Maybe the journalism consensus has it wrong.
A few weeks ago, a story flashed across my computer screen about bisphenol A, the plastic additive better known by its initialism BPA. European food safety scientists had been asked on an emergency basis to look into a study that it caused brain damage in rodents, and they were releasing their findings. Scary stuff, I anticipated.
I've heard a lot of talk about BPA from my environmentalist friends and in the media, almost none of it good. It's used in all kinds of things: electronics, DVDs, car dashboards, eyeglass lenses and polycarbonate plastics, from microwavable containers to infant sippy cups. It's added to epoxy resins to create dental sealants and to line metal cans to prevent spoilage and botulism. For most of its uses, there are no known substitutes.
It's a hidden killer, my activist friends tell me. I Googled "BPA" and "dangerous" and got 273,000 hits. The Los Angeles Times, Consumer Reports, Fast Company and innumerable other information sources cite "hundreds" of studies claiming it wreaks havoc with our hormonal system, causing neurological problems and breast cancers, autism, diabetes, ATD. . . you name it, if it's a common disease it's mentioned in some report or another as linked to BPA.
Surfing the web, I found an incendiary quote from an animal neurobiologist named Frederick vom Saal at the University of Missouri, who appears to have staked his entire career on the premise that BPA is harmful to humans. "The science is clear and the findings are not just scary, they are horrific," he says. "When you feed a baby out of a clear, hard plastic bottle, it's like giving the baby a birth control pill." That's not the way scientists usually talk. I gaze at my daughter drinking a Gatorade, and the label gradually morphs into a skull and cross bones.
So, I was a little shocked when this article came across the transom. It noted that scientists with the European Commission had looked at more than 800 studies on BPA and came away unimpressed by the clamor to ban it. They concluded that the research to date has "many shortcomings" and is generally not relevant to human health. What about brain cancer, the subject of a BPA study released earlier this year, which created such a stir in the media? The EFSA concluded there is no "convincing evidence" of BPA's neurobehavioral toxicity.
At first, that didn't make sense. This is the E.U. Aren't regulators guided by the precautionary principle, the "better safe than sorry" standard that leads to restrictions of chemicals all the times when there is even just a hint of a potential threat, even absent evidence of actual danger?
A blogger for The Atlantic, a nutritionist and professor at New York University, Marion Nestle, who hates BPA from what I can see from her writing, apparently read the same story and came away unmoved and a little ticked that those pesky scientists and regulators were challenging the consensus that BPA is the 'world's most dangerous commonly encountered substance'. "Aren't you reassured by this (e.g. the EFSA exculpation of BPA)," she sneered.
It didn't seem from what she wrote that she had even read the EFSA report, but I guess she has a point. After all, haven't Canada, France and Denmark all banned BPA in products used by children? Yes, they all did. But something doesn't seem right here either. I looked into the Health Canada review first. The chief scientist, and head of the study, Mark Richardson, said BPA's impact was "so low as to be totally inconsequential." He compared its estrogenic effects to tofu. It turns out that dozens of natural substances known as phytoestrogens, including soy products, nuts, seeds, berries, bourbon and even beer have the same effects on the human endocrine system as does BPA, and often with higher levels of exposure. (Uh oh, I hope no one recommends banning beer.)
All hell broke loose after Richardson made those comments. The Toronto Globe and Mail and some environmental NGOs helped fuel an attack on his independence and got him reassigned, even though he had no industry connections and has an impressive CV. A month later, the Health Canada report came out, sans Richardson, but it repeated all his key conclusions, albeit in less colorful language. It concluded: "Bisphenol A does not pose a risk to the general population, including adults, teenagers and children."
If there is no risk, why were restrictions slapped on infant baby bottles? Canada has the precautionary principle in effect, and its version of it requires regulators to issue restrictions even without evidence that kids are in danger. "[D]ecisions have to be made to meet society's expectations," Health Canada writes.
I'm getting a little nervous about this 'fulfilling societal expectations' thing. On the 100th anniversary of Darwin's birthday last summer, a Gallup poll showed that less than 40 percent of Americans believe in evolution. I look over at my daughter again, imagining her, in this brave new world where societies expectations about science are fulfilled, designing a diorama about evolution for science class, with Adam and Eve staring down a tyrex and a pack of velociraptors. And she'd get an "A." Maybe we should think twice about subjecting science issues to a popular vote.
What about France and Denmark? Here's where my daughter really came in handy; she speaks French. She translated some stories for me that we found on the web. Apparently, French scientists were (and are) steadfast against a ban voted into place by the French Parliament. "Canadian authorities banned BPA under public pressure and without any serious scientific study," said Minister of Health Roselyne Bachelot during an inquiry at the National Assembly. "The precautionary principle is a principle of reason and under no circumstances a principle of emotion," Bachelot 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."
So French politicians did what politicians do in such situations and capitulated to outraged NGOs to 'fulfill societal expectations' by banning BPA in kids products, ignoring its own scientists' recommendations. Denmark restricted it too, reacting to a study published earlier this year that linked BPA to neurobiological problems in rodents. Those are the findings that prompted the E.U. to take up the issue again this summer in an emergency review. They assessed the new data and concluded--how do I put this diplomatically--that the study was lame.
What do U.S. authorities say about BPA? I consulted my consumer activist friends again. They're disconsolate. Last February, the Food and Drug Administration reviewed the data for the second time in two years. Everyone expected the agency to ban it, but it didn't change a thing, just ordered up more expensive studies, authorizing $30 million in stimulus funds. When asked directly if adults or children faced any genuine health dangers, Joshua Sharfstein, M.D., the FDA's principal deputy commissioner, minced no words: "If we thought it was unsafe, we would be taking strong regulatory action."
Although the FDA again refused to recommend that BPA be restricted, I've been told on the hush that the situation might change soon. The Obama inner circle hasn't yet been able to wrest control of the agency from all those career scientists, who apparently are in hock to industry. A few Congress people have proposed sidestepping the science to do what they think society apparently wants, which according to some NGOs is to ban that terrible chemical. They call their bill, "The BPA-Free Kids Act." Catchy and smart linking it to children.
I thought about what I had been finding, and was perplexed. Maybe all these scientists in the U.S. and Canada and Europe that have reviewed more than 800 studies and have concluded that BPA is safe are in the pay of industry? I read an article on this debate on the venerable Huffington Post by David Ropeik, a journalist who lectures at Harvard on risk issues. That's what he believes. In a recent post, he made it sound like this issue is a shoot out between what he called "industry experts [who] seem sure it is [safe], and environmental health experts [who] seem pretty sure it's not."
But that can't be right. If that were true, then every independent science advisory board in every major industrial country would be on the take. Yet not one has recommended that it be banned. The scientists (as distinguished from political boards) reviewing the BPA studies in North America, Europe, Australia, New Zealand and many countries in Asia have all concluded it's safe as used.
It seems that most scientists, at least among toxicologists, believe there's not much there there. A survey of 937 toxicologists by the non-partisan watchdog group STATS at George Mason University found only 9 percent rated BPA as a serious health risk, about one-third the number who thought sunlight was a danger.
The Milwaukee Journal Sentinel, which has won a bushel of awards for its reporting on BPA bestowed on it by organizations run by fellow journalists who have also written critically about BPA using the same sources that independent science boards find wanting, criticized the study, claiming that toxicologists were the wrong ones to talk to. Toxicologists generally embrace the maxim of the Renaissance scientist Paracelsus usually written as "the dose makes the poison." As a group, they're likely to be highly suspicious of the central claim of BPA ban proponents who endorse what the FDA calls the "novel hypothesis"-- that low doses of BPA can have more effect on the human endocrine system than high doses.
It's a controversial notion, but it's not without some possible validity We just need to figure out, using empirical and replicatable science, what those effects might be--in humans. The hypothesis does have some traction among some endocrinologists as well as some geneticists studying how hormone mediators, like BPA or soy or beer, can effect gene expression--what's called an epigenetic effect. Of those who consider the notion plausible, I have found none, outside of vom Saal and a literal handful of others, who believe with real confidence that BPA is harmful to humans. Mostly they just have worries based on crude, small scale, rodent studies
To get to the bottom of this, I began reading over some of the hundreds of studies published over the past decade on BPA. They break down into two major categories that I think helps explain why the controversy is so contentious, even among scientists, and why journalists keep misreporting this issue.
On the one side you have university researchers who are hypothesis-driven: academicians who have organized studies asking targeted questions designed to challenge existing paradigms--in this case, the belief that BPA is safe at very low exposure levels. Because it's easier and less costly, they almost administer BPA by injection directly into a rodent's gut, which is not the way humans ingest it, I'm fairly certain.
Study after study, including by the Centers for Disease Control, has reported that BPA is degraded in the stomach when taken orally. By injecting BPA into the rodents, the chemical is not metabolized as fast, which means it's more likely to show effects. University scientists who have signed petitions demanding that BPA be banned insist nothing nefarious is going on here, it just happens that the studies that don't find problems administer BPA the way humans take it and those that find problems involve injecting rats, and I believe them.
There have been more than a hundred of these smaller scale studies, many finding one adverse effect or another. The problem is that they often conflict with each other. For example, while one may show sperm count of the rats is down, prostate weight is up, testis weight is up, and male fertility is unaffected, another study shows just the opposite on all counts. Both show "effects," but there is no reproducibility. I bet you can count on one hand the number of journalists who have actually read most or all of these studies, as I have. Take a look. It'll open your eyes.
But the media and their NGO pals treat those studies quite differently than regulators do. They write sensational accounts with shocking headlines, such as "BPA Wrecks Your Sex Life," for a story written by the Environmental Working Group, which has relentlessly targeted BPA going on four years now. An article on the latest study might then mention there were two studies, both of which indicated effects--it might say, for example, that one showed sperm count down and another showed testis weight down. Aha! Look at the reproductive problems BPA causes, an Internet posting would note. Never mind that the reports conflict. They just add up the number of studies that showed one effect or another, which doesn't tell you much.
Regulators see it differently. They don't put much stock in these hypothesis-driven studies unless large-scale analyses confirm a consistent pattern. To most credible scientists, small studies are scientific noise until a larger pattern stands out. In the case of BPA, it hasn't. The state-of-the-art studies that follow Good Laboratory Practices and upon which the EFSA, the FDA and other regulators rely have shown few consistent effects from BPA. In these studies, BPA is administered orally, which is another reason why regulators consider them more seriously. That's the background explanation behind the European Union's rejection of the Stump study, which set off alarm bells that led to the EFSA summer review of BPA. The Stump study, now discredited, was the central reason why the Danish government issued its ban.
The government sometimes mandates larger GLP studies, and industry is required to fund them. Of course, that presents an easy target for critics, including activist academics, NGOs and journalists, although there is no evidence that any "industry-funded" data involving BPA has been manipulated or compromised. But between you and men, who really believes they are really independent.
To me, it looks like a clash of cultures between academic research scientists, who are testing new hypotheses and regulatory scientists, who must weigh a range of risks and unintended consequences before enacting or changing regulations. The university scientists depend on research grants to fund their work, but they insist that provides no incentive to find problems even though their research dollars would dry up if BPA turned out to be as benign as most scientists now suspect. Personally, I think university scientists have high moral standards and would rather shut their labs down and go on unemployment than research something that doesn't need to be looked into anymore.
Some endocrinologists who had jumped onto the low dose bandwagon years ago are now bailing. Richard Sharpe, head of the Centre for Reproductive Biology at the Medical Research Institute in Edinburgh and a recognized pioneer on the effects on endocrine disruption, with no industry ties, was an early adaptor. He now suggests in a recent article in Toxicological Sciences that hundreds of millions of dollars have been squandered on what was a once-legitimate scientific inquiry but is now an obsession. The large-scale studies have ended the uncertainty. BPA is harmless.
Sharpe has no axe to grind. He does note that two studies show an association of BPA with certain liver disorders, which after reviewing the data he believes is diet related (drinking sugary drinks from bottles and cans whose interior is lined with resin containing the chemical). Sugar, he says, is far more harmful than BPA. Wow.
"Just apply common sense. If several studies using the human-relevant route of exposure show no effect but a small preliminary study does show effects, which would you believe?" he writes, unwilling to take a strong stand. "The overwhelming scientific evidence says that bisphenol A is not a risk to human health."
You may not have seen Sharpe's comments in your local newspaper, on the Internet, in Consumer Reports or in the New York Times, or even on Fox News. After all, we live in a 'bad news, all the time' world. What else did they miss? Two major U.S. government supervised studies released over the past nine months blow holes in the low dose hypothesis. A team led by L. Earl Gray, Jr. at the EPA's Research Triangle center in North Carolina found the alleged "endocrine disruptor" so weak that even at levels of exposure 4,000 times higher than the maximum exposure of humans in the general population, "BPA did not display any estrogenicity."
Researchers working under the direction of Daniel Doerge, a chemist at the FDA's National Center for Toxicological Research in Arkansas and a staff member on the EPA Science Advisory Board, concluded that the miniscule trace levels of BPA we ingest are efficiently metabolized and do not accumulate; newborns and infants metabolize and excrete the substance, rendering it harmless within a day or two; and rodents injected with BPA exaggerate the potential to humans.
Two distinguished FDA toxicologists, Ronald Lorentzen and David Hattan, have been so disgusted by what they believe is "biased" reporting by journalists who seem to have a personal stake in the low dose notion, wrote an unprecedented and scathing letter to Nature, which had written an unsigned editorial about the controversy:
. . .[S]afety regulation depends upon scientific consensus. Of course, this does not mean unanimity. Yet, without a consensus over the state of science for a particular issue, there is no end in sight to the claims that can be made for which a consensus does not exist. To abandon this conceptual objective for any temporary, subjective, personal convenience is a formula for a general regulatory impasse. . . . [T]he BPA episode has revealed the general inexperience of many in the experimental scientific community to the intricacies of risk assessment and the necessity of employing risk management judgments in any comprehensive determination of human safety. In spite of their lack of familiarity with this model for a thorough, balanced process, many have gone to notable measures to make public safety admonitions on the basis of studies that were not designed to provide consensus answers to, in this case, the integrated function of an intact endocrine system.
As Lorentzen and Hattan point out, university scientists who advocate for a ban have been free to lobby the press on behalf of their views while government experts and industry scientists face tight restrictions on their freedom to speak out. Without any regulatory responsibilities, the critics have created the false impression, echoed by the media, that a "growing consensus" exists among most scientists that BPA is dangerous.
Well, they've had their day. Maybe it's time to consider our obligations to society and not just try to meet the often-low expectations of the masses. No creationism please. I've tried to take a time capsule view of this controversy. As professor Richard Sharpe suggests, it's hard to escape the thought that the "low dose endocrine disruptor" hypothesis has now been around for more than 15 years, and yet still remains a notion in search of consistent data.
Oh yes. . . just in case you were wondering, BPA doesn't "wreck" your sex life. . .
Jon Entine is a visiting fellow at AEI.