Éditeur(s) : HAL CCSD
Résumé : International audience
BACKGROUND: Several studies suggest that exposure to organophosphate insecticides (OP) during pregnancy impairs neurodevelopment in children. OBJECTIVES: We evaluated associations between biomarkers of prenatal and postnatal OP exposure and cognitive function of 6-year-olds in a French longitudinal birth cohort. METHODS: In 2002-2006, the PELAGIE mother-child cohort enrolled pregnant women from Brittany. For a random subcohort, we measured nonspecific dialkylphosphate metabolites (DAP) of OP in one maternal urine sample, collected before 19 weeks' gestation, and in one urine sample collected from their 6-year-old children. Six subtests of the Wechsler Intelligence Scale for Children-4th edition (WISC-IV) was administered at 6 years to evaluate cognitive function (n=231). Linear regression models controlling for factors including maternal intelligence and the Home Observation for Measurement of the Environment score were used. RESULTS: WISC-IV scores were not significantly associated with prenatal or childhood total DAP metabolites. WISC verbal comprehension score was significantly higher in association with the highest maternal urinary concentrations of diethylphosphate metabolites (DE) (5.5; 95% CI: 0.8, 10.3 for extgreater 13.2 nmol/L versus extlessLOQ), while WISC working memory score was significantly lower in association with the highest urinary concentrations of DE metabolites at age 6 years (-3.6; 95% CI: -7.8, -0.6 for extgreater 11.1 nmol/L versus extlessLOD). CONCLUSION: This study found no evidence that prenatal OP exposure adversely affected cognitive function in 6-year-olds, perhaps because of the higher population's socioeconomic status than in previous studies though other causal and non-causal explanations are also possible. The negative association between WISC score and concurrent DE urinary concentrations requires replication by longitudinal studies investigating childhood OP exposure
Environmental Health Perspectives

hal-01207282
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01207282
DOI : 10.1289/ehp.1409472
PUBMED : 26394442

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Due to their geographic location and traditional diet, rich in seafood and marine mammals, the Inuit living in Arctic Quebec are exposed to high amounts of pollutants, including organochlorine pesticides (OCPs). While the adverse developmental effects of these pesticides on child cognitive functions are well known, the effects of developmental exposure to OP on sensory processes have not been investigated. The aim of this longitudinal study was to assess the effects of prenatal and childhood exposure to 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p'-DDT) and its major metabolite 1,1,-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE), on visual processing in Inuit children in Nunavik (Arctic Québec). p,p'-DDT and p,p'-DDE concentrations were determined from umbilical cord and 5- and 11-year plasma samples. Visual evoked potentials (VEPs) were successfully recorded in 150 children at 4 contrast levels (95%, 30%, 12%, and 4%). Hierarchical multiple regressions were conducted to determine the association between p,p'-DDT, or p,p'-DDE, exposure and VEPs while controlling for the effects of various confounders, including fish nutrients and other contaminants. p,p'-DDE measured in umbilical cord plasma was significantly related to the amplitude of the N150 response at the lowest contrast (4%). In addition, 5-year p,p'-DDE plasma concentration was significantly associated with decreased N75 amplitude. These findings indicate that p,p'-DDE exposure, both pre- and postnatally, during early childhood is associated with visual processing impairment later in life.
ISSN: 0161-813X

hal-01061309
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01061309
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01061309/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01061309/file/Prenatal_and_5-year-NEUTOX-D-13-00192R2_v4.pdf
DOI : 10.1016/j.neuro.2014.04.009