Investigating the Potential of a Combined Air Quality-heat Index in Predicting Mortality

Abstract

Although the development of the Air Quality Index (AQI) has been significant in informing and protecting the public, it may not be entirely reflective of the health effects from exposure to air pollutants. Meteorological factors that are considered in the heat index (HI), temperature and relative humidity, are not considered when calculating the AQI. It may be important to consider certain meteorological factors when assessing the quality of the air because such factors affect the dynamics of air movement as well as the formation of certain pollutants.Through a series of Quasi-Poisson regression models, we investigated whether the relationship between the AQI and mortality could be strengthened by considering elements of the HI. We found that models that included some form of temperature and relative humidity as explanatory variables exhibited stronger associations to mortality than models that only considered the AQI. These results further support our hypothesis that including elements of the HI when assessing the quality of the air may improve the AQI’s skill in predicting mortality. Our analyses revealed that a combined air quality-heat index may have merit; by including the meteorological elements of the heat index in assessing air quality, the relationship between air quality and mortality was strengthened in some cases.