If you thought that the health risks associated with hair-smoothing keratin treatments were behind us, think again. Though the formulas used in salons today typically are less dangerous than the notorious Brazilian Blowout, a product whose risks came to light back in 2010, the current formulas are far from safe. Yet many woman are still ignorant of—or ignoring—the dangers. And even if you wouldn’t dream of using such a product yourself, you could still be at risk while someone else at your salon is getting her hair done. Here’s the straight talk…

Keratin is a protein that exists naturally in hair. The idea of a keratin salon treatment is to make hair smoother, sleeker, straighter and easier to style. For the treatment, a stylist applies a mixture of keratin and formaldehyde (a strong preservative) to the hair, which fills in the gaps in each hair shaft…then the stylist “seals” the mixture into the hair, lock by lock, using a very hot flat iron. At this high temperature, the liquid formaldehyde converts to gas vapors.

Yes, formaldehyde gas—swirling in a hot cloud all around your head. It sounds outrageous, like it ought to be illegal, doesn’t it?

Whether inhaled or absorbed through the skin, formaldehyde is linked to a host of health problems. “Formaldehyde can cause irritation of the skin, eyes, nose and lungs, as well as dizziness or lightheadedness. Even short-term exposure can cause asthma-like symptoms, while long-term exposure can cause permanent central nervous system damage and ongoing pulmonary problems. So far, the risk for cancer from long-term exposure is controversial, but there is good data to support a link between formaldehyde and the development of leukemia,” said Amy McMichael, MD, a professor of dermatology at Wake Forest Baptist Medical Center.

Despite these risks, women who want to keep their hair sleek and straight tend to repeat the treatment every eight to 12 weeks or so, increasing their exposure.

The danger was first brought to public attention a few years ago when the FDA warned the Brazilian Blowout hair products company—the most well-known manufacturer, though far from the only one—to change its formulation and its product labels, which the agency described as “adulterated” and “misleading,” respectively. A public back-and-forth followed, with the company first insisting that the government’s lab tests were flawed and that the products were safe, then ultimately agreeing to change its products and labeling.


As the battle heated up and public awareness grew, salons began offering “no-formaldehyde” and “low-formaldehyde” treatments. But these are still problematic—and here’s why…


  • Many of the supposedly formaldehyde-free hair-smoothing products contain ingredients that turn into formaldehyde when they break down during the heat application portion of the salon treatment! Ingredients that are synonyms for or that break down into formaldehyde include formalin, formic aldehyde, methanal, methylene glycol, methylene oxide, oxomethane and oxymethylene.



  • Other products that claim to be formaldehyde-free were found, when tested by the US Occupational Safety and Health Administration (OSHA), to contain significant levels of formaldehyde.



  • The truly formaldehyde-free products don’t do much to smooth out the hair shafts, leaving many consumers dissatisfied.



  • The low-formaldehyde products, while not as toxic as the original formulations, still carry health risks.



  • Some salons still use high-formaldehyde products.



In all honesty, it’s not easy to avoid formaldehyde today. It’s used in a vast array of products, from plywood to carpeting to household cleaners. Clothing and most other textiles (towels, sheets, curtains) often are treated with formaldehyde to keep them looking fresh during shipping and warehousing. Formaldehyde also is used as an ingredient in many cosmetics, including soaps, lotions, even mascara and eye liner.

OSHA requires that employers take protective precautions for workers who are exposed to formaldehyde at concentrations of 0.1% or higher. Scary comparison: According to the FDA, the original Brazilian Blowout products contained nearly 12% formaldehyde.

But just because your salon uses a product called something other than Brazilian Blowout doesn’t make it safe. Other products that expose you to formaldehyde during treatment include Acai Professional Smoothing Solution, Acai Therapy, Advanced Brazilian Keratin Treatment, Brasil Cacau, Cadiveu, Chocolate Extreme De-Frizzing Treatment, Copomon/Coppola, Express Blow Out, Keratin Complex Smoothing Therapy, Marcia Teixeira Advanced Brazilian Keratin Treatment, Marcia Teixeira Extreme De-Frizzing Treatment, Natural Keratin Smoothing Treatment, Professional Brazilian Blowout Solution, Soft Chocolate Gentle Smoothing Treatment and Soft Gentle Smoothing Treatment.

Bottom line: At this point, there is no effective salon-performed, keratin-based hair-smoothing product that can be considered completely safe, according to Dr. McMichael. If you have been receiving keratin treatments, it’s time to give serious consideration to stopping. Even if you have not noticed any negative effects as yet, it doesn’t mean that you’re immune—cumulative exposure only increases your risk.

If you patronize a salon that offers keratin treatments: Ask to be booked for a time when the salon can guarantee that no such treatment will be taking place…or at least insist on having your hair styled in a separate room to limit your exposure to the fumes.