Chlordecone in the French West Indies (Martinique and Guadeloupe)

Chlordecone (trade names Kepone, later Curlone) is an organochlorine insecticide. The United States banned it after workers at the Hopewell plant in Virginia were poisoned in the mid-1970s. France gave it a provisional authorisation in 1972 and it was used on the banana plantations of Martinique and Guadeloupe against the banana weevil. The authorisation was withdrawn in February 1990, but successive derogations allowed its use in the islands until 30 September 1993. According to French Wikipedia, about 300 tonnes were spread over those twenty-one years, at 3 kg per hectare per year.

The molecule binds strongly to the volcanic soils (andosols and nitisols) and hardly degrades. From the fields it reaches rivers, groundwater and the coast, and from there root and tuber crops, eggs, livestock, freshwater crustaceans and fish. Contamination of water and food came to light in the late 1990s and early 2000s; since 2008 the State has launched four successive plans.

In January 2023 the investigating judges in Paris closed the criminal inquiry opened by complaints from Antillean associations with a dismissal, finding the facts time-barred while speaking of a "health scandal". On 11 March 2025 the Paris administrative court of appeal found the State at fault for authorising and prolonging the use of the product and ordered it to compensate 11 of about 1,300 claimants for anxiety damage (Reporterre).

Remediation research follows three lines: in situ chemical reduction with zero-valent iron, tested at plot scale in a Martinique banana plantation; sequestration with biochar and activated carbon, to reduce transfer to plants and animals; and anaerobic microbial degradation, shown in the laboratory.