Global Health Benefits of Cleaner Air
Cleaner air, longer lives: Quantifying how air pollution impacts life expectancy
We develop the first systematic estimates of how air pollution shortens life expectancy around the world, taking advantage of a consistent global dataset. The impact of air pollution on human life spans around the world is strikingly large.
Citation: Apte JS, Brauer M, Cohen AJ, Ezzati M, Pope CA III. 2018. Ambient PM2.5 reduces global and regional life expectancy. Environmental Science & Technology Letters 5, 546-551. Named "Best paper of 2018" by ES&T Letters.
Many developing countries face two simultaneous risks from air pollution: on one hand, the outdoor air pollution often associated with industrialization and economic development, and on the other hand, high levels of indoor air pollution from cooking and heating with solid fuels like wood. The combined effect of indoor and outdoor air pollution on life expectancy is very large in places like India, Pakistan, and Bangladesh, where the average life is shortened by more than 2.5 years from the combined result of indoor and outdoor air pollution. In Sub-Saharan Africa, household air pollution has a larger impact on life expectancy than does outdoor air pollution.
Ambient fine particulate matter (PM2.5) is one of the largest global risk factor for premature mortality, resulting in 3.2 million annual deaths in year-2010. To characterize how improvements in ambient PM air quality could result in improved health worldwide, we develop a high-resolution (10-km) model using data and methods from the 2010 Global Burden of Disease (GBD) study. The model combines fine-scale estimates of ambient PM concentrations with regional-cause specific mortality datasets and non-linear integrated exposure-response functions that describe the relationship between PM2.5 and mortality risks.
Improving outdoor air quality — in clean places and in polluted places alike — could potentially avoid millions of worldwide deaths each year. Meeting the WHO PM2.5 air quality guideline concentration of 10 µg m-3 globaly could avoid up to 2.1 million annual deaths. One striking finding of this work is that comparatively small improvements in PM in already-clean locations (e.g, reductions of 1-4 µg per cubic meter in the U.S. and Europe) could avoid hundreds of thousands of annual deaths, while achieving comparable benefits in polluted developing countries (e.g., China, India) would require much larger improvements in air quality. However, the potential health benefits of fully meeting WHO guidelines in China and India would be very large, avoiding roughly 1.4 million premature annual deaths from PM.