Bisphenol A (BPA), a weak synthetic estrogen used in a variety of consumer products ranging from baby bottles to resins that line food and beverage containers, has been linked in some studies to adverse health effects in rodents, including obesity, cancer and insulin resistance.
There is growing concern that the chemical may cause similar adverse effects in humans, particularly in babies and young children.
But there are vast discrepancies in the findings of government-funded and industry experiments that have explored the health effects of BPA, according to an opinion piece article scheduled for the April 16 issue of Chemical & Engineering News (C&EN), ACS? weekly newsmagazine.
Among government-funded experiments on lab animals and tissues, 153 found adverse effects and 14 did not, the magazine reports. The majority of those that reported no harm were funded by chemical corporations, the story notes. C&EN senior editor Bette Hileman highlights a number of potential sources of bias behind these inconsistent study outcomes, including the use of strains of rats that are insensitive to estrogen and choosing batches of animal feed that vary widely in their estrogenic activities.
Bias is even evident in the National Toxicology Program?s assessment of BPA, the writer notes. A panel chosen to review the data was selected with help from Sciences International, an outside contractor with ties to two BPA manufacturers. The panel?s review omitted critical studies and misclassified some of the studies, according to the article. Only an unbiased panel with appropriate expertise can resolve apparently conflicting results of these health studies, Hileman says.