Visual contrast sensitivity in school-age Guadeloupean children exposed to chlordecone.

Abstract Recent evidence suggests that prenatal exposure to chlordecone, a persistent organochlorine pesticide that was used intensively in the French West Indies, affects infant neurodevelopment. The aim of the present study was to evaluate the association between prenatal and postnatal chlordecone exposures on visual contrast sensitivity in 285 children aged from 7.1 to 8 years old (mean age = 7.68 ± 0.21 years; sex ratio = 54 % girls) in a Guadeloupean prospective birth cohort (TIMOUN). The Freiburg Visual Acuity and Contrast Test (FrAcT) was used to assess visual contrast sensitivity. Chlordecone concentrations were measured in blood samples at birth (cord blood) and in children at testing time to estimate pre- and postnatal exposure, respectively. Exposures were categorized into three groups and were also log-transformed and considered as continuous variables. Multiple linear regression models were performed on all children taking into account various potential confounders, including maternal characteristics (age, education, intellectual functioning, alcohol and tobacco use during pregnancy). Potential moderation effect of sex was also examined. Results showed that higher cord plasma chlordecone levels were associated with lower contrast sensitivity. Although child chlordecone levels was not associated with the FrAcT, sex-specific stratified analyses revealed significant associations in boys. Associations between postnatal exposure and FrACT scores in girls were null. This study indicates that exposure to chlordecone in utero and during childhood may impair visual contrast sensitivity at school age, particularly in boys.