Contact dermatitis from hydrazine derivatives

A 36-year-old man who worked at a chemical factory manifested contact dermatitis due to hydrazine derivatives. Thirty workers out of 130 in this factory were suspected of contracting contact dermatitis on exposed areas. Aminoguanidine hydrochloride, a blender for chicken feed, and the precursor and intermediate products of 3-amino-1,2,4-triazole, a herbicide, were found to be allergens for this contact dermatitis.