Acute effects of short-term exposure to ambient air pollution on reproductive hormones in young males of the MARHCS study in China

Abstract Air pollution, which is associated with male reproductive health. However, it is unknown the acute effects of ambient air pollutants exposure on male reproductive hormones. The current study, we measured serum levels of reproductive hormone in 2030 blood samples gathered from The Male Reproductive Health in Chongqing College Students (MARHCS) cohort study. We derived a full coverage of ambient air pollutant (PM10, PM2.5, SO2, NO2, CO and O3) concentrations by employing machine learning algorithms, and used a mixed-effect model to estimate single-day and cumulative effects of air pollutants exposure on serum reproductive hormones. Our results showed that (1) PM10 and PM2.5 concentrations were positively associated with estradiol (E2) in both single and cumulative lag days, but were negatively associated with the ratio of Testosterone/E2 (the T/E2 ratio). NO2 was positively associated with estradiol at lag day 2 (95% CI: 0.290, 0.881; corrected P = 0.048) and lag 0–2 days (95% CI: 0.523, 1.337; corrected P = 0.003), with progesterone (P) at lag day 2 and lag day 3 (corrected P