Aplicação de múltiplos biomarcadores em peixe neotropical para avaliação da contaminação aquática em áreas de influência agrícola e urbana.

• Autor(a) principal: Ghisi, Nédia de Castilhos
• Data de Publicação: 2013
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Estadual de Maringá (RI-UEM)
• Texto Completo: http://repositorio.uem.br:8080/jspui/handle/1/4961
• topic: Astyanax aff; paranae (Teleostei, Characidae) "lambari"; Biomarcadores; Contaminação aquática; Ecotoxicologia; Biomonitoramento; Efluentes urbanos; Estação de tratamento de esgoto; Pesticidas; Paraná (Estado); Brasil.; Biomarkers; Ecotoxicology; Biomonitoring; Urban Wastewaters; Sewage Treatment Plant; Pesticides; Paraná State; Brazil.; Ciências Biológicas; Ecologia

The purpose of this study was to assess through multibiomarkers the river condition in a subjected site to agricultural pollution, upstream of a city; a second site downstream of this city, subjected to urban, industrial and sewage plants effluents; and to compare them to a reference site in a Biological Reserve (Rebio). Fishes of Astyanax aff. paranae specie were used as bioindicators, sampled in July 2011 (winter) and November 2011 (summer). The piscine micronucleus test showed the highest alteration rate in Rebio during summer. Downstream site in both season showed high value in comparison with the lowest value found in Rebio winter. The upstream site show intermediated values. After that, the high damage rate was observed in downstream site during both seasons, followed in the upstream site. The comet assay with blood showed similar damage rate in anthropogenic sites, which are higher than that in Rebio. The comet assay with gill presented the lowest damage rate in Rebio on summer, being significantly smaller than the other sites. In comet assay with liver tissue were observed in Rebio summer the smallest DNA damage, followed by the damage seen in this same site in winter. To this biomarker, downstream site presented the highest DNA damage. The histopathological index of gill had the lowest value in Rebio and the highest in downstream. The main histological changes were lamellar fusion and hyperplasia, epithelium detachment, aneurysm and lamellar hypertrophy. The histopathological index of liver shows similar results to those observed by comet assay with blood. Among the more frequent hepatic alterations were observed vacuolization and melanomacrophages centers, moderated proportions of necrosis and some free melanomacrophages. In biochemical biomarkers, was observed a reduction in Gluthatione-S-Transferase activity in anthropogenic sites, with the smallest value in agricultural region. This enzyme also presented inhibition on summer when compared on winter. Catalase did not present a clear trend in enzymatic activity and lipoperoxidation was increased in downstream site during summer. The brain acetylcholinesterase has decreased on summer in anthropogenic sites relative to Rebio. The same trend was observed in muscle acetylcholinesterase. Summarizing the results, there was a general trend, with the highest changes in biomarkers in downstream site. It can be attributed to residential, urban and sewage treatment plan discharges. The upstream city site, surrounded by agricultural areas presented similar results to downstream, or intermediary to downstream and Rebio. The damages in this site can be attributed to pesticides used in crop farming.