The European Commission has banned 22 chemicals used in hair dyes, following research by its scientific committee that links long-term use of certain products to an increased risk of bladder cancer. The ban, which comes into force on December 1, 2006, is part of the commission's strategy to establish a list of hair dye chemicals that are safe. Right now 115 files from manufacturers are under evaluation. The commission plans to ban all permanent and non-permanent hair dyes for which either no safety files have been submitted or have received a negative opinion.