Toxicological Assessment of Key Substances in UV-Curable Nail Coatings: HEMA, TMPTA, TPO, HQ, and MEHQ

Abstract

UV-curable nail coatings have gained widespread popularity due to their superior durability, gloss, and fast-curing properties. However, the use of (meth)acrylate monomers, photoinitiators, and inhibitors in these products raises concerns regarding consumer and occupational safety. This study examines the toxicological profiles and prevalence of five commonly used compounds in UV-curable nail formulations: 2-hydroxyethyl methacrylate (HEMA), trimethylolpropane triacrylate (TMPTA), diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), hydroquinone (HQ), and hydroquinone monomethyl ether (MEHQ). A combination of bibliographic review and UPLC-DAD analysis was used to assess their presence in commercial samples and evaluate health risks. Despite regulatory restrictions, all substances were detected in the tested formulations or raw materials. This study underscores the need for stricter regulatory enforcement, improved product labeling, and the development of safer alternatives in UV-curable cosmetic systems.