Posted by Crystal on May 31, 2001 at 18:28:37:
Yes, there is a link between permanent hair color and bladder cancer. When pregnant, it is recommended to use semi-permanent hair color over permanent. The chemicals are different, much less harsh.
This is one of the largest and most comprehensive studies ever conducted on the issue. Investigators analyzed 897 cases of bladder cancer where information about hair dye use was available, and compared these patients with a similar number of adults who did not use permanent hair dye.
The investigators found that women who used permanent hair dye at least once a month were twice as likely as women who did not use permanent hair dye to develop bladder cancer. They took cigarette smoking--a known risk factor for bladder cancer--into consideration in their calculations.
Those who reported regular use of the hair dye for at least 15 years were more than three times as likely to develop bladder cancer as non-dye users.
All of the shades use essentially the same chemicals, but there's quite a lot more of the chemicals in dark brown and black than there are in blonde.
International Journal of Cancer February 2001
Also, USC did a study and found the same results. See the link I provided!
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