COLUMBIA — Over the years, the rise in obesity, heart disease and some cancers have been attributed to our food and drink intake. Routine visits to fast food drive-thrus for cheeseburgers and greasy fries clog our arteries. Not enough exercise and too many Little Debbies round out our tummies. But the use of Bisphenol-A, a chemical found in hard plastics and metal food cans, has significantly altered a contemporary cliche: It's not just what you eat, it's what you eat out of.
"This poses a threat," MU scientist Frederick vom Saal said of Bisphenol-A. "This will shorten lives."
Bisphenol-A, also known as BPA, is an estrogen-like chemical used in many polycarbonate plastics. Polycarbonate plastics are the hard, see-through plastics used to make products such as baby bottles, reuseable water bottles and sippy cups.
The chemical also lines the inside of metal food cans. From canned sodas to canned corn to canned soup, anyone eating or drinking from cans is exposed to BPA. The chemical leaches from plastics and cans, according to the U.S. Food and Drug Administration. Studies have linked BPA exposure to obesity, heart disease and cancer, vom Saal said.
Vom Saal routinely compares BPA to tobacco and the cigarette companies' efforts to not have cigarettes labeled as detrimental to public health.
"They're going to end up like the tobacco companies, sued into the Stone Age," vom Saal said of BPA supporters.
Vom Saal has studied BPA since 1995. He is recognized as a premiere source of data on BPA. His research has been published in scientific journals and magazines, such as Nature, and he has testified in Washington, D.C., at hearings of the FDA. For more than a decade, vom Saal has publicly denounced BPA as a toxin and threat to public health.
The FDA, however, refuses to take any precautionary steps to reduce the public's exposure to BPA. In September, the agency declined to act on BPA, even though Canada took steps in April to reduce child exposure to BPA. In December, the FDA decided to compile more research on the chemical's effects.
BPA now floats in a state of limbo. Researchers argue that the chemical should be banned right away and that the FDA has acted without the public's interest in mind. Manufacturers of BPA, however, say opposing scientists lack proof that BPA causes disease.
Where is BPA?
Many day-to-day items are made of or use polycarbonate plastic, such as eyeglass lenses, CDs, helmets and computers, according to Bisphenol-A.org, a Web site of the American Chemistry Council. Because people don't eat out of helmets or these other items, the risk of exposure to BPA is not high. Research has shown that the greatest danger is BPA in food containers.
Baby bottles made of polycarbonate plastic leach BPA when heated. The scare lies in the amount of BPA contamination that occurs when babies drink warmed milk from these bottles. Plasticware, when heated, leaches BPA as well. And other plastic drinking products, such as sippy cups and reuseable water and sports bottles, leach BPA over time, whether they are heated or not.
Big name supermarkets, such as Walmart, have offered BPA-free baby bottles, with plans to offer only BPA-free baby bottles early this year.
Clover's Natural Market on Chapel Plaza Court phased out all polycarbonate water bottles in the past spring, Nellie Boyt, store team leader, said. Instead, the store carries stainless steel water bottles and BPA-free plastic bottles. Clover's also only sells BPA-free baby products, including teething rings.
The BPA-free water bottles sell at about the same rate as the polycarbonate bottles, Boyt said. And every week, she said, about three to four customers specifically request BPA-free baby products.
Boyt, who tries to avoid BPA herself and has even kicked her microwave to the curb, lamented that canned goods contain BPA. She hopes the U.S. implements a way to eliminate the chemical in canned goods.
"I'm excited to see BPA-free canned foods," Boyt said. "Like wow."
BPA protects canned food from contamination from the metal, but in exchange contaminates the food, according to the nonprofit Environmental Working Group.
In March 2007, the group published its results on BPA in canned foods. The organization found that infant formula, ravioli and chicken soup contained the most BPA. One to three servings from any of the three had enough BPA to do harm, as reflected in previous animal studies, according to the group's Web site.
Research by vom Saal showed that BPA leached more in canned acidic foods, such as tuna. "Anything with tomato is a nightmare," he said.
In Japan, manufacturers switched to an ethylene lining for canned foods to avoid BPA contamination, vom Saal said. He says the U.S. should follow the Japanese and Canadian examples of reducing public exposure to BPA.
When comparing BPA levels in 2007, the Centers for Disease Control and Prevention found that people with the least income had more BPA in their systems than those with the highest income. Canned foods tend to be cheaper and easier than buying fresh or frozen.
Mike DeSantis, marketing director at the Central Missouri Food Bank, did not know how many canned goods were donated and turned over to recipients, but the BPA worry was not a worry of his.
"Our biggest concern is feeding hungry people, and we follow to the letter of the law every guideline," he said.
Another source of BPA is from recycled paper products. Vom Saal said that BPA has been found in carbonless recycled paper and store receipts.
"When you order pizza in a recycled paper box, you're being impregnated with Bisphenol-A," vom Saal said.
The science on Bisphenol-A
The CDC found that in 2007, 93 percent of the people they tested for BPA exposure had various levels of the chemical in their urine. Those with the highest levels were children.
The National Toxicology Program under the National Institutes of Health also concluded that BPA posed some danger. In its September report, it cited "some concern for effects on the brain, behavior and prostate gland in fetuses, infants and children at current human exposures to Bisphenol-A."
A June 2007 study published in the journal Reviews in Endocrine and Metabolic Disorders linked diabetes to BPA. Bisphenol-A mimics estrogen, and high levels of estrogen in the body increases the body's sugar production, which can lead to diabetes and heart disease, vom Saal said. Rodent studies show that BPA stores itself in fat, and those with more fat deposits carry more BPA, he said.
No one should think that genetics, high-calorie foods and exercise no longer play a major role in heart disease and related illnesses. They do. But vom Saal says BPA worsens the situation. He has also found that when all other factors are equal, BPA causes breast cancer and early puberty in animals.
A study published in September in the Journal of the American Medical Association showed the strongest link between human intake of BPA and health effects. Of 1,455 people age 6 and older, those with the highest levels of BPA in their urine "were more than twice as likely to report having cardiovascular (heart) disease or diabetes" and "higher BPA levels were associated with clinically abnormal liver enzyme concentrations," according to the study briefing.
The writers, scientists from the University of Exeter, U.K., and University of Iowa, based their findings on data collected by the CDC's 2003-04 National Health and Nutrition Examination Survey. The study is the first large-scale look at BPA effects in humans, but it does not conclusively find that BPA causes heart disease or diabetes.
The FDA has used the lack of hard proof as a reason to decline to take drastic action on the chemical.
Much of the research on BPA tested animal exposure to the chemical. As of August, 218 animal test studies on BPA effects were published, according to vom Saal's research. About 86 percent, or 189 studies, found BPA negatively affected animals. About 13 percent, or 29 studies, found that BPA did not harm the test animals. Vom Saal says the chemical industry financially backed research that found no harm due to BPA.
The American Chemistry Council did not return numerous requests for an interview, but on its Web site stated that "the common ground we all share is a commitment to do what’s right to protect the health and safety of American consumers —adults and children alike.” BPA is safe at current normal exposure levels, according to the chemistry council.
The FDA reviewed the mass of research on BPA and agreed with the council. In August, the FDA's Science Board released its review of the BPA literature. It stated: "FDA has concluded that an adequate margin of safety exists for BPA at current levels of exposure from food contact uses."
But in October, the FDA's Science Board Subcommittee on Bisphenol-A looked over the Science Board's shoulder. The subcommittee, staffed by seven doctorates, concluded that the board's August report fell short of being reliable. The group released its own report, recommending that the FDA further examine BPA in infant formula and BPA effects in newborns.
The subcommittee also said it thought the FDA needed to lower exposure levels of BPA the agency previously cited as safe: "... The Margins of Safety defined by FDA as 'adequate' are, in fact, inadequate."
The politics of BPA
In the 1950s, commercial manufacturing of BPA took off, and by 2003, the world used about 3 million metric tons of BPA, according to Bisphenol-A.org. That translates into lots of dollars for BPA manufacturers.
Missouri ranks 16th in chemical industry employment with more than 18,000 jobs, according to the American Chemistry Council Web site. In addition, more than 900,000 jobs are dependent on chemical products, making up about 33 percent of all Missouri jobs. The council estimates that more than 172,000 of those jobs are in the intermediate goods industry, which includes plastic products. In dollars and cents: More than $36 billion in earnings depend on the chemical industry, according to the council's Web site.
A dependency on the chemical industry may be playing a role in the controversy over BPA. Vom Saal has accused the FDA of using studies backed by the chemical industry to defend its position.
"The FDA has become an agency that is treating regulated corporations as clients," vom Saal said. "And that is exactly what it looks like is happening with Bisphenol-A."
The FDA did not respond to numerous requests for an interview.
Current agency officials may be on their way out, though, come Jan. 20. President-elect Barack Obama's transition team has expressed an interest in the future of BPA.
"We've heard from the Obama transition team and the spokespeople from Obama that they are very interested in restoring integrity, not just in the FDA, but across agencies," said Renee Sharp, a senior analyst for the Environmental Working Group.
Sharp hasn't been guaranteed a new BPA policy by the Obama team, but she hopes for one. She disagrees with current BPA policy and accused the FDA of politicization and malfeasance.
"Our basic reaction is that it is outrageous," said Sharp, who has worked for the Environmental Working Group for eight years. "It's sad evidence of the state of the FDA right now. We've seen the last few years of more and more instances of them falling down on the job."
Two bills, one introduced in the House and the other in the Senate, look to do what the FDA has not.
The Ban Poisonous Additives Act of 2008 lists BPA in food containers as “a poisonous or deleterious substance which may render the contents injurious to health.” The Senate bill, BPA-Free Kids Act of 2008, wants to ban BPA in products meant for children 7 years old or younger. The bill has been referred to the Senate Committee on Commerce, Science and Transportation, of which Sen. Claire McCaskill is a member. McCaskill declined numerous requests for an interview. Votes on both bills are expected this session.
It will be up to Congress and the Obama administration to determine whether the law and FDA rules on BPA need revising. Anticipation of the BPA debate heating up looks very likely in the coming months.
"We've heard quite a bit from the Obama people that they definitely want to see a different world in terms of one that follows the science," Sharp said. "But it's really impossible to say what we can expect. The leadership is certainly key, but at the same time ... what you can get is somewhat sort of a captured agency , where the agency has been captured by the industry and there is some worry that that is what's happened with the FDA."
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