Source Apportionment of Aerosol Lead in Beijing Using Absolute Principal Component Analysis

From 18 September 2005 to 13 September 2006 in Beijing,166 TSP samples were collected at three sites in southern suburb,downtown and northern suburb,respectively.Lead and other 28 elements were determined for those samples by ICP-AES and ICP-MS methods.The lead average concentration of one year in southern suburb,downtown and northern suburb was 179,142 and 102(ng·m~(-3)),respectively.Source identification and apportionment were carried out using absolute principal component analysis(APCA)method.Five groups of sources were recognized.The sources are nonferrous metallurgy(55.6%),coal combustion(16.9%),construction dust(11.8%)and soil dust(10.2%),respectively.Major sources of aerosol lead in Beijing were from nonferrous metallurgy industry.Lead associated with coal combustion and other sources were evenly distributed over three sites.However,industrial lead was apparently at different levels at three sites,higher in southern suburb and lower in northern suburb.The lead concentration originated from nonferrous metallurgy at three sites from southern suburb, downtown to northern suburb was 113,77.0 and 44.2(ng·m~(-3)),respectively,implying that the major sources for industrial lead were from the south to the Beijing.There is considerable space for reduction of aerosol lead concentration in Beijing.The main object for lead pollution discharge reduction and environmental management measures should aim at nonferrous metallurgy,especially for the field of lead metallurgy located at the south area to the Beijing.The calculation result based on the same chemical analysis data also shows that major source for TSP in Beijing is of soil dust and construction dust,accounting for 72.3%.The other sources such as coal combustion and nonferrous metallurgy account for 13.4% and 9.5%,respectively.