eklibanerschiff/madagascar-pollution

# Nationwide Assessment of Ambient Particulate Matter in Madagascar Using Low-Cost Sensors and Statistical Modeling **Authors:** Oladimeji Mudele¹,²*, Eleanor Klibaner-Schiff³*, Giacomo De Nicola¹,², Marissa L. Childs⁴, Hervet J. Randriamady¹,⁶, M. Ando Miharifetra⁵,⁶, Joël Rajaobelison⁷, Martin Bbaale⁸, Gideon Lubisia⁸, Joel Ssematimba⁸, Deo Okure⁸, Engineer Bainomugisha⁸, Christopher Golden¹,²,⁶ ¹ Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA ² Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA ³ Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, USA ⁴ Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA ⁵ Departement Production et Partenariat, Institut Malgache des Vaccins Veterinaires (IMVAVET), Ampandrianomby, Antananarivo, Madagascar ⁶ Madagascar Health and Environmental Research (MAHERY), Maroantsetra, Madagascar ⁷ Institut National des Sciences et Techniques Nucl´eaires, Madagascar ⁸ AirQo, Makerere University, Kampala, Uganda * These authors contributed equally as first authors. ## Abstract Ambient air pollution is a major cause of premature mortality in Madagascar, yet routine ground-based monitoring has been absent. We deployed 20 low-cost AirQo sensors across five administrative regions in diverse ecological zones after calibrating the sensors using collocation with reference-grade monitors in Boston and U.S. Embassy in Antananarivo, Madagascar. We found strong temporal agreement (R² values of 0.88 and above) between AirQo sensors and co-located reference monitors that supports their use for population-level exposure assessment. Using hourly data aggregated to daily means, we characterized spatial and temporal patterns of fine (PM2.5) and coarse (PM10) particulate matter, evaluated exceedances of World Health Organization (WHO) air quality guidelines, and fit generalized additive mixed models …