FRIDAY, Sept. 22, 2006 (HealthDay News) -- Is your deodorant boosting your breast cancer risk? And how much chemical preservative in hand and body lotions is too much?
News reports over the past few years have heightened consumer awareness of the myriad chemicals found in everyday beauty and hygiene products, but two expert dermatologists say it pays to investigate before tossing any product into the bathroom wastebasket.
The debate over deodorants and antiperspirants is one good example. Small studies have suggested that daily use of these products might raise a woman's risk for breast cancer over time, especially given the armpit's proximity to sensitive breast tissue.
But Dr. Lisa Donofrio, an assistant clinical professor of dermatology at Yale University School of Medicine, said that "there have also been a couple of studies that have been pretty good at showing that [these products] -- at least the aluminum in them -- are not really related to breast cancer." While future studies might turn up additional data, "this debate right now is probably closer to 'case closed,' " she said.
One issue that remains an ongoing source of concern for Donofrio is that of preservatives called "parabins" found in a wide range of beauty products meant to have a very long shelf life. One reason manufacturers tend to use parabins is that a small minority of consumers develop allergies to a competing class of preservatives, formaldehyde releasers.
"So, parabins are now found across the board in beauty items -- makeup, and most commonly in lotions," Donofrio said. But the problem with parabins is that they "are estrogenic, meaning they will bind to estrogen receptors [on cells], and in test tube studies, they actually stimulate breast cancer cells," she said. Higher levels of circulating estrogens has long been a prime risk factor for breast cancer.
Industry experts note that parabins are used in extremely small amounts in health and beauty products. "For that reason, they say they're just in too small amounts to cause any problems," Donofrio said. "But over a lifetime, with daily use of these creams, we don't actually know what the cumulative dose really is."
For that reason, Donofrio advises that anyone not allergic to formaldehyde releasers shy away from products containing parabins, which are usually noted on label ingredient lists as either methyl parabin or propyl parabin. For those people who are allergic to formaldehyde releasers, she suggests using products containing a third class of preservative, sodium benzoate. Compared to parabins, "it's the lesser of two evils," the Yale expert said.
Another long-debated issue -- the connection between hair dyes and certain malignancies -- may have already been solved by industry, said Dr. Steven Feldman, a professor of dermatology at Wake Forest University School of Medicine. "First of all, the link has been talked about, but the studies don't really support it," he said. In any case, he said, hair dyes used today no longer contain the suspected carcinogen that gave rise to these fears in the first place.
Of course, consumers can develop lesser ailments, such as rashes and other signs of allergy, from skin and hair products. While manufacturers can help minimize the risk, Feldman said there's not much they can do to ensure that no one ever develops a reaction to their product.
"A person can be allergic to practically anything," he said. "Fragrances, especially, are one of the more common allergens -- people can expose themselves to them even through their fabric softener in the laundry."
As with any allergy, individuals who notice a reaction should note what they were using at the time and consult their doctor, if necessary. Feldman did offer one piece of advice: "Stick to well-recognized brands," he said. "I know some people fear big business, but companies that have a lot at stake don't want to blow it, and with business, the more they have to lose, the safer I think the product will be."
On the other hand, he said, "if you go for some fly-by-night company that promises you some herbal remedy, then, if somebody sues them, they just close up shop." Buying from a nationally recognized brand may "give you some assurance about quality that you might not otherwise get," Feldman said.
Many consumers may not be aware that health and beauty products are not subject to the tough federal safety standards that guide drug development.
"Most of us expect that the products we find on store shelves have been tested for safety, but the [U.S.] government has no authority to require tests," Jane Houlihan, vice president for science at the Washington, D.C.-based nonprofit Environmental Working Group, said in a prepared statement. "An average adult is exposed to over 100 unique chemicals in personal care products every day -- these exposures add up."
Not everyone agrees that consumers need to worry about the products they apply to their bodies each day, however. In a prepared statement, scientists at the American Council on Science and Health -- which describes itself as a consumer-based advocacy group that receives some "no strings attached" funding from the cosmetics industry -- said organizations like the EWG "have invested a great deal of work in publicizing supposed health risks from myriad chemicals that have long been in everyday use with no evidence of harm to humans."
According to the New York City-based ACSH, much of the evidence for these "scares" relies on high-dose animal tests that "are not good predictors of human cancer risk."
Yale's Donofrio said that argument does have some merit. However, she said she's more concerned about the absorption of toxins through the skin and their slow build-up in the body over time.
"If you start thinking in terms of 'Well, this does this to cells in the test tube, and I'm using X amount of this over this amount of years,' then there's the potential that I could end up being those [affected] cells," she said.
Find out more about the science of beauty products at the U.S. Food and Drug Administration.