“…Particle-size fractions PM 10 (suspended PM with an aerodynamic diameter < 10 μm) and especially the smaller ones (PM 2.5 and PM 1 , with aerodynamic diameters less than 2.5 and 1 μm, respectively) pose a significant health problem because they can penetrate the lungs and even the bloodstream [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ]. For an estimation of population-weighted exposure to ambient particulate air pollution, the average levels of PM 2.5 particle fraction concentrations are most commonly used, as this fraction is capable of penetrating deep into the lungs and causing severe, negative health effects [ 27 , 28 , 29 ]. However, the choice of fraction often depends on the availability of air pollution data.…”