Mercury distribution and speciation in waters of the coastal lagoons of Rio de Janeiro, SE Brazil

摘要: Abstract The distribution and speciation of Hg in surface waters from the coastal lagoons Rio de Janeiro State, Brazil, sampled 1997–1998, showed highest concentrations all species (reactive, total dissolved particulate) affected by metropolitan areas, where suspended solids (TSS) were, general, very high. Total varied 18.2 to 55.2 pM, one two orders magnitude higher than open ocean concentrations. Highest values were found located at area city, lowest hypersaline Araruama lagoon. Reactive (Hg 0 +HgII) 0.18 0.43 comprising less 2% Hg, a fraction much lower frequently reported for or plain estuaries. reactive was negatively correlated with Hg. Particulate (dissolved plus ranged 18 230 pM 37 285 respectively, TSS Mercury bottom sediments, on weight basis, 0.7 2.9 μg g −1 0.12 0.44 , respectively. However, water column did not correlate significantly sediments. results clearly show that most these is strongly bound forms. Also, high due resuspension sediments maintains large amounts both particulate column. Relatively low water–particle coefficients ( K D =0.6–5.5×10 5 ) suggest sorption/desorption processes as responsible this. These behavior similar described previously turbidity maximum zone Therefore, survey key biological components ecosystems recommended.