Alpha-, Beta-, Delta-, and Gamma- hexachlorocyclohexane dechlorinating enrichment cultures. Enriched hexachlorocyclohexane isomers-dechlorinating cultures

Intensive historical and worldwide use of the persistent pesticide technical-grade hexachlorocyclohexane (HCH), composed of the active ingredient γ-HCH (called lindane) along with several other HCH isomers, has led to widespread contamination. We derived four anaerobic enrichment cultures from HCH-contaminated soil capable of sustainably dechlorinating each of α-, β-, γ-, and δ-HCH isomers stoichiometrically and completely to benzene and monochlorobenzene (MCB) over two years. Cultivation with a different HCH isomer resulted in distinct bacterial communities. This study provides the first direct comparison of shifts in anaerobic microbial communities induced by the dechlorination of distinct HCH isomers.