According to the National Cancer Institute, “A case-control study in Italy found no association between use of permanent hair dye overall and risk of leukemia, although users of black permanent dyes, but not of other color dyes, did have an increased risk. This study, however, did not collect information on the timing or frequency of hair dye use.”

Another cancer concern revolves around hair stylists and bladder cancer. This is because exposure to chemicals found in hair dye may put hair stylists at a higher risk of developing bladder cancer.

“Over the years, some epidemiologic (population) studies have found an increased risk of bladder cancer in hairdressers and barbers,” according to the National Cancer Institute. One such study, published in 2008, found that chemicals that hair stylists were exposed to may be carcinogenic in general.

Other research also demonstrates concerning conclusions when it comes to hair stylists and cancer risk,  especially when it comes to aromatic amines.

“Researchers from the Division of Occupational and Environmental Medicine in Lund, Sweden, wanted to measure long-term exposure to known and suspected carcinogenic aromatic amines among hairdressers,” according to Medical News Today. “To do this, they assessed blood samples from 295 female hairdressers, 32 regular users of hair dyes and 60 people who had not used hair dyes in the past year. The researchers also gathered data on the participants' other jobs, hobbies and lifestyle that could have influenced the results.”

“Overall, levels of aromatic amines did not differ significantly between the three groups. However, in the hairdressers, their weekly levels of aromatic amines called o- and m-toluidines were shown to correspond with the number of permanent light hair color treatments they applied to clients. Toluidines are known to be carcinogenic,” according to Medical News Today.

At the end of the day, the risk you’re willing to take to dye your hair is up to you. With conflicting studies showing different results, it’s a matter of deciding what you’re personally comfortable with.

To find out more about carcinogens found in hair dye, you can consult the National Toxicology Program. The National Toxicology Program (NTP) publishes ingredients found in hair dyes. Information about this publication can be found through the American Cancer Society.