TOTAL CONCENTRATIONS OF MERCURY IN WISCONSIN (USA) LAKES AND RIVERS

We analyzed surface waters from 30 Wisconsin lakes and rivers for tota l mercury ([Hg](T)) and total suspended particulates (TSP) on a state- wide basis with trace-metal 'ultraclean' techniques. Mercury concentra tions ranged from 0.3 to 2.9 ng L(-1) in lakes and from 0.7 to 8.9 ng L(-1) in rivers. TSP concentrations ranged from 0.9 to 6.6 mg L(-1) in lakes and from 3.1 to 31.4 mg L(-1) in rivers. Spatial trends were we ak; however, [Hg](T) was generally higher in the spring than in the au tumn of 1991. Total mercury concentration was weakly dependent on TSP with the coefficient of determination (r(2)) ranging 0.06 to 0.49 acro ss seasonal and geophysical differences.