In order to investigate the major sources and cycling of mercury in the Neg
ro River Basin (Amazon), total metal measurements were carried out in soils
, in river and lake waters, in the atmosphere, and in bulk precipitation du
ring the period 1995 throughout 1998. Median values of 1.3 ng m(-3) in the
atmosphere, 172 mug kg(-1) in soils, 4.6-7.5 ng l(-1) in three different la
kes, 4.5 ng l(-1) in 17 different Negro River tributaries and 20.3 mug m(-2
) year(-1) in bulk precipitation were found. Mercury concentrations in rive
rs and lakes waters, as well as in soils and bulk precipitation were high,
considering the scarcity of anthropogenic point sources in the region. Merc
ury leaching from soil, the largest regional reservoir of this metal, was c
onsidered to be the major pathway to mercury enrichment in the region. (C)
2001 Elsevier Science B.V. All rights reserved.