BPA exposures, effects deserve more careful look.

Posted by Evan Beach at Jul 28, 2010 01:00 PM |

(Emily Barrett contributed to this review.)

A story in the Daily Mail alerts readers to a very likely exposure route for bisphenol A (BPA) – cash register receipt paper. The chemical is often found on the paper, where it (Correction, 7/29/10: mixes with a dye to form color) helps prevent the dye from fading delete.

The Daily Mail should be commended for drawing attention to the receipt paper issue as most media attention has focused on other applications of BPA – usually its presence as a component in food can linings and polycarbonate water bottles. But, the article ignores the more serious risks of BPA exposure to developing fetuses and provides almost no information on the scope of the problem.

The article refers to the BPA on receipt papers as a "startling discovery." In fact, BPA has been used in thermal printing for decades. Likewise, the tendency of BPA to behave like a female hormone was first reported more than 50 years ago. The reporter does not indicate what exactly was discovered by the researchers or who those researchers are. 

The story would have been much more informative if it explained key differences in the way BPA is used in paper as opposed to its applications in plastics. In thermal printing, BPA usually coats an entire piece of paper, and it is present as the free, unbound molecule. A typical receipt could contain as much as 100 milligrams. In food can linings or polycarbonate water bottles, BPA is locked up in the structure of the plastics. Exposure does not occur unless the plastics break down, for example from the effects of heat or sunlight, or if BPA was left over as a contaminant from the manufacturing process. Thus, the "free" BPA content in a typical food can would be thousands of times lower than that found on a receipt made from thermal paper.

If, in fact, the unbound BPA that coats receipts gets into the body, it may contribute to serious health problems.  Contrary to what the Daily Mail story suggests, there is no clear-cut evidence that male impotence is among them.  Several recent studies have looked at exposure to BPA in relation to various aspects of male reproduction, but the results have been inconsistent. Only one study actually found impaired sexual function in men in relation to BPA exposure, and that was in men exposed to extraordinary levels during their work at BPA-producing factories. Thus, the Daily Mail article’s claim that shopping could make men impotent is a stretch, given current research.

This misleading conclusion distracts from the more serious health concern surrounding the chemical, namely, how BPA exposure during pregnancy can affect the development of the fetus. A substantial body of research from humans and animal models now implicates prenatal BPA exposure in a wide range of long-term health concerns, ranging from diabetes to aggressive behavior in children. If anyone should be avoiding cash register receipts, it’s expectant mothers, not adult men.

The Daily News story also doesn't discuss any solutions to the exposure problem except for a tongue-in-cheek suggestion that men avoid shopping. It would have been useful to explain that BPA is not the only chemical that can be used to stabilize dyes in thermal paper. In fact, it is not even the best performing chemical in this application.  BPA-free receipt paper is available at somewhat higher cost, and it is the norm in Japan. Daily News readers would surely appreciate knowing that they could pressure retailers to adopt safer alternatives.