Assessment and Measurement of Atmospheric Pollution (Particulate Matter) Around Zawiya City-Libya

Abstract

Total air suspended particulates (TSP) samples were collected over glass fiber filter and determined gravimetrically. The contents on the glass filter was digested in HF-HCl-HNO3 mixture and the trace elemental analysis of Al, Fe, Mn, and Pb were performed using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) technique, which offers many advantages such as low detection limits, wide linear calibration range and no matrix interference in addition to simultaneous multi-element determination. The filter with TSP was weighted, dissolved in HF-HCl-HNO3 acid mixture and the trace element such as Al, Fe, Mn and Pb were determined using (ICP-OES) technique. This work was carried out at four sites around Zawia city. Three sampling location were selected on sites of heavy traffics and industrial activities. These sites were (A1) at the center of Zawia city; (A2) near the power station and the refinery; (A3) nearby the main coastal road and (A4 control) at zone where there are no industrial activities or any obvious source of pollution. These samples were collected during Summer, Autumn, Spring, and Winter. The daily variation of TSP during this period showed the lowest value 70 µg/m3 in January (Winter), and the highest value 587.121 µg/m3. This value is relatively high compared with EU limit values (300 µg/m3), USEPA (150 µg/m3), and WHO (150-230 µg/ m3). The mean monthly variation of TSP showed the lowest measured result of 78.28 ± 0.08 µg/m3 in January and the highest value 306 µg/m3 in May. Seasonal variation of TSP showed high results during Spring season which is 239.44 µg/m3 and all other seasons showed lower values of 131.19 µg/m3, 198.28 µg/m3 and 159.85 µg/m3 for Winter, Autumn, and Summer, respectively compared with Spring season. The trace elements levels in TSP were Al>Fe>Pb>Mn. The concentration of Al, Fe, Mn and Pb are lower in site A4 and Al and higher in sites A3 and A2 due to heavy traffic and industrial activities. The meteorological parameters over the study area showed some factors such as wind speed, humidity and temperature that may affect TSP concentrations.