Application of positive matrix factorization to identify potential sources of PAHs in soil of Dalian, China

Authors:Degao Wang a,*, FulinTianb, Meng Yang a, Chenlin Liu a, Yi-Fan Li a,c,**
aInternational Joint Research Center for Persistent Toxic Substances, Dalian Maritime University, Dalian 116026, China
bLiaoning Academy of Analytic Science, Shenyang, PR China
cScience and Technology Branch, Environment Canada, Toronto, Canada
Summary
Polycyclic aromatic hydrocarbons (PAHs) are widespread contaminants which are composed of benzene fused together. Positive matrix factorization is a receptor modeling technique which is being used for source apportionment of pollutant sources.
Data consisted of 17 samples in summer and 14 samples in winter collected from Dalian China.19 different PAHs out of 25 identified PAHs were selected from 3 different sources viz., coal-fired boilers, diesel engines, and gasoline engines. Names and concentrations of selected PAHs from the selected sources are given in table 1.
 
Positive matrix factorization defines a concentration matrix containing concentration of chemical species at sites selected for sample collection as the product of source composition and contribution factor matrices with a residue matrix.
In summer, factor 1 was found to contribute 46% of total PAHs. It was identified as coal source profile. Factor 2 had 30% contribution of total PAHs. The source of these PAHs was from the emissions of diesel engines. Factor 3 showed 24% of total PAHs which was being imparted from gasoline engines.
In winter, factor 1 showed 72% contribution of total PAHs, the profile was found to be the same as from coal-fired boilers. Factor 2 showed 20% contribution in total PAHs contaminating the atmosphere with average emission of both diesel and gasoline engines as the identified source. Factor 3 contributed only 8% of total PAHs with gasoline engine enriched profiles.
Fractional source composition of all selected PAHs in all the factors in both seasons is shown in figure 1.
 
Figure 2

Reviewer: Aamir Alaud-din
        aamiralauddin@gist.ac.kr