A new case study examining an infant's neurobehavioral abnormalities and extremely high bisphenol A (BPA) concentration of the baby's mother suggests a link between the two. The study, Environmental Health Perspectives: A Case Study of High Prenatal Bisphenol A Exposure and Infant Neonatal Neurobehavior, was led by researcher Sheela Sathyanarayana, MD of Seattle Children's Research Institute, and recently published online in Environmental Health Perspectives.
BPA, a synthetic, man-made chemical, is used in a wide variety of products including: can linings; hard polycarbonate plastics such as baby bottles and reusable cups; and dental sealants. Food may be the single largest source of BPA exposure due to contamination of foods during preparation and processing. BPA has estrogenic (hormone-like) properties. In animal studies, exposure to BPA early in life can lead to a variety of abnormalities in early development of the brain, behavior, prostate gland and breast tissues.
In human studies, exposure to BPA early in life has not been studied extensively. However, one study found an association between BPA exposure in pregnancy and abnormal acting out behaviors in female children. In adults, increased BPA exposure has been associated with changes in hormone concentrations, sperm quality, and endometriosis.
"Pregnant women are often exposed to BPA in their daily lives," said Sathyanarayana, pediatrician and environmental health specialist at Seattle Children's and assistant professor of pediatrics at the University of Washington School of Medicine. "It's important that they are aware of the potential sources of BPA, so they can take steps to avoid unnecessary exposures."
In this case study, Sathyanarayana and co-investigators reported on a specific mother/infant pair from a larger study (Health Outcomes and Measures of the Environment - HOME study) that examined BPA exposures in pregnant women and then examined their infants for neurodevelopmental outcomes. At 27 weeks of pregnancy, the mother had the highest reported urinary BPA concentration of anyone in the general population. She reported consuming canned foods and beverages, and using and microwaving plastic food storage containers consistently during this pregnancy time period. All of these exposures could have led to her extremely high BPA concentration. Her infant had a normal newborn neurobehavioral exam but had many neurobehavioral abnormalities at the one-month study visit including: increased muscle tone, tremors, and abnormal movements. The child went on to have normal neurobehavioral assessments yearly from one to five years of age.
This case study confirms previous studies documenting multiple sources of BPA exposure in humans. Additionally, it highlights the need for medical providers to be aware of the harmful effects of BPA exposures so they may counsel families appropriately about prevention. The study also identifies potential sources of BPA exposure that can be targeted to reduce exposures in the future. "Families can decrease their exposure to BPA by eating fresh fruit and vegetables (as opposed to processed and canned foods) and by decreasing use of plastic food storage containers," said Sathyanarayana. "Check the recycling code of your plastics on the bottom. If it shows #7, then the plastic may contain BPA."
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