PHYTOREMEDIATION OF TRICHLOROETHYLENE WITH HYBRID POPLARS

Axenic tumor cultures of poplar cells, clone H11-11, were grown in the presence of [C-14]-trichloroethylene (TCE) (uniformly labeled). The c ells were capable of metabolizing TCE to produce trichloroethanol, di- and trichloroacetic acid. Some of the carbon from TCE was found in in soluble, nonextractable cell residue, and small amounts were mineraliz ed to [C-14]CO2. Poplar cuttings grown In soil and exposed to TCE prod uced the same metabolites, in field trials. trees were planted in soil in test cells and exposed to TCE via underground water injection duri ng the growing season. During the growing season, at least 95% of the TCE was removed from the influent water stream in cells containing tre es. Mass balance studies conducted in the laboratory indicated that 70 to 90% of the TCE was transpired; however, greenhouse and field study results showed that less than 5% of the total TCE taken up by the pla nts is transpired. These results show that significant TCE uptake and degradation occur in poplars. Poplars appear to be useful for in situ remediation of TCE-contaminated sites under proper conditions.