Determination of carbon isotope enrichment factors of cis-dichloroethene after precursor amendment.

We found metabolite degradation and formation to be sequential but also stepwise during bacterial reductive dechlorination. The stepwise phases of the degradation of the intermediate eliminate the impact of instantaneous precursor degradation. These stepwise sections were used to determine εcis-DCE -values. Our results showed the validity of εcis-DCE -values over a wide range at initial precursor degradation (PCE). The presented evaluation method could substantially decrease lab costs for microcosm studies designed for εcis-DCE determinations. Moreover, the results indicated that the evaluation method can be applied to other PCE-metabolites.