Mercury speciation in surface freshwater systems in California and other areas

Mercury concentrations and speciation were determined in surface water samples from lakes and rivers in California and other areas. The freshwater systems studied ranged from a pristine alpine lake to a system with Hg-contaminated sediments. Dissolved organo-Hg compounds accounted for a majority (up to 89%) of the dissolved Hg in some lakes. Mercury concentration and speciation patterns in rivers were similar to that for lakes. The total Hg levels obtained in this present work, using clean sampling and analytical technologies, were considerably lower than most historical reports