MERCURY EXPOSURE THROUGH FISH CONSUMPTION IN THE URBAN AREA OF ALTA-FLORESTA IN THE AMAZON BASIN

This work addresses the mercury exposure scenarios through fish consum ption in the urban area of Alta Floresta, by comparing the different p atterns of mercury exposure from fish ingestion for different populati on groups. This study was based on field surveys that could provide ba ckground information, such as the characteristics of Hg sources, chara cteristics of local and regional environment, Hg concentrations in dif ferent media, and the characterization of the local urban population. The urban area of Alta Floresta is one of the most important gold-trad ing centers in Amazonia, where approximately 1 ton of gold has been co mmercialized monthly. The general adult urban population is exposed to low-level mercury concentration via fish consumption with an average daily intake of 0.2 mu g/kg (b.w.) and an estimated hazard quotient of 0.7. However, the fishermen families present an average daily intake of 2.2 mu g/kg (b.w.) and a hazard quotient of 8.6. The children of fi shermen families between 5 and 14 years old are the main risk group fo r Hg exposure via fish ingestion. Based on the uncertainty analysis, t he Hg fish concentrations and the fish ingestion rate were found to be the main parameters affecting the variability of the model outputs.