While proponents continue to say that e-cigs are safe, a new study shows that e-cigs may be just as dangerous as regular cigarette smoking—with the added danger of explosions that can mutilate and disfigure teens and adults using the systems. The newest study measures five chemicals in e-cigarettes known to cause bladder cancer, including “nitrosamines” and formaldehyde. The chemicals are known to be ingredients in e-cigarette liquid.

Dr. Sam Chang, a professor of urologic surgery at Vanderbilt-Ingram in Nashville, released results showing that even after discontinuing e-cigarette use for six months, 92 percent of e-cigarette users tested positive for two of the five chemicals known to cause bladder cancer. Results showed that e-cigarette use “induces Tumorigenic DNA adducts” (in bladder mucus) and “inhibits DNA repair in urothelial cells” (the lining of the bladder).

This new evidence contradicts the claims of the e-cigarette industry that e-cigarette smoking is safe. The safety claims are not surprising given industry value of the e-cigarette is in the billions and major involvement by big tobacco companies. The truth is that neither smoking cigarettes nor smoking e-cigarettes is a healthy choice. The difference is that e-cigarette risks are only now becoming news—including the risk of explosions due to possible product manufacturing defects.