Bisphenols A and S in thermal paper - occupational exposure ?

Objective: Bisphenol A (BPA) has been used for more than 50 years now in producing polycarbonate plastics, and epoxy resins, and also as a developer in thermal paper including cash register receipts, credit card receipts, and self-adhesive labels. However, replacing BPA with bisphenol S or BPS is tending to become general practice in this field. Experimental data would suggest that BPA could represent a risk for human health because of its endocrine disruptor type effects that might occur at very low doses. However, there is very little toxicological data available on BPS. Nevertheless, the studies that have been conducted have found toxicological profiles that are close between the two bisphenols. The objective of this research was to assess occupational exposure to BPA and to BPS by biomonitoring during handling of thermal papers, by determining the levels of uptake by assaying the two compounds in the urines of exposed workers and in the urines of workers not exposed occupationally.
Method: Urine sampling campaigns were conducted in 13 companies from 2013 to 2014. Of those companies, 12 have retail activities, requiring handling of cash register receipts and of credit card receipts. The exposed workers on those sites were referred to using the generic term "cashiers". The 13th company was an industrial printing firm producing, in particular, access tickets. A total of 211 volunteers were monitored, including 137 exposed employees and 74 other employees who were controls. The urine samples were accompanied by a questionnaire designed to give information on the occupational activities, diets, and extra-occupational activities.
Findings: In the population of "cashiers", the total BPA excretions of the exposed group were significantly higher than those of the control group. The results from the printing company confirm the effect of handling thermal paper on the total BPA excretions but also on the free BPA excretions. This data indisputably shows that handling thermal paper caused an increase in urinary excretion of BPA in the monitored subjects.
As regards BPS, a statistically significant increase in the urinary excretion of BPS in the "cashiers" who handled thermal paper containing that bisphenol on a daily basis was also observed in comparison with the controls.