LEVELS AND PROFILES OF POLYCYCLIC AROMATIC HYDROCARBONS AND POLYCHLORINATED BIPHENYLS IN SOIL AT AN INDUSTRIAL AREA IN DAR ES SALAAM, TANZANIA

This study investigated the levels and profiles of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in soil from an urban/industrial area in Dar es Salaam, Tanzania. Analysis was performed using a high resolution gas chromatograph coupled to a high resolution mass spectrometer (GC?MS). The results indicated that the contents of total PAHs (16 US EPA priority PAHs) ranged from 104 ng/g to 35890 ng/g and the pollution level is classified as a moderate level with some spots of high and very high pollution levels. The composition profiles of PAHs were dominated by high molecular weight (4-6 rings) PAHs. The ratios of phenanthrene/anthracene and fluoranthene/pyrene indicated that the concentrations of PAHs in the area were influenced by pyrogenic (combustion) sources and petrogenic (petroleum) sources. The total concentrations of 18 PCBs in soil varied from 0.4 ng/g to 282 ng/g. Most of the PCBs concentrations were generally low. PCB 138, PCB 153, PCB 180, PCB 101 and PCB 118 accounted largely among the contaminants of PCBs.