Identifying Dominant Sources of Respirable Suspended Particulates in Guangzhou,China

Abstract

Respirable suspended particulates (RSP, i.e., particles with an aerodynamic diameter of 10 μm or less) were measured in 2004 and 2005 at seven sites in the rapidly developing Guangzhou area of China. The average RSP concentration was 126 μg m⁻³, a high level that could be very harmful to human health. The chemical species composition of the RSP, including organic and elemental carbon, water-soluble ions, and elemental compositions, was also analyzed. The organics and sulfate may be the major components of RSP mass concentrations. Positive matrix factorization (PMF) was used to identify the sources of RSP as secondary sulfates (32%), secondary nitrates (6%), biomass burning (15%), coal fly ash/cement (18%), sea salt (3%), crustal dust (5%), vehicle exhaust (6%), and coal-fired power plants (3%). Reducing coal combustion and controlling vehicle emissions would alleviate RSP pollution, as most of the precursors were components of coal burning emissions and vehicular exhaust.