Assessment of hexachlorcyclohexane biodegradation in contaminated soil by compound-specific stable isotope analysis.

Assessment of hexachlorcyclohexane biodegradation in contaminated soil by compound-specific stable isotope analysis. Environ Pollut. 2019 Aug 02;254(Pt A):113008 Authors: Qian Y, Chen K, Liu Y, Li J Abstract Compound-specific isotope analysis (CSIA) was firstly applied to explore the biodegradation of hexachlorcyclohexane (HCH) isomers in contaminated soil. Concentrations and compound-specific carbon isotope ratio profiles of HCH in different specific ex-situ pilot-scale contaminated soil mesocosms were determined. The addition of nutrients and Sphingobium spp. significantly enhanced the degradation of HCH in contaminated soils within 90 days. Isomer specific biodegradation of HCHs was observed with α- and γ-HCH being more degradable than β and δ-HCH. Stable carbon isotope fractionation of HCH was observed and the δ13C values shifted from -28.8 ± 0.3‰ to -24.8 ± 0.7‰ upon 87.3% removal, -27.9 ± 0.2‰ to -25.9 ± 0.5‰ upon 72.8% removal, -29.4 ± 0.3‰ to -19.9 ± 0.6‰ upon 95.8% removal, and -27.8 ± 0.5‰ to -23.6 ± 0.7‰ after 96.9% removal for α, β, γ, and δ-HCH, respectively. Furthermore, the enrichment factor ε for α, β, γ, and δ-HCH biodegradation in soil was obtained for the first time as -2.0‰, -1.5‰, -3.2‰, and -1.4‰, which could play a critical role in assessing in situ biodegradation of HCH isomers in field site soil. Results from ex-situ pil...
Source: Environmental Pollution - Category: Environmental Health Authors: Tags: Environ Pollut Source Type: research