Correlation between atmospheric pollution and contagion intensity in Italy and Lombardy

Analysis of air pollution levels aims to verify potential correlations between the territorial spread of major atmospheric pollutants, fine dust and nitrogen dioxide and the severity of territorial Covid-19 contagion. A diachronic reading of pollution levels also makes it possible to correlate the impact of restriction measures for combating the SARS-CoV-2 epidemic with data on atmospheric pollution. It needs to be stressed from the start that any estimate of potential correlations should never be taken as final or absolute: atmospheric pollutants do present variations in dispersion and intensity that depend on atmospheric conditions. These considerably affect pollutant accumulation or dispersion, and consequently also monitoring-station measurements. In fact, data reliability increases whenever the reference timeframe is extended, as in the case of monthly or annual averages. Nonetheless, in atmospheric pollution analysis, space is as important as time, for at least two reasons: (i) analyses conducted in the Lombardy region rely on an IT model that returns approximate information from the data acquired via the network of survey-monitoring stations; (ii) data are mapped with reference to municipal administrative units. In mountain areas, data record a sharp difference in air condition between the urbanized valley bottoms and the sparsely settled area of the medium-high sections on mountain slopes. It follows that the maps are more reliable in detecting the atmospheric conditions of fields and extended territorial areas, rather than individual areas on a municipal basis.