Exposure to BPA May be Too Low to Cause Problems

Tue, 02/19/2013

Pacific Northwest National Laboratory

 

A controversial component of plastic bottles and canned food linings that have helped make the world’s food supply safer has recently come under attack: bisphenol A. Widely known as BPA, it has the potential to mimic the sex hormone estrogen if blood and tissue levels are high enough. Now, an analysis of almost 150 BPA exposure studies shows that in the general population, people's exposure may be many times too low for BPA to effectively mimic estrogen in the human body.

The analysis, presented at the American Association for the Advancement of Science's annual meeting by toxicologist Justin Teeguarden of the Department of Energy's Pacific Northwest National Laboratory, shows that BPA in the blood of the general population is many times lower than blood levels that consistently cause toxicity in animals. The result suggests that animal studies might not reflect the human BPA experience appropriately.

"Looking at all the studies together reveals a remarkably consistent picture of human exposure to BPA with implications for how the risk of human exposure is interpreted," says Teeguarden. "At these exposure levels, exposure to BPA can’t be compared to giving a baby the massive dose of estrogens found in a birth control pill, a comparison made by others.”

In addition to evaluating the likelihood of BPA mimicking estrogen in humans, Teeguarden also analyzed another set of BPA studies that looked at the chemical’s toxicity in animals and cells in the lab. These 130 studies are significant as a group because they refer to the exposures as "low dose," implying they are very relevant to human exposures.

According to his analysis, however, the "low doses" actually span an immense range of concentrations, a billion-fold. In addition, only a small fraction of the exposures in these self-described “low dose” studies are in the range of human exposures, from 0.8 percent to 7 percent depending on the study.

"The term low-dose cannot be understood to mean either relevant to human exposures or in the range of human exposures. However, this is in fact what it has come to mean to the public, as well as many in the media," says Teeguarden.

Analysis of 150 Exposure Studies

The first analysis covered 30,000 individuals, including women and infants, in 19 countries. Human blood concentrations were calculated multiple ways using many kinds of exposure data.

Teeguarden looked to see if BPA concentrations were sufficiently high to be a significant source of estrogen-like activity in the blood. Researchers have long known that BPA can bind to the same proteins that estrogen does – called estrogen receptors – when estrogen is doing its job in the body. However, in most cases, BPA does so much more weakly than estrogen. To trigger biological effects through receptors, BPA concentrations have to be high enough in the blood to overcome that weakness.

"Systematically testing the estrogenicity, or the bioactivity of BPA at the part per trillion concentrations we expect in human blood would seem the most scientific way to substantiate or refute this conclusion," says Teeguarden.

Teeguarden analyzed the data in these studies using multiple independent approaches applied systematically to the data from thousands of individuals. The results showed that human blood levels of BPA are expected to be too far below levels required for significant binding to four of the five key estrogen receptors to cause biological effects.

Teeguarden's analysis also confirmed the findings of many academic and government scientists that biologically active BPA is at such low concentrations in the blood that it is beneath toxicologists' current ability to detect it, raising questions about the role of sample contamination in studies reporting high levels of BPA.

Analysis of 130 Toxicity Studies

In this analysis, Teeguarden compiled all the BPA studies that included the term "low dose" as it referred to human exposure by using such terms as "low-concentration," "environmentally relevant," or "human exposure." From the 130 studies found, he and his PNNL biologist Sesha Hanson-Drury compiled all the doses that were actually used in the studies.

The results showed that a small fraction of the "low doses” used in these studies are within the range of human exposures, with the vast majority being at least 10 to thousands of times higher than what humans are exposed to daily. In addition, the range of concentrations spans from upwards of 10 grams per kilogram of weight per day down to 100 picograms per kilogram of weight per day (a picogram is one millionth of a gram).

"Unfortunately, the low dose moniker has been used by some to promote the importance of selected toxicity studies, for example, in arguments to ban BPA," says Teeguarden. "For BPA and all chemicals, we need more accurate language to present these findings so the public and scientists in other disciplines can understand how human exposures compare to exposures in laboratory studies reporting toxicity.”

What the Sex Lives of California Mice Can Tell You

 

By Alan Caruba

According to Cheryl Rosenfeld, an associate professor of biomedical sciences in the University of Missouri’s Bond Life Science Center, loading up a bunch of California mice with a mega-dose of bisphenol A (BPA) showed researchers that “What we have observed in those models is that BPA affects male rodents differently from females.”

The February 11 UM news release that announced this was titled “Bisphenol A affects sex-specific reproductive behaviors in a monogamous animal species” with a sub-headline that said “Animal findings suggest that gender may also influence chemical risks for humans.”

So, humans are expected to demand that BPA be banned based on the behavior of BPA-besotted California mice, but not the deer mice on which previous similar research was conducted. As noted in the release, “The two rodent species have contrasting mating behaviors.” That’s right, it depends on the sexual proclivities of the species of the mice involved and one has to make a mighty leap of faith that Ms. Rosenfeld’s research applies to humans.

Rosenfeld’s earlier work received notice in a January 2, 2013 Science Daily article which pointed out that, “Following a three-year study using more than 2,800 mice, a University of Missouri researcher was not able to replicate a series of previous studies by another research group investigating the controversial chemical BPA.”

A synopsis of the earlier study noted that “Rosenfeld’s group extended the studies to include animal numbers that surpassed the prior studies to verify their findings were not a fluke and to provide sufficient numbers of animals to ensure that significant differences would be detected if they existed. However, even these additional numbers of animals and extended experiments failed to reproduce the earlier findings.”

It’s worth noting that Ms. Rosenfeld’s later research involving monogamous California mice represented a dose that is a 1,000 times greater than a human would ingest. This research suggests that the anticipated outcome would demonstrate that BPA is harmful.

It reflects a global propaganda campaign to ban a chemical that has been safely in use for fifty years. This campaign is the subject of my six-part series on BPA that can be found at http://thebpafile.blogspot.com/, a blog I maintain that includes other articles on the subject.

As noted on The BPA File, “In 2011, ‘the German Society of Toxicology released a review of more than five thousand previous studies of PBA exposure that concluded that BPA exposure represents no noteworthy risk to the health of the human population, including newborns and babies. Researchers concluded that BPA is neither mutagenic nor likely to be a carcinogen.”

Five thousand studies! At what point does 50 years of safe use to coat the insides of aluminum food cans, protecting the contents against food pathogens such as botulism, put this campaign by environmental groups and others to rest? How many more studies do we need to demonstrate the safety of BPA in making shatterproof safety goggles, DVDs, and scores of other products we use every day?

In March 2012 an Associated Press health reporter, Matthew Perrone, reported that “The Food and Drug Administration has rejected a petition from environmentalists (the Natural Resources Defense Council) that would have banned the plastic-hardening chemical bisphenal-A from all food and drink packaging, including plastic bottles and canned food.” The petition was rejected because the “petitioners did not present compelling scientific evidence to justify new restrictions…”

How compelling is yet another study that involved feeding California mice 1,000 times more BPA than humans would ever ingest? And how would any rational person conclude that alleged changes in monogamous California mice—but not the polygamous deer mice—could be extrapolated to suggest that humans would be affected?

An August 8, 2011 editorial in The Wall Street Journal, “Postscript to a Panic”, noted a study, “financed by the EPA…involved feeding (human) subjects a BPA-rich diet for 24 hours. Researchers then monitored their blood and urine for traces of the chemical” only to find that “the result was BPA levels too low to detect.”

The sheer absurdity of the campaign to get BPA banned reflects a deeper, more sinister agenda by environmental organizations like the Natural Resources Defense Council. It is the belief that the Earth’s human population must be reduced to protect it. Banning BPA would put millions at risk of death from food-borne diseases like botulism.

Given the tenacity with which such groups prosecute their agendas, we can be assured that these obsessed anti-BPA “researchers” aren’t going to go away.

© Alan Caruba, 2013

Dumb and Dumber BPA "Science"

by Angela Logomasini on January 16, 2013

   

Rationalizations to support claims that the chemical bisphenol A (BPA) poses a real and serious health threat have gone from dumb to dumber! Even reputable researchers make their case by regularly citing one inconclusive study to suggest another inconclusive study is meaningful. But science doesn’t work that way.

Used to make hard, clear plastics and resins that line cans containing everything from soda to soup, BPA is a target of the greens who get plenty help from researchers who use creative rationalizations to spin their findings.

A recent example comes from one of the authors of yet another study on BPA using data from the National Health and Nutrition Examination Survey (NHANES). It suggests that BPA levels could contribute to heart and kidney disease. But reliance on NHANES data raises a host of questions about the study’s value, as explained in a prior post and in a peer reviewed paper detailing why it isn’t reasonable to draw conclusions from this data. Without even considering that serious defect, we can see from one of the researchers comments that the study isn’t particularly compelling anyway. One of the study’s authors, Dr. Leonardo Trasande, explains in Science Daily:

While our cross-sectional study cannot definitively confirm that BPA contributes to heart disease or kidney dysfunction in children, together with our previous study of BPA and obesity, this new data adds to already existing concerns about BPA as a contributor to cardiovascular risk in children and adolescents.

In other words, the value of this latest study rests at least in part on the value of the prior study for which Trasande is also an author. This prior study appeared in the Journal of the American Medical Association last year that suggested BPA contributes to obesity, but, as I noted then, the authors say the findings are inconclusive. Specifically, Trasande and coauthors state within the JAMA study:

BPA exposure is plausibly linked to childhood obesity, but evidence is lacking to date … This cross-sectional study, when considered in isolation, is at best hypothesis generating.

Why and how could a study with findings are “at best hypothesis generating” strengthen an “unconfirmed” finding of another study? Supposedly it can because the authors in the JAMA study maintain that it is more than “hypothesis generating” because of findings from yet another study. This one dates back to 2004, and it too is inconclusive, as I detailed in my post on the JAMA study.

Perhaps most telling of all are the studies that Trasnade and his colleagues don’t mention, including a recent rodent study that could not find an association between BPA and obesity. They also don’t mention an EPA-funded study that shows humans pass BPA quickly from the human body — making it unlikely to have any impacts. Nor do they mention, the study questioning the underlying NHANES data.

In sum, ignoring evidence to the contrary, Trasade suggests that his latest inconclusive study is meaningful because of finding of the inclusive JAMA study, which is only made more than “hypothesis generating” because of the existence of yet another inconclusive study.

This very fishy line of reasoning really isn’t about science. It’s about an agenda, as Trasnade explains in Science Daily:

It [his research] further supports the call to limit exposure of BPA in this country, especially in children … Removing it from aluminum cans is probably one of the best ways we can limit exposure. There are alternatives that manufacturers can use to line aluminum cans.

While he may mean well, this advice is the more dangerous proposition because BPA resins are used to prevent the development of pathogens like E. coli in our food. Without it, many people could suffer from real kidney disease, and some could die.

Source: OpenMarket.Org
http://www.openmarket.org/2013/01/16/dumb-and-dumber-bpa-science/?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+Openmarketorg+%28OpenMarket.org%29

NYU School of Medicine Tells Big Lies About BPA

The Dihydrogen Monoxide Award

January 9. 2013 ~ http://hansoffplastics.com

We spend a lot of time and effort ferreting through outrageous media coverage of science issues in determining our Dihydrogen Monoxide Award winners but this time, we’re doing something a little different.

This week’s award goes to the dutiful flacks at the NYU School of Medicine for their January 9, 2013 news release on the results of a study of the chemical bisphenol A (BPA) whose co-lead author is a university researcher. In fairness, we should state that a flack’s job is to get media coverage of whatever it is they’re pushing. However, we don’t think that should include shopping around false information in pursuit media coverage and the January 9 release is chock full of blatantly false information.

Let’s start with this whopper, which nicely sets the stage for whipping the media into a frenzy. It’s a close cousin of the old “banned substance” lie:

“The study adds to the growing concerns about BPA, which was recently banned by the U.S. Food and Drug Administration…”

FACT: The US Food and Drug Administration has done nothing of the sort – ever! As a matter of fact, the FDA has explicitly refused to ban BPA. Oh dear, did the good PR folks at NYU forget that the FDA gave a gigantic smack-down to the Natural Resources Defense Council when the agency rejected the NRDC’s petition to ban BPA? Not very professional, kids. As an antidote for this sort of problem, we recommend reading. It’s very helpful, especially for those interested in facts. Just think of the motto of Faber College – Knowledge is Good.

Apparently not content with promoting the exact opposite position of an American regulatory agency, NYU’s School of Medicine decided to look north and east for new positions to misrepresent:

“Its use has been banned in the European Union and Canada…”

Wow! These guys are just makin’ up stuff left and right! As recently as September 2012, Canada went out of its way to affirm the safety of BPA in food contact applications.

Not only that, but Health Canada also went so far as to note that their position affirming the safety of BPA was the same as policies in the European Union, the United States and Japan!

“… based on the overall weight of evidence, the findings of the previous assessment remain unchanged and Health Canada’s Food Directorate continues to conclude that current dietary exposure to BPA through food packaging uses is not expected to pose a health risk to the general population, including newborns and young children. This conclusion is consistent with those of other food regulatory agencies in other countries, including notably the United States, the European Union and Japan.” (Emphasis added)

As for the European Union, not only has the EU’s food safety body declared BPA safe for use in food contact, it went out of its way to explain why French efforts to ban the stuff are wrong headed.

Whoa, Nelly! How can a guy get so many fundamental facts wrong in ginning up a news release and not get banned from writing future news releases? It’s a mystery to us too.

There there’s the classic “banned from baby bottles,” line. It thrives on misinterpreting the facts:

“Its use has been banned… in the United States for use in baby bottles and sippy cups.”

This is a factual statement. But what makes it such a cheap shot is the fact that the only reason FDA took the action of banning BPA from baby bottles is because it was asked to ban it for that purpose – BY THE PEOPLE WHO MAKE BABY BOTTLES!

Check out this coverage by USA Today. First, we have the headline:

After baby bottle makers voluntarily ban BPA, FDA makes it official

Then there’s the third paragraph of the USA Today article, which we conveniently repeat hear for your review:

“Consumers can be confident these products do not contain BPA,” FDA spokeswoman Shelly Burgess said. She said the agency did not act because it believes BPA is unsafe but because the bottle industry wanted a formal ban for baby products. “We continue to support the safety of BPA for use in products that hold food.”

Let me repeat that: “She said the agency did not act because it believes BPA is unsafe but because the bottle industry wanted a formal ban for baby products.”

See what we mean? The people who make baby bottles stopped using the stuff years ago and asked the FDA to formally ban the stuff, which it did, and in the process the FDA reiterated “… the safety of BPA.”

One thing that was not factually flawed was how the news release tried to make the case for more money for more research. After all, that may be the point here – to use a bunch of false information to create a lot of bad reporting to raise more money so more researchers can increase their prestige and salaries by conducting more research. It’s kind of a vicious cycle, you know?

So congratulations to the cracker-jack flack squad at NYU’s School of Medicine for winning this week’s Dihydrogen Monoxide Award! We give this award four stars. After all, it manages to completely misrepresent the BPA policy positions affecting a score of nations and hundreds of millions of people. It takes a special kind of skill to pull a boner of this proportion.

BPA Studies Alleging Toxicity Unreproduceable

Previous Studies On Toxic Effects of BPA Couldn't Be Reproduced

Jan. 2, 2013 — Following a three-year study using more than 2,800 mice, a University of Missouri researcher was not able to replicate a series of previous studies by another research group investigating the controversial chemical BPA. The MU study is not claiming that BPA is safe, but that the previous series of studies are not reproducible. The MU study, published in the Proceedings of the National Academy of Sciences, also investigated an estrogenic compound found in plants, genistein, in the same three-year study.

"Our findings don't say anything about the positive or negative effects of BPA or genistein," said Cheryl Rosenfeld, associate professor of biomedical sciences in MU's Bond Life Science Center. "Rather, our series of experiments did not detect the same findings as reported by another group on the potential developmental effects of BPA and genistein when exposure of young occurs in the womb."
Creating reliable data on the effects of the chemicals on mice is important to human health since people are frequently exposed to BPA and genistein and humans share similar biological functions with mice. BPA is a chemical used in certain plastic bottles and may be found in the lining of some canned goods and receipt paper. Genistein occurs naturally in soy beans and is sold as a dietary supplement. Research by Fredrick VomSaal, professor of biological science at MU, and others suggests the chemicals may have other adverse effects on many animals, including humans.

Researcher who conducted the original series of experiments claimed that exposure to BPA and genestein resulted in yellow coat color, or agouti, offspring that were more susceptible to obesity and type 2 diabetes compared to their brown coat color, healthy siblings. However, Rosenfeld and her team did not obtain the same results when repeating the study over a three-year period.
After failing to repeat the original experiments findings with similar numbers of animals,

Rosenfeld's group extended the studies to include animal numbers that surpassed the prior studies to verify that their findings were not a fluke and to provide sufficient number of animals to ensure that significant differences would be detected if they existed. However, even these additional numbers of animals and extended experiments failed to reproduce the earlier findings. However, the current studies demonstrate that a maternal diet enriched in estrogenic compounds leads to a greater number of offspring that express an agouti gene compared to those that do not, even though equal ratios should have been born.

"This finding suggests that certain uterine environments may favor animals with a 'thrifty genotype' meaning that the agouti gene of mice may help them survive in unfavorable uterine environments over those mice devoid of this gene, Yet, the downside of this expression of the agouti during early development is that the animals may be at risk for later metabolic disorders, such as obesity and diabetes" Rosenfeld said. "In this aspect, humans also have an agouti gene that encodes for the agouti signaling protein (ASIP) that is expressed in fat tissue and pancreas, and there is some correlation that obese individuals exhibit greater expression of this gene compared to leaner individuals. Therefore, the agouti gene may have evolved to permit humans the ability to survive famine, but its enhanced expression may also potentiate metabolic diseases under bountiful food conditions."

While the research casts doubt on the previous study, Rosenfeld said that by understanding the genetic profile of the mice in the first series of studies, scientists could learn more about the correlation between certain genes and obesity. This could eventually influence prevention and treatment programs for patients with diabetes and other obesity-related diseases in humans.

Web address:
http://www.sciencedaily.com/releases/2013/01/
130102140526.htm

BPA Resubs Replacements May Be More Harmful

BPA resin replacements may be more harmful

By Angela Logomasini, Independent Women's Forum and Competitive Enterprise Institute - 12/27/12 12:00 PM ET – The Hill, Congress Blog

As the year winds down, it’s a good time to look back at what was one of the biggest alarm stories of the year: the alleged health impact of the chemical Bisphenol A (BPA). Were the claims true, and what might we expect to happen in 2013?

In 2012, news headlines were awash with faulty claims about dangers lurking in food, cosmetics, cleaning products, and even cash register receipts — all allegedly posed by BPA. Green groups targeted their message to women, who were — and continue to be--barraged with one-sided stories suggesting that BPA containers pose a serious threat to our children.

These activists claim that BPA is an “endocrine disrupter” — a chemical that affects human hormone systems. Supposedly, it impacts human development starting in the womb and eventually leads to everything from breast cancer, heart disease, obesity, and more. But as IWF scholars have explained many times on Inkwell and elsewhere, women should be wary of such hype.

Manufacturers have used BPA for more than 60 years to make hard, clear plastics and resins that line food containers, and there are no documented cases of BPA-related illnesses from consumer exposures. Research shows that the human body quickly metabolizes and passes out trace-levels of BPA found in food, producing no adverse health effects. Comprehensive studies conducted by researchers from the World Health Organization, United States, European Union, Canada, Japan, and other places have deemed the current uses of BPA safe.

Rather than focus on these comprehensive reviews, greens continue to cite random and largely inconclusive studies that claim to “link” BPA to health problems. But many of these studies are more akin to junk science than hard science as they simply don’t have good data to assess BPA exposures. In fact, researchers highlighted this problem in a recent article in the journal PLOS One.

Nonetheless, governments have already begun taking action on BPA merely to alleviate anxieties generated by environmental activists rather than to address legitimate public health problems. For example, following Canada’s lead, the U.S. Food and Drug Administration banned BPA use in baby bottles and sippy cups this year even though it deemed those uses safe. And the French recently have banned its use in food packaging.

If there is anything to fear, it’s the regulations that may result from the hype. In fact, products that replace BPA may not be any safer and in some cases may be more dangerous.

Ironically, earlier this year, researchers pointed out that the chemical used to replace BPA for plastic baby bottles and reusable water bottles, known as Bisphenol S (BPS), is actually a more potent “endocrine disrupter” and that the human body does not metabolize BPS as easily!

Fortunately, there are many reasons to doubt that trace exposures to BPS — or any synthetic chemical for that matter — could have significant hormonal effects. Synthetic chemicals simply are not potent enough. Consider the fact that natural substances in our diets that we consume every day — such as soy, almonds and a variety of legumes — contain endocrine mimicking” substances that are tens of thousands of times more potent than synthetic chemicals! And we all know, soy and nuts aren’t only safe — they are pretty good for you.

Accordingly while BPS plastic alternatives probably are no more dangerous than BPA, they certainly are not any safer.

Other options are potentially more dangerous. For example, greens suggest glass, but who could seriously deem it safer? We all know the risks associated with broken glass. Indeed, children face far higher risks from cuts and subsequent infections than they do from a trace chemical that has been used for decades without any documented adverse health impacts.

Bans on BPA resins that line cans may pose more serious risks. Specifically, BPA resinsline food containers — from soup to soda cans — to prevent the spread of deadly pathogens like E-coli. Manufacturers pointed out in the Washington Post that there aren’t any good alternatives for this use. Accordingly, bans that force us to buy inferior alternatives may mean increased food-borne illnesses.

Now that’s something to worry about.

Logomasini serves as a senior fellow at the Independent Women's Forum and the Competitive Enterprise Institute.

No BPA Link to Heart Disease

Jon Entine, Contributor

Op/Ed/Forbes

12/06/2012 @ 11:14PM                                               

In Reversal, Bedrock Studies Linking Bisphenol A (BPA) to Heart Disease Challenged

 

Studies supposedly linking the plastic additive to diabetes, heart disease and coronary artery disease have been called a “bombshell” by anti-BPA NGOs and many journalists. Now those conclusions, and a central contention of
campaigners, is in doubt.



The most explosive claim of anti-BPA campaigners—that the plastic additive BPA causes an array of heart-related diseases—is in question, according to a peer reviewed paper on the science website PLOS One.

Environmental health scientist Judy LaKind from Penn State University and the University of Maryland and epidemiologist Michael Goodman from Emory University reviewed data from the National Health and Nutrition Survey (NHANES) that previous researchers concluded linked BPA to chronic diseases. Johns Hopkins mathematician Daniel Naiman did the analysis.

In contrast to those previous studies, which looked at only one, two or three datasets, these researchers found no associations between urinary BPA and heart disease or diabetes across four NHANES datasets. Their conclusions challenge one of the central contentions of researchers who believe that BPA is harmful.
The influence of the NHANES data in creating the popular belief that BPA is harmful cannot be overstated. The controversy originated just a few years ago, when bisphenol A was still a relatively obscure plastic additive that a group of obscure scientists had targeted as dangerously toxic.

Based on controversial studies of rodents injected with the chemical, they had come to believe that BPA was what they called an “endocrine disruptor” that did its dirty work at low doses. It distorted hormonal functions, they claimed, and could be blamed for a host of problems from cancer to reproductive and metabolic issues to heart disease. It was a controversial contention, as toxicity has traditionally been linked to exposure—the dose makes the poison, in Paracelsus’ famous phrase.

Heart disease theory rests on questionable data?

A key turning point in the debate came in 2008 with the release of a study based on the NHANES data covering 2003/4 of nearly 1500 adults in the Journal of the American Medical Association. A team of researchers led by David Melzer, an epidemiologist at the Peninsula College of Medicine and Dentistry at the University of Exeter in the United Kingdom concluded that respondents with higher amounts of BPA in their urine were more likely to report having heart disease and diabetes.

“This is a big deal,” said University of Missouri biologist Frederick vom Saal, the chief proponent of the “endocrine disruptor” hypothesis, who co-authored an
opinion piece that accompanied the study in

 


JAMA. He and John Peterson Myers, a biologist and longtime collaborator, demanded immediate regulatory restrictions on BPA and phthalates, another class of chemicals they contend is dangerous.

The associations were modest, which led the Food and Drug Administration to immediately reaffirm its belief that BPA was safe. But that’s not how it was played in the media and by advocacy NGOs, which flooded the Internet with hundreds of stories “linking” BPA to heart disease. Thousands of articles have since cited the NHANES study as “proof” of BPA’s harmful effects or otherwise casually asserted that BPA is “linked to” or “associated with” chronic heart problems.

After the release of yet another Melzer study based on more recent NHANES data, in 2010, the Natural Resources Defense Council hyperbolically characterized the findings as a “bombshell” as part of its campaign to connect common exposure to everyday chemicals to serious diseases, such as cancer—claims that are not supported by the evidence.

“Health care reform should be linked directly to toxic chemical reform,” wrote Gina Solomon, a scientist and former blogger for the NRDC. “Chemicals such as BPA are a potentially preventable cause of serious illness, and prevention saves lives and dollars.”

Cherry picking data?

The LaKind-Goodman study identified what appear to be two anomalies in the analysis by Melzer and two other related papers released in 2010 and 2011. A diabetes study included as diabetic people who did not have diabetes but had borderline symptoms—a non-standard definition of diabetes. Without those people included, the BPA-diabetes link disappeared.

The heart disease study found a weak association between BPA and heart disease—but it excluded six people who had the highest BPA concentrations. It turns out that none of those left out had heart disease. The inclusion of those respondents would have led to a finding of no association between BPA and serious heart problems. This contentious evidence led to the “bombshell” finding the NRDC crowed about.

The only explanation for leaving out the healthy respondents provided in the Melzer paper is that those excluded were “outside the range of BPA in the original 2003/04 sample,” which topped out at 80.1 ng/mL. According to
epidemiologists I spoke with, they made an odd and arbitrary choice. In a blistering online response to the LaKind-Goodman study they now maintain that the excluded samples, which range from 83.6 to 150, and one outlier at 383, might have been “contaminated.”

In their response, Melzer et al. sharply challenged the overall thrust of the new study, calling it “unfocused” and “poorly documented, and noted that the LaKind-Goodman research was supported by the Polycarbonate/BPA Global Group of the American Chemistry Council. According to the paper, and under the rules of the peer review process, “the ACC was not involved in the design, collection, management, analysis, or interpretation of the data; or in the preparation or approval of the manuscript.”

In more substantive criticism, Melzer said that the new study had left out more than 400 survey respondents, implying those excluded could have skewed the results. LaKind and Goodman wrote they excluded survey respondents who omitted their age, body mass, smoking behavior or other variables to keep the data consistent. Melzer and the primary author of the diabetes study, University of Michigan doctoral pre-candidate Monica Silver, also pointed out that the new study included children in the diabetes assessment, which could also account for the different conclusions. Regardless, responded Lakind and Goodman, they claim they consistently found no associations between urinary BPA and heart disease or diabetes across four NHANES datasets.

Melzer pointedly noted that in a more recent study, published earlier this year, his team found that those who developed coronary artery disease tended to have higher urine BPA concentrations up to ten years earlier than those who did not develop heart disease.

The dispute over the data threatens to obscure the LaKind and Goodman’s most salient conclusion. NHANES is a robust and critically important public health database, they maintain. However, it only measures concurrent exposure to chemicals as reflected in urine, and not long-term impacts.

Limitations of NHANES survey to analyze BPA

“Our results don’t shed light on whether BPA is or isn’t a risk factor for diabetes or heart disease,” said LaKind. “Rather, the point we are making is that using data from cross-sectional studies like NHANES surveys to draw such conclusions about relations between short-lived environmental chemicals and chronic diseases is inappropriate.”

Melzer brushed off that point completely in his response. But Monica Silver, who headed the diabetes study using the NHANES data, emailed me: “I completely agree [with LaKind and Goodman on this point] and make similar conclusions in our paper. NHANES’ utility is not in making broad statements of causation of a given disease by a given exposure, but rather in providing preliminary, hypothesis building evidence that can inform future work.”



Many science-challenged journalists and activist NGOs, like the NRDC and Environmental Working Group that put advocacy ahead of science, consistently misrepresent and hype studies that show the presence of chemicals in urine, as if that signals likely toxic effects. The use of biomonitoring data is problematic, say scientists, particularly as it pertains to BPA. According to the FDA reflecting the emerging scientific consensus, “[O]ral BPA administration [of BPA] results in rapid metabolism of BPA to an inactive [and therefore harmless] form.” In other words, BPA is detoxified and excreted.

That was confirmed in what is considered the state-of-the-art, independent study financed by the Environmental Protection Agency on the potential harm of BPA—headed by Justin Teeguarden, a senior scientist at Battelle’s Pacific Northwest National Laboratory, one of the nation’s premier research centers, to assess how humans process BPA. Their conclusion: Despite the presence of the chemical in urine, human blood concentrations of BPA are infinitesimally low—undetectable in most cases and thousands of times lower than any level that is likely to cause harm to humans.

Although low doses of certain chemicals can induce non-monotonic effects, scientists who have reviewed these studies, time and again, have come away unconvinced these effects consistently or even generally suggest harm. Since 2007, there have been more than a dozen comprehensive reviews of BPA studies by independent government scientists around the world, including in Canada, Europe, Japan, Australia and the United States, and each has concluded that current uses of the chemical are safe.

The European Food Safety Authority in summer 2010, a joint UN Food and Agriculture Organization/WHO expert panel on BPA in November 2010, and a special Advisory Committee of the German Society of Toxicology in spring 2011 have all independently concluded that the collective body of evidence demonstrates that BPA does not pose serious neurological dangers or cause cancer in humans, and has not even been shown to be an “endocrine disruptor,” although it does have modest but not necessarily harmful endocrine effects.
Most recently, in October, Health Canada and that country’s Bureau of Chemical Safety upheld its prior scientific finding that found BPA poses no serious threat. “Based on the overall weight of evidence,” reads the report, “the findings of the previous assessment remain unchanged and Health Canada’s Food Directorate continues to conclude that current dietary exposure to BPA through food packaging uses is not expected to pose a health risk to the general population, including newborns and young children.”

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Jon Entine is senior fellow at the Center for Health & Risk Management and STATS at George Mason University.

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This article is available online at:
http://www.forbes.com/sites/jonentine/2012/12/06/in-reversal-bedrock-studies-linking-bisphenol-a-bpa-to-heart-disease-challenged/