ABSTRACT
Using spatially- and temporally-resolved data from the New York City Community Air Survey (NYCCAS) and the New York State (NYS) Department of Environmental Conservation (DEC) network, we characterized changes in fine particulate matter (PM2.5) and nitrogen dioxide (NO2) following the COVID-19 shutdown in NYC (3/20/20 – 6/7/20). Difference-in-difference analysis of PM2.5 and NO2 measured at 93 sites were used to estimate the change in citywide pollution attributable to the shutdown. We also quantified how these pollutant changes varied among different demographic groups using difference-in-difference analyses stratified by neighborhood poverty levels and rates of PM2.5-attributable health outcomes. Spatial patterns of PM2.5 and NO2 were interpolated across NYC by fitting land-use regression models to measurements at the 93 sites. Weather conditions and emission source trends were analyzed to determine the potential effects of meteorology and specific emission sources on the observed pollution changes. We estimate that citywide average PM2.5 and NO2 decreased by approximately 25% and 29%, respectively, due to the shutdown. Weather readings show little evidence that meteorology biased our results in the direction of our findings. Data on major sources of PM2.5 and NO2 pollution suggests that decreased vehicle traffic and commercial cooking contributed to declines in air pollution during this period. Pollution reductions occurred disproportionately in the city's central business district (CBD), with smaller changes in other areas of the city, such as those with the highest burden of air pollution-related health impacts. These findings emphasize the need to target pollution sources in communities that suffer the greatest from pollution exposure in the design of equitable environmental health policy. © 2022