Determination of benzene, toluene and xylene in ambient air inside three major steel plant airsheds and surrounding residential areas

Concentration of benzene, toluene and xylene were measured in three steel plants and the nearby residential areas. A simple packed column Gas Chromatograph was used for analysis and samples were collected using fabricated activated carbon traps. The study was carried out over a two year period of 4 to five months. Mean concentration of benzene mu g/m(3) inside the three plants were found to be 717 mu g/m(3), 918 mu g/m(3) and 576 mu g/m(3). For toluene the concentrations were 183 mu g/m(3), 258 mu g/m(3) and 198 mu g/m(3) and for xylene they were 6 mu g/m(3), 124 mu g/m(3) and 32 mu g/m(3) respectively. Concentration of benzene in the nearby residential areas were 228 mu g/m(3), 783 mu g/m(3) and 552 mu g/m(3). For toluene they were 160 mg/m(3), 412 mg/m(3) and 155 mg/m(3) and for xylene thay were 9 mu g/m(3), 265 mu g/m(3) and 33 mu g/m(3) respectively. The compositional pattern was found to be very different from that found in other studies. The projected lifetime cancer risk from exposure to atmospheric benzene has been estimated to vary from 2.92 per 1000 to 5.92 per 1000 for plant workers and 1.62 per 1000 to 4.02 per 1000 respectively for the people living in the nearby residential areas.