BPA Health Concerns continued...
“Many researchers have reported exposure to bisphenol A from the diet,” Teeguarden tells WebMD. “The real question is and always has been, ‘Do we get enough of the bioactive form of the chemical in the blood to cause adverse effects?’”
Blood and urine samples from 20 adult volunteers were collected hourly during the day and several times at night over 24 hours. Over the course of the study day, the participants ate three meals made from canned foods with linings that contained BPA.
As a result, the average consumption of BPA was estimated to be 21% higher than the average for 95% of adults in the United States.
Despite the high exposure, levels of bioactive BPA in the blood were undetectable in the samples, Teeguarden says.
Independent analysis of the samples by the CDC and the FDA’s National Center for Toxicological Research confirmed the findings.
In the CDC analysis, bioactive BPA was below the limit of detection in all 320 analyzed blood samples.
Impact of BPA on Children Unknown
The CDC’s Calafat says the finding that blood levels of bioactive BPA are much lower than urine levels is not a big surprise.
“Based on the properties of BPA we would expect to see this,” she says.
The study appears in the September issue of the Journal of Toxicological Sciences.
In a news release, the industry trade group North American Metal Packaging Alliance called the research a “landmark study” providing “definitive evidence that adverse health effects from bisphenol A are highly unlikely.”
Sonya Lunder, who is a senior analyst with the research and advocacy organization Environmental Working Group, says although the findings are somewhat reassuring for adults, the study did not address the safety of BPA exposure in developing fetuses, babies, and children.
“Ninety-five percent of Americans have measurable BPA in their urine on any given day,” she tells WebMD. “A longstanding concern has been that children, infants, and developing fetuses may have no ability or very limited ability to metabolize this chemical the way adults do.”
Calafat says a host of studies funded by a $14 million grant from the American Recovery and Reinvestment Act should shed new light on the safety or harms of BPA exposure in adults and children within the next year or so.