Exposure to BPA in the womb is linked to behavioral and emotional difficulties in pre-school children, and girls in particular, concludes a new study published online in Pediatrics. The researchers suggest doctors may wish to advise patients concerned about this to reduce their exposure to consumer products likely to contain the chemical, although they point out that the “benefits of such reductions are unclear”.

The study is the work of researchers at the Harvard School of Public Health (HSPH), Cincinnati Children’s Hospital and Medical Center, and Simon Fraser University in Vancouver, British Columbia.

BPA stands for bisphenol A, a chemical used in the manufacture of plastic containers and other consumer products. It can be found in canned food linings, polycarbonate plastics, dental sealant, and some shopping receipts printed on thermal paper.

Exposure to BPA is a daily hazard for all people living in industrialized countries. Animal studies show it disrupts normal development and human studies have linked it to cardiovascular disease and diabetes.

Two years ago, researchers from HSPH conducted a study that found drinking from polycarbonate bottles increased the level of BPA in urine.

Now with this new study, lead author Dr Joe Braun, research fellow in environmental health at HSPH, and colleagues, suggest exposure to BPA in the womb is linked to behavioral and emotional problems just over three years later, especially in girls.

The study examined data from 244 mothers and their young children in the Cincinnati area who were taking part in the Health Outcomes and Measures of the Environment Study.

The data set included test results of urine samples taken from the mothers during pregnancy and at birth, and also from the children at age 1, 2 and 3. It also included survey responses from the mothers about their 3-year-old children’s behavior. The surveys were based on the Behavior Assessment System for Children 2 (BASC-2) and the Behavior Rating Inventory of Executive Function-Preschool (BRIEF-P).

Braun told the press:

“None of the children had clinically abnormal behavior, but some children had more behavior problems than others. Thus, we examined the relationship between the mom’s and children’s BPA concentrations and the different behaviors.”

They found that:

  • 85% of the mothers and 96% of the children had detectable levels of BPA in their urine.
  • There was little difference between the mothers’ in-pregnancy and at-birth levels of BPA.
  • The BPA levels in the children’s urine samples decreased from age 1 to age 3, but they were higher and varied more than their mothers’ levels.
  • After taking into account other possible influencers, BPA levels in pregnancy were linked to more hyperactive, aggressive, anxious, and depressed behavior and poorer emotional control and inhibition in the girls, but not the boys.

The researchers concluded that:

“… gestational BPA exposure affected behavioral and emotional regulation domains at 3 years of age, especially among girls. Clinicians may advise concerned patients to reduce their exposure to certain consumer products, but the benefits of such reductions are unclear.”

To reduce your exposure to BPA you would have to avoid canned and packaged foods, not touch sales receipts printed on thermal paper, and avoid polycarbonated bottles bearing the number 7 in the recycling symbol, say the researchers.

Braun said the findings confirm that of two previous studies that suggested pre-birth exposure to BPA affects child behavior, but it’s the first to show it’s more important than exposure after birth.

“Gestational, but not childhood BPA exposures, may impact neurobehavioral function, and girls appear to be more sensitive to BPA than boys,” said Braun.

Written by Catharine Paddock PhD