Investigators proposed limitations to epoxy chemicals in workplace environments, as a substantial number of patients reacted to the epoxy hardener compounds featured in the study.
A new investigation from Finland found that a substantial number of patients with suspected occupational epoxy resin system allergy had tested positive to 1.3-benzenedimethanamine, N-(2-phenylethyl) derivatives (1,3-BDMA-D) and formaldehyde benzenamine polymer (FBAP), which are 2 in-house epoxy hardener compounds.
Investigators noted that epoxy resin based on diglycidyl ether of bisphenol A has been linked to the development of concomitant or solitary contact allergy to epoxy hardeners.
However, allergic contact dermatitis (ACD) caused by epoxy products can not always be diagnosed on patch testing with commercial test substances, which had led investigators to patch test a selection of epoxy compounds as in-house test substances.
As such, investigators led by Sari Suomela, MD, PhD, of the Finnish Institute of Occupational Health (FIOH), studied patients being examined for ACD caused by epoxy products by patch testing with established epoxy allergens in addition to FBAP, 1,3-BDMA-D, 2-methylpentane-1, and 5-diamine.
Suomela and investigators examined patients at the FIOH clinic of occupational dermatology for a suspected occupational skin disease.
Patch testing was performed using Finn Chambers in accordance with the ESCD guidelines, and tests were read 2 to 3 times depending on the day of the week on which the tests were applied.
Patients were asked to contact the clinic if they noticed any new reactions after the final reading.
From there, the team examined occupational and non-occupational exposure to positive allergens on the basis of product information including safety data sheets and labelling in manufacturer inquiries when needed.
Patch test and patient filles from 2017-2020 were examined in search of any positive reactions to the epoxy hardener compounds featured in the patch test series. Investigators then 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.
A total of 102 patients were examined at FIOH for suspected occupational contact allergy to epoxy compounds.
Among these patients, 19 had reaction to the epoxy compunds featured in the study.
A total of 12 patients had positive reactions to FBAP, 8 of which had used products that contained FBAP. A majority of these reactions were linked to sewage pipe re-liners.
Additionally, 50% of these patients had a concomitant sensitization to DGEBA-R, and 7 patients had a concomitant positive reaction to diaminodiphenylmethane (MDA).
A total of 10 patients reacted to 1,3-BDMA-D, but only 2 of them were clearly exposed to 1,3-BDMA-D.
These 2 patients, who were both spray painters, also reacted to their own paint hardener that contained 1,3-BDMA-D.
Among these patients, 7 of them (70%) also reacted to m-xylylenediamine (MXDA), and 5 had also used MXDA-containing products.
A majority of patients developed eczema as a result of these products in the hands, face, and upper extremities.
“This suggests that skin protection fails very easily, and that extreme care should be taken to avoid contamination of the skin and workplace surfaces with epoxy chemicals,” the team wrote. “Importantly, over half of the patients had to change their trade because of severe work-related skin symptoms reoccurring on the face in particular.”
The study, "Characterization of patients with occupational allergy to two new epoxy hardener compounds," was published online in Contact Dermatitis.