Fig. 3
Bivariate thin-plate smoothing spline of longevity measures relative to median income and PM2.5. Panels a and b present the relationship between exceptional aging relative to median income and PM2.5 for the unadjusted and fully adjusted models, respectively. Panels c and d present the relationship between life expectancy relative to median income and PM2.5 for the unadjusted and fully adjusted models, respectively. Unadjusted models exclude controls for smoking and obesity, while full models include these controls