New worries about safety of hair dyes

An expert committee of the European Commission has raised doubts about the safety of permanent hair dyes after claims the colourings could cause cancer.

The Scientific Committee on Cosmetic and Non-food Products has criticised the hair-dye industry for failing to produce evidence to enable it to assess its products.

After an investigation into the safety of two chemicals used in permanent hair dyes, the committee concluded: "The information submitted is insufficient to allow an adequate risk-assessment to be carried out."

The investigation concerned the chemicals para-phenylenediamine and tetrahydro-6-nitroquinoxaline.

Permanent hair dyes have been linked with a range of conditions, including bladder cancer, arthritis and damage to unborn children. Britons spend £175 million ($566 million) a year on such products.

Researchers at the University of Southern California, who last year studied 1500 people with bladder cancer, found women who had used permanent hair dyes at least once a month were at two to three times greater risk of developing the cancer.

Hairdressers with more than 10 years in the business had a five-fold increased risk. However, the study found no link between cancer and semi-permanent and temporary hair dyes.

The cancer-causing components of hair dyes are aromatic amines that are known to break down DNA and have been shown to cause cancer in animals. They are easily absorbed through the skin.

Bladder cancer is diagnosed in more than 13,600 Britons a year, nearly 4000 of them women. It kills 4850, just over a third of them women.

Hair dyes can also produce strong allergic reactions in some people. In May 2000, a 39-year-old woman in Birmingham suffered an anaphylactic shock and died after colouring her hair. She had complained of feeling hot and breathless.

Those at highest risk are women who use a dark dye on grey roots every four to six weeks.

The committee sought details of all permanent dyes, including unpublished data on any possible cancer-causing properties. It was not satisfied with the material it received.

Dr Ian White, head of the committee and a consultant dermatologist at St Thomas' Hospital, London, was quoted as saying: "They have not provided ample information that the dye is safe. Isn't it amazing that a product should have such wide gaps in its toxicological requirements but be on sale?"

He added that consumers should not worry unduly as permanent hair dyes containing the suspect chemicals had been on sale for 40 years. Only women using the products over many years could be at risk.

A spokeswoman for the Cosmetic Toiletry and Perfumery Association said twice as many men as women contracted bladder cancer - not what might be expected if hair dye were a cause.

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