From 2015 to 2018, 18,285 initial lead screening tests were recorded in France, including the overseas departments and regions (DROM). During the same period, French Guiana accounted for 2,183 of these tests—12% of the total—even though the population of French Guiana represented only 0.42% of the French population (including DROMs) in 2019.

Children aged 1 to 6, boys, and minors living along the river rather than the coast are the most affected. Nevertheless, these results must be interpreted with caution, as girls are screened more frequently than boys in the 7–18 age group. The boys identified may represent only severe cases of poisoning, which would therefore increase their average blood lead level. This difference in numbers (twice as many girls as boys, particularly in the 7–18 age group) suggests that it is primarily pregnant minors who are screened during their pregnancy.

The targets for reducing blood lead levels in the general population set by the HCSP are an average blood lead level of 12 µg/L and 98% of the population with a blood lead level below 40 µg/L. Among minors screened for the first time between 2011 and 2018, we observe an average (geometric) blood lead level of 37.4 µg/L, and only 52% of children have blood lead levels below 40 µg/L. In addition, nearly 40% of children in French Guiana have blood lead levels above 50 µg/L, and 68% of the French Guianese population screened for the first time have blood lead levels above 25 µg/L, which corresponds to the vigilance threshold. The situation in French Guiana is therefore very concerning.

An increase in the incidence rate was observed between 2011–2015 and 2015–2018, which can be explained by the change in the threshold value defining lead poisoning. However, in approximately 43% of cases, no notification form was submitted to the ARS. This underreporting is due to several factors, including prescribers’ failure to report blood lead levels and a lack of awareness regarding lead poisoning. However, the failure to report a case or delays in reporting have consequences for the child, as exposure persists.

Lead exposure levels in French Guiana are very high compared to those measured in mainland France. The causes remain poorly defined, but sources of poisoning differ from those in mainland France; indeed, lead-based paints and lead pipes are rarely found in French Guiana. The sources identified in the region rarely suffice on their own to explain the level of lead found in children. Unlike the risk factors identified by the SNSPE analysis, the literature and environmental surveys suggest multifactorial exposure, with a predominantly dietary component, as the primary source of lead poisoning in French Guiana.

Lead is naturally present in certain types of cassava and therefore in some of their derivatives. To date, we have not detected the presence of lead in fish or game prior to human intervention in French Guiana. Nevertheless, lead can be found in these foods when they are caught, hunted, and prepared. Lead passes from fishing weights to fish, from lead shot to game meat, and accumulates on the knife used to cut the weights and subsequently to cut the food.

The situation requires further in-depth investigation, including an analysis of the different types of cassava and the soil. Only through cooperation with and listening to the various affected communities in French Guiana, as well as raising awareness among healthcare professionals, will it be possible to develop effective and appropriate solutions.