SAN FRANCISCO (KPIX 5) -- The store clerk hands them to you all the time, but paper receipts pose a potential health hazard.
Receipts come in handy if you want to return something, but now an environmental watchdog group is warning that those slips of paper could pose a health risk.
It's a common question for holiday shoppers: would you like a paper or an emailed receipt?
Well, now an environmental watchdog group is urging customers to opt for e-receipts and limit their contact with the paper variety.
"Most cash register receipts are coated with a toxic chemical," said Caroline Cox of the Center for Environmental Health.
Cox was part of a team that tested more than 100 receipts from California stores.
They found a handful of receipts, including those issued by high-end retailers Neiman Marcus and Nordstrom, contained Bisphenol A, or BPA, a chemical known to cause reproductive toxicity.
"It has kind of an extraordinary ability to mess with our hormones," Cox said.
And equally concerning, Cox says, 90 percent of the other receipts tested contained a concerning replacement – a chemical called Bisphenol S, or BPS.
"It's a chemical cousin of BPA and is probably not so well studied, but equally toxic," Cox said.
Both chemicals are found in what are known as thermal receipts. The BPA and BPS develop the dyes used in printing.
The chemical industry insists BPA is safe and says that overall, consumer exposure to BPA is extremely low.
Nordstrom and Neiman Marcus did not comment, but most of the other retailers found with BPA in their receipts, say they are looking at alternatives.
"If you don't need the receipt, just say no thank you..." Cox recommends.
Cox says these chemicals are also found in gas pump and ATM receipts, as well as boarding passes.
The biggest concern: pregnant women and cashiers.
She says e-receipts are the way to go.
Sam Delson, with the California Environmental Protection Agency's Office of Environmental Health Hazard Assessment said he doesn't take issue with CEH's recommendations.
He told KPIX 5 that people should "minimize contact with thermal receipts."
Delson said, "People should exercise good hygiene and minimize contact."
But what about gift receipts and other necessities during the holiday season and beyond?
Cox says to consider folding them in half, handling receipts from the back and then washing your hands.
The chemical BPA has long been used in plastics and the linings of canned foods. Now many companies are phasing it out, substituting it with BPS, which Cox described as equally toxic.
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