Mercury lakes

Lake alkalinity values were significantly lower relative to stream samples collected during the same period. Stream alkalinities averaged about 5.1 whereas lake alkalinities had a mean value of 2.1 mg/1. Calcium lake concentrations were similar to stream values little to no depth variation in calcium concentrations was observed during the approximate seven and one-half week period. Lfegnesium lake concentrations also closely paralleled stream water concentrations stream concentrations averaged about 0.6 mg/1 the lake mean value for all depths was 0.5 mg/1. The mean mercury lake concentration was 29.1 mg/1 which compared with the 33 mg/1 mean value observed for all str m samples. Lake nitrates were similar to stream concentrations whereas lake pH values ware... 

Sodium selenite has also been incorporated into styrene—butadiene mbber and used in a pellet form which results in the slow release of selenium into water. These pellets have been placed in lakes in Sweden which have fish contaminated with mercury owing to high levels of that element in the water. The selenium released by the pellets reacts with mercury to form insoluble, heavy mercury selenide which setties to the lake bottom and removes mercury from the ecosystem (126). 

In many ways, both Canada and the United States continue to be involved in a unique experiment of co-operative management of serious environmental issues which plague a shared international resource. Despite the institutional complexity and the history of abuse that man s activities have wrought on the Great Lakes, the experiment to restore and protect them has had several successes typhoid and cholera were eradicated eutrophication problems are now largely under control and where adequate control programs for toxic chemicals have been implemented and enforced (e.g., mercury, DDT, PCBs), there have been associated declines in concentrations in the lakes. These successes have been due in no small way to the spirit of co-operation that has continued to exist between Canada and the United States and the unique institutional arrangements entered into by the two countries. 

The Decline in Mercury Conceruration in Fish from Lake St. Clair, 1970-1976, Report No. AQS77-3, Ontario Ministry of the Environment, Toronto, Ontario, 1977, 85p. 

Kennedy, E.J. Ruch, R.R. Shimp, N.F. Distribution of Mercury in Unconsolidated Sediments From Southern Lake Michigan. Environ. Geo. 1971 Notes 44. 

Syers, J.K. Iskandar, I.K. Keeney, D.R. Distribution and Background Levels of Mercury in Sediment Cores from Selected Wisconsin Lakes. Water Air Soil Pollut. 1973 2, 105-118. 

Pak K-R, R Bartha (1998) Mercury methylation and demethylation in anoxic lake sediments by strictly anaerobic bacteria. Appl Environ Microbiol 64 1013-1017. 

While methylmercury occurs naturally in tlie environment, it is reasonable to expect that methylmercury levels have increased in modem times as a result of increased inorganic mercury concentrations. Whether methylmercmy concentrations have increased to a similar extent as inoiganic mercuiy is not known. It is clear, however, that elevated fish mercuiy concentrations can currently be found in remote lakes, rivers, reservoirs, estuaries, and marine conditions, typically in predators such as sportfish at the top of food webs. As of 2003, 45 states had fish consumption advisories related to mercuiy, and 76% of all fish consumption advisories in the United States were at least partly related to mercury (USEPA 2004a). The number of advisories is increasing with time, although this is due at least partly to more sites being sampled (Wiener et al. 2003). 

Hrabik TR, Watras CJ. 2002. Recent declines in mercury concentration in a freshwater fishery isolating the effects of de-acidification and decreased atmospheric mercury deposition in Little Rock Lake. Sci Total Environ 297 229-237. 

Lockhart WL, Wilkinson P, BiUeck BN, Hunt RV, Wagemann R, Brunskill GJ. 1995. Current and historical inputs of mercury to high-latitude lakes in Canada and to Hudson Bay. Water, Air Soil Pollut 80(1 ) 603-610. 

Lorey P, Driscoll CT. 1999. Historical trends of mercury deposition in Adirondack lakes. Environ Sci Technol 33 718-722. 

Lucotte M, Mucci A, Hillaire-Marcel C, Pichet P, Grondin A. 1995. Anthropogenic mercury enrichment in remote lakes of northern Quebec (Canada). Water Air Soil Pollut 80 467-476. 

Watras C J, Bloom NS, Hudson RIM, Gherini SA, Munson R, Klaas SA, Morrison KA, Hurley J, Wiener JG, Fitzgerald WF, Mason R, Vandal G, Powell D, Rada R, Rislove L, Winfrey M, Elder J, Krabbenhoft D, Andren AW, Babiarz C, Porcella DB, Huckabee HW. 1994. Sources and fates of mercury and methylmercury in remote temperate lakes. In Watras CJ, Huckabee JW, editors. Mercury pollution — integration and synthesis. Boca Raton (FL) Lewis Publishers, p. 153-177. 

Kamman NC, Lorey PM, Driscoll CT, Estabrook R, Major A, Pientka B, Glassford E. 2003. Assessment of mercury in waters, sediments, and biota of New Hampshire and Vermont lakes, USA, sampled using a geographically randomized design. Environ Toxicol Chem 23 1172-1186. 

Landis MS, Vette AF, Keeler GJ. 2002. Atmospheric mercury in the Lake Michigan Basin influence of the Chicago/Gary urban area. Environ Sci Technol 36(13) 3000-3009. 

FIGURE 3.1 Observed mercury concentrations in standardized 50-cm walleye from Clay Lake, Ontario (1970-1983) following reductions in mercury releases from an upstream chlor-aUcali facility. (Source Data from Parks and Hamilton 1987.)... 

Babiarz CL, Andren AW. 1995. Total concentrations of mercury in Wisconsin (USA) lakes and rivers. Water Air Soil Pollut 83 173-183. 

Balogh SJ, Engstrom DR, Ahnendinger JE, Meyer ML, Johnson DK. 1999. A history of mercury loading in the upper Mississippi River reconstructed from the sediments of Lake Pepin. Environ Sci Technol 33 3297-3302. 

Brndler R, Renberg I, Appleby PG, Anderson NJ, Rose NL. 2001. Mercury accumulation rates and spatial patterns in lake sediments from west Greenland a coast to ice margin transect. Environ Sci Technol 35 1736-1741. 

Engstrom DR, Polhnan CD, Fitzgerald WF, Balcom PH. 2003. Evaluation of recent trends in atmospheric mercury deposition in south florida from lake-sediment records. Tallahassee (FL) Florida Department of Environmental Protection, 27 pp. 

Henry EA, Dodge-Murphy LJ, Bigham GN, Klein SM, Gilmour CC. 1995. Total mercury and methylmercury mass balance in an alkaline, hypereutrophic urban lake (Onondaga Lake, N.Y.). Water Air Soil Pollut 80 489 98. 

Hurley JP, Watras CJ, Bloom NS. 1994. Distribution and flux of particulate mercury in four stratified seepage lakes. In Watras CJ, and Huckabee J, editors. Mercury as a global pollutant integration and synthesis. Chelsea (MI) Lewis, p. 69-82. 

Hurley JP, Cowell SE, Shafer MM, Hughes PE. 1998. Tributary loading of mercury to Lake Michigan importance of seasonal events and phase partitioning. Sci Total Environ 213 129-137. 

Kanunan NC, Engstrom DR. 2002. Historical and present fluxes of mercury to Vermont and New Hampshire lakes inferred from Pb dated sediment cores. Atmos Environ 36 1599-1609. 

Rolfhus KR, Sakamoto HE, Cleckner LB, Stoor RW, Babiarz CL, Back RC, Manolopoulos H, Hurley JP. 2003. The distribution of mercury in Lake Superior. Environ Sci Technol 37 865-872. 

Wang W, Driscoll CT. 1995. Patterns of total mercury concentrations in Onondaga Lake, New York. Environ Sci Technol 29 2261-2266. 

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