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Vegetation samples from King George Island, Antarctica (62°05'S, 058°23'W) were collected in the austral summer of 2004-2005. Lichens (Usnea aurantiaco-atra and Usnea antarctica), mosses (Sanionia uncinata, Syntrichia princeps and Brachytecium sp.), and one angiosperm (Colobanthus quitensis) species were analyzed for persistent organic pollutants as well as δ(13)C and δ(15)N stable isotopes. The following contaminants were found above the method detection limit (MDL): HCB (0.141-1.06 ng g(-1) dry weight), HCHs (相似文献   
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This paper reports the reconstruction of the contamination history of a large South American industrial coastal area (Santos Estuary, Brazil) using linear alkylbenzenes (LABs). Three sediment cores were dated by 137Cs. Concentrations in surficial layers were comparable to the midrange concentrations reported for coastal sediments worldwide. LAB concentrations increased towards the surface, indicating increased waste discharges into the estuary in recent decades. The highest concentration values occurred in the early 1970s, a time of intense industrial activity and marked population growth. The decreased LAB concentration, in the late 1970s was assumed to be the result of the world oil crisis. Treatment of industrial effluents, which began in 1984, was represented by decreased LAB levels. Microbial degradation of LABs may be more intense in the industrial area sediments. The results show that industrial and domestic waste discharges are a historical problem in the area.  相似文献   
3.
Polychlorinated biphenyls (PCBs) and Polybrominated Diphenyls Ethers (PBDEs) are two highly lipophilic classes of persistent organic pollutants able to resist degradation and with the ability to bioaccumulate through the food chain. In Brazil, there are still few studies on PCBs and PBDEs in aquatic organisms. In this study, we determined the levels of PBDEs and PCBs in three different fish species from the Ilha Grande Bay, located in the southern state of Rio de Janeiro, Brazil. PBDEs levels were very low, with values below the limit of quantification. PCBs concentrations ranged from 2.29 to 27.60 ng g?1 ww in muscle and from 3.41 to 34.22 ng g?1 ww in liver of the three investigated fish species. Significant positive correlations were established between PCBs concentration and fish biometric variables in mullet (length and lipid content) and a statistically significant change between seasons in croaker was observed.  相似文献   
4.
Albatrosses and petrels (Procellariiformes) are migratory oceanic birds of considerable conservational interest. Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed in the subcutaneous fat, liver and muscle of 100 birds belonging to eight species of Procellariiformes collected during their migration period in southern Brazil, one of the most important feeding areas for these species. Although the profiles of PCBs and OCPs were similar among the individuals, with predominance of penta, hexa and heptachlorobiphenyls and pp-DDE, organochlorine concentrations exhibited a high degree of intra-species variability. The influence of body condition during the migration period in the distribution of organochlorine contaminants was also evaluated, showing that it is a significant factor in the variation and redistribution of these compounds in the tissues of these birds. The intense use of lipid reserves associated to the contamination from organochlorine compounds could be a troubling factor for seabirds with extended breeding periods and that spend most of their lives at sea migrating long distances, such as most of Procellariiformes. Studies on contamination are necessary to improve the knowledge of the threats to these birds and their populations as well as to contribute with information about persistent organic pollutants in the South Atlantic marine environment.  相似文献   
5.
Chlorinated pesticides, PCBs and PBDEs were analysed in nine blubber samples of Atlantic spotted dolphins, Stenella frontalis, incidentally captured during fishing operations in southern and southeastern Brazil between 2005 and 2007. The majority of compounds analysed were detected, suggesting widespread contamination over the region. Although the samples came from a location far from main coastal industrial areas, the results revealed an influence from such sources. Therefore, levels of PCBs (774-23 659 ng g−1 lipid wt.) and PBDEs (23-1326 ng g−1 lipid wt.) detected seem to be related to the movement of individuals throughout near-shore and offshore waters. The sample from a lactating female exhibited a lower level of contamination and a distinct pattern, indicating selective transfer favouring less lipophilic compounds.  相似文献   
6.
This paper describes the first results of polycyclic aromatic hydrocarbons (PAHs) and spheroidal carbonaceous particles (SCPs) in sediment cores of Admiralty Bay, Antarctica. These markers were used to assess the local input of anthropogenic materials (particulate and organic compounds) as a result of the influence of human occupation in a sub-Antarctic region and a possible long-range atmospheric transport of combustion products from sources in South America. The highest SCPs and PAHs concentrations were observed during the last 30 years, when three research stations were built in the area and industrial activities in South America increased. The concentrations of SCPs and PAHs were much lower than those of other regions in the northern hemisphere and other reported data for the southern hemisphere. The PAH isomer ratios showed that the major sources of PAHs are fossil fuels/petroleum, biomass combustion and sewage contribution generally close to the Brazilian scientific station.  相似文献   
7.
The toxicity of butyltin compounds (BTs), mainly tributyltin (TBT), has been reported in different organisms. However, such an analysis in fish after field exposure with reference to the related biomarkers has not been commonly observed in the literature. This study presents the uptake of BTs in the liver of a neotropical marine catfish Cathorops spixii in Paranagua Bay, an important estuarine system located in southern Brazil. Two different areas, close to and distant from the harbor, were used for chemical analysis evaluation of hepatotoxicity through genetic, enzymatic, and histopathological biomarkers. The presence of polycyclic aromatic hydrocarbons in bile was also considered as a biomarker. The results showed a significant relationship between TBT levels and the inhibition of biotransformation enzymes and high occurrence of melanomacrophages in fish collected close to the harbor site. These effects were linked to the absence of TBT metabolites in the liver. In the second site, the presence of DBT was associated with an increase in EROD and GST activity. The larger amount of DNA damage as well as the highest oxidative stress was noted in fish from the less TBT-polluted area, where DBT and bile PAHs occurred. These findings showed different impact levels due to or increased by the chronic exposure of biota to BTs.  相似文献   
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