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Abstract: The concentrations of organic compounds, including n-alkanes and polycyclic aromatic hydrocarbons (PAHs), in fine particles (PM2.5) were measured in an urban area of Guangzhou before, during, and after the 16th Asian Games (9–30 November 2010). Higher average concentrations of n-alkanes and PAHs occurred in the nighttime, presumably due to a restriction on motor vehicle operation during the day and the accumulation of pollutants due to temperature inversions at night. The carbon preference index, contributions of wax n-alkanes, and PAHs diagnostic ratios indicated that the main sources of n-alkanes and PAHs were anthropogenic, especially motor vehicle emissions. The CMAQ model was used to estimate the percentages of biogenic organic aerosol in the total organic aerosol, then the ratios of source marker PAHs to biogenic organic carbon were used to evaluate the air pollution control policies effectiveness during the Asian Games. [Copyright &y& Elsevier]

Ambient air monitoring was conducted at Datianshan landfill, Guangzhou, South China in 1998 to investigate the seasonal and horizontal variations of trace volatile organic compounds (VOCs). Twelve sampling points over the Datianshan landfill were selected and samples were collected simultaneously using CarbontrapTM adsorption tubes. Thirty eight VOCs were detected in the winter, whereas 60 were detected in the summer. The VOC levels measured in summer were alkanes, 0.5–6.5 μg/m3; aromatics, 2.3–1667 μg/m3; chlorinated species, 0.2–31 μg/m3; terpines, 0.1–34 μg/m3; carbonyl species, 0.3–5.6 μg/m3 and naphthalene and its derivatives, 0.4–27 μg/m3. Compared to the summer samples the VOC levels in winter were much lower (mostly 1–2 orders of magnitude lower). The aromatics are dominant VOCs in landfill air both in winter and summer. High levels of alkylbenzene and terpines such as methyl-isopropylbenzene (max 1667 μg/m3) and limonene (max 162 μg/m3) cause undesirable odor. The similar correlation coefficients of BTEX in summer and winter suggest VOCs emissions were from landfill site sources. The variation of BTEX ratio at landfill site is different from that in the urban area of Guangzhou. It shows that the ambient VOCs at landfill site were different from the urban areas. [Copyright &y& Elsevier]