Feb. 3, 2015 -- Are goods labeled “BPA-free” healthier? Maybe not. Two new studies found that some chemicals replacing BPA in plastics, food packaging, and other products might also disrupt hormones, altering brain function and fertility.
In the first study, scientists exposed growing zebra fish to very small amounts of BPA and its chemical cousin called bisphenol-S, or BPS. Zebra fish share 80% of their genes with humans and are often used as a model for human brain development. They are so well-studied that scientists can tell whether the fish are acting normally or not.
For example, in the fish exposed to BPA and BPS, scientists observed bursts of fast swimming and darting with quick turns, which they believe points to anxiety and hyperactivity. The fish that were introduced both chemicals also grew more brain cells called neurons during a critical stage of development, which may explain their behavior. And those exposed to BPS grew more neurons than those exposed to BPA.
In the second study, French researchers exposed small pieces of tissue taken from developing mouse and human testes to BPA and two of its replacements, BPS and bisphenol-F, or BPF. All the chemicals lowered the production of testosterone in these tissues, and BPS proved to be a more potent testosterone-blocker than BPA.
The American Chemistry Council, a trade group that represents companies that make and use BPA and BPS, says it’s wrong to draw conclusions about human health from studies on animals and tissue samples.
The group says in a written statement that “it is well-known that humans, including pregnant women, efficiently convert BPA to a substance with no known biological activity and quickly eliminate it from the body.”
It also says regulatory agencies in the U.S. and Europe have concluded that at the small amounts most people are exposed to, BPA is safe.
The council declined to comment on BPS, though.
For help understanding what all this means, WebMD spoke to Laura Vandenberg, PhD, an assistant professor of environmental health sciences at the University of Massachusetts, Amherst; Cassandra Kinch, a University of Calgary PhD candidate who led the zebra fish study; and Frederick vom Saal, a professor of biology at the University of Missouri who has been studying BPA since the 1970s.
source : Are Products Labeled 'BPA-Free' Safer?
