Starting from September 1, the European Union (EU) has prohibited the use of a common ingredient in gel nail polish, trimethylbenzoyl diphenylphosphine oxide (TPO). TPO is known for giving nails a glossy finish and enabling a quick drying time under UV or LED light. Gel nail polish, which has been popular since the 2000s, is a type of nail polish that hardens under UV or LED light, creating a durable layer on the nails. However, the EU has deemed TPO toxic after several studies indicated that it could lead to fertility problems and negatively impact reproductive health.
Gel nail polish, unlike traditional nail polish, provides a long-lasting and high shine finish that resists chipping and peeling, sometimes for several weeks. While not all gel polishes contain TPO, many do. The EU, which has previously banned certain chemicals still legal in the US, including BHA and BHT in several countries, as well as a “yoga mat” bread ingredient, has deemed the health risks of TPO too high, labeling it “carcinogenic, mutagenic or toxic to reproduction.”
Some experts suggest that the ban is more of a precautionary measure than a preventive one, as the evidence linking TPO to adverse health outcomes is primarily based on animal studies. Dr. Hannah Kopelman, a dermatologist at DermOnDemand, stated that the EU is banning TPO out of caution, as there are not yet large-scale human studies proving harm, but the potential risks were enough to warrant stricter regulation.
TPO is also used as a photoinitiator in dental fillings, but the European ban only applies to cosmetic ingredients. Before the ban, the ingredient was only available for professional use, and at a maximum concentration of 5%. Now, the sale, marketing, and use of products that contain it will be entirely prohibited. Nail salons will have to dispose of any existing stock, with “no exceptions, no time limit for selling products.”
The EU announced its initial decision in May 2024, with the ban date revealed earlier this summer. However, importers and beauty professionals have expressed concern that the September 1 ban date does not provide enough time for them to replace their stock with TPO-free products. TPO is currently unregulated in the United States. Consumers concerned about the potential dangers can reduce their risk by requesting TPO-free nail products, allowing ample time between gel manicures, using a protective base coat, and ensuring the application is made in a well-ventilated space.
Research indicates that more than 100 million US women use some sort of nail product, and TPO is not the only factor gel enthusiasts should be wary of. Podiatrist Dr. Saylee Tulpule has warned that the UV light used to cure the polish may increase the risk of skin cancer, while “thinning or weakening the nail plate before applying the durable gel color” can damage the nail. While waiting between salon appointments can help offset the risk of TPO exposure, allowing gel nails to “grow out” comes with its own set of dangers, mainly a pathogen known as Pseudomonas bacteria that causes the nail to turn green or blue.
While this type of bacteria is typically not life-threatening for a healthy individual, those with underlying health conditions or impaired immune systems could face lethal consequences. The bacteria can cause infections in the chest, urinary tract, ears, eyes, skin, blood, and more.