After months of polemics over the safety of hair straighteners containing high concentrations of formaldehyde, the Cosmetic Ingredient Review Expert Panel (CIR), classified formaldehyde and methylene glycol as “unsafe under present conditions of use” in these products.

The CIR Expert Panel gathers scientists, dermatologists, pharmacologists and toxicologists, under the aegis of the U.S. Personal Care Products Council, with the mission to independently and scientifically assess the safety of ingredients used in cosmetics in the U.S. The Panel assessed the safety of formaldehyde and methylene glycol at the request of FDA, the Professional Beauty Association, and the Personal Care Products Council, after a succession of safety alerts regarding hair straightening treatments with high formaldehyde levels.

The Expert Panel noted that the safety of methylene glycol and formaldehyde in hair straightening products depends on a number of factors, including the concentration of formaldehyde and methylene glycol, the amount of product applied, the temperature used during the application process, and the ventilation provided at the point of use. The Panel concluded that under present practices of use and concentration, formaldehyde and methylene glycol are unsafe in hair straightening products. “In no case should the formalin [1] concentration exceed 0.2% (w/w), which would be 0.074% (w/w) calculated as formaldehyde or 0.118% (w/w) calculated as methylene glycol,” said the CIR.

Molecular structure of formaldehyde

Molecular structure of formaldehyde

CIR reached its conclusion after a comprehensive review of the available safety data and information and a robust discussion of this difficult and complex issue. We support the panel’s findings,” said Jay Ansell, Council scientist and vice president of cosmetic programs at the Personal Care Products Council.

The panel also concluded that formaldehyde and methylene glycol are safe for use as a preservative in cosmetics at minimal effective concentration levels and that do not exceed established limits and are safe in nail hardening products in the present practices of use and concentration (1 – 2%). [2] However, the Panel did note that “the present practices of use of nail hardeners do include instructions that admonish users to limit application of the material to the nail, allow it to dry fully, and to not get the material on the skin.

It is now up to the FDA to decide whether or not to restrict the use of these substances in cosmetic products placed on the US market.