Bioaccumulation of methylmercury in fish tissue from the Roosevelt River, Southwestern Amazon basin

• Autor(a) principal: Anjos,Marcelo Rodrigues dos
• Data de Publicação: 2016
• Outros Autores: Machado,Nadja Gomes, Silva,Maria Eliana Peixoto da, Bastos,Wanderley Rodrigues, Miranda,Márcio Rodrigues, Carvalho,Dario Pires de, Mussy,Marília Higino, Holanda,Igor Bruno Barbosa de, Biudes,Marcelo Sacardi, Fulan,João Ânderson
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Revista Ambiente & Água
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1980-993X2016000300508
• topic: biomagnification; chemical contamination; water pollution.

Abstract Mercury is a major pollutant in the Amazon River system, and its levels in fish and human hair are usually above the limit recommended by health agencies. The objective of this study was to analyze the methylmercury (MeHg) concentration in fish tissue from the Roosevelt River. The river's water velocity, depth, pH, temperature, electrical conductivity, dissolved oxygen and substrate type were measured, and fifty specimens distributed in 14 fish species were collected. A total of 64.3% of the sampled species were of the order Characiform and 71.4% of the species were carnivores. Fifty percent of the species had MeHg concentrations above threshold limit (Hg-T 0.5 mg kg-1) established for food by the World Health Organization. Cichla monoculus had the highest value of MeHg (2.45 mg kg-1). The MeHg concentration in fish varied according to dietary habits. The study also found bioaccumulation of MeHg in fish tissue in the following descending order: carnivorous > detritivorous > frugivore. Low significant correlations were found between fish weight or length and MeHg. Further studies on MeHg contamination are recommended in tissues of fish consumed in human riverine communities in the Roosevelt River Basin.