Nicotine concentration is a key characteristic of modern e-cigarette products. This study aims to illuminate age-related differences and temporal trends in nicotine concentrations to help inform strategies to reduce nicotine-related public health risks.
Data were drawn from the US Population Assessment of Tobacco and Health Study Wave 5 (December 2018–November 2019), Wave 6 (March–November 2021) and Wave 7 (January 2022–April 2023) and analysed in 2026. ² tests and multivariable regressions were used to compare nicotine levels used in e-cigarettes (ie, unknown, 0%, 0.1–1.7%, 1.8–4.9%, 5.0%+) by age groups at Wave 7 and examine trends in nicotine concentrations for adults (18+) across Waves 5–7.
Among individuals currently using e-cigarettes at Wave 7 (n=3782), about 60.1% of those aged 12–14 and 51.2% of those aged 15–17 reported not knowing nicotine concentrations, and young adults aged 18–24 were the most likely to report using 5.0%+ (38.7% prevalence vs 24.4% of those aged 25–34, 14.6% of 35–54 and 4.3% of 55+). The proportion of adults responding ‘I don’t know’ increased from 15.8% at Wave 5 to 23.8% at Wave 7, especially among those aged 18–24 (13.9–26.0) and 25–34 (13.9–23.6%). The proportion of adults reporting 5.0%+ increased from 13.9% to 24.4%(p<0.0001), and those reporting 0.1–1.7% decreased from 49.2% to 35.4% (p<0.0001).
Over half of youth using e-cigarettes were unaware of the nicotine concentration. High-concentration products have become increasingly prevalent, especially among young adults. Clearer nicotine concentration labelling on e-cigarette products and continued surveillance of nicotine levels are needed.