“…The contributions of each source for the participants, which were reported in our previous publication (N. Zhang et al., 2022 ), were separately accounted as independent variables in the linear regression models, while the inflammatory cytokines were dependent variables. All models were adjusted for confounders, including body mass index, sex, age, smoking status (active smoker, passive smoker, and non‐smoker), education (high school and below vs. college and above), relative humidity and outdoor temperature on the day of sample collection.…”