Long-term exposure to outdoor pollution, mostly by exposure to fine particulate matter (with an aerodynamic diameter smaller than 2.5 μm; PM 2.5 ), was calculated to lead to 3.3 million premature deaths worldwide in 2010 (Lelieveld et al., 2015), and quantifications of ambient PM 2.5 -related health risks implied an annualized growth rate of 1.46% during 2010-2019 (C. J. L. Murray et al., 2020). Epidemiologic cohort studies have provided increasing evidence that PM 2.5 exposure increases the risk of premature death from health outcomes including chronic obstructive pulmonary disorder (COPD), ischemic heart disease (IHD), lower respiratory illnesses (LRI), lung cancer (LC), type-II diabetes (T2D), and