Bisphenol A exposure via thermal paper receipts.

Bisphenol A (BPA) has one of the highest production volumes of all chemicals worldwide. It has been widely studied because of its endocrine modulating activity. In addition to dietary intake, absorption of BPA via the skin from handling thermal papers is believed to be a relevant route of exposure. We studied BPA exposure via thermal paper receipts in simulation experiments performed by three volunteers, and examined urinary excretion of BPA. We also evaluated background BPA excretion among the Finnish working-age population. The geometric mean BPA excretion among non-occupationally exposed working-age Finns (n=121) was 2.6 μg/l, the range being 0.8-18.9 μg/l. The 95th percentile of the non-occupationally exposed people was 8 μg/l, and this was set as the reference limit for the non-occupationally exposed population. In the first simulation experiment, which was conducted under conditions representing the most likely exposure, i.e., the work of a cashier in a supermarket, BPA excretion remained below the reference limit in all participants. In the second simulation experiment, with more intensive, short-time handling of thermal paper (three times 5 min), urinary excretion also remained at or below background levels (highest value being 10.3 μg/l). The calculated maximum BPA excretion per day after handling thermal paper was less than 0.2 μg/kg of body weight, suggesting a total daily intake over 25 times lower than the European Food Safety Authority's (EFSA's) proposal for a temporary tolerable daily intake (temporary TDI) (5 μg/kg/day).