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1.
Environ Pollut ; 241: 155-163, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29804048

RESUMO

Persistent organic pollutants (POPs) such as dichlorodiphenyltrichloroethanes (DDTs), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), and polychlorinated biphenyls (PCBs) have been spreading to Antarctica for over half a century. Penguins are effective indicators of pelagic concentrations of POPs. We synthesized the literature on penguins to assess temporal trends of pelagic contamination in Antarctica, using fat and eggs to monitor changes from 1964 to 2011. DDT/DDE ratios suggest long-range atmospheric transport. Average DDT in fat (ww) increased from 44 ng g-1 in the 1960s, peaked at 171 ng g-1 in the mid-1980s, and then declined slowly to the present level of 101 ng g-1. Temporal trends in HCB contamination rose into the 1990s before declining. ∑HCHs in fat was ∼5 ng g-1 from 1960 to 1979, peaking at 33 ng g-1 during the period 1980-1989 before declining to ∼5 ng g-1 from 1990 to present. PCBs rose substantially from 1970 to 2009 in fat, varying more than DDTs and HCB in both fat and eggs. Antarctic penguins are good biological indicators of global DDT and HCB emissions, but the existing data are insufficient regarding HCHs and PCBs.


Assuntos
Tecido Adiposo/química , Monitoramento Ambiental , Poluentes Ambientais/análise , Óvulo/química , Spheniscidae , Animais , Regiões Antárticas , DDT/análise , Hexaclorobenzeno/análise , Hexaclorocicloexano/análise , Oceanos e Mares , Bifenilos Policlorados/análise , Estudos Retrospectivos
2.
Mar Pollut Bull ; 114(1): 564-570, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27717573

RESUMO

Mercury (Hg) can reach the environment through natural and human-related sources, threatening ecosystems all over the planet due to its well known deleterious effects. Therefore, Antarctic trophic webs, despite being relatively isolated, are not exempt of its influence. To evaluate Hg concentrations in an Antarctic ecosystem, different tissues from 2 species of invertebrates, 2 of fish, 8 of birds, 4 of pinnipeds and at least 5 of vegetation were investigated (n=176). For animals, values ranged from 0.018 to 48.7µgg-1 dw (whole Antarctic krill and Antarctic Fur Seal liver). They were generally correlated to trophic position (assessed by δ15N and δ13C) but also to cephalopods and myctophids consumption. For vegetation, values ranged from 0.014 to 0.227µgg-1 dw (Colobanthus quitensis and an unidentified lichen), with lichens presenting significantly higher values than mosses, likely due to year-round exposure and absorption of animal derived organic matter, as hypothesized by literature.


Assuntos
Baías/química , Ecossistema , Monitoramento Ambiental/métodos , Mercúrio/análise , Poluentes Químicos da Água/análise , Animais , Regiões Antárticas , Aves/metabolismo , Briófitas/química , Briófitas/efeitos dos fármacos , Caniformia/metabolismo , Peixes/metabolismo , Cadeia Alimentar , Invertebrados/química , Invertebrados/efeitos dos fármacos , Ilhas
3.
Mar Pollut Bull ; 77(1-2): 396-9, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24143957

RESUMO

Polybrominated diphenyl ethers (PBDEs) have been gaining much visibility in environmental chemical studies due to their similarity to PCBs and growing reports of harmful effects. The fact that these contaminants have not yet undergone bans or restrictions on the global level underscores the need for data on their occurrence. In the present study, fat samples from 26 White-chinned Petrels (Procellaria aequinoctialis) and 3 Spectacled Petrels (P. conspicillata) collected dead ashore or as bycatch of longline fisheries in southern Brazil were analyzed to determine concentrations of seven congeners (IUPAC #28, 47, 99, 100, 153, 154 and 183). Concentrations of ΣPBDEs ranged from not detectable to 72.70 ng g(-1) (wet weight), comparatively lower than concentrations reported for seabird samples in northern hemisphere. The most detected congeners were 153, 154 and 183. This pattern is close to that previously reported for birds of the same group, but not those from the same region.


Assuntos
Tecido Adiposo/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Éteres Difenil Halogenados/metabolismo , Animais , Aves , Brasil , Feminino , Masculino
4.
Mar Pollut Bull ; 74(1): 435-40, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23830520

RESUMO

Remote islands, such as the São Pedro and São Paulo Archipelago (SPSPA), Brazil, are pristine areas. However, these locations are not exempt from the arrival of anthropogenic agents, such as persistent organic pollutants (POPs). The present study aimed to determine the occurrence and distribution of POPs in the marine biota of the SPSPA. Sample extractions were performed using a microwave-assisted method. The predominant compounds were PCBs and DDTs, which respectively had mean wet weight concentrations of 62.23 and 9.23 ng g(-1) in the tropical two-wing flying fish (Exocoetus volitans), 78.66 and 6.81 ng g(-1) in the brown booby (Sula leucogaster) and 43.40 and 3.03 ng g(-1) in the red rock crab (Grapsus grapsus). Low levels of contaminants suggest a relative degree of isolation. Occurrence and distribution profiles of PCBs support long-range atmospheric transport as the main source of contamination and demonstrate the ubiquity of these pollutants in the marine environment.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água/metabolismo , Animais , Organismos Aquáticos/metabolismo , Biota , Aves/metabolismo , Braquiúros/metabolismo , Brasil , Peixes , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/análise
5.
Mar Pollut Bull ; 64(12): 2650-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23154138

RESUMO

In the present work, fat, skin, liver and muscle samples from Leptonychotes weddellii (Weddell seal, n=2 individuals), Lobodon carcinophagus (crabeater seal, n=2), Arctocephalus gazella (Antarctic fur seal, n=3) and Mirounga leonina (southern elephant seal, n=1) were collected from King George Island, Antarctica, and analysed for POPs (PCBs, organochlorine pesticides and PBDEs) and stable isotopes (δ¹³C and δ¹5N in all tissues but fat). PBDEs could be found in only one sample (L. weddellii fat). Generally, PCBs (from 74 to 523 ng g⁻¹ lw), DDTs (from 14 to 168 ng g⁻¹ lw) and chlordanes (from 9 to 78 ng g⁻¹ lw) were the prevailing compounds. Results showed a clear stratification in accordance with ecological data. Nonetheless, stable isotope analyses provide a deeper insight into fluctuations due to migrations and nutritional stress. Correlation between δ(15)N and pollutants suggests, to some degree, a considerable ability to metabolize and/or excrete the majority of them.


Assuntos
Caniformia/metabolismo , Monitoramento Ambiental , Poluentes Químicos da Água/metabolismo , Animais , Regiões Antárticas , Otárias/metabolismo , Éteres Difenil Halogenados/metabolismo , Hidrocarbonetos Clorados/metabolismo , Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Focas Verdadeiras/metabolismo , Poluição Química da Água/estatística & dados numéricos
6.
Chemosphere ; 85(3): 393-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21868055

RESUMO

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 (

Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Poluentes Químicos da Água/análise , Regiões Antárticas , Briófitas/química , Isótopos de Carbono/química , Caryophyllaceae/química , DDT/análise , Geografia , Éteres Difenil Halogenados/análise , Hexaclorobenzeno/análise , Líquens/química , Isótopos de Nitrogênio/química , Bifenilos Policlorados/análise
7.
Chemosphere ; 78(6): 767-71, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19917513

RESUMO

Polychlorinated biphenyls (PCBs) and organochlorine pesticides are compounds that do not occur naturally in the environment and are not easily degraded by chemical or microbiological action. In the present work, those compounds were analysed in unhatched penguin eggs and whole krill collected in Admiralty Bay, King George Island, Antarctica in the austral summers of 2004-2005 and 2005-2006. The compounds found in higher levels (in a wet weight basis) were, in most of the egg samples, the PCBs (2.53-78.7 ng g(-1)), DDTs (2.07-38.0 ng g(-1)) and HCB (4.99-39.1 ng g(-1)) and after Kruskal-Wallis ANOVA, the occurrence seemed to be species-specific for the Pygoscelis genus. In all of the cases, the levels found were not higher than the ones in Arctic birds in a similar trophic level. The krill samples analysis allowed estimating the biomagnification factors (which resulted in up to 363 for HCB, one order of magnitude higher than DDTs and chlordanes and two orders of magnitude higher than the other groups) of the compounds found in eggs, whose only source of contamination is the female-offspring transfer.


Assuntos
Hidrocarbonetos Clorados/análise , Óvulo/química , Resíduos de Praguicidas/análise , Spheniscidae , Animais , Regiões Antárticas
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