학술논문

Distinct Carbon Isotope Fractionation Signatures during Biotic and Abiotic Reductive Transformation of Chlordecone
Document Type
Article
Source
Environmental Science & Technology; 20240101, Issue: Preprints
Subject
Language
ISSN
0013936X; 15205851
Abstract
Chlordecone is a synthetic organochlorine pesticide, extensively used in banana plantations of the French West Indies from 1972 to 1993. Due to its environmental persistence and bioaccumulation, it has dramatic public health and socio-economic impact. Here we describe a method for carbon-directed compound specific isotope analysis (CSIA) for chlordecone and apply it to monitor biotic and abiotic reductive transformation reactions, selected on the basis of their distinct product profiles (polychloroindenes versus lower chlorinated hydrochlordecones). Significant carbon isotopic enrichments were observed for all microbially mediated transformations (ebulk= -6.8‰ with a Citrobacterstrain and ebulk= -4.6‰ with a bacterial consortium) and for two abiotic transformations (ebulk= -4.1‰ with zerovalent iron and ebulk= -2.6‰ with sodium sulfide and vitamin B12). The reaction with titanium(III) citrate and vitamin B12, which shows the product profile most similar to that observed in biotic transformation, led to low carbon isotope enrichment (ebulk=-0.8‰). The CSIA protocol was also applied on representative chlordecone formulations previously used in the French West Indies, giving similar chlordecone d13C values from -31.1 ± 0.2‰ to -34.2 ± 0.2‰ for all studied samples. This allows the in situ application of CSIA for the assessment of chlordecone persistence.