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Natural and anthropogenically-produced brominated compounds in endemic dolphins from Western South Atlantic: Another risk to a vulnerable species
2012
Alonso, Mariana B. | Eljarrat, Ethel | Gorga, Marina | Secchi, Eduardo R. | Bassoi, Manuela | Barbosa, Lupércio | Bertozzi, Carolina P. | Marigo, Juliana | Cremer, Marta | Domit, Camila | Azevedo, Alexandre F. | Dorneles, Paulo R. | Torres, João Paulo M. | Lailson-Brito, José | Malm, Olaf | Barceló, Damià
Liver samples from 53 Franciscana dolphins along the Brazilian coast were analyzed for organobrominated compounds. Target substances included the following anthropogenic pollutants: polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), decabromodiphenylethane (DBDPE), as well as the naturally-generated methoxylated-PBDEs (MeO-PBDEs). PBDE concentrations ranged from 6 to 1797 ng/g lw (mean 166 ± 298 ng/g lw) and were similar to those observed in cetaceans from Northern Hemisphere. PBBs were found in all sampling locations (<LOQ to 57 ng/g lw). DBDPE was detected in 42% of the dolphins from the most industrialized Brazilian state and the concentrations ranging from <LOQ to 352 ng/g lw. Franciscana dolphins from the tropical Brazilian shore presented the highest MeO-PBDE concentrations ever reported for coastal cetaceans (up to 14 μg/g lw). Eight MeO-PBDE congeners were detected and the present investigation constituted the first record of occurrence of six of them in marine mammal livers.
Afficher plus [+] Moins [-]DNA-damage effect of polycyclic aromatic hydrocarbons from urban area, evaluated in lung fibroblast cultures
2012
Teixeira, Elba Calesso | Pra, Daniel | Idalgo, Daniele | Henriques, João Antonio Pêgas | Wiegand, Flavio
This study was designed to biomonitor the effect of PAH extracts from urban areas on the DNA of lung cell cultures. The analyses of the polycyclic aromatic hydrocarbons (PAHs) were performed in atmospheric PM₂.₅ and PM₁₀ collected at three sampling sites with heavy traffic located in the Metropolitan Area of Porto Alegre (MAPA) (Brazil). The concentrations of 16 major PAHs were determined according to EPA. Comet assay on V79 hamster lung cells was chosen for genotoxicity evaluation. Temperature, humidity, and wind speed were recorded. With regard to the damage index, higher levels were reported in the extract of particulate matter samples from the MAPA during the summer. High molecular weight compounds showed correlation with DNA damage frequency and their respective carcinogenicity.
Afficher plus [+] Moins [-]Litterfall mercury deposition in Atlantic forest ecosystem from SE – Brazil
2012
Teixeira, Daniel C. | Montezuma, Rita C. | Oliveira, Rogério R. | Silva-Filho, Emmanoel V.
Litterfall is believed to be the major flux of Hg to soils in forested landscapes, yet much less is known about this input on tropical environment. The Hg litterfall flux was measured during one year in Atlantic Forest fragment, located within Rio de Janeiro urban perimeter, in the Southeastern region of Brazil. The results indicated a mean annual Hg concentration of 238 ± 52 ng g⁻¹ and a total annual Hg deposition of 184 ± 8.2 μg m⁻² y⁻¹. The negative correlation observed between rain precipitation and Hg concentrations is probably related to the higher photosynthetic activity observed during summer. The total Hg concentration in leaves from the most abundant species varied from 60 to 215 ng g⁻¹. Hg concentration showed a positive correlation with stomatal and trichomes densities. These characteristics support the hypothesis that Tropical Forest is an efficient mercury sink and litter plays a key role in Hg dynamics.
Afficher plus [+] Moins [-]Influence of sugarcane burning on indoor/outdoor PAH air pollution in Brazil
2012
Cristale, Joyce | Silva, Flávio Soares | Zocolo, Guilherme Julião | Marchi, Mary Rosa Rodrigues
This work presents the influence of sugarcane burning on PAH levels and their profiles at a residence located in Araraquara (SP, Brazil), a city surrounded by sugarcane plantations. The average concentrations of total PAHs (ΣPAHs) associated with atmospheric particulate matter were higher during the burning period (ΣPAHs 22.9 ng m⁻³) than in the non-burning period (ΣPAH 2.35 ng m⁻³). A comparison of our results with previous studies regarding PAH levels and their profiles in Araraquara outdoor air indicated that sugarcane burning was the main PAH air source in the indoor harvesting season samples. The benzo[a]pyrene equivalent (BaPₑq) was used for cancer risk assessment, and higher average values were obtained in the harvesting season air samples (1.7 ng m⁻³) than in the non-harvesting air samples (0.07 ng m⁻³). These findings suggest that sugarcane burning during the harvesting season can represent a public health risk in affected cities.
Afficher plus [+] Moins [-]PCBs, PBDEs and organochlorine pesticides in crabs Hepatus pudibundus and Callinectes danae from Santos Bay, State of São Paulo, Brazil
2012
Magalhães, C.A. | Taniguchi, S. | Cascaes, M.J. | Montone, R.C.
The occurrence of persistent organic pollutants (POPs) as polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDE) in crabs Hepatus pudibundus and Callinectesdanae was assessed from two different places inside of the Santos Bay and Moela Island near one of the most economically important metropolitan areas in Southern Brazil. Among POPs analyzed, ∑PCBs (222–923ngg⁻¹lipid weight) and ∑DDTs (154–410ngg⁻¹lw) exhibited the highest concentrations in the crabs. ∑HCHs ranged from 10.3 to 30.9ngg⁻¹lw and were found in all individuals. Other OCPs found in lower concentration was Mirex (7.6–41.6ngg⁻¹lw) and HCB (5.83–16.9ngg⁻¹lw). ∑PBDEs (24.1ngg⁻¹lw) were only found in one male individual from the species C. danae collected near to the submarine sewage of Santos. Male crabs showed higher POP concentrations than female crabs for those two species.
Afficher plus [+] Moins [-]Survival and movements of Magellanic penguins rehabilitated from oil fouling along the coast of South America, 2000–2010
2012
Ruoppolo, Valeria | Vanstreels, Ralph Eric Thijl | Woehler, E. J. (Eric J.) | Heredia, Sergio Andres Rodríguez | Adornes, Andréa Corrado | Silva-Filho, Rodolfo Pinho da | Matus, Ricardo | Poleschi, Carla | Griot, Karen | Kolesnikovas, Cristiane K Miyaji | Serafini, Patrícia
Oil pollution is a significant conservation concern. We examined data from six institutions along the coast of South America: Emergency Relief Team of the International Fund for Animal Welfare, Fundación Mundo Marino, Centro de Recuperação de Animais Marinhos, Natura Patagonia, Associação R3 Animal, and Mar del Plata Aquarium and data from resightings in Argentina, Brazil, Chile and Falkland/Malvinas Islands. From 2000 to 2010, 2183 oiled Magellanic penguins were rehabilitated as part of the routine activities of these institutions or during emergency responses to eight oil spills in which they were involved; all rehabilitated penguins were flipper banded and released. Since their release, 41 penguins were resighted until 31 December 2011. The results demonstrate that, when combined with other prevention strategies, the rehabilitation of Magellanic penguins is a strategy that contributes to the mitigation of adverse effects of oil spills and chronic pollution to the species.
Afficher plus [+] Moins [-]Levels and spatial distribution of trace elements in macroalgae species from the Todos os Santos Bay, Bahia, Brazil
2012
Brito, Geysa B. | de Souza, Thaís L. | Bressy, Fernanda C. | Moura, Carlos W.N. | Korn, Maria Graças A.
Concentrations of elements (As, Ba, Cd, Co, Cr, Cu, Li, Mn, Ni, Pb, V, and Zn) were determined in ten species of macroalgae collected from six sites in the Todos os Santos Bay, Brazil, between May and July of 2010. An optimized microwave-assisted digestion procedure was used to digest the samples. The elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). A wide range of metal concentrations were observed between the species analysed. Somewhat higher concentrations of Cd (5.99μgg⁻¹), Co (372μgg⁻¹), Mn (640μgg⁻¹), Ni (17.2μgg⁻¹) and Zn (51.4μgg⁻¹) were found in the brown macroalgae species Padina spp., whereas elements, such as As (19.7μgg⁻¹) and Pb (8.27μgg⁻¹), were mainly concentrated in the species Sargassum spp. and Bostrychia montagnei, respectively. Statistical analyses (ANOVA) of the Padina data showed significant inter-site differences for all metals examined except nickel.
Afficher plus [+] Moins [-]Benthic foraminifera as proxies of pollution: The case of Guanabara Bay (Brazil)
2012
Donnici, Sandra | Serandrei-Barbero, Rossana | Bonardi, Maurizio | Sperle, Marcelo
Due to economic importance of Guanabara Bay, a multidisciplinary approach was adopted to investigate 88 surficial sediment samples in order to use the benthic foraminifera as indicators for the characterization of environmental variations. Grain-size analyses indicate that bottom sediments of the inner part of the bay are mainly muddy while those close to the entrance of the bay are sandy. Geochemical data show high concentration of heavy metals mainly in the northern region of the bay. Micropalaeontological analyses indicate the boundaries of the areas with the highest concentration of heavy metals. The dominant benthic foraminifera in the bay are Ammonia beccarii and Buliminella elegantissima, taxa capable of differentiating the presence of pollutants of different sources. B. elegantissima, in particular, has shown to be an indicator of anthropogenic pollution. The study highlights the worsening of environmental conditions since 2000 and those areas of the bay in need of a priority recovery.
Afficher plus [+] Moins [-]Seasonal variation of polycyclic aromatic hydrocarbons concentrations in urban streams at Niterói City, RJ, Brazil
2012
Ribeiro, Angelo Morgado | da Rocha, Camila Coimbra Martins | Franco, Caroline Fernandes Jaegger | Fontana, Luiz Francisco | Pereira Netto, Annibal D.
Polycyclic aromatic hydrocarbons (PAHs) were determined in water samples collected in two streams and a lake located at Niteroi City, Rio de Janeiro State, Brazil between October 2008 and September 2009. Samples were extracted using liquid–liquid extraction and analyzed using high performance liquid chromatography with fluorescence detection. The limits of quantification were sufficiently low to accomplish PAH determination below the maximum concentration levels established by the Brazilian (50ng/L) and USEPA legislations, with recoveries larger than 81.6%. Phenanthrene, fluoranthene, pyrene and benz[a]anthracene predominated among PAHs. Total concentrations of PAHs were well correlated with rainfall indicating a possible role of runoff to local pollution of water by PAHs and showed a seasonal variation in wet and dry seasons. Our results highlight the contribution of the widespread streams located around Guanabara Bay to the PAH burden found in its waters.
Afficher plus [+] Moins [-]Molecular and biochemical biomarkers responses in the mussel Mytilus edulis collected from Southern Brazil coast
2012
Rola, Regina Coimbra | Monteiro, Maurício da Costa | Reis, Sérgio Renan da Silva | Sandrini, Juliana Zomer
Marine ecosystems are typically subjected to a variety of stressors containing complex xenobiotics mixtures. This study aims to evaluate the responses of molecular and biochemical biomarkers in the mussel Mytilus edulis providing data for environmental monitoring programs development in Southern Brazil. Mussels were collected at a polluted site, near Patos Lagoon outfall, and at a control site. Gills, muscle and mantle samples were used for biomarker determinations. Mussels collected at the polluted site significantly increased superoxide dismutase (SOD) and glutathione S-transferase (GST) activities and decreased catalase (CAT) activity. Moreover, an increase in sod1, gstπ and hsp70 mRNA expression was observed. Overall, biochemical and molecular biomarkers responses were observed, but these responses varied depending on the analyzed tissue. These results indicate possible contaminants effects on organisms and the need for effective environmental monitoring programs in this ecosystem.
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