An AIHA white paper published in October describes the potential exposures and health risks associated with the use of electronic cigarettes. The white paper reviews current scientific information, evaluates the effects of chemicals used in e-cigarettes and emitted from them, and indicates that although e-cigarettes may be “safer” for the user than tobacco cigarettes, they can emit airborne contaminants that may affect both the user and people nearby. 
“Vaping has been promoted as a smoking cessation tool that has no smoke,” said Cheryl (Cheri) L. Marcham, PhD, CIH, CSP, CHMM, project team leader on the white paper. “However, research indicates that emissions from vaping may contain nicotine and other contaminants whose health effects have not been thoroughly studied.”
E-cigarettes deliver vaporized nicotine and other chemicals to users. They have been shown to emit aerosols and several organic compounds, including nicotine, acetone, acrolein, formaldehyde, and flavoring compounds.
Nicotine-containing vapor from e-cigarettes may cause exposure for people around users. Exposure to even low levels of nicotine can increase heart rate, respiratory rate, and blood pressure. It can also cause birth defects, promote tumor growth, and affect brain development. 
Another chemical, propylene glycol, found in theatrical smoke, is commonly used in e-cigarettes as a carrier for nicotine and the flavorings, and to create the “vapor” that is emitted. The literature reviewed indicates that exposure to theatrical fogs may contribute to asthma and other lung problems. 
Limited information is available on the health effects of exposure to aerosolized flavorings. A compound that may be safe when ingested is not automatically safe when inhaled as an aerosol, as has been seen with the use of diacetyl for buttery flavorings. Most flavorings in e-cigarettes have not been thoroughly studied for inhalation health effects. 
E-cigarettes are not emission-free, and limited scientific information exists on their potential health risks. Risk assessment methods that examine the costs and benefits of e-cigarettes may be more useful than quantitative health risk assessments. According to the white paper, the only group that may benefit from e-cigarette use consists of people who already smoke and who want to reduce their exposure to byproducts of combustion. For other people, however, no clear benefits have been demonstrated, and there may be health risks, especially for vulnerable populations. These include children, pregnant women, and people with cardiovascular or lung conditions.
“While e-cigarettes may appear to provide a ‘safer’ alternative to tobacco cigarettes, these products have been shown to emit airborne contaminants that may be inhaled by both the vaper and those nearby,” said Marcham. “As a result, the project team concluded that e-cigarettes should be considered a source of organic compounds and particulates in the indoor environment until they have been thoroughly evaluated for safety.”
The white paper is the product of collaboration between AIHA’s Indoor Environmental Quality and Risk Assessment committees and is available at
AIHA Cautions Against Indoor Use of E-cigarettes in New White Paper