Photo credit: Wouter Vandenneucker

A recent study published in the Journal PLOS ONE has found an association between maternal exposure to phthalates—chemicals commonly found in plastics and personal care products—and lowered IQ in their seven-year-old children. Previous studies had found that phthalate exposure in pregnant women has negative effects on their children. For instance, prenatal phthalate exposure was associated with delayed motor development in three-year-olds. However, no previous studies had investigated the effect of prenatal exposure on IQ in school-age children. Researchers studied 328 inner-city women and their seven-year-old children from the Columbia Center for Children’s Environmental Health longitudinal birth cohort. Subjects were excluded if they were smokers, had a history of drug abuse, or had other medical problems. Urine samples previously taken from the mothers when they were pregnant were analyzed for chemicals created when the body breaks down phthalates, and their children were given an IQ test. Researchers found significant associations between the level of phthalate exposure in the women when they were pregnant and the IQ of their children. Higher phthalate exposure was linked to lower IQ. This association was stronger in girls than in boys. “These findings are important to inform policy makers of the potentially harmful effects of this class of chemical,” the authors concluded.