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1.
The feathers of 277 Black, Common and Brünnich's Guillemot from the Baltic, Kattegat, Faroe Islands and Greenland were analysed for mercury. The levels were found to be higher in the Baltic and the Kattegat compared to the Faroe Islands and Greenland. While the levels were almost constant for the last two areas a substantial increase during this century was found for the Baltic and the Kattegat. In Common Guillemots from the Baltic a decrease was indicated after 1969. In general the mercury levels were higher for Black Guillemots living close to the coast compared to the Uria sp. living off-shore. The inhomogeniety of the mercury load near the shore was indicated by a large individual variation within a colony of Black Guillemots. This variation was reinforced by differences in migration and feeding habits. It has been shown by analysis of individuals recaptured during successive years that the year to year variation of one individual is considerably smaller.It is concluded that chronological series based on feathers from sea birds and museum collections may contribute to the elucidation of the long term trend of mercury pollution at sea. 相似文献
2.
Frias JE Gil MN Esteves JL García Borboroglu P Kane OJ Smith JR Boersma PD 《Marine pollution bulletin》2012,64(6):1265-1269
Feathers are useful to determine mercury (Hg) contamination. We evaluated the mercury concentration in feathers of Magellanic penguins (Spheniscus magellanicus) age 1.5 years to 25 years at Punta Tombo, Argentina before and during their molt. Mercury ranged between <1.4 and 367 ng/g dry weight, with three extreme high values (8996 ng/g, 3011 ng/g and 1340 ng/g) all in young adults. The median concentration was lowest for juveniles and significantly higher for adults but with high variation among older adults. Males and females had similar mercury loads. Compared with other penguin species, concentrations in Magellanic penguins were low. Mercury levels for Magellanic penguins in the Southwest Atlantic for older adults averaged 206±98 ng/g, and serve as a baseline for biomonitoring and/or ecotoxicological studies. 相似文献
3.
Two types of sediments, one of them highly polluted by the pulp and chemical industry and the other one polluted by the urban type of sewage, have been analysed for their content of methylmercury and inorganic mercury. The rate of the formation of methylmercury in sediment from inorganic mercury (II) and the decomposition of methylmercury and phenylmercury have been investigated using 203mercury compounds. It has been found that the rates of both processes depend on the experimental conditions. The quickest formation of methylmercury has been observed under the Procedure C which simulates the natural conditions. The lower the rate of demethylation of methylmercury the higher the equilibrium concentration of methylmercury which has been found in sediments. 相似文献
4.
The metabolism of inorganic mercury has been studied in stationary cultures of planktonic algae Chlorella kessleri, Scenedesmus obliquus and Microcystis incerta that were exposed for 14 days to the concentration of 2 × 10?7 M of Hg(II). Individual chemical forms of mercury were determined in algae and in the culture medium at regular intervals. All the studied phytoplankton species started to metabolize mercury immediately after its application, with the exception of the blue-green alga Microcystis incerta. The accumulation of mercury proceeds without interruption till the end of the experiment. After a 14 days cultivation about 60… 80% of added mercury was present in algal cells and the portion of mercury washable from the cell surface did not exceed 2%. It was found that more than 99,5% of mercury in cultivation medium and more than 99,5% of mercury in algae was present in the form of Hg(II). A transformation of inorganic mercury to methyl-, or phenyl-mercury due to the action of algae was not observed. 相似文献
5.
Mercury content of the water column estimated along Thana Creek/Bombay Harbour gave a standing stock of about 77 kg in excess of the expected background. Mercury concentration in sediment from 23 locations which varied from 0.17 to 8.21 ppm (dry weight) with marked increase from the harbour to the creek region suggests substantial mercury input in the head region. Chemical extraction by hydrogen peroxide indicated that more than 70% of mercury was leachable and probably organically bound. The mercury enriched layer in the sediment cores was about 10–25 cm in the creek region and 0–8 cm in the harbour area. The data has been used to calculate an excess of 14 tonnes of mercury over the natural background. Analysis of a few zooplankton and benthic samples from the creek region gave indication of bioaccumulation of mercury. 相似文献
6.
Mercury concentrations in surface intertidal sediments from estuarine and coastal environments of the Northeastern Irish Sea are reported. This region has two inputs of mercury contaminated effluents from chlor-alkali factories, and localized mercury contamination of sediments fairly similar to that reported for the Rhine has been found in the Wyre estuary. The present results for the Mersey estuary agree well with others reported in the lierature. Coastal sediments are much less contaminated than the estuarine deposits, and in all the environments studied strong correlations between mercury concentration, total organic carbon and < 63 μm grainsize fraction contents have been found. 相似文献
7.
Muscle samples from four species of commercially sought shark have been analysed for total mercury and the mercury concentration related to the size of the fish. 相似文献
8.
Ramalhosa E Pereira E Vale C Válega M Monterroso P Duarte AC 《Marine pollution bulletin》2005,50(11):1218-1222
Determinations of dissolved reactive and total dissolved mercury, particulate and sedimentary mercury, dissolved organic carbon (DOC), particulate organic carbon (POC) and suspended particulate matter (SPM) have been made in the estuary of river Douro, in northern Portugal. The estuary was stratified by salinity along most of its length, it had low concentrations of SPM, typically <20 mg dm(-3), and concentrations of DOC in the range <1.0-1.8 mg dm(-3). The surface waters had a maximum dissolved concentration of reactive mercury of about 10 ng dm(-3), whereas for the more saline bottom waters it was about 65 ng dm(-3). The surface waters had maximum concentrations of total suspended particulate mercury of approximately 7 microg g(-1) and the bottom waters were always <1 microg g(-1). Concentrations of mercury in sediments was low and in the range from 0.06 to 0.18 microg g(-1). The transport of mercury in surface waters was mainly associated with organic-rich particulate matter, while in bottom waters the dissolved phase transport of mercury is more important. Lower particulate organic matter, formation of chlorocomplexes in more saline waters and eventually the presence of colloids appear to explain the difference of mercury partitioning in Douro estuarine waters. 相似文献
9.
The uptake of inorganic mercury and phenylmercury by fish directly from water as well as sorbed on food and the release of both forms of mercury has been investigated in order to determine the cumulation and release constants. The radiochemical analysis of different forms of mercury has shown that phenylmercury is rapidly transformed in fish into inorganic mercury, which is slowly transformed into methylmercury. 相似文献
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11.
Of recent, adsorption process has gained a lot of attention as a cheap and effective means of removing trace metals from wastewater prior to discharge into water bodies. Being flexible in design and operation, the process has enabled an optimal recovery of trace metals such that the treated effluents meet the desired standards for waste disposal. Mercury is a toxicant released into the environment from natural and anthropogenic sources. It is notorious for having an unusual tendency to bio‐accumulate and persist in the food chain. Presence of mercury in food, especially those of aquatic sources has drastic implications on human health. Therefore, efforts have been made to develop and optimize low‐cost activated carbon (AC) as adsorbents for scavenging mercury from aqueous effluents. Herein, how mercury accumulates across the food chain, its health implications, and the recent advancement in the use of low‐cost ACs as adsorbent for trapping mercury from wastewater are highlighted. Relationship between the mercury removal efficiency and the surface morphology of the adsorbents as well as the influence of prevailing experimental condition on the sorption process were addressed. Challenges and future prospects of the use of low‐cost adsorbents in addressing mercury pollution in the environment are discussed. 相似文献
12.
Biotransformation of phenyl and methyl mercury chloride was studied in experiments with planktonic algae Chlorella kessleri, Scenedesmus obliquus and blue-green algae Microcystis incerta. To algal cultures cultivated in an inorganic medium the labelled phenyl or methyl mercury hydroxide was added separately in the phase of the logarithmic growth, the resultant concentration being 3.2 × 10?7 M. In intervals of 0, 1, 3, 7, 10 and 14 days samples of the algae and medium were analysed for the total amount of mercury and for the presence of phenyl or methyl mercury. It was found that both methyl and phenyl mercury had accumulated very rapidly in the algae and that up to 70% of 203Hg added was present in the algae during the first 72 hours of the experiment. From the 2nd day onwards, however, methyl and phenyl mercury changed rapidly into inorganic mercury so that by the end of the experiment almost all of the mercury present in algae and the medium was in the form of inorganic mercury. 相似文献
13.
Hans Ulrik Riisgård 《Marine pollution bulletin》1984,15(4):129-133
High concentrations of mercury have been measured in mussels (Mytilus edulis) collected in two ‘hot spot’ areas: (1) near a closed-down chemical factory on the west coast of the Limfjord, and (2) on groynes in the immediate vicinity of a chemical deposit in the dunes on the Danish west coast. By collecting comparable samples of mussels from chains of buoys, the mercury pollution in the western Limfjord could be traced 50–100 km into the central and innermost parts of the Limfjord as a gradual decreasing mercury concentration gradient. By collecting mussels from groynes north and south of the chemical deposit, it was possible to monitor the relative extent of the mercury leakage to the North Sea before and after the excavation of the deposit. The investigations have demonstrated the applicability of M. edulis as a monitoring organism for mercury when importance is attached to concentration gradients and distribution patterns in well defined and homogeneous samples of mussels collected from natural populations. 相似文献
14.
Plankton of mixed composition has been collected from Sorfjørden and Hardangerfjørden, on the west coast of Norway and analysed for total mercury by flameless atomic absorption. Different methods of decomposing the samples prior to analysis were tested, showing no significant variations in the recovery of mercury. The high levels of mercury (0.52-25.21 ppm dry weight) are apparently associated with a source of industrial pollution. Indications of higher mercury concentrations in phytoplankton than in zooplankton were noticed and suggest a lack of food chain amplification within the lower trophic levels. 相似文献
15.
Ocean Dynamics - Residual mercury dynamic has been the research emphasis since mercury contamination was publicly recognized in Minamata Bay. Simulation of mercury distribution and transport... 相似文献
16.
In this study, headspace single drop microextraction (HS‐SDME) method in combination with electrothermal atomic absorption spectrometry (ETAAS) method was developed and validated for the speciation and determination of inorganic mercury (iHg) and methylmercury (MeHg). MeHg and iHg species were reduced to volatile methylmercury hydride (CH3HgH) and elemental mercury, respectively, in the presence of NaBH4 and trapped onto a drop of acceptor phase in the tip of a microsyringe. Thiourea and ammonium pyrrolydinedithiocarbamate (APDC) were tested as the acceptor phase. The experimental parameters of the method such as microextraction time, temperature, NaBH4 concentration, acceptor phase concentration, and pH of the medium were investigated to obtain distinctive conditions for mercury species. Possible interference effects have also been investigated. In order to validation of the method, analytical figures of merits such as accuracy, precision, limit of detection (LOD), limit of quantitation (LOQ), and linear working range have been evaluated. Accuracy of the method has been verified by analyzing certified reference materials (BCR 453 Tuna fish) and spiked samples. The proposed method was applied for the speciation and determination of mercury species in water and fish samples. Mercury species (MeHg and iHg) have been determined in the real samples with a relative error less than 10%. 相似文献
17.
During April 1975 thirty-six muscle samples of six predacious species of fish from the Andaman sea were collected for an analysis of their total mercury concentrations. The total mercury levels ranged from 0.026 to 0.234 ppm in yellowfin tuna (Neothunnus albacora), from 0.027 to 0.233 ppmin bigeye tuna (Parathunnus sibi), and from 0.057 to 0.478 ppm in four species of shark. Statistical analysis also showed positive linear regression and there was correlation between the mercury concentration and the weight of the yellowfin tuna, bigeye tuna, and shark. The rates of total mercury accumulation in yellowfin and bigeye tuna were not significantly different. A comparison between the total mercury level in the Andaman yellowfin and the Central Pacific yellowfin tuna is discussed. 相似文献
18.
Total mercury content has been determined in three tissues of the intertidal mussel Mytilus californianus collected at locations along the southern California coast and at island control stations. The apparent influence of certain harbours and municipal wastewater outfalls was reflected by the relatively higher levels of mercury in all tissues of mussels from these areas. In general, the concentrations reported here are lower than those in mussels on west European coasts. 相似文献
19.
Sixteen young Common Terns (Sterna hirundo) from colonies on the south shore of Long Island, New York, had fairly consistent levels and tissue distribution patterns of total mercury in blood, liver, kidney, muscle, brain and feathers. Levels were highest in liver, blood and feathers, and were lower in muscle and brain. The latter two tissues showed low variability across birds, suggesting that they are more static repositories for mercurial compounds. Only slight, non-significant increases were detected in chicks 10–30 days old compared with 1–9 day olds. Four chicks with abnormal feather loss had significantly higher mercury levels than 12 normal chicks. The average intercorrelation among tissues was highest for liver (mean r2 = 0.40) and blood (mean r2 = 0.38). Liver is probably the single best tissue to serve as a surrogate for all others, due to high correlation with other tissues, large size, and ready availability. Use of a single tissue allows one to focus a study in greater detail and at lower cost than if several tissues were assayed. 相似文献
20.
— The aims of this study were to estimate the total amount of mercury released to the environment during 60 years of gold mining (1867–1926) at Gympie, Queensland, Australia and to measure the mercury levels in soil samples surrounding the mining activity. We estimated that 1902 tonnes of mercury was released to the environment and about 1236 tonnes of which was released to the air. The mean mercury in the soil samples in the vicinity of the Scottish battery varied from 1.07 to 99.26 μg g?1 as compared to 0.075 μg g?1 as background mercury concentrations. The maximum mercury concentration measured in sediments of the Langton Gully was 6.12 μg g?1. These results show that large amount of mercury was used in this area during gold mining. Since mining is active in the area and Langton Gully flows into Mary River, we therefore, recommend that mercury concentration in air and fish should be monitored. 相似文献