Manufacturers often market e-cigarettes as a safer alternative to combustible tobacco products, and many teens believe e-cigarettes are safe. But new research provides more evidence about the risks of these products.

A study in the April 2018 issue of Pediatrics, “Adolescent Exposure To Toxic Volatile Organic Chemicals From E-Cigarettes,” (published online March 5) examined the levels of volatile organic compounds in urine of three groups of teens: those who exclusively used e-cigarettes, dual users of both e-cigarettes and traditional cigarettes, and those who did not smoke at all.

Researchers tested for volatile organic compounds known to be toxic, including propylene oxide, acrylamide, acrylonitrile, and crotonaldehyde. Those who used e-cigarettes had up to three times greater amounts of five volatile organic compounds in their urine, compared to teens who did not use e-cigarettes at all. Dual users had levels up to three times higher than the e-cigarette only group. Fruit flavored e-cigarette products produced significantly higher levels of acrylonitrile, which is a concern for teens because fruit flavors were the most popular choice and acrylonitrile is a known carcinogen.

Fifty-five percent of teens who used only e-cigarettes, and 67% of dual users reported using fruit flavors most often. The researchers conclude that just as with traditional cigarettes, messaging to teens must include warnings about the potential risk of toxic exposure to carcinogenic compounds when using these products.