Ribisl co-authors American Heart Association policy statement on e-cigarettes
Sept. 11, 2014
A policy statement newly released by the American Heart Association (AHA) says that electronic cigarettes, although safer than conventional cigarettes, pose a number of risks. The statement calls for continued monitoring of the health effects of electronic cigarettes, with special attention given to youth and adolescents.
Dr. Kurt Ribisl
The AHA policy statement, published Aug. 24 as an article in the journal Circulation, was authored by Kurt Ribisl, PhD, professor of health behavior at the Gillings School, and a team of researchers who recommend studying the impact of these new technologies on population health, cardiovascular disease and stroke.
E-cigarettes are battery-powered devices that turn a nicotine-infused liquid into an aerosol that is inhaled by the user. The aerosol does not contain smoke, tar or carbon monoxide and produces very low levels of air toxins.
As of 2014, 466 brands of e-cigarettes are widely available in retail stores and online, and sales are expected to exceed that of conventional tobacco cigarettes by 2017.
Ribisl and colleagues caution that use of e-cigarettes could be a problem at the population level. For instance, e-cigarettes could fuel and promote nicotine addiction, especially in children, and acceptance of the devices has the potential to renormalize smoking behavior. E-cigarette use also potentially could serve as a gateway to other drugs and harmful substances.
Most of the toxicity from e-cigarettes comes from the type of e-liquid (or e-juice) formulation and the specific design of the device. Typically, e-liquid formulations contain nicotine, flavors, water, glycerin and propylene glycol. Exposure to levels and types of metals such as tin, cadmium and copper or other materials within the aerosol depends on the material and other engineering features of the heating coils. Other materials in e-cigarettes could include ceramics, plastics, rubber, filament fibers and foams. Some of these materials can be aerosolized and inhaled.
According to the article, studies with e-cigarette liquids and aerosols indicate some cell toxicity related to flavoring chemicals, but not to nicotine content, which varies by brand. Nicotine blood levels generally are lower after smoking e-cigarettes than after smoking tobacco. However, the amount of nicotine has been either over- or under-estimated in studies, a fact that calls for more regulatory oversight.
No adverse health effects of e-cigarette use are known currently. Such effects likely would be less than those of smoking tobacco, but could be significant in individuals with heart disease. Acute nicotine toxicity is a concern if e-cigarette liquids are ingested, especially by children.
Ribisl and colleagues report that data on health effects to date, studied primarily in healthy people with short-term exposure, reveal little or no evidence of severe adverse effects. Respiratory irritation and bronchial constriction from a propylene glycol aerosol raise concerns about harm to people with asthma and chronic obstructive pulmonary disease. One small study reports benefit rather than harm when users reduce or quit smoking tobacco. There are no reports of e-cigarette safety in patients with known cardiovascular disease.
Secondhand exposure to e-cigarette aerosol exposes a nonsmoker to nicotine, particulates and several potentially toxic organic chemicals, but at much lower levels than from tobacco smoke. Nonsmokers still are exposed to some nicotine, and the regular use of e-cigarettes has the potential to substantially contaminate the environment with nicotine.
The article urges that e-cigarettes be included in smoke-free air laws and that use by minors be discouraged by laws that punish those who sell to minors, restrictions on marketing and advertising, and FDA regulation and taxing at a rate significant enough to deter purchases.
Ribisl and the team report that e-cigarettes represent a major change in the tobacco control landscape. The AHA plans to continue to monitor the effect of these new technologies on population health, cardiovascular disease and stroke and will give special attention to the effect on youth and adolescents.
Ribisl’s collaborators on the article are Aruni Bhatnagar, PhD, director of the Diabetes and Obesity Center and professor of cardiovascular medicine at the University of Louisville; Laurie P. Whitsel, PhD, director of policy research with the American Heart Association; Chris Bullen, PhD, director of the National Institute for Health Innovation and associate professor at the University of Auckland, New Zealand; Frank Chaloupka, PhD, distinguished professor at the University of Illinois-Chicago; Mariann R. Piano, PhD, professor of nursing and interim head of the bio-behavioral health sciences department at the University of Illinois-Chicago; Rose Marie Robertson, MD, of the American Heart Association; Timothy McAuley, PhD, founder and chief executive manager of Consulting for Health, Air, Nature and a Greener Environment; David Goff, PhD, dean of the Colorado School of Public Health; and Neal Benowitz PhD, professor of medicine and bioengineering at the University of California at San Francisco.
Gillings School of Global Public Health contact: David Pesci, director of communications, (919) 962-2600 or dpesci@unc.edu.
