Dear EarthTalk: Are commercial hair dyes dangerous to my health?
—Alice Martin, Ithaca, NY
It’s a relative rarity, but people do develop allergic reactions to commercial hair colorings. The most common allergens in dye are ammonia and peroxide, or the chemicals p-Phenylenediamine (PPD) or diaminobenzene. All permanent dyes use PPD to adhere to the hair shaft and peroxide to open it. A person can become allergic to these chemicals even after years of use, and the chemically sensitive sometimes find them too toxic to use at all.
In addition to allergies, hair dye has come under scrutiny in recent years due to a possible link to various types of cancer. In 1994, the Journal of the National Cancer Institute announced that deep-colored dyes (like dark brown and black), when used over a prolonged period of time, seemed to increase the risk of non-Hodgkin’s lymphoma and multiple myeloma. In 200l, the International Journal of Cancer found that those who use permanent hair dye are 2.1 times more likely to develop bladder cancer (as are their hairdressers).
For a truly natural hair dye option, consider a non-chemical treatment like Ecocolors, or try henna, which is made from the powdered leaves of a desert shrub called Lawsonia. Henna has been used for thousands of years to color hair and skin (Cleopatra was a famed proponent). Although it seems to pose no health risks, some sensitive people might still experience allergies when using it.