. 2023 May 11;131(5):057004. doi: 10.1289/EHP11882

Table 5.

Deaths attributable to $particulate matter begin subscript 10 end subscript$ and ${NO}_{2}$ concentrations above predefined thresholds^a: results from both single-pollutant and two-pollutant models. Each cell reports attributable cases and 95% CI. Italy, 20 February 2020–15 June 2021 ( $lowercase italic n equals 3995202$ COVID-19 cases, $lowercase italic n equals 124346$ deaths).

$particulate matter begin subscript 10 end subscript$ thresholds	${NO}_{2}$ thresholds				Single pollutant $particulate matter begin subscript 10 end subscript$ : Deaths
	10: Deaths (95% CI)	20: Deaths (95% CI)	30: Deaths (95% CI)	40: Deaths (95% CI)
15	7,430 (326; 14,008)	1,404 ( $negative 3297$ ; 5,798)	$negative 51$ ( $negative 1787$ ; 1,573)	$negative 195$ ( $negative 759$ , 331)	4,582 (2,512; 6,607)
20	8,588 (3,324; 13,512)	2,513 ( $negative 908$ ; 5,749)	370 ( $negative 898$ ; 1,570)	$negative 78$ ( $negative 512$ ; 333)	2,699 (1,476; 3,903)
25	7,303 (3,999; 10,410)	3,021 (858; 5,084)	730 ( $negative 110$ ; 1,534)	38 ( $negative 271$ ; 335)	1,267 (691; 1,837)
30	4,878 (3,176; 6,484)	2,494 (1,401; 3,541)	838 (373; 1,287)	152 ( $negative 38$ ; 336)	393 (214, 571)
35	1,073 (555; 1,544)	683 (250; 1,083)	338 (40; 618)	46 ( $negative 153$ ; 236)	231 (126; 333)
40	0 (0, 0)	0 (0, 0)	0 (0, 0)	0 (0, 0)	0 (0, 0)
Single pollutant ${NO}_{2}$	10,155 (8,295; 11,973)	4,187 (3,410; 4,951)	1,136 (924; 1,346)	239 (194, 285)	—

Note: Results of main model 6, adjusted for interactions between year and month, province, age classes, sex and ventiles of the generalized propensity score. —, no data; AQG, airquality guidelines; CI, confidence interval; ${NO}_{2}$ , nitrogen dioxide; $particulate matter begin subscript 2.5 end subscript$ , particulate matter with aerodynamic diameter $less than or equal to 2.5$ micrometers; $particulate matter begin subscript 10 end subscript$ , particulate matter with aerodynamic diameter $less than or equal to 10$ micrometers; WHO, World Health Organization.

^{^a}

WHO 2021 AQG levels: $15 micrograms per meter cubed$ for $particulate matter begin subscript 10 end subscript$ , $10 micrograms per meter cubed$ for ${NO}_{2}$ ; WHO 2005 AQG levels: $20 micrograms per meter cubed$ for $particulate matter begin subscript 10 end subscript$ , $40 micrograms per meter cubed$ for ${NO}_{2}$ ; EU (European Union) air quality standards: $40 micrograms per meter cubed$ for $particulate matter begin subscript 10 end subscript$ , $40 micrograms per meter cubed$ for ${NO}_{2}$ .