Cosmetovigilance in Hair Straighteners: Determination of Formaldehyde Content by Spectrophotometry and Label Evaluation

The aim of this work was to identify and quantify formaldehyde present in commercial hair straightening formulations, the application of cosmetovigilance from organoleptic/physicochemical tests and label analysis being approached. Samples A1, A3, A5, and A8 had a formaldehyde concentration ranging from 1.5 to 3.83% (w/v), corresponding to concentrations of 7.5, 16.45, 7.9, and 19.15 times higher than that allowed by the National Agency of Sanitary Monitoring (ANVISA), resulting in strong odor characteristic of this active substance. Of these samples, A3 and A5 did not indicate the presence of formaldehyde on the label besides ignoring the warning information and restrictions of use. The absence of the registration number granted by ANVISA for sample A5, which may be an indication of a clandestine product, was also verified. As to the organoleptic and physicochemical properties, only the A2 sample presented different viscosity and centrifugation results. In view of these results, it was concluded that 50% of the analyzed products were reproved because of the presence of formaldehyde out of the allowed concentration, being evident the importance of the implantation of cosmetovigilance system to guarantee the final quality of the cosmetic products, mainly in view of the safety and efficacy of these products.