Identification of the allergenic sensitizing potential of bisphenol A substitutes used in the industry.

Background: Bisphenol (BP-)A is a chemical used in Europe to produce polycarbonate plastics and epoxy resin or as colour developer in thermal paper. Due to its toxicity, BPA presence was restricted by European regulations. Therefore, substitute chemicals are replacing BPA.

Objective: To assess the allergenic sensitizing potential of 27 substitutes to BPA used in the industry.

Methods: The expression of two costimulatory molecules and six cytokines were analysed by flow cytometry in mouse bone marrow-derived dendritic cells (BMDCs) exposed to the chemicals.

Results: All substances except one induced overexpression of at least one receptor and were thus identified as having allergenic sensitizing potential. Based on the BMDC model, they were classified as extreme (1 out of 27), strong (20 out of 27) and moderate (5 out of 27) sensitizers. BPA was classified as a moderate sensitizer and BPF was the only substitute classified as a non-sensitizer. The more potent substitutes induced more than 2-fold secretion of CCL3, CCL4 and/or CCL5 by dendritic cells.

Conclusion: Most of the BPA substitutes tested in this study have an allergenic sensitizing potential; 24 of them being more potent than BPA itself. Only BPE, BPF and 2,4-BPS appeared to be weaker sensitizers than BPA.