You're going to be surprised where the controversial chemical bisphenol A-which has been linked to significant health problems-is showing up now.

According to a release today by the Environmental Working Group (EWG), laboratory tests that it commissioned found the endocrine-disrupting BPA on 40% of register receipts sampled from major U.S. businesses and services, including outlets of McDonald's, CVS, KFC, Whole Foods, WalMart, Safeway and the U.S. Postal Service. Receipts from Target, Starbucks, Bank of America ATMs and other enterprises were BPA-free or contained only trace amounts.

The total amounts of BPA on receipts tested were 250 to 1,000 times greater than other, more widely discussed sources of BPA exposure, including canned foods, baby bottles and infant formula, it says. EWG collected receipts from various locations in seven states and the District of Columbia and had them tested by the University of Missouri Division of Biological Sciences laboratory.

BPA is used in many consumer products, but most famously in the epoxy lining of cans and in polycarbonate plastic for food- and beverage-contact purposes. The chemical mimics estrogen in the body; the Journal of Human Reproduction last year published a report that said male workers with high exposure to BPA were several times more likely to experience sexual dysfunction. In addition, the Journal of the American Medical Association published the first-ever study of the chemical conducted on humans in September 2008 confirming previous reports linking BPA to the potential for causing heart disease, diabetes and unusually high levels of particular liver enzymes. 

For more information on EWG's report, click here.