Mercury contamination in hair of riverine populations of Apiacás reserve in the Brazilian Amazon

Abstract
Total and inorganic Hg in 55 samples of hair from riverines, mainly desoended from Mundunuku and Apiaká Indians, living along the rivers Teles Pires and Juruena have been determined. The sampled population represents 18% of the inhabitants of the region and they eat fish 6 or 7 days a week. Cold-vapor AAS and alkaline digestion with CdCl2/SnCl2 as reducing agent were employed to estimater total Hg in hair samples A LDC Analytical, A Mod. 1255, Mercury monitor was used for Hg determination. The mean value of total Hg was 34.2μg g−1, with an average of 87.2% of organic Hg Ninety-three per cent of the sampled population present levels of Hg above 10μg g−1 , and 180% over 50μg g−1. A relationship between the mean value of Hg and age ofthe sampled population is presented. All women at child-bearing age preset concentrations of Hg above 10μg g−1. Fifty-four per cent ofthem had levels ova 30μg g−1, with a mean of 41.2μg g−1. For the children under ten years of age, 14% show Hg concentration above 50μg g−1. Comparison of these results with those obtained in 10 other Amazon surveys (n=1672) is shown The results of the concentration of mercury in fish, mainly piscivorous (n=967) from Amazonian and Wetland (pantanal matogossense) are also presented, with a mean of 726 ng mg−1. These appears to be a relationship between level of Hg in human and their food ingestion habits.