Carcinogens found in the urine of cigarette smokers were also found in the urine of e-cigarette smokers, reports Medscape. 

Previous studies of traditional cigarette smokers have identified otoluidine and 2-naphthylamine as the two most carcinogenic molecules for the bladder, Dr Fuller said.

In the new study, 12 of the 13 e-cigarette users whose urine was analyzed had both otoluidine and 2-naphthylamine detected (limits of detection were 100 ng/mL and 10 ng/mL, respectively). None of the 10 controls were positive for the compounds.

Specifically, among e-cigarette users, there were 2.3-fold mean concentration level increases for otoluidine (P = .0013) and a 1.3-fold increase for 2-naphthylamine (P = .014) compared with controls.

Notably, all study participants, when interviewed by investigators, said that e-cigarettes were “safe.”

Dr Fuller also commented that, among traditional cigarette smokers, the urine levels of these molecules would be “greater.”