Elevated levels also were seen in women who smoked cigarettes or breathed secondhand smoke and women exposed to phthalates, chemicals that are found in vinyl products. BPA is used in some cigarette filters and phthalate-containing food packaging.
One strong point of the study is that the scientists tested the women’s blood or urine for compounds, known as biomarkers, left behind by tobacco smoke and phthalates. Those produce more reliable results than the canned food data, which were based on questionnaires.
Information was not collected about the women’s use of plastics, packaged foods, dental treatments or bottled water, all of which may contain BPA.
“There is still very little known about the relative contribution of various sources of BPA to measured urinary BPA concentrations,” the authors wrote. The senior investigator was Bruce Lanphear, formerly of Cincinnati Children’s Hospital Medical Center and now at Simon Fraser University in British Columbia.
For U.S. children, about 99 percent of their BPA comes from food, but no comparable studies have been conducted for adults, Braun said. Additional research is needed, he said, to identify and quantify other sources so that pregnant women can find ways to reduce their fetuses’ exposure.
“If we’re not doing anything about that [fetal exposure], we’re really not doing much to prevent exposure to the most susceptible population,” Braun said.
Woodruff, who did not participate in the study, called upon regulators to control the use of BPA in common items like cash register receipts and aluminum cans. She said the chemical is so ubiquitous it is like air pollution – impossible for people to avoid.
“You can’t avoid it unless you get rid of it,” she said. “Much of this is a failure of the current laws to adequately address non-voluntary chemicals which could harm our health.”
BPA by Occupation
Median BPA in urine (ppm)
|Health Care Worker||2.1|
|Sales or service worker||2.1|
Source: “Variability and Predictors of Urinary Bisphenol A Concentrations During Pregnancy,” Environmental Health Perspectives, Oct. 8, 2010
This article originally ran at Environmental Health News, a news source published by Environmental Health Sciences, a nonprofit media company.