Fine particulate matter (PM2.5) has been linked to aging
risk, and a lack of knowledge about the relationships between PM2.5 components and aging risk impeded the development of healthy
aging. Participants were recruited through a multicenter cross-sectional
study in the Beijing–Tianjin–Hebei region in China.
Middle-age and older males and menopausal women completed the collection
of basic information, blood samples, and clinical examinations. The
biological age was estimated by Klemera–Doubal method (KDM)
algorithms based on clinical biomarkers. Multiple linear regression
models were applied to quantify the associations and interactions
while controlling for confounders, and a restricted cubic spline function
estimated the corresponding dose–response curves of the relationships.
Overall, KDM-biological age acceleration was associated with PM2.5 component exposure over the preceding year in both males
and females, with calcium [females: 0.795 (95% CI: 0.451, 1.138);
males: 0.712 (95% CI: 0.389, 1.034)], arsenic [females: 0.770 (95%
CI: 0.641, 0.899); males: 0.661 (95% CI: 0.532, 0.791)], and copper
[females: 0.401 (95% CI: 0.158, 0.644); males: 0.379 (95% CI: 0.122,
0.636)] having greater estimates of the effect than total PM2.5 mass. Additionally, we observed that the associations of specific
PM2.5 components with aging were lower in the higher sex
hormone scenario. Maintaining high levels of sex hormones may be a
crucial barrier against PM2.5 component-related aging in
the middle and older age groups.