The study of VOCs (volatile organic compounds) in ambient air is a field of increasing interest because of the impact they
have on the global environment. Air pollution by VOCs is based on the principles of dilution, diffusion and dispersion. The air
samples were collected by passive sampler (ORSA 5). The air samplers were exposed to a height of 1.5-2.0 m and sampling was
carried out four times a month for a period of 12 months. The adsorbed VOCs were desorbed with carbondisulphide (CS2) and the
solution was analysed using Gc (Gas Chromatography) fitted with FID (Flame Ionization Detector). The results from analysis of the
air samples collected showed that 30 VOCs were captured in the Ketu-Mile 12 area. The VOCs were classified thus: aromatics 37%,
halogenated 38%, esters 2%, ketones 11%, alcohols 4%, ethers 4%, dienes 2%, nitriles 2%. There is a significant difference (Pvalue <
0.05) between the levels of VOCs in Ketu-Mile 12 area. The meteorological parameters showed significant correlations with the
ambient concentrations of VOCs. The monthly mean concentrations of the atmosphere TVOCs (total volatile organic compounds) in
the urban area exhibited a statistical significant difference. Source identification studies showed that seven VOCs chlorobenzene
37.3%, ethanol 18.17%, 2,2-dichloropropane 12.94%, trichloroethane 9.08%, 2-hexanone 7.36%, n-butylbenzene 6.72% and
bromoform 4.90% were the major contributors to ambient air pollution in Ketu-Mile 12 area. The principal component analysis
revealed that the major sources of VOCs in Ketu-Mile 12 areas are mainly anthropogenic and six factors were identified as sources of
VOCs in the studied area with emissions from waste dump dominating.