抄録
Biotransformation of trichloroethylene (TCE) in a soil sample was examined in sealed vials. A soil sample was collected from the ground inside the metal welfare factory ; it was located in the area where groundwater was contaminated by a degreaser, TCE, and cis-1, 2-dichloroethylene (cis-DCE), which had not been used in the vicinity. TCE was transformed into cis-DCE in 1 week in the collected unsterilized soil suspension. On the other hand, TCE did not degrade in the sterilized soil suspension. When 0.05 ml soil suspension was transferred to another sterilized soil suspension, this transformation was observed. This reaction was stopped by heating in boiling water for 10 min. Therefore, this transformation was considered to be due to a microbial dechlorination. The trans-1, 2-dichloroethylene, 1, 1-dichloroethylene and vinyl chloride were not detected by this TCE biotransformation. The cis-DCE did not further degrade at least in 3 weeks. It can therefore be presumed that cis-DCE contained in groundwater near the factory is a biotransformation product of TCE.
