Determination of sulphur dioxide concentrations in ambient air of some selected traffic areas in kaduna metropolis

Abstract

This research study was aimed at determining concentrations of sulphurdioxide in ambient air of some selected areas viz: industrial area (Kakuri), high vehicler traffic/commercial area (Leventis Roundabout), traveling route (Kawo overhead bridge), Low vehicler traffic area (Tafawa Balewa Roundabout), residential area (Kawo New Extension) and a control site (NFA base) in Kaduna metropolis Nigeria. Air sample was collected at each sampling site by passing ambient air through an impinger bottle containing hydrogen peroxide (absorbent), at a flow-rate of 10 L/min for 30 min using air vacuum pump. The concentration of SO2 in the resultant solution (absorbent) was determined by titrating against 0.005 moL/dm3 NaOH solutions. The average SO2 concentrations in the six sampling stations were within the range 0.16-0.75 ppm, with the highest values of 0.75 and 0.70 ppm at highly industrialized area (Kakuri) and a high traffic area (Leventis roundabout) respectively. The ambient air concentrations of SO2 depict the pattern; Industrial area (Kakuri) >High vehicler traffic/commercial area (Leventis roundabout) >Traveling route (Kawo overhead bridge) >Low traffic area (Tafawa Balewa roundabout) >Residential area (Kawo New Extension) >Remote area (NAF Base Mando). Except for highly industrial area (Kakuri) and the high traffic area (Leventis), The ambient air SO2 concentration are within the acceptable limits of United States Environmental Protection Agency (EPA) and Nigeria's Federal Environmental Protection Agency (FEPA) standard limit which is 0.5 ppm for 30 min exposure time. © Maxwell Scientific Organization, 2013.