Sunday, August 17, 2008

Chuck the Nalgenes?

So there's been a lot of fuss lately about bisphenol A (BPA) in polycarbonate bottles. Just to add to the confusion, the FDA deemed that an adequate margin of safety existed for exposure to BPA from food contact uses. Here's the executive summary from the draft assessment released on the 14th:
This document describes the Food and Drug Administration’s (FDA) safety assessment of Bisphenol A (BPA) as it relates to exposure through use in food contact materials. This assessment is particularly focused on the concerns for developmental toxicity identified in recent assessments of BPA, including those of the National Toxicology Program and their expert panel. BPA is an impurity in FDA-regulated food additives, including epoxy-based food can liners and polycarbonate baby bottles. FDA estimates that BPA exposure from use in food contact materials in infants and adults is 2.42 μg/kg bw/day and 0.185 μg/kg bw/day, respectively. FDA has determined the appropriate no observed adverse effect level (NOAEL) for its assessment of BPA to be the NOAEL for systemic toxicity of 5 mg/kg bw/day (5000 μg/kg bw/day) derived from two multigenerational rodent studies. This NOAEL results in adequate margins of safety of approximately 2,000 and 27,000 for infants and adults, respectively. The data reviewed on highlighted endpoints, such as the prostate gland and developmental neural and behavioral toxicity, were insufficient to provide a basis to alter the NOAEL used to calculate the margins of safety. FDA has concluded that an adequate margin of safety exists for BPA at current levels of exposure from food contact uses. At a later date, FDA will publish a separate document that provides a safety assessment of BPA exposure from other FDA-regulated products.
More interesting information from the National Toxicology Program's (NTP) draft report on BPA (a major scientific review underlying the FDA report) can be found here.

2 comments:

kenny g said...

So, I'm not going to grow boobies by drinking from my Nalgene?

brian said...

I think the layer of mold on the inside of your bottle prevents any BPA from leaching out anyways, so you got nuthin to worry bout.