Mortality attributable to ambient PM2.5 pollution in China's aging population

Abstract

Background

As China's population is aging rapidly, understanding the shifts in PM_2.5 attributable mortality within this context is crucial for informing future clean air policies.

Methods

We adopted a Fusion relative risk model, combined with 100 m resolution age structure data, to better estimate China's age- and cause-specific mortality attributable to PM_2.5 over 2010–2019, and projected attributable mortality in 2030 and 2060 at a 0.1° spatial resolution under three scenarios: Baseline, Carbon-peak and Carbon-neutral. We also assessed the impact of population aging using a decomposition method at the grid level.

Results

PM_2.5 attributable deaths declined by 9.2 % from 2010 (1.95 million, 95 % UI: 1.80–2.09) to 2019 (1.77 million, 95 % UI: 1.64–1.90), with population aging contributing an increase of 0.48 million deaths. The elderly population constituted over 70 % of total attributable mortality during 2010–2019, and this share is expected to increase to over 90 % in 2060 under three future scenarios. Under Baseline scenario, attributable deaths are expected to increase, with population aging as the major contributor. Under Carbon-peak scenario, the projected mortality declines over 2019–2030 and 2030–2060 will be partly offset by population aging. Under Carbon-neutral scenario, population aging is projected to increase attributable deaths by 0.57 million and 1.27 million over the two periods, largely offsetting the reductions achieved by the declines in PM_2.5 concentrations and cause-specific baseline mortality rates.

Conclusions

Population aging is the main factor that increases PM_2.5 attributable mortality. Specific measures considering the vulnerability of the elderly are needed to further alleviate future health burden from air pollution.