With the purpose of checking the problem concerning mercury poisoning in prospectors, it was carried out a pilot study in two prospect areas in the State of Pará: Cachoeiro and Cumaru. We collected 35 samples of hair following the recommendations of the International Atomic Energy Agency. For dosing mercury contents in these samples we used the method of atomic absorption through the technique of cold steam. The overall mercury was detected in 100% of the samples which have been analysed. In the group of prospectors of Cachoeiro the mercury contents found varied with an amplitude of 1.97 - 68.98 ppm, X = 11.49 ppm, while in the group of prospectors of Cumaru the amplitude was of 1.50 - 13.68 ppm, X = 5.18 ppm. These results show the high risk of exposition to which the population of prospectors in subjected. We hipothezed that other social groups in this area, e.g., caiapó natives of the Gorotire Reserve, are being indirectly affected.
