Is there a role for the PPD skin test when a hair colour is based on other dyes?
The Association of Registered Trichologists ask world renowned Toxicologist and expert on hair dye safety, Dr David Basketter, whether published scientific literature supports the role of a PPD skin test when colourants is based on other dyes. The answer is an emphatic “yes”. In this special scientific article, Dr Basketter explains why.
