Kinetic study of chlordecone orally given to laying hens (Gallus domesticus)

•A kinetic study of chlordecone ingested in laying hens was conducted.•Chlordecone preferentially accumulated in liver.•The steady state carry over rate of chlordecone to egg reached 43%.•The depuration half-life ranged between 5.0 and 5.5d, depending on the tissue.•The risk of contamination of products from laying hens reared outdoor is high. The former use of chlordecone (CLD) in the French West Indies has resulted in long-term pollution of soils. In this area, CLD may be transferred into eggs of hens reared outdoors, through soil ingestion. In order to assess this risk, a kinetic study involving the contamination of laying hens (22weeks of age) with a diet containing 500μgCLDkg−1 during 42d, followed by a depuration period of 35d was carried out. Forty-four hens were sequentially slaughtered all over the experimental period and their liver, egg, abdominal fat and serum were collected. Two additional edible tissues, pectoral and leg muscles, were collected in hens slaughtered at the end of the contamination period. The depuration half-life of CLD in liver, egg, abdominal fat and serum was estimated at 5.0±0.38 (mean±SE), 5.5±0.29, 5.3±0.37 and 5.1±0.66d, respectively. CLD concentration at the end of the contamination period reached 1640±274, 460±41, 331±23, and 213±8.5μgkg−1 fresh matter (FM), respectively. The corresponding concentrations in pectoral and leg muscles were 119±8.4, 127±11μgkg−1 FM, respectively. The steady state carry over rate of CLD in eggs reached 43±7.6%. This experiment demonstrates the preferential accumulation of CLD in liver, its significant transfer to eggs and its quite short half-life. It is concluded that raising hens on even mildly contaminated areas would lead to products exceeding the regulatory maximum residue limit of 20μgCLDkg−1.