Urban Fine Particulate Matter and Elements Associated with Subclinical Atherosclerosis in Adolescents and Young Adults

The relationships between the elemental constituents ofPM2.5and atherosclerosis remain limited, especially in youngpopulations. This study included 755 subjects aged 12-30 years inthe Taipei metropolis. A land use regression model was used to estimateresidential annual mean concentrations of PM2.5and eight elementalconstituents. We evaluated the percent differences in carotid intima-media thickness (CIMT) with PM2.5and elemental constituentexposures by linear regressions. Interquartile range increments forPM2.5(4.5 mu g/m3), sulfur (108.6 ng/m3), manganese (2.0 ng/m3), iron(34.5 ng/m3), copper (3.6 ng/m3), and zinc (20.7 ng/m3) were foundto associate with 0.92% (95% confidence interval (CI): 0.17-1.66),0.51% (0.02-1.00), 0.36% (0.05-0.67), 0.98% (0.15-1.82), 0.74%(0.01-1.48), and 1.20% (0.33-2.08) higher CIMTs, respectively. Factor analysis identified four air pollution source-related factors,and the factors interpreted as traffic and industry sources were associated with higher CIMTs. Stratified analyses showed theestimates were more evident in subjects who were >= 18 years old, females, or who had lower household income. Our study resultsprovide new insight into the impacts of source-specific air pollution, and future research on source-specific air pollution effects inyoung populations, especially in vulnerable subpopulations, is warranted.