Validity analysis of Air Quality Health Index in six cities of Jiangsu Province, China

Objective To construct an Air Quality Health Index (AQHI) using the method developed by National Institute of Environmental Health, Chinese Center for Disease Control and Prevention for Changzhou, Huai'an, Nanjing, Taizhou, Wuxi, and Yangzhou of Jiangsu Province, China, and to verify its consistency with Air Quality Index(AQI) and health risk prediction ability.

Methods A region-specific AQHI was constructed for each city using the exposure-response coefficients of PM_2.5, O₃, NO₂, and SO₂ with total deaths in China reported in the literature, the daily average number of deaths in each city, and the daily average mass concentrations of the four pollutants in each city in 2015—2017. The distribution characteristics of AQHI risk levels in the six cities were analyzed, and the ability of AQHI and AQI to indicate different health outcomes was compared.

Results The cumulative proportions of low and medium AQHI risk levels in the six cities all exceeded 90%. The AQHI levels increased with increase in the AQI levels of the six cities, and the result were not mutually exclusive, with a consistent overall trend. Each increase in the risk level was associated with a higher percentage increase in AQHI risks compareid with AQI risks for each of the five causes of death outcomes (total non-accidental mortality, cardiovascular mortality, stroke mortality, respiratory mortality, and chronic obstructive pulmonary mortality) in the all six cities. Sensitivity analysis showed that the model is basically robust.

Conclusion AQHI has a higher ability to indicate health risks than AQI.