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1.
The polychlorinated biphenyls (PCBs) and DDT may bioaccumulate in the aquatic food web and have been of great concern due to their toxic effects on wildlife and human health. There is evidence showing that fish in the human diet contributes at a significant proportion to the total intake of PCBs and other organochlorine compounds, particularly fish with higher fat levels. This study investigated the concentration of PCBs and DDTs in muscle tissues of samples of the blue shark (Prionace glauca) and a swordfish (Xiphias gladius) from east Brazilian coast and estimate the human exposure to total DDTs through the consumption of both the species. Samples of the each species were caught between August and September 2001. The mean concentration for summation operator PCBs in P. glauca was 3.15 ng/g w.w. and the summation operator DDTs was 0.93 ng/g w.w. The mean concentration of summation operator PCBs in X. gladius was 6.50 ng/g and the mean of summation operator DDTs was 2.47 ng/g. The estimated daily intake of summation operator DDT through X. gladius or P. glauca consumption can be considered safe since it contributes to less than 0.1% of the limit of acceptable daily intake (ADI) of summation operator DDT proposed by WHO.  相似文献   

2.
Liver of blue shark (Prionace glauca) specimens from the South-Eastern Mediterranean Sea were analyzed for the presence of polychlorinated biphenyls (PCBs), including coplanar congeners, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). PCBs were the dominant chemicals, followed by PCDFs and PCDDs. The pattern of PCB congener concentrations in the hepatic tissue was dominated by higher chlorinated compounds. The specific profile of toxic PCDD/F congeners was characterized mainly by 2,3,7,8-TCDF and 2,3,7,8-TCDD, followed by 1,2,3,6,7,8-HxCDD and 2,3,4,6,7,8-HxCDF. The total 2,3,7,8-TCDD toxic equivalent (TEQs) was 149 pg g−1 lipid wt. The profile of TEQ shows that PCDDs present the greatest risk to this species contributing to total toxicity with a percentage approximately of 60%, while the contribution of PCDFs and DL-PCBs is almost the same being 22.4% and 21.6%, respectively. Further investigations are urgently needed to characterize the PCDD/Fs contamination levels not only in elasmobranch fish but in all Mediterranean marine biota.  相似文献   

3.
Mercury, methyl-mercury (MeHg) and selenium were determined in digestive gland and mantle of Octopus vulgaris, from three areas of the Portuguese coast. To our knowledge these are the first data on MeHg in cephalopods. Concentrations were higher in the digestive gland and percentage of MeHg in mantle. Enhanced Hg and MeHg levels were obtained in digestive gland of specimens from Olhão (3.1-7.4 and 2.0-5.0 μg g−1, respectively). Differences between areas may be partially related to Hg availability. Relationships between concentrations in mantle and digestive gland pointed to proportional increases of Hg and MeHg in tissues of specimens from Matosinhos and Cascais, but relatively constant values in mantle of individuals from Olhão (higher contamination). Se:Hg molar ratio in digestive gland was 32 and 30 in octopus from Matosinhos and Cascais, respectively, and 5.4 from Olhão. The proximity to the unit suggests demethylation as response to elevated MeHg levels in digestive gland.  相似文献   

4.
More than half of pygmy sperm whales (Kogia breviceps) that strand exhibit signs of cardiomyopathy (CMP). Many factors may contribute to the development of idiopathic CMP in K. breviceps, including genetics, infectious agents, contaminants, biotoxins, and dietary intake (e.g. selenium, mercury, and pro-oxidants). This study assessed trace elements in K. breviceps at various stages of CMP progression using fresh frozen liver and heart samples collected from individuals that stranded along US Atlantic and Gulf coasts between 1993 and 2007. Standard addition calibration and collision cell inductively coupled plasma mass spectrometry (ICP-MS) were employed for total Se analysis and pyrolysis atomic absorption (AA) was utilized for total Hg analysis to examine if the Se/Hg detoxification pathway inhibits the bioavailability of Se. Double spike speciated isotope dilution gas chromatography ICP-MS was utilized to measure methyl Hg and inorganic Hg. Immunoblot detection and colorimetric assays were used to assess protein oxidation status. Data collected on trace elements, selenoproteins, and oxidative status were evaluated in the context of animal life history and other complementary histological information to gain insight into the biochemical pathways contributing to the development of CMP in K. breviceps. Cardiomyopathy was only observed in adult pygmy sperm whales, predominantly in male animals. Both Hg:Se molar ratios and overall protein oxidation were greater in males than females and increased with progression of CMP.  相似文献   

5.
Lepom P  Irmer U  Wellmitz J 《Chemosphere》2012,86(2):202-211
Mercury concentrations have been analysed in bream (Abramis brama L.) and zebra mussels (Dreissena polymorpha) collected at 17 freshwater sites in Germany from 1993-2009 and 1994-2009, respectively, within the German Environmental Specimen programme. Mercury concentrations in bream ranged from 21 to 881 ng g−1 wet weight with lowest concentrations found at the reference site Lake Belau and highest in fish from the river Elbe and its tributaries. Statistical analysis revealed site-specific differences and significant decreasing temporal trends in mercury concentrations at most of the sampling sites. The decrease in mercury levels in bream was most pronounced in fish from the river Elbe and its tributary Mulde, while in fish from the river Saale mercury levels increased. Temporal trends seem to level off in recent years. Mercury concentrations in zebra mussels were much lower than those in bream according to their lower trophic position and varied by one order of magnitude from 4.1 to 42 ng g−1 wet weight (33-336 ng g−1 dry weight). For zebra mussels, trend analyses were performed for seven sampling sites at the rivers Saar and Elbe of which three showed significant downward trends. There was a significant correlation of the geometric mean concentrations in bream and zebra mussel over the entire study period at each sampling site (Pearson’s correlation coefficient = 0.892, p = 0.00002). A comparison of the concentrations in bream with the environmental quality standard (EQS) of 20 ng g−1 wet weight set for mercury in biota by the EU showed that not a single result was in compliance with this limit value, not even those from the reference site. Current mercury levels in bream from German rivers exceed the EQS by a factor 4.5-20. Thus, piscivorous top predators are still at risk of secondary poisoning by mercury exposure via the food chain. It was suggested focusing monitoring of mercury in forage fish (trophic level 3 or 4) for compliance checking with the EQS for biota and considering the age dependency of mercury concentrations in fish in the monitoring strategy.  相似文献   

6.
Total mercury (Hg) concentrations were measured in the fur, brain and liver of wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada. Total Hg concentrations in fur were strongly correlated with levels in the brain and liver. There was no difference in tissue concentrations between male and female mink; however, female otters had significantly higher fur, brain and liver Hg levels than males. Similarly, there was not a significant relationship between Hg concentration and age of mink, whereas in otters, Hg concentrations in all three tissues decreased significantly with age. In both species, only a very small percentage of the variability in Hg concentration was explained by age. After adjusting the data for site-to-site differences in Hg levels, Hg concentrations in the fur of mink infected by the parasite, Dioctophyma renale, were found to be significantly higher than Hg levels in uninfected mink.  相似文献   

7.
Cakirogullari GC  Secer S 《Chemosphere》2011,85(11):1713-1718
The concentrations of indicator polychlorinated biphenyls (PCBs) and organochlorine insecticides were determined in bonito (Sardasarda L. 1758) and anchovy (Engraulisencrasicolus L. 1758) from the Black Sea, Turkey. Concentrations of total indicator PCBs ranged between <1-17.0 in bonito, and <1-17.5 ng/g fresh weight in anchovy, and total of 1,1,1-trichloro-2,2-bis-chlorophenyl-ethane and its metabolites’ (DDTs) concentrations ranged between 13.4-26.3, and 2.96-19.0 ng/g fresh weight in bonito and anchovy respectively. PCB 52, p,p′-DDE and endosulfan (α + β) were found dominant in both of the fish species. Except endosulfan, and some DDT metabolites, none of the studied organochlorine pesticides was detected in the fish samples. Concentrations of PCBs in anchovy were found higher than those in bonito, whereas DDT and endosulfan concentrations were found similar in both of the fish species. All of the fish samples had residue concentrations below the maximum residue limits (MRL) recommended by FAO/WHO Codex Alimentarius Commission.  相似文献   

8.
《Chemosphere》2012,86(11):1713-1718
The concentrations of indicator polychlorinated biphenyls (PCBs) and organochlorine insecticides were determined in bonito (Sarda sarda L. 1758) and anchovy (Engraulis encrasicolus L. 1758) from the Black Sea, Turkey. Concentrations of total indicator PCBs ranged between <1–17.0 in bonito, and <1–17.5 ng/g fresh weight in anchovy, and total of 1,1,1-trichloro-2,2-bis-chlorophenyl-ethane and its metabolites’ (DDTs) concentrations ranged between 13.4–26.3, and 2.96–19.0 ng/g fresh weight in bonito and anchovy respectively. PCB 52, p,p′-DDE and endosulfan (α + β) were found dominant in both of the fish species. Except endosulfan, and some DDT metabolites, none of the studied organochlorine pesticides was detected in the fish samples. Concentrations of PCBs in anchovy were found higher than those in bonito, whereas DDT and endosulfan concentrations were found similar in both of the fish species. All of the fish samples had residue concentrations below the maximum residue limits (MRL) recommended by FAO/WHO Codex Alimentarius Commission.  相似文献   

9.
In order to study the influence of microorganisms on the mercury biogeochemistry, the metal content and the structure of microbial communities were determined in sediments from stations along the Adour Estuary. The comparison of the bacterial communities and their distribution in function of the environmental parameters by Canonical Correspondence Analysis (CCA) revealed the influence of metals on the bacterial communities structure. Sediments where the bacterial communities are mostly influenced by methylmercury were incubated in slurries with or without mercury, under oxic and anoxic conditions. Methylmercury production was detected in the anoxic biotic slurries with a net methylation yield of 0.3% after 24 h. CCA based on T-RFLP profiles revealed the impact of mercury addition on the bacterial communities structure. In addition, 17 bacterial strains, mainly sulphate-reducing bacteria involved in mercury methylation, were isolated and identified.  相似文献   

10.
The concentrations of mercury (Hg), cadmium (Cd), lead (Pb) and selenium (Se) were determined in liver, kidney and muscle samples from 20 Baltic ringed seals (Phoca hispida botnica) (3-32 years), and from 17 ringed seals (Phoca hispida) (0-20 years) from Svalbard, in the Arctic. The concentrations of Hg and Se were considerably higher in the Baltic ringed seals, but the Cd concentrations lower than in the Svalbard ringed seals. There was no big geographical difference with respect to Pb concentrations. Se and Hg concentrations showed a significant positive correlation in both regions. By comparison with earlier studies on Baltic seals, the metal concentrations have remained at the same level since the 1980s. Of the metals we studied, only the level of Hg in Baltic ringed seals can be considered high (mean 53 mg/kg, range 6.5-124 mg/kg wet wt. for liver), but probably not high enough to cause metal intoxication. No pathological changes associated with metal intoxication were observed in the seals.  相似文献   

11.
12.
The aim of this study was to examine the effects of selenium on concentrations of metabolites and enzyme activities acting as antioxidant markers in liver and kidney of Siberian sturgeon Acipenser baeri. Sturgeons were fed selenium cysteine for 30 and 60 d at 1.25, 5, 20 mg Se kg−1. Selenium level in the control feed was 0.32 mg kg−1. Se concentration was measured in liver, kidney and muscle of every specimen. Sturgeon accumulated Se in tissues with a clear dose-response relationship and the highest Se concentration was recorded in liver. This outcome is lined up with the findings obtained on the antioxidant markers evaluated in both tissues, and in which a dose-response for several biomarkers was recorded in liver. The superoxide dismutase activity in Se-treated fish was generally induced, while catalase activity was lower in liver or unaltered in kidney. The concentrations of glutathione S-transferase, glutathione reductase and total glutathione responded differently for both tissues and were induced in a different way at both endpoints. No changes of glyoxalase I activity were noted for both Se-treated tissues, while for glyoxalase II enzyme in liver a dose-related pattern was found showing a reversible effect (decreased and increased counteractive response) only in the 5 mg kg−1 group. Moreover, the highest Se concentrations did not cause marked changes in malondialdehyde levels of liver and kidney. The enhancement of glutathione peroxidase activity in Se-treated sturgeon might have prevented the lipid peroxidation in both tissues, providing to the Siberian sturgeon a great defense ability versus the prooxidant effect of selenium.  相似文献   

13.
Concentrations of POPs in Great skua eggs from Shetland are among the highest in North Atlantic seabirds, with up to 11,600 μg/kg (ww) DDE and up to 17,900 μg/kg ww ∑PCB. Concentrations of legacy POPs were significantly lower in 2008 than 1980. Decreases were greatest for least persistent compounds. Median ∑PBDEs increased from 99 μg/kg ww in 1980 to 173 μg/kg ww in 2008. There were changes in Great skua breeding season diet, with more adult Herring and Mackerel and less Sandeel. These changes increase exposure to POPs, since Herring and Mackerel accumulate more POPs than Sandeels. In both years, eggs with higher δ15N had higher POP concentrations. In 1980, birds feeding more on demersal discard fish from trawl fisheries and less on Sandeels, had higher POP levels in eggs. In 2008, individuals feeding more on Herring and Mackerel, and less on discards, had higher POP levels in eggs.  相似文献   

14.
The objective of this study was to conduct a comprehensive comparison of the effect on acetylcholinesterase (AChE) from various tissues of Mytilus trossulus caused by in vitro exposure to several pesticides and metals, because results available in the literature are inconsistent, difficult to compare, and sometimes contradict each other. For this purpose, fraction S10 extracted from gills, digestive gland, mantle and muscles, and the whole soft tissue of the mussel was exposed to several pesticides (dichlorvos, chlorpyrifos, fenitrothion, carbofuran and carbaryl) and metals (Cu, Zn, Cd, Hg, Pb) at a wide range of concentrations. AChE was inhibited in 50% or more in all the tissues exposed to dichlorvos, Cu, Hg and the mixture of Cu+Cd, and in some tissues exposed to carbaryl and carbofuran. The IC50 was calculated where possible. No inhibition was found in the case of chlorpyrifos, Cd, Pb, and Zn.  相似文献   

15.
This study aimed at investigating the cellular distribution of Hg in the lichens Cladonia arbuscula subsp. mitis and Peltigera rufescens treated with Hg2+ and at testing if Hg treatment affects selected physiological parameters. In both species, increasing Hg accumulation under increasing Hg supply in the treatment solutions was found. P. rufescens showed a higher intracellular accumulation. Photosynthetic parameters were negatively affected in both species, as indicated by the decrease in photosynthetic pigments content, photosynthetic efficiency and chlorophyll integrity. Cell membranes of both species endured damage as indicated by the increase in the concentration of products of lipid peroxidation and decrease in ergosterol content. Nevertheless, differences between the two species were found, suggesting a differential sensitivity to Hg.  相似文献   

16.
The aim of the present study is the comparative examination of accumulation and detoxification of Cu and Hg in digestive gland and gills of mussels Mytilus galloprovincialis, using atomic absorption spectrophotometry and autometallography. Mussels were exposed to 0.08 mg L−1 Cu, 0.08 mg L−1 Hg, as well as to a mixture of 0.08 mg L−1 Hg and 0.08 mg L−1 Cu for 11 d. After the experimental exposure, animals were kept under laboratory conditions for a detoxification period of 7 d. An antagonistic effect of Cu against to Hg accumulation was noted in the digestive gland of mussels after the experimental exposure, as well as after the detoxification period, supporting the protective role of Cu against to Hg toxicity in this tissue. Digestive gland was suggested as a main organ for Hg accumulation and gills as a target position for Cu accumulation. Additionally, lower time was evaluated for Hg detoxification in the digestive gland and gills of mussels, in relation to those addressed for Cu detoxification in the same tissues. The evaluation of black silver deposits (BSD) extent performed in digestive gland and gills was suggested as a less sensitive approach, in relation to atomic absorption spectrophotometry (AAS), to indentify the concentration of heavy metals in tissues of mussels. The toxic effects of Hg, Cu and a mixture of them on lysosomal system of the digestive cells are also discussed.  相似文献   

17.
Within the past decade, reproductive and health disorders have been reported to occur in unique populations of Atlantic stingrays (Dasyatis sabina) inhabiting certain components of Florida's St. Johns River. Since these irregularities are consistent with the alleged effects of organochlorine (OC) contaminant exposure in other Florida wildlife, the goal of this study was to examine possible associations between OC concentrations and reproduction and/or immune function in stingrays from this river system. Liver concentrations of 30 OC pesticides/pesticide metabolites and total polychlorinated biphenyls (PCBs) were measured and compared in D. sabina collected from four central Florida lakes of the St. Johns River: Lake George, Lake Harney, Lake Jesup, and Lake Monroe. Reproductive biology, serum testosterone and 17beta-estradiol concentrations, and circulating white blood cell counts were examined and compared in stingrays from lakes that were determined to contain low (Lake George), intermediate (Lake Monroe), and high (Lake Jesup) levels of pesticide contamination, based on the results of liver OC assessments. Successful breeding occurred in Lake Jesup stingrays, indicating that the degree of OC accumulation in these animals is not high enough to cause reproductive impairment. However, elevated serum steroid concentrations and white blood cell counts were observed in Lake Jesup stingrays, suggesting that endocrine and immune function may be altered in these animals due to OC exposure and/or other, as yet unknown, ecological factors. Inconsistencies in the reproductive success of Lake Monroe stingrays were observed, confirming earlier reports of reproductive complications in this sub-population. Based on these findings, previous occurrences of reproductive failure in St. Johns River stingrays may be due to environmental factors other than OC exposure.  相似文献   

18.
Comparative studies of biomonitors of trace metal contamination are relatively scarce. We took advantage of a point source pollution in a reservoir (Flix, Spain) to compare trace metal (Hg, Pb, Cd, Se, As, Zn, Cu, Cr) bioaccumulation patterns among 16 food web components. Our results indicate that most organisms are suitable for Hg biomonitoring, whereas other metals are better monitored by only some of them. Biofilms and zebra mussel were the organisms with larger and more diverse biomonitoring capacity. However, we show that using groups of biomonitors increase the scope and strengths of the conclusions and specific goals can be better addressed. We conclude providing an overview of the strengths and weaknesses of the main organisms considered for biomonitoring trace metals in rivers and reservoirs.  相似文献   

19.
Levels of PCBs were determined in two marine organisms, limpets (Patella ullisiponensis aspera) and winkles (Ossilinus atratus), sampled in three stations in the south east coast of Tenerife during 1993. Winkles and limpets exhibited different PCB patterns. Principal Component Analysis (PCA) was used to study the patterns and the relationships among PCBs.  相似文献   

20.
Environmental Science and Pollution Research - In November 2016, the total metal concentrations in nine representative locations in lead (Pb)-zinc (Zn) mining areas, located in Guangdong Province,...  相似文献   

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