Formulators take note: Zinc oxide and potassium hydroxide will be approved for use in cosmetics and personal care products under certain new European Union guidelines beginning May 21.
Zinc Oxide as a UV Filter
According to a recent amendment, the European Commission said zinc oxide (CAS# 1314-13-2, EC# 215-222-5) in non-nano and nano forms will be authorized for use as a UV filter in cosmetic products at a maximum concentration of 25%, except in applications that may lead to exposure of the consumer's lungs by inhalation, effective May 21.
Previously, an opinion on June 25, 2003 (4), stated that, in general, zinc oxide may be considered as a non-toxic substance, including when used in cosmetic products. However, at the time, the potential for absorption by inhalation was not considered and the Scientific Committee on Consumer Product (SCCP) expressed concern on the safety of micronized zinc oxide, which had been under scrutiny.
Also effective May 21, potassium hydroxide (CAS# 1310-58-3; EC# 215-181-3), known as POK, is authorized for use in cosmetic products that remove or soften calluses, up to a maximum concentration of 1.5% weight by weight (w/w).
According to the most recent update, as of publication, product labels that fall into this category must include a warning label that says, "contains alkali, avoid contact with eyes, keep out of reach of children and read directions for use carefully."
Read more about potassium hydroxide's numerous applications and formulating with zinc oxide in sunscreens in C&T.