(NaturalNews) Chemist John Warner learned about thermal- and pressure-sensitive papers while working for Polaroid years ago. A powdery coating that contains BPA, a dye and a solvent is laid onto one side of the paper. Then heat or pressure is applied causing the substances to merge, and the ink's color is released. Remembering his work with thermal paper at Polaroid, Warner wondered if BPA coating was still used on thermal paper. He assigned his university students to collect shopping receipts in the Boston area and to test them for BPA. And they found it.
The federal government warned that 93 percent of Americans have BPA contamination. Parents were warned to protect their children from exposure. But no mention was made of cash machine or retail receipts.
Warner and his colleagues at the Warner Babcock Institute for Green Chemistry in Wilmington, Mass., published data based on the substantial amounts of BPA on 10 receipts collected in the Boston area. Not all store receipts use ink that contains BPA. The safe receipts look the same as the unsafe ones.
BPA, or bisphenol A, an estrogen-mimicking pollutant, has been tied to many potential health risks. It has been associated with plastics, in particular, baby bottles. It is believed to cause behavior problems in children, as well as obesity and heart ailments. Among adults it has been linked to breast cancer, diabetes, and other health problems. It affects reproductive patterns, causes early puberty and diminishes intellectual capacity. It causes diseases among animals.
Another researcher found that the BPA would rub off onto fingers. Dry fingers collected plenty of BPA, but wet ones collected ten times as much. And the longer the paper was held, the greater the BPA transfer.
The University of Missouri analyzed 36 receipts gathered from automated teller machines and popular fast food, grocery and drug retailers. The amount of BPA was 250 to 1,000 times that commonly found on food cans or plastic bottles. In fact, the amount of BPA found on one popular fast food receipt was equal to that found in 126 cans of a popular grocery store item.
BPA on sales receipts can enter the body in two ways. It can leach through skin or be ingested when someone touches their fingers to their mouths or to food.
People who handle receipts frequently are believed to be more at risk. A cashier who used hand cream (which would enhance the permeability of the chemical) might sustain exposures approaching 50 micrograms per kilogram of body weight. People working in retail have 30 percent more BPA than other Americans.
Bisphenol sulfonate is a possible safe substitute for the bisphenol A for receipts. Until widespread use of a safe ink is instituted, people should avoid holding receipts or touching them. Retailers who do not use bisphenol A ink may begin to advertise the safety of their receipts by adding the line "BPA-free" to their cash receipts.
The US Environmental Protection Agency has begun to evaluate the safety of BPA and alternatives but it is uncertain how long this will take or what will happen after.