Chemical and Morphological Characteristics of Particulate Matter Suspended in the Air of the Dhaka University Area of Bangladesh

Total suspended particulate matter (SPM) in the urban atmosphere of Dhaka city was collected using a high volume sampling technique for a period of one month (August 2017-September 2017). Chemical characterization of particulate matter (PM) was investigated, and characterized concerning the size distribution, morphological features such as count, total area, average size, perimeter, circularity, aspect ratio (AR), roundness; equivalent spherical diameter (ESD), surface area and volume of PM. The results of elemental analysis showed that the presence of heavy metal in PM was ten to hundred times higher than the standard value prescribed by WHO and USEPA. Several morphological analysis indicated that particles varying in shape from nearly spherical to various irregular shape, had higher surface energy, higher content of Cl and S bearing particles and had a large surface area which can cause greater damage to lungs. The presence of various organic compounds containing functional groups like alcohols, ketones aldehydes, carboxylic acids as well as unsaturated and saturated carbon bonds was observed by FT-IR analysis. Scanning Electron Microscopy (SEM) was used to characterize the morphology of the PM. Agglomerates and shoots type particles were mostly seen in SPM.