BPA Plastic 

A new study is out on the safety of plastic bottles. BPA (bisphenol A) is found in much of our food packaging, particularly plastic bottles with the recycling number 7. More than 90 percent of Americans have trances of BPA in their bodies, but the FDA insists that it is not enough to pose a significant health risk. However, a recent study released by the American Medical Association paints a different picture.

Read more about the safety of BPA plastic here:

Study links common plastics chemical to heart woes

REUTERS article published on 9/16/08
By Will Dunham

A major study links a chemical used in many plastic products including baby bottles to human problems such as heart disease and diabetes, while U.S. regulators on Tuesday said they still believe it is safe.

The chemical bisphenol A, or BPA, is widely used in plastic food and beverage containers and in the coating of food cans.

Until now, environmental and consumer activists who have questioned the safety of BPA have relied on animal studies. But the study by British researchers in the Journal of the American Medical Association found that among 1,455 U.S. adults, those with the highest levels of BPA were more likely to have heart disease, diabetes and liver-enzyme abnormalities than those with the lowest levels.

U.S. Food and Drug Administration officials said they would review the new findings, which were not taken into consideration when the agency issued a draft conclusion in August that BPA is safe at current exposure levels.

"We have confidence in the data that we've looked at and the data that we're relying on to say that the margin of safety is adequate," FDA official Laura Tarantino told reporters at a meeting of experts advising the agency on its BPA conclusions.

"There are things you can do if you choose to reduce your level of bisphenol A," Tarantino said. "But we have not recommended that anyone change their habits or change their use of any of these products because right now we don't have the evidence in front of us to suggest that people need to."

BPA is used to make polycarbonate plastic, a clear shatter-resistant material in products ranging from baby and water bottles to plastic eating utensils to sports safety equipment and medical devices.

It also is used to make durable epoxy resins used as the coating in most food and beverage cans and in dental fillings. BPA can mimic the hormone estrogen in the body.


LEACHING INTO LIQUIDS

People can consume BPA when it leaches out of plastic into liquid such as baby formula, water or food inside a container. Some retailers and manufacturers are moving away from products with BPA. Canadian officials concluded BPA was harmful.

Steven Hentges of the American Chemistry Council, a chemical industry group, said the study's design did not allow for anyone to conclude BPA causes heart disease and diabetes.

"At least from this study, we cannot draw any conclusion that bisphenol A causes any health effect," he said.

"On the other hand, though, bisphenol A has been very intensively studied in a very large number of laboratory animal studies. And the weight of evidence from those studies ... continues to support the safe use of products containing bisphenol A," Hentges said in a telephone interview.

The British researchers, who acknowledged their findings are not proof that the chemical is causing the harm, analyzed urine samples from a U.S. government health survey of adults ages 18-74 representative of the U.S. population.

The 25 percent of people with the highest levels of bisphenol A in their bodies were more than twice as likely to have heart disease, including heart attacks or type 2 diabetes, compared to the 25 percent with the lowest levels.

At the FDA panel meeting, several scientists and activists said the FDA ignored animal studies finding health concerns and some called for it to be banned in food container products.

Senior Democratic U.S. Rep. John Dingell of Michigan, who heads the House Committee on Energy and Commerce, said the FDA has "focused myopically on industry-funded research."

Tarantino said nothing was ignored but industry-funded studies finding no harm were important in the conclusions. The panel is expected to present its advice to the FDA next month.

Tarantino, head of the FDA's office of food additive safety, said there is talk of government scientists doing their own BPA safety studies. Such work could take years to conduct, however.

Health Effects of BPA Plastic

Bisphenol A is an endocrine disruptor: it is an estrogen receptor agonist, and such agonists can act like the body's own hormones, leading to similar physiological effects on the body. There is thus concern that long term low dose exposure to bisphenol A may induce chronic toxicity in humans.

Recent studies suggest it may also be linked to obesity by triggering fat-cell activity and have confirmed that bisphenol A exposure during development has carcinogenic effects and produce precursors of breast cancer. However, neither the U.S. Environmental Protection Agency nor the International Agency for Research on Cancer have evaluated Bisphenol A for possible carcinogenic activity. Most recently, a study by the Yale School of Medicine demonstrated that adverse neurological effects occur in non-human primates regularly exposed to bisphenol A at levels equal the EPA's maximum safe dose of 50 µg/kg/day.

In 2007, a consensus statement by 38 experts on bisphenol A concluded that average levels in people are above those that cause harm to animals in laboratory experiments, and a panel convened by the U.S. National Institutes of Health determined that there was "some concern" about BPA's effects on fetal and infant brain development and behavior. A 2008 report by the U.S. National Toxicology Program (NTP) agreed with the panel, expressing "some concern for effects on the brain, behavior, and prostate gland in fetuses, infants, and children at current human exposures to bisphenol A," and "minimal concern for effects on the mammary gland and an earlier age for puberty for females in fetuses, infants, and children at current human exposures to bisphenol A." The NTP had "negligible concern that exposure of pregnant women to bisphenol A will result in fetal or neonatal mortality, birth defects, or reduced birth weight and growth in their offspring."

In April 2008, Health Canada released its Draft Screening Assessment for bisphenol A, which concluded that the chemical may pose some risk to infants and proposed classifying the chemical as "'toxic' to human health and the environment." This action follows Canadian regulators selection of bisphenol A in 2006 as one of 200 substances deserving of thorough safety assessments because preliminary studies had found it to be "inherently toxic"; the chemical had not previously been studied by them in depth, having been accepted under grandfather clauses when stricter regulations were passed in the 1980s.

In contrast to the recent actions in North America, in January 2006 the German Federal Institute for Risk Assessment announced that polycarbonate baby bottles are safe and stated that published research on the health effects of Bisphenol A is "difficult to interpret and [is] occasionally contradictory". An assessment released later that year by the European Union’s Food Safety Authority reached a similar conclusion, expressing "considerable reservations" about the biological significance and robustness of the low-dose exposure studies on rodents. In 2007 Japan also concluded that for individuals in that country, "the current exposure levels of BPA will not pose any unacceptable risk to human health [and] that a ban is not needed."

Some toxicologists and regulatory agencies have criticized low-dose toxicity studies, especially those that involved injecting bisphenol A directly into animals, since human exposures typically involve ingestion and subsequent metabolism in the liver, and the experimental design of a few of these early studies has also been questioned. On the other hand, studies have also appeared pointing out flaws in chemical industry funded studies that found no evidence of adverse effects from low dose exposure, and a study from 2008 concluded that blood levels of bisphenol A in neonatal mice are the same whether it is injected or ingested.

The FDA defends plastic linked with health risks

Associated Press article published on 9/16/08
By Ricardo Alonso-Zaldivar and Lindsey Tanner

With scientists at odds over the safety of a chemical found in plastic baby bottles, metal cans and other food packaging, consumers got minimal guidance Tuesday about how to protect themselves.

At a scientific hearing, the Food and Drug Administration defended its assessment that bisphenol A_ or BPA_is safe, even as the first major study of health effects in people linked it with possible risks for heart disease and diabetes. The debate could drag on for years.

"Right now, our tentative conclusion is that it's safe, so we're not recommending any change in habits," said Laura Tarantino, head of the FDA's office of food additive safety. But she acknowledged, "there are a number of things people can do to lower their exposure."

For example, consumers can avoid plastic containers imprinted with the recycling number '7,' as many of those contain BPA. Or, said Tarantino, they can avoid warming food in such containers, as heat helps to release the chemical.

More than 90 percent of Americans have traces of BPA in their bodies, but the FDA says the levels of exposure are too low to pose a health risk, even for infants and children.

However, a study released Tuesday by the Journal of the American Medical Association suggested a new concern about BPA. Because of the possible public health implications, the results "deserve scientific follow-up," the study authors said. Using a health survey of nearly 1,500 adults, they found that those exposed to higher amounts of BPA were more likely to report having heart disease and diabetes.

But the study is preliminary, far from proof that the chemical caused the health problems. Two Dartmouth College analysts of medical research said it raises questions but provides no answers about whether the ubiquitous chemical is harmful.

FDA officials said they are not dismissing such findings, and conceded that further research is needed. "We recognize the need to resolve the concerning questions that have been raised," said Tarantino. But the FDA is arguing that the studies with rats and mice it relied on for its assessment are more thorough than some of the human research that has raised doubts.

The FDA has asked an outside panel for a second opinion on its BPA safety assessment, and the medical journal article was released to coincide with the advisers' hearing.

The FDA has the power to limit use of BPA in food containers and medical devices but last month released its internal report concluding that BPA exposure is not enough to warrant action.

Since then, another government agency released a separate report concluding that risks to people, in particular to infants and children, cannot be ruled out.

Past animal studies have suggested reproductive and hormone-related problems from BPA. The JAMA study is the largest to examine possible BPA effects in people and the first suggesting a direct link to heart disease, said scientists Frederick vom Saal and John Peterson Myers, both longtime critics of the chemical.

Still, they said more rigorous studies are needed to confirm the results.

Vom Saal is a biological sciences professor at University of Missouri who has served as an expert witness and consultant on BPA litigation. Myers is chief scientist at Environmental Health Sciences, a Charlottesville, Va., nonprofit group. They wrote an editorial accompanying the JAMA study.

BPA is used in hardened plastics in a wide range of consumer goods including food containers, eyeglass lenses and compact discs. Many scientists believe it can act like the hormone estrogen, and animal studies have linked it with breast, prostate and reproductive system problems and some cancers.

Researchers from Britain and the University of Iowa examined a U.S. government health survey of 1,455 American adults who gave urine samples in 2003-04 and reported whether they had any of several common diseases.

Participants were divided into four groups based on BPA urine amounts; more than 90 percent had detectable BPA in their urine.

A total of 79 had heart attacks, chest pain or other types of cardiovascular disease and 136 had diabetes. There were more than twice as many people with heart disease or diabetes in the highest BPA group than in the lowest BPA group. The study showed no connection between BPA and other ailments, including cancer.

No one in the study had BPA urine amounts showing higher than recommended exposure levels, said co-author Dr. David Melzer, a University of Exeter researcher.

Drs. Lisa Schwartz and Steven Woloshin of the Dartmouth Institute for Health Policy and Clinical Practice said the study presents no clear information about what might have caused participants' heart disease and diabetes.

"Measuring who has disease and high BPA levels at a single point in time cannot tell you which comes first," Schwartz said.

The study authors acknowledge that it's impossible to rule out that people who already have heart disease or diabetes are somehow more vulnerable to having BPA show up in their urine.

The American Chemistry Council, an industry trade group, said the study is flawed, has substantial limitations and proves nothing.

But Dr. Ana Soto of Tufts University said the study raises enough concerns to warrant government action to limit BPA exposure.

"We shouldn't wait until further studies are done in order to act in protecting humans," said Soto, who has called for more restrictions in the past.

An earlier lab experiment with human fat tissue found that BPA can interfere with a hormone involved in protecting against diabetes, heart disease and obesity. That study appeared online last month in Environmental Health Perspectives, a monthly journal published by the National Institutes of Health.

Government toxicology experts have also studied BPA and recently completed their own report based on earlier animal studies. They found no strong evidence of health hazards from BPA, but said there was "some concern" about possible effects on the brain in fetuses, infants and children.

Several states are considering restricting BPA use, some manufacturers have begun promoting BPA-free baby bottles, and some stores are phasing out baby products containing the chemical. The European Union has said that BPA-containing products are safe, but Canada's government has proposed banning the sale of baby bottles with BPA as a precaution.