Urban NO2 Pollution and Health Outcomes: Natural-Experiment Evidence on the Predicted Benefits of the EU Zero-Emission-Vehicles Resolution

In March 2023, the EU approved a zero-emission mobility resolution, which mandates zero CO2 emissions for all new vehicles by 2035. This measure has sparked a heated debate due to its uncertain effectiveness in reducing pollution and CO2 emissions globally. Nevertheless, the shift towards zero-emission vehicles has the potential to decrease local nitrogen dioxide (NO2) pollution, particularly in urban areas where air quality is a major concern for citizens’ health. This study investigates what may be the predicted impact of the EU zero-emission mobility policy on local NO2 levels, using the draconian stay-home provision of the Italian Covid-19 lockdown of early 2020 as a natural experiment which generated an exogenous fossil-fuel-traffic abatement that proxies the implementation of the resolution. We exploit data from the urban areas with elevated traffic density in the Po-river valley in Northern Italy, a region with the highest peaks of air-pollution in Europe, and we develop a novel intertemporal statistical matching approach which is uniquely suited for policy evaluations on air-quality outcomes in the context of multivariate time series data. The results from our causal inference analysis show that Covid-19 lockdown led to a mean NO2 reduction of 13.62 μg/m3 (around 53% from a baseline average level of 25.8 μg/m3). According to medical literature, this decline in NO2 translates into a reduction in the relative risk of total, cardiovascular, and respiratory mortality of about 9%, 8%, and 4%, respectively. Moreover, we find a marked heterogeneity in the estimated impact of lockdown on pollution and health, with greater decreases in NO2 and in the relative risk of mortality observed for higher baseline pollution levels. These findings suggest that the EU 2035 resolution is indeed expected to improve local air quality and citizens’ health in urban areas with high traffic density. The estimated benefits, however, are likely to vary across EU regions based on prevailing local meteorological conditions and urban texture features, which determine a different baseline pollution, supporting the rationale for a spatial differentiation of the EU zero-emission mobility policy.