When the FDA draft report for peer review came out on Feb. 26, 2018, claiming that BPA was safe, the Endocrine Society and academic scientists were up in arms. Not only did they dispute the findings, but they challenged the release of a draft for peer review prior to the peer-review process occurring.
"It is premature to draw conclusions based on the release of one component of a two-part report," said Endocrine Society spokesperson Laura N. Vandenberg, Ph.D. "The National Toxicology Program draft report released Friday included the results of one government study with a partial data set and has yet to undergo peer review."
Notwithstanding the curious nature of the release, this EPA position is not new. In fact, it’s long-standing. The EPA has remained consistent in its view since its initial draft study in 2008 to its publication of literature reviews from 2011 to 2014.
Vanderberg's work is at the heart of the challenge to this EPA draft for peer review. Her focus has been on how traditional toxicology assays have failed to identify a number of ubiquitous endocrine disruptors, and how current risk assessment practices can be improved in both the study of and the regulation of this class of chemicals.
Her research has concentrated on how low doses of endocrine disrupting plasticizers—chemicals that can alter how cells and tissues grow during critical windows of development can lead to adult diseases such as cancer, obesity, and infertility. The FDA draft directly targets the conclusions of her work.
Plastic Pollution Coalition (PPC) recently concluded a pilot study, ReThink Plastic, funded by the California Breast Cancer Research Fund (CBCRF), in partnership with Child Health and Development Studies (CHDS), a project of The Public Health Institute. The results of the pilot's intervention showed that participants changed their behavior after learning of the risks of exposure to chemicals like BPA that mimic estrogens in the body.
Some readers may be familiar with how long the tobacco industry fought against the health hazards of smoking. Casting doubt on the science continued for decades despite the 1964 Surgeon General’s report highlighting the deleterious health consequences of tobacco use.
EWG's Senior Policy Analyst Sonya Lunder wrote an article in 2015 which clearly explained the conflict. She describes the fight over BPA safety fundamentally as a fight over the science of endocrine disruption. These facts have not changed today:
The strong political influence of the North American Metal Packaging Alliance.
The fact that the science of endocrine disruption has upended many traditional scientific notions of toxicity in which even low concentrations of these chemicals can have effects on the developing brain, nervous system, and reproductive systems of people, laboratory animals, and wildlife.
In the 1996 publication of Our Stolen Future, Theo Colborn and her colleagues alerted the public to a growing body of evidence demonstrating the widespread exposure to a dangerous mixture of chemicals that changed hormone signaling, with possibly ominous effects on the health of humans and other animals. They called for urgent investigation into the effects of these chemicals, which led to advanced research methods that documented that hormone-disrupting chemicals were responsible for subtle but permanent changes in the brains, behavior, and reproductive systems of humans and animals, even in concentrations of a few parts per billion.
The FDA continues to be unwilling to accept the massive body of evidence based on the work of Colborn et al. They still focus on traditional methods of studying chemicals for toxicity which focus on the amount of a chemical that will cause gross organ and tissue damages, or imitate cancer, and work backwards to a supposedly non-toxic—non-poisonous—amount.
What Colborn and her colleagues found was that chemicals that might kill cells at high doses, behaved paradoxically at low doses, stimulating cell growth.
In 2009, the Endocrine Society, summed up the new and surprising insights into endocrine-disrupting chemicals: "…even infinitesimally low levels of exposure—indeed, any level of exposure at all—may cause endocrine or reproductive abnormalities, particularly if exposure occurs during a critical developmental window. Surprisingly, low doses may even exert more potent effects than higher doses."
Research linking endocrine disrupters to abnormal cell changes and cell growth led to connections between these chemicals and cancer, early puberty, infertility, prostate enlargement, and other reproductive system disorders, obesity, cardiovascular damage, brain function, and many other ills.
Given the FDA's reliance on old scientific methods, it's not news that the agency won’t budge from its position that BPA is not toxic at the levels to which humans are exposed in everyday life.
What is most curious is why the FDA, a partner in a multi-year, multi-million-dollar research initiative called CLARITY-BPA with the National Institute of Environmental Health Sciences along with more than a dozen academic researchers, would upstage its own research findings and not follow accepted peer-reviewed science protocols.
The CLARITY project's aim was for a comprehensive evaluation of the reproductive and developmental effects of BPA in laboratory animals. Its focus was to evaluate sensitive markers of hormone disruption to the breast, prostate, brain, and other body systems and to scrutinize the effects of the chemical at range of different doses.
The current FDA announcement is the draft result of The CLARITY group's research. It’s based on the results of a comprehensive two-year rodent study examining the potential effects of BPA on health over 90-days in 2014. The study concluded that no low dose effects of BPA were found.
However, Lunder notes methodological problems from the pilot study where control animals were unintentionally exposed to low doses of BPA. That would make drawing any conclusions about the safety of everyday BPA exposures for Americans impossible to assess. Frederick S. vom Saal's 2006 report describes the complexity of issues with human versus animal studies on BPA, supporting the health risks from low BPA exposure for humans.
Why has the FDA issued a safety announcement based on a flawed, short-term study before the massive CLARITY-BPA study has been completed? One can only guess, but Lunder believes the science of endocrine disruption has become a political issue similar to the previous fight over the health hazards of tobacco. We know where that led. (To learn more, read Merchants of Doubt.)
Why does it matter?
It matters because BPA is an environmental health risk that can be avoided. In health care, the common thread is to do no harm and to err on the side of safety. That means reducing exposure risks to chemicals that disrupt natural body functions. In the case of BPA, such risk has been demonstrated across the scientific literature. However, the results are complicated and there is a pre-existing Catch-22. Human subject protocols cannot do the same kind of testing that is allowed with animals and hence, human experimental studies are not ethically possible. Naturally the producers of those chemicals don’t want consumers to take this position, but we all have a choice.
As PPC’s lead research investigative partner on the ReThink Plastic pilot study, Dr. Barbara Cohn notes, "This pilot study demonstrates that a short term education program can significantly influence behavior change to reduce exposure to this class of chemicals when participants change their habits for food preparation, selection, and storage habits."
More testing needs to be done, however, consumer awareness is critically important to force change by manufacturers. It is noteworthy that In many instances, companies have already transitioned away from BPA, substituting another form of bisphenol, BPS. However, consumers beware—BPS has also been shown to be just as hazardous.