Assessing the short-term exposure risk and mortality burden of dust and fine aerosol PM2.5 in Central Asia.

Central Asia faces severe exposure risks to fine particulate matter (PM2.5) from both wind-blown dust and anthropogenic emissions; however, the associated health effects remain poorly understood. This study assesses the short-term PM2.5 exposure risk and associated premature mortality burden across Central Asia. The highest seasonal mean PM2.5 concentration (13.4 μg m) occurs in winter, dominated by anthropogenic fine aerosols, followed by spring (12.2 μg m), dominated by dust emission. Population-weighted PM2.5 concentrations exhibit widespread declines from 2017 to 2022, with the largest decrease observed in Almaty. In 2022, the number of days with population-weighted PM2.5 exceeding the WHO air quality guideline ranged from 124 days in Kazakhstan to 251 days in Tajikistan. Among major cities, Almaty experiences the highest exposure to unhealthy and hazardous PM2.5 levels. Short-term PM2.5 exposure is estimated to cause 5074 (95% CI: 3428-6728) premature deaths annually in Central Asia, including 2225 (1504-2949) in Uzbekistan, 1448 (978-1922) in Kazakhstan, 546 (369-724) in Tajikistan, 437 (295-579) in Turkmenistan, and 418 (282-554) in Kyrgyzstan. Source attribution using MERRA2 aerosol reanalysis indicates that dust contributes 63-90% of the mortality burden, although these estimates are subject to uncertainties in the representation of dust and anthropogenic sources in the underlying models.