Field comparison of two Total Suspended Particulates (TSP) samplers to assess spatial variation

Abstract

In 2004, through the assistance of the World Bank, air quality monitoring equipment was supplied from the United Kingdom and United States to Edo State Ministry of Environment in Nigeria. Amongst the air pollution assessment tools supplied, are a portable SKC 506673 high volume Gravimetric Sampler and a light‐scattering method – Haz–Dust™ 10 µm particulate monitor – for airborne particles. In this preliminary study, the two samplers were co‐located at different monitoring sites in Benin City to assess spatial distribution of airborne particles and also to ascertain the collection efficiencies of these monitoring tools. Preliminary results available indicate the non‐compliance of the TSP (Total Suspended Particulates) load obtained at the created monitoring sites with the regulatory limits of 150–230 µgm−3 and 250 µgm−3 set by WHO (World Health Organization) and FMENV (Federal Ministry of Environment) respectively. Differences in the collection efficiencies of these samplers were observed with a coefficient of determination (R2) value of 0.6289 obtained. The principal component analysis (PCA) showed different degrees of correlation between the monitoring sites. Two principal components were identified for the particulate matter distribution by the combined methods, which were further confirmed by the hierarchical cluster analysis. Vehicular exhaust, industrial emissions, combustion of solid wastes, dusts from roads and harmattan dust were identified as the major particulate matter sources at these market environments.