HUMAN EXPOSURE TO MERCURY DUE TO GOLDMINING IN THE TAPAJOS RIVER BASIN, AMAZON, BRAZIL - SPECIATION OF MERCURY HUMAN HAIR, BLOOD AND URINE

To obtain the basic information on human exposure to mercury (Hg) due to gold mining activities in Amazon, total mercury (T-Hg) and methylme rcury (MeHg) were determined for human hair, blood and/or urine sample s collected from populations living in Bold mining area and fishing vi llages upstream of the Tapajos River basin. Abnormally high levels of T-Hg were observed in hair and blood from all fishing villages investi gated and more than 90% of T-Hg was in the form of MeHg. in both sampl es, whereas in goldmining area the value were much lower and the %MeHg values varied widely (20-100%) with individuals even in blood samples . Urine from gold shop workers contained Hg mostly in inorganic form a t 165 mu g/g creatinine on the average, with the range of 20 to 450 mu g/g creatinine. A good correlation between Hg in hair and blood was f ound in fishing villages end the ratios of hair Hg to blood Hand were very close to 250, generally established for MeHg. T-Hg, and inorganic Hg levels in urine from gold shop workers were also significantly cor related with inorganic Hg in blood.