For the most part, the answer is a qualified yes -- at least as far as cancer is concerned. Dozens of studies have ruled out connections between hair dye and bladder and breast cancer, brain tumors, and non-Hodgkin's lymphoma.
Health experts still stop short of giving dyes a clean bill of health, though, partly because of the skin reactions they can cause. Kathleen Davis, M.D., an integrative dermatologist in New York City, says that contact dermatitis from p-Phenylenediamine (PPD), a known allergen, can result in temporarily swollen eyelids or rashes around the hairline. Since PPD is more concentrated in darker shades, it's a particular concern for brunettes.
Would-be blondes have bleach to blame for blisters and burning on sensitive scalps as well as lightheadedness. But the bleaching processes have improved: "The amount of ammonia in dyes and bleaches is very slight now compared with 20 years ago," says Eva Scrivo, a New York City colorist, referring to the potentially skin-irritating chemical used in products to help color penetrate hair. "In the '60s, products contained 20 percent ammonia, but now they're down to 1.5 percent." She says some new bleaches don't contain any ammonia at all -- and still work well if you have light to medium brown hair. If you're worried, try a patch test before subjecting your whole scalp to the dye in question, or take a lighter approach. "With highlights," Scrivo says, "nothing touches the scalp."
"Natural" or Not?
If you're bothered by even the chance that dyes could irritate your skin, you might turn to "natural" brands. While no studies yet make the claim that the dyes you find at the health-food store are any safer than those at the drugstore, "it's just intuitive," says Davis. "The fewer harsh chemicals you're using, the better off your body is."
But "natural" doesn't always mean safe. Read the labels. The only truly natural, plant-derived, permanent hair color is henna -- and not even every shade of it. John Masters, of the eponymous salon and beauty brand, says, "The lone shade that's 100 percent natural is that orange-red one, which doesn't suit many people." Henna is also famously unpredictable in its saturation, so it's no surprise that he -- like most professional colorists -- prefers not to use it.
For the naturally inclined, vegetable dyes are the next best thing. Most still contain nonvegetable content, so you (or your colorist) should scan the ingredients. What you likely won't find in these picks are resorcinol, which helps adjust tone but can harm skin, and ammonia. The more natural dyes also tend to have low levels of PPD and avoid formula-preserving parabens that may pose adverse hormonal effects. If you're a do-it-yourself type, look for dyes like Changes by Tints of Nature and Naturtint at health-food stores. Scrivo also recommends the Herbatint line -- both salon and drugstore versions. "I found it more mild on my own hair," she says, "and it has really good gray coverage, which can be hard to get with vegetable-based colors.
While even most vegetable dyes still can't be described as all-natural, they are inching closer. Like the other experts we spoke with, Masters sticks with herbal colors that contain no parabens, ammonia, or resorcinol. He sometimes uses the Elumen Hair Color line, which uses an entirely new process to put color on strands of hair. Instead of damaging hair by disrupting the strand's cuticle -- as happens with ammonia or peroxide, and which leads to dried out and damaged 'dos -- the color molecules penetrate the shaft through magnetic attraction. Hair remains healthy, and fewer chemicals end up on your head -- or swirling down the drain.
For many, that potential environmental impact is the best incentive for using less toxic options. "You wouldn't believe how many toxic chemicals are being rinsed from colorists' sinks into the waterways," Masters says, noting that some later show up in freshwater fish and groundwater supplies. So even as the health risks of using hair dye have been shown to be fewer and less serious than once believed, you might explore gentler versions for environmental reasons. Luckily, with an exploding natural-brands beauty market, that's not hard to do.
Text by Abbie Kozolchyk