Organochlorines in the water and biota of Lake Baikal, Siberia

Organochlorine contaminants were measured in water, fish, and Baikal seal from Lake Baikal, Siberia. Organochlorine levels in water were comparable to those reported from the upper Great Lakes, with the exception of chlordanes, which were a factor of 2 lower. Dissolved toxaphene and ΣDDT (sum of 4,4'-DDE, 4,4'-DDD, 2,4'-DDT, and 4,4'-DDT) averaged 64±37 pg/L and 87±37 pg/L, respectively. Total polychlorinated biphenyl (ΣPCB) concentrations in biota ranged from 1.2 to 26 mg/kg of lipid in the omul (an endemic salmonid) and the Baikal seal, respectively. Tetra- and pentachlorobiphenyl congeners accounted for a greater proportion of ΣPCB in omul and hexa-, hepta-, and octachlorobiphenyl congeners in pelagic sculpins and seal