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For assessing the impact of chlorinated compounds, such as organochlorine pesticides, polychlorinated biphenyls, chlorotriazines (atrazine, simazine), and chlorinated phenylureas (diuron), on the Ponta Grossa lake South of Brazil, ten freshwater trahira fish (Hoplias malabaricus) were collected in October 2005. The contamination status was evaluated by the energy budget and various histopathological markers. The results showed detectable amounts of persistent organic pollutants (POPs) in the liver and muscle; the bioaccumulation was higher in the liver than in the muscle. The presence of some banned pesticides, such as hexachlorobenzene and dichlorodiphenyltrichloroethane, in the liver suggests an acute exposure to these compounds. Some physiological disturbances and morphological damages found in the liver of H. malabaricus were associated with chlorinated-compound bioaccumulation. The most important alterations in the liver were lesions such as fibrosis, large necrosis area, leukocyte infiltration, and the absence of melanomacrophages (MM). Individuals containing higher concentrations of pesticides, such as aldrin, alachlor, and dichloroaniline (a metabolite of diuron), showed the nonoccurrence of MM in the liver. These data suggest an immunosuppression in the individuals from Ponta Grossa Lake after exposure to POPs. According to the present data, the POPs found in the studied site are bioavailable, induce severe damages in target organs such as the liver, and can disturb the immune system of the trahira. This is the first study of POPs in the Paraná state, and one among the few studies in the south of Brazil. The present data suggest and motivate further chemical and biomonitoring studies in freshwater ecosystems in the south of Brazil. 相似文献
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Variation of nutrient and metal concentrations in aquatic macrophytes along the Rio Cachoeira in Bahia (Brazil) 总被引:6,自引:0,他引:6
The use of cuprous fungicides in cocoa production in the southern part of the state of Bahia (Brazil) for decades has caused an accumulation of copper in various components of the cocoa plantations, and a contamination of regional freshwater ecosystems is suspected. Urban and industrial sources are supposed to contribute to water pollution and eutrophication of the Rio Cachoeira, the main river in this region. In order to study the metal contamination and nutritional status of this freshwater ecosystem, samples of the aquatic macrophytes Eichhornia crassipes and Pistia stratiotes were collected at seven sites along the river course. The samples were analysed for their copper, aluminium, chromium, nitrogen and phosphorus concentrations. The levels of heavy metals increased in the downstream direction, particularly in the roots of water hyacinth. A dramatic increase of nitrogen and phosphorus concentrations in water as well as in plant tissues was found in samples collected downstream from the city of Itabuna. Metal input and eutrophication were attributed to agricultural, industrial and urban sources in the region. Biomonitoring of the water quality using aquatic macrophytes as accumulative indicator plants is recommended in addition to chemical water analyses. 相似文献
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Vieira CD de Carvalho MA Cussiol NA Alvarez-Leite ME dos Santos SG Gomes RM Silva MX Nicoli JR Farias Lde M 《Waste management (New York, N.Y.)》2011,31(6):1327-1332
In Brazil, few studies on microbial content of dental solid waste and its antibiotic susceptibility are available. An effort has been made through this study to evaluate the hazardous status of dental solid waste, keeping in mind its possible role in cross-infection chain. Six samples of solid waste were collected at different times and seasons from three dental health services. The microbial content was evaluated in different culture media and atmospheric conditions, and the isolates were submitted to antibiotic susceptibility testing. A total of 766 bacterial strains were isolated and identified during the study period. Gram-positive cocci were the most frequent morphotype isolated (48.0%), followed by Gram-negative rods (46.2%), Gram-positive rods (5.0%), Gram-negative-cocci (0.4%), and Gram-positive coccobacillus (0.1%). Only two anaerobic bacteria were isolated (0.3%). The most frequently isolated species was Staphylococcus epidermidis (29.9%), followed by Stenotrophomonas maltophilia (8.2%), and Enterococcus faecalis (6.7%). High resistance rate to ampicillin was observed among Gram-negative rods (59.4%) and Gram-positive cocci (44.4%). For Gram-negative rods, high resistance was also noted to aztreonam (47.7%), cefotaxime (47.4%), ceftriaxone and cefazolin (43.7%), and ticarcillin-clavulanic acid (38.2%). Against Gram-positive cocci penicillin exhibit a higher resistance rate (45.0%), followed by ampicillin, erythromycin (27.2%), and tetracycline (22.0%). The present study demonstrated that several pathogenic bacteria are present in dental solid waste and can survive after 48 h from the waste generation time and harbor resistance profiles against several clinical recommended antibiotics. 相似文献
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Moraes BS Loro VL Glusczak L Pretto A Menezes C Marchezan E de Oliveira Machado S 《Chemosphere》2007,68(8):1597-1601
Effects of different herbicides on acetylcholinesterase (AChE), catalase and TBARS formation in teleost fish (Leporinus obtusidens) were studied. Fish were exposed during 30 days at concentrations of herbicides used in rice field. AChE activity in the brain decreased significantly after exposure to the herbicides clomazone and quinclorac. However, AChE activity increased significantly in muscle tissue after exposure to clomazone, propanil and metsulfuron methyl. Fish exposed to quinclorac, propanil and metsulfuron methyl showed TBARS decreased levels in brain and muscle tissues. However, TBARS and catalase activity increased in liver tissue after clomazone and propanil exposure. This study pointed out long-term effects on AChE activity, oxidative stress and antioxidant enzyme catalase in tissues of L. obtusidens after exposure to environmentally relevant concentrations of rice field herbicides. These parameters have been used to monitor fish toxicity in rice field system. 相似文献
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da Silva Joelma P. do S. Costa Maria Campina Fabia F. Bezerra Camila F. de Freitas Thiago S. Sousa Amanda K. Sobral Souza Celestina E. de Matos Yedda M. L. S. Pereira-Junior Francisco N. Menezes Irwim R. A. Coutinho Henrique D. M. Rocha Janaína E. 《Environmental geochemistry and health》2021,43(4):1609-1616
Environmental Geochemistry and Health - Mercury is widely found in nature, however, in low concentrations, but anthropological activities have increased its concentration considerably. This causes... 相似文献
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de Moraes Calado Sabrina Loise Salgado Lilian Dalago Santos Gustavo Souza da Silva Carvalho Neto Fernando de Menezes Márcia Santos 《Environmental science and pollution research international》2021,28(5):5283-5295
Environmental Science and Pollution Research - Metal contamination is a threat to estuarine environments. They can accumulate in the food chain and cause toxic effects on aquatic organisms and... 相似文献
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de Oliveira Maria Rayane Correia de Lima Silva Maria Gabriely Alcântara Isabel Sousa Filho Jaime Ribeiro Tintino Cícera Datiane de Morais Oliveira Magalhães Francisco Ernani Alves Martins Anita Oliveira Brito Pereira Bezerra Pessoa Renata Torres Duarte Antonia Eliene da Costa José Galberto Martins de Lima Sidney Gonçalo Coutinho Henrique Douglas Melo Capasso Raffaele de Menezes Irwin Rose Alencar 《Environment, Development and Sustainability》2021,23(10):14958-14981
Environment, Development and Sustainability - This work aimed to analyze the chemical composition and evaluate the anti-inflammatory and antinociceptive properties of the essential oil obtained... 相似文献
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Costa Maria Angélica Martins da Silva Bruno Menezes de Almeida Sâmilla Gabriella Coelho Felizardo Marcos Paulo Costa Ana Flávia Martins Cardoso Arnaldo Alves Dussán Kelly Johana 《Environmental science and pollution research international》2023,30(4):8835-8852
Environmental Science and Pollution Research - Energy demand has increased worldwide, and biomass burning is one of the solutions most used by industries, especially in countries that have a great... 相似文献
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Santana Antônio H. Araújo José A. S. Bento Amanda M. S. Santos Ana R. Santos Leocácia G. Gomes Hiago de O. da Costa José Galberto M. Menezes Jorge Marcell C. Coutinho Henrique Douglas Melo Filho Francisco José de P. Teixeira Raimundo Nonato P. 《Environmental geochemistry and health》2021,43(4):1583-1597
Environmental Geochemistry and Health - The contamination of bodies of water by potentially hazardous elements has in recent decades become an environmental problem that poses serious risks to... 相似文献