Posted on Jun 20, 2012, 6 a.m.
Fetal exposure to the plastic additive BPA has been shown to alter mammary gland development in primates, thus providing further evidence to suggest that it plays a role in the development of breast cancer in humans.
Results of a new study, this time in primates, have provided yet more evidence to suggest that the plastic additive bisphenol A (BPA) may play a role in the development of breast cancer in humans. The study was designed by Hunt and Tufts University School of Medicine researchers Ana Soto and Carlos Sonnenschein, and Catherine VandeVoort from the University of California at Davis. The researchers compared the structure of the mammary gland in newborn rhesus macaques exposed to BPA to the mammary glands of macaques that had not been exposed to the chemical. In order to expose the baby macaques to BPA, their mothers were fed a fed a piece of fruit containing a small amount of BPA each day during the gestational period corresponding to the human third trimester of pregnancy. This resulted in blood levels of BPA comparable to the average US citizen. Results showed that the density of the mammary buds at birth was significantly increased in the BPA-exposed macaques. Furthermore, the overall development of the mammary gland was more advanced in the BPA-exposed macaques than it was in the unexposed animals. "This study buttresses previous findings showing that fetal exposure to low xenoestrogen levels causes developmental alterations that in turn increase the risk of mammary cancer later in life," concluded Soto. "Because BPA is chemically related to diethylstilbestrol, an estrogen that increased the risk of breast cancer in both rodents and women exposed in the womb, the sum of all these findings strongly suggests that BPA is a breast carcinogen in humans and human exposure to BPA should be curtailed." In March, the Food and Drug Administration refused to ban BPA, but said that it would continue to carry out research on its effects on health.
Andrew P Tharp, Maricel V Maffini, Patricia A Hunt, Catherine A VandeVoort, Carlos Sonnenschein, Ana M Soto. "Bisphenol A alters the development of the rhesus monkey mammary gland." Proc Natl Acad Sci U S A. Published ahead of print May 7, 2012.