Zinc, Copper and Iron in Consumed Fish from Tapajós River Basin, PA, Brazil

Nowadays, a wide range of ecosystems are under anthropogenic disturbance. Aquatic organisms are exposed to a large number of toxic substances and can be used for environmental monitoring. Zinc, copper and iron are essential metals, however, in high concentrations have toxic effects. This study investigated the concentration of these elements in fish muscle from Tapajos river basin to estimate human exposure and its spatial variation along the Tapajos river. Fish (n = 129) from four areas along 400 km of the Tapajos river (Bubure, Itaituba, Alter do Chao and Santarem) were assessed. Metal concentrations were measured by flame atomic absorption spectrometry after acid mineralization. Zinc, copper and iron concentrations in fish ranged from 2 to 15 [micro]g x [g.sup.-1] wet weight (w.w.), 1 to 4 [micro]g x [g.sup.-1] w.w. and 5 to 286 [micro]g x [g.sup.-1] w.w., respectively. The concentrations of these elements were below the maximum residue level permitted in food established by the Brazilian legislations (ANVISA). The estimated daily ingestion values of the three elements did not exceed the reference value proposed by World Health Organization based on a diet composed of these fish species. Zinc, copper and iron are essentials, therefore, there is also a recommendation of the minimum daily ingestion to avoid deficiency. Considering a daily consumption of 200 g of these fish, the population no reaches of the recommended minimum value of these elements.