Cash register receipts and paper money have been found to contain high levels of bisphenol A (BPA), a chemical linked to cancer, obesity and early puberty, a study published Wednesday says.
Researchers from US non-profit groups Safer Chemicals, Safer Families and the Washington Toxics Coalition tested till receipts made from thermal paper which they collected from 22 popular retailers and cafes, and found that half of them were coated with large quantities of BPA.
"Since BPA in thermal paper is present in a powdery film, we suspected it could easily travel from those receipts to other objects," says the study, led by Washington Toxics Coalition scientist Erika Schreder.
Holding the receipts for just 10 seconds caused up to 2.5 micrograms of BPA to transfer from the paper onto a person's fingers, and rubbing the receipts increased around 15-fold the amount of BPA transferred from the receipts onto fingers, the study said.
From the fingers, the BPA transferred easily onto dollar bills: the researchers found the chemical on 21 of 22 bills tested, although in much lower levels than on the till receipts.
BPA from thermal paper receipts passes through the skin
More than 130 studies over the past decade have linked even low levels of BPA to serious health problems, including breast cancer, obesity and early onset of puberty.
The European Union last month followed Canada's lead and banned the use of BPA in baby bottles after tests showed the petroleum product can affect neural development and behavior in laboratory animals exposed to the chemical in the womb or very early in life.
But BPA is still widely used in plastic water jugs, soft drink cans, hockey helmets, mobile phone housings, computers, car bumpers and other consumer products, and the health impact of the chemical on humans has been disputed.
Last month, the World Health Organization said BPA does not accumulate in the body, but admitted that "recent experimental and epidemiological studies found associations between low BPA exposure levels and some adverse health outcomes."
Andy Igrejas, director of Safer Chemicals, Healthy Families called on US lawmakers to toughen up the law that regulates chemicals in the United States in the light of the study's findings.
"BPA on receipts, dollar bills and in many other products is a direct result of the absurdly lax controls on chemicals in the United States," he said, calling on the incoming Congress to reform "the failed 1976 Toxic Substances Control Act."
The Rayburn Cafe in the US House of Representatives was one of the establishments where till receipts were found to have high levels of BPA, according to the study, which was published online by the two nonprofits.
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