TITLE:
Characterization of Atmospheric Organic Carbon and Element Carbon of PM2.5 during the Long Dry Period in Cotonou, Benin
AUTHORS:
Julien Djossou, Kalil Pierre Mathos, Simon Pierre Lamah, Faya Maurice Yombouno, Nakany Camara, Alpha Madiou Diallo, Mamadouba Aboubacar Fofana, Aboubacar Diallo
KEYWORDS:
Aerosol, PM2.5, Concentration, Carbonaceous, Organic, Elemental Carbon
JOURNAL NAME:
Open Journal of Air Pollution,
Vol.14 No.1,
March
10,
2025
ABSTRACT: In the African countries, air pollution appears as a public health problem. The health consequences of this pollution are currently causing concern among the population and decision-makers. Air quality degradation is a major issue in the large conurbations on the shore of the Gulf of Guinea. In this study, daily atmospheric PM2.5 and carbonaceous aerosol (organic carbon (OC) and elemental carbon (EC)) concentrations were measured at Dantokpa site in Cotonou, Benin, Southern West Africa during the long dry period (December 2016 to March 2017). We analyzed the mass concentrations and carbonaceous species of PM2.5. The average PM2.5 concentration was 69.20 µg·m−3, while OC and EC concentrations were 34.39 ± 12.62 μg·m−3 and 10.82 ± 7.89 μg·m−3, respectively. Total carbon (TC) accounted for 65.35% of the PM2.5. Strong correlation between OC and EC was found during the long dry period, suggesting the contributions of similar sources. We have also studied the correlations between OC-EC and PM2.5. We found that OC was highly correlated with PM2.5 (R = 0.94) while EC was moderately correlated with PM2.5 (R = 0.77), suggesting that carbonaceous aerosols and PM2.5 shared major sources at Dantokpa site during the long dry seasons.