Effects of Short-Term Measures to Curb Air Pollution: Evidence from Santiago, Chile

It is well established that exposure to high levels of air pollution in the short term leads to negative health outcomes; yet there exist very few policies intended to address short run spikes in air pollution. In this article we examine a policy implemented by the Government of Chile that uses temporary measures to reduce the severity and negative health impacts of poor air quality in the short run. This policy involves the announcement of "Environmental Episodes" on days forecast to have particularly poor air quality. Such Episode announcements trigger a number of government protocols and public notices intended to both improve regional air quality and encourage avoidance behaviors among the populace. By comparing days on which Episodes were announced to observationally similar days before the policy was fully implemented, we demonstrate that the announcement of an Environmental Episode reduces ambient concentrations of particulate matter in the Santiago Metropolitan Region by approximately 20% on the day of implementation, with effects persisting into subsequent days. We also find that the temporary restrictions, government actions, and informational campaigns that make up an Episode reduce mortality among the elderly on the day-of and days-after Episode implementation. Our findings suggest that the Environmental Episode program effectively addresses poor air quality in the short term and could serve as a valuable model for policymakers seeking to augment long-term air quality strategies with a means of addressing temporary spikes in local or regional air pollution levels.