Understanding HEMA, HPMA, TPO, and Optical Brighteners

HEMA, or 2-hydroxyethyl methacrylate, is a common chemical found in many nail cosmetic products. Despite its small size, it can penetrate the skin barrier and enter the bloodstream, potentially causing allergic contact dermatitis (ACD) and other health issues. HEMA is widely recognized as a primary allergen in gel polish, often followed by HPMA, or 2-hydroxypropyl methacrylate. Allergic reactions to these substances can lead to nail detachment or severe red, itchy rashes, which may extend beyond the fingertips to areas in contact with the nails, such as the eyelids, face, neck, and genital region. In rare instances, respiratory issues may arise.

In 2018, the British Association of Dermatologists raised concerns about a surge in allergies linked to artificial nail enhancements. They referred to a comprehensive study involving 4,931 participants conducted in 2017, which identified HEMA as the primary (meth)acrylate compound responsible for allergic sensitization, followed by HPMA. Acknowledging the increased risk associated with improper application, the European Commission mandates clear warnings such as "For professional use only" and "Can cause an allergic reaction" on the packaging of nail products containing HEMA.

TPO, or trimethylbenzoyl diphenylphosphine oxide, is commonly found in gel nail polish to initiate the curing process under UV light exposure. According to a 2014 paper by the Scientific Committee on Consumer Safety, an independent body of the European Commission, TPO is considered safe for use as a nail modeling product at concentrations up to 5.0%. However, the committee classifies TPO as a moderate skin sensitizer, indicating its potential to trigger allergic reactions in certain individuals upon skin contact.

Optical brighteners are commonly added to enhance the color of gel nail polish, but they may trigger allergic reactions when they come into contact with the skin, potentially leading to skin irritations. Further research is needed to fully understand the long-term effects of these chemicals. Opting for products without optical brighteners can help minimize the risk of adverse reactions and is a wise choice, particularly for individuals with sensitive skin.