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Aug. 15, 2008 -- Bisphenol A, the controversial plastic chemical, is safe at typical exposure levels from food and drink, according to an FDA?draft report.
Bisphenol A, also called BPA, is found in polycarbonate plastic, including some water bottles and baby bottles, and in epoxy resins, which are used to line metal products including canned foods.
The draft report states that based on lab tests in rodents, infants and adults are exposed to bisphenol A?levels that are below toxic levels. "Safe or safety means that there is reasonable certainty in the minds of competent scientists that the substance is not harmful under the intended conditions of use,"?but "complete certainty of absolute harmlessness is scientifically impossible to establish," the draft report states.
Bisphenol A safety became a hot topic in April, when U.S. government scientists at the National Toxicology Program (NTP) expressed "some" concern about bisphenol A's possible effects on the mammary gland, prostate gland, and accelerated female puberty.
Since then, there's been a storm of bisphenol A publicity, with major retailers including Wal-Mart backing away from baby bottles containing bisphenol A, the FDA probing bisphenol A safety, and consumers wondering how concerned they should be.
"It's become a bit of a media spectacle," says Sarah Vogel, PhD, MPH, whose Columbia University dissertation traces the politics, economics, and scientific history of bisphenol A.
That spectacle hasn't let up. Today's FDA?draft report, which doesn't recommend banning bisphenol A, is the latest development. But California lawmakers are debating a bill that would limit bisphenol A to trace amounts in products for kids age 3 and younger, and the NTP's final report is?expected this summer. An?FDA?subcommittee will meet on?Sept. 16 to discuss the FDA's draft report on bisphenol A.
But will those reports settle the bisphenol A safety debate? Or have the questions lodged in the public consciousness, with opinion outpacing official guidance? And when all is said and done, will you ever look at your water bottles, baby bottles, and canned foods the same way?
It depends whom you ask, with three very different viewpoints vying for your favor.
This is the stance that the European Food Safety Authority (EFSA) took in late July -- and it's in line with today's FDA?draft report.
An EFSA panel reviewed bisphenol A research -- mostly done on rodents -- and concluded that bisphenol A passes through the human body much faster than in rodents, with little chance for harm to human fetuses or newborns.
That finding "supports FDA's position that data we have reviewed up until this time support the safety of the currently permitted uses of BPA in food contact material," FDA spokesman Sebastian Cianci told WebMD?by email last week, before the draft report was issued. Like the European report, the FDA's draft report argues that studying bisphenol A's effects in rodents may "overestimate"?bisphenol A's effects in humans.
The American Chemistry Council, a plastics industry trade group, praises the FDA's conclusion. In a news release, the council says the FDA's draft report "strongly reaffirms"?the safety of bisphenol A and calls the draft report "the most up-to-date analysis on the safety of bisphenol A in the world."
Steven Hentges, PhD, of the American Chemistry Council's Polycarbonate/BPA Global Group, told WebMD?last week that consumers and companies that ditched bisphenol A made those decisions "very quickly, without having complete and final information."
Hentges says the studies that touched off concern "really aren't very robust." He also sees a "language" issue dating back to the NTP's draft report.
"The NTP language was 'some concern' and people tended to focus on the word 'concern' without realizing or really thinking through that there's a qualifier up front: 'some,'" says Hentges.
People with concerns about bisphenol A -- including some scientists studying bisphenol A -- see no proof that bisphenol A is harmless in humans.
Vogel, who will start a fellowship at the nonprofit Chemical Heritage Foundation in Philadelphia this fall, favors banning bisphenol A, but she doesn't think that a ban is likely.
Earlier this week, Vogel told WebMD she?expected the FDA?would, "at a minimum, would decide to reduce the reference dose," which is the acceptable amount of bisphenol A exposure in everyday life. That didn't happen; the FDA's draft report doesn't mention changing the reference dose.
Vogel wasn't immediately available to comment on the FDA's draft report. The nonprofit Environmental Working Group -- which Vogel doesn't work for -- issued a news release criticizing the FDA's draft report. "We have long since lost faith in FDA's ability to be an impartial authority on FDA's safety. Time and again, FDA?has sided with special interests instead of the public interest on this chemical,"?Renee Sharp, a senior analyst with the Environmental Working Group, says in the news release.
Almost 93% of Americans have detectable levels of bisphenol A in their urine, Vogel observes, citing CDC data on urine samples provided by some 2,500 Americans aged 6 and older for a national health survey in 2003-2004.
Those CDC figures don't connect bisphenol A to health effects. But the data, along with bisphenol A research on animals, "doesn't make me feel great," Vogel says. She'd like to see stricter safety standards and more research in people, as long as research doesn't become a stalling tactic. "If it's a way to delay any decision on BPA, it's really frustrating," says Vogel.
Hentges counters that "with bisphenol A, we already know so much about it ... it's not likely that anyone's going to do an experiment tomorrow that will render everything that we know today wrong."
Canadian health officials took what they called a "prudent" approach in April, when they proposed banning bisphenol A in baby bottles, although their risk assessment didn't find proof of danger.
"Canada really took the lead and said this is what the precautionary principle looks like," says Vogel. "It will be interesting to see how it plays out."
Hentges stresses the fact that the Canadian proposal isn't law yet and isn't based on science. "If you dig into the details of the science, you find that they're really quite similar -- Canada, NTP... Europe. None of them found those studies to be really compelling, none found them to be really suitable for making any kind of real conclusion."
Meanwhile, Vogel says the bisphenol A issue goes beyond baby bottles and water bottles. She's concerned about bisphenol A in the environment, workers who handle bisphenol A, and the government's chemical safety standards and risk assessment process.
"These are really big issues," says Vogel. She sees a larger tug of war between people's desire to "do what's right" and to be reassured that "everything is fine."
What to do in the meantime? Here's what the FDA told consumers in April, when the media frenzy began. It's advice that focuses only on baby bottles, not other sources of bisphenol A.
"At this time, FDA is not recommending that anyone discontinue using products that contain BPA while we continue our risk-assessment process. However, concerned consumers should know that several alternatives to polycarbonate baby bottles exist, including glass baby bottles."