Abstract: Air quality in Setapak district of Kuala Lumpur was
studied by analysing the rainwater chemical composition using ion
chromatography method. Twelve sampling sites were selected and
120 rainwater samples were collected in the period of 10 weeks. The
results of this study were compared to the earlier published data and
the evaluation showed that the NO3
- ion concentration increased from
0.41 to 3.32 ppm, while SO4
2- ion concentration increased from 0.39
to 3.26 ppm over the past two decades that is mostly due to rapid
urban development of the city. However, it was found that the
chemical composition for both residential and industrial areas does
not have significant difference. Most of the rainwater samples
showed alkaline pH (pH > 5.6). The possible factors for such alkaline
pH in rainwater samples are assumed to be the marine sources,
biomass burning and alkaline character of soil particles.