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561.
Ethylene oxide (EO) is mainly used as a chemical intermediate and as a fumigant and sterilizing agent. Through its manufacturing and intended uses, EO may be released into the environment. Therefore, an assessment of the environmental significance of those potential emissions was conducted. Data were collected describing pertinent physical properties, degradation and other loss mechanisms that control the fate of EO in the environment. Available aquatic and terrestrial ecotoxicity data were assembled and used as the basis of calculating critical toxicity values to characterize hazard. Environmental compartment concentrations of EO were calculated using Level III fugacity-based modeling. Six scenarios were developed to account for different climatic conditions in various portions of the US. Finally, potential regional-scale risks to aquatic and terrestrial wildlife were determined. In the conceptual model that was developed in this assessment, EO diffuses into air, partitions between environmental compartments, is transported out of the different compartments via advection, and undergoes abiotic and biological degradation within each compartment. All known emissions within the continental USA were assumed to enter a modeled region roughly the size of the State of Ohio. Organisms (receptors) were assumed to dwell in both terrestrial and aquatic compartments. Receptors were assumed to include small mammals, soil invertebrates, water column (pelagic) organisms, and sediment benthos. The goal of this assessment was to characterize any potential adverse risks to terrestrial and aquatic wildlife populations. Hazard Quotients (HQ) were calculated by dividing predicted concentrations of EO in air, water, sediment, and soil by their critical toxicity values. Maximum calculated HQ values in air were 1.52x10(-7), in water were 1.17x10(-5), in sediment were 2.25x10(-4), and in soil were 1.37x10(-5). The results of this assessment suggest that EO as currently manufactured and used does not pose adverse risks to aquatic or terrestrial wildlife. In all cases, the HQ values were much less than the maximum desired HQ value of 1.0 (4,400-6,600,000 times), indicating that the potential for diffuse emissions of EO to pose adverse environmental risks is quite low. 相似文献
562.
Invasions of nonnative species such as zebra mussels can have both ecological and economic consequences. The economic impacts
of zebra mussels have not been examined in detail since the mid-1990s. The purpose of this study was to quantify the annual
and cumulative economic impact of zebra mussels on surface water-dependent drinking water treatment and electric power generation
facilities (where previous research indicated the greatest impacts). The study time frame was from the first full year after
discovery in North America (Lake St. Clair, 1989) to the present (2004); the study area was throughout the mussels’ North
American range. A mail survey resulted in a response rate of 31% for electric power companies and 41% for drinking water treatment
plants. Telephone interviews with a sample of nonrespondents assessed nonresponse bias; only one difference was found and
adjusted for. Over one-third (37%) of surveyed facilities reported finding zebra mussels in the facility and almost half (45%)
have initiated preventive measures to prevent zebra mussels from entering the facility operations. Almost all surveyed facilities
(91%) with zebra mussels have used control or mitigation alternatives to remove or control zebra mussels. We estimated that
36% of surveyed facilities experienced an economic impact. Expanding the sample to the population of the study area, we estimated
$267 million (BCa 95% CI = $161 million–$467 million) in total economic costs for electric generation and water treatment
facilities through late 2004, since 1989. Annual costs were greater ($44,000/facility) during the early years of zebra mussel
infestation than in recent years ($30,000). As a result of this and other factors, early predictions of the ultimate costs
of the zebra mussel invasion may have been excessive. 相似文献
563.
Burger J Gochfeld M Powers CW Kosson DS Halverson J Siekaniec G Morkill A Patrick R Duffy LK Barnes D 《Journal of environmental management》2007,85(1):232-244
It is increasingly clear that a wide range of stakeholders should be included in the problem formulation phase of research aimed at solving environmental problems; indeed the inclusion of stakeholders at this stage has been formalized as an integral part of ecological risk assessment. In this paper, we advocate the additional inclusion of stakeholders in the refinement of research methods and protocols and in the execution of the research, rather than just at the final communication and reporting phase. We use a large study of potential radionuclide levels in marine biota around Amchitka Island as a case study. Amchitka Island, in the Aleutian Island Chain of Alaska, was the site of three underground nuclear tests (1965-1971). The overall objective of the biological component of the study was to collect a range of marine biota for radionuclide analysis that could provide data for assessing current food safety and provide a baseline for developing a plan to monitor human and ecosystem health in perpetuity. Stakeholders, including regulators (State of Alaska), resource trustees (US Fish and Wildlife Service, State of Alaska), representatives of the Aleut and Pribilof Island communities, the Department of Energy (DOE), and others, were essential for plan development. While these stakeholders were included in the initial problem formulation and approved science plan, we also included them in the refinement of protocols, selection of bioindicators, selection of a reference site, choice of methods of collection, and in the execution of the study itself. Meetings with stakeholders resulted in adding (or deleting) bioindicator species and tissues, prioritizing target species, refining sampling methods, and recruiting collection personnel. Some species were added because they were important subsistence foods for the Aleuts, and others were added because they were ecological equivalents to replace species deleted because of low population numbers. Two major refinements that changed the research thrust were (1) the inclusion of Aleut hunters and fishers on the biological expedition itself to ensure that subsistence foods and methods were represented, and (2) the addition of a fisheries biologist on a NOAA research trawler to allow sampling of commercial fishes. Although the original research design called for the collection of biota by Aleut subsistence fishermen, and by a commercial fishing boat, the research was modified with continued stakeholder input to actually include Aleuts and a fisheries biologist on the expeditions to ensure their representation. The inclusion of stakeholders during the development of protocols and the research itself improved the overall quality of the investigation, while making it more relevant to the interested and affected parties. Final responsibility for the design and execution of the research and radionuclide analysis rested with the researchers, but the process of stakeholder inclusion made the research more valuable as a source of credible information and for public policy decisions. 相似文献
564.
There is a science‐practice gap in organizational behavior (OB) whereby entire bodies of scholarly knowledge are ignored by practitioners. We identify research needed to improve performance management practices that is likely to enhance the relevance of OB in the eyes of practitioners and thus help reduce the science‐practice gap. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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568.
Reasons for the current siting impasse, including participatory activism, regulatory failure, the multiplication of considered interests, and the “investigative caveat,” are reviewed, and the existing logic of regulator behavior, viewed as a rational choice model, is summarized. Three sets of goals for agency participants are identified: personal goals of agency decision-makers, organizational goals of the agency as a whole, and goals of agency clients; and the incentive system of a new administrative agency structured so as to make satisfaction of these goals contribute toward informed and impartial decision-making. Major structural components of the agency would be a Director, a Corps of Examiners, counsel(s) for special interest(s) of special merit, a Public Counsel, and a Research and Information Office. The model is applied to the case of a regional or state-level agency to handle power plant siting. 相似文献
569.
Christian A. Chisholm Fotini Vavelidis Mark A. Lovell Lawrence Sweetman Charles R. Roe Diane S. Roe Frank E. Frerman William G. Wilson 《黑龙江环境通报》2001,21(10):856-859
We report the occurrence of multiple acyl-CoA dehydrogenase deficiency (MADD) in two consecutive pregnancies in a young, Caucasian, non-consanguineous couple. In the first pregnancy, the maternal serum α-fetoprotein was elevated. A sonogram showed growth delay, cystic renal disease, and oligohydramnios; the parents decided to terminate the pregnancy. Postmortem examination confirmed the cystic renal disease and showed hepatic steatosis, raising the suspicion of a metabolic disorder. The diagnosis of MADD was made by immunoblot studies on cultured fibroblasts. In the subsequent pregnancy, a sonogram at 15 weeks' gestation showed an early growth delay but normal kidneys. The maternal serum and amniotic fluid concentrations of α-fetoprotein were elevated, and the amniotic fluid acylcarnitine profile was consistent with MADD. In vitro metabolic studies on cultured amniocytes confirmed the diagnosis. A follow-up sonogram showed cystic renal changes. These cases provide additional information regarding the evolution of renal changes in affected fetuses and show a relationship with elevated α-fetoprotein, which may be useful in counseling the couple at risk. MADD should be considered in the differential diagnosis of elevated α-fetoprotein and cystic renal disease. Early growth delay may be an additional feature. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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