Potentially Toxic Elements in Urban Dust of Jining City, China: Pollution Characteristics and Source Identification

In Jining, 306 gridded sited urban dust samples were collected from residential, educational and park area on windowsills or building platforms 1.5 to 2 m above the ground, as well as 24 typical pollution endmember dust samples involving traffic dust, construction dust, coal combustion dust, and vehicle exhaust dust. The content, spatial distribution, source, and contamination factor of indicators in dust samples were studied. Among typical pollution endmember dust samples, most indicators, such as As, Cd, Co, Cu, F, Ni, Pb, S, and Se, were found in the highest concentrations in coal combustion dust, while construction dust had the lowest. In urban dust samples, Hg and Se contamination factors were 3.06 and 2.05, respectively, whereas, As, Cd, Cr, F, Ni, Pb, Zn and CaO contamination factors were approximated or less than 1.0, and the contamination factor decreasing order was Hg > Se > Pb > Zn > Cr > Cd > Ni > As > F > CaO. PTEs in urban dust samples were found in high concentrations in highly populated areas, heavily trafficked locations, and plant environs. Four major sources in urban dust were discriminated referencing to the results of factor analysis, correlation analysis, PCA-MLR, indicator combination feature and the spatial distribution of indicators, viz. As, Cr, Ni and F primarily derived from natural source; Cd, Pb and Zn mainly originated from traffic source; Se and Hg were mainly from coal combustion source; and CaO were mainly from construction source, which respectively contributed 32.1, 31.0, 22.3 and 14.6% to the total content of 10 indicators determined in urban dust.