LONG-RANGE ATMOSPHERIC TRANSPORT OF TOXAPHENE TO LAKE BAIKAL

Complex mixtures of chlorinated bornanes and bornenes (CHBs), typically referred to as toxaphene or polychlorinated camphenes, were measured in the air and surface water of Lake Baikal, Russia during June, 1991. The mean CHB concentration was 16 +/- 4 pg m-3 in air and 64 +/- 37 pg/L in water. Levels in air were similar to previous measurements in Arctic regions, and the chromatographic pattern of CHB congeners was extremely ''weathered'' compared to a toxaphene standard suggesting long-range atmospheric transport rather that a nearby source. The congener pattern in the water samples was similar to that in the air indicating the importance of atmospheric deposition processes to Lake Baikal. Estimates of gas flux of CHBs across the air-water interface predict that this process could cause a substantial contribution to the lakes' overall pollutant budget.