Some gel nail polishes banned in Europe

(CNN) - The European Union has banned the use of a key chemical ingredient in certain gel nail polishes and other cosmetic products.

Regulators have classified the chemical, known as TPO, as a type of reproductive toxicant.

TPO responds to light, and it helps gel nail polish set under ultraviolet light.

Some people may prefer gel nail polishes over regular nail polishes because the texture is harder, faster-drying and will generally last longer.