Geochemical mapping and background concentrations of iron and potentially toxic elements in active stream sediments from Carajás, Brazil – implication for risk assessment

Abstract The Companhia de Pesquisa de Recursos Minerais (CPRM - Geological Survey of Brazil) has conducted geochemical surveys in the south-central region of the Itacaiunas River watershed (IRW) in the Carajas region. The surveyed area covers 9,650 km 2 and the data obtained by CPRM is the basis for the present study. A total of 833 active stream sediment samples, including 144 duplicates were collected. The