A study published at the end of January in the peer-reviewed journal Environmental Health Perspectives says that women with higher exposure to phthalates during their pregnancy report more disruptive and problem behaviors in their children, using standardized measures. The study included 188 children whose mothers enrolled in Mount Sinai School of Medicine’s New York Children’s Environmental Health Study during their third trimester of pregnancy.

Phthalates are used in numerous consumer items, including cosmetics, fragrances, shampoos, lotions, and housing items like vinyl flooring. Research has indicated phthalates can interfere with reproductive and thyroid hormones. The researchers previously reported that prenatal phthalate exposure was associated with changes in newborn behavior, and their current objective was to assess their potential impact on neurobehavioral development in older children.

Ten phthalate metabolites were measured in the mothers’ urine collected during the third trimester of pregnancy. Mothers were interviewed one to three times while their children were 4 to 9 years old. Each time, the mothers completed standard questionnaires to assess their children’s behavior and cognitive functioning.

The researchers found that prenatal exposure to a group of phthalates commonly found in personal care products was significantly associated with poorer scores for problems with aggression, conduct, and emotional control. Associations did not appear to differ between boys and girls overall, and associations were stronger as levels of exposure increased. However, few children’s scores fell within the “at risk” or “clinically significant” range.

This study is the first to evaluate the neurobehavioral development of older children in relation to their phthalate exposure before birth. The data from this study are not sufficient to diagnose clinical conditions such as attention deficit/hyperactivity disorder. However, the results highlight an urgent need to further explore the relationship between phthalates and neurodevelopment.

The research was supported by NIEHS/EPA Children’s Center grants, the New York Community Trust, and the Agency for Toxic Substances and Disease Registry. Support was also provided by the National Institute of Child Health and Human Development.