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Chlordecone (Kepone or CLD) was formerly used in French West Indies as an insecticide. Despite its formal ban in 1993, high levels of this pesticide are still found in soils. Sequestering matrices like biochars or activated carbons (ACs) may decrease the bioavailability of halogenated compounds like CLD when added to contaminated soils. The present study intends (i) to produce contrasted sequestering matrices in order to (ii) assess their respective efficiency to reduce CLD environmental availability. This study involved two experimental steps. The first one consisted in the production of contrasted sequestering media (Biochars and ACs) using pyrolysis and distinct activation processes on two lignocellulosic precursors: oak wood (Quercus ilex) and coconut shell (Cocos nucifera). The chemical activation was made with phosphoric acid and physical activation with carbon dioxide and steam. Their physico-chemical properties were then characterized. In the second step, the CLD environmental availability was assessed either in an OECD artificial soil or in an Antillean contaminated nitisol (2.1 µg CLD per g of soil Dry Matter) amended with 5% of biochar or 5% of AC (mass basis). Main characteristics for coconut and oak biochars and ACs determined by nitrogen adsorption at 77K shows that mixed microporous and mesoporous structures (ranging from 30 % to 70%), high pore volume (ranging from 0.38 cm3.g-1 to 2.00 cm3.g-1) and a specific (BET) surface areas from 299.9 m2.g-1 to 1285.1 m2.g-1 resp. The amendment by lignocellulosic biochars did not limit CLD environmental availability in contrast to ACs which resulted in a significant reduction of the environmental availability in both artificial and natural soils. Thus, ACs amendment reduced CLD-transfer by at least 65% (P

Chlordecone (CLD) and γ-hexachlorocyclohexane (γ-HCH) are xenobiotics identified as persistent organic pollutants since 2009. Their presence in water and soils of banana and sugar crops production zones of the Caribbean islands, Guadeloupe and Martinica, led to a long term pollution of soils which is thought to last 5 to 7 centuries for the heaviest polluted andosoils. The National survey plans carried out since 2008 in Guadeloupe and Martinique revealed an unexpected contamination of animal products. This contamination is believed to result from concomitant soil ingestion by animals during pasture. The aim of this project is to formulate and test dietary non-absorbable substances with the aim to bind the compound in order to avoid its absorption or reabsorption. The use of activated carbons (ACs) prepared from biomass and exhibiting specific textural and physico-chemical properties to adsorb chlordecone and to avoid its absorption in the digestive tract, appear to be the most promising approach. Indeed, ACs are for example, widely used in the pharmaceutical industry as antidote in treatment of poisoning. Recent results demonstrated that the use of ACs has the potential to strongly reduce the bioavailability of CLD from soil for rearing animals (pigs and goats). ACs produced from locally available precursors, such as sugar cane bagasse, coconut shell with adequate textural and physico-chemical characteristics will be prepared to optimize these experiments. Two different strategies will be assessed: one performing an amendment of contaminated soil by AC, the other one bringing the AC via an additional feed.