Mercury in the Moji-Guaçu River Basin, S.P—Brazil

Total mercury content was evaluated in water and suspended sediment samples of the Moji-Guaçu river and in water and bottom sediment of its 3 marginal lagoons (Catingueiro, Barrinha, and Rio das Pedras), located down-stream of the sampling point in the main channel. In all situations, low Hg concentrations were found in suspended and bottom sediments. Aluminum was used as a geo-chemical tracer to normalize the Hg concentrations in the sediment cores from the Rio das Pedras lagoon (r = 0.92). It was estimated that the Moji-Guaçu river transports up to 19 kg Hg yr−1, 65% in the dissolved form and 35% adsorbed onto particulate matter. Following an acute toxic stage observed in the years 1970–1980, the basin has been restored to its original conditions mainly by natural recovery and a general reduction in Hg input to the eco-system

Drainage basin · Geography · Geomorphology · Geotechnical engineering · Hydrology (agriculture · Mercury (programming language · Mineralogy · Particulates · Sediment · Structural basin · Tributary · Chemistry · Environmental Chemistry · Environmental Science · Geology · Heavy metals in environment · Mercury impact and mitigation studies · Water Quality and Pollution Assessment