This new study, published online in the journal Endocrinology, is an advancement on previous BPA research using rats and mice, and shows that tiny BPA doses can throw prostate development into a tailspin, setting the organ up for precancerous prostate epithelial neoplasia (or PIN) and prostate cancer.
BPA is found in many No. 7 plastics, along with thermal cash-register receipts and the lining of most canned foods and drinks. The mass-produced chemical is detected in most Americans, too—not too surprisingly, considering its wide range of uses.
In the latest study, scientists used human stem cells from an organ donor to grow human prostate tissue, allowing it to mature to a PSA-producing state. They then transplanted it into host mice. The researchers found that exposure of the human prostate tissue to low-dose BPA during the crucial developmental phase significantly increased the risk that the tissue developed prostate cancer down the line. "Exposure to BPA during early development appears to predispose the human prostate tissue to neoplasia and cancer with aging," explains study author Gail S. Prins, PhD, professor of urology and physiology at the University of Illinois at Chicago.
Researchers used low-dose BPA exposure on par with what Americans experience every day, measuring levels of BPA in the blood using ultrasensitive new methods.
BPA is so problematic in the human body because it acts like a synthetic form of estrogen. "The prostate gland, as a reproductive organ in the male, is a direct target for estrogen action," Prins explains. "Estrogens can drive prostate diseases, including prostate cancer. These facts have been known for decades."
Her teams' new research shows that BPA activates rapid actions in the human prostate. In fact, some unpublished findings suggest BPA reprograms the stem-like cells, giving them increased sensitivity to the carcinogenic actions of estrogens throughout life, Prins explains. "Simply put, BPA exposure produces an amplifier effect, setting into motion an increased sensitivity to later-life rising estrogen levels, as occurs in aging men," she adds.
So what should people do? For starters, avoid BPA-containing products as much as possible, particularly women who are pregnant or with young children. (They are developing, and exposure could set them up for disease later in life.) Many researchers, Prins included, say people can urge their local, state, and federal governments to demand more industry transparency about BPA presence in their products. People can also advocate for BPA bans.
Prins says there is clear proof that as prostate cancer cells mutate, they can be directly stimulated by BPA, which enhances their growth and spread. "So I would caution men diagnosed with this disease to also make attempts to avoid contact with BPA," Prins says.
To avoid BPA, don't drink or eat out of plastic containers, avoid canned food, choosing fresh or frozen instead, and say no to trivial cash-register receipts.
For more on how BPA ruins your health, read 5 Weird Things BPA's Doing to Your Body.