A chemical compound used in many permanent hair dyes has been named Allergen of the Year for 2025 by the American Contact Dermatitis Society (ACDS). Toluene-2,5-diamine sulfate (PTDS) is an ...

Metallic hair colors are the ... This way, your hair stays healthy and is primed for coloring. When you apply the dye, wear gloves and work from the roots to the tips, making certain of even ...