In the wake of the Sigg/bisphenol-A controversy, a top researcher and CEO of Environmental Health Sciences fills us in on the news: endocrine disruptors such as BPA and phthalates are indeed toxic at low-level doses, too. And they’re toxic in entirely different ways than at the traditional high-dose testing indicates.
The way the tests work today is we think that by testing at high doses we’re gonna see everything. So that once we get to a dose that’s intermediate and we don’t see anything, we’re golden.
But the science is telling us that at really low doses as contaminants mimic hormones. They can have effects that are totally unpredictable by what happens at high doses.
Pete Myers spoke to Living on Earth about the consequences of current testing.
We know that by describing a chemical as “endocrine disrupting”, we are saying that it interferes with the normal function of hormones in some way. Currently, the popular notion is that chemicals are only problematic at high doses. After all, we are exposed to a variety of toxins daily and have been our whole lives. That whole, “And I turned out fine” line of thinking. But what does “fine” describe?
What hormones and these contaminants do is at very low doses they turn on and off genes. Genes are being turned on and off trillions of times a second throughout your lifetime. And the orchestration of that is absolutely vital to life. If the genes get turned on or off at the wrong time, that’s gonna lead to a problem. You’re gonna lack a protein that might be important for example in suppressing a tumor or in controlling the growth of your heart.
And the body’s control system for these genes is designed to function at really, really low levels… We’re talking parts per trillion to parts per billion to low parts per million.
Recently, news also came out that there is, indeed, still bisphenol-A in those “BPA-free” baby items. Those who reported it, like myself, were given a hard time by some companies for bringing the study to light. No, the BPA was not put there deliberately. Yes, we are exposed to it via numerous avenues. And yes, the BPA in the Health Canada study is at trace amounts, as ZRecs reported soon after.
But what if a “trace amount” is still harmful?
More research clearly needs to be done at low doses, especially contaminants like phthalates and BPA. Dr. Myers says that while the EPA is finally taking the first steps to investigate these chemicals, this stuff is big business. Especially BPA:
You do the calculation and it’s worth about $800,000 an hour. You can buy a lot of lawyers to defend your product with $800,000 an hour in revenue. But BPA is the poster child of this low dose debate.
Image: Shazari on Flickr under a Creative Commons License.