摘要：Air pollution present the greatest threat to human health and welfare in urban environments. Population growth, industrial activities, expanded transport system, vehicular traffic, poor road planning, poor land use and traffic congestion contribute to the problem. Particulate matter (PM2.5 and PM10) has become the principal pollutants due to increased material use, energy demand and use as a result of global economic growth. This study assessed the levels of PM10 in ambient air and heavy metal composition in Nairobi city. Sampling sites were classified into three categories namely; controlled areas, industrial and residential areas as proscribed in the EMCA Air Quality Regulations, 2014. Portable Mini-Vol ambient air samplers were used for fine particulate monitoring. The concentrations of manganese, lead, and cadmium was determined in PM10 samples from all sampling sites. The lead concentration mean was 0.07 ± 0.06 μg/m3, 0.34 ± 0.35 μg/m3 and 1.10 ± 0.59 μg/m3 for residential, controlled and industrial areas respectively. Generally, all afternoons had high particulate matter while the lowest concentration levels of PM10 were recorded at night.
