Racial and ethnic disparities in biomarkers of exposure and potential harm among U.S. adult exclusive e-cigarette users: 2013–2019

Objective: Provide evidence on racial and ethnic differences in biomarkers of exposure from rising e-cigarette use among U.S. adults. Methods: Data were drawn from Waves 1–5 of the Population Assessment of Tobacco and Health study (September 2013-November 2019). Differences in biomarkers of exposure and potential harm (BOE/BoPH) across non-Hispanic (NH)-Whites, NH Blacks, Hispanic/Latinos, and NH others were examined using generalized estimation equations. Results: Among exclusive e-cigarette users, mean concentrations of BOEs/BoPHs were not significantly different across NH Blacks (n=97), NH others (n=122), and NH Whites (n=1062), after adjustment by wave, age, sex, education, exposure to the secondhand smoke, and the number of recent puffs. Compared to NH Whites, Hispanics (n=151) had lower concentrations of nicotine equivalents (0.5[0.2–1.7] vs. 15.5 [12.5–19.1] nmol/mg creatinine, p<.0001), cotinine (33.4[9.7–114.7] vs. 1008.3 [808.3–1257.9] ng/mg creatinine, p<.0001), and 4-(methylnitrosamino)−1-(3-pyridyl)−1-butanol (NNAL) (2.6[1.5–4.4] vs. 5.7 [4.9–6.6] pg/mg creatinine, p=.004), but similar concentrations of BOEs for heavy metals, polycyclic aromatic hydrocarbons, volatile organic compounds, and oxidative stress. Differences between Hispanics and NH Whites are expected, given different e-cigarette use profiles. Specifically, Hispanics were less likely to be daily vapers (49.4[35.1–63.8]% vs 81.3[77.7–84.5]%, p<.0001) and nicotine e-cigarette users (72.7 [64.0–79.9]% vs. 89.2 [86.4–91.5]%, p=.0002] and reported a lower number of recent puffs (mean[standard error]=16.7[3.6] vs. 28.6[2.0], p=.02] than their NH-White counterparts. Hispanic vapers were also less likely than NH Whites to have previously smoked cigarettes (49.7 [37.2–62.3]% vs. 88.5 [84.7–91.5]%, p<.0001]). Conclusions: Hispanic vapers exhibited lower exposure to nicotine metabolites and carcinogens than their non-Hispanic White counterparts. The harm reduction potential from e-cigarette use are likely to be realized across diverse racial and ethnic groups.