BPA, the controversial chemical used to line cans, may raise a child's risk for developing heart problems or kidney disease by the time they are adults, new research suggests.
Bisphenol A is used in food packaging to prevent corrosion, but an also be found in plastic bottles, tableware and food storage containers. The chemical seeps from these sources into foods where it enters the body and is eventually excreted through urine. However, people exposed to lots of BPA through their diets have higher levels of the chemical lingering in the body.
BPA has been linked to hormone-disrupting effects, including reproductive and neurological problems that young children may be more prone to experiencing. Previous studies suggest 92 percent of U.S. children have some trace of BPA in their urine, according to the study's authors.
"Food represents the single largest source [of BPA] for kids and adolescents," study author Dr. Leonardo Trasande, an associated professor in pediatrics, environmental medicine and health policy at NYU Langone Medical Center in New York, told CBSNews.com. "Studies have identified that bisphenol A may contribute to heart disease in adults."
To find out if kids carry this risk, Trasande and his team reviewed data from 710 children and adolescents between ages 6 to 19 who were part of a long-running government study, the National Health and Nutrition Examination Survey. The researchers were looking for measurements on the children's BPA levels in their urine, as well as the presence of a protein called "albumin."
Albumin is not typically leaked into urine, however studies suggest that the presence of the protein may be a marker for damage associated with kidney disease in adults. Trasande also said the protein may be indicative of what's called "oxidative stress," an imbalance of compounds in the body that can damage cells and is thought to contribute to the formation of some diseases, including heart disease.
The researchers divided children into four groups based on the amount of BPA in their urine samples (from lowest to highest), and found that children exposed to the highest levels of BPA had more albumin in their urine compared to kids with the lowest BPA levels. Those findings remained true when comparing the high BPA group to the general population, and even even when ruling out other potential factors that can influence health, such as high blood pressure, insulin resistance (a precursor to diabetes), exposure to tobacco smoking, socioeconomic status and a child's weight.
The new study was published online Jan. 9 in Nature's Kidney International.
While the presence of albumin suggests these kids may face later disease risks, Trasande is quick to point out the study did not prove cause and effect, and more research is needed to look at how BPA effects blood pressure and other measures of heart and kidney function.
"Does this mean that children exposed to BPA are at a higher risk for heart and kidney disease? We can't say for sure right now," he said. However, he adds that the study "adds further concern to the decision of the FDA to not ban BPA from food uses."
BPA is banned in the European Union and Canada. The U.S. Food and Drug Administration (FDA) banned BPA for the manufacturing of baby bottles and sippy cups in July 2012, however many companies had already begun to phase out the chemical from those products given to children.
As Trasande alluded to, the agency rejected a petition in March of 2012 to ban BPA entirely, saying at the time many of the studies that found links to health risks from BPA exposure were conducted in animals and may not be translatable to humans. BPA is still used in cans and other packaging although some companies have said they plan to look into alternatives to eventually phase it out.
Another study of Trasande's, published in JAMA in September, found links between a child's BPA exposure to obesity risk, finding 22 percent of children exposed to the highest levels of BPA were obese, compared to only 10 percent of kids exposed to the lowest levels (Watch Trasande explain those findings on the left).
He points out that the analysis for his latest study ruled out body mass index (BMI), a measure of obesity, so the studies' conclusions are independent from one another. However, he said they add to the growing body of concerns for BPA's effects on children.
A website sponsored by the American Chemistry Council that in the past has disputed these types of studies says BPA is one of the most thoroughly tested chemicals used today and the weight of scientific evidence supports its use.