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211.
Newark Bay, New Jersey, is particularly vulnerable to ecological damage from petroleum and chemical spills, as a result of the enclosed nature and shallow depth of the bay, the high frequency of shipping traffic, and the numerous chemical and petroleum transfer terminals located alongs its shores. To evaluate the potential impacts to the natural resources of this coastal estuarine ecosystem, chemical and petroleum accidents reported to the US Coast Guard (USCG) between 1982 and 1991 were compiled to determine the frequency and volume of these incidents in Newark Bay and in each of its major tributaries. Records obtained from the USCG National Response Center's computerized database indicated that more than 1453 accidental incidents, resulting in the release of more than 18 million US gallons of hazardous materials and petroleum products, occurred throughout Newark Bay during this period of time. The bulk of the materials released to the aquatic environment consisted of petroleum products, specifically No. 6 Fuel Oil (103 spills, 12 829 272 US gal) and gasoline (207 spills, 48 816 US gal). The majority of the reported incidents occurred in the Arthur Kill and its tributaries, as well as in the Kill Van Kull and the Passaic River. The results of this study indicated that the accidental discharge of petroleum and hazardous chemicals represents a significant source of chemical pollution in Newark Bay. Based on the frequency of spills and the volume of materials released to the aquatic environment, it is likely that these events are having a deleterious effect on the Newark Bay ecosystem.  相似文献   
212.
Cellulose decomposition in soils amended over twenty year ago with heavy metal-contaminated sewage sludges was assessed by using the cotton-strip assay. The soils of the Luddington Experiment now contain concentrations of Cu, Ni and Zn in selected plots that approximate to or exceed the statutory limits for these elements in sewage sludge-amended soils. The rates of cellulose decomposition were generally lower in the plots with elevated metal concentrations, relative to uncontaminated sludge-amended and unsludged controls. Generally, the metal-rich plots showed reductions in the time taken to reach 50% cotton-tensile-strength loss (CTSL). However, the reductions could not be consistently related to any one metal. The difference in decomposition rates between treatments was systematically reduced over the duration of a time-course experiment. A lower initial population of the appropriate decomposer community of micro-organisms may account for the observed short-term lag in decomposition rates.  相似文献   
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A teratological assessment of four trihalomethanes in the rat   总被引:7,自引:0,他引:7  
Four trihalomethanes were administered by gavage to Sprague-Dawley rats from day 6 to day 15 of gestation. Chloroform (Ch) was administered at levels of 100, 200 and 400 mg/kg and bromoform (Br), bromodichloromethane (BDCM) and chlorodibromomethane (CDBM) were administered at levels of 50, 100 or 200 mg/kg/day. A separate control was used for each compound. Maternal weight gain was depressed in all groups receiving Ch and at the highest dose levels of BDCM and CDBM. Ch administration caused decreased maternal hemoglobin and hematocrit values at all dose levels and also produced increased serum inorganic phosphorus and cholesterol at the highest dose. Liver enlargement was observed at all dose levels of Ch but in no other treatment groups. Evidence of a fetotoxic response was observed with Ch, CDBM and Br but not BDCM. No dose-related histopathological changes were observed in either mothers or fetuses as a result of treatment. None of the chemicals tested produced any teratogenic effects.  相似文献   
215.
To study problems associated with pesticide container disposal, a small vegetable production area in southwestern Ontario, the Thedford Marsh, was selected as the site for a model study. A container collection system was organized during the 1981 growing season, with collections being made from the ca. 50 growers on the marsh twice each month. In addition to the regular collection program a cleanup service for empty pesticide containers stored on farms or discarded on public lands also was initiated. More than 3600 containers were collected and disposed of at an authorized landfill site. Ca. 2/3 were herbicide containers, ca. 1/4 were insecticide containers, and 3% were fungicide containers. Unrinsed containers contained as much as 5 1/2% of the original contents with an average of 1%. Containers rinsed by the triple rinse method or using rinsing devices (E-Z Rinse, JET Rinse) generally contained less than 0.1% of the original content. Some formulations presented rinsing problems due to settling and caking. The results indicated that, while unacceptable quantities of pesticide residues remain in unrinsed containers, most rinsed pesticide containers will be acceptable for disposal at municipal sanitary landfill sites.  相似文献   
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We measured the frequency with which leaves of trees in the Ohio River Valley produced ethanol aerobically, to determine if aerobic ethanol production might provide a viable field assay for air pollution stress. Leaves were collected from trees during the summers of 1985 and 1986 and ethanol production was determined using headspace GC. Frequency of ethanol production was compared with environmental factors, including air pollution concentrations. We found frequent foliar ethanol production and elevated alcohol dehydrogenase activity in the leaves of several species of trees in the Ohio River Valley, USA. The ethanol concentrations measured were often equivalent to those produced by anaerobic leaves. Ethanol production was associated with hot, hazy weather and elevated NO(2) concentrations. Ethanol production was more frequent in urban and industrialized areas. Ethanol production was not associated with natural stresses such as flooding and herbivory. We propose that aerobic ethanol production is the result of cell acidification due to the accumulation of acidic gases in the cytoplasm. The use of ethanol production as a diagnostic tool for detecting stress imposed by acidic gases is discussed.  相似文献   
220.
The loss of HCH (hexachlorocyclohexane) at an application rate of 25 kg ha(-1) was studied under field conditions from two surface soil layers, each of 7.5 cm, at two sites in Delhi. The soil at both sites was sandy loam type, with a pH of 8.2, and 0.8 to 1.0% organic matter content. At site 1, which was kept fallow and not watered, the upper 7.5-cm layer of soil initially lost HCH more rapidly than the lower layer. The half-life of the HCH in the upper and lower 7.5-cm layers was 21 and 41 days, respectively, and it was 26 days for the total HCH in the combined 15-cm soil layer. At site 2, which contained ornamental plants and was watered regularly, there was not much difference in the loss of HCH between the upper and lower layers. The half-life of HCH was 17 and 25 days for the upper and lower 7.5-cm layers, respectively, and it was 20 days for the total 15-cm soil layer, at this site. The loss was greatest initially at the sites, and was faster in wet soil than in dry soil.  相似文献   
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