Is painting your nails bad for you?

Painting your nails is a popular form of self-expression all around the world. But whether you prefer a French tip, emo black or long acrylics with eye-catching designs, you might wonder this: Can painting your nails be bad for you?

The answer is a bit complicated, but traditional nail polish, gel nails and acrylics are generally safe, Dr. Chris Adigun, a dermatologist at the Dermatology & Laser Center of Chapel Hill in North Carolina, told Live Science.

That said, traditional nail polishes can contain chemicals that can irritate the skin around the nail bed, and in some people, they can cause allergic reactions. For that reason, Adigun recommends using "three-free" nail polish, which lacks three chemicals that can often cause irritation: toluene, formaldehyde, and formaldehyde releasers, which release formaldehyde as they break down. Some nail polishes contain formaldehyde because it is an antimicrobial, preservative and nail hardener, while toluene helps nail polish remain liquid in the bottle but dry quickly on your nails.

Unfortunately, though, nail polishes marketed as lacking these ingredients aren't always labeled accurately. A 2019 study published in the journal Dermatitis examined 28 nail polishes advertised as formaldehyde-free and found that four still contained the chemical.

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The National Cancer Institute recognizes formaldehyde as a carcinogen, but studies have uncovered a strong link to the disease only in people who breathe in the chemical in high quantities, such as industrial workers and embalmers. This type of exposure to formaldehyde and other chemicals may increase the risk of some cancers in nail technicians, too, but research into that risk has turned up coNFLicting results.

It's not known whether formaldehyde is present in high enough levels in nail polish — or whether the body absorbs enough of it in this context — for the chemical to increase cancer risk through nail polish use, according to Harvard Health. There is a lack of research on how the chemical may affect people who frequently paint their nails.