New BPA Study

Because endocrine disruption is a big part of our experience with toxic mold exposure, we have steered away from plastics in our home. This is because of the use of BPA (bisphenol A), a compound known to warp the reproductive systems of mice.

The controversy surrounding BPA took a new twist this month when a new study published in the journal Environmental Health Perspectives concluded that total daily human exposure occurs via multiple routes and is much higher than previously assumed. Dr. Frederick vom Saal, endocrinologist and one of the study's seven authors, believes it's time for Congress to act. According to vom Saal, "If you set the bar at proof of harm to humans, you have failed to protect the public health."

The study examined both mice and rhesus monkeys, the latter selected because they are good predictors of how the human body absorbs this type of chemical. Eighteen hours after exposure, the monkeys' blood still contained active BPA.

BPA is everywhere, with the CDC concluding that more than 90 percent of Americans are chronically exposed. Vom Saal calls the levels "nothing short of insanity" and compares today's use of BPA to the use of lead in paint a century ago.

According to an article appearing this month in The Atlantic, vom Saal has devoted the last 13 years of his life to the issue of BPA and plastics.

In the late '90s, vom Saal and his colleagues in the University of Missouri's Endocrine Disruptor Group were the first to show BPA's possible danger. BPA acts like estrogen, something scientists have known since 1936, but no one knew its potential harm until 1997. Vom Saal and his fellow researchers discovered how the chemical warped the reproductive systems of mice, enlarging prostates and reducing sperm counts.

Those initial studies slowly caused an international furor, and the studies multiplied. Vom Saal published more than 30 papers on BPA himself, and he became a spokesman for the plastic's dangers, traveling across the country to testify before legislatures and talk to national media. This September, he won a Heinz Award, worth $100,000, for his contributions to the BPA debate.

The velocity of the debate sped up during the last two years. The National Toxicology Program found "some concern" with the chemical in September 2008, a concern mirrored by the FDA this January 2010 and the EPA in March. The scientific progress has been "astounding," vom Saal says, and has helped usher in a new paradigm of toxicology, one that works with endocrinologists in entirely new ways. The "total disconnect" between toxicology and endocrinology was, vom Saal explains, how BPA was misclassified as safe. Animal studies have linked BPA to health problems including unusual brain chemistry, obesity, attention disorders, breast cancer, prostate cancer, and premature puberty. A 2008 cross-sectional study with 1,500 humans found a significant correlation between BPA levels in urine and heart disease.

The most recent study indicates that past rodent data may, in fact, be a compelling predictor of how BPA harms humans, now that the effects of BPA have also been observed in rhesus monkeys and shown to harmonize with prior data. If the study's conclusions are valid, then the effects of BPA may actually be far more serious than anything we feared in the past. It also removes another shred of doubt about BPA's safety in a debate conflicted with varying methodologies, a great deal of money, and heated emotions.

Vom Saal supports a green chemistry solution, blending the sensibilities of public health and chemistry to ensure any replacement for BPA is safe. He points to Japan, which successfully phased out BPA a decade ago with little trouble.

With 8 billion pounds of BPA produced annually, industry has had a profound impact on the debate, which has stalled the passage of the national food safety bill throughout 2010. Yet vom Saal seems certain that there will be a day of reckoning. The companies know the hazards, he believes, and eventually court cases will confirm this. We also need to know what products contain BPA, he says—information we currently lack.

The full article can be viewed here.

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