Chlordecone in the French Caribbean: there are effective ways to reduce dietary exposure

A risk of overexposure to chlordecone

In 2021, ANSES revised the external (dietary) health reference value for chlordecone in light of new toxicological and epidemiological studies, and established an internal (in blood) reference value. These values correspond to thresholds above which the risk of health effects cannot be ruled out.

In the expert appraisal published today, the experts compared these values with the data on dietary exposure and blood chlordecone levels from the Kannari study (2013-2014). They found that part of the French Caribbean population is at risk of being overexposed to chlordecone.

Limit the consumption of certain foods to reduce the risks associated with chlordecone

To avoid overexposure to chlordecone, the Agency issued three recommendations in its Opinion of 2007 aimed at limiting the consumption of certain foods acquired via informal channels:

• limit the consumption of fishery products acquired through short channels (leisure or subsistence fishing or bought from roadside vendors) to no more than four times a week;
• do not consume freshwater fishery products from areas where fishing is prohibited by prefectural order;
• limit the consumption of roots and tubers from family gardens in areas known to be contaminated to no more than twice a week. In the event of uncertainty, refer to the JAFA programme’s advisors.

In its new expert appraisal, ANSES concludes that complying with all three of these recommendations enables exposed populations to significantly reduce the risk of exceeding the external health value it established in 2021. It also shows that these recommendations are consistent with dietary practices in the French Caribbean, where the large majority of people already implement them. ANSES therefore confirms that these limitations on consumption are possible effective ways to reduce health risks for populations.

Controlling the contamination of home-produced food, especially eggs

The expert appraisal also revealed that the consumption of home-produced eggs in areas known to be contaminated contributes significantly to chlordecone exposure. Therefore, the Agency recommends stepping up membership and participation in the JAFA family garden programmes run by the Regional Health Agencies. These programmes monitor concentrations of chlordecone in soil and provide personalised advice on suitable farming practices for family gardens. Good practices include isolating animals from contaminated soil as much as possible and giving them non-contaminated feed.

New data are needed to identify other ways of reducing exposure to chlordecone

This expert appraisal was based on the data from the Kannari study carried out in 2013-2014. It also included more recent contamination data for food acquired through regulated channels. However, the Agency underlines the lack of new data on contamination and consumption habits for food acquired via informal channels.

New studies are under way that will provide more recent supplementary data. The ChlorExpo study, initiated by ANSES in early 2021, aims to obtain field data on food procurement, preparation and cooking practices. It will enable practical recommendations to be issued to continue reducing exposure to chlordecone in the French Caribbean. Moreover, the Kannari 2 biomonitoring study, which will soon be launched by Santé publique France, will enable the risk assessment to be updated based on human contamination data.

Lastly, ANSES recommends broadening the scope of investigation to include exposure to chemical contaminants other than chlordecone, with the aim of adapting and supplementing the measures taken to protect the French Caribbean population.

The results of the expert appraisal in figures

• Fourteen percent of the adult population in Guadeloupe and 25% in Martinique exceed the chronic internal toxicity reference value (TRV). The chronic internal TRV is based on chlordecone levels in blood. ANSES first set this value to 0.4 micrograms per litre of plasma in 2021. ANSES reiterates that this threshold is meant to be used to interpret blood chlordecone levels at the population level.
• Two to twelve percent of the French Caribbean population exceeds the chronic external TRV. The chronic external TRV concerns dietary exposure. It is set at 0.17 micrograms per kilogram of body weight per day.
• The rate at which the TRVs are exceeded is higher for individuals living in areas known to be contaminated than for those living in areas known to be free of contamination.