Hair Color Problems European regulators banned 22 hair dye chemicals in 2006 as part of a safety investigation because of a study linking dyes to bladder cancer. One of those ingredients is p-phenylenediamine (PPD), found in many permanent hair colors. Mary Janssen, author of Naturally Healthy Hair, says PPD is the cause of many allergic reactions to hair dye and that it has been linked to cancer.  Women who used permanent hair dyes regularly (at least once a month) for 15 years or more were found to be three times as likely to develop bladder cancer as women who didn't dye their hair. Even back in 1991 a study found that hairstylists had triple the risk of developing breast cancer when they worked with hair dyes for five years or more.   People who used dark hair dye for two decades or more had a four times greater risk of dying from two cancers of the immune system, non-Hodgkin's lymphoma and multiple myeloma (bone marrow). A study published in the January 2004 issue of the American Journal of Epidemiology also found a link between long-term use of dark hair dyes and non-Hodgkin's lymphoma. According to the study dark hair dye increased their chance of developing the form of cancer by 40 percent. The risk reportedly doubled among women who used permanent hair dye. Dr. Hampton (of Aubrey's) believes that hair is alive but that the use of bad chemicals will actually kill hair. He also says that people can go bald from using chemicals even when there is no family pattern of hereditary baldness. Dr. Hampton states that it is important for all consumers to read product labels and avoid buying products that contain chemicals, because many times cosmetic and hair care companies will camouflage the truth of what they use in their products. Another problem with analyzing hair coloring products is the confusing array of strangely named ingredients. Plus even industry experts comment regarding ending up with something other than the shade that is shown on the box, "Don't think the color on the box is the color you'll get," says Freier, a cosmetology instructor. "There are so many variables, like what chemicals are already in your hair and what your natural color is, that go into how your hair will turn out." The stronger hair chemical lobby has prevailed many times in overriding the outcries of the smaller, more conservative natural ingredient manufacturers. Several decades ago, the chemical hair dye group knew that the main ingredient in the coal-tar hair dyes manufactured at the time, prompted an allergic reaction in some individuals. Fearing the FDA would ban the sale of hair dyes because some users develop a rash or have other allergic reactions, the industry successfully lobbied Congress to pass an act to make coal-tar hair dyes exempt from the adulteration provision. Most hair dyes in use today have ingredients from petroleum sources, but have been considered exempt coal-tar dyes by FDA because they contain some of the same compounds found in those older dyes. As long as manufacturers include a label warning that the product could cause skin irritation, they can slide by. The good news is that although dark colored strong permanent hair colors may be dangerous to one's health, non-permanent vegetable based dyes and natural henna have not been found to be carcinogenic. The FDA issued a monograph that approved henna for this use. (It should be noted that while investigating the tatooing industry some black henna was found to be tainted with PPD.) Plus, most of the time henna is a more economical way to color hair, being substantially less expensive than many of the chemical treatments. Henna applications also tend to last longer and thus a new kit is purchased less often.