A government panel has concluded that bisphenol A's effects on human reproductive health are mostly minimal, verifying industry experts' contentions and angering environmental groups.
The Aug. 8 report was issued by a 12-person panel of independent scientists. The panel was convened by the Center for the Evaluation of Risks to Human Reproduction, which is part of the National Toxicology Program. The report is the first step toward NTP issuing its final verdict, most likely early next year.
Now that the panel's report is published, NTP will assimilate public comment and issue its own brief. After doing this, NTP has the flexibility to reach a different conclusion, although that is not common.
After a peer review, NTP will publish its brief, the final report and the public comments. NTP has no authority to regulate BPA or to require additional testing, but its findings typically are used by state and federal regulators to set exposure standards.
"What could have been the first opportunity in a decade to advance public health protections for the toxic plastics chemical BPA instead ended in a government advisory panel issuing a final assessment that relies solely on a corrupt process and substandard science, and that fails to support stronger public health safeguards for bottle-fed infants, pregnant women, and other at-risk populations,'' said Anila Jacob, a medical doctor and a senior scientist at the Environmental Working Group in Washington.
In addition, environmental groups such as the New York-based Natural Resources Defense Council criticized the panel for relying largely on oral-dose studies and designating injection-dose studies as having limited utility for assessing human health concerns.
But Steve Hentges, executive director of the polycarbonate/BPA unit of the plastics division of the American Chemistry Council in Arlington, Va., defended the approach used by the panel.
``People are not exposed to BPA through any route except orally,'' where the body converts it into metabolites that are nonestrogenic, he said. ``When you inject BPA'' into an animal, ``it doesn't simulate what happens to the human body because you bypass the normal metabolism.''
That is similar to what a scientific review in Europe of bisphenol A in March found. The review led that group to raise the safe-ingestion level of BPA five times higher than it had established five years earlier.
``There are significant differences in how humans and rodents metabolize BPA,'' the European review concluded.
BPA is used to make PC for products such as baby bottles and medical devices, and to make epoxy resins for coating metal cans for food and beverages.
Specifically, the CERHR panel said there is negligible concern that BPA exposure causes adverse reproductive effects in the general population or, in utero, produces birth defects and malformations. It also said there is minimal concern that exposure to BPA potentially causes acceleration of puberty or, in utero, affects the prostate.
However, the CERHR panel did say it is concerned that exposure to BPA could cause neural and behavioral effects, but advised it will take more research to verify whether that is the case and what those effects might be.