POTENCIAL EXPOSIÇÃO AO MERCÚRIO ATMOSFÉRICO NO AMBIENTE OCUPACIONAL DE COMÉRCIOS DE OURO DE PORTO VELHO, RONDÔNIA

The gold mining in the Madeira River basin is performed by dredges and ferries that extract from the bottom of the river alluvial gold which is amalgamated with mercury (Hg). Throughout the process of gold purification, the Hg can be recovered by retort or crucible distillation. Subsequently, the gold is taken to the city of Porto Velho for commercialization, once more being smelted with blowtorch for jewelry making. This study aims to evaluate the Hg concentration exposed in the atmosphere of gold shops via an atomic absorption spectrophotometer coupled to portable cold steam generation (LUMEX) and to determine the occupational exposure through the analysis of urine samples of gold shops workers. Eleven gold shops and twenty workers were investigated. Some risky situations which may accompany the health of employees, such as poor ventilation, lack of exhaust systems and unhealthy places, have been verified in loco. The results showed atmospheric concentrations of Hg above the limits established by WHO, which is at most 200 ng m-3 in four gold shops. All examined presented total Hg results in the urine below the occupational limit of (50.00 μg L-1)