Exposure to BPA during pregnancy increases the risk of prostate cancer in male offspring, according to a new study.

BPA, short for bisphenol A, is nearly impossible to avoid. Manufacturers use BPA to harden plastics and apply BPA resin to coat the inside of food and drink cans. BPA is present in water bottles, paper receipts, baby bottles, medical devices, sports equipment, electronics, and countless other consumer goods. BPA resin even coats the inside of water supply lines.

Even people who avoid all contact with known BPA products for a month or more have BPA in their urine. This is significant because the human body clears BPA from its system rather quickly – BPA in the urine indicates exposure within 24 to 48 hours of testing.

BPA mimics the female sex hormone, estrogen, in a way that could be a health hazard. Other studies have linked BPA to many types of cancer, including prostate cancer, in animal subjects.

University of Chicago professor Dr. Gail Prins implanted human stem cells into mice to investigate the association between a male fetus’s exposure to BPA during pregnancy and the risk of developing prostate cancer later in life. The cells, taken from deceased young men, allowed the scientist to measure the effects BPA has on human prostate cells but using animal subjects instead of human ones.

Prins used two groups of mice, both implanted with human prostate tissue. She exposed one group of mice to BPA but did not expose the other group. The scientist introduced BPA through food; the mice ingested a level equivalent to the amount an average person would consume in two weeks.

She then allowed the tissue to mature for one month before exposing the tissue to estrogen. She did this to mimic a man’s natural rise in estrogen as he ages – scientists associate high estrogen levels in males with an increased risk for prostate cancer. Prins then checked the tissue for signs of cancer two to four months after exposure.

Prins found pre-cancerous lesions or fully developed prostate cancer cells in one-third of subjects exposed to BPA. Only one-tenth of the control subjects showed signs of cancer.

The results of the study appear in the medical journal Endocrinology. The author of the study says the U.S. government should act on BPA exposure.

Source: MacGill, Markus. "Pregnancy exposure to BPA in plastic 'raises prostate cancer risk'." Medical News Today. MediLexicon, Intl., 10 Jan. 2014. Web. 20 Jan. 2014.