Related Experiment Video
Updated: Dec 25, 2025
Visualizing Visual Adaptation
Published on: April 24, 2017
Visual contrast sensitivity in school-age Guadeloupean children exposed to chlordecone
Dave Saint-Amour1, Gina Muckle2, Avril Gagnon-Chauvin3
1Department of Psychology, Université duQuébec à Montréal, Montréal, Québec, Canada; Sainte-Justine University Hospital Research Center, Montréal, Québec, Canada; Department of Ophtalmology, Université de Montréal, Montréal, Québec, Canada.
Insights
Prenatal exposure to the pesticide chlordecone (a persistent organochlorine) is linked to reduced visual contrast sensitivity in children. This effect was particularly pronounced in boys, indicating potential neurodevelopmental impacts.
Area of Science:
- Environmental Health
- Neurotoxicology
- Pediatric Ophthalmology
Background:
- Chlordecone, a persistent organochlorine pesticide, was widely used in the French West Indies.
- Prenatal exposure to chlordecone has been previously linked to adverse infant neurodevelopmental outcomes.
- Visual contrast sensitivity is a critical aspect of visual function that may be affected by environmental toxins.
Purpose of the Study:
- To investigate the association between prenatal and postnatal chlordecone exposure and visual contrast sensitivity in school-aged children.
- To assess potential sex-specific differences in the impact of chlordecone on visual function.
- To evaluate the relationship between chlordecone levels and visual contrast sensitivity using a prospective birth cohort.
Main Methods:
- A prospective birth cohort study (TIMOUN) in Guadeloupe included 285 children aged 7.1–8 years.
- Visual contrast sensitivity was measured using the Freiburg Visual Acuity and Contrast Test (FrAcT).
- Chlordecone concentrations were measured in cord blood (prenatal) and child blood (postnatal); statistical analyses included multiple linear regression and sex-specific stratification.
Main Results:
- Higher prenatal chlordecone exposure (cord blood levels) was significantly associated with lower visual contrast sensitivity.
- No significant association was found between postnatal chlordecone levels and visual contrast sensitivity in the overall cohort.
- Sex-specific analyses revealed that prenatal chlordecone exposure was linked to reduced contrast sensitivity in boys, but not in girls.
Conclusions:
- Prenatal and childhood exposure to chlordecone may negatively impact visual contrast sensitivity in school-aged children.
- Boys appear to be more vulnerable to the visual effects of chlordecone exposure than girls.
- These findings highlight the potential long-term neurodevelopmental consequences of persistent pesticide exposure on visual system development.
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.
