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1.
Biol Trace Elem Res ; 202(5): 2272-2278, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37542592

RESUMO

This study investigated the feathers' composition of South polar skua (Stercorarius maccormicki) using WDXRF, evaluating the concentration of essential and non-essential elements in the feathers, and dividing it into rachis and barb parts. We collected South polar skuas feathers from Hennequin Point, King George Island, South Shetland, Antarctic Peninsula in January of 2013. Our results show that 18 elements were observed in the composition of the feathers, with a different concentration between the rachis and barbs, qualitatively and quantitatively. Only 3 elements observed were classified as non-essentials but still mostly elements do not have a function described in the literature to the feathers. According to our knowledge, this is the first study that uses this technique to evaluate the concentration of different elements in the feathers. The findings of this study highlight the use of alternative techniques to biomonitoring elements in the ecosystem and bring baseline information for future studies.


Assuntos
Charadriiformes , Ecossistema , Animais , Plumas , Regiões Antárticas , Monitoramento Biológico
2.
Environ Pollut ; 284: 117209, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33932832

RESUMO

Contaminant levels are lower in Antarctica than elsewhere in the world because of its low anthropogenic activities. However, the northern region of the Antarctic Peninsula, is close to South America and experiences the greatest anthropogenic pressure in Antarctica. Here, we investigated, in two Antarctic Peninsula islands, intra and interspecific factors that influence the concentrations of 17 trace elements (TEs) in blood and feathers of three penguin species breeding sympatrically in relation to their trophic ecology assessed via a stable isotopic approach (C, N and S). Geographical location, foraging zone (δ13C and δ34S) and diet influences the interspecific difference, and sex and maturity stage diet influence the intraspecific difference of Pygoscelis penguins. Penguins from Livingston showed higher values (mean, ng. g-1, dry weight - dw) of Zn (103), Mn (0.3), and Fe (95) than those from King George Island (Zn: 80, Mn: 1.9, and Fe: 11). Gender-related differences were observed, as males showed significantly higher values (mean, ng. g-1, dw) of Rb (3.4) and δ15N in blood of gentoo, and Ca (1344) in Adélie feathers. Chicks of gentoo and Adélie presented higher Zn, Mg, Ca, and Sr and lower 13C values in blood than adults. The highest concentrations (mean, ng. g-1, dw) of Cd (0.2) and Cu (26), and the lowest δ15N values were found in chinstrap. Geographical, intraspecific (i.e., ontogenetic and gender-related) and interspecific differences in feeding seemed to have influenced TE and stable isotope values in these animals. The TE bioaccumulation by penguins may have also been influenced by natural enrichment in environmental levels of these elements, which seems to be the case for Fe, Zn, and Mn. However, the high level of some of the TEs (Mn, Cd, and Cr) may reflect the increase of local and global human activities.


Assuntos
Spheniscidae , Oligoelementos , Animais , Regiões Antárticas , Plumas/química , Humanos , Ilhas , Masculino , América do Sul , Oligoelementos/análise
3.
Biodegradation ; 31(4-6): 235-247, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32676947

RESUMO

Biomats that flourished in a fumarole located on the geothermal site Los Azufres (Mexico) were used as inocula to select aerobic and sulfate-reducing bacteria consortia for studying their capacity to reduce hexavalent chromium [Cr(VI)], aiming to use these consortia in biotransformation technologies. The sample site is characterized by slightly warm (nearly 27 [Formula: see text]C), acid (pH 3) and about hypoxic (1.8 mg L[Formula: see text] of dissolved oxygen) conditions. Four culture systems (2 aerobic and 2 anaerobic) were investigated, including their enzymatic activity, capacity to produce biofilms, and an analysis of the total bacterial populations. For the anaerobic condition (using sulfate and sulfur as electron acceptors), four pH values (from 2 to 8) and four carbon sources (pyruvate, glycerol, Na-lactate and Na-acetate) were probed. Significant biological Cr(VI) removal was observed for all the pH values probed, particularly during the first 12 h, being more effective at the most acid conditions. At a pH value of 4 and using pyruvate as carbon source, 100 mg L[Formula: see text] of Cr(VI) were completely depleted in less than 12 h, while the use of Na-lactate was less effective but still reasonable. These results indicate that sulfate-reducing bacteria consortia from geothermal sites like the one studied here are capable of biotransforming Cr(VI) and have the potential to provide metal bioremediation technologies.


Assuntos
Bactérias , Cromo , Biodegradação Ambiental , Biotransformação , Oxirredução , Sulfatos
4.
Environ Pollut ; 242(Pt A): 684-691, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30025342

RESUMO

Natural compounds from the metabolism of marine organisms have been detected at high concentrations in environmental samples which are not the producers of these compounds. These natural substances are known as halogenated natural products (HNPs). HNPs are possibly toxic halogenated compounds analogous to POPs that may bioaccumulate and biomagnify along the food web and pose a further risk to human and environmental health. The present study analyzed the occurrence of HNPs in the edible muscle of the three most consumed commercial fish species in the state of Rio de Janeiro: sardine (Sardinella brasiliensis), whitemouth croaker (Micropogonias furnieri) and mullet (Mugil liza) from the highly polluted Guanabara Bay (GB) and the less polluted Ilha Grande Bay (IGB). The analytical steps included Soxhlet extraction, clean-up step and injection in a gas chromatography system coupled to a mass spectrometer operated in the electron-capture negative ion mode (GC/ECNI-MS). The compounds 2,4,6-TBP, 2,4,6-TBA, MHC-1, Q1, 6-MeO-BDE 47 and 2'-MeO-BDE 68 were found in the analyzed fish from both studied areas. Q1, 6-MeO-BDE 47 and 2'-MeO-BDE 68 showed the highest concentrations in samples. Q1 concentrations in the sardines from IGB were higher than the sardines from GB (p < 0.05) and higher than the other IGB species (p < 0.05). The differences found among the species may be related to their characteristic habitat and diet. It is noteworthy that most of these compounds do not have any toxicological reference value. Moreover, the HNPs are being detected in species of low trophic level and since this study has worked only with commercial species, these fish may be considered as a source for human exposure to these natural compounds.


Assuntos
Baías , Produtos Biológicos/análise , Músculos/química , Animais , Brasil , Monitoramento Ambiental , Poluição Ambiental/análise , Peixes/metabolismo , Cadeia Alimentar , Halogenação , Poluentes Químicos da Água/análise
5.
J Trace Elem Med Biol ; 34: 50-5, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26854245

RESUMO

This work aimed to investigate metal bioaccumulation by mussels (Perna perna) and Lion's Scallop (Nodipecten nodosus) farmed in tropical bays, in order to estimate spatial and temporal variation in the exposure to these elements, as well as human health risk. The concentration of each measured element was considered for this evaluation, using maximum residue level (MRL) in foods established by the Brazilian (ANVISA), American (USFDA) and European Communities (EC) legislations. Values for estimated daily ingestion (EDI) were determined for metals intake through mussel and scallop consumption. These estimates were compared with the reference value of (PTDI) proposed by World Health Organization (WHO). Trace elements concentration was measured on ninety mussels P. perna (tissue) and ninety Lion's Scallop N. nodosus (muscle and gonad) reared in four different tropical areas of the Southeast Brazilian coast, between 2009 and 2010. Zinc (Zn), Iron (Fe), Copper (Cu), Manganese (Mn), Chrome (Cr), Nickel (Ni), Cadmium (Cd) and Lead (Pb) concentrations were measured by flame atomic absorption spectrometry after acid mineralization. Cd and Mn were more efficiently bioaccumulated by scallops than mussels and the opposite was found for Fe, Cu and Ni. Guanabara Bay and Sepetiba Bay were considered the most impacted between ecosystems studied. Higher Cd values in Arraial do Cabo in the other sites studied were associated with upwelling that occurs in the region. Consumption of both species cannot be considered safe, because the Cu and Cr concentrations, in accordance with the limits established by the Brazilian Agency (ANVISA). On the other hand, any EDI value exceeded the corresponding value of the PTDI, proposed by World Health Organization (WHO).


Assuntos
Bivalves/metabolismo , Metais/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Brasil , Cádmio/análise , Cádmio/metabolismo , Cromo/análise , Cromo/metabolismo , Cobre/análise , Cobre/metabolismo , Monitoramento Ambiental , Metais/análise , Poluentes Químicos da Água/análise
6.
Environ Sci Pollut Res Int ; 20(4): 1951-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22825640

RESUMO

Hexachlorocyclohexane (HCH) isomers (α-, ß- and γ- HCH [lindane]) were recently added to the list of persistent organic pollutants regulated by the Stockholm Convention, and therefore, the legacy of HCH and lindane production has become an issue of global relevance. The production of lindane with the much larger quantities of associated waste isomers has generated large waste deposits and contaminated sites. This article presents an overview of HCH-polluted sites in Brazil as a basis for further activities related to the Stockholm Convention. The locations of HCH stockpiles and contaminated sites in Brazil arising from production and formulation have been compiled and mapped. This shows that the measures taken over the past 25 years have not resulted in remediation of the HCH pollution. An exposure risk study has been summarised for one major site and is included to demonstrate the contemporary relevance of the contamination. Major site remediation efforts are planned at one site but people live close to several other sites, and there is an urgent need of further assessments and remediation to ensure the protection of human health and the environment. The Stockholm Convention requires a systematic approach and should be adopted for the assessment of all sites and appropriate isolation/remediation measures should be facilitated. The appropriate planning of these activities for the production site in Rio de Janeiro could be a positive contribution for Rio+20 highlighting that green economy and sustainable production also include the appropriate management of legacies of historic production of an industrial sector (here the organochlorine industry).


Assuntos
Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Resíduos Perigosos/análise , Hexaclorocicloexano/análise , Resíduos Industriais/análise , Resíduos de Praguicidas/análise , Brasil , Política Ambiental , Recuperação e Remediação Ambiental/legislação & jurisprudência , Medição de Risco
7.
Environ Sci Technol ; 46(22): 12364-72, 2012 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-23016984

RESUMO

Concentrations of Dechlorane (Dec) 603 (0.75 ng/g lipid weight (lw); mean) and Dec 602 (0.38 ng/g lw; mean) were quantified in more than 95% of the franciscana (Pontoporia blainvillei) dolphin samples, whereas the frequency of detection decreased to 75% for Dechlorane Plus (DP) (1.53 ng/g lw, mean). The presence of Chlordene Plus (CP) was also observed (0.13 ng/g lw, mean) in half of the samples. On the contrary, Dec 604, decachloropentacyclooctadecadiene (aCl(10)DP), and undecachloropentacyclooctadecadiene (aCl(11)DP) concentrations were below the limit of quantifications in all cases. To the best of our knowledge, this is the first article reporting the presence of Dec 603, Dec 602, and CP in mammals. For comparative purposes, levels of Mirex, polybrominated diphenyl ethers (PBDEs), and decabromodiphenylethane (DBDPE) are also reported. Considering geographic distribution evaluation together with the strong positive correlations found between DP and PBDEs (r(s) = 0.63; p < 0.01), highly anthropogenic areas were identified as potential sources of these chemicals in this dolphin species. However, local sources for Dec 602, 603, Mirex, CP, and DBDPE were not found indicating that in this case historical use and/or atmospheric transport and deposition may play an important role in their fate.


Assuntos
Bromobenzenos/metabolismo , Exposição Ambiental , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/metabolismo , Hidrocarbonetos Clorados/metabolismo , Poluentes Químicos da Água/metabolismo , Fatores Etários , Animais , Brasil , Cromatografia Gasosa , Monitoramento Ambiental , Geografia , Espectrometria de Massas , Fatores Sexuais
8.
Chemosphere ; 87(9): 1039-44, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22391047

RESUMO

This study aimed to investigate the impact of contamination by persistent organic pollutants (POPs) on Brazilian wildlife. The concentrations of certain POPs, including dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCBs), in the eggs of the brown booby (Sula leucogaster) were measured. The eggs were collected from breeding colonies located on three archipelagos (Saint Peter and Saint Paul, Abrolhos and Cagarras Islands) in the Atlantic Ocean, which are located at different distances from the Brazilian coast (range 4-1010 km). In addition, possible alterations in eggshell characteristics were evaluated. The average values of POPs found in eggs from the archipelago of Saint Peter and Saint Paul (0.05µgg(-1) of ΣPCBs and 0.01 µg g(-1) of ΣDDT) and the archipelago of Abrolhos (0.19 µg g(-1) of ΣPCBs and 0.03 µg g(-1) of ΣDDT) were low compared to the reference values reported in the literature. In contrast, the concentrations measured in eggs from Cagarras (8.4 µg g(-1) of ΣPCBs and 1.8 µg g(-1) of ΣDDT) were the highest, and this total PCB level is close to the threshold values considered to be harmful to birds. Our findings indicate that the brown booby colony closest to the Rio de Janeiro coast has recently been exposed to DDT. Despite the high pollution levels found on the Cagarras Islands, no alterations in the eggshell weight or the thickness of the analyzed eggs were detected. Hence, more detailed studies are recommended to determine the actual effects of the selected POPs on the Cagarras breeding colony.


Assuntos
Aves , Poluentes Ambientais/análise , Poluentes Ambientais/toxicidade , Óvulo/química , Animais , Oceano Atlântico , Brasil , DDT/análise , Casca de Ovo/química , Feminino , Tamanho do Órgão/efeitos dos fármacos , Bifenilos Policlorados/análise
9.
Environ Pollut ; 158(5): 1800-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19932538

RESUMO

Blubber samples from 33 Guiana dolphins (Sotalia guianensis) from three estuaries (Guanabara, Sepetiba/Ilha Grande and Paranaguá Bays) of Southern and Southeastern Brazil were analyzed for organochlorine compounds (DDTs, PCBs and HCB). The sampled individuals were incidentally captured in gillnet fishery between 1995 and 2005. The concentrations (in ng/g lipids) varied from 652 to 23 555 for SigmaDDT; from 765 to 99 175 for SigmaPCB; and from <4.4 to 156 for HCB. The results have shown that cetaceans from Brazil present organochlorine concentrations that are comparable to those reported for highly industrialized regions of Northern Hemisphere. Using discriminant analysis it was possible to verify that the dolphin populations from the three bays present different organochlorine accumulation patterns. This feature allows the use of this set of pollutants as an auxiliary tool for identification of different populations of the species off Brazilian Coast.


Assuntos
Tecido Adiposo/química , Golfinhos/classificação , Golfinhos/metabolismo , Hidrocarbonetos Clorados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Brasil , Bifenilos Policlorados/metabolismo , Água do Mar/análise
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