Institution
United States Environmental Protection Agency
Government•Washington D.C., District of Columbia, United States•
About: United States Environmental Protection Agency is a government organization based out in Washington D.C., District of Columbia, United States. It is known for research contribution in the topics: Population & Environmental exposure. The organization has 13873 authors who have published 26902 publications receiving 1191729 citations. The organization is also known as: EPA & Environmental Protection Agency.
Papers published on a yearly basis
Papers
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TL;DR: In this article, the concentrations of ozone, nitrogen oxides, and nonmethane hydrocarbons measured near the surface in a variety of urban, suburban, rural, and remote locations are analyzed and compared in order to elucidate the relationships between ozone, its photochemical precursors, and the sources of these precursor.
Abstract: The concentrations of ozone, nitrogen oxides, and nonmethane hydrocarbons measured near the surface in a variety of urban, suburban, rural, and remote locations are analyzed and compared in order to elucidate the relationships between ozone, its photochemical precursors, and the sources of these precursors. While a large gradient is found among remote, rural, and urban/suburban nitrogen oxide concentrations, the total hydrocarbon reactivity in all continental locations is found to be comparable. Apportionment of the observed hydrocarbon species to mobile and stationary anthropogenic sources and biogenic sources suggests that present-day emission inventories for the United States underestimate the size of mobile emissions. The analysis also suggests a significant role for biogenic hydrocarbon emissions in many urban/suburban locations and a dominant role for these sources in rural areas of the eastern United States. As one moves from remote locations to rural locations and then from rural to urban/suburban locations, ozone and nitrogen oxide concentrations tend to increase in a consistent manner while total hydrocarbon reactivity does not.
724 citations
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TL;DR: Although drinking-water disinfection byproducts (DBPs) have been studied for the last 30 years, significant, new concerns have arisen as discussed by the authors, including adverse reproductive and developmental effects recently observed in human populations, concerns that the types of cancer observed in laboratory animals (for regulated DBPs) do not correlate with the cancers observed in humans (indicating that other DBPs may be important), and concerns arising from human-exposure studies that show that other routes besides ingestion (i.e., inhalation and dermal adsorption) are also significant sources of DBP
Abstract: Although drinking-water disinfection by-products (DBPs) have been studied for the last 30 years, significant, new concerns have arisen. These concerns include adverse reproductive and developmental effects recently observed in human populations, concerns that the types of cancer observed in laboratory animals (for regulated DBPs) do not correlate with the cancers observed in human populations (indicating that other DBPs may be important), and concerns arising from human-exposure studies that show that other routes besides ingestion (i.e., inhalation and dermal adsorption) are also significant sources of DBP exposures. In addition, many drinking-water utilities are changing their primary disinfectant from chlorine to alternative disinfectants (e.g., ozone, chlorine dioxide, and chloramines), which generally reduce regulated trihalomethane and haloacetic acid levels, but can increase the levels of other potentially toxicologically important DBPs. For example, results of a new US Nationwide DBP Occurrence Study (discussed in this review) demonstrated that bromo-trihalonitromethanes, iodo-trihalomethanes, dihaloaldehydes, MX (3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone), and brominated forms of MX were formed at higher levels when alternative disinfectants were used to treat drinking water. Specific DBPs of emerging toxicological interest include brominated and iodinated compounds — including bromonitromethanes, iodo-trihalomethanes, iodo-acids, and brominated forms of MX — as well as nitrosodimethylamine (NDMA). In addition to concerns about DBPs, there are also new concerns about the presence of pharmaceuticals, organotins, methyl-tert-butyl ether (MTBE), perchlorate, and algal toxins in drinking water. This article will discuss these drinking-water contaminants of emerging concern and the analytical methods currently being used for their determination.
721 citations
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TL;DR: The antibacterial property of bulk silver is expected to be carried over and perhaps enhanced, to silver nanoparticles, and when one examines the environmental issues associated with the manufacture and use of silver nanoparticle-based products, the antibacterial effects should always be taken into account.
718 citations
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National Oceanic and Atmospheric Administration1, University of Washington2, University of Maryland Center for Environmental Science3, University of Kansas4, United States Geological Survey5, University of California, San Diego6, University of Miami7, Cornell University8, University of New Orleans9, Old Dominion University10, United States Environmental Protection Agency11
TL;DR: A summary of the coastal and marine resources sector review of potential impacts on shorelines, estuaries, coastal wetlands, coral reefs, and ocean margin ecosystems can be found in this article.
Abstract: Increases in concentrations of greenhouse gases projected for the 21st century are expected to lead to increased mean global air and ocean temperatures. The National Assessment of Potential Consequences of Climate Variability and Change (NAST 2001) was based on a series of regional and sector assessments. This paper is a summary of the coastal and marine resources sector review of potential impacts on shorelines, estuaries, coastal wetlands, coral reefs, and ocean margin ecosystems. The assessment considered the impacts of several key drivers of climate change: sea level change; alterations in precipitation patterns and subsequent delivery of freshwater, nutrients, and sediment; increased ocean temperature; alterations in circulation patterns; changes in frequency and intensity of coastal storms; and increased levels of atmospheric CO2. Increasing rates of sea-level rise and intensity and frequency of coastal storms and hurricanes over the next decades will increase threats to shorelines, wetlands, and coastal development. Estuarine productivity will change in response to alteration in the timing and amount of freshwater, nutrients, and sediment delivery. Higher water temperatures and changes in freshwater delivery will alter estuarine stratification, residence time, and eutrophication. Increased ocean temperatures are expected to increase coral bleaching and higher CO2 levels may reduce coral calcification, making it more difficult for corals to recover from other disturbances, and inhibiting poleward shifts. Ocean warming is expected to cause poleward shifts in the ranges of many other organisms, including commercial species, and these shifts may have secondary effects on their predators and prey. Although these potential impacts of climate change and variability will vary from system to system, it is important to recognize that they will be superimposed
713 citations
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TL;DR: This review marginalizes various studies conducted so far about EPS nature-production-recovery, properties, environmental applications and moreover, critically examines future research needs and advanced application prospective of the EPS.
709 citations
Authors
Showing all 13926 results
Name | H-index | Papers | Citations |
---|---|---|---|
Joel Schwartz | 183 | 1149 | 109985 |
Timothy A. Springer | 167 | 669 | 122421 |
Chien-Jen Chen | 128 | 655 | 66360 |
Matthew W. Gillman | 126 | 529 | 55835 |
J. D. Hansen | 122 | 975 | 76198 |
Dionysios D. Dionysiou | 116 | 675 | 48449 |
John P. Giesy | 114 | 1162 | 62790 |
Douglas W. Dockery | 105 | 244 | 57461 |
Charles P. Gerba | 102 | 692 | 35871 |
David A. Savitz | 99 | 572 | 32947 |
Stephen Polasky | 99 | 354 | 59148 |
Judith C. Chow | 96 | 427 | 32632 |
Diane R. Gold | 95 | 443 | 30717 |
Scott L. Zeger | 95 | 377 | 78179 |
Rajender S. Varma | 95 | 672 | 37083 |