New research studies conducted by a toxicologist at a Department of Energy Pacific Northwest National Laboratory under a grant from the U.S. Environmental Protection Agency and presented at the American Association for the Advancement of Science (AAAS) conference show that “human exposure is likely to be too low for estrogenic effects” from typical daily exposure to BPA.
This comprehensive investigation systematically analyzed 150 studies of 30,000 people in 19 countries, including infants and children, to see if concentrations of BPA in the blood were high enough to result in “estrogenic” activity, as some scientists have claimed. When BPA is taken in orally, it is rapidly converted to a substance with no known biological activity as it is absorbed into the body, leaving very little BPA to enter the bloodstream.
The results show that most people are exposed to much lower levels of BPA than are often used in so-called low-dose studies conducted in animal models. According to Justin Teeguarden, a senior research scientist who conducted the analysis, “BPA in the blood of the general population is many times lower than blood levels that consistently cause toxicity in animals.”
“The results showed that human blood levels of BPA are expected to be too far below levels required … to cause biological effects,” according the government lab’s announcement. “Looking at all the studies together reveals a remarkably consistent picture of human exposure to BPA with implications for how the risk of human exposure is interpreted,” said Teeguarden. Based on the study’s results, the levels of BPA humans are exposed to are so low, “people’s exposure may be many times too low for BPA to effectively mimic estrogen in the human body,” the lab announcement stated.
And The Independent reported that other scientists at the meeting disputed other claims that somehow BPA could cause obesity. “My hypothesis is that a modern Western diet determines the level of BPA exposure – the more of it you eat, the more BPA you’re exposed to – with the result that over-eating causes obesity etc., but also causes higher BPA exposure,” said Professor Richard Sharpe of the Medical Research Council’s Centre for Reproductive Health in Edinburgh.
“If this interpretation is correct, it means that a Western, poor diet is responsible on the one hand for causing the disorders and on the other hand for causing increased exposure to bisphenol A, [which is] innocently associated with the disorders as a result,” he said.
BPA has been used to make polycarbonate plastic and epoxy resins linings for more than 50 years and is among the most tested chemicals in commerce, having been the subject of over 5,000 studies. Health and regulatory authorities around the world—including the U.S. Food and Drug Administration (FDA), European Food Safety Authority (EFSA), Japanese National Institute of Advanced Industrial Science and Technology and the World Health Organization—have repeatedly reviewed the data and reaffirmed the safety of BPA. This study further builds on that body of evidence.
BPA is the building block of many products that help improve our lives and enhance our safety. Polycarbonate plastic made with BPA is used in shatter-resistant products such as protective eye wear, bike helmets and shin guards. BPA-based epoxy resins are used in food can linings to help minimize the risk of botulism from canned food and have many important industrial applications. Learn more facts about BPA.
This latest study, combined with the vast body of BPA science, should dispel old myths and provide new science-based evidence about the safe use of BPA.