thrust forces. Data analysis is presented comparing the results of the simulations with direct measurements of acceleration and Azimuth rate of the two bodies in the planar air bearing test facility using a Nylon tether. Plans for conducting a microgravity test campaign using the SPHERES satellites aboard the International Space Station are also being scheduled in the near future in order to further validate the simulation using data from the relevant operational environment of extended microgravity with full six degree of freedom (per body) motion.

Biomagnetic monitoring as a validation tool for local air quality models: a case study for an urban street canyon.

PubMed

Hofman, Jelle; Samson, Roeland

2014-09-01

Biomagnetic monitoring of tree leaf deposited particles has proven to be a good indicator of the ambient particulate concentration. The objective of this study is to apply this method to validate a local-scale air quality model (ENVI-met), using 96 tree crown sampling locations in a typical urban street canyon. To the best of our knowledge, the application of biomagnetic monitoring for the validation of pollutant dispersion modeling is hereby presented for the first time. Quantitative ENVI-met validation showed significant correlations between modeled and measured results throughout the entire in-leaf period. ENVI-met performed much better at the first half of the street canyon close to the ring road (r=0.58-0.79, RMSE=44-49%), compared to second part (r=0.58-0.64, RMSE=74-102%). The spatial model behavior was evaluated by testing effects of height, azimuthal position, tree position and distance from the main pollution source on the obtained model results and magnetic measurements. Our results demonstrate that biomagnetic monitoring seems to be a valuable method to evaluate the performance of air quality models. Due to the high spatial and temporal resolution of this technique, biomagnetic monitoring can be applied anywhere in the city (where urban green is present) to evaluate model performance at different spatial scales. Copyright © 2014 Elsevier Ltd. All rights reserved.

Calibration and Validation of Aqua AIRS and AMSU Measurements using COSMIC Global Positioning System Radio Occultation Observations

NASA Astrophysics Data System (ADS)

Ho, S. P.; Peng, L.

2015-12-01

On board NASA Aqua satellite, the hyper-spectral infrared sounding from Atmospheric Infrared Sounder (AIRS) is the first of a new generation of operational remote sensors for upwelling atmospheric emission that provide excellent temperature and water vapor retrievals at middle atmosphere, which has significant impacts on short-term numerical weather forecasts. Also on board NASA Aqua satellite, Advanced Microwave Sounding Unit (AMSU) measurements provide the all weather temperature and water vapor profiles which are used as the first guess for AIRS inversion algorithm. However, due to lack of absolute on orbit calibration, both AIRS and AMSU also exhibit biases in retrieving atmospheric temperatures and moistures when compared with in situ measurements. These retrieval biases have diverse and complex dependencies on the temperature/moisture being measured, the season and geographical location, surface conditions, and sensor temperature, which is difficult to quantify. The purpose of this study is to demonstrate the usefulness of Global Positioning System (GPS) Radio Occultation (RO) data to serve as a climate calibration observatory in orbit to calibrate and validate AIRS and AMSU measurements. In this study, we use COSMIC RO data to simulate AMSU and AIRS brightness temperatures for the lower stratosphere (TLS) and compare them to AMSU TLS and those of AIRS brightness temperatures at the same height. Our analysis shows that because RO data do not contain mission-dependent biases and orbit drift errors, and are not affected by on-orbit heating and cooling of the satellite component, they are very useful to identify the AMSU time/location dependent biases for different NOAA missions and possible long term drift of the AIRS retrieved temperatures.

Validation of the portable Air-Smart Spirometer

PubMed Central

Núñez Fernández, Marta; Pallares Sanmartín, Abel; Mouronte Roibas, Cecilia; Cerdeira Domínguez, Luz; Botana Rial, Maria Isabel; Blanco Cid, Nagore; Fernández Villar, Alberto

2018-01-01

Background The Air-Smart Spirometer is the first portable device accepted by the European Community (EC) that performs spirometric measurements by a turbine mechanism and displays the results on a smartphone or a tablet. Methods In this multicenter, descriptive and cross-sectional prospective study carried out in 2 hospital centers, we compare FEV1, FVC, FEV1/FVC ratio measured with the Air Smart-Spirometer device and a conventional spirometer, and analyze the ability of this new portable device to detect obstructions. Patients were included for 2 consecutive months. We calculate sensitivity, specificity, positive and negative predictive value (PPV and NPV) and likelihood ratio (LR +, LR-) as well as the Kappa Index to evaluate the concordance between the two devices for the detection of obstruction. The agreement and relation between the values of FEV1 and FVC in absolute value and the FEV1/FVC ratio measured by both devices were analyzed by calculating the intraclass correlation coefficient (ICC) and the Pearson correlation coefficient (r) respectively. Results 200 patients (100 from each center) were included with a mean age of 57 (± 14) years, 110 were men (55%). Obstruction was detected by conventional spirometry in 73 patients (40.1%). Using a FEV1/FVC ratio smaller than 0.7 to detect obstruction with the Air Smart-Spirometer, the kappa index was 0.88, sensitivity (90.4%), specificity (97.2%), PPV (95.7%), NPV (93.7%), positive likelihood ratio (32.29), and negative likelihood ratio (0.10). The ICC and r between FEV1, FVC, and FEV1 / FVC ratio measured by the Air Smart Spirometer and the conventional spirometer were all higher than 0.94. Conclusion The Air-Smart Spirometer is a simple and very precise instrument for detecting obstructive airway diseases. It is easy to use, which could make it especially useful non-specialized care and in other areas. PMID:29474502

Review of chemical, medication, and anesthesia toxicity in the OR.

PubMed

Fiedler, M A; Biddle, C

1998-02-01

A host of toxic substances exist in the OR. The toxicity of prep solutions, cleaning chemicals, common medications, and trace anesthetic gases varies greatly. Nurses use, direct others in the use of, or administer potential toxins while breathing air that may be contaminated to some degree with anesthetic vapors. Often, the OR nurse is the neighborhood resource when questions about the toxicity of common chemicals and drugs arise. A general knowledge of the toxicity of these substances improves the nurse's ability to assess the risk from trace anesthetic gases, prevent injury to patients, provide first aid when potentially dangerous exposure occurs, and direct others in the safe use of OR chemicals.

Equivalent air depth: fact or fiction.

PubMed

Berghage, T E; McCraken, T M

1979-12-01

In mixed-gas diving theory, the equivalent air depth (EAD) concept suggests that oxygen does not contribute to the total tissue gas tension and can therefore be disregarded in calculations of the decompression process. The validity of this assumption has been experimentally tested by exposing 365 rats to various partial pressures of oxygen for various lengths of time. If the EAD assumption is correct, under a constant exposure pressure each incremental change in the oxygen partial pressure would produce a corresponding incremental change in pressure reduction tolerance. Results of this study suggest that the EAD concept does not adequately describe the decompression advantages obtained from breathing elevated oxygen partial pressures. The authors suggest that the effects of breathing oxygen vary in a nonlinear fashion across the range from anoxia to oxygen toxicity, and that a simple inert gas replacement concept is no longer tenable.

Performance Assessment of Hazardous Air Pollutant (HAP)Free Chemical Paint Strippers on Military Coatings for Validation to Federal Specification TT-R-2918A

DTIC Science & Technology

2016-03-01

ARL-TN-0742 ● MAR 2016 US Army Research Laboratory Performance Assessment of Hazardous Air Pollutant (HAP)–Free Chemical Paint ...Free Chemical Paint Strippers on Military Coatings for Validation to Federal Specification TT-R-2918A by Lindsey Blohm Oak Ridge Institute for...COVERED (From - To) 1–30 April 2014 4. TITLE AND SUBTITLE Performance Assessment of Hazardous Air Pollutant (HAP)–Free Chemical Paint Strippers

Use of the Cultex® Radial Flow System as an in vitro exposure method to assess acute pulmonary toxicity of fine dusts and nanoparticles with special focus on the intra- and inter-laboratory reproducibility.

PubMed

Steinritz, Dirk; Möhle, Niklas; Pohl, Christine; Papritz, Mirko; Stenger, Bernhard; Schmidt, Annette; Kirkpatrick, Charles James; Thiermann, Horst; Vogel, Richard; Hoffmann, Sebastian; Aufderheide, Michaela

2013-12-05

Exposure of the respiratory tract to airborne particles (including metal-dusts and nano-particles) is considered as a serious health hazard. For a wide range of substances basic knowledge about the toxic properties and the underlying pathomechanisms is lacking or even completely missing. Legislation demands the toxicological characterization of all chemicals placed on the market until 2018 (REACH). As toxicological in vivo data are rare with regard to acute lung toxicity or exhibit distinct limitations (e.g. inter-species differences) and legislation claims the reduction of animal experiments in general ("3R" principle), profound in vitro models have to be established and characterized to meet these requirements. In this paper we characterize a recently introduced advanced in vitro exposure system (Cultex® RFS) showing a great similarity to the physiological in vivo exposure situation for the assessment of acute pulmonary toxicity of airborne materials. Using the Cultex® RFS, human lung epithelial cells (A549 cells) were exposed to different concentrations of airborne metal dusts (nano- and microscale particles) at the air-liquid-interface (ALI). Cell viability (WST-1 assay) as a parameter of toxicity was assessed 24h after exposure with special focus on the intra- and inter-laboratory (three independent laboratories) reproducibility. Our results show the general applicability of the Cultex® RFS with regard to the requirements of the ECVAM (European Centre for the Validation of Alternative Methods) principles on test validity underlining its robustness and stability. Intra- and inter-laboratory reproducibility can be considered as sufficient if predefined quality criteria are respected. Special attention must be paid to the pure air controls that turned out to be a critical parameter for a rational interpretation of the results. Our results are encouraging and future work is planned to improve the inter-laboratory reproducibility, to consolidate the results so

Comparative toxicity of two azadirachtin-based neem pesticides to Daphnia pulex.

PubMed

Goktepe, Ipek; Plhak, Leslie C

2002-01-01

Azadirachtin (AZA)-based pesticides (Neemix and Bioneem) demonstrated toxicity in 48-h nonrenewal toxicity assays using Daphnia pulex at levels that were comparable with several organophosphate pesticides. The median lethal concentration (LC50) values for the two neem pesticides were found to be 0.028 and 0.033 microl/ml, respectively. The LC50 value for nonformulated (95% pure) AZA was determined to be 0.382 microg AZA/ml. Neemix and Bioneem were exposed to air and northern sky daylight in a light box at 24 and 37 degrees C for 1, 3, 6, and 9 d. Standard 48-h acute toxicity tests were used to determine the effect of aging in these dry environmental conditions. Neemix and Bioneem were also fractionated into volatile and nonvolatile fractions, and the toxicity of each was tested. Compared with Neemix, Bioneem remained toxic longer when exposed to light and air at 37 degrees C, indicating that this pesticide may be less prone to environmental degradation. When fractionated, the nonvolatile fractions for both pesticides exhibited significantly lower LC50 values than the full formulations. These results suggest that, depending on the application rate and environmental fate, AZA-based pesticides may have direct adverse effects on aquatic organisms and that the toxicity and stability of formulated pesticides depend on factors other than only the AZA concentration.

40 CFR Table 3 to Subpart X of... - Toxic Equivalency Factors

Code of Federal Regulations, 2014 CFR

2014-07-01

... Subpart X of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Standards For Hazardous Air Pollutants From Secondary Lead Smelting Pt. 63, Subpt. X, Table 3 Table 3 to Subpart X of Part 63—Toxic Equivalency Factors Dioxin/furan congener Toxicequivalency factor 2,3,7,8...

REDUCING UNCERTAINTY IN AIR TOXICS RISK ASSESSMENT: A MECHANISTIC EXPOSURE-DOSE-RESPONSE (EDR) MODEL FOR ASSESSING THE ACUTE NEUROTOXICITY OF VOLATILE ORGANIC COMPOUNDS (VOCS) BASED UPON A RECEPTOR-MEDIATED MODE OF ACTION

EPA Science Inventory

SUMMARY: The major accomplishment of NTD’s air toxics program is the development of an exposure-dose- response model for acute exposure to volatile organic compounds (VOCs), based on momentary brain concentration as the dose metric associated with acute neurological impairments...

1990 Clean Air Act Amendment Summary: Title V

EPA Pesticide Factsheets

In 1989, President George W. Bush proposed legislation designed to curb three major threats to the environment and public health: acid rain, urban air pollution, and toxic air emissions. The proposal also called for establishing a national permits program.

Quantification of variability and uncertainty for air toxic emission inventories with censored emission factor data.

PubMed

Frey, H Christopher; Zhao, Yuchao

2004-11-15

Probabilistic emission inventories were developed for urban air toxic emissions of benzene, formaldehyde, chromium, and arsenic for the example of Houston. Variability and uncertainty in emission factors were quantified for 71-97% of total emissions, depending upon the pollutant and data availability. Parametric distributions for interunit variability were fit using maximum likelihood estimation (MLE), and uncertainty in mean emission factors was estimated using parametric bootstrap simulation. For data sets containing one or more nondetected values, empirical bootstrap simulation was used to randomly sample detection limits for nondetected values and observations for sample values, and parametric distributions for variability were fit using MLE estimators for censored data. The goodness-of-fit for censored data was evaluated by comparison of cumulative distributions of bootstrap confidence intervals and empirical data. The emission inventory 95% uncertainty ranges are as small as -25% to +42% for chromium to as large as -75% to +224% for arsenic with correlated surrogates. Uncertainty was dominated by only a few source categories. Recommendations are made for future improvements to the analysis.

Global concentration additivity and prediction of mixture toxicities, taking nitrobenzene derivatives as an example.

PubMed

Li, Tong; Liu, Shu-Shen; Qu, Rui; Liu, Hai-Ling

2017-10-01

The toxicity of a mixture depends not only on the mixture concentration level but also on the mixture ratio. For a multiple-component mixture (MCM) system with a definite chemical composition, the mixture toxicity can be predicted only if the global concentration additivity (GCA) is validated. The so-called GCA means that the toxicity of any mixture in the MCM system is the concentration additive, regardless of what its mixture ratio and concentration level. However, many mixture toxicity reports have usually employed one mixture ratio (such as the EC 50 ratio), the equivalent effect concentration ratio (EECR) design, to specify several mixtures. EECR mixtures cannot simulate the concentration diversity and mixture ratio diversity of mixtures in the real environment, and it is impossible to validate the GCA. Therefore, in this paper, the uniform design ray (UD-Ray) was used to select nine mixture ratios (rays) in the mixture system of five nitrobenzene derivatives (NBDs). The representative UD-Ray mixtures can effectively and rationally describe the diversity in the NBD mixture system. The toxicities of the mixtures to Vibrio qinghaiensis sp.-Q67 were determined by the microplate toxicity analysis (MTA). For each UD-Ray mixture, the concentration addition (CA) model was used to validate whether the mixture toxicity is additive. All of the UD-Ray mixtures of five NBDs are global concentration additive. Afterwards, the CA is employed to predict the toxicities of the external mixtures from three EECR mixture rays with the NOEC, EC 30 , and EC 70 ratios. The predictive toxicities are in good agreement with the experimental toxicities, which testifies to the predictability of the mixture toxicity of the NBDs. Copyright © 2017. Published by Elsevier Inc.

Development, validity and reliability of a new pressure air biofeedback device (PAB) for measuring isometric extension strength of the lumbar spine.

PubMed

Pienaar, Andries W; Barnard, Justhinus G

2017-04-01

This study describes the development of a new portable muscle testing device, using air pressure as a biofeedback and strength testing tool. For this purpose, a pressure air biofeedback device (PAB ® ) was developed to measure and record the isometric extension strength of the lumbar multifidus muscle in asymptomatic and low back pain (LBP) persons. A total of 42 subjects (age 47.58 years, ±18.58) participated in this study. The validity of PAB ® was assessed by comparing a selected measure, air pressure force in millibar (mb), to a standard criterion; calibrated weights in kilograms (kg) during day-to-day tests. Furthermore, clinical trial-to-trial and day-to-day tests of maximum voluntary isometric contraction (MVIC) of L5 lumbar multifidus were done to compare air pressure force (mb) to electromyography (EMG) in microvolt (μV) and to measure the reliability of PAB ® . A highly significant relationship were found between air pressure output (mb) and calibrated weights (kg). In addition, Pearson correlation calculations showed a significant relationship between PAB ® force (mb) and EMG activity (μV) for all subjects (n = 42) examined, as well as for the asymptomatic group (n = 24). No relationship was detected for the LBP group (n = 18). In terms of lumbar extension strength, we found that asymptomatic subjects were significantly stronger than LBP subjects. The results of the PAB ® test differentiated between LBP and asymptomatic subject's lumbar isometric extension strength without any risk to the subjects and also indicate that the lumbar isometric extension test with the new PAB ® device is reliable and valid.

Development and validation of an OECD reproductive toxicity test guideline with the pond snail Lymnaea stagnalis (Mollusca, Gastropoda).

PubMed

Ducrot, Virginie; Askem, Clare; Azam, Didier; Brettschneider, Denise; Brown, Rebecca; Charles, Sandrine; Coke, Maïra; Collinet, Marc; Delignette-Muller, Marie-Laure; Forfait-Dubuc, Carole; Holbech, Henrik; Hutchinson, Thomas; Jach, Arne; Kinnberg, Karin L; Lacoste, Cédric; Le Page, Gareth; Matthiessen, Peter; Oehlmann, Jörg; Rice, Lynsey; Roberts, Edward; Ruppert, Katharina; Davis, Jessica Elphinstone; Veauvy, Clemence; Weltje, Lennart; Wortham, Ruth; Lagadic, Laurent

2014-12-01

The OECD test guideline development program has been extended in 2011 to establish a partial life-cycle protocol for assessing the reproductive toxicity of chemicals to several mollusk species, including the great pond snail Lymnaea stagnalis. In this paper, we summarize the standard draft protocol for a reproduction test with this species, and present inter-comparison results obtained in a 56-day prevalidation ring-test using this protocol. Seven European laboratories performed semi-static tests with cultured snails of the strain Renilys® exposed to nominal concentrations of cadmium chloride (from 53 to 608μgCdL(-1)). Cd concentrations in test solutions were analytically determined to confirm accuracy in the metal exposure concentrations in all laboratories. Physico-chemical and biological validity criteria (namely dissolved oxygen content >60% ASV, water temperature 20±1°C, control snail survival >80% and control snail fecundity >8 egg-masses per snail over the test period) were met in all laboratories which consistently demonstrated the reproductive toxicity of Cd in snails using the proposed draft protocol. Effect concentrations for fecundity after 56days were reproducible between laboratories (68validation ring-test involving 14 laboratories in Europe, North- and South-America is currently being implemented using four chemicals (Cd, prochloraz, trenbolone

Use of electrochemical sensors for measurement of air pollution: correcting interference response and validating measurements

NASA Astrophysics Data System (ADS)

Cross, Eben S.; Williams, Leah R.; Lewis, David K.; Magoon, Gregory R.; Onasch, Timothy B.; Kaminsky, Michael L.; Worsnop, Douglas R.; Jayne, John T.

2017-09-01

The environments in which we live, work, and play are subject to enormous variability in air pollutant concentrations. To adequately characterize air quality (AQ), measurements must be fast (real time), scalable, and reliable (with known accuracy, precision, and stability over time). Lower-cost air-quality-sensor technologies offer new opportunities for fast and distributed measurements, but a persistent characterization gap remains when it comes to evaluating sensor performance under realistic environmental sampling conditions. This limits our ability to inform the public about pollution sources and inspire policy makers to address environmental justice issues related to air quality. In this paper, initial results obtained with a recently developed lower-cost air-quality-sensor system are reported. In this project, data were acquired with the ARISense integrated sensor package over a 4.5-month time interval during which the sensor system was co-located with a state-operated (Massachusetts, USA) air quality monitoring station equipped with reference instrumentation measuring the same pollutant species. This paper focuses on validating electrochemical (EC) sensor measurements of CO, NO, NO2, and O3 at an urban neighborhood site with pollutant concentration ranges (parts per billion by volume, ppb; 5 min averages, ±1σ): [CO] = 231 ± 116 ppb (spanning 84-1706 ppb), [NO] = 6.1 ± 11.5 ppb (spanning 0-209 ppb), [NO2] = 11.7 ± 8.3 ppb (spanning 0-71 ppb), and [O3] = 23.2 ± 12.5 ppb (spanning 0-99 ppb). Through the use of high-dimensional model representation (HDMR), we show that interference effects derived from the variable ambient gas concentration mix and changing environmental conditions over three seasons (sensor flow-cell temperature = 23.4 ± 8.5 °C, spanning 4.1 to 45.2 °C; and relative humidity = 50.1 ± 15.3 %, spanning 9.8-79.9 %) can be effectively modeled for the Alphasense CO-B4, NO-B4, NO2-B43F, and Ox-B421 sensors, yielding (5 min average) root

Toxic chemical release weighted ranking

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petrocchi, A.J.

1989-07-19

The weighted ranking as used in this report is an attempt to combine total air release with recognized exposure limit for each toxic chemical to arrive at a single ranking factor called Release Exposure Index (REI) which takes both release amount and degree of hazard into consideration. The REIs can then be used in decision making to prioritize how these chemicals are addressed. 2 tabs.

Theoretical and experimental validation study on automotive air-conditioning based on heat pipe and LNG cold energy for LNG-fueled heavy vehicles

NASA Astrophysics Data System (ADS)

Deng, Dong; Cheng, Jiang-ping; Zhang, Sheng-chang; Ge, Fang-gen

2017-08-01

As a clean fuel, LNG has been used in heavy vehicles widely in China. Before reaching the engine for combustion, LNG store in a high vacuum multi-layer thermal insulation tank and need to be evaporated from its cryogenic state to natural gas. During the evaporation, the available cold energy of LNG has been calculated. The concept has been proposed that the separated type heat pipe technology is employed to utilize the available cold energy for automotive air-conditioning. The experiment has been conducted to validate the proposal. It is found that it is feasible to use the separated type heat pipe to convey the cold energy from LNG to automotive air-conditioning. And the cooling capacity of the automotive air-conditioning increase with the LNG consumption and air flow rate increasing.

Optical remote measurement of toxic gases

NASA Technical Reports Server (NTRS)

Grant, W. B.; Kagann, R. H.; McClenny, W. A.

1992-01-01

Enactment of the Clean Air Act Amendments (CAAA) of 1990 has resulted in increased ambient air monitoring needs for industry, some of which may be met efficiently using open-path optical remote sensing techniques. These techniques include Fourier transform spectroscopy, differential optical absorption spectroscopy, laser long-path absorption, differential absorption lidar, and gas cell correlation spectroscopy. With this regulatory impetus, it is an opportune time to consider applying these technologies to the remote and/or path-averaged measurement and monitoring of toxic gases covered by the CAAA. This article reviews the optical remote sensing technology and literature for that application.

A Cloud Mask for AIRS

NASA Technical Reports Server (NTRS)

Brubaker, N.; Jedlovec, G. J.

2004-01-01

With the preliminary release of AIRS Level 1 and 2 data to the scientific community, there is a growing need for an accurate AIRS cloud mask for data assimilation studies and in producing products derived from cloud free radiances. Current cloud information provided with the AIRS data are limited or based on simplified threshold tests. A multispectral cloud detection approach has been developed for AIRS that utilizes the hyper-spectral capabilities to detect clouds based on specific cloud signatures across the short wave and long wave infrared window regions. This new AIRS cloud mask has been validated against the existing AIRS Level 2 cloud product and cloud information derived from MODIS. Preliminary results for both day and night applications over the continental U.S. are encouraging. Details of the cloud detection approach and validation results will be presented at the conference.

Cross-validation of the osmotic pressure based on Pitzer model with air humidity osmometry at high concentration of ammonium sulfate solutions.

PubMed

Wang, Xiao-Lan; Zhan, Ting-Ting; Zhan, Xian-Cheng; Tan, Xiao-Ying; Qu, Xiao-You; Wang, Xin-Yue; Li, Cheng-Rong

2014-01-01

The osmotic pressure of ammonium sulfate solutions has been measured by the well-established freezing point osmometry in dilute solutions and we recently reported air humidity osmometry in a much wider range of concentration. Air humidity osmometry cross-validated the theoretical calculations of osmotic pressure based on the Pitzer model at high concentrations by two one-sided test (TOST) of equivalence with multiple testing corrections, where no other experimental method could serve as a reference for comparison. Although more strict equivalence criteria were established between the measurements of freezing point osmometry and the calculations based on the Pitzer model at low concentration, air humidity osmometry is the only currently available osmometry applicable to high concentration, serves as an economic addition to standard osmometry.

Past, Present and Emerging Toxicity Issues for Jet Fuel

DTIC Science & Technology

2011-01-01

Statistically significant dominant lethal effects were not observed for either mice or rats (Air Force, 1978). However, because of the small sample...Adams, M.M., 2004. Immunological and hematological effects observed in B6C3F1 mice exposed to JP-8 jet fuel for 14 days. J. Toxicol. Environ. Health A...acute toxicity with the adverse effects being slight dermal irritation and weak dermal sensitization in animals. JP-4 also has low acute toxicity with

APPLICATION OF JET REMPI AND LIBS TO AIR TOXIC MONITORING

EPA Science Inventory

The paper discusses three advanced, laser-based monitoring techniques that the EPA is assisting in developing for real time measurement of toxic aerosol compounds. One of the three techniques is jet resonance enhanced multiphoton ionization (Jet REMPI) coupled with a time-of-flig...

Toxic exposure in America: estimating fetal and infant health outcomes from 14 years of TRI reporting.

PubMed

Agarwal, Nikhil; Banternghansa, Chanont; Bui, Linda T M

2010-07-01

We examine the effect of exposure to a set of toxic pollutants that are tracked by the Toxic Release Inventory (TRI) from manufacturing facilities on county-level infant and fetal mortality rates in the United States between 1989 and 2002. Unlike previous studies, we control for toxic pollution from both mobile sources and non-TRI reporting facilities. We find significant adverse effects of toxic air pollution concentrations on infant mortality rates. Within toxic air pollutants we find that releases of carcinogens are particularly problematic for infant health outcomes. We estimate that the average county-level decreases in various categories of TRI concentrations saved in excess of 13,800 infant lives from 1989 to 2002. Using the low end of the range for the value of a statistical life that is typically used by the EPA of $1.8M, the savings in lives would be valued at approximately $25B.

Food for Thought ... Mechanistic Validation

PubMed Central

Hartung, Thomas; Hoffmann, Sebastian; Stephens, Martin

2013-01-01

Summary Validation of new approaches in regulatory toxicology is commonly defined as the independent assessment of the reproducibility and relevance (the scientific basis and predictive capacity) of a test for a particular purpose. In large ring trials, the emphasis to date has been mainly on reproducibility and predictive capacity (comparison to the traditional test) with less attention given to the scientific or mechanistic basis. Assessing predictive capacity is difficult for novel approaches (which are based on mechanism), such as pathways of toxicity or the complex networks within the organism (systems toxicology). This is highly relevant for implementing Toxicology for the 21st Century, either by high-throughput testing in the ToxCast/ Tox21 project or omics-based testing in the Human Toxome Project. This article explores the mostly neglected assessment of a test's scientific basis, which moves mechanism and causality to the foreground when validating/qualifying tests. Such mechanistic validation faces the problem of establishing causality in complex systems. However, pragmatic adaptations of the Bradford Hill criteria, as well as bioinformatic tools, are emerging. As critical infrastructures of the organism are perturbed by a toxic mechanism we argue that by focusing on the target of toxicity and its vulnerability, in addition to the way it is perturbed, we can anchor the identification of the mechanism and its verification. PMID:23665802

Quantitative structure-activity relationship modeling of rat acute toxicity by oral exposure.

PubMed

Zhu, Hao; Martin, Todd M; Ye, Lin; Sedykh, Alexander; Young, Douglas M; Tropsha, Alexander

2009-12-01

Few quantitative structure-activity relationship (QSAR) studies have successfully modeled large, diverse rodent toxicity end points. In this study, a comprehensive data set of 7385 compounds with their most conservative lethal dose (LD(50)) values has been compiled. A combinatorial QSAR approach has been employed to develop robust and predictive models of acute toxicity in rats caused by oral exposure to chemicals. To enable fair comparison between the predictive power of models generated in this study versus a commercial toxicity predictor, TOPKAT (Toxicity Prediction by Komputer Assisted Technology), a modeling subset of the entire data set was selected that included all 3472 compounds used in TOPKAT's training set. The remaining 3913 compounds, which were not present in the TOPKAT training set, were used as the external validation set. QSAR models of five different types were developed for the modeling set. The prediction accuracy for the external validation set was estimated by determination coefficient R(2) of linear regression between actual and predicted LD(50) values. The use of the applicability domain threshold implemented in most models generally improved the external prediction accuracy but expectedly led to the decrease in chemical space coverage; depending on the applicability domain threshold, R(2) ranged from 0.24 to 0.70. Ultimately, several consensus models were developed by averaging the predicted LD(50) for every compound using all five models. The consensus models afforded higher prediction accuracy for the external validation data set with the higher coverage as compared to individual constituent models. The validated consensus LD(50) models developed in this study can be used as reliable computational predictors of in vivo acute toxicity.

Field validation of sound mitigation models and air pollutant emission testing in support of missile motor disposal activities.

PubMed

McFarland, Michael J; Palmer, Glenn R; Kordich, Micheal M; Pollet, Dean A; Jensen, James A; Lindsay, Mitchell H

2005-08-01

The U.S. Department of Defense approved activities conducted at the Utah Test and Training Range (UTTR) include both operational readiness test firing of intercontinental ballistic missile motors as well as the destruction of obsolete or otherwise unusable intercontinental ballistic missile motors through open burn/open detonation (OB/ OD). Within the Utah Division of Air Quality, these activities have been identified as having the potential to generate unacceptable noise levels, as well as significant amounts of hazardous air pollutants. Hill Air Force Base, UT, has completed a series of field tests at the UTTR in which sound-monitoring surveillance of OB/OD activities was conducted to validate the Sound Intensity Prediction System (SIPS) model. Using results generated by the SIPS model to support the decision to detonate, the UTTR successfully disposed of missile motors having an aggregate net explosive weight (NEW) of 56,500 lbs without generating adverse noise levels within populated areas. These results suggest that, under appropriate conditions, missile motors of even larger NEW may be detonated without exceeding regulatory noise limits. In conjunction with collecting noise monitoring data, air quality data was collected to support the development of air emission factors for both static missile motor firings and OB/OD activities. Through the installation of 15 ground-based air samplers, the generation of combustion fixed gases, hazardous air pollutants, and chlorides were monitored during the 56,500-lb NEW detonation event. Comparison of field measurements to predictions generated from the U.S. Navy's energetic combustion pollutant formation model, POLU4WN, indicated that, as the detonation fireball expanded from ground zero, organic compounds as well as carbon monoxide continued to oxidize as the hot gases reacted with ambient air. Hazardous air pollutant analysis of air samplers confirmed the presence of chloromethane, benzene, toluene, 1,2-propadiene, and

MEASUREMENT OF TOXIC AND RELATED AIR POLLUTANTS - 1993

EPA Science Inventory

A joint conference cosponsored for the eighth year by the Atmospheric Research and Exposure Assessment Laboratory (AREAL) of the U.S. Environmental Protection Agency and the Air & Waste Management Association was held in Durham, North Carolina, May 3-7, 1993. he four day technica...

Toxicity of airborne dust as an indicator of moisture problems in school buildings.

PubMed

Tirkkonen, Jenni; Täubel, Martin; Leppänen, Hanna; Peltonen, Matti; Lindsley, William; Chen, Bean T; Hyvärinen, Anne; Hirvonen, Maija-Riitta; Huttunen, Kati

2017-02-01

Moisture-damaged indoor environments are thought to increase the toxicity of indoor air particulate matter (PM), indicating that a toxicological assay could be used as a method for recognizing buildings with indoor air problems. We aimed to test if our approach of analyzing the toxicity of actively collected indoor air PM in vitro differentiates moisture-damaged from non-damaged school buildings. We collected active air samples with NIOSH Bioaerosol Cyclone Samplers from moisture-damaged (index) and non-damaged (reference) school buildings (4 + 4). The teachers and pupils of the schools were administered a symptom questionnaire. Five samples of two size fractions [Stage 1 (>1.9 μm) and Stage 2 (1-1.9 μm)] were collected from each school. Mouse RAW264.7 macrophages were exposed to the collected PM for 24 h and subsequently analyzed for changes in cell metabolic activity, production of nitric oxide (NO), tumor necrosis factor (TNF)-α and interleukin (IL)-6. The teachers working in the moisture-damaged schools reported respiratory symptoms such as cough (p = 0.01) and shortness of breath (p = 0.01) more often than teachers from reference schools. Toxicity of the PM sample as such did not differentiate index from reference building,s but the toxicity adjusted for the amount of the particles tended to be higher in moisture-damaged schools. Further development of the method will require identification of other confounding factors in addition to the necessity to adjust for differences in particle counts between samples.

Development of Monitors for Assessing Exposure of Military Personnel to Toxic Chemicals.

DTIC Science & Technology

2000-01-01

Residues " S ampler Preparation 7 Transfer and Analysis 7 Temperature Effects on PIMS Sampling Rate 8 Environmental Air Sampling 8 Results and...of exposure and potential toxicity to personnel. While progress has been made in improving active water and air sampling technology, such devices...streams, 3) the apparatus is also applicable for use in air sampling deployments in indoor and outdoor scenarios, and 4) the apparatus is commercially

In silico toxicity prediction by support vector machine and SMILES representation-based string kernel.

PubMed

Cao, D-S; Zhao, J-C; Yang, Y-N; Zhao, C-X; Yan, J; Liu, S; Hu, Q-N; Xu, Q-S; Liang, Y-Z

2012-01-01

There is a great need to assess the harmful effects or toxicities of chemicals to which man is exposed. In the present paper, the simplified molecular input line entry specification (SMILES) representation-based string kernel, together with the state-of-the-art support vector machine (SVM) algorithm, were used to classify the toxicity of chemicals from the US Environmental Protection Agency Distributed Structure-Searchable Toxicity (DSSTox) database network. In this method, the molecular structure can be directly encoded by a series of SMILES substrings that represent the presence of some chemical elements and different kinds of chemical bonds (double, triple and stereochemistry) in the molecules. Thus, SMILES string kernel can accurately and directly measure the similarities of molecules by a series of local information hidden in the molecules. Two model validation approaches, five-fold cross-validation and independent validation set, were used for assessing the predictive capability of our developed models. The results obtained indicate that SVM based on the SMILES string kernel can be regarded as a very promising and alternative modelling approach for potential toxicity prediction of chemicals.

CATSI EDM: recent advances in the development and validation of a ruggedized passive standoff CWA sensor

NASA Astrophysics Data System (ADS)

Lavoie, Hugo; Thériault, Jean-Marc; Bouffard, François; Puckrin, Eldon; Turcotte, Caroline S.; Lacasse, Paul

2008-04-01

Defence Research and Development Canada (DRDC) - Valcartier is currently developing a ruggedized passive standoff sensor for the detection of chemical warfare agents (CWAs) based on differential Fourier-transform infrared (FTIR) radiometry. This system is referred to as the Compact ATmospheric Sounding Interferometer (CATSI) Engineering Development Model (EDM). The CATSI EDM sensor is based on the use of a double-beam FTIR spectrometer that is optimized for optical subtraction. A description of the customized sensor is given along with a discussion on the detection and identification approaches that have been developed. Preliminary results of validation from a number of laboratory measurements and open-air trials are analyzed to establish the capability of detection and identification of various toxic and non-toxic chemical vapor plumes. These results clearly demonstrate the capability of the passive differential radiometric approach for the standoff detection and identification of chemical vapors at distances up to a few kilometers from the sensor.

Acute Toxicity of a Number of Chemicals of Interest to the Air Force

DTIC Science & Technology

1979-03-01

Acid Azelaic Acid Dimer Acid N-Benzyl-3, 7-Dioctyl Phenothiazine Phenothiazine Dioctyl Phenothiazine Sebacic Acid ...liquid) 1,4-dihydroxyanthraquinone (solid) Sulfurized 9-octadecenoic acid (liquid) Azelaic acid (solid) Dimer acid (liquid) N-benzyl-3,7-dicotyl...dihydroxyanthra- Rat >5000 5000(0) Below Toxic quinone Sulfurized 9-octa- Rat >5000 5000(0) Below Toxic decenoic acid Azelaic acid Rat >5000

SIMULATION MODELS FOR ENVIRONMENTAL MULTIMEDIA ANALYSIS OF TOXIC CHEMICALS

EPA Science Inventory

Multimedia understanding of pollutant behavior in the environment is of particular concern for chemicals that are toxic and are subject to accumulation in the environmental media (air, soil, water, vegetation) where biota and human exposure is significant. Multimedia simulation ...

Development and validation of an OECD reproductive toxicity test guideline with the mudsnail Potamopyrgus antipodarum (Mollusca, Gastropoda).

PubMed

Ruppert, Katharina; Geiß, Cornelia; Askem, Clare; Benstead, Rachel; Brown, Rebecca; Coke, Maira; Ducrot, Virginie; Egeler, Philipp; Holbech, Henrik; Hutchinson, Thomas H; Kinnberg, Karin L; Lagadic, Laurent; Le Page, Gareth; Macken, Ailbhe; Matthiessen, Peter; Ostermann, Sina; Schimera, Agnes; Schmitt, Claudia; Seeland-Fremer, Anne; Smith, Andy J; Weltje, Lennart; Oehlmann, Jörg

2017-08-01

Mollusks are known to be uniquely sensitive to a number of reproductive toxicants including some vertebrate endocrine disrupting chemicals. However, they have widely been ignored in environmental risk assessment procedures for chemicals. This study describes the validation of the Potamopyrgus antipodarum reproduction test within the OECD Conceptual Framework for Endocrine Disrupters Testing and Assessment. The number of embryos in the brood pouch and adult mortality serve as main endpoints. The experiments are conducted as static systems in beakers filled with artificial medium, which is aerated trough glass pipettes. The test chemical is dispersed into the medium, and adult snails are subsequently introduced into the beakers. After 28 days the reproductive success is determined by opening the brood pouch and embryo counting. This study presents the results of two validation studies of the reproduction test with eleven laboratories and the chemicals tributyltin (TBT) with nominal concentrations ranging from 10 to 1000 ng TBT-Sn/L and cadmium with concentrations from 1.56 to 25 μg/L. The test design could be implemented by all laboratories resulting in comparable effect concentrations for the endpoint number of embryos in the brood pouch. After TBT exposure mean EC 10 , EC 50 , NOEC and LOEC were 35.6, 127, 39.2 and 75.7 ng Sn/L, respectively. Mean effect concentrations in cadmium exposed snails were, respectively, 6.53, 14.2, 6.45 and 12.6 μg/L. The effect concentrations are in good accordance with already published data. Both validation studies show that the reproduction test with P. antipodarum is a well-suited tool to assess reproductive effects of chemicals. Copyright © 2017 Elsevier Ltd. All rights reserved.

New Jersey: Clean Air Communities (A Former EPA CARE Project)

EPA Pesticide Factsheets

Clean Air Communities (CAC) is the recipient of a Level II CARE cooperative agreement to implement recommendations by the state’s Environmental Justice Task Force and the Air Toxics Pilot Project to reduce environmental risks.

A statistical model for characterizing common air pollutants in air-conditioned offices

NASA Astrophysics Data System (ADS)

Wong, L. T.; Mui, K. W.; Hui, P. S.

Maintaining acceptable indoor air quality (IAQ) for a healthy environment is of primary concern, policymakers have developed different strategies to address the performance of it based on proper assessment methodologies and monitoring plans. It could be cost prohibitive to sample all toxic pollutants in a building. In search of a more manageable number of parameters for cost-effective IAQ assessment, this study investigated the probable correlations among the 12 indoor environmental parameters listed in the IAQ certification scheme of the Hong Kong Environment Protection Department (HKEPD) in 422 Hong Kong offices. These 12 parameters consists of nine indoor air pollutants: carbon dioxide (CO 2), carbon monoxide (CO), respirable suspended particulates (RSP), nitrogen dioxide (NO 2), ozone (O 3), formaldehyde (HCHO), total volatile organic compounds (TVOC), radon (Rn), airborne bacteria count (ABC); and three thermal comfort parameters: temperature ( T), relative humidity (RH) and air velocity ( V). The relative importance of the correlations derived, from largest to smallest loadings, was ABC, Rn, CO, RH, RSP, CO 2, TVOC, O 3, T, V, NO 2 and HCHO. Together with the mathematical expressions derived, an alternative sampling protocol for IAQ assessment with the three 'most representative and independent' parameters namely RSP, CO 2 and TVOC measured in an office environment was proposed. The model validity was verified with on site measurements from 43 other offices in Hong Kong. The measured CO 2, RSP and TVOC concentrations were used to predict the probable levels of the other nine parameters and good agreement was found between the predictions and measurements. This simplified protocol provides an easy tool for performing IAQ monitoring in workplaces and will be useful for determining appropriate mitigation measures to finally honor the certification scheme in a cost-effective way.

Infrequent air contamination with Acinetobacter baumannii of air surrounding known colonized or infected patients.

PubMed

Rock, Clare; Harris, Anthony D; Johnson, J Kristie; Bischoff, Werner E; Thom, Kerri A

2015-07-01

Using a validated air sampling method we found Acinetobacter baumannii in the air surrounding only 1 of 12 patients known to be colonized or infected with A. baumannii. Patients' closed-circuit ventilator status, frequent air exchanges in patient rooms, and short sampling time may have contributed to this low burden.

Validating an Air Traffic Management Concept of Operation Using Statistical Modeling

NASA Technical Reports Server (NTRS)

He, Yuning; Davies, Misty Dawn

2013-01-01

Validating a concept of operation for a complex, safety-critical system (like the National Airspace System) is challenging because of the high dimensionality of the controllable parameters and the infinite number of states of the system. In this paper, we use statistical modeling techniques to explore the behavior of a conflict detection and resolution algorithm designed for the terminal airspace. These techniques predict the robustness of the system simulation to both nominal and off-nominal behaviors within the overall airspace. They also can be used to evaluate the output of the simulation against recorded airspace data. Additionally, the techniques carry with them a mathematical value of the worth of each prediction-a statistical uncertainty for any robustness estimate. Uncertainty Quantification (UQ) is the process of quantitative characterization and ultimately a reduction of uncertainties in complex systems. UQ is important for understanding the influence of uncertainties on the behavior of a system and therefore is valuable for design, analysis, and verification and validation. In this paper, we apply advanced statistical modeling methodologies and techniques on an advanced air traffic management system, namely the Terminal Tactical Separation Assured Flight Environment (T-TSAFE). We show initial results for a parameter analysis and safety boundary (envelope) detection in the high-dimensional parameter space. For our boundary analysis, we developed a new sequential approach based upon the design of computer experiments, allowing us to incorporate knowledge from domain experts into our modeling and to determine the most likely boundary shapes and its parameters. We carried out the analysis on system parameters and describe an initial approach that will allow us to include time-series inputs, such as the radar track data, into the analysis

Real time measurement of transient event emissions of air toxics by tomographic remote sensing in tandem with mobile monitoring

NASA Astrophysics Data System (ADS)

Olaguer, Eduardo P.; Stutz, Jochen; Erickson, Matthew H.; Hurlock, Stephen C.; Cheung, Ross; Tsai, Catalina; Colosimo, Santo F.; Festa, James; Wijesinghe, Asanga; Neish, Bradley S.

2017-02-01

During the Benzene and other Toxics Exposure (BEE-TEX) study, a remote sensing network based on long path Differential Optical Absorption Spectroscopy (DOAS) was set up in the Manchester neighborhood beside the Ship Channel of Houston, Texas in order to perform Computer Aided Tomography (CAT) scans of hazardous air pollutants. On 18-19 February 2015, the CAT scan network detected large nocturnal plumes of toluene and xylenes most likely associated with railcar loading and unloading operations at Ship Channel petrochemical facilities. The presence of such plumes during railcar operations was confirmed by a mobile laboratory equipped with a Proton Transfer Reaction-Mass Spectrometer (PTR-MS), which measured transient peaks of toluene and C2-benzenes of 50 ppb and 57 ppb respectively around 4 a.m. LST on 19 February 2015. Plume reconstruction and source attribution were performed using the 4D variational data assimilation technique and a 3D micro-scale forward and adjoint air quality model based on both tomographic and PTR-MS data. Inverse model estimates of fugitive emissions associated with railcar transfer emissions ranged from 2.0 to 8.2 kg/hr for toluene and from 2.2 to 3.5 kg/hr for xylenes in the early morning of 19 February 2015.

Meeting report: Estimating the benefits of reducing hazardous air pollutants--summary of 2009 workshop and future considerations.

PubMed

Gwinn, Maureen R; Craig, Jeneva; Axelrad, Daniel A; Cook, Rich; Dockins, Chris; Fann, Neal; Fegley, Robert; Guinnup, David E; Helfand, Gloria; Hubbell, Bryan; Mazur, Sarah L; Palma, Ted; Smith, Roy L; Vandenberg, John; Sonawane, Babasaheb

2011-01-01

Quantifying the benefits of reducing hazardous air pollutants (HAPs, or air toxics) has been limited by gaps in toxicological data, uncertainties in extrapolating results from high-dose animal experiments to estimate human effects at lower doses, limited ambient and personal exposure monitoring data, and insufficient economic research to support valuation of the health impacts often associated with exposure to individual air toxics. To address some of these issues, the U.S. Environmental Protection Agency held the Workshop on Estimating the Benefits of Reducing Hazardous Air Pollutants (HAPs) in Washington, DC, from 30 April to 1 May 2009. Experts from multiple disciplines discussed how best to move forward on air toxics benefits assessment, with a focus on developing near-term capability to conduct quantitative benefits assessment. Proposed methodologies involved analysis of data-rich pollutants and application of this analysis to other pollutants, using dose-response modeling of animal data for estimating benefits to humans, determining dose-equivalence relationships for different chemicals with similar health effects, and analysis similar to that used for criteria pollutants. Limitations and uncertainties in economic valuation of benefits assessment for HAPS were discussed as well. These discussions highlighted the complexities in estimating the benefits of reducing air toxics, and participants agreed that alternative methods for benefits assessment of HAPs are needed. Recommendations included clearly defining the key priorities of the Clean Air Act air toxics program to identify the most effective approaches for HAPs benefits analysis, focusing on susceptible and vulnerable populations, and improving dose-response estimation for quantification of benefits.

Organic carbon content effects on bioavailability of pyrethroid insecticides and validation of solid phase extraction with Poly (2,6-diphenyl-p-phenylene oxide) Polymer by Daphnia magna toxicity tests.

PubMed

Feo, M L; Corcellas, C; Barata, C; Ginebreda, A; Eljarrat, E; Barceló, D

2013-01-01

Solid phase extraction with Poly (2,6-diphenyl-p-phenylene oxide) Polymer (Tenax) was used for determining the bioavailability of eleven pyrethroids in field collected sediments with different organic carbon content (OC). The bioavailable fraction of pyrethroids decreased with increasing OC in sediments; the percentages of desorption ranged from 10 to 20% for sediment with higher OC content (5.8%) and 15-40% for that with lower OC (2%). Generally pyrethroids showed low bioavailability and cyfluthrin resulted to be the most bioavailable among the studied pyrethroids. Acute toxicity tests with Daphnia magna were carried out on sediment spiked with three selected pyrethroids (λ-cyhalothrin, cypermethrin and deltamethrin) and served to validate the efficiency of Tenax as a method for assessing the bioavailability of pyrethroids. Toxicity test demonstrated that Tenax was able to remove the toxic bio-available fraction of pyrethroids in sediment. Extracts from Tenax beads after the desorption experiments and spiked sediment before desorption had an equivalent toxicity (LC50) to D. magna neonates at 48 and 72 h of exposure. These results indicate that Tenax beds can be used to predict bio-available and toxic fractions of pyrethroids sorbed to sediments to aquatic organisms like D. magna. Copyright © 2012 Elsevier B.V. All rights reserved.

Investigation of Various Novel Air-Breathing Propulsion Systems

NASA Astrophysics Data System (ADS)

Wilhite, Jarred M.

The current research investigates the operation and performance of various air-breathing propulsion systems, which are capable of utilizing different types of fuel. This study first focuses on a modular RDE configuration, which was mainly studied to determine which conditions yield stable, continuous rotating detonation for an ethylene-air mixture. The performance of this RDE was analyzed by studying various parameters such as mass flow rate, equivalence ratios, wave speed and cell size. For relatively low mass flow rates near stoichiometric conditions, a rotating detonation wave is observed for an ethylene-RDE, but at speeds less than an ideal detonation wave. The current research also involves investigating the newly designed, Twin Oxidizer Injection Capable (TOXIC) RDE. Mixtures of hydrogen and air were utilized for this configuration, resulting in sustained rotating detonation for various mass flow rates and equivalence ratios. A thrust stand was also developed to observe and further measure the performance of the TOXIC RDE. Further analysis was conducted to accurately model and simulate the response of thrust stand during operation of the RDE. Also included in this research are findings and analysis of a propulsion system capable of operating on the Inverse Brayton Cycle. The feasibility of this novel concept was validated in a previous study to be sufficient for small-scale propulsion systems, namely UAV applications. This type of propulsion system consists of a reorganization of traditional gas turbine engine components, which incorporates expansion before compression. This cycle also requires a heat exchanger to reduce the temperature of the flow entering the compressor downstream. While adding a heat exchanger improves the efficiency of the cycle, it also increases the engine weight, resulting in less endurance for the aircraft. Therefore, this study focuses on the selection and development of a new heat exchanger design that is lightweight, and is capable

US EPA Office of Research and Development Community-Focused Exposure and Risk Screening Tool (C-FERST) Air web mapping service

EPA Pesticide Factsheets

This map service displays all air-related layers used in the USEPA Community/Tribal-Focused Exposure and Risk Screening Tool (C/T-FERST) mapping application (https://www.epa.gov/c-ferst). The following data sources (and layers) are contained in this service:USEPA's 2005 National-Scale Air Toxic Assessment (NATA) data. Data are shown at the census tract level (2000 census tract boundaries, US Census Bureau) for Cumulative Cancer and Non-Cancer risks (Neurological and Respiratory) from 139 air toxics. In addition, individual pollutant estimates of Ambient Concentration, Exposure Concentration, Cancer, and Non-Cancer risks (Neurological and Respiratory) are provided for: Acetaldehyde, Acrolein, Arsenic, Benzene, 1,3-Butadiene, Chromium, Diesel PM, Formaldehyde, Lead, Naphthalene, and Polycyclic Aromatic Hydrocarbon (PAH). The original Access tables were downloaded from USEPA's Office of Air and Radiation (OAR) https://www.epa.gov/national-air-toxics-assessment/2005-national-air-toxics-assessment. The data classification (defined interval) for this map service was developed for USEPA's Office of Research and Development's (ORD) Community-Focused Exposure and Risk Screening Tool (C-FERST) per guidance provided by OAR.The 2005 NATA provides information on 177 of the 187 Clean Air Act air toxics (https://www.epa.gov/sites/production/files/2015-10/documents/2005-nata-pollutants.pdf) plus diesel particulate matter (diesel PM was assessed for non-cancer only). For addit

Twenty years of measurement of polycyclic aromatic hydrocarbons (PAHs) in UK ambient air by nationwide air quality networks.

PubMed

Brown, Andrew S; Brown, Richard J C; Coleman, Peter J; Conolly, Christopher; Sweetman, Andrew J; Jones, Kevin C; Butterfield, David M; Sarantaridis, Dimitris; Donovan, Brian J; Roberts, Ian

2013-06-01

The impact of human activities on the health of the population and of the wider environment has prompted action to monitor the presence of toxic compounds in the atmosphere. Toxic organic micropollutants (TOMPs) are some of the most insidious and persistent of these pollutants. Since 1991 the United Kingdom has operated nationwide air quality networks to assess the presence of TOMPs, including polycyclic aromatic hydrocarbons (PAHs), in ambient air. The data produced in 2010 marked 20 years of nationwide PAH monitoring. This paper marks this milestone by providing a novel and critical review of the data produced since nationwide monitoring began up to the end of 2011 (the latest year for which published data is available), discussing how the networks performing this monitoring has evolved, and elucidating trends in the concentrations of the PAHs measured. The current challenges in the area and a forward look to the future of air quality monitoring for PAHs are also discussed briefly.

Effect of clothing type on validity of air-displacement plethysmography.

PubMed

King, George A; Fulkerson, Bethany; Evans, Michael J; Moreau, Kerrie L; McLaughlin, James E; Thompson, Dixie L

2006-02-01

The purpose of the study was to evaluate the validity of an air-displacement plethysmography system (AP) within the general population, while wearing (1) a racing-type swimsuit (AP(SS)) and (2) participant's personal undergarments (AP(UG)), against hydrodensitometry (HW). Fifty women and 50 men were measured for body volume, density, and fat percentage by HW and compared with AP(SS) and AP(UG). For women, AP(UG) and AP(SS) were similar, although significant differences (p < 0.001) were observed between AP(UG) and HW and between AP(SS) and HW. For men, there was no significant difference between AP(UG) and HW; however, significant differences (P < or = 0.01) were found between AP(UG) and AP(SS) and between AP(SS) and HW. The small discrepancy in measured values between AP and HW are within the measurement error for the instrumentation and these data support the use of AP for determination of body composition in adults across a wide range of body size (body mass index [BMI] 17.7-35.2 kg.m(-2)) and age (18-57 y). Participants' personal undergarments provide a practical alternative to a spandex swimsuit when measuring body composition by AP in women but not in men.

Spatial-temporal and cancer risk assessment of selected hazardous air pollutants in Seattle.

PubMed

Wu, Chang-fu; Liu, L-J Sally; Cullen, Alison; Westberg, Hal; Williamson, John

2011-01-01

In the Seattle Air Toxics Monitoring Pilot Program, we measured 15 hazardous air pollutants (HAPs) at 6 sites for more than a year between 2000 and 2002. Spatial-temporal variations were evaluated with random-effects models and principal component analyses. The potential health risks were further estimated based on the monitored data, with the incorporation of the bootstrapping technique for the uncertainty analysis. It is found that the temporal variability was generally higher than the spatial variability for most air toxics. The highest temporal variability was observed for tetrachloroethylene (70% temporal vs. 34% spatial variability). Nevertheless, most air toxics still exhibited significant spatial variations, even after accounting for the temporal effects. These results suggest that it would require operating multiple air toxics monitoring sites over a significant period of time with proper monitoring frequency to better evaluate population exposure to HAPs. The median values of the estimated inhalation cancer risks ranged between 4.3 × 10⁻⁵ and 6.0 × 10⁻⁵, with the 5th and 95th percentile levels exceeding the 1 in a million level. VOCs as a whole contributed over 80% of the risk among the HAPs measured and arsenic contributed most substantially to the overall risk associated with metals. Copyright © 2010 Elsevier Ltd. All rights reserved.

An automated microphysiological assay for toxicity evaluation.

PubMed

Eggert, S; Alexander, F A; Wiest, J

2015-08-01

Screening a newly developed drug, food additive or cosmetic ingredient for toxicity is a critical preliminary step before it can move forward in the development pipeline. Due to the sometimes dire consequences when a harmful agent is overlooked, toxicologists work under strict guidelines to effectively catalogue and classify new chemical agents. Conventional assays involve long experimental hours and many manual steps that increase the probability of user error; errors that can potentially manifest as inaccurate toxicology results. Automated assays can overcome many potential mistakes that arise due to human error. In the presented work, we created and validated a novel, automated platform for a microphysiological assay that can examine cellular attributes with sensors measuring changes in cellular metabolic rate, oxygen consumption, and vitality mediated by exposure to a potentially toxic agent. The system was validated with low buffer culture medium with varied conductivities that caused changes in the measured impedance on integrated impedance electrodes.

MULTIDISCIPLINARY APPROACH TO TOXICOLOGICAL SCREENING: II. DEVELOPMENTAL TOXICITY

EPA Science Inventory

As part of the validation of an integrated bioassay for systemic, neuro-, and developmental toxicity, we evaluated the responses of Fischer-344 rats to four pesticides, four chlorinated solvents, and two other industrial chemicals. he pesticides included carbaryl, triadimefon, ch...

Validation of air traffic controller workload models

DOT National Transportation Integrated Search

1979-09-01

During the past several years, computer models have been developed for off-site : estimat ion of control ler's workload. The inputs to these models are audio and : digital data normally recorded at an Air Route Traffic Control Center (ARTCC). : This ...

Rethink potential risks of toxic emissions from natural gas and oil mining.

PubMed

Meng, Qingmin

2018-09-01

Studies have showed the increasing environmental and public health risks of toxic emissions from natural gas and oil mining, which have become even worse as fracking is becoming a dominant approach in current natural gas extraction. However, governments and communities often overlook the serious air pollutants from oil and gas mining, which are often quantified lower than the significant levels of adverse health effects. Therefore, we are facing a challenging dilemma: how could we clearly understand the potential risks of air toxics from natural gas and oil mining. This short study aims at the design and application of simple and robust methods to enhance and improve current understanding of the becoming worse toxic air emissions from natural gas and oil mining as fracking is becoming the major approach. Two simple ratios, the min-to-national-average and the max-to-national-average, are designed and applied to each type of air pollutants in a natural gas and oil mining region. The two ratios directly indicate how significantly high a type of air pollutant could be due to natural gas and oil mining by comparing it to the national average records, although it may not reach the significant risks of adverse health effects according to current risk screening methods. The min-to-national-average and the max-to-national-average ratios can be used as a direct and powerful method to describe the significance of air pollution by comparing it to the national average. The two ratios are easy to use for governments, stakeholders, and the public to pay enough attention on the air pollutants from natural gas and oil mining. The two ratios can also be thematically mapped at sampled sites for spatial monitoring, but spatial mitigation and analysis of environmental and health risks need other measurements of environmental and demographic characteristics across a natural gas and oil mining area. Copyright © 2018 Elsevier Ltd. All rights reserved.

Atmospheric deposition exposes Qinling pandas to toxic pollutants.

PubMed

Chen, Yi-Ping; Zheng, Ying-Juan; Liu, Qiang; Song, Yi; An, Zhi-Sheng; Ma, Qing-Yi; Ellison, Aaron M

2017-03-01

The giant panda (Ailuropoda melanoleuca) is one of the most endangered animals in the world, and it is recognized worldwide as a symbol for conservation. A previous study showed that wild and captive pandas, especially those of the Qinling subspecies, were exposed to toxicants in their diet of bamboo; the ultimate origin of these toxicants is unknown. Here we show that atmospheric deposition is the most likely origin of heavy metals and persistent organic pollutants (POPs) in the diets of captive and wild Qinling pandas. Average atmospheric deposition was 199, 115, and 49 g·m -2 ·yr -1 in the center of Xi'an City, at China's Shaanxi Wild Animal Research Center (SWARC), and at Foping National Nature Reserve (FNNR), respectively. Atmospheric deposition of heavy metals (As, Cd, Cr, Pb, Hg, Co, Cu, Zn, Mn, and Ni) and POPs was highest at Xi'an City, intermediate at SWARC, and lowest at FNNR. Soil concentrations of the aforementioned heavy metals other than As and Zn also were significantly higher at SWARC than at FNNR. Efforts to conserve Qinling pandas may be compromised by air pollution attendant to China's economic development. Improvement of air quality and reductions of toxic emissions are urgently required to protect China's iconic species. © 2017 by the Ecological Society of America.

Air Pollution Monitoring Site Selection by Multiple Criteria Decision Analysis

EPA Science Inventory

Criteria air pollutants (particulate matter, sulfur dioxide, oxides of nitrogen, volatile organic compounds, and carbon monoxide) as well as toxic air pollutants are a global concern. A particular scenario that is receiving increased attention in the research is the exposure to t...

Dietary and pharmacological intervention to mitigate the cardiopulmonary effects of air pollution toxicity.

PubMed

Tong, Haiyan

2016-12-01

Exposure to air pollution contributes importantly to excess morbidity and mortality. And while regulatory actions under the "Clean Air Act" have saved millions of lives by improving air quality, there are still millions of people in the U.S. who live in areas where particulate air pollution (PM) levels exceed the U.S. Environmental Protection Agency's National Ambient Air Quality Standards. Therefore, apart from such localities working to attain such standards the protection of the health of public and in particular those at high risk might benefit from interventional strategies that would ameliorate air pollution's adverse health effects. Because inflammation and oxidative stress appear to mediate the health effects of air pollution, one interventional approach to consider is the use of dietary supplementation or medication with anti-inflammatory or antioxidant properties to block the biological responses that initiate the pathophysiological process that culminates in adverse health effects. This article reviews the capability of dietary supplementation, such as antioxidant vitamins, polyunsaturated fatty acids, and medications as a strategy to mitigate air pollution-induced subclinical cardiopulmonary effects. Antioxidant vitamins C and E protect the lungs against short-term ozone and PM exposure. Polyunsaturated fatty acids, such as fish oil and olive oil appear to offer protection against short-term air pollution-induced adverse cardiovascular responses. Taking dietary supplements or medications with antioxidant or anti-inflammatory properties has the potential to provide at least partial protection against air pollution-induced adverse health effects in those individuals who are known to be most susceptible, namely those with pre-existing respiratory and cardiovascular diseases. This article is part of a Special Issue entitled Air Pollution, edited by Wenjun Ding, Andrew J. Ghio and Weidong Wu. Copyright © 2016. Published by Elsevier B.V.

BUILDING FEATURES THAT INFLUENCE THE PENETRATION OF TOXIC GASES FROM THE AMBIENT TO THE INDOOR ENVIRONMENT

EPA Science Inventory

Strategies to reduce indoor exposures to certain toxic air contaminants suggested a study of the penetration of these toxics from the external atmosphere into an unoccupied research house. The mass balance method is applied to measure rates of sorption and re-emission of the con...

Evaluation of passenger health risk assessment of sustainable indoor air quality monitoring in metro systems based on a non-Gaussian dynamic sensor validation method.

PubMed

Kim, MinJeong; Liu, Hongbin; Kim, Jeong Tai; Yoo, ChangKyoo

2014-08-15

Sensor faults in metro systems provide incorrect information to indoor air quality (IAQ) ventilation systems, resulting in the miss-operation of ventilation systems and adverse effects on passenger health. In this study, a new sensor validation method is proposed to (1) detect, identify and repair sensor faults and (2) evaluate the influence of sensor reliability on passenger health risk. To address the dynamic non-Gaussianity problem of IAQ data, dynamic independent component analysis (DICA) is used. To detect and identify sensor faults, the DICA-based squared prediction error and sensor validity index are used, respectively. To restore the faults to normal measurements, a DICA-based iterative reconstruction algorithm is proposed. The comprehensive indoor air-quality index (CIAI) that evaluates the influence of the current IAQ on passenger health is then compared using the faulty and reconstructed IAQ data sets. Experimental results from a metro station showed that the DICA-based method can produce an improved IAQ level in the metro station and reduce passenger health risk since it more accurately validates sensor faults than do conventional methods. Copyright © 2014 Elsevier B.V. All rights reserved.

Assessment of dioxin-like activity in ambient air particulate matter using recombinant yeast assays

NASA Astrophysics Data System (ADS)

Olivares, Alba; van Drooge, Barend L.; Pérez Ballesta, Pascual; Grimalt, Joan O.; Piña, Benjamin

2011-01-01

Ectopic activation of the aryl hydrocarbon receptor (AhR), also known as dioxin-like activity, is a major component of the toxicity associated with polycyclic aromatic hydrocarbons (PAH). Filtration of ambient air particulate matter through PM 10 filters followed by chemical determination of PAH concentrations and a yeast-based bioassay (RYA) were combined to evaluate and characterize dioxin-like activity in ambient air. Samples were collected in a semirural area of Northern Italy between September 2008 and February 2009. Total PAH contents ranged between 0.3 ng m -3 and 34 ng m -3 and were in correlation with seasonal variations of meteorological conditions and combustion processes. Dioxin-like activity values in air samples showed an excellent correlation (0.71 < R2 < 0.86) with the observed PAH concentrations and the predicted toxicity equivalents for PAH. This RYA-bioassay reported in the present study provides a simple and low-cost routine control for toxic PAH emissions, even at background air concentration levels.

Australia’s first national level quantitative environmental justice assessment of industrial air pollution

NASA Astrophysics Data System (ADS)

Chakraborty, Jayajit; Green, Donna

2014-04-01

This study presents the first national level quantitative environmental justice assessment of industrial air pollution in Australia. Specifically, our analysis links the spatial distribution of sites and emissions associated with industrial pollution sources derived from the National Pollution Inventory, to Indigenous status and social disadvantage characteristics of communities derived from Australian Bureau of Statistics indicators. Our results reveal a clear national pattern of environmental injustice based on the locations of industrial pollution sources, as well as volume, and toxicity of air pollution released at these locations. Communities with the highest number of polluting sites, emission volume, and toxicity-weighted air emissions indicate significantly greater proportions of Indigenous population and higher levels of socio-economic disadvantage. The quantities and toxicities of industrial air pollution are particularly higher in communities with the lowest levels of educational attainment and occupational status. These findings emphasize the need for more detailed analysis in specific regions and communities where socially disadvantaged groups are disproportionately impacted by industrial air pollution. Our empirical findings also underscore the growing necessity to incorporate environmental justice considerations in environmental planning and policy-making in Australia.

NMR-based urine analysis in rats: prediction of proximal tubule kidney toxicity and phospholipidosis.

PubMed

Lienemann, Kai; Plötz, Thomas; Pestel, Sabine

2008-01-01

The aim of safety pharmacology is early detection of compound-induced side-effects. NMR-based urine analysis followed by multivariate data analysis (metabonomics) identifies efficiently differences between toxic and non-toxic compounds; but in most cases multiple administrations of the test compound are necessary. We tested the feasibility of detecting proximal tubule kidney toxicity and phospholipidosis with metabonomics techniques after single compound administration as an early safety pharmacology approach. Rats were treated orally, intravenously, inhalatively or intraperitoneally with different test compounds. Urine was collected at 0-8 h and 8-24 h after compound administration, and (1)H NMR-patterns were recorded from the samples. Variation of post-processing and feature extraction methods led to different views on the data. Support Vector Machines were trained on these different data sets and then aggregated as experts in an Ensemble. Finally, validity was monitored with a cross-validation study using a training, validation, and test data set. Proximal tubule kidney toxicity could be predicted with reasonable total classification accuracy (85%), specificity (88%) and sensitivity (78%). In comparison to alternative histological studies, results were obtained quicker, compound need was reduced, and very importantly fewer animals were needed. In contrast, the induction of phospholipidosis by the test compounds could not be predicted using NMR-based urine analysis or the previously published biomarker PAG. NMR-based urine analysis was shown to effectively predict proximal tubule kidney toxicity after single compound administration in rats. Thus, this experimental design allows early detection of toxicity risks with relatively low amounts of compound in a reasonably short period of time.

PLANNING OF HEALTH EFFECTS RESEARCH ON HAZARDOUS AIR POLLUTANTS AND APPLICATION TO RISK ASSESSMENT PROBLEMS

EPA Science Inventory

The Clean Air Act Amendment of 1990 designated a set of compounds as hazardous air pollutants or "air toxics" which may be released into the air from a variety of sources including stationary, mobile and indoor air sources. Determination of the risks to human health from exposur...

U. S. Environmental Protection Agency's inhalation RFD methodology: Risk assessment for air toxics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jarabek, A.M.; Menache, M.G.; Overton, J.H.

1989-01-01

The U.S. Environmental Protection Agency (U.S. EPA) has advocated the establishment of general and scientific guidelines for the evaluation of toxicological data and their use in deriving benchmark values to protect exposed populations from adverse health effects. The Agency's reference dose (RfD) methodology for deriving benchmark values for noncancer toxicity originally addressed risk assessment of oral exposures. The paper presents a brief background on the development of the inhalation reference dose (RFDi) methodology, including concepts and issues related to addressing the dynamics of the respiratory system as the portal of entry. Different dosimetric adjustments are described that were incorporated intomore » the methodology to account for the nature of the inhaled agent (particle or gas) and the site of the observed toxic effects (respiratory or extrarespiratory). Impacts of these adjustments on the extrapolation of toxicity data of inhaled agents for human health risk assessment and future research directions are also discussed.« less

Quantitative structure-toxicity relationship (QSTR) studies on the organophosphate insecticides.

PubMed

Can, Alper

2014-11-04

Organophosphate insecticides are the most commonly used pesticides in the world. In this study, quantitative structure-toxicity relationship (QSTR) models were derived for estimating the acute oral toxicity of organophosphate insecticides to male rats. The 20 chemicals of the training set and the seven compounds of the external testing set were described by means of using descriptors. Descriptors for lipophilicity, polarity and molecular geometry, as well as quantum chemical descriptors for energy were calculated. Model development to predict toxicity of organophosphate insecticides in different matrices was carried out using multiple linear regression. The model was validated internally and externally. In the present study, QSTR model was used for the first time to understand the inherent relationships between the organophosphate insecticide molecules and their toxicity behavior. Such studies provide mechanistic insight about structure-toxicity relationship and help in the design of less toxic insecticides. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

40 CFR 80.910 - How does a refiner or importer apply for a toxics baseline?

Code of Federal Regulations, 2011 CFR

2011-07-01

... section no later than June 30, 2001, or 3 months prior to the first introduction of gasoline into commerce... (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Baseline... type of gasoline, per § 80.815(b), calculated in accordance with § 80.915; (ii) The baseline toxics...

40 CFR 80.910 - How does a refiner or importer apply for a toxics baseline?

Code of Federal Regulations, 2010 CFR

2010-07-01

... section no later than June 30, 2001, or 3 months prior to the first introduction of gasoline into commerce... (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Toxics Baseline... type of gasoline, per § 80.815(b), calculated in accordance with § 80.915; (ii) The baseline toxics...

Protecting wilderness air quality in the United States

Treesearch

K. A. Tonnessen

2000-01-01

Federal land managers are responsible for protecting air quality-related values (AQRVs) in parks and wilderness areas from air pollution damage or impairment. Few, if any, class 1 areas are unaffected by regional and global pollutants, such as visibility-reducing particles, ozone and deposition of sulfur (S), nitrogen (N) and toxics. This paper lays out the basic...

EMISSIONS OF AIR TOXICS FROM A SIMULATED CHARCOAL KILN

EPA Science Inventory

The report gives results of experiments in a laboratory-scale charcoal kiln simulator to evaluate emissions of hazardous air pollutants from the production of charcoal in Missouri-type kilns. Fixed combustion gases were measured using continuous monitors. In Addition, other pollu...

In silico prediction of Tetrahymena pyriformis toxicity for diverse industrial chemicals with substructure pattern recognition and machine learning methods.

PubMed

Cheng, Feixiong; Shen, Jie; Yu, Yue; Li, Weihua; Liu, Guixia; Lee, Philip W; Tang, Yun

2011-03-01

There is an increasing need for the rapid safety assessment of chemicals by both industries and regulatory agencies throughout the world. In silico techniques are practical alternatives in the environmental hazard assessment. It is especially true to address the persistence, bioaccumulative and toxicity potentials of organic chemicals. Tetrahymena pyriformis toxicity is often used as a toxic endpoint. In this study, 1571 diverse unique chemicals were collected from the literature and composed of the largest diverse data set for T. pyriformis toxicity. Classification predictive models of T. pyriformis toxicity were developed by substructure pattern recognition and different machine learning methods, including support vector machine (SVM), C4.5 decision tree, k-nearest neighbors and random forest. The results of a 5-fold cross-validation showed that the SVM method performed better than other algorithms. The overall predictive accuracies of the SVM classification model with radial basis functions kernel was 92.2% for the 5-fold cross-validation and 92.6% for the external validation set, respectively. Furthermore, several representative substructure patterns for characterizing T. pyriformis toxicity were also identified via the information gain analysis methods. Copyright © 2010 Elsevier Ltd. All rights reserved.

Alternatives to animal testing: research, trends, validation, regulatory acceptance.

PubMed

Huggins, Jane

2003-01-01

Current trends and issues in the development of alternatives to the use of animals in biomedical experimentation are discussed in this position paper. Eight topics are considered and include refinement of acute toxicity assays; eye corrosion/irritation alternatives; skin corrosion/irritation alternatives; contact sensitization alternatives; developmental/reproductive testing alternatives; genetic engineering (transgenic) assays; toxicogenomics; and validation of alternative methods. The discussion of refinement of acute toxicity assays is focused primarily on developments with regard to reduction of the number of animals used in the LD(50) assay. However, the substitution of humane endpoints such as clinical signs of toxicity for lethality in these assays is also evaluated. Alternative assays for eye corrosion/irritation as well as those for skin corrosion/irritation are described with particular attention paid to the outcomes, both successful and unsuccessful, of several validation efforts. Alternative assays for contact sensitization and developmental/reproductive toxicity are presented as examples of methods designed for the examination of interactions between toxins and somewhat more complex physiological systems. Moreover, genetic engineering and toxicogenomics are discussed with an eye toward the future of biological experimentation in general. The implications of gene manipulation for research animals, specifically, are also examined. Finally, validation methods are investigated as to their effectiveness, or lack thereof, and suggestions for their standardization and improvement, as well as implementation are reviewed.

Toxic terror

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whelan, E.M.

A review of toxic materials in the environment explores the evolution of public awareness of the problem, public and governmental reaction, the effort to establish standards of safe levels and danger thresholds, and the struggle to implement and enforce environmental policy. Separate chapters deal with environmental premises and scientific realities, the DDT debate and birth of environmentalism, the disaster of Love Canal, pesticides, PCBs, PBBs, formaldehyde, dioxin, air pollution, water pollution, nuclear energy and radioactive materials, acid rain, and the status of American health. The book concludes with a chapter on the need for scientific research and hard evidence tomore » either prove or disprove the pessimism of those who warn of a threat to human health and survival.« less

New toxics, new poverty: a social understanding of the freebase cocaine/Paco in Buenos Aires, Argentina.

PubMed

Epele, María E

2011-01-01

Included within the field of research on changes in drug use patterns and vulnerability are conditions of emergency related to economic crisis, wars, and political conflict. This study addresses the complex connections between the rapid propagation of freebase cocaine (FBC)-locally known as "pasta base" or "Paco" in Argentina and the normalization of the consequences of Argentina's 2001-2002 political-economic crisis. On the basis of the results of an ethnographic study carried out in three neighborhoods of the Greater Buenos Aires area between 2001 and 2005, this article aims to analyze how changes in the material and social living conditions are interrelated with the high toxicity of FBC/Paco and engender the emerging compulsion of its consumption and deterioration to the bodies, subjectivities, and social activities of active drug users from these shantytowns. By analyzing the changes in transactions directly or indirectly involving drugs-specifically those ranging from cocaine to FBC/Paco-we can argue how structural poverty, "new poverty," is not only associated with the expansion of FBC/Paco but is also shaped by its use, modes of consumption, associated health problems, and sufferings.

Review of the Reported Measures of Clinical Validity and Clinical Utility as Arguments for the Implementation of Pharmacogenetic Testing: A Case Study of Statin-Induced Muscle Toxicity.

PubMed

Jansen, Marleen E; Rigter, T; Rodenburg, W; Fleur, T M C; Houwink, E J F; Weda, M; Cornel, Martina C

2017-01-01

Advances from pharmacogenetics (PGx) have not been implemented into health care to the expected extent. One gap that will be addressed in this study is a lack of reporting on clinical validity and clinical utility of PGx-tests. A systematic review of current reporting in scientific literature was conducted on publications addressing PGx in the context of statins and muscle toxicity. Eighty-nine publications were included and information was selected on reported measures of effect, arguments, and accompanying conclusions. Most authors report associations to quantify the relationship between a genetic variation an outcome, such as adverse drug responses. Conclusions on the implementation of a PGx-test are generally based on these associations, without explicit mention of other measures relevant to evaluate the test's clinical validity and clinical utility. To gain insight in the clinical impact and select useful tests, additional outcomes are needed to estimate the clinical validity and utility, such as cost-effectiveness.

Biofiltration: An innovative air pollution control technology for VOC emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leson, G.; Winer, A.M.

1991-08-01

Biofiltration is a relatively recent air pollution control (APC) technology in which off-gases containing biodegradable volatile organic compounds (VOC) or inorganic air toxics are vented through a biologically active material. This technology has been successfully applied in Germany and The Netherlands in many full-scale applications to control odors, VOC and air toxic emissions from a wide range of industrial and public sector sources. Control efficiencies of more than 90 percent have been achieved for many common air pollutants. Due to lower operating costs, biofiltration can provide significant economic advantages over other APC technologies if applied to off-gases that contain readilymore » biodegradable pollutants in low concentrations. Environmental benefits include low energy requirements and the avoidance of cross media transfer of pollutants. This paper reviews the history and current status of biofiltration, outlines its underlying scientific and engineering principles, and discusses the applicability of biofilters for a wide range of specific emission sources.« less

Biofiltration: an innovative air pollution control technology for VOC emissions.

PubMed

Leson, G; Winer, A M

1991-08-01

Biofiltration is a relatively recent air pollution control (APC) technology in which off-gases containing biodegradable volatile organic compounds (VOC) or inorganic air toxics are vented through a biologically active material. This technology has been successfully applied in Germany and The Netherlands in many full-scale applications to control odors, VOC and air toxic emissions from a wide range of industrial and public sector sources. Control efficiencies of more than 90 percent have been achieved for many common air pollutants. Due to lower operating costs, biofiltration can provide significant economic advantages over other APC technologies if applied to off-gases that contain readily biodegradable pollutants in low concentrations. Environmental benefits include low energy requirements and the avoidance of cross media transfer of pollutants. This paper reviews the history and current status of biofiltration, outlines its underlying scientific and engineering principles, and discusses the applicability of biofilters for a wide range of specific emission sources.

Effects of synthetic and natural toxicants on livestock.

PubMed

Shull, L R; Cheeke, P R

1983-07-01

Synthetic and natural toxicants are constituents of soil, air, water and foodstuffs. Their impact on animal agriculture has resulted from acute and chronic intoxication and residues transferred into meat, dairy and poultry products. Recent advances in analytical chemistry and the sciences associated with toxicology have allowed better assessment of the hazard of toxicants on animals including man. Historically, natural toxicants (phytotoxins, mycotoxins and minerals) that are associated with many common feedstuffs accounted for toxicity episodes of epidemic proportions. Most synthetic chemicals (pesticides, nonpesticidal organic chemicals and drugs) have been introduced in increasing numbers since the 1940's. In the 1960's and '70's, recognition of the need to control their environmental distribution stimulated the introduction of numerous laws and regulations. In the last decade, several problematic synthetic chemicals have been banned, particularly those found to persist in the environment or those confirmed or suspected as carcinogens in humans. At the farm level, the development of various preventative management strategies has decreased the exposure of livestock to natural toxicants. In the future, the impact of natural toxicants on animal agriculture is expected to lessen as their existence, etiology and toxicology are determined. On the other hand, synthetic chemicals will continue to threaten animal health as greater numbers and quantities are released into the environment. These challenges should stimulate a greater involvement of animal scientists in toxicology.

SIMULATING URBAN AIR TOXICS OVER CONTINENTAL AND URBAN SCALES

EPA Science Inventory

The US EPA is evaluating a version of the CMAQ model to support risk assessment for the exposure to Hazardous Air Pollutants (HAPs). The model uses a variant of the CB4 chemical mechanism to simulate ambient concentrations of twenty HAPs that exist primarily as gaseous compounds...

The effect of ambient cadmium air pollution on the hair mineral content of children.

PubMed

Stewart-Pinkham, S M

1989-01-01

Hair analyses of 80 children with learning and behavioral problems were assessed by age, sex, season, place of residence, exposure to passive smoke and excess contact with known cadmium air pollutant sources. All children had been exposed for at least 2 years to air pollution from a refuse-derived fuel incineration plant. All of the patients had increased hair cadmium compared with a control group, but there was a strong seasonal influence on hair cadmium. Exposure to cadmium was ubiquitous. A neurobehavioral toxic effect was found in children who showed evidence of inhibition of pyrimidine-5'-nucleotidase by low hair phosphorus levels and low zinc levels in whom there was enhanced lead absorption. Hair analyses appear to be a useful biological monitor for detecting toxic effects from ambient air cadmium levels in subsets of the population at risk for heavy metal toxicity. Air filter measurements appear worthless for detecting environmental contamination with cadmium in air with low levels of lead. Trees, on the other hand, which are more adversely affected by cadmium than other heavy metals, show evidence of inhibition of pyrimidine-5'-nucleosidase by excess seeding.

Design, development and validation of a new laryngo-pharyngeal endoscopic esthesiometer and range-finder based on the assessment of air-pulse variability determinants.

PubMed

Giraldo-Cadavid, Luis F; Agudelo-Otalora, Luis Mauricio; Burguete, Javier; Arbulu, Mario; Moscoso, William Daniel; Martínez, Fabio; Ortiz, Andrés Felipe; Diaz, Juan; Pantoja, Jaime A; Rueda-Arango, Andrés Felipe; Fernández, Secundino

2016-05-10

Laryngo-pharyngeal mechano-sensitivity (LPMS) is involved in dysphagia, sleep apnea, stroke, irritable larynx syndrome and cough hypersensitivity syndrome among other disorders. These conditions are associated with a wide range of airway reflex abnormalities. However, the current device for exploring LPMS is limited because it assesses only the laryngeal adductor reflex during fiber-optic endoscopic evaluations of swallowing and requires a high degree of expertise to obtain reliable results, introducing intrinsic expert variability and subjectivity. We designed, developed and validated a new air-pulse laryngo-pharyngeal endoscopic esthesiometer with a built-in laser range-finder (LPEER) based on the evaluation and control of air-pulse variability determinants and on intrinsic observer variability and subjectivity determinants of the distance, angle and site of stimulus impact. The LPEER was designed to be capable of delivering precise and accurate stimuli with a wide range of intensities that can explore most laryngo-pharyngeal reflexes. We initially explored the potential factors affecting the reliability of LPMS tests and included these factors in a multiple linear regression model. The following factors significantly affected the precision and accuracy of the test (P < 0.001): the tube conducting the air-pulses, the supply pressure of the system, the duration of the air-pulses, and the distance and angle between the end of the tube conducting the air-pulses and the site of impact. To control all of these factors, an LPEER consisting of an air-pulse generator and an endoscopic laser range-finder was designed and manufactured. We assessed the precision and accuracy of the LPEER's stimulus and range-finder according to the coefficient of variation (CV) and by looking at the differences between the measured properties and the desired values, and we performed a pilot validation on ten human subjects. The air-pulses and range-finder exhibited good precision and

Prediction of the effect of formulation on the toxicity of chemicals.

PubMed

Mistry, Pritesh; Neagu, Daniel; Sanchez-Ruiz, Antonio; Trundle, Paul R; Vessey, Jonathan D; Gosling, John Paul

2017-01-01

Two approaches for the prediction of which of two vehicles will result in lower toxicity for anticancer agents are presented. Machine-learning models are developed using decision tree, random forest and partial least squares methodologies and statistical evidence is presented to demonstrate that they represent valid models. Separately, a clustering method is presented that allows the ordering of vehicles by the toxicity they show for chemically-related compounds.

CFD validation experiments for hypersonic flows

NASA Technical Reports Server (NTRS)

Marvin, Joseph G.

1992-01-01

A roadmap for CFD code validation is introduced. The elements of the roadmap are consistent with air-breathing vehicle design requirements and related to the important flow path components: forebody, inlet, combustor, and nozzle. Building block and benchmark validation experiments are identified along with their test conditions and measurements. Based on an evaluation criteria, recommendations for an initial CFD validation data base are given and gaps identified where future experiments could provide new validation data.

RESOLVING NEIGHBORHOOD-SCALE AIR TOXICS MODELING: A CASE STUDY IN WILMINGTON, CALIFORNIA

EPA Science Inventory

Air quality modeling is useful for characterizing exposures to air pollutants. While models typically provide results on regional scales, there is a need for refined modeling approaches capable of resolving concentrations on the scale of tens of meters, across modeling domains 1...

AIR Model Preflight Analysis

NASA Technical Reports Server (NTRS)

Tai, H.; Wilson, J. W.; Maiden, D. L.

2003-01-01

The atmospheric ionizing radiation (AIR) ER-2 preflight analysis, one of the first attempts to obtain a relatively complete measurement set of the high-altitude radiation level environment, is described in this paper. The primary thrust is to characterize the atmospheric radiation and to define dose levels at high-altitude flight. A secondary thrust is to develop and validate dosimetric techniques and monitoring devices for protecting aircrews. With a few chosen routes, we can measure the experimental results and validate the AIR model predictions. Eventually, as more measurements are made, we gain more understanding about the hazardous radiation environment and acquire more confidence in the prediction models.

Environmental Health Risks and Housing Values: Evidence from 1,600 Toxic Plant Openings and Closings.

PubMed

Currie, Janet; Davis, Lucas; Greenstone, Michael; Walker, Reed

2015-02-01

Regulatory oversight of toxic emissions from industrial plants and understanding about these emissions' impacts are in their infancy. Applying a research design based on the openings and closings of 1,600 industrial plants to rich data on housing markets and infant health, we find that: toxic air emissions affect air quality only within 1 mile of the plant; plant openings lead to 11 percent declines in housing values within 0.5 mile or a loss of about $4.25 million for these households; and a plant's operation is associated with a roughly 3 percent increase in the probability of low birthweight within 1 mile.

Environmental Health Risks and Housing Values: Evidence from 1,600 Toxic Plant Openings and Closings†

PubMed Central

Currie, Janet; Davis, Lucas; Greenstone, Michael

2016-01-01

Regulatory oversight of toxic emissions from industrial plants and understanding about these emissions’ impacts are in their infancy. Applying a research design based on the openings and closings of 1,600 industrial plants to rich data on housing markets and infant health, we find that: toxic air emissions affect air quality only within 1 mile of the plant; plant openings lead to 11 percent declines in housing values within 0.5 mile or a loss of about $4.25 million for these households; and a plant’s operation is associated with a roughly 3 percent increase in the probability of low birthweight within 1 mile. PMID:27134284

Treatment of reverse osmosis (RO) concentrate by the combined Fe/Cu/air and Fenton process (1stFe/Cu/air-Fenton-2ndFe/Cu/air).

PubMed

Ren, Yi; Yuan, Yue; Lai, Bo; Zhou, Yuexi; Wang, Juling

2016-01-25

To decompose or transform the toxic and refractory reverse osmosis (RO) concentrate and improve the biodegradability, 1stFe/Cu/air-Fenton-2ndFe/Cu/air were developed to treat RO concentrate obtained from an amino acid production plant in northern China. First, their operating conditions were optimized thoroughly. Furthermore, 5 control experiments were setup to confirm the superiority of 1stFe/Cu/air-Fenton-2ndFe/Cu/air and synergistic reaction between Fe/Cu/air and Fenton. The results suggest that the developed method could obtain high COD removal (65.1%) and BOD5/COD ratio (0.26) due to the synergistic reaction between Fe/Cu/air and Fenton. Under the optimal conditions, the influent and effluent of 1stFe/Cu/air-Fenton-2ndFe/Cu/air and 5 control experiments were analyzed by using UV, FTIR, EEM and LC, which confirm the superiority of 1stFe/Cu/air-Fenton-2ndFe/Cu/air. Therefore, the developed method in this study is a promising process for treatment of RO concentrate. Copyright © 2015 Elsevier B.V. All rights reserved.

Validity and validation of expert (Q)SAR systems.

PubMed

Hulzebos, E; Sijm, D; Traas, T; Posthumus, R; Maslankiewicz, L

2005-08-01

At a recent workshop in Setubal (Portugal) principles were drafted to assess the suitability of (quantitative) structure-activity relationships ((Q)SARs) for assessing the hazards and risks of chemicals. In the present study we applied some of the Setubal principles to test the validity of three (Q)SAR expert systems and validate the results. These principles include a mechanistic basis, the availability of a training set and validation. ECOSAR, BIOWIN and DEREK for Windows have a mechanistic or empirical basis. ECOSAR has a training set for each QSAR. For half of the structural fragments the number of chemicals in the training set is >4. Based on structural fragments and log Kow, ECOSAR uses linear regression to predict ecotoxicity. Validating ECOSAR for three 'valid' classes results in predictivity of > or = 64%. BIOWIN uses (non-)linear regressions to predict the probability of biodegradability based on fragments and molecular weight. It has a large training set and predicts non-ready biodegradability well. DEREK for Windows predictions are supported by a mechanistic rationale and literature references. The structural alerts in this program have been developed with a training set of positive and negative toxicity data. However, to support the prediction only a limited number of chemicals in the training set is presented to the user. DEREK for Windows predicts effects by 'if-then' reasoning. The program predicts best for mutagenicity and carcinogenicity. Each structural fragment in ECOSAR and DEREK for Windows needs to be evaluated and validated separately.

PACSIN2 polymorphism influences TPMT activity and mercaptopurine-related gastrointestinal toxicity.

PubMed

Stocco, Gabriele; Yang, Wenjian; Crews, Kristine R; Thierfelder, William E; Decorti, Giuliana; Londero, Margherita; Franca, Raffaella; Rabusin, Marco; Valsecchi, Maria Grazia; Pei, Deqing; Cheng, Cheng; Paugh, Steven W; Ramsey, Laura B; Diouf, Barthelemy; McCorkle, Joseph Robert; Jones, Terreia S; Pui, Ching-Hon; Relling, Mary V; Evans, William E

2012-11-01

Treatment-related toxicity can be life-threatening and is the primary cause of interruption or discontinuation of chemotherapy for acute lymphoblastic leukemia (ALL), leading to an increased risk of relapse. Mercaptopurine is an essential component of continuation therapy in all ALL treatment protocols worldwide. Genetic polymorphisms in thiopurine S-methyltransferase (TPMT) are known to have a marked effect on mercaptopurine metabolism and toxicity; however, some patients with wild-type TPMT develop toxicity during mercaptopurine treatment for reasons that are not well understood. To identify additional genetic determinants of mercaptopurine toxicity, a genome-wide analysis was performed in a panel of human HapMap cell lines to identify trans-acting genes whose expression and/or single-nucleotide polymorphisms (SNPs) are related to TPMT activity, then validated in patients with ALL. The highest ranking gene with both mRNA expression and SNPs associated with TPMT activity in HapMap cell lines was protein kinase C and casein kinase substrate in neurons 2 (PACSIN2). The association of a PACSIN2 SNP (rs2413739) with TPMT activity was confirmed in patients and knock-down of PACSIN2 mRNA in human leukemia cells (NALM6) resulted in significantly lower TPMT activity. Moreover, this PACSIN2 SNP was significantly associated with the incidence of severe gastrointestinal (GI) toxicity during consolidation therapy containing mercaptopurine, and remained significant in a multivariate analysis including TPMT and SLCO1B1 as covariates, consistent with its influence on TPMT activity. The association with GI toxicity was also validated in a separate cohort of pediatric patients with ALL. These data indicate that polymorphism in PACSIN2 significantly modulates TPMT activity and influences the risk of GI toxicity associated with mercaptopurine therapy.

PACSIN2 polymorphism influences TPMT activity and mercaptopurine-related gastrointestinal toxicity

PubMed Central

Stocco, Gabriele; Yang, Wenjian; Crews, Kristine R.; Thierfelder, William E.; Decorti, Giuliana; Londero, Margherita; Franca, Raffaella; Rabusin, Marco; Valsecchi, Maria Grazia; Pei, Deqing; Cheng, Cheng; Paugh, Steven W.; Ramsey, Laura B.; Diouf, Barthelemy; McCorkle, Joseph Robert; Jones, Terreia S.; Pui, Ching-Hon; Relling, Mary V.; Evans, William E.

2012-01-01

Treatment-related toxicity can be life-threatening and is the primary cause of interruption or discontinuation of chemotherapy for acute lymphoblastic leukemia (ALL), leading to an increased risk of relapse. Mercaptopurine is an essential component of continuation therapy in all ALL treatment protocols worldwide. Genetic polymorphisms in thiopurine S-methyltransferase (TPMT) are known to have a marked effect on mercaptopurine metabolism and toxicity; however, some patients with wild-type TPMT develop toxicity during mercaptopurine treatment for reasons that are not well understood. To identify additional genetic determinants of mercaptopurine toxicity, a genome-wide analysis was performed in a panel of human HapMap cell lines to identify trans-acting genes whose expression and/or single-nucleotide polymorphisms (SNPs) are related to TPMT activity, then validated in patients with ALL. The highest ranking gene with both mRNA expression and SNPs associated with TPMT activity in HapMap cell lines was protein kinase C and casein kinase substrate in neurons 2 (PACSIN2). The association of a PACSIN2 SNP (rs2413739) with TPMT activity was confirmed in patients and knock-down of PACSIN2 mRNA in human leukemia cells (NALM6) resulted in significantly lower TPMT activity. Moreover, this PACSIN2 SNP was significantly associated with the incidence of severe gastrointestinal (GI) toxicity during consolidation therapy containing mercaptopurine, and remained significant in a multivariate analysis including TPMT and SLCO1B1 as covariates, consistent with its influence on TPMT activity. The association with GI toxicity was also validated in a separate cohort of pediatric patients with ALL. These data indicate that polymorphism in PACSIN2 significantly modulates TPMT activity and influences the risk of GI toxicity associated with mercaptopurine therapy. PMID:22846425

Environmental toxicants and autism spectrum disorders: a systematic review

PubMed Central

Rossignol, D A; Genuis, S J; Frye, R E

2014-01-01

Although the involvement of genetic abnormalities in autism spectrum disorders (ASD) is well-accepted, recent studies point to an equal contribution by environmental factors, particularly environmental toxicants. However, these toxicant-related studies in ASD have not been systematically reviewed to date. Therefore, we compiled publications investigating potential associations between environmental toxicants and ASD and arranged these publications into the following three categories: (a) studies examining estimated toxicant exposures in the environment during the preconceptional, gestational and early childhood periods; (b) studies investigating biomarkers of toxicants; and (c) studies examining potential genetic susceptibilities to toxicants. A literature search of nine electronic scientific databases through November 2013 was performed. In the first category examining ASD risk and estimated toxicant exposures in the environment, the majority of studies (34/37; 92%) reported an association. Most of these studies were retrospective case–control, ecological or prospective cohort studies, although a few had weaker study designs (for example, case reports or series). Toxicants implicated in ASD included pesticides, phthalates, polychlorinated biphenyls (PCBs), solvents, toxic waste sites, air pollutants and heavy metals, with the strongest evidence found for air pollutants and pesticides. Gestational exposure to methylmercury (through fish exposure, one study) and childhood exposure to pollutants in water supplies (two studies) were not found to be associated with ASD risk. In the second category of studies investigating biomarkers of toxicants and ASD, a large number was dedicated to examining heavy metals. Such studies demonstrated mixed findings, with only 19 of 40 (47%) case–control studies reporting higher concentrations of heavy metals in blood, urine, hair, brain or teeth of children with ASD compared with controls. Other biomarker studies reported that

Tropospheric ozone toxicity vs. usefulness of ozone therapy.

PubMed

Bocci, Velio Alvaro

2007-02-01

There is a general consensus that continuous inhalation of air polluted with ozone is detrimental for the lungs and vital organs. Even if the concentration of tropospheric ozone is slightly above the tolerated dose, toxicity ensues owing to the cumulative dose inhaled for months. However, in medicine ozone is used as a real drug and a precise concentration and therapeutic dosage must be calibrated against the antioxidant capacity of blood. As ozone reacts with blood, it generates pharmacological messengers such as H(2)O(2) and lipid oxidation products (LOPs). These activate several biochemical pathways in blood cells, which after reinfusion are responsible for therapeutic activities lasting several days. Neither acute nor chronic toxicity has been registered.

Development of an in-line filter to prevent intrusion of NO2 toxic vapors into A/C systems

NASA Technical Reports Server (NTRS)

Meneghelli, Barry; Mcnulty, R. J.; Springer, Mike; Lueck, Dale E.

1995-01-01

The hypergolic propellant nitrogen tetroxide (N2O4 or NTO) is routinely used in spacecraft launched at Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS). In the case of a catastrophic failure of the spacecraft, there would be a release of the unspent propellant in the form of a toxic cloud. Inhalation of this material at downwind concentrations which may be as high as 20 parts per million (ppm) for 30 minutes in duration, may produce irritation to the eyes, nose and respiratory tract. Studies at both KSC and CCAS have shown that the indoor concentrations of N2O4 during a toxic release may range from 1 to 15 ppm and depend on the air change rate (ACR) for a particular building and whether or not the air conditioning (A/C) system has been shut down or left in an operating mode. This project was initiated in order to assess how current A/C systems could be easily modified to prevent personnel from being exposed to toxic vapors. A sample system has been constructed to test the ability of several types of filter material to capture the N2O4 vapors prior to their infiltration into the A/C system. Test results will be presented which compare the efficiencies of standard A/C filters, water wash systems, and chemically impregnated filter material in taking toxic vapors out of the incoming air stream.

Validity of ambient levels of fine particles as surrogate for personal exposure to outdoor air pollution--results of the European EXPOLIS-EAS Study (Swiss Center Basel).

PubMed

Oglesby, L; Künzli, N; Röösli, M; Braun-Fahrländer, C; Mathys, P; Stern, W; Jantunen, M; Kousa, A

2000-07-01

To evaluate the validity of fixed-site fine particle levels as exposure surrogates in air pollution epidemiology, we considered four indicator groups: (1) PM2.5 total mass concentrations, (2) sulfur and potassium for regional air pollution, (3) lead and bromine for traffic-related particles, and (4) calcium for crustal particles. Using data from the European EXPOLIS (Air Pollution Exposure Distribution within Adult Urban Populations in Europe) study, we assessed the associations between 48-hr personal exposures and home outdoor levels of the indicators. Furthermore, within-city variability of fine particle levels was evaluated. Personal exposures to PM2.5 mass were not correlated to corresponding home outdoor levels (n = 44, rSpearman (Sp) = 0.07). In the group reporting neither relevant indoor sources nor relevant activities, personal exposures and home outdoor levels of sulfur were highly correlated (n = 40, rSp = 0.85). In contrast, the associations were weaker for traffic (Pb: n = 44, rSp = 0.53; Br: n = 44, rSp = 0.21) and crustal (Ca: n = 44, rSp = 0.12) indicators. This contrast is consistent with spatially homogeneous regional pollution and higher spatial variability of traffic and crustal indicators observed in Basel, Switzerland. We conclude that for regional air pollution, fixed-site fine particle levels are valid exposure surrogates. For source-specific exposures, however, fixed-site data are probably not the optimal measure. Still, in air pollution epidemiology, ambient PM2.5 levels may be more appropriate exposure estimates than total personal PM2.5 exposure, since the latter reflects a mixture of indoor and outdoor sources.

Clean Air Act, TRI drive emission reduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heller, K.

1994-06-22

When asked to rank priority environmental engineering projects, many chemical firms put emissions reduction first. The chief motivators are the need to comply with rules governing major sources of hazardous air pollutants (HAPS) under the Clean Air Act Amendments of 1990 (CAA), along with the need to reduce the volumes of chemicals on EPA`s Toxics Release Inventory (TRI). Deep-welling of toxics is getting special attention as the practice adds considerably to TRI numbers. {open_quotes}We want to eliminate our air toxics so that we can get entirely out of the [CAA] Maximum Achievable Control Technology (MACT) requirements,{close_quotes} says Thomas Zosel, manager/pollutionmore » prevention programs for 3M (St. Paul, MN). He estimates that 3M`s 1993 total research expenditures for environmental improvements were at least $200 million, out of an annual research budget of a little more than $1 billion. And, he says, the spending level is not expected to drop. Among its many efforts, 3M is striving to move away from solvents in all of its processes. To help reach that goal, the company developed a {open_quotes}waste measurement metric{close_quotes} that calculates the wastes produced by each of the company`s 50 operating divisions. In the case of Magic Tape, the company eliminated solvent emission by switching to a water-based adhesive that does not require a solvent.« less

Predicting the risk of toxic blooms of golden alga from cell abundance and environmental covariates

USGS Publications Warehouse

Patino, Reynaldo; VanLandeghem, Matthew M.; Denny, Shawn

2016-01-01

Golden alga (Prymnesium parvum) is a toxic haptophyte that has caused considerable ecological damage to marine and inland aquatic ecosystems worldwide. Studies focused primarily on laboratory cultures have indicated that toxicity is poorly correlated with the abundance of golden alga cells. This relationship, however, has not been rigorously evaluated in the field where environmental conditions are much different. The ability to predict toxicity using readily measured environmental variables and golden alga abundance would allow managers rapid assessments of ichthyotoxicity potential without laboratory bioassay confirmation, which requires additional resources to accomplish. To assess the potential utility of these relationships, several a priori models relating lethal levels of golden alga ichthyotoxicity to golden alga abundance and environmental covariates were constructed. Model parameters were estimated using archived data from four river basins in Texas and New Mexico (Colorado, Brazos, Red, Pecos). Model predictive ability was quantified using cross-validation, sensitivity, and specificity, and the relative ranking of environmental covariate models was determined by Akaike Information Criterion values and Akaike weights. Overall, abundance was a generally good predictor of ichthyotoxicity as cross validation of golden alga abundance-only models ranged from ∼ 80% to ∼ 90% (leave-one-out cross-validation). Environmental covariates improved predictions, especially the ability to predict lethally toxic events (i.e., increased sensitivity), and top-ranked environmental covariate models differed among the four basins. These associations may be useful for monitoring as well as understanding the abiotic factors that influence toxicity during blooms.

EMISSION FACTORS FOR IRON AND STEEL SOURCES: CRITERIA AND TOXIC POLLUTANTS

EPA Science Inventory

The report provides a comprehensive set of emission factors for sources of both criteria and toxic air pollutants in integrated iron and steel plants and specialty electric arc shops (minimills). Emission factors are identified for process sources, and process and open source fug...

Standardized toxicity testing may underestimate ecotoxicity: Environmentally relevant food rations increase the toxicity of silver nanoparticles to Daphnia.

PubMed

Stevenson, Louise M; Krattenmaker, Katherine E; Johnson, Erica; Bowers, Alexandra J; Adeleye, Adeyemi S; McCauley, Edward; Nisbet, Roger M

2017-11-01

Daphnia in the natural environment experience fluctuations in algal food supply, with periods when algal populations bloom and seasons when Daphnia have very little algal food. Standardized chronic toxicity tests, used for ecological risk assessment, dictate that Daphnia must be fed up to 400 times more food than they would experience in the natural environment (outside of algal blooms) for a toxicity test to be valid. This disconnect can lead to underestimating the toxicity of a contaminant. We followed the growth, reproduction, and survival of Daphnia exposed to 75 and 200 µg/L silver nanoparticles (AgNPs) at 4 food rations for up to 99 d and found that AgNP exposure at low, environmentally relevant food rations increased the toxicity of AgNPs. Exposure to AgNP at low food rations decreased the survival and/or reproduction of individuals, with potential consequences for Daphnia populations (based on calculated specific population growth rates). We also found tentative evidence that a sublethal concentration of AgNPs (75 µg/L) caused Daphnia to alter energy allocation away from reproduction and toward survival and growth. The present findings emphasize the need to consider resource availability, and not just exposure, in the environment when estimating the effect of a toxicant. Environ Toxicol Chem 2017;36:3008-3018. © 2017 SETAC. © 2017 SETAC.

78 FR 22198 - Approval and Promulgation of Air Quality Implementation Plans; Charlotte, Raleigh/Durham and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-15

... CONTACT: Richard Wong, Regulatory Development Section, Air Planning Branch, Air, Pesticides and Toxics... organic compounds. Dated: April 3, 2013. A. Stanley Meiburg, Acting Regional Administrator, Region 4. 0...

Financial validation of the European Society of Thoracic Surgeons risk score predicting prolonged air leak after video-assisted thoracic surgery lobectomy.

PubMed

Brunelli, Alessandro; Pompili, Cecilia; Dinesh, Padma; Bassi, Vinod; Imperatori, Andrea

2018-04-27

The objective of this study was to verify whether the European Society of Thoracic Surgeons prolonged air leak risk score for video-assisted thoracoscopic lobectomy was associated with incremental postoperative costs. We retrospectively analyzed 353 patients subjected to video-assisted thoracoscopic lobectomy or segmentectomy (April 2014 to March 2016). Postoperative costs were obtained from the hospital Finance Department. Patients were grouped in different classes of risk according to their prolonged air leak risk score. To verify the independent association of the prolonged air leak risk score with postoperative costs, we performed a stepwise multivariable regression analysis in which the dependent variable was postoperative cost. Prolonged air leak developed in 56 patients (15.9%). Their length of stay was 3 days longer compared with those without prolonged air leak (8.3 vs 5.4, P < .0001). Their postoperative cost was higher than that of patients without prolonged air leak: $5939.8 versus $4381.7 (P = .001). After grouping the patients according to their prolonged air leak risk score, prolonged air leak incidence was 12.3% in class A, 13.7% in class B, 28.8% in class C, and 22.2% in class D (P = .020). The average postoperative cost was $4031.0 in class A, $4498.2 in class B, $6146.6 in class C, and $6809.3 in class D (analysis of variance test, P < .001). Multivariable regression analysis showed that being in classes C and D of PAL score (P = .001) and the presence of cardiopulmonary complications (P < .0001) were the only independent factors significantly associated with postoperative costs. We financially validated the European Society of Thoracic Surgeons prolonged air leak risk score for video-assisted thoracoscopic lobectomies, which appears useful in selecting those patients in whom the application of additional intraoperative interventions to avoid prolonged air leak may be more cost-effective. Copyright © 2018 The American Association

Random Forests to Predict Rectal Toxicity Following Prostate Cancer Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ospina, Juan D.; INSERM, U1099, Rennes; Escuela de Estadística, Universidad Nacional de Colombia Sede Medellín, Medellín

2014-08-01

Purpose: To propose a random forest normal tissue complication probability (RF-NTCP) model to predict late rectal toxicity following prostate cancer radiation therapy, and to compare its performance to that of classic NTCP models. Methods and Materials: Clinical data and dose-volume histograms (DVH) were collected from 261 patients who received 3-dimensional conformal radiation therapy for prostate cancer with at least 5 years of follow-up. The series was split 1000 times into training and validation cohorts. A RF was trained to predict the risk of 5-year overall rectal toxicity and bleeding. Parameters of the Lyman-Kutcher-Burman (LKB) model were identified and a logistic regression modelmore » was fit. The performance of all the models was assessed by computing the area under the receiving operating characteristic curve (AUC). Results: The 5-year grade ≥2 overall rectal toxicity and grade ≥1 and grade ≥2 rectal bleeding rates were 16%, 25%, and 10%, respectively. Predictive capabilities were obtained using the RF-NTCP model for all 3 toxicity endpoints, including both the training and validation cohorts. The age and use of anticoagulants were found to be predictors of rectal bleeding. The AUC for RF-NTCP ranged from 0.66 to 0.76, depending on the toxicity endpoint. The AUC values for the LKB-NTCP were statistically significantly inferior, ranging from 0.62 to 0.69. Conclusions: The RF-NTCP model may be a useful new tool in predicting late rectal toxicity, including variables other than DVH, and thus appears as a strong competitor to classic NTCP models.« less

Paper-based chromatic toxicity bioassay by analysis of bacterial ferricyanide reduction.

PubMed

Pujol-Vila, F; Vigués, N; Guerrero-Navarro, A; Jiménez, S; Gómez, D; Fernández, M; Bori, J; Vallès, B; Riva, M C; Muñoz-Berbel, X; Mas, J

2016-03-03

Water quality assessment requires a continuous and strict analysis of samples to guarantee compliance with established standards. Nowadays, the increasing number of pollutants and their synergistic effects lead to the development general toxicity bioassays capable to analyse water pollution as a whole. Current general toxicity methods, e.g. Microtox(®), rely on long operation protocols, the use of complex and expensive instrumentation and sample pre-treatment, which should be transported to the laboratory for analysis. These requirements delay sample analysis and hence, the response to avoid an environmental catastrophe. In an attempt to solve it, a fast (15 min) and low-cost toxicity bioassay based on the chromatic changes associated to bacterial ferricyanide reduction is here presented. E. coli cells (used as model bacteria) were stably trapped on low-cost paper matrices (cellulose-based paper discs, PDs) and remained viable for long times (1 month at -20 °C). Apart from bacterial carrier, paper matrices also acted as a fluidic element, allowing fluid management without the need of external pumps. Bioassay evaluation was performed using copper as model toxic agent. Chromatic changes associated to bacterial ferricyanide reduction were determined by three different transduction methods, i.e. (i) optical reflectometry (as reference method), (ii) image analysis and (iii) visual inspection. In all cases, bioassay results (in terms of half maximal effective concentrations, EC50) were in agreement with already reported data, confirming the good performance of the bioassay. The validation of the bioassay was performed by analysis of real samples from natural sources, which were analysed and compared with a reference method (i.e. Microtox). Obtained results showed agreement for about 70% of toxic samples and 80% of non-toxic samples, which may validate the use of this simple and quick protocol in the determination of general toxicity. The minimum instrumentation

A systematic review of validated methods for identifying erythema multiforme major/minor/not otherwise specified, Stevens-Johnson Syndrome, or toxic epidermal necrolysis using administrative and claims data.

PubMed

Schneider, Gary; Kachroo, Sumesh; Jones, Natalie; Crean, Sheila; Rotella, Philip; Avetisyan, Ruzan; Reynolds, Matthew W

2012-01-01

The Food and Drug Administration's (FDA) Mini-Sentinel pilot program aims to conduct active surveillance to refine safety signals that emerge for marketed medical products. A key facet of this surveillance is to develop and understand the validity of algorithms for identifying health outcomes of interest (HOIs) from administrative and claims data. This paper summarizes the process and findings of the algorithm review of erythema multiforme and related conditions. PubMed and Iowa Drug Information Service searches were conducted to identify citations applicable to the erythema multiforme HOI. Level 1 abstract reviews and Level 2 full-text reviews were conducted to find articles that used administrative and claims data to identify erythema multiforme, Stevens-Johnson syndrome, or toxic epidermal necrolysis and that included validation estimates of the coding algorithms. Our search revealed limited literature focusing on erythema multiforme and related conditions that provided administrative and claims data-based algorithms and validation estimates. Only four studies provided validated algorithms and all studies used the same International Classification of Diseases code, 695.1. Approximately half of cases subjected to expert review were consistent with erythema multiforme and related conditions. Updated research needs to be conducted on designing validation studies that test algorithms for erythema multiforme and related conditions and that take into account recent changes in the diagnostic coding of these diseases. Copyright © 2012 John Wiley & Sons, Ltd.

Assessment and prediction of air quality using fuzzy logic and autoregressive models

NASA Astrophysics Data System (ADS)

Carbajal-Hernández, José Juan; Sánchez-Fernández, Luis P.; Carrasco-Ochoa, Jesús A.; Martínez-Trinidad, José Fco.

2012-12-01

In recent years, artificial intelligence methods have been used for the treatment of environmental problems. This work, presents two models for assessment and prediction of air quality. First, we develop a new computational model for air quality assessment in order to evaluate toxic compounds that can harm sensitive people in urban areas, affecting their normal activities. In this model we propose to use a Sigma operator to statistically asses air quality parameters using their historical data information and determining their negative impact in air quality based on toxicity limits, frequency average and deviations of toxicological tests. We also introduce a fuzzy inference system to perform parameter classification using a reasoning process and integrating them in an air quality index describing the pollution levels in five stages: excellent, good, regular, bad and danger, respectively. The second model proposed in this work predicts air quality concentrations using an autoregressive model, providing a predicted air quality index based on the fuzzy inference system previously developed. Using data from Mexico City Atmospheric Monitoring System, we perform a comparison among air quality indices developed for environmental agencies and similar models. Our results show that our models are an appropriate tool for assessing site pollution and for providing guidance to improve contingency actions in urban areas.

Evaluation of copper toxicity using site specific algae and water chemistry: Field validation of laboratory bioassays.

PubMed

Fawaz, Elyssa G; Salam, Darine A; Kamareddine, Lina

2018-07-15

Studies of metal toxicity to microalgae have predominantly been conducted using single non-target algae species and without due regard for the chemistry of the treated waters, leading to ineffective or excessive algaecide treatments. In this study, indigenous multi-algal species (Scenedesmus quadricauda, and Scenedesmus subspicatus and Oscillatoria agardhii) were used in laboratory toxicity bioassays under simulated field water chemistry (pH = 7.2, hardness = 196 mg L -1 as CaCO 3 , and alkalinity = 222 mg L -1 as CaCO 3 ) to determine the optimum copper sulfate treatment dose to control algae growth in an irrigation canal. Toxicity bioassays were conducted using copper sulfate in chelated (with EDTA) and non-chelated (without EDTA) forms to assess the influence of the use of synthetic chelators in toxicity studies. Also, copper toxicity to the indigenous algae species was measured in the non-modified EPA test medium (pH = 7.5, hardness = 92 mg L -1 as CaCO 3 , alkalinity = 10 mg L -1 as CaCO 3 and EDTA= 300 µg L -1 ) to assess the impact of the water chemistry on algae inhibitory algal dosages. Under simulated water chemistry conditions, lower toxicity was measured in the test flasks with the chelated form of copper (96 h- EC 50 = 386.67 µg L -1 as Cu) as compared to those with the non-chelated metal (96 h-EC 50 = 217.17 µg L -1 as Cu). In addition, higher copper toxicity was measured in the test flasks prepared with the non-modified EPA medium using chelated copper (96 h-EC 50 = 65.93 µg L -1 as Cu) as compared to their analogous microcosms with modified water chemistry (96 h-EC 50 = 386.67 µg L -1 as Cu), the increased water hardness and alkalinity in the latter case contributing to the decrease of the metal bioavailability. Results from laboratory experiments showed good correlation with copper dosages used in a small scale field testing to control algae growth, increasing confidence in

Development of novel in silico model for developmental toxicity assessment by using naïve Bayes classifier method.

PubMed

Zhang, Hui; Ren, Ji-Xia; Kang, Yan-Li; Bo, Peng; Liang, Jun-Yu; Ding, Lan; Kong, Wei-Bao; Zhang, Ji

2017-08-01

Toxicological testing associated with developmental toxicity endpoints are very expensive, time consuming and labor intensive. Thus, developing alternative approaches for developmental toxicity testing is an important and urgent task in the drug development filed. In this investigation, the naïve Bayes classifier was applied to develop a novel prediction model for developmental toxicity. The established prediction model was evaluated by the internal 5-fold cross validation and external test set. The overall prediction results for the internal 5-fold cross validation of the training set and external test set were 96.6% and 82.8%, respectively. In addition, four simple descriptors and some representative substructures of developmental toxicants were identified. Thus, we hope the established in silico prediction model could be used as alternative method for toxicological assessment. And these obtained molecular information could afford a deeper understanding on the developmental toxicants, and provide guidance for medicinal chemists working in drug discovery and lead optimization. Copyright © 2017 Elsevier Inc. All rights reserved.

“A Reduced-form Model to Estimate Near-road Air Quality for Communities: the Community Line Source modeling system (C-LINE)”

EPA Science Inventory

The paper presents the Community Line Source (C-LINE) modeling system that estimates toxic air pollutant (air toxics) concentration gradients within 500 meters of busy roadways for community-sized areas on the order of 100 km2. C-LINE accesses publicly available datasets with nat...

Fact Sheet - Final Air Toxics Rule for Gold Mine Ore Processing and Production

EPA Pesticide Factsheets

Fact sheet summarizing main points of National Emissions Standards for Hazardous Air Pollutants for gold ore processing and production facilities, the seventh largest source of mercury air emission in the United States.

The generalized Sellmeier equation for air

PubMed Central

Voronin, A. A.; Zheltikov, A. M.

2017-01-01

We present a compact, uniform generalized Sellmeier-equation (GSE) description of air refraction and its dispersion that remains highly accurate within an ultrabroad spectral range from the ultraviolet to the long-wavelength infrared. While the standard Sellmeier equation (SSE) for atmospheric air is not intended for the description of air refractivity in the mid-infrared and long-wavelength infrared, failing beyond, roughly 2.5 μm, our generalization of this equation is shown to agree remarkably well with full-scale air-refractivity calculations involving over half a million atmospheric absorption lines, providing a highly accurate description of air refractivity in the range of wavelengths from 0.3 to 13 μm. With its validity range being substantially broader than the applicability range of the SSE and its accuracy being at least an order of magnitude higher than the accuracy that the SSE can provide even within its validity range, the GSE-based approach offers a powerful analytical tool for the rapidly progressing mid- and long-wavelength-infrared optics of the atmosphere. PMID:28836624

STEMS-Air: a simple GIS-based air pollution dispersion model for city-wide exposure assessment.

PubMed

Gulliver, John; Briggs, David

2011-05-15

Current methods of air pollution modelling do not readily meet the needs of air pollution mapping for short-term (i.e. daily) exposure studies. The main limiting factor is that for those few models that couple with a GIS there are insufficient tools for directly mapping air pollution both at high spatial resolution and over large areas (e.g. city wide). A simple GIS-based air pollution model (STEMS-Air) has been developed for PM(10) to meet these needs with the option to choose different exposure averaging periods (e.g. daily and annual). STEMS-Air uses the grid-based FOCALSUM function in ArcGIS in conjunction with a fine grid of emission sources and basic information on meteorology to implement a simple Gaussian plume model of air pollution dispersion. STEMS-Air was developed and validated in London, UK, using data on concentrations of PM(10) from routinely available monitoring data. Results from the validation study show that STEMS-Air performs well in predicting both daily (at four sites) and annual (at 30 sites) concentrations of PM(10). For daily modelling, STEMS-Air achieved r(2) values in the range 0.19-0.43 (p<0.001) based solely on traffic-related emissions and r(2) values in the range 0.41-0.63 (p<0.001) when adding information on 'background' levels of PM(10). For annual modelling of PM(10), the model returned r(2) in the range 0.67-0.77 (P<0.001) when compared with monitored concentrations. The model can thus be used for rapid production of daily or annual city-wide air pollution maps either as a screening process in urban air quality planning and management, or as the basis for health risk assessment and epidemiological studies. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Assessment of Airborne Particles. Fundamentals, Applications, and Implications to Inhalation Toxicity.

ERIC Educational Resources Information Center

Mercer, Thomas T., Ed.; And Others

Concern over chemical and radioactive particulate matter in industry and over rapidly increasing air pollution has stimulated research both on the properties of airborne particles and methods for assessing them and on their biological effects following inhalation. The Third Rochester International Conference on Environmental Toxicity was,…

Speciation Profiles and Toxic Emission Factors for Nonroad Engines: DRAFT REPORT

EPA Science Inventory

This document details the research and development behind how MOVES2014a estimates air toxic emissions for nonroad engines and equipment run on conventional gasoline without ethanol (E0) and gasoline blended with 10% ethanol (E10) as well as diesel fuel, compressed natural gas (C...

Validity of Ambient Levels of Fine Particles as Surrogate for Personal Exposure to Outdoor Air Pollution-Results of the European EXPOLIS-EAS Study (Swiss Center Basel).

PubMed

Oglesby, Lucy; Künzli, Nino; Röösli, Martin; Braun-Fahrländer, Charlotte; Mathys, Patrick; Stern, Willem; Jantunen, Matti; Kousa, Anu

2000-07-01

To evaluate the validity of fixed-site fine particle levels as exposure surrogates in air pollution epidemiology, we considered four indicator groups: (1) PM 25 total mass concentrations, (2) sulfur and potassium for regional air pollution, (3) lead and bromine for traffic-related particles, and (4) calcium for crustal particles. Using data from the European EXPOLIS (Air Pollution Exposure Distribution within Adult Urban Populations in Europe) study, we assessed the associations between 48-hr personal exposures and home outdoor levels of the indicators. Furthermore, within-city variability of fine particle levels was evaluated. Personal exposures to PM 2.5 mass were not correlated to corresponding home outdoor levels (n = 44, r S (S) =r o v ' Spearman (Sp) 0.07). In the group reporting neither relevant indoor sources nor relevant activities, personal exposures and home outdoor levels of sulfur were highly correlated (n = 40, r Sp = 0.85). In contrast, the associations were weaker for traffic (Pb: n = 44, r Sp = 0.53; Br: n = 44, r Sp = 0.21) and crustal (Ca: n = 44, r Sp = 0.12) indicators. This contrast is consistent with spatially homogeneous regional pollution and higher spatial variability of traffic and crustal indicators observed in Basel, Switzerland. We conclude that for regional air pollution, fixed-site fine particle levels are valid exposure surrogates. For source-specific exposures, however, fixed-site data are probably not the optimal measure. Still, in air pollution epidemiology, ambient PM 2.5 levels may be more appropriate exposure estimates than total personal PM 2.5 exposure, since the latter reflects a mixture of indoor and outdoor sources.

MEASUREMENT OF LOW LEVEL AIR TOXICS WITH MODIFIED UV DOAS

EPA Science Inventory

To further understand near source impacts, EPA is working to develop open-path optical techniques for spatiotemporal-resolved measurement of air pollutants. Of particular interest is near real time quantification of mobile-source generated CO, Nox and hydrocarbons measured in cl...

Predicting acute aquatic toxicity of structurally diverse chemicals in fish using artificial intelligence approaches.

PubMed

Singh, Kunwar P; Gupta, Shikha; Rai, Premanjali

2013-09-01

The research aims to develop global modeling tools capable of categorizing structurally diverse chemicals in various toxicity classes according to the EEC and European Community directives, and to predict their acute toxicity in fathead minnow using set of selected molecular descriptors. Accordingly, artificial intelligence approach based classification and regression models, such as probabilistic neural networks (PNN), generalized regression neural networks (GRNN), multilayer perceptron neural network (MLPN), radial basis function neural network (RBFN), support vector machines (SVM), gene expression programming (GEP), and decision tree (DT) were constructed using the experimental toxicity data. Diversity and non-linearity in the chemicals' data were tested using the Tanimoto similarity index and Brock-Dechert-Scheinkman statistics. Predictive and generalization abilities of various models constructed here were compared using several statistical parameters. PNN and GRNN models performed relatively better than MLPN, RBFN, SVM, GEP, and DT. Both in two and four category classifications, PNN yielded a considerably high accuracy of classification in training (95.85 percent and 90.07 percent) and validation data (91.30 percent and 86.96 percent), respectively. GRNN rendered a high correlation between the measured and model predicted -log LC50 values both for the training (0.929) and validation (0.910) data and low prediction errors (RMSE) of 0.52 and 0.49 for two sets. Efficiency of the selected PNN and GRNN models in predicting acute toxicity of new chemicals was adequately validated using external datasets of different fish species (fathead minnow, bluegill, trout, and guppy). The PNN and GRNN models showed good predictive and generalization abilities and can be used as tools for predicting toxicities of structurally diverse chemical compounds. Copyright © 2013 Elsevier Inc. All rights reserved.

Air quality assessment for land disposal of industrial wastes

NASA Astrophysics Data System (ADS)

Shen, Thomas T.

1982-07-01

Air pollution from hazardous waste landfills and lagoons is largely unknown. Routine monitoring of toxic air contaminants associated with hazardous waste facilities is difficult and very costly. The method presented in this paper would be useful for air quality assessment in the absence of monitoring data. It may be used as a screening process to examine the question of whether or not volatilization is considered to be significant for a given contaminant and also to evaluate permit applications for new hazardous waste facilities concerning waste volatilization problems.

SMOG-CHAMBER TOXICOLOGY BETTER ESTIMATES THE TRUE TOXIC POTENTIAL OF ATMOSPHERIC MIXTURES

EPA Science Inventory

The chemistry of hazardous air pollutants (HAPs) have been studied for many years, yet little is known about how these chemicals, once interacted with urban atmospheres, affect healthy and susceptible individuals. The toxic potential of these very reactive compounds once they int...

Aerospace toxicology overview: aerial application and cabin air quality.

PubMed

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

A CFD validation roadmap for hypersonic flows

NASA Technical Reports Server (NTRS)

Marvin, Joseph G.

1992-01-01

A roadmap for computational fluid dynamics (CFD) code validation is developed. The elements of the roadmap are consistent with air-breathing vehicle design requirements and related to the important flow path components: forebody, inlet, combustor, and nozzle. Building block and benchmark validation experiments are identified along with their test conditions and measurements. Based on an evaluation criteria, recommendations for an initial CFD validation data base are given and gaps identified where future experiments would provide the needed validation data.

A CFD validation roadmap for hypersonic flows

NASA Technical Reports Server (NTRS)

Marvin, Joseph G.

1993-01-01

A roadmap for computational fluid dynamics (CFD) code validation is developed. The elements of the roadmap are consistent with air-breathing vehicle design requirements and related to the important flow path components: forebody, inlet, combustor, and nozzle. Building block and benchmark validation experiments are identified along with their test conditions and measurements. Based on an evaluation criteria, recommendations for an initial CFD validation data base are given and gaps identified where future experiments would provide the needed validation data.

Embryonic stem cells and the next generation of developmental toxicity testing.

PubMed

Kugler, Josephine; Huhse, Bettina; Tralau, Tewes; Luch, Andreas

2017-08-01

The advent of stem cell technology has seen the establishment of embryonic stem cells (ESCs) as molecular model systems and screening tools. Although ESCs are nowadays widely used in research, regulatory implementation for developmental toxicity testing is pending. Areas Covered: This review evaluates the performance of current ESC, including human (h)ESC testing systems, trying to elucidate their potential for developmental toxicity testing. It shall discuss defining parameters and mechanisms, their relevance and contemplate what can realistically be expected. Crucially this includes the question of how to ascertain the quality of currently employed cell lines and tests based thereon. Finally, the use of hESCs will raise ethical concerns which should be addressed early on. Expert Opinion: While the suitability of (h)ESCs as tools for research and development goes undisputed, any routine use for developmental toxicity testing currently still seems premature. The reasons for this comprise inherent biological deficiencies as well as cell line quality and system validation. Overcoming these issues will require collaboration of scientists, test developers and regulators. Also, validation needs to be made worthwhile for academia. Finally we have to continuously rethink existing strategies, making room for improved testing and innovative approaches.

CHARACTERIZATION OF AIR TOXICS FROM AN OIL-FIRED FIRETUBE BOILER

EPA Science Inventory

Tests were conducted on a commercially available firetube package boiler running on #2 through #6 oils to determine the emissions levels of hazardous air pollutants (HAPs) from the combustion of four fuel oils. Flue gas was sampled to determine levels of volatile and semivolatile...

Validation of Microtox as a first screening tool for waste classification.

PubMed

Weltens, R; Deprez, K; Michiels, L

2014-12-01

The Waste Framework Directive (WFD; 2008/98/EG) describes how waste materials are to be classified as hazardous or not. For complex waste materials chemical analyses are often not conclusive and the WFD provides the possibility to assess the hazardous properties by testing on the waste materials directly. As a methodology WFD refers to the protocols described in the CLP regulation (regulation on Classification, Labeling and Packaging of chemicals) but the toxicity tests on mammals are not acceptable for waste materials. The DISCRISET project was initiated to investigate the suitability of alternative toxicity tests that are already in use in pharmaceutical applications, for the toxicological hazard assessment of complex waste materials. Results indicated that Microtox was a good candidate as a first screening test in a tiered approached hazard assessment. This is now further validated in the present study. The toxic responses measured in Microtox were compared to biological responses in other bioassays for both organic and inorganic fractions of the wastes. Both fractions contribute to the toxic load of waste samples. Results show that the Microtox test is indeed a good and practical screening tool for the organic fraction. A screening threshold (ST) of 5 geq/l as the EC50 value in Microtox is proposed as this ST allows to recognize highly toxic samples in the screening test. The data presented here show that the Microtox toxicity response at this ST is not only predictive for acute toxicity in other organisms but also for sub lethal toxic effects of the organic fraction. This limit value has to be further validated. For the inorganic fraction no specific biotest can be recommended as a screening test, but the use of direct toxicity assessment is also preferable for this fraction as metal speciation is an important issue to define the toxic load of elutriate fractions. A battery of 3 tests (Microtox, Daphnia and Algae) for direct toxicity assessment of this

Potential Air Toxics Hot Spots in Truck Terminals and Cabs

PubMed Central

Smith, Thomas J.; Davis, Mary E.; Hart, Jaime E.; Blicharz, Andrew; Laden, Francine; Garshick, Eric

2016-01-01

INTRODUCTION Hot spots are areas where concentrations of one or more air toxics — organic vapors or particulate matter (PM) — are expected to be elevated. The U.S. Environmental Protection Agency’s (EPA*) screening values for air toxics were used in our definition of hot spots. According to the EPA, a screening value “is used to indicate a concentration of a chemical in the air to which a person could be continually exposed for a lifetime … and which would be unlikely to result in a deleterious effect (either cancer or noncancer health effects)” (U.S. EPA 2006). Our characterization of volatile organic compounds (VOCs; namely 18 hydrocarbons, methyl tert-butyl ether [MTBE], acetone, and aldehydes) was added onto our ongoing National Cancer Institute–funded study of lung cancer and particulate pollutant concentrations (PM with an aerodynamic diameter ≤ 2.5 µm [PM2.5], elemental carbon [EC], and organic carbon [OC]) and source apportionment of the U.S. trucking industry. We focused on three possible hot spots within the trucking terminals: upwind background areas affected by nearby industrial parks; downwind areas affected by upwind and terminal sources; and the loading docks and mechanic shops within terminal as well as the interior of cabs of trucks being driven on city, suburban, and rural streets and on highways. METHODS In Phase 1 of our study, 15 truck terminals across the United States were each visited for five consecutive days. During these site visits, sorbent tubes were used to collect 12-hour integrated samples of hydrocarbons and aldehydes from upwind and downwind fence-line locations as well as inside truck cabs. Meteorologic data and extensive site information were collected with each sample. In Phase 2, repeat visits to six terminals were conducted to test the stability of concentrations across time and judge the representativeness of our previous measurements. During the repeat site visits, the sampling procedure was expanded to