The changing role of dust and open fires PM 2.5 on Africa’s air quality and human health

Bibliographic Data

ID15548322
AuthorsAdwoa Aboagye-Okyere (0009-0001-7413-5595, corresponding author), Daphne Meidan (0000-0001-7746-4979, Instituto de Química Física Blas Cabrera, corresponding author), Douglas S Hamilton (0000-0002-8171-5723, North Carolina State University, corresponding author), Peter Hess (0000-0003-2439-3796, corresponding author), Olga Kalashnikova (0000-0002-7578-0430), О В Калашникова (0000-0002-1330-1529, Jet Propulsion Laboratory, corresponding author), M J Garay (0000-0002-1374-5074, corresponding author), Michael Garay, N M Mahowald (0000-0002-2873-997X, corresponding author)
Year2025
Volume20
Issue9
Pages094013-094013
Publication date2025-07-16
Peer ReviewedYes
Open AccessYes
TypeARTICLE
VenueEnvironmental Research Letters (JOURNAL)
Journal identifiersISSN: 1748-9326 • E-ISSN: 1748-9326
PublisherIOP Publishing (PUBLISHER • GB)
DOI10.1088/1748-9326/adf07e
OpenAlexW4413095261
LanguageEN
References cited84

Aerosol pollution events pose serious threats to humans and ecosystems. Natural aerosols are much less studied than fossil fuel-sourced aerosols for their air quality impacts, even though ‘natural’ aerosols such as dust and wildfires are likely to have substantially changed because of anthropogenic activities. Using the Community Earth System Model version 2 and the Community Atmospheric Model version 6 atmospheric model, we simulated dust and open-fire PM 2.5 concentrations over Africa for preindustrial (PI), present-day, and future scenarios. Health impacts were assessed using the integrated exposure–response model applied to gridded population and disease-specific mortality data. Currently, we estimate that desert dust causes 30 000 (95% confidence interval (CI) 29 700–303 000) excess deaths annually in Africa (36% of the total excess premature mortality), while open fires result in 20 000 (95% CI: 19 500–22 500) excess deaths (24% of the mortality). All mortality estimates reported in this study represent annual excess deaths, calculated based on annual average PM 2.5 concentrations. Concentrations of dust dominate aerosol concentration at the continental scale, and paleo records suggest dust loading has increased by 55% since PI times. Because of the lower population in dust-dominated regions, these do not affect health as much as combustion but are still important. In PI times, we estimate deaths due to dust as 6400 (95% CI: 6050–6750) (or 7000 if we keep the population at current levels), showing a large growth to the present day (over 400% increase). Excess deaths due to open fires have increased from 6900 (95% CI: 5800–7400) in the PI to 20 000 today (approximately 190% increase). For future scenarios in 2100, there is significant uncertainty; therefore, we present a high and low scenario, indicating that in the future, between 53 000 (95% CI: 49 000–55 000) and 67 000 (95% CI: 63 000–70 000) deaths will result from dust. Similarly, for future open fire excess deaths, we estimate a range of 19 000–40 000 (95% CI: 33 000–44 000) deaths, including population changes (−1% to +100% changes relative to today). In the current climate, as well as in the past and future, the amount and proportion of deaths attributed to ‘natural’ aerosols exceeds 50% of the total PM 2.5 attributable mortality in Africa, showing that addressing possible changes in ‘natural’ aerosols is extremely important for improving air quality

Aerosol · Air pollution · Air quality index · Atmospheric sciences · Biology · Climatology · Environmental health · Geography · Meteorology · Mineral dust · Population · Air Quality and Health Impacts · Atmospheric aerosols and clouds · Atmospheric chemistry and aerosols · Environmental Science · Medicine · Ecology · Geology

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