Characterization of patients with occupational allergy to two new epoxy hardener compounds

BACKGROUND: The practical importance of two recently described epoxy hardener allergens—1,3‐benzenedimethanamine, N‐(2‐phenylethyl) derivatives (1,3‐BDMA‐D) and hydrogenated formaldehyde benzenamine polymer (FBAP)—as occupational allergens remains to be defined. OBJECTIVES: To describe patients diagnosed at the Finnish Institute of Occupational Health (FIOH) with positive reactions to 1,3‐BDMA‐D or FBAP. METHODS: We searched FIOH's patch‐test files from January 2017 to December 2020 for patients examined due to suspected occupational contact allergy to epoxy compounds. We analyzed the patch‐test results and sources of exposure to various epoxy hardeners and focused on occupations, symptoms, and the sources of exposure to 1,3‐BDMA‐D and FBAP. RESULTS: During the study period, 102 patients were examined at FIOH for suspected occupational contact allergy to epoxy compounds. Of these, 19 (19%) were diagnosed with contact allergy to 1,3‐BDMA‐D (n = 10) or FBAP (n = 12). The largest occupational group was sewage pipe reliners (n = 8). Seven different hardener products contained FBAP, whereas 1,3‐BDMA‐D was present in only one hardener used by spray painters. CONCLUSIONS: A substantial number of patients with suspected occupational epoxy resin system allergy tested positive to in‐house test substances of 1,3‐BDMA‐D and/or FBAP.