Air Pollution and Covid-19

Principal Investigator: Valentina Bosetti

The Paper: "Social distancing measures following COVID-19 epidemics had positive environmental consequences" by Valentina Bosetti, Maurizio Malpede and Marco Percoco

A burgeoning literature in economics and in the medical sciences attributes deterioration in health status to exposure to airborne pollutants. Particulate matter is known to increase mortality rates and hospitalizations for respiratory and heart-related illnesses, in particular among vulnerable groups (e.g. Pope and Dockery (2006); Schlenker and Walker, 2016; Deryugina et al., 2019). A growing body of research also makes causal links between fine particulate matter and physical and cognitive productivity (e.g. Graff Zivin and Neidell, 2012, Zhang et al., 2018).

Policy makers face uncertainty over the anticipated effects of policy interventions aimed at reducing air pollution in urban areas - such as traffic restrictions - because of the complex natural processes underlying the phenomenon.

The sudden halt on population movements and production in Italy provides a unique natural experiment for assessing:

  • The sensitivity of local air pollution to emissions. To lower sensitivity correspond greater social costs of air pollution abatement.
  • Distinguishing the heterogeneous contribution to local air pollution of different sectors. This is required for pollution reduction policies, as emission abatement costs vary by sector.

We approach these tasks by assembling an interdisciplinary team of economists, environmental engineers and the Regional Agency for the Environment (ARPA) of Lombardy.

In a first step we estimate the causal change in the concentrations of a major pollutants induced by the lockdown of the Lombardy Region starting from a counterfactual model based on weather variables. The partnership with ARPA - yet under development - is meant to leverage on scientific expertise of pollution modelers to improve the counterfactual.

In a second step we will link, where possible, the trend in emissions to sectors (residential, traffic, non-residential buildings, industry, agriculture, imported pollution). This will require estimating changes in emissions by sector; data on mobility and economic activity will be of particular relevance and might need to be purchased.


  • Chang, T. Y., Graff Zivin, J., Gross, T., and Neidell, M. (2019). The Effect of Pollution on Worker Productivity: Evidence from Call Center Workers in China. American Economic Journal: Applied Economics, 11(1):151-172.
  • Deryugina, T., Heutel, G., Miller, N. H., Molitor, D., and Reif, J. (2019). The Mortality and Medical Costs of Air Pollution: Evidence from Changes in Wind Direction. American Economic Review, 109(12):4178-4219.
  • Graff Zivin, J. and Neidell, M. (2012). The Impact of Pollution on Worker Productivity. American Economic Review, 102(7):3652-3673.
  • Pope, C. A. I. and Dockery, D. W. (2006). Health Effects of Fine Particulate Air Pollution: Lines that Connect. Journal of the Air & Waste Management Association, 56(6):709-742
  • Schlenker, W. and Walker, W. R. (2016). Airports, Air Pollution, and Contemporaneous Health. The Review of Economic Studies, 83(2):768-809.

Vulnerability to Covid-19 and Fine Particulate Matter

Medical and economic literatures have provided substantial evidence of the detrimental effects of fine particulate matter (PM 2.5) on the cardio-pulmonary system. Toxicological and epidemiological studies have linked PM to viral infections, including Covid-19 (Wu et al 2020; Ciencewicki and Jaspers, 2007 review earlier literature). The majority of the pre-existing conditions that increase the risk of death for Covid-19 are in fact the same diseases that are affected by long-term exposure to air pollution (Wu et al 2020). However, the causal claims of existing studies often lack grounding.

This project seeks to identify causal effects of long-term exposure to fine particulate matter on Covid-19 mortality rates using an instrumental variable approach. The availability of high-quality data has proven necessary for informative epidemiological modelling of Covid-19. Likewise, we will seek disaggregated data on the temporal and spatial evolution of the epidemic with the Lombardy Region, covering confirmed cases, mortality and, if possible, hospitalization. Partnerships with epidemiologists will be considered.


  • Ciencewicki, J. & Jaspers, I. (2007) Air pollution and respiratory viral infection Inhalation toxicology, Taylor & Francis, 19, 1135-1146
  • Wu, X.; Nethery, R. C.; Sabath, B. M.; Braun, D. & Dominici, F. (2020) Exposure to air pollution and Covid-19 mortality in the United States. Cold Spring Harbor Laboratory