Pollution and Mortality in the United States: Evidence from 1972-1988

We estimate the effect of sulfur dioxide (SO2) exposure on US population mortality over the period 1972-1988. Using changes in wind direction as an instrument for daily SO2 levels, we show that acute pollution exposure produces both short-run mortality displacement as well as delayed mortality effects in the month following exposure. On net, we estimate that a one-day, one part-per-billion increase in SO2 raises monthly mortality by 0.18 deaths per million. We then incorporate our estimates into a dynamic production model of health to quantify the lifelong effects of chronic pollution exposure. Model calculations of the effect of a permanent one-unit increase in SO2 exposure are 5-12 times larger than a simple linear scaling of the IV estimates of acute exposure.