A small but growing literature studies how pollution makes it harder to think, in both academic and non-academic settings. Ebenstein et al. (2016) find that an increase in fine particulate pollution reduces scores on high-stakes tests in Israel (with a standard deviation increase in fine particulates lowering scores by 1.7% of a standard deviation), while Roth (2021) finds that particulate matter in classrooms reduces the scores of London-area university students. Zhang et al. (2018), examining a nationally representative survey in China, find a statistically significant effect on test scores of verbal ability.
Some evidence also suggests that pollution may not merely dim our mental acuity, but also lead to altered decision-making, sometimes in quite unexpected contexts. Several studies (Huang et al. 2020, Dong et al. 2021, Meyer and Pagel 2017) find that higher air pollution is associated with an increase in behavioural biases among investors and analysts in the financial sector, which appear to be linked to constrained attention and affect alterations. These findings potentially extend to a myriad of high-stakes situations and skilled service professions. Perhaps even more troubling is the possible link between air pollution and criminal activity. Herrnstadt et al. (2021) find that higher particulate matter concentrations lead to increases in violent crime across areas of Chicago (a one standard deviation increase in particulate matter raises violent crime by 2.9%); Burkhardt et al. (2019) estimate that a 10% reduction in daily PM2.5 and ozone in the US could save $1.4 billion in crime costs per year. Across the pond, Bondy et al. (2020) find that increases in the Air Quality Index (a measure of pollution) are associated with increased crime in London.1