Assessment of DDT and mercury levels in fish and sediments in the Iriri River, Brazil: distribution and ecological risk

• Autor(a) principal: Mendes, Rosivaldo A
• Data de Publicação: 2019
• Outros Autores: Lima, Marcelo de Oliveira, Deus, Ricardo J. A. de, Medeiros, Adaelson Campelo, Faial, Kelson do Carmo Freitas, Jesus, Iracina Maura de, Faial, Kleber Raimundo Freitas, Santos, Lourivaldo S
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Digital do Instituto Evandro Chagas (Patuá)
• Texto Completo: https://patua.iec.gov.br/handle/iec/3867
• topic: Poluição Ambiental / análise; DDT / envenenamento; Intoxicação por Mercúrio; Peixes / anatomia & histologia; Monitoramento Ambiental; Sedimentos / análise; Rio Iriri (PA)

In order to assess the risk of exposure of human populations to dichlorodiphenyltrichloroethane (DDT) and mercury, muscles of five fish species were analysed, along with the surface sediment of 14 Iriri River sampling sites. The fish specimens were sacrificed by the spinal section, prior to sex identification, body weight determination and total length. Considering the fish specimens studied, 11% of them showed concentrations of mercury higher than the maximum established by the World Health Organization for safe human consumption. A positive correlation between fish body weight and mercury concentration was observed, besides a positive correlation between the fish size and Hg concentration. Significant differences (P < 0.05) were found between mean concentrations of DDT and metabolites among species of fish studied. In the Plagioscion squamossissimus species, the highest concentration of total DDT (151.4 ng/g) was found, while in Eugerres Brasilianus species, the lowest. However, the DDT levels in fish muscle of studied species are below the maximum set by FAO-Alimentarius CODEX. In the sediments, total DDT ranged from 11.58 ng/g to 48.4 ng/g, which is associated with the historical DDT use in the Amazon. According to sediment quality guidelines, these levels have a moderate toxic effect in almost all of the studied region.