Advancement in the Monitoring Techniques of Particulate Matter and Nitrogen Oxides in African States: A Systematic Review with Meta-Analysis

Abstract

Air quality monitoring is fundamental to mitigating the impacts of air pollution on human health and the environment. This ensures that air quality management is effective and that the potential negative effects on the environment and human health associated with poor air quality are understood and mitigated. Despite this, Africa continues to struggle with a lack of sufficient air pollution exposure data that can influence the understanding of air pollution status. The purpose of this research is to look at the progress made by African countries in developing monitoring techniques for pollutants such as particulate matter and nitrogen oxides in urban settings. The study conducted meta-analyses of studies that looked at technological advancements in monitoring PM and NOx exposure levels on the African continent. Every country in the African continent that has monitored both PM and NOx ambient pollutants was included in the review. Furthermore, in an attempt to include the most recent studies that monitored PM and NOx only ambient air quality studies published between 2010 to 2022 were eligible for inclusion in the current study. From eligible studies, authors, publication year, exposure characterization method, study setting, pollutants and technique used were extracted. Microsoft Excel 2019 was used for data analysis. To this end, the data was presented using graphs and numerical techniques. The results of this study show that 67% of African countries use fixed monitoring systems, which has a serious limitation. Whilst, on the other hand only 10% of the countries, geographically located within North Africa (Tunisia, and Algeria), and Southern Africa (South Africa) regions used the mixed monitoring techniques, such as active sampling and remote sensing. In conclusion, most African regions rarely conduct air quality exposure assessments that incorporate air quality modelling techniques.