Contact allergy to epoxy hardeners

Area of Science:

• Dermatology
• Occupational Health
• Toxicology

Background:

• Diglycidylether of bisphenol A resin is a primary sensitizer in epoxy systems.
• A subset of patients develop allergies to epoxy hardeners.
• The Finnish Institute of Occupational Health utilizes specialized epoxy compound patch testing.

Purpose of the Study:

• To determine the prevalence and clinical significance of allergic reactions to various epoxy hardeners.
• To identify key sensitizing agents within epoxy hardener formulations.

Main Methods:

• Screening of patient test files from January 1991 to March 2013 for contact allergy to epoxy hardeners.
• Analysis of clinical records for occupation, co-existing allergies, and exposure details in patients with allergic reactions.

Main Results:

• M-xylylenediamine (n=24), 2,4,6-tris-(dimethylaminomethyl)phenol (tris-DMP; n=14), isophorone-diamine (n=12), and diethylenetriamine (n=9) were the most frequent positive epoxy hardeners.
• Other hardeners like trimethylhexamethylenediamine and tetraethylenepentamine also caused reactions, though often without clear exposure.
• Reactions to hexamethylenetetramine, dimethylaminopropylamine, and ethylenediamine dihydrochloride were not linked to epoxy products.

Conclusions:

• 2,4,6-tris-(dimethylaminomethyl)phenol (tris-DMP) is a significant sensitizer in epoxy hardeners.
• Tris-DMP should be incorporated into standard patch test series for epoxy chemicals.
• Understanding specific hardener allergies is crucial for managing occupational contact dermatitis.