HIGH-CONCENTRATIONS OF TOXAPHENE IN FISHES FROM A SUB-ARCTIC LAKE

Concentrations of toxaphene and other organochlorine compounds are hig h in fishes from subarctic Lake Laberge, Yukon Territory, Canada. Nitr ogen isotope analyses of food chains and contaminant analyses of biota , water, and dated lake sediments show that the high concentrations of toxaphene in fishes from Laberge resulted entirely from the biomagnif ication of atmospheric inputs. A combination of low inputs of toxaphen e from the atmosphere and transfer through an exceptionally long food chain has resulted in concentrations of toxaphene in fishes that are c onsidered hazardous to human health.