Bisphenol A (BPA) in high quantity can harm people, just like almost anything. BPA has been labeled a concern by some because of its ability to be an endocrine disruptor that hijacks the normal responses of hormones.
While toxicology studies have shown that only very high doses of this chemical affect exposed animals — doses as high as 50 mg/kg/day - by focusing on numerous endpoints a new review says it can find effects not detected in peer-reviewed toxicology studies. The authors of a new paper conclude that endocrine disruptors need to be studied at much lower doses.
To revise the threat risk for BPA, the group looked at hundreds of recent studies and added their own integrative biological approach to scrutinize low dose effects of BPA at multiple levels of biological organization: on cells, animals and human populations. After looking at "low dose" literature, they say they can find reproducible effects in animals after exposure to incredibly low doses of BPA - ten to forty times lower than the doses identified in toxicology studies. Several dozen of the "low dose" studies they found claim effects of BPA at doses that humans are thought to encounter in their everyday lives.
They say that BPA exposure, both in vitro and in vivo, contributes to a large range of health problems in humans, such as polycystic ovarian syndrome, immune response to allergens, behavioral problems and decreased fertility. The effects on wildlife were also widespread in their review.
Will it hold up? BPA is certainly at DDT and alar levels of hysteria - and reviews are only as good as the material being reviewed. The authors went out of their way to review studies finding problems with BPA, which lacks a valid null hypothesis, and it's published in Endocrine Disruptors. Their confidence notwithstanding, BPA needs to be examined carefully before it is vilified more.
Endocrine Disruptors September 30, 2013