Plastics in common household items may cause fertility defects

The contaminant bisphenol-A (BPA)—widely used to make many plastics found in food storage containers and dental products—can have long-term effects in female development, according to a recent study by Yale School of Medicine researchers.

Lead investigator Hugh S. Taylor, M.D., associate professor in the Department of Obstetrics, Gynecology & Reproductive Sciences (Ob/Gyn) at Yale, said the study shows that BPA changes the expression of key developmental genes that form the uterus. Taylor explained that if pregnant women are exposed to the estrogen-like properties found in BPA, it may impact female reproductive tract development and the future fertility of female fetuses the mother is carrying.

The study was conducted on pregnant female mice by administering a range of doses of BPA on days 9-16 of their pregnancies. The aim was to see what interaction BPA would have with the HOXA10 gene, which is necessary for uterine development.

Taylor and co-author Caroline C. Smith of the Department of Epidemiology and Public Health at Yale School of Medicine, found that BPA does, in fact, alter the expression of the HOXA 10 gene, implying that exposure to the popular plastics component may lead to infertility in humans.

“The net effect is concerning,” said Taylor. “We are all exposed to multiple estrogen-like chemicals in industrial products, food and pollutants.”

BPA is found in plastics, including baby bottles, epoxy resins used in canned goods and dental sealants. In addition to this new link to fertility and reproductive health, previous findings by Csaba Leranth, M.D., also in Yale Ob/Gyn, found that low doses of BPA in female rats inhibited estrogen induction in the brain. This can lead to learning impairment and, in old age, the onset of neurodegenerative disorders such as Alzheimer’s disease.

Citation: The FASEB Journal (Journal of the Federation of American Societies for Experimental Biology) Vol. 21, 239-246 (January 2007)