Transfer of bisphenol A from thermal printer paper to the skin.
Level 5 - mechanism / opinion, no new human data
Laboratory analytical and experimental skin transfer study
PubMed 20623271 · doi:10.1007/s00216-010-3936-9
What was done
Researchers analyzed 13 thermal printing paper samples for bisphenol A (BPA) content and measured the transfer of BPA to forefingers and middle fingers after 5 seconds of contact under dry, wet, and greasy skin conditions. They assessed whether repeated touches altered transfer amounts and evaluated skin extractability using ethanol over 60 to 120 minutes to assess skin penetration. Potential daily occupational exposure for cashiers working 10 hours per day was modeled.
What was found
BPA was present in 11 of 13 thermal papers at concentrations of 8–17 g/kg. Holding receipt paper for 5 seconds transferred roughly 1 µg BPA (range 0.2–6 µg) to dry finger pads and approximately ten times more to wet or greasy fingers. Transferred amounts to dry skin did not increase significantly across 10 touch sites or decrease after touching BPA-free paper. BPA transferred from receipt paper remained largely extractable after 2 hours, whereas BPA in ethanol solution became unextractable within 60–90 minutes. Theoretical exposure for touching receipts 10 hours/day was estimated at up to 71 µg/day (42 times below the tolerable daily intake).
Why it matters
This study provides direct measurement showing that handling thermal receipts transfers BPA onto human skin, with skin moisture or grease markedly increasing the transferred amount. It shows that skin contact is a measurable exposure pathway, although estimated average daily contact levels remained below standard regulatory thresholds.
Limits
The abstract does not disclose the number of human participants tested. Systemic absorption, internal dose, and metabolic clearance were not directly measured, relying on surface ethanol extractability and theoretical exposure calculations.
Cited by
- supports Touching thermal paper receipts, particularly when wearing hand cream, causes significant absorption of bisphenols into the body.