I guess this is the worst horror story I have seen regarding BKT
http://www.associatedcontent.com/article/478875/brazilian_hair_straightening_fabulous.html?cat=69
Fad Hair Treatment Responsible for at Least One Death
Brazilian Hair Straightening is the hottest fad to hit beauty salons since, well, Brazilian waxing. Touted as a more natural, cheaper and less labor intensive process than Japanese hair straightening, stylists who perform this service claim it uses keratin, a natural protein, to soften, smooth and straighten hair. Before and after photos used as promotions for the treatment feature models with shiny, pin-straight tresses. The truth is, Brazilian Hair Straightening, also known as Brazilian Keratin Treatment, really does work as advertised. The only problem is, the part they don't tell you is that it can kill you!
While keratin is indeed an ingredient in the formulas used to perform Brazilian Hair Straightening, the true active ingredient is formaldehyde (as in embalming fluid). Formaldehyde is known to be an aggressive carcinogen, and its fumes are extremely dangerous. Heat and moderate humidity levels accelerate the noxious effects of the chemical. Since the Brazilian Hair Straightening treatment also involves applying heat to the hair with a straight-iron, stylists who perform it are in danger, and are cautioned to wear gas masks and latex gloves and perform the procedure in an area with ventilation. Even with these precautions the FDA considers any solution containing more than .02% formaldehyde to be patently unsafe. They don't regulate the formulas, however, most of which are manufactured in Latin America, and the higher the percentage of formaldehyde, the more effective a straightener the treatment is. Random testing performed by Allure Magazine indicated that some salons were using solutions that contained as much as ten times the safe amount.
Brazilian Keratin Treatments aren't dangerous only to the stylist. It is theorized that repeated treatments will cause formaldehyde buildup in the hair, releasing formaldehyde fumes every time a patron blow dries or hot-irons her hair. There has been at least one documented death from the treatment. In March 2007, a 33 year old Brazilian woman actually died from the process. Anvisa, Brazil's National Health Surveillance Agency, believes that an excess of noxious fumes were released from the heat when she took a shower after leaving the solution in her hair for 4 days. Is straight hair worth dying for? That should be a rhetorical question.
When news reports of the potentially fatal consequences of this treatment hit the mass media through an article in Allure Magazine and a report on CBS News' "The Early Show," however, it only seemed to give the process illicit appeal for some women in fashion-conscious cities with large Brazilian populations. In Miami, for example, newspapers and local craigslist sites feature numerous classified ads advertising Brazilian Straightening, often touting the fact that the solution is "the highest concentration available." In many cases, these ads refer to treatments done in homes of individuals who are not even licensed cosmetologists, and the perceived benefit to the client is more straightening power for less money. But by using embalming fluid on her hair, they may be hastening her and themselves to the grave.
Sources:
www.cbsnews.com
December 6, 2007 Time Out New York Magazine, "Scared Straight" by Rachel