Expert Panel for Cosmetic Ingredient Safety

Scientific data supporting the safety of styrene and vinyl-type styrene copolymer ingredients used in cosmetics and personal care products was thoroughly reviewed by the Expert Panel for Cosmetic Ingredient Safety (formerly the Cosmetic Ingredient Review Expert Panel). The Expert Panel concluded that the following 35 styrene and vinyl-type styrene copolymers are safe in the present practices of use and concentration in cosmetics:

* Also considered safe, but not reported to be in current use. Were these ingredients to be used in the future, the expectation is that they would be used in product categories and at concentrations comparable to others in this group.

U.S. FDA

Styrene is listed among the synthetic flavoring substances and adjuvants that may be safely used in food (21CFR 172.515). Polystyrene may be safely used as a component of articles intended for use in contact with food (21CFR177.1640). Butadiene-styrene rubber (styrene/butadiene copolymer) is included on the list of multiple FDA-approved direct food additive uses (e.g, 21CFR172.615 among others).

Expert Panel Review (2014)

After considering the large molecular sizes of these ingredients, the Expert Panel agreed that absorption through the skin is not expected.  The  available chemical characterization of these ingredients and toxicity tests provided the Expert Panel with a sufficient basis to assess the safety of these polymers as used in cosmetics.

Styrene monomer, a component of all of the copolymers reviewed in the safety assessment, and 1,3-butadiene monomer, a component of only three of the copolymers, are classified by regulatory agencies as carcinogenic in animals and in humans. Taking into consideration ingredient use concentrations and the data on low residual monomer content in the ingredients, the Expert Panel agreed that levels of residual styrene or 1,3-butadiene in cosmetic products would be substantially below levels of concern.

The Expert Panel also discussed the potential for incidental inhalation exposures to these ingredients from products that are sprayed or in powder form. Based on likely airborne particle size distributions, concentrations in the breathing zone, ingredient use concentrations and negative results in toxicity tests, the Expert Panel agreed incidental inhalation would not lead to respiratory effects or systemic toxic effects.

The styrene and vinyl-type styrene copolymers reviewed by the Expert Panel are all listed in the EU’s Cosmetic Ingredient Database (CosIng) and may be safely used y under the rules governing cosmetic products in the European Union. For the ingredients polyacrylates-2, 7, 10, 11 and 13, the maximum residual acrylamide content in the finished product must be <0.1 mg/kg for body leave-on products and <0.5 mg/kg for all other cosmetic products.