Every time you handle a store receipt made with thermal paper containing BPA you rub a little bit of estrogen-mimicking powder onto your fingers that allows an opportunity for the endocrine-disrupting chemical to be absorbed into your body.
The Environmental Working Group (EWG) writes, "Thermal paper is widely used for point-of-sale receipts, prescription labels, airline tickets and lottery tickets. Thermal printers use paper that is coated with a dye and developer (BPA or an alternative chemical). Heat from the thermal printing head triggers a reaction between the dye and developer, allowing the black print to appear."
STRAIGHT FROM EWG.ORG WEBSITE:
In animal tests, scientists have produced evidence that BPA can induce abnormal reproductive system development, diminished intellectual capacity and behavioral abnormalities and can set the stage for other serious conditions, such as reproductive system cancer, obesity, diabetes, early puberty, resistance to chemotherapy, asthma and cardiovascular system disorders. It has caused epigenetic changes, meaning alterations in the way genes switch off and on and genetic changes that can be passed on to the next generations.
Frequent exposures to relatively large amounts of BPA in receipts are an obvious concern to every shopper, but even more so to the legions of people who staff cash registers and bag groceries at tens of thousands of retailers across the country. These workers handle BPA-loaded receipts hundreds of times a day, with as yet unknown consequences for their health (Biedermann et al 2010). According to the U.S. Department of Labor’s Bureau of Labor Statistics, as of May 2009, the two largest U.S. occupations were “retail salespersons” and “cashiers,” with more than 7 million Americans in those jobs.
Retail workers carry an average of 30 percent more BPA in their bodies than other adults, It is unclear how much BPA-coated receipts contribute to people's total exposure to the ubiquitous plastics chemical. What is certain, however, is that since many retail outlets already use BPA-free paper for their receipts, this is one source of contamination that could easily be eliminated completely.