Meet the 2025 Allergen of the Year: Toluene-2,5-diamine Sulfate (PTDS)
And the 2025 Allergen of the Year is…toluene-2,5-diamine sulfate (PTDS). Each year, the American Contact Dermatitis Society (ACDS) names an Allergen of the Year to raise awareness about common allergens. Toluene-2,5-diamine sulfate (PTDS), also known as toluene diamine sulfate or 2,5-diaminotoluene sulfate, is an aromatic amine that can be used as a hair dye alternative […]