Aug. 12, 2011 -- Paper money may contain trace levels of bisphenol A (BPA), a chemical found in some plastics and other consumer products, a study shows.
But only small amounts of BPA are absorbed through our skin when we handle the money, the study shows.
The study is published in Environmental Science & Technology.
BPA is considered an endocrine disruptor, which means it looks or acts like a hormone in the body. It may be associated with behavioral and reproductive issues. Young children may be particularly vulnerable to these effects. As a result, many manufacturers have taken steps to eliminate the BPA in baby bottles and some sippy cups.
The study analyzed BPA levels in 156 forms of paper money from 21 countries. All of them contained some BPA.
The highest amounts of BPA were found in paper money from Brazil, the Czech Republic, and Australia. The lowest amounts of BPA were seen in paper money from the Philippines and Thailand. Levels of BPA in U.S. dollars were about average.
"Although there were high levels found in paper money, there were not high levels absorbed through the skin," says researcher Kurunthachalam Kannan, PhD, a scientist at the Wadsworth Center and professor of environmental health and toxicology at State University of New York, both in Albany.
BPA levels in cash were higher than what is found in house dust. But human intake of BPA from currency is at least 10 times less than what is seen with house dust.
The study only looked at skin absorption of BPA from currency, but there may be other routes of exposure. Some people -- including children -- may put their money in their mouths, he says. "Dermal [skin] exposure is low because what is absorbed through the skin is only a fraction of what is on the paper."
"Limit handling of paper money, and when you do touch it, rinse your hands with water," he says. "I wouldn't put money in my mouth, and don't let children handle money either."
How BPA Gets on Money
So how does BPA get onto our money in the first place? It may rub off from thermal paper receipts that are often placed next to paper money in wallets. These receipts are coated with BPA to prevent smudging.
Cashiers may absorb higher levels of BPA than other people because of their constant contact with both cash and receipts. "Further studies are needed to assess exposure among cashiers and others who come into frequent contact with paper currencies," Kannan says.
Cashiers should consider protective gloves while handling receipts and currency, he says. Now Kannan and colleagues are analyzing levels of BPA in other household paper products such as newspaper and toilet paper.
Andy Igrejas, national campaign director of Safer Chemicals, Healthy Families in Washington, D.C., says the new findings confirm and broaden previous research about levels of BPA found in the money supply.
"There is only so far that we can go in protecting ourselves from these chemicals because exposures are so ubiquitous and involve things that are hard to avoid, like money," he says. "The answer has to come from looking at the big picture of aggregate BPA exposure."
Robin M. Whyatt, DrPH, a professor of clinical environmental health sciences and the deputy director of the Columbia Center for Children's Environmental Health in New York City, says any health risks associated with BPA in money may be highest for cashier and bank tellers.
"Cashiers and bank tellers who handle money on an eight-hour a day basis may have a reasonable amount of absorption," she says.
There are a lot of unanswered questions about BPA exposure and the risks associated with such exposure, she says. "There is a lot of controversy about the potential health effects of the health risks of BPA and studies are under way."
Perspective of Chemical Industry
Steven G. Hentges, PhD, of the Polycarbonate/BPA Global Group of the American Chemistry Council, a trade group in Arlington, Va., says paper currency is expected to carry traces of many substances and microorganisms.
"Finding trace levels of BPA in currency is neither surprising nor a concern," he tells WebMD via email. "Human exposure to BPA from contact with paper currency is minor and orders of magnitude below science-based safe intake levels set by regulatory authorities worldwide."
"Furthermore, available data suggests that BPA is not readily absorbed through the skin," he says.