Researchers have developed a more accurate method of measuring bispehnol A (BPA) levels in humans and found that exposure to the endocrine-disrupting chemical is far higher than previously assumed.
The study, published in the journal the Lancet Diabetes & Endocrinology on Dec. 5, provides the first evidence that the measurements relied upon by regulatory agencies, including the U.S. Food and Drug Administration, are flawed, underestimating exposure levels by as much as 44 times.
“This study raises serious concerns about whether we’ve been careful enough about the safety of this chemical,” said Patricia Hunt, Washington State University professor and corresponding author on the paper. “What it comes down to is that the conclusions federal agencies have come to about how to regulate BPA may have been based on inaccurate measurements.”
BPA can be found in a wide range of plastics, including food and drink containers, and animal studies have shown that it can interfere with the body’s hormones. In particular, fetal exposure to BPA has been linked to problems with growth, metabolism, behavior, fertility and even greater cancer risk.
Despite this experimental evidence, the FDA has evaluated data from studies measuring BPA in human urine and determined that human exposure to the chemical is at very low, and therefore, safe levels. This paper challenges that assumption and raises questions about other chemicals, including BPA replacements, that are also assessed using indirect methods.
Hunt’s colleague, Roy Gerona, assistant professor at University of California, San Francisco, developed a direct way of measuring BPA that more accurately accounts for BPA metabolites, the compounds that are created as the chemical passes through the human body.
Previously, most studies had to rely on an indirect process to measure BPA metabolites, using an enzyme solution made from a snail to transform the metabolites back into whole BPA, which could then be measured.