Lithometeors and public health issue in the city of Maroua (Far North Cameroon)

Abstract The Far North region of Cameroon is subject to significant dust storm aerosol concentration, leading to deterioration in urban air quality. The temporal monitoring of aerosols and the assessment of their impacts on human health were carried out in the city of Maroua, through a field campaign resulting in the collection of in situ dust aerosols data and those relating to epidemiology obtained from the Maroua Regional Hospital. Four aerosol samples were also submitted to Laboratory chemical analysis. The results of the present study have shown first of all that there are strong correlations between the temporal evolution of aerosol episodes and the prevalence of respiratory diseases. The period from January to march is positioned as the high-risk pollution period. Chemical analysis of the aerosols revealed the presence of potentially toxic elements such as threshold pollutants (Lead, Cadmium, and Cyanide) and non-threshold pollutants (Potassium, Sodium, Sulfate and chloride). The concentrations of the chemical elements were observed in the following order: SO42- > K+ > Na+ > Ca2+ > Cl- > Mg2+ > NH4+ > NO3- > F- > Pb > Cd > CN-; the presence of PO43- and As not having been detected. The exposure of the human population to these potentially toxic elements from inhalation pathway suggested an acceptable non-carcinogenic risk and a very low carcinogenic risk.