Food Safety in Amazon : potential mercury contamination of preferred fish in the Tapajós river

Abstract

Methylmercury (MeHg) is a persistent bioaccumulative toxic metal, verified in tropical river-floodplain systems and it is recognized as a major environmental pollution issue and health hazard for humans. Tapajós River (Brazil), one of the major tributaries of the Amazon has been impacted by traditional gold mining from the mid-1980s and largely deforested, which causes its water to be highly contaminated with mercury. The riverine populations consume native fish from Tapajós river, which sets a potential health risk due to mercury toxicity to the nervous, digestive and immune systems, lungs and kidneys. This paper presents an association between the most captured fish in Tapajós downstream regions, mercury contamination and consumption safety. We used mercury contamination data from literature, in addition to interviews with fishermen conducted on sixteen riverine communities along Tapajós. Fiftyfour and eight percent of the evaluated fish demonstrated low Hg levels, 40.76% demonstrated high levels of Hg and 4.88% had no data available.