MICROBIAL-DEGRADATION OF HYDROCHLOROFLUOROCARBONS (CHCL2F AND CHCL2CF3) IN SOILS AND SEDIMENTS

The ability of microorganisms to degrade trace levels of the hydrochlo rofluorocarbons HCFC-21 and HCFC-123 was investigated, Methanotroph-li nked oxidation of HCFC-21 was observed in aerobic soils, and anaerobic degradation of HCFC-21 occurred in freshwater and salt marsh sediment s, Microbial degradation of HCFC-123 was observed in anoxic fresh wate r and salt marsh sediments, and the recovery of 1,1,1-trifluoro-2-chlo roethane indicated the involvement of reductive dechlorination, No deg radation of HCFC-123 was observed in aerobic soils. In some experiment s, HCFCs were degraded at low (path per billion) concentrations, raisi ng the possibility that bacteria in nature remove HCFCs from the atmos phere.