"Safe" doses of BPA impact reproductive health

Another week, another scientific study finding bisphenol A (BPA) may have adverse impacts on our health. This week another study reported that exposure to low doses of BPA had significant reproductive health effects, including early onset of puberty.

A study released this week by Dr. Heather B. Patisaul at North Carolina State University and the National Institute of Environmental Health Sciences found that exposure to BPA at levels the EPA has determined are safe resulted in early onset of puberty, which is a known risk factor for breast cancer and other mental and physical health problems.

Data also show higher levels of exposure to BPA can lead to significant ovarian malformations, including cysts that likely indicate infertility.

The drumbeat of concern from the scientific community about BPA is getting louder.  Earlier this week, SaferStates reported on a study linking BPA to heart arrhythmias in women.  Environmental Health News  (EHN) has a list of 109 important scientific studies on BPA that challenge the industry's contention that current levels of BPA exposure are safe.

A sample of recent studies shows that BPA does not leave the body as quickly as thought; BPA may increase breast cancer risk in rats exposed through their mother’s breast milk; BPA exposure in the womb causes infant male monkeys to behave more like infant female monkeys; and exposure to estrogenic chemicals including BPA, disrupts specialized brain cells and their ability to regulate brain chemistry.

Industry’s response to the growing scientific evidence of adverse health impacts from BPA exposure has been to encourage its pundits to write off the studies as “junk science,” blame the media for flawed and unfair coverage, and accuse advocacy groups of “regurgitating” theories from the “bible of chemophobia.” (Mercifully we missed the memo about regurgitating.)

But one memo we didn’t miss was the notorious Cosmos Club memo, which details the plans of BPA chemical makers and canners to use “fear tactics” and proactive communications to convince moms and legislators that BPA is safe to consume.

As mom bloggers have made clear, those tactics aren't going to change their minds about the risks from BPA to their families.

What's becoming truly alarming about the resistance of industry to acknowledge the problem with BPA is the sense that they are clinging to old, failing tools to determine the safety of chemicals that disrupt hormones at low levels. Dr. Pat Hunt, a geneticist at Washington State University, made a key distinction between the use of toxicology versus endocrinology to determine harm in an interview with Scientific American.  

But according to Hunt, treating BPA like a traditional toxin is dangerous because it “doesn’t play by the rules.” Standard toxicology states that if a chemical is bad, “then higher doses are worse and an even higher dose is even worse,” Hunt explains. But with hormones (and estrogen mimics like BPA), she says, high doses can sometimes “shut down” the body’s response, and low doses are enough to exert effects.

We need a new system to regulate dangerous chemicals like BPA. Congress, are you listening?