Hair dye allergy testing not valid and could lead to sensitisation

Hair dyes contain chemicals such as p-phenylenediamine (PPD), an extremely potent skin sensitiser and often used as a main ingredient, European allergy experts said.

“Some of the hair dye products that are for sale advise consumers who develop skin reactions... to consult their physician,” they wrote.

“Physicians should be aware that the test is insufficiently validated and that it cannot work as a screening tool for the prevention of hair dye reactions.”

Melbourne dermatologist Associate Professor