Exposure to indoor and outdoor air pollution in schools in Africa: Current status, knowledge gaps, and a call to action

Chronic exposure to indoor and outdoor air pollution is linked to adverse human health impacts worldwide, and in children, these include increased respiratory symptoms, reduced cognitive and academic performance, and absences from school. African children are exposed to high levels of air pollution from aging diesel and gasoline second-hand vehicles, dusty roads, trash burning, and solid-fuel combustion for cooking. There is a need for more empirical evidence on the impact of air pollutants on schoolchildren in most countries of Africa. Therefore, we conducted a scoping review on schoolchildren's exposure to indoor and outdoor PM(2.5) (particulate matter with an aerodynamic diameter less than 2.5 μm and PM(10) (particulate matter with an aerodynamic diameter less than 10 μm) in Africa. Following PRISMA guidelines, our search strategy yielded 2975 records, of which eight peer-reviewed articles met our selection criteria and were considered in the final analysis. We also analyzed satellite data on PM(2.5) and PM(10) levels in five African regions from 1990 to 2019 and compared schoolchildren's exposure to PM(2.5) and PM(10) levels in Africa with available data from the rest of the world. The findings showed that schoolchildren in Africa are frequently exposed to PM(2.5) and PM(10) levels exceeding the recommended World Health Organization air quality guidelines. We conclude with a list of recommendations and strategies to reduce air pollution exposure in African schools. Education can help to produce citizens who are literate in environmental science and policy. More air quality measurements in schools and intervention studies are needed to protect schoolchildren's health and reduce exposure to air pollution in classrooms across Africa.