Prenatal Methylmercury Exposure and child development at five years

Introduction: There is a worldwide concern about prenatal methylmercury (MeHg) exposure and its possible neurodevelopmental effects in susceptible children. We aimed to investigate whether the negative association found between prenatal MeHg exposure and communication skills seen at age three years in children in the Norwegian Mother and Child Cohort study (MoBa) remains at age five years. Methods: Maternal MeHg exposure was calculated from reported seafood intake in mid-pregnancy by a FFQ. Children’s communication development was measured using the Ages and Stages (ASQ) screening tool completed by the mother when the child was 3 and 5 years old. To identify children at risk, ASQ cut-offs were set at equivalent to 2 standard deviations below the mean indicating developmental delay. We examined associations between MeHg exposure and the measure of child communication delay with logistic regression, and further investigated the child’s receptive language and expressive language from the ASQ screening tool. ...