Although often suspected by many clients as being the cause for localized body rashes, we hardly ever come across anyone with a confirmed allergy to commercial pigment dyes in clothing. One is more likely to develop contact dermatitis from dyes and rubber found in leather footwear, paraphenylene diamine (PPD) in hair dye and latex elastic in underwear. Detergent residues left in clothing can also irritate eczema-prone skin, causing it to flare up, and animal fibers such as wool, silk, mohair and fur in clothing can cause allergies. Cotton is the least allergenic clothing fiber. Most non toxic commercial clothing dyes are quite harmless, but occasionally reactions can be attributed to a particular type of dispersal dye (Disperse Blue 106 and 124) and formaldehyde residues found in new clothing, however these are usually removed after a few washes. Sweating and tight fitting clothing increases the likelihood of a reaction in dermatitis prone people.
Reference: Clothing Dye Allergy
