Cap's Off of Plastic Chemical Concerns
Government Scientists Voice Concern About Bisphenol A, but Stop Short of Making Recommendations
April 15, 2008 -- Government scientists today weighed in on possible health
risks linked to the plastic chemical bisphenol A -- and in some cases, they
note higher risk than their advisory panel.
That news comes amid media reports that Canada's government may soon
classify bisphenol A as a dangerous substance. The chemical, found in
polycarbonate plastic, is used in a range of food containers, from baby and water bottles to the
resins that line metal food cans.
Today's U.S. report doesn't go that far; it doesn't make any recommendations
about bisphenol A. What the report does say is that government scientists have
"some" concern about bisphenol A's effects, while a previous
report voiced "minimal" concern about those potential effects.
"We're certainly not out to alarm people," Michael D. Shelby, PhD,
director of the National Toxicology Program's Center for the Evaluation of Risk
to Human Reproduction, tells WebMD.
"If people are concerned about it, there are ways they can reduce their
exposure to bisphenol A, and if they feel it's necessary they should take those
steps," says Shelby, who headed the group of government scientists that
issued today's draft report.
What the Report Found
Today, the NTP posted a draft of its own report on bisphenol A. It based its
findings in part on research conducted by an expert panel for the NTP that was
last year along with new scientific research published since the expert panel did its work, and
public comments on the expert panel's review.
Shelby says while they largely agreed with the expert panel, which was
convened by the Center for the Evaluation of Risk to Human Reproduction, they
broadened the areas they felt could be of "some" concern, including
effects on the mammary gland, prostate gland, and acceleration of puberty in females.
Both groups agreed that there already was some concern that exposure to the
chemical could cause neural and behavioral effects in fetuses, infants, and
The evidence -- which came from studies on rodents, not people -- was
"very limited," Shelby says. "But our conclusion was that we
couldn't dismiss the possibility that similar effects might occur in
"This is a very controversial area with obvious differences in the way
different groups have interpreted the data," Shelby says. "We have
tried to do it in as scientifically sound and thorough means as we
"Even in the areas where we've expressed some concern, the literature is
not consistent on the endpoints reported," Shelby continues. "Some
people find these effects; others may not, and their relevance to effects on
human health -- there's still some uncertainty about that. That's why we didn't
have a lower or higher level of concern in our conclusions."
The draft brief is posted on the NTP's web site. The NTP is taking comments
on the brief, which will be reviewed by other scientists in June.
Shelby expects to issue the final version of the NTP's brief on bisphenol A
in late summer. But that report won't include any rules on BPA's use. "We
are not a regulatory agency," Shelby says.