SOURCE APPORTIONMENT OF URBAN PAHs USING MOLECULAR CLUSTER SIGNATURE

Abstract

This study has been conducted to investigate the source apportionment of Polycyclic Aromatic Hydrocarbons (PAHs) by molecular marker approach. PAHs present in suspended particulate matter (SPM) of urban atmosphere in Nagpur (India). Five urban sites including four outdoor (industrial, traffic, residential and commercial area) and one indoor (laboratory) have been selected for the collection of samples. Monitoring was carried out for Five months, December 2009 to April 2010. Total 150 samples were collected as 30 samples on each location. Sampling was performed using a low volume air sampler equipped with glass micro fiber filter for 24 h. The method used for extracting PAHs utilized procedures like ultrasonication (Seifert and Steinbach, 1977), and the concentration of PAHs was determined using Fluorescence Spectrophotometer. Maximum average concentrations of PAHs have been observed at industrial site and traffic site. The signature of fluorescent molecules have been obtained for each location and these signature were different that identifies their specific source. Source apportionment were carried out using a method having simple and easy to understand is Molecular Cluster Signature (MCS). Application were using PAHs concentration data that make a signature are clustered to a point on a ratio scatter plot that can be described by a single source profile.