Knowledge Gaps Found in E-Cig Safety

Effects of electronic cigarettes were unclear in recent study

/ Author:  / Reviewed by: Robert Carlson, M.D Beth Bolt, RPh

(RxWiki News) Electronic cigarettes are booming in popularity and sometimes touted as a helpful tool for quitting smoking. But, because they are relatively new, there is limited knowledge about their health effects.

A new study highlights knowledge gaps regarding both the long- and short-term effects of so-called e-cigs.

"Talk to an addiction specialist about how to quit smoking."

The study was written by Alison Breland, PhD, of the Center for the Study of Tobacco Products at Virginia Commonwealth University in Richmond, and colleagues.

Dr. Breland and team reviewed existing research about the medical implications of e-cigs.

E-cigs, as opposed to traditional cigarettes, deliver nicotine by vaporizing a nicotine solution that the user inhales. Nicotine is the addictive chemical in tobacco.

The often-flavored nicotine solutions are available in different concentrations. The idea is that users can gradually reduce the amount of nicotine as they work toward quitting.

The authors found that the variety of nicotine solutions represented part of the lack of knowledge related to e-cigs.

“The actual nicotine concentrations may differ from the product labeling,” the authors wrote.

Solutions covered in the review contained from 0 to 36 milligrams of nicotine per milliliter. Some were labeled to indicate high, medium or low concentrations — despite a lack of standard definitions for those levels.

The authors also found a risk to children because some of the solutions had flavors suggesting candy, desserts or fruit.

The study authors also found that some e-cig solutions contained other potentially dangerous ingredients like propylene glycol and vegetable glycerin, referred to as humectants.

“Unfortunately, there are no data concerning the effects on the human lung of hundreds of daily inhalations of these humectants over the course of many years,” the authors wrote.

Analysis of the vapor from e-cigs, as compared to traditional cigarette smoke, showed the presence of similar hazardous toxins. However, the authors found that toxin concentrations were from 9 to 450 times lower in e-cigs than in traditional cigarettes.

The researchers found a lack of large-scale and long-term data on how effective e-cigs were at helping users quit smoking.

They reviewed five studies. One included 40 smokers who didn’t want to quit, with 27 completing the study. Of that group, 23 percent quit smoking. About 30 percent cut their smoking frequency by half.

In another study, participants using e-cigs reduced their use of cigarettes by 44 percent in one week.

"Very little is known about the acute and longer-term effects of [e-cig] use for individuals and the public health, especially given the dramatic variability in [e-cig] devices, liquids, and user behavior," the study authors wrote.

The researchers noted that more research would help clarify these findings. Because the data was limited, the researchers warned against generalizing about e-cigs.

The research was published online Aug. 5 in the Journal of Addiction Medicine.

Funding was provided by the National Institute on Drug Abuse and the US Food and Drug Administration' Center for Tobacco Products. The authors did not disclose any conflicts of interest.

Review Date: 
August 6, 2014
Last Updated:
August 7, 2014