Environmental disaster in mining areas: routes of exposure to metals in the Doce River basin

On November 5, 2015, the greatest environmental disaster in Brazil occurred due to the rupture of the Fundao dam, contaminating the Doce River basin. In this case, the present work aims to determine the concentrations of Al, As, Ba, Cd, Co, Cu, Cr, Fe, Mn, Ni, Pb, Se, Zn in the mud in Governador Valadares city, in the gills and muscle tissue of the fish from the Doce River in Santo Antonio do Rio Doce and Ilha das Pimentas, determine the daily intake estimate and evaluate the frequency of micronuclei and nuclear abnormalities in fish erythrocytes. Three samples of mud, seven samples of water and 75 fish were collected, with analysis by inductively coupled plasma mass spectrometry. The results show that the mud and water present parameters within the established values, meeting the low percentage of micronuclei and nuclear abnormalities. The gills present results of greater bioaccumulation compared to the musculature of the fish in the elements Al, Ba, Cr, Fe, Mn, Se and Zn. In muscle tissue, Fe and Se had high concentrations; however, in the daily estimate calculation, it did not present a health risk when considering the highest consumption rated. The present data suggest that there is no risk of fish consumption in daily portions of 60 g in these locations. The mud and water of the Doce River do not present altered concentrations of chemical elements, but the bioaccumulation of elements in the gills of fish suggests an indicator of environmental pollution.

Automated summary

This study investigated the concentrations of chemical elements in mud, fish, and water samples from Governador Valadares city in Brazil after a major environmental disaster. The results showed that the gills of fish had higher bioaccumulation of elements compared to muscle tissue, and the daily intake of fish in these locations did not pose health risks. Therefore, it suggests that fish consumption of 60 grams per day in these areas is safe.