Jon Entine considers what the rejection of a ban on Bisphenol A, a commonly used chemical, means for business, society, and science-based decision making

The Food and Drug Administration’s decision earlier this month refusing to reverse the Bush Administration and ban Bisphenol A (aka BPA) came as a huge shock for environmental activists openly campaigning for a reversal in government policy.

You may never have heard of BPA but it is one of the most ubiquitous chemicals in the world.

When added to plastic it makes it stronger—hard enough to replace steel and transparent enough to replace glass.

It can withstand high heat and has high electrical resistance.

It can be found in electronics, DVDs, the dashboards of cars, dental applications, even Tupperware.

Because of its incredible flexibility, it’s the key ingredient in epoxy resins and the plastic coating used to line canned goods that protects foods and soft drinks from contamination.

Pressure counts

For months the media had been filled with sensational stories designed to embarrass the Obama FDA, chock full with pro-consumer advocates, into abandoning a 2008 FDA draft finding that the chemical is not dangerous.

My favorite was “BPA Wrecks Sex, Fouls Food––And Probably Worse,” the headline of a Huffington Post piece last November posted by the Environmental Working Group, which has been acting point for a national anti-BPA campaign.

The Milwaukee Sentinel has run no less than 50 reports, and won a bushel of awards, excoriating the government for not restricting BPA’s use.

And last December, Consumer Reports, weighed in, linking BPA to “reproductive abnormalities, heightened risk of breast and prostate cancers, diabetes, and heart disease,” echoing concerns that microscopic particles of the chemical could migrate from sippy-cups into baby’s milk or juice.

It all sounds frightening, scary.

And considering the prior Administration’s history of manipulating science data to support its political agenda on everything from climate research to over-the-counter contraceptives to mercury poisoning, it’s understandable to take these concerns seriously.

That’s why ban proponents were so taken aback when the FDA refused to issue a ban, declaring that BPA posed “negligible” or “minimal” concern for most adults.

Under heavy political pressure to do something to placate the campaigners, the FDA expressed “some” concern for developing fetuses, infants and children.

But when asked directly if they faced any real health dangers, the FDA minced no words: “If we thought it was unsafe, we would be taking strong regulatory action,” said Dr. Joshua Sharfstein, the principal deputy commissioner of the agency.

If the FDA had taken stronger action, it would have come as a shock to regulators in the rest of the world. In just the past few years, BPA has undergone comprehensive reviews and certified as safe in at least 10 industrialized countries.

Most critically, it was declared safe by the European Union in 2006, which is striking because the EU evaluates chemicals using the “precautionary principle”––the controversial notion that environmental policy should be based on the suspected risk of causing harm rather than proof that a substance actually causes harm.

Either there is a massive conspiracy by health and safety officials around the world to cover-up the true story of ‘killer BPA’ or maybe, just maybe, there is a backstory here.

The “novel” hypothesis

For years, ban proponents have challenged established scientific canon about what dose levels of toxic substances are likely to effect humans. It’s called the “new paradigm,” and it grew out of a conference led by the zoologist Theo Colborn, which met in Wingspread, Wisconsin in 1991.

This like-minded group of scientists and activists believed that chemicals—not just BPA—were causing harm in humans that were not picked up by traditional tests. They claimed that while many chemicals such as BPA may not harm people at high doses it might at extremely low doses.

This counter-intuitive claim became known as the “low dose hypothesis” and has been at the heart of the attacks led by EWG and many journalists.

Most scientists remain dubious. According to the FDA report, “studies employing standardized toxicity tests used globally for regulatory decision making thus far have supported the safety of current low levels of human exposure to BPA.”

It did acknowledge, limply, that this “novel” idea does “describe BPA effects” in “laboratory animals,” but the devil is in the details, and the novel experiments are rife with problems.

Only a fraction of studies on BPA indicate toxic or hormonal effects, but at levels 500,000 times higher than humans consume or higher. Most have been on rats.

Animal tests are considered an important first step in evaluating a chemical but by themselves they are of “limited usefulness to human health,” as an article in the British Medical Journal noted recently, because of significant differences in biochemistry, immune systems, and so on.

Most problematically, the novel low-dose hypothesis is based almost entirely on administering BPA to rats by injection, when more than 99 percent of BPA is ingested orally in humans.

That raises two issues. Regulatory agencies don’t put much stock in tests in which a substance is delivered in a different way than how humans experience it.

The European Food Safety Authority, which uses the “precautionary principle” in its deliberations, along with the FDA, the National Toxicology Program, Health Canada–and, in fact, every risk assessment that has systematically looked at BPA––either rejects studies of injected BPA outright or gives primacy to oral studies.

Second, and perhaps the arrow to the heart of the ban proponent’s argument, is that when BPA is ingested orally, as is almost always the real world case, it rapidly detoxifies, first in the gastrointestinal tract and then in the liver. Enzymes add a sugar molecule.

That transforms it into a water-soluble known as BPA-glucuronide, which repeated studies have shown is innocuous, with a half-life of six hours. It’s easily excreted in urine.

In that light, a recent study trying to make hay over the fact that BPA is found in 90 percent of the population, widely circulated by ban proponents and reported without context or qualification by the media—including The New York Times––creates the false impression that the mere presence of it in humans is necessarily something to be concerned by.

The question of whether BPA is harmful ultimately revolves around the murky issue of toxicity. As Paracelsus, the father of toxicology observed, “All things are poison and nothing is without poison, only the dose permits something not be poisonous.”

The world is awash in chemicals, natural and human-made. Many substances found in our foods are toxic, including essential vitamins and minerals, if consumed in large quantities.

The only science-based question is whether a particular substance is harmful at the trace level it is metabolized.

With that in mind, scientists use what’s called risk-risk analysis to evaluate chemicals. They consider two key questions: At what levels could a substance cause harm? And what would be the possible unintended consequences if a useful chemical were pulled off the market?

Some chemicals are both ubiquitous and effective at what they do. BPA falls into that category. It’s been around for more than 100 years.

More than 6 billion pounds of it are produced globally each year, and the market is growing because the need for it is growing. There are no viable alternatives for many of its uses, such as to prevent bacterial contamination, such as botulism, in canned goods.

Consumer concerns, however unproven, about harm from possible leakage into children’s containers has prompted manufacturers to reformulate their infant containers, taking that issue mostly off the table.

The only justification for banning BPA would be if it could be shown, using empirical science and tests on humans, that the hazards and costs outweigh its clear benefits.

Going forward

For those males reading this, who have been anxiously waiting to find out whether they face the prospect of erectile droop, as the EWG, The Los Angeles Times, and other news outlets have alleged, there is good news.

The cited study focused on Chinese workers who handled the chemical in bulk, not with BPA in foods: “the BPA levels these men were exposed to were 50 times higher than that experienced by the average American male in the US.”

The National Toxicology Program, in 2008, reported “negligible concern” that men exposed at non-occupational capacities––in other words men who use plastic containers or consume canned foods––will experience reproductive effects.

Unable so far to prevail on the science in the US debate over BPA, campaigners are already shifting gears from the laboratory to politics.

In January, Minnesota became the first (and still only) state to ban the chemical in baby bottles, basing it on the “precautionary principle,” citing fears of harm.

That same argument prevailed in Canada. In 2008, Health Canada firmly rejected claims that BPA was unsafe. “The current research tells us the general public need not be concerned,” Health Canada declared after reviewing hundreds of studies. “In general, most Canadians are exposed to very low levels of bisphenol A, therefore, it does not pose a health risk.”

But the “precautionary principle” is embodied in Canadian (and EU, but not US) law, which forced Health Canada to ban BPA in baby products even absent convincing scientific evidence.

“Even though scientific information may be inconclusive,” it wrote, “decisions have to be made to meet society's expectations that risks be addressed and living standards maintained.” In April 2008, Health Canada, citing the “precautionary principle,” banned BPA for use in products for infants and children.

It was the first (and still only) restriction on BPA at a national level. Activists next set their sights on Europe, France in particular, which has even stricter precautionary standards.

But in a stunning turn of events, French health authorities rejected the opportunity to follow in Canada’s footsteps. “Canadian authorities banned BPA under public pressure and without any serious scientific study,” said the Minister of Health Roselyne Bachelot during an inquiry at the National Assembly in March 2009.

“The precautionary principle is a principle of reason and under no circumstances a principle of emotion,” she concluded, noting, "it applies when there are no reliable studies. Here, there are reliable studies, which conclude, with current scientific data, that baby bottles containing this chemical compound are innocuous.”

No one is or should be suggesting that BPA is environmentally benign. It is so widely used that regulators should continue to vigorously explore whether its effects on children are serious enough to warrant modifications in policy.

To navigate the complexities of modern society, we need standards and established systems—objective science—to guide us in weighing the benefits and potential hazards of chemicals, drugs, whatever.

But the moment we abandon standards for fashion or under political pressure, no matter how superficially attractive that may seem to be, we place in danger the entire system of checks and balances. We upset that at our own peril.

Jon Entine is a columnist for Ethical Corporation, a member of our advisory board, a visiting fellow at the American Enterprise Institute, and a sustainability consultant.

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