A 3.26x (albeit with very wide CI) increase in Alzheimer's incidence for each 10 µg/m³ increase in long-term PM2.5 exposure? "Short- and long-term PM2.5 exposure was associated with increased risks of stroke (short-term odds ratio 1.01 [per µg/m³ increase in PM2.5 concentrations], 95% CI 1.01-1.02; long-term 1.14, 95% CI 1.08-1.21) and mortality (short-term 1.02, 95% CI 1.01-1.04; long-term 1.15, 95% CI 1.07-1.24) of stroke. Long-term PM2.5 exposure was associated with increased risks of dementia (1.16, 95% CI 1.07-1.26), Alzheimer's disease (3.26, 95% 0.84-12.74), ASD (1.68, 95% CI 1.20-2.34), and Parkinson's disease (1.34, 95% CI 1.04-1.73)." – Fu et al 2019.