BPA is the commonly used designation for bisphenol A, a chemical found in many rigid plastic products, food and formula can linings, dental sealants, and on the shiny side of paper cashier receipts (to stabilize the ink). The structure of BPA resembles estrogen, and as a result, exposure to it can affect how estrogen and other hormones act in the body, by mimicking or blocking them. This can disrupt the body's hormonal balance.
Many women choose to limit their exposure to BPA and other estrogen-like chemicals because it is known that estrogen can make hormone-receptor-positive breast cancer develop and grow. Some experts have expressed concern that BPA exposure in early life may lead to an increased breast cancer risk later in life.
A recent study found that breast tissue development in primates exposed prenatally to BPA was more advanced compared to breast tissue development in those not exposed to BPA, a finding that could be linked to increased breast cancer risk later in life. The study was published online May 7, 2012, in the journal Proceedings of the National Academy of Sciences of the United States of America (PNAS). Read the abstract of Bisphenol A alters the development of the rhesus monkey mammary gland.
The researchers gave some pregnant monkeys BPA in their diet, resulting in their blood levels of BPA being comparable to those typically found in U.S. women. Other pregnant monkeys were not given BPA. After the baby monkeys were born, the researchers biopsied the breast tissue of baby monkeys, and then they compared the biopsy findings for the baby monkeys exposed to BPA to the findings for those not exposed to BPA.
They found that the babies who had been exposed to BPA while in their mother’s uterus showed signs of more advanced breast tissue development. This advanced development of breast tissue during fetal and early life could set the stage for an increased risk of being diagnosed with breast cancer later in life.
In the Breastcancer.org Lower Your Risk section you can learn much more about what we know about breast cancer risk factors and what you can do to minimize your personal risk. For more specific information on risks from plastics and what you can do about those risks, visit the Breastcancer.org Exposure to Chemicals in Plastic pages.