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591.
Douglas A. Wolfe K. John Scott John R. Clayton Jr. John Lunz James R. Payne Timothy A. Thompson 《Chemistry and Ecology》1995,10(1):137-156
Standardized tests were applied to aromatic and polar fractions of sediment extracts to determine whether polar constituents or oxidative degradation products contributed significantly to the toxicity of sediments oiled by the Exxon Valdez spill. Intertidal sediment and pore-water samples were collected in September 1990 from two heavily oiled sites and an unoiled site in Prince William Sound (PWS). Methylene chloride extracts from these samples were fractionated by liquid chromatography into aliphatic, aromatic and polar fractions, and the aromatic and polar fractions were tested for toxicity using the MicrotoxR test, bivalve larval mortality and development (Mytilus); several measures of genotoxicity in Mytilus, including SOS ChromotestR, anaphase aberrations and sister chromatid exchange; and survival, anaphase aberrations and teratogenicity in coho salmon (Onchorhynchus kisutch). MicrotoxR and SOS ChromotestR protocols were applied in a screening mode to all samples, whereas other tests were applied only to selected fractions from two sites. Samples from Bay of Isles (oiled) were consistently more toxic (usually only 2 to 5-fold) than the Mooselips Bay (unoiled) samples, which gave very low responses in all tests. for both sites, however, responses to polar and aromatic fractions were about the same in most tests, suggesting that while the overall toxicity of the oil was low in these samples, at least part of that toxicity was derived from polar constituents. Compared to the parent hydrocarbons, polar oxidation products partition preferentially into pore-water and are more rapidly diluted and dispersed in the water column. These results suggest that polar oxidation products of petroleum hydrocarbons pose little risk to marine organisms, except possibly for infauna continuously exposed to pore-water in heavily oiled sediments. Independent surveys showed that sediment toxicity in PWS declined during 1989-1991 to near background levels, in accord with previous understanding of oil weathering and toxicity. 相似文献
592.
This report was by John F. Disinger, Professor of Natural Resources, and Jennifer L. Tomsen, Graduate Teaching Associate in Natural Resources, The Ohio State University, Columbus, Ohio, 43210–1085, USA. 相似文献
593.
594.
John Atle Kålås Thor Harald Ringsby Syverin Lierhagen 《Environmental monitoring and assessment》1995,36(3):251-270
This paper reports the concentrations of metals (Al, As, Cd, Cr, Cu, Hg, Ni, Pb, and/or Zn) and selenium (Se) in kidney and/or liver samples from capercaillie (Tetrao urogallus), willow ptarmigan (Lagopus lagopus), hares (Lepus timidus), common shrews (Sorex araneus) and grey-sided voles (Clethrionomus rufocanus) from the Norwegian areas most heavily contaminated by pollutants from the Russian smelters on the Kola peninsula. In addition to comparing areas that differed in expected pollution rate within Sør-Varanger, comparisons are drawn with reference data from other parts of Norway. The relatively highest levels of metals were found for Cu and Ni in the sub-area most heavily exposed to pollution from the smelters. Also the highest Cr concentrations were found in the areas closest to the smelters. In this study, there is evidence for a direct link between increased metal concentrations in wild animals and pollution from the Russian smelters for Cu and Ni and to some extent for Cr. relatively high concentration of Hg and slight increases in Pb are also documented, but regional differences within Sør-Varanger indicate no direct relationship to the Russian smelters. No samples showed concentrations of any of the analysed metals in excess of the limits where negative effects on animals can be measured. 相似文献
595.
John D. Morgan 《Resources Policy》1980,6(1):33-43
In 1978 the USA used non-fuel processed mineral materials valued at over $200 billion (109). Non-fuel mineral imports caused a trade imbalance of $8 billion. Imports supplied more than half of US supplies of 20 important minerals. The US stockpile of strategic materials is valued at over $11 billion. While world reserves of most minerals are now deemed adequate until 2000, demand for high temperature and special property materials requires careful monitoring and anticipation of disruptions in vulnerable sources. 相似文献
596.
597.
The results of more than 1 yr of air monitoring inside and outside of five homes in each of two communities are presented for SO2, NO2, mass respirable particles, SO4, Al, Br, Cl, Mn, Na, and V. Outdoor measurements across the home site in each city are consistent with proximity to outdoor sources. Looking across indoor residential sites in each city, the home appears to alter outdoor concentrations in several ways. Indoor level of SO2, SO4, Mn, and V are lower than those measured outdoors. These constituents are thought generally to result from outdoor sources. The other constituents studied are at times found in excess within homes. In some cases the source or sources of excess concentration of a particular constituent could be identified; often, however, the source of excess indoor concentration could not be identified. 相似文献
598.
Bioassays can provide meaningful information about the relative toxicity of remediated soil samples, revealing the unwelcome toxic side effects produced by some cleanup projects. Section 121 of CERCLA's 1986 amendments calls for hazardous waste site remediations to permanently and significantly reduce the volume, toxicity, and mobility of hazardous substances, pollutants, and contaminants. Traditional engineering technology has focused on reducing volume and mobility, assuming that such reduction would lead to reductions in toxicity. Environmental scientists have argued, however, that such reductions are not always the result, but lack of consensus on how hazardous waste mixtures should be measured toxicologically has slowed development of integrated assessments. The aquatic and terrestrial bioassays discussed in this article are evaluated for various chemicals, mixtures of chemicals, and actual waste site chemical mixtures at a Superfund mobility reduction project in Kent, Washington. Results suggest that although remediation accomplished the primary objective of reducing mobility, it also introduced toxic effects. These tradeoffs must be viewed holistically when the ultimate performance of cleanup measures is judged. 相似文献
599.
Fred D. Hall John M. Bruck Diane N. Albrinck Robert A. Olexsey 《Environment international》1981,6(1-6)
The recovery of energy from the combustion of municipal solid wastes is becoming an attractive alternative as landfill space becomes scarce and the availability of fossil fuels decreases. Particulate emissions from “waste-as-fuel” processes, however, may differ significantly in chemical and physical properties from particulate emissions produced by firing only coal. Such differences can affect the design and operation of air pollution control equipment. Presented in this paper are the results of a 2-month test program at Ames, Iowa, with a mobile electrostatic precipitator (ESP) and a mobile scrubber supplied by the U.S. Environmental Protection Agency (EPA), Industrial Environmental Research Laboratory (IERL), Research Triangle Park. PEDCo Environmental, Inc., and Acurex Corporation jointly conducted the test program to examine the effect of burning refuse-derived fuel (RDF) on particulate and heavy metal control efficiencies. The mobile ESP was used only as a primary control device, whereas the mobile scrubber was tested both upstream and downstream of the existing full-scale ESP. This paper also presents a status report on a PEDCo test program with a pilot fabric filter at Ames. 相似文献
600.
As a guide to the possible effects of a CO2-induced warming on the cryosphere, we review the effects of three warm periods in the past, and out theoretical understanding of fluctuations in mountain glaciers, the Greenland and Antarctic ice sheets, ground ice, sea ice and seasonal snow cover. Between 1890 and 1940 A.D. the glaciated area in Switzerland was reduced by over 25%. In the Hypsithermal, at about 6000 BP, ground ice in Eurasia retreated northward by several hundred kilometres. In the interglacial Stage 5e, at about 120 000 BP, global sea-level rose by over 6 m. Fluctuations of mountain glaciers depend on mesoscale “weather” and on their mechanical response to it. Any melting of the Greenland ice sheet is likely to be slow in human terms. The West Antarctic ice sheet (its base below sea-level) is susceptible to an ungrounding, and such an event may have been the cause of the sea-level rise above. The East Antarctic ice sheet is susceptible to mechanical “surges”, which might be triggered by a warming at its margin. Both an ungrounding and a surge might occupy less than 100 yr, and are potetially the most important ice changes in human terms. Modelling studies suggest that a 5°C warming would remove the Arctic pack ice in summer, and this may be the most significant effect for further climatic change. 相似文献