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Hair nickel, mercury, cadmium, lead and chromium concentrations were measured from still-born ringed seal pups and from other ringed seal groups from Lake Saimaa in Finland. Nickel concentration was significantly higher in the hair samples of still-born pups as compared to live-born pups and to adult seals. There was assumed to be some connection between the stillbirth of the pups and nickel concentration of the hair. Mercury concentration of the natal hair of pups was significantly higher than the mercury concentration of the first adult hair but no clear connection between stillbirth and mercury pollution was observed. No differences were observed in cadmium, lead and chromium concentrations of the hair of still-born and other ringed seal groups.  相似文献   

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Northern fur seals from the Pribilof Islands, Alaska (St. George Is. and St. Paul Is.) were examined for organochlorine contamination (OC) and whether the organochlorine levels differed between the populations and were at levels that may adversely affect their health. Fur seal blubber and milk samples were obtained from pups, sub-adult males, and adult females on both Pribilof Islands. These samples were analyzed for organochlorine contaminants including dioxin-like PCBs and other selected PCBs and pesticides by high performance liquid chromatography/photodiode array. Results showed that there are clear differences between the two islands in the patterns of fur seal OC distribution. Generally, these differences are confined to the PCBs with only minimal differences in the DDTs. There are also clear biological differences in the levels shown between milk, pup blubber, and sub-adult male blubber. When considering blubber, St. George Is. fur seals show higher OC levels than St. Paul Is., for both pups and sub-adults. On the other hand, milk samples from St. Paul Is. showed higher PCB levels than St. George Is. For the milk, the overall OC levels may impact the immune function of the pups, but are probably of only minimal impact to humans. However, for blubber, the overall toxic equivalency shows levels exceeding those levels recommended for human consumption at St. George Is. and approaching those levels at St. Paul Is. The concentration curves suggest that the movement of OC in and out of milk follows a complex set of reactions dependent on how the OC compounds on a congener level are associated with lipid. In fact, there is some evidence that they may not follow the lipid as closely as we had thought and that lipid levels can vary without impacting the total OC level in the milk.  相似文献   

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The lead, cadmium and mercury content of soft tissues and bone were determined for the common seal (Phoca vitulina) collected from off the coast of East Anglia and the West of Scotland. Lead levels were low in all tissues, cadmium accumulated with age in the kidney of West Scotland seals and mercury accumulated to high levels in the liver of seals from both areas. Comparison of our results with those of other workers, suggests that the rate of mercury accumulation in the liver of seals increases in the order: Canadian Arctic and Atlantic coast < West Scotland < East Anglia < Netherlands coast. Accumulation of mercury in the kidney and spleen of older seals, lends tentative support to the hypothesis that a protective demethylation and retention process in the liver may begin to leak mercury to other tissues at the high concentrations which have been recorded in the liver of older seals, and at the high dose rates which have been used in toxicological experiments.  相似文献   

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Bombay harbour is one of the major sinks, on the western peninsula of the Indian subcontinent, receiving anthropogenic pollutants including heavy metals, radionuclides and hydrocarbons in addition to sewage. To evaluate possible impacts of a few heavy metals on the harbour ecosystem, the distribution patterns of Zn, Mn, Cu, Fe, Co, Ni, Cd, Cr, Pb and Sr in water, sediment and two benthic species, the blood clam Anadara granosa and gobiid mudskipper Boleophthalmus boddaerti were studied over the period 1976–1980. The present levels of the ten elements in biotic and abiotic matrices were found to be far below those that are known to affect adversely the life and quality of benthic communities. Furthermore, the concentrations of these elements in various compartments neither revealed any systematic temporal or spatial fluctuations nor reflected the substantial incease in the total budget over the past 8–12 years. Also these levels were within the range reported in the nearshore and oceanic environs along the west coast. In view of this, the poor growth and high percentage mortality observed in the clam Anadara granosa fished from the Sewri clam bed compared to that of the stock harvested from the Trombay region in the harbour may well be due to anoxic conditions caused by organic pollutants present in the domestic sewage and industrial wastes released in the vicinity of the Sewri clam bed.  相似文献   

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The intertidal mussel Mytilus californianus is a useful indicator of anthropogenic inputs of several trace metals off southern California. Highest metal concentrations were measured in the digestive glands, and no significant differences attibutable to sex were found for this tissue. The distribution of lead appears to be dominated by diffuse inputs, while those of copper, chromium, and silver are most related to urban point sources. No distinct pattern was observed for nickel or zinc.  相似文献   

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Several independent studies of heavy metal pollution in the Severn Estuary and Bristol Channel are in progress. The County Health Department and Public Analyst have been examining the accumulation of metals in marine shore animals and the food chain, and report their results and conclusions.  相似文献   

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Analyses of cadmium, zinc, copper and nickel in the tissues of fish and crustaceans from inshore waters off the Northumberland coast reveal some surprisingly high values.  相似文献   

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The monitoring programme of harmful substances in selected species in the Baltic Sea was started in 1979. In the present study, three-year averages of Zn, Cu, Cd and Pb in cod liver (Hg in cod muscle) and herring muscle are reported. The concentrations of heavy metals in cod show areal differences roughly in accordance with the concentrations of heavy metals in sea water. No significant differences between heavy metal concentrations in North Atlantic and Baltic Sea species were found, except for mercury, for which values in the Baltic Sea species are lower than in those from the North Atlantic.  相似文献   

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Sediments in the upper Saronikos Gulf have been contaminated by heavy metals from the discharge of untreated industrial and domestic wastewater from the area around Athens. Neutron activation analysis indicates concentrations of antimony, arsenic, chromium, gold, mercury, silver and zinc are 8–200 times greater than in the surrounding uncontaminated sediments. The bottom area affected by increased metal concentrations is at least 13 km2 and indicates a nearly radial dispersal pattern from the main outfall with higher concentrations extending to the southeast and southwest.  相似文献   

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