A high percentage of urine samples from electronic cigarette users tested positive for two known bladder carcinogens, according to results of a pilot study presented at the American Urological Association’s Annual Meeting.
The findings suggest a potential link between e-cigarettes and bladder cancer development.
Prior research has established traditional cigarette smoking as a risk factor for bladder cancer.
E-cigarettes have become a popular alternative to traditional cigarettes based on speculation that they are safer. However, previous studies have shown the liquid used in e-cigarettes may contain various bladder carcinogens, such as nitrosamines, formaldehyde, acrolein, metals and acetaldehyde.
Thomas Fuller, MD, urologic surgeon at UPMC Presbyterian in Pittsburgh, and colleagues collected urine samples from 13 e-cigarette users (mean age, 39.4 years; 60.2% male) and 10 nonsmokers who served as controls. Investigators assessed the samples for presence of five molecules identified as bladder carcinogens: benz(a)anthracene, bezno(a)pyrene, 1-hydroxypyrene, o-toluidine and 2-naphthylamine.
All samples were acidified, hydrolyzed, extracted, dried and resuspended for LC-MS analysis.
The e-cigarette users reported a mean 19.9-year history of traditional cigarette smoking, at a mean rate of 1.3 packs per day. However, e-cigarette users reported abstaining from smoking traditional cigarettes for a minimum 6 months prior to study enrollment.
Their mean duration of e-cigarette use was 26 months. Approximately 84% of e-cigarette users reported use of more than 28 e-cigarettes per week, and mean e-vape nicotine concentration was 6.8 mg/mL.
Urine samples from 12 of the 13 e-cigarette users tested positive for o-toluidine (limit of detection, 100 ng/mL) and 2-naphthylamine (limit of detection, 10 ng/mL). No samples from controls tested positive for these compounds (Fisher’s exact test = 0.0069).
Testing did not detect the other three carcinogens in any samples.
“Further study is needed to clarify the safety profile of e-cigarettes and their contribution to the development of bladder cancer given the greater concentration of carcinogenic nitrosamines in the urine of e-cigarette users in this pilot study,” Fuller and colleagues wrote. – by Melinda Stevens
Fuller T, et al. Abstract MP88-14. Presented at: American Urological Association Annual Meeting; May 12-16, 2017; Boston.
Disclosures: HemOnc Today could not confirm the researchers’ relevant financial disclosures at the time of reporting.