Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Environmental Protection Agency”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25Linked to original sources
PubMed2006

Key scientific issues in the health risk assessment of trichloroethylene.

Trichloroethylene (TCE) is a common environmental contaminant at hazardous waste sites and in ambient and indoor air. Assessing the human health risks of TCE is challenging because of its inherently complex metabolism and toxicity and the widely varying perspectives on a number of critical scientific issues. Because of this complexity, the U.S. Environmental Protection Agency (EPA) drew upon scientific input and expertise from a wide range of groups and individuals in developing its 2001 draft health risk assessment of TCE. This scientific outreach, which was aimed at engaging a diversity of perspectives rather than developing consensus, culminated in 2000 with 16 state-of-the-science articles published together as an Environmental Health Perspectives supplement. Since that time, a substantial amount of new scientific research has been published that is relevant to assessing TCE health risks. Moreover, a number of difficult or controversial scientific issues remain unresolved and are the subject of a scientific consultation with the National Academy of Sciences coordinated by the White House Office of Science and Technology Policy and co-sponsored by a number of federal agencies, including the U.S. EPA. The articles included in this mini-monograph provide a scientific update on the most prominent of these issues: the pharmacokinetics of TCE and its metabolites, mode(s) of action and effects of TCE metabolites, the role of peroxisome proliferator-activated receptor in TCE toxicity, and TCE cancer epidemiology.

Dose-Response Relationship, Drug↗
PubMed2006

Evaluation of repeated measurements of radon-222 concentrations in well water sampled from bedrock aquifers of the Piedmont near Richmond, Virginia, USA: effects of lithology and well characteristics.

Radon (222Rn) concentrations in 26 ground water wells of two distinct lithologies in the Piedmont of Virginia were measured to assess variation in ground water radon concentrations (GWRC), to evaluate differences in concentrations related to well characteristics, lithology, and spatial distributions, and to assess the feasibility of predicting GWRC. Wells were sampled in accordance with American Public Health Association Method 7500 Rn-B, with modifications to include a well shaft profile analysis that determined the minimum purge time sufficient to remove the equivalent of one column of water from each well. Statistically significant differences in GWRC were found in the Trssu (1482 +/- 1711 pCi/L) and Mpg (7750 +/- 5188 pCi/L) lithologies, however, no significant differences were found among GWRC at each well over time. Using multiple regression, 86% of the variability (R2) in the GWRC was explained by the lithology, latitudinal class, and water table elevation of the wells. The GWRC in a majority of the wells studied exceed US Environmental Protection Agency designated maximum contaminant level and AMCL. Results support modifications to sampling procedures and indicate that, in previous studies, variations in GWRC concentrations over time may have been due in part to differences in sampling procedures and not in source water.

Carcinogens, Environmental↗
PubMed2004

Perspectives on the nature and definition of ecological regions.

Among environmental managers, recognition of the importance of integrating management activities across agencies and programs that have different responsibilities for the same geographic areas has created an awareness of the need for a common hierarchical framework of ecological regions (ecoregions) to implement the strategy. Responding to this need in the United States, nine federal agencies have signed a memorandum of understanding on the subject of developing a common framework of ecoregions. However, considerable disagreement over how to define ecoregions and confusion over the strengths and limitations of existing frameworks stand in the way of achieving this goal. This paper presents some perspectives on the nature and definition of ecoregions related to this confusion and provides a brief overview of the weight of evidence approach to mapping ecoregions, using an example initiated by the US Environmental Protection Agency. To effectively implement ecosystem assessment, management, and research at local, regional, and national levels, research is needed to increase our understanding of ecoregions. We must find ways to illustrate the nature of ecoregion boundaries and the variability of characteristics within ecoregions as they relate to management issues. Research must also be conducted on comparing existing frameworks and developing indices of ecological integrity to effectively evaluate their usefulness.

Conservation of Natural Resources↗
PubMed1999

Chloroform: An EPA test case.

In March 1998, the U.S. Environmental Protection Agency (EPA) published a proposal to raise the drinking water maximum contaminant level goal (MCLG) for chloroform, a suspected human carcinogen, from zero to 300 parts per billion. The proposal marked a departure from the agency's traditional reliance on linear dose-response models in performing risk assessment, and reflected the new thinking contained in the 1996 draft update to the agency's cancer risk assessment guidelines. The updated guidelines emphasize mechanisms of action and descriptions of the conditions under which carcinogenic hazards are likely to be expressed.

Animals↗
PubMed2006

Keys to effective third-party process safety audits.

The Occupational Safety and Health Administration's (OSHA's) Process Safety Management (PSM) regulation was promulgated in 1992. The U.S. Environmental Protection Agency's (EPA's) corresponding Risk Management Program (RMP) rule followed in 1996. Both programs include requirements for triennial compliance audits. Effective compliance audits are critical in identifying program weaknesses and ensuring the safety of facility personnel and the surrounding public. Large companies with corporate and facility health, safety, and environmental groups typically have the resources and experience to conduct audits internally, either through a corporate audit team or the sharing of personnel between multiple facilities. Small to medium sized businesses frequently do not have the expertise or the resources to perform compliance audits, and rely on third-party consultants to provide these services. This paper will discuss the observations of the authors in performing audits and working with PSM/RMP programs across a number of market sectors (e.g. chemical, petrochemical, pharmaceutical, food and beverage, water treatment), including effective practices, hurdles to successful implementation and execution of programs, and typical program shortcomings. The paper will also discuss steps to improve the audit process and increase effectiveness whether performed by a third party or internally.

Environmental Health↗
PubMed1993

Superfund and one community program.

The U.S. Environmental Protection Agency--Region II conducted a pilot program in risk communication and notification of hazardous waste information at a Superfund site in Toms River, New Jersey. The program was designed to assess the levels of awareness and concern among local citizens and to provide accurate information about health risks associated with potential exposure to environmental contaminants. The purpose of this program was to develop linkages among the community; local, state, and federal governments; industry; health professionals; and educators in dealing with environmental problems. A Community Leaders Network was formed and became actively involved in the program. Following a community needs assessment for risk information, a series of fact sheets was developed, pretested, disseminated, and evaluated. The analysis of the program highlights the important lesson of being able to respond to the specific changing dynamics of the community and offers guidelines useful for risk communication in many communities.

Chemical Industry↗
PubMed2006

The benefits and costs of reducing emissions from the electricity sector.

Recent federal policy proposals to reduce emissions of sulfur dioxide (SO(2)), nitrogen oxides (NO(x)), and mercury from the US electricity sector promise important improvements in air quality and reductions in acid deposition. The cost of achieving these reductions depends on the form and stringency of the regulation. In this research, we analyze the economic benefits and costs of the US Environmental Protection Agency's (EPA's) Clean Air Interstate Rule (CAIR) as characterized in the supplemental rule proposed in June 2004, and the Clean Air Mercury Rule (CAMR) as proposed in February 2004. The assessment integrates a model of the electricity sector, two models of atmospheric transport of air pollutants, and a model of environmental and public health endpoints affected by pollution. We model explicitly the emissions of SO(2), NO(x), mercury and carbon dioxide (CO(2)) and the effects of changes in emissions of SO(2) and NO(x) on environmental and public health. The manner in which mercury emissions are regulated will have important implications not only for the cost of the regulation, but also for emission levels for SO(2) and NO(x) and where those emissions are located. We find the economic benefits of CAIR and CAMR are far greater than the costs. Recent estimates of benefits of reductions in mercury and acidification indicate that our model captures the lion's share of quantifiable benefits. We also find that the EPA would have been justified on economic grounds in pursuing additional SO(2) emissions reductions beyond the requirements of CAIR.

Air Pollution↗
PubMed2002

Leaching of trifluralin, metolachlor, and metribuzin in a clay loam soil of Louisiana.

Trifluralin[2,6-dinitro-N,N-dipropyl-4-(trifluormethyl)benzenamine], metolachlor[2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide], and metribuzin[4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)one] were applied in field plots located on a Commerce clay loam soil near Baton Rouge, Louisiana at the rate of 1683 g/ha, 2759 g/ha and 609 g/ha, respectively. The half-lives of trifluralin, metolachlor, and metribuzin in the top 0-15 cm soil depth were found to be 54.7 days, 35.8 days and 29.8 days, respectively. The proportion of trifluralin, metolachlor, and metribuzin in the top 0-15 cm soil depth was 94.7%, 86.6%, and 75.4%, respectively of that found in the top 0-60 cm soil depth 30 days after application. Trifluralin concentrations were within a range of 0.026 ng/mL to 0.058 ng/mL in 1 m deep well water, and between 0.007 ng/mL and 0.039 ng/mL in 2 m deep well water over a 62 day period after application. Metolachlor concentrations in the 1 m and 2 m wells ranged from 3.62 ng/mL to 82.32 ng/mL and 8.44 ng/mL to 15.53 ng/mL, respectively. Whereas metribuzin concentrations in the 1 m and 2 m wells ranged from 0.70 ng/mL to 27.75 ng/mL and 1.71 ng/mL to 3.83 ng/mL, respectively. Accordingly, trifluralin was found to be strongly adsorbed on the soil and showed negligible leaching. Although metolachlor and metribuzin were also both readily adsorbed on the soil, their leaching potential was high. As a result, in the clay loam soil studied, metribuzin concentration in groundwater with shallow aquifers is likely to exceed the 10 mg/L US Environmental Protection Agency (EPA) advisory level for drinking water early in the application season, whereas trifluralin and metolachlor concentrations are expected to remain substantially lower than their respective 2 ng/mL and 175 ng/mL EPA advisory levels.

Acetamides↗
PubMed1991

Organizational components and structural features of EPA's new Human Exposure Research Program.

Modern technology has brought about a dramatic increase in the production and consumption of man-made chemicals and in their resulting emissions. It is clear that these emissions and their by-products will likely affect our environment and have a health impact on the population exposed to them. Knowledge of exposure is required to document the impact of these emissions on human health. However, measuring, interpreting, and characterizing human exposures are extraordinarily complex processes because exposures may occur by multiple routes, multiple sources, and they are subject to a wide range of temporal, spatial, and source variations often from both anthropogenic and non-anthropogenic sources. The Environmental Protection Agency's approach to exposure research has often been insufficient to understand and mitigate these complex real-word exposures. For example, we do not know the population exposure distributions of most pollutants and the relative contributions of sources to these distributions. Without this knowledge as input into EPA's risk management process, EPA's may not be making the most effective environmental management decisions for reducing human health risks. The Human Exposure Research Program is a direct response to this need to understand how and to what extent humans are exposed to environmental pollutants.

Databases, Factual↗
PubMed1986

EDB: a case study in communicating risk.

This is a report on the Environmental Protection Agency's (EPA's) efforts to communicate with the public about the risks of ethylene dibromide (EDB), what the agency said it was doing about these risks and what information the public actually received through television and newspapers. Although special in many ways, the EDB case illustrates the problems that regulatory agencies have when they must take regulatory action and assure the public that the risks in question are being dealt with adequately. It also illustrates issues that the press faces. Above all, it illustrates the barriers to communication presented by the different perspectives of regulatory agencies and individuals and the types of information they each are most interested in.

Carcinogens↗
PubMed1998

Intercomparison of radon and decay product measurements in an underground mine and EPA Radon Laboratory: a study organized by the IAEA International Radon Metrology Programme. International Atomic Energy Agency.

The International Atomic Energy Agency (IAEA) in Vienna and the European Union (EU) in Bruxelles formed the "International Radon Metrology Programme" (IRMP, scientific secretary: F. Steinhäusler, University of Salzburg, Austria). The IRMP is designed to assess and foster the improvement of radon and decay product measurements that are made around the world. Within the framework of the IRMP, the U.S. Environmental Protection Agency Radiation and Indoor Environments National Laboratory (EPA) in Las Vegas, Nevada, organized jointly with the U.S. Bureau of Mines an international intercomparison exercise at a former uranium mine (Twilight Mine, Colorado) and the EPA Radon Laboratory. The main objective of this exercise was to compare radon and radon decay product instruments under both well-controlled as well as widely fluctuating exposure conditions. The laboratory exposures occurred under relatively steady radon and decay product conditions, with a moderate equilibrium ratio, while the conditions in the mine fluctuated greatly and the equilibrium ratio was low. An additional purpose of the exercise was to provide a forum for manufacturers and measurement organizations worldwide to exchange information and plan improvements in their operations and calibration programs. Altogether 19 organizations from seven countries intercomparing 32 different radon and radon decay product instruments participated in this exercise. This paper summarizes the results from the analysis of the experimental data obtained in the Bureau of Mines Twilight Mine in July of 1994, as well as the results from the EPA Radon laboratory in August of 1994.

Calibration↗
PubMed1997

Evaluation of the Ultraviolet Index: media reactions and public response.

BACKGROUND: In response to the increasing rate of skin cancer, particularly melanoma in the United States, the Environmental Protection Agency, the National Weather Service, the Centers for Disease Control and Prevention, National Association of Physicians for the Environment, and the American Academy of Dermatology, developed the Ultraviolet Index (UVI) to inform the public of the strength of the sun's rays and advise on methods for sun protection. OBJECTIVE: Our purpose was to evaluate the extent to which television stations and newspapers reported the UVI and assess the public's response to it. METHODS: To evaluate the effect of this effort, we surveyed television weather forecasters at 185 stations and examined weather pages in 54 newspapers in 58 cities that received the UVI reports. We also conducted a population probability telephone survey of 700 white adults (18 years of age and older) in these 58 cities. RESULTS: Seventy-one percent of the 169 stations that provided survey data for both 1994 and 1995 broadcast the UVI; 61% of newspapers reported the UVI. Nearly 64% of the 700 respondents (n = 445) had heard of the UVI. Of these respondents, 38% (n = 170) stated that they or their family changed their sun protection practices as a result of the UVI. CONCLUSION: The majority of television weather forecasters and newspapers reported the UVI. Most of the public was aware of the UVI, causing some to change sun protection practices. Further evaluation is required to maximize the effect of the UVI on sun protection practices.

Adult↗
PubMed1997

Drosophila melanogaster, Vicia faba and Arabidopsis thaliana short-term bioassays in genotoxicity evaluation of air and soil samples from sites surrounding two industrial factories in the Czech Republic.

The Somatic Mutation and Recombination Test (SMART) in wing cells of Drosophila melanogaster, the Vicia faba cytogenetic tests-Sister Chromatid Exchange (SCE) and Micronucleus Test (MN), and the Müller test for gametic mutations in Arabidopsis thaliana were used for genotoxicity testing of environmental samples of pollutants from the surroundings of LACHEMA chemical factory (Brno, Czech Republic) and DEZA factory in Valasské Mezirící (Moravia, Czech Republic). Tested soil and air samples were taken from the near vicinity of both factories. The surroundings of both sites are heavy loaded by exhalation of chemicals from the factories. Chemical analyses of the 16 Polycyclic Aromatic Hydrocarbons (PAHs) according to the United States Environmental Protection Agency (US EPA) list of priority pollutants and heavy metals were performed in both soil and air samples. The Drosophila wing spot test was positive in 70.6% of the tested samples, the Vicia sister chromatid exchange test in 62.5%, and the Arabidopsis Müller test in 58.9%. The micronucleus Vicia faba test was quite insensitive in tested environmental samples. The concordance between SMART and SCE was 62.5%, between SMART and Müller test 76.5%, and between Müller test and SCE 100%. Total concordance of these three tests was 79.7%. Müller test for gametic mutation in Arabidopsis thaliana and cytogenetic SCE test in Vicia faba seem to be quite sensitive and convenient plant bioassays for assessing the mutagenic potential of environmental agents, when compared to the SMART test in Drosophila melanogaster.

Air Pollutants, Occupational↗
PubMed2005

Potential interference bias in ozone standard compliance monitoring.

The U.S. Environmental Protection Agency has established a federal reference method (FRM) for ozone (O3) and allowed for designation of federal equivalent methods (FEMs). However, the ethylene-chemiluminescence FRM for O3 has been replaced by the UV photometric FEM by most state and local monitoring agencies because of its relative ease of operation. Accumulating evidence indicates that the FEM is prone to bias under the hot, humid, and stagnant conditions conducive to high O3 formation. This bias may lead to overreporting hourly O3 concentrations by as much as 20-40 ppb. Measurement bias is caused by contamination of the O3 scrubber, a problem that is not detected by dry air calibration. An adequate wet test has not been codified, although a procedure has been proposed for agency consideration. This paper includes documentation of laboratory tests quantifying specific interferant responses, collocated ambient FRM/FEM monitoring results, and smog chamber comparisons of the FRM and FEMs with alternative scrubber designs. As the numbers of reports on monitor interferences have grown, interested parties have called for agency recognition and correction of these biases.

Air Pollutants, Occupational↗
PubMed1991

Human exposure assessment and public health.

The scientific basis for public and private actions to ameliorate environmental health risks is the suspected or verified link between environmental exposures and human health effects. Exposure information is a key parameter, along with data on dose-response relationships, in determining which environmental health risks are unacceptable. Moreover, human exposures are the standard by which we judge the success of measures to prevent or reduce those risks that are deemed unacceptable. The concept of "total human exposure" has gained credence as a useful and viable framework by which to assess environmental exposures. It places exposures in the context of the continuum beginning with pollutant emissions to the environment and ending with human health consequences. The advent of biologic exposure markers, as well as effects and susceptibility markers, promises the opportunity to more accurately characterize total human exposures for environmental contaminants; thereby enhancing the quality of health risk assessments. The U.S. Environmental Protection Agency plays a significant role in the validation, application, and interpretation of biologic markers, with a lesser but important role in their development. Because the Agency is involved in virtually all phases of the biologic markers issue, EPA scientists have identified important research questions and developed plans to address those questions over the next several years. The EPA is positioned to promote the science necessary to bring biologic markers to bear on environmental issues and to interpret the results for risk assessment, risk management, and risk communication.

Biomarkers↗
PubMed1995

Radon exposure: a review of the public health risk in Anne Arundel County, Maryland.

Long-term exposure to indoor radon may lead to an increased lifetime risk of lung cancer. Because millions of U.S. residential homes may have elevated radon levels, indoor radon exposure may pose a substantial public health threat. In Anne Arundel County (Maryland), a county-wide residential radon survey indicated that 82% of all residential radon readings in the survey were below Environmental Protection Agency remediation guidelines. Of the elevated indoor measurements, however, 94.4% were distributed in the southern portion of the county. These results are consistent with data compiled by the EPA and the U.S. Geologic Survey. Continued residential radon testing should be encouraged, especially in areas with elevated readings.

Air Pollution, Indoor↗
PubMed2003

Beverages: bottled water. Direct final rule.

The Food and Drug Administration (FDA) is amending its bottled water quality standard regulations by establishing an allowable level for the contaminant uranium. As a consequence, bottled water manufacturers are required to monitor their finished bottled water products for uranium at least once each year under the current good manufacturing practice (CGMP) regulations for bottled water. Bottled water manufacturers are also required to monitor their source water for uranium as often as necessary, but at least once every 4 years unless they meet the criteria for the source water monitoring exemptions under the CGMP regulations. FDA will retain the existing allowable levels for combined radium-226/-228, gross alpha particle radioactivity, and beta particle and photon radioactivity. This direct final rule will ensure that the minimum quality of bottled water, as affected by uranium, combined radium-226/-228, gross alpha particle radioactivity, and beta particle and photon radioactivity, remains comparable with the quality of public drinking water that meets the Environmental Protection Agency's (EPA's) standards. FDA is issuing a direct final rule for this action because the agency expects that there will be no significant adverse comment on this rule. Elsewhere in this issue of the Federal Register, FDA is publishing a companion proposed, rule under the agency's usual procedure for notice-and-comment rulemaking, to provide a procedural framework to finalize the rule in the event the agency receives any significant adverse comments and withdraws this direct final rule. The companion proposed rule and direct final rule are substantively identical.

Consumer Product Safety↗
PubMed2001

An overview of human exposure modeling activities at the USEPA's National Exposure Research Laboratory.

The computational modeling of human exposure to environmental pollutants is one of the primary activities of the US Environmental Protection Agency (USEPA)s National Exposure Research Laboratory (NERL). Assessment of human exposures is a critical part of the overall risk assessment paradigm. In exposure assessment, we analyze the source-to-dose sequence of processes, in which pollutants are released from sources into the environment, where they may move through multiple environmental media, and to human receptors via multiple pathways. Exposure occurs at the environment-human interface, where pollutants are contacted in the course of human activities. Exposure may result in a dose, by which chemicals enter the body through multiple portals of entry, primarily inhalation, ingestion, and dermal absorption. Within the body, absorbed pollutants are distributed to, metabolized within, and eliminated from various organs and tissues, where they may cause toxicologic responses or adverse health effects. The NERL's modeling efforts are directed at improving our understanding of this sequence of processes, by characterizing the various factors influencing exposures and dose, and their associated variabilities and uncertainties. Modeling at the NERL is one of three essential programmatic elements, along with measurements and methods development. These are pursued interactively to advance our understanding of exposure-related processes. Exposure models are developed and run using the best currently available measurement data to simulate and predict population exposure and dose distributions, and to identify the most important factors and their variabilities and uncertainties. This knowledge is then used to guide the development of improved methods and measurements needed to obtain better data to improve the assessment and reduce critical uncertainties. These models and measurement results are tools that can be used in risk assessments and in risk management decisions in order to reduce harmful exposures. Current areas of the NERL's exposure modeling emphasis include: Pollutant concentrations in ambient (outdoor) air using the Third Generation Air Quality Modeling System's Community Multiscale Air Quality model (Models-3/CMAQ); Air flow and pollutant concentrations at local and microenvironmental scales using computational fluid dynamics (CFD); Human inhalation exposure to airborne particulate matter, air toxics, and multipathway exposure to pesticides, using the Stochastic Human Exposure and Dose Simulation (SHEDS) model; Human and ecological exposure and risk assessments of hazardous waste sites using Framework for Risk Analysis in Multimedia Environmental Systems--Multimedia, Multipathway, Multireceptor Risk Assessment (FRAMES-3MRA), one of many software programs available from the NERL's Center for Exposure Assessment Modeling (CEAM); Physiologically based pharmacokinetic (PBPK) modeling of pesticides and volatile organic compounds (VOCs) in the Exposure-Related Dose-Estimating Model (ERDEM). A brief historical overview of the NERL's evolution of human exposure models is presented, with examples of the present state-of-the-science represented by SHEDS and FRAMES-3MRA.

Air Pollutants↗