A new study suggests that every day we are exposed to at least eight times the limit of bisphenol A (BPA) recommended by the U.S. EPA. The new research, published in the journal Environmental Health Perspectives, found that Americans are likely to be exposed at significantly higher levels than previously thought.
BPA is a synthetic estrogen and is commonly used to strengthen plastic and line food cans–scientists have linked it, though not conclusively, to everything from breast cancer to obesity, from attention deficit disorder to genital abnormalities in boys and girls alike.
“This study provides convincing evidence that BPA is dangerous to our health at current levels of human exposure,” said Fredrick vom Saal, Curators’ professor of biological sciences at the University of Missouri. “The new results clearly demonstrate that rodent data on the health effects of BPA are relevant to predictions regarding the health effects of human exposure to BPA. Further evidence of human harm should not be required for regulatory action to reduce human exposure to BPA.”
More than 100 peer-reviewed studies have found BPA to be toxic at low doses, but the FDA says it isnít a threat. Body burden studies show that BPA was detected in 95 percent of the people included in one sampling. “For years, BPA manufacturers have argued that BPA is safe and have denied the validity of more than 200 studies that showed adverse health effects in animals due to exposure to very low doses of BPA. We know that BPA leaches out of products that contain it, and that it acts like estrogen in the body,” said Julia Taylor, lead author and associate research professor at the University of Missouri.
According to Gayathri Vaidyanathan of Greenwire, via The New York Times,† the controversy about it’s adverse health implications hinges on the question: Does the liver detox the chemical completely enough to secrete most of it out in urine, or does BPA get into human blood where it can mimic important hormones?
Thomas Zoeller, a biology professor at the University of Massachusetts, Amherst, notes that BPA has the ability to bind to not one, but three receptors — the estrogen, the male hormone and the thyroid hormone receptors. (My question is, even if the liver does detox BPA, why would we want to consume it anyway, and do our livers really need all of that extra work?!)
“The body evolved to handle stuff that gets into our system — the liver is designed to detoxify,” he said. “There are a range of molecules that are natural, and some are incredible toxins. But when we start to make molecules that are not known to nature, we need to think a little more carefully about how they are going to interact with biological systems.”
Several states, including Connecticut, Massachusetts, Washington, New York and Oregon, have passed bills to reduce exposure to BPA, and similar legislation is pending in the U.S. Congress.