Study Links Some Hair Dyes to Kind of Cancer: NY Times Article
Posted by Carrie on January 27, 2004 at 11:29:47:
Hello everyone -I usually post on the Henna Page mehndi forum, but they asked me to
post this over here as well.
-Carrie
Study Links Some Hair Dyes to Kind of Cancer
By MARY DUENWALD
Published: January 24, 2004
cientists have found more evidence for a possible link between non-
Hodgkin's lymphoma and long-term use of dark hair dye. A study of
more than 1,300 women in Connecticut shows that those who began
coloring their hair before 1980 increased their chance of developing
the disease by 40 percent.
And among those who used permanent rather than nonpermanent dyes, who
chose dark colors — browns, reds and black — and who dyed their hair
frequently (eight times a year or more) for at least 25 years, the
risk doubled, said Dr. Tongzhang Zheng, a Yale epidemiologist who led
the study. The results are published in the current issue of the
American Journal of Epidemiology.
"For those who used light colors, there was no such increase in
risk," Dr. Zheng noted.
Nor was there significantly increased risk among women who used
nonpermanent dyes. The difference between permanent and nonpermanent
dyes is that permanent ones are mixed with an oxidizing agent. In
that process, new chemicals are created, some of which may be
carcinogenic, Dr. Zheng said.
Non-Hodgkin's lymphoma is a form of cancer that begins in the body's
lymph system. The average American woman has a 1-in-57 chance of
developing the disease in her lifetime, according to the American
Cancer Society. For a man, the chance is 1 in 48.
Suspicions that hair dyes might increase cancer risk have been around
since the 1970's, said Dr. Eugenia Calle, the cancer society's
director of analytic epidemiology, but studies over the years have
found no connection between the dyes and most forms of cancer.
The Yale researchers and the National Cancer Institute are now
looking into whether there are any genetic influences that might make
certain women more likely to develop lymphoma after exposure to dye.
Because all the studies done so far, including the latest one, have
been observational rather than clinical, their findings do not
provide evidence that hair dye causes lymphoma, said Gerald McEwen,
vice president for science at the Cosmetic, Toiletry and Fragrance
Association, a trade group in Washington.
"There's no smoking gun here," Mr. McEwen said, "no causal
relationship."
In this study, the researchers found no increase in cancer risk among
women who started dying their hair after 1980, no matter how
frequently they did so or what color they used. In the late 1970's,
hair dye makers stopped using certain coal-tar ingredients that had
been found to cause cancer when fed to laboratory rats and mice.
"This is the first study that's been able to look at the time period
after 1980," said Dr. Shelia Hoar Zahm, deputy director of cancer
epidemiology and genetics at the National Cancer Institute, who
collaborated on the study. "It suggests that the later formulations
are safer. If the risk is limited to those people who started use
before 1980, it means we're really in better shape now."
Another possibility, however, is that women have not had time to use
the new products long enough for them to have any adverse effect, Dr.
Zheng said. "It's very hard for us to say that now the products are
safe," he said.
Previous studies on the association between hair dye and non-
Hodgkin's lymphoma have been mixed. A few have shown no association,
but two, one done in 1988 and one in 1992, have suggested that there
may be a link.
If hair dye does play some role in lymphoma, Dr. Calle said, it would
make sense that the darker colors, which have greater concentrations
of ingredients, would have the strongest effect.
Follow Ups
- Thanks much! n/t
Catherine Cartwright-Jones 12:26:01 1/27/2004
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