Brazilian hair straightening is a semi-permanent hair straightening method done by temporarily sealing a liquid solution consisting of formaldehyde or a formaldehyde derivative and a preservative solution into the hair with a hair iron.
The technique has many variations and is known by several other names and brands, including Brazilian Blowout, Breezilian straightening, Brazilian Keratin Treatment, Professional Probelle, BKT, and Keratin Cure. It is called Escova Progressiva in Brazil and Alisado brasileiro in Portugal.
The original formulation included formaldehyde or methylene glycol . The two products readily interconvert, and coexist in chemical equilibrium, when dissolved in water or body fluids. Since formaldehyde is a known health hazard, the compositions have been banned in several countries including Canada and the European Union. It is still performed in the United States, though there are regulations and have been controversies regarding the treatment. As of 2024, the states of Maryland and California have begun the process to ban all personal care products containing formaldehyde. In California, Governor Gavin Newsom signed it into law under the Toxic-Free Cosmetics Act.
Characteristics Brazilian hair straightening treatments are meant to mostly or partially eliminate hair frizz and straighten curls and waves. They can be performed on all types of hair, whether natural or chemically-treated (bleached, highlighted, colored, permed, relaxed or previously straightened).
The effect usually lasts about three months. Treatment must be repeated every few months to straighten the new hair growth.
Although keratin treatment is not long-lasting, hair should not be treated with keratin more than three times per year. Excessive keratin can damage hair, causing it to break off. Process The application technique is similar to the Japanese Yuko System, in that the hair is heated with flat irons to bind the product into the hair cuticle.
Depending on the treatment used, the customer may have to avoid washing, wetting, pinning or constraining the hair in any way (e.g. with hair clips, pony tails, or headbands) for some period after application, up to three days.
It is also confused or mistaken for keratina, another hair treatment.
The name "straightener" is arguably incorrect because it does not chemically alter the structure of the hair.
Formaldehyde controversy
Between 2010 and 2012, there was a dispute between the manufacturers and importers of Brazilian hair straightening products on one hand, and various US federal and state health agencies on the other, about the proper labeling and health warning of the products. The dispute centered about the chemical compounds formaldehyde () and methylene glycol (), which are the active ingredients of the process, responsible for binding the keratin to the hair. Formaldehyde is a gas that, when dissolved in water (including fluids in the human body), converts partially to methylene glycol. In the liquid, the two compounds coexist in a chemical equilibrium.
Regulations about formaldehyde levels
Formaldehyde in the air has long been recognized as a major occupational hazard in many industries; such as those using urea-formaldehyde (UF) adhesives, or UF-based products like fiberboard, and UFFI spray foam insulation. Levels below 0.05 parts per million (ppm) were found to be positively correlated with eye and nasal irritation. It has also been implicated in the development of childhood asthma, and, in 2006, the WHO International Agency for Research on Cancer (IARC) classified it as a 'known human carcinogen'.WHO IARC (2006): IARC Monographs on the Evaluation of Carcinogenic Risks to Humans Volume 88 (2006): Formaldehyde, 2-Butoxyethanol and 1-tert-Butoxypropan-2-ol". Published by WHO Press
Because of these concerns, since 1976 or earlier, European regulations on cosmetics banned products containing or releasing formaldehyde. Products containing any aldehydes more than 0.001% in leave-on products or 0.01% in rinse-off products were required to list the ingredients explicitly in their product labels.
The US Federal Occupational Safety and Health Administration (OSHA) sets a long-term permissible exposure limit (PEL) of 0.75 ppm of formaldehyde in the air, and a short term exposure limit of 2.0 ppm.
Occupational safety and health hazard alert OSHA issued a hazard alert and created an informational site in response to an investigation into complaints from stylists and hair salon owners about exposure to formaldehyde while using hair smoothing products such as Brazilian Blowout (Acai Professional Smoothing Solution, Professional Brazilian Blowout Solution), Brasil Cacau Cadiveu, Keratin Complex Smoothing Therapy (Natural Keratin Smoothing Treatment, Express Blow Out, Natural Keratin Smoothing Treatment Blonde), and Marcia Teixeira (Advanced Brazilian Keratin Treatment, Extreme De-Frizzing Treatment). OSHA conducted air sampling at multiple salons and found formaldehyde in the air when stylists were using hair smoothing products. Some of these products were labeled "formaldehyde free" or did not list formaldehyde on the product label or in the Material Safety Data Sheet (MSDS). In most cases, where the label did not state that the product had formaldehyde in it, OSHA found that hair salon owners using those products did not know that hair smoothing products contain or could expose workers to formaldehyde because manufacturers, importers, and distributors did not include the correct hazard warnings on the product's label or MSDS.
During Federal OSHA investigations, air tests showed formaldehyde at levels above OSHA's limits in salons using Brazilian Blowout Acai Professional Smoothing Solution, labeled "formaldehyde free", and Brasil Cacau Cadiveu. Both Federal and State OSHA have found violations at several manufacturers, importers, and distributors (GIB LLC dba Brazilian Blowout, Keratronics Inc., Pro Skin Solutions, M&M International Inc., Copomon, INOVA Professional). The violations include failing to list formaldehyde as a hazardous ingredient on the MSDS (the hazard warning sheet) provided to downstream users (e.g., salon owners, stylists), failing to include proper hazard warnings on product labels, and failing to list the health effects of formaldehyde exposure on the MSDS. Labels must include ingredient and hazard warning information and the MSDS must provide users with information about the chemicals in a product, the hazards to workers, and how to use a product safely.
If salon owners decide to use products that may contain or release formaldehyde, they must then follow the requirements in OSHA's formaldehyde and hazard communication standards to protect worker safety. Requirements include steps such as testing salon air during treatments to determine formaldehyde levels, providing adequate ventilation and appropriate personal protective equipment for workers performing treatments, and training workers on the hazards of formaldehyde. Failure to follow the requirements of the formaldehyde and hazard communication standards has consequences. As part of OSHA's enforcement duties, the agency issues citations to five manufacturers, three distributors, two beauty schools and 42 salon owners. Citations were issued for reasons including, but not limited to: failing to communicate the hazards of exposure to formaldehyde, formaldehyde levels were above the OSHA 15-minute short-term exposure level, and not following the requirements of OSHA's formaldehyde standard.
California safety and health investigation
California Attorney General Kamala Harris announced a settlement with GIB LLC dba Brazilian Blowout requiring a payment of $600,000 in fines and changes to Brazilian Blowout Acai Smoothing Solution and the Brazilian Blowout Professional Smoothing Solution MSDS and labeling. Under the terms of the settlement, GIB is required to:
Produce a complete and accurate safety information sheet on the two products that includes a Proposition 65 cancer warning; distribute this information to recent product purchasers who may still have product on hand; and distribute it with all future product shipments. The revised safety information sheet will be posted on the company's web site. Affix "CAUTION" stickers to the bottles of the two products to inform stylists of the emission of formaldehyde gas and the need for precautionary measures, including adequate ventilation. Cease deceptive advertising of the products as formaldehyde-free and safe; engage in substantial corrective advertising, including honest communications to sales staff regarding product risks; and change numerous aspects of Brazilian Blowout's web site content. Retest the two products for total smog-forming chemicals (volatile organic compounds) at two Department of Justice-approved laboratories, and work with DOJ and the Air Resources Board to ensure that those products comply with state air quality regulations. Report the presence of formaldehyde in its products to the Safe Cosmetics Program at the Department of Public Health. Disclose refund policies to consumers before the products are purchased. Require proof of professional licensing before selling "salon use only" products to stylists.
Health concerns The U.S. Food and Drug Administration (FDA) warns that Brazilian Blowouts are hazardous to the health of those who use them and the hairdressers who apply them.
Concerns over the presence of formaldehyde in various hair smoothing products at significant concentrations centered whether methylene glycol could legally be synonymous with formaldehyde. Anhydrous formaldehyde gas readily dissolves in and reacts with water to form an equilibrium solution of methylene glycol. When heated, the equilibrium shifts and favors the production of formaldehyde and water. Thus, the manufacturer of Brazilian Blowout argued that methylene glycol is in their products, not formaldehyde, and therefore they can claim that their product was formaldehyde-free. The first involves nomenclature. The second issue is the method by which formaldehyde concentration is measured. The third involves measurements of formaldehyde concentration in bottles of the product in which the reported concentration is dependent upon both the method of measurement and nomenclature. However, the company reached a settlement with the state of California and is no longer claiming their products are formaldehyde free.
Nomenclature The Chemical Abstracts Service (CAS) lists formaldehyde (50-00-0) and methylene glycol (463-57-0Methanediol) as two different substances. The compounds have two different chemical structures, exist in two different chemical families and exhibit different physical properties. Formaldehyde is a colorless gas with chemical structure HCHO. Formaldehyde is a listed carcinogen. NTP notes methylene glycol as the primary chemical form of formaldehyde in water. When heat is applied in the Brazilian blowout process causes the methylene glycol to dehydrate, yielding formaldehyde gas and water vapours. According to Golden and Valentini even in worst case experiments less than half of the methylene glycol result in measurable formaldehyde gas, also an unknown portion of this measurement is due to the combining of the volatilised methylene glycol being reported as gaseous formaldehyde, furthermore the reverse reaction is much more rapid and much more favourable at STP equilibrium, which is not taken into account in the analysis. They contend that the chemical equivalence assumption is incorrect.
Method of concentration measurement The Brazilian Blowout company (GIB LLC) has argued that Eastwood's lab and government labs in California and Oregon performed improper tests to determine formaldehyde concentration, arguing instead that an NMR spectroscopy test is superior.
Inclusion of methylene glycol as formaldehyde in reported measurements