Why is this BAD for me?
Formaldehyde or formaldehyde releasers (such as Bronopol, imidazolidinyl urea, DMDM hydantoin, quaternium-15, or diazolidinyl urea) can be present in hair treatments such as a Brazilian blowout or a keratin treatment. In these therapies, formaldehyde is used as a preservative. These substances are believed to be absorbed by the skin and are carcinogenic. They have also been linked to hair loss, scalp burns and skin irritation.