Chemical evaluation of electronic cigarettes

Area of Science:

• Analytical Chemistry
• Toxicology
• Public Health

Background:

• Electronic cigarettes (e-cigarettes) are battery-powered devices that deliver nicotine through an inhaled aerosol.
• Concerns exist regarding the chemical composition of e-cigarette liquids and emissions, and their potential health effects.

Purpose of the Study:

• To systematically review and evaluate the chemical constituents found in e-cigarette refill solutions, cartridges, aerosols, and environmental emissions.

Main Methods:

• Conducted systematic literature searches across 5 databases using 11 search terms (January 2007–September 2013).
• Analyzed 29 relevant articles from an initial yield of 36 studies.
• Identified chemicals including nicotine, TSNAs, aldehydes, metals, VOCs, and solvent carriers.

Main Results:

• Significant variability in chemical levels (nicotine, TSNAs, aldehydes, metals, VOCs, flavors, solvent carriers, tobacco alkaloids) across e-cigarette products.
• Inconsistent nicotine delivery and release of harmful substances (TSNAs, aldehydes, metals) among different e-cigarette products.
• Discrepancies between labeled and measured nicotine content; presence of phenolic compounds, PAHs, and drugs reported.
• Variability in particle size distribution and aerosol generation/analysis methods across studies.

Conclusions:

• Reliable quantification of e-cigarette aerosol constituents requires standardized methods for aerosol generation and chemical analysis.
• Understanding user behavior is crucial for accurate chemical measurements.
• Further research is needed to compare e-cigarette aerosol constituents with traditional cigarette smoke to evaluate toxicity potential.