Bisphenol A (BPA) is a chemical used for manufacturing items such as polycarbonate plastics for water bottles and resin liners for food cans. However, it can leach out of products, is considered an endocrine-disrupting chemical, and has been linked to a range of health problems.
Although diet appears to be the main source of human exposure, researchers are examining various routes including dermal absorption.
BPA has been used as a color developer on thermal receipt paper, including cash register receipts and tickets. Researchers have reported that BPA can transfer from receipts to paper money during handling. Now, they report that recycling of thermal receipt papers is a source of BPA contamination of paper napkins, toilet paper, food packaging, and other paper products, writes Michael Woods, Assistant Director for Science Communications in the American Chemical Society’s Office of Public Affairs.
Whereas thermal receipt papers contained the highest concentrations of BPA (milligram-per-gram), some paper products, including napkins and toilet paper, made from recycled papers contained microgram-per-gram concentrations of BPA.
To conduct their study, the researchers analyzed hundreds of samples of thermal cash-register receipts and 14 other types of paper products including magazines, tickets, mailing envelopes, newspapers, food contact papers, food cartons, airplane boarding passes, luggage tags, printing papers, business cards, napkins, paper towels, and toilet paper, collected from several cities in the U.S. as well as Japan, Korea, and Vietnam.
Kannan and Liao found that BPA concentrations in thermal receipt papers from the U.S. were lower than in samples from Korea and Vietnam. Papers from Japan did not contain BPA. Tickets, flyers, and other paper products contained BPA, but the researchers estimated that 98% of human exposure to BPA from paper comes from thermal receipts.
The researchers provided context for their results:
The daily intake of BPA (calculated from median concentrations) through dermal absorption from handling of papers was 17.5 and 1300 ng/day for the general population and occupationally exposed individuals, respectively; these values are minor compared with exposure through diet.
Source: “Recycling thermal cash register receipts contaminates paper products with BPA,” ACS PressPac, 11/30/11
Source: “Widespread Occurrence of Bisphenol A in Paper and Paper Products: Implications for Human Exposure,” Environmental Science & Technology, 9/23/11
Image by bollin (Torsten Werner), used under its Creative Commons license.
Rachel Petkewich is a freelance science writer and editor. She has worked as a research scientist in the chemical industry and spent eight years as a staff writer and editor at various science journals and magazines, including Chemical & Engineering News.