Mortality benefits of vigorous air quality improvement interventions during the periods of APEC Blue and Parade Blue in Beijing, China

Vigorous air pollution control measures were implemented during the 2014 Asia-Pacific Economic Cooperation and a large-scale military parade (described here as “APEC Blue” and “Parade Blue” periods) in Beijing, China. A natural experiment was conducted in a health impact assessment framework to estimate the number of deaths attributable to PM_2.5, using concentration-response functions derived from previous studies conducted in Beijing, combined with the differences in PM_2.5 concentrations between intervention and reference periods. Substantial reductions in daily PM_2.5 concentrations were observed during both intervention periods. Using the same dates from the prior year as a reference, daily PM_2.5 concentration decreased from 98.57 μg/m³ to 47.53 μg/m³ during “APEC Blue”, and from 59.15 μg/m³ to 17.07 μg/m³ during the “Parade Blue”. We estimated that 39–63 all-cause deaths (21–51 cardiovascular, 6–13 respiratory deaths) have been prevented during the APEC period; and 41–65 deaths (22–52 cardiovascular, 6–13 respiratory deaths) have been prevented during the Parade period. This study shows that substantial mortality reductions could be achieved by implementing stringent air pollution mitigation measures.