Distributions and sources of n-alkanes in PM2.5 at urban, industrial and coastal sites in Tianjin, China

作者：Li Weifang; Peng Yue; Bai Zhipeng^*

来源：Journal of Environmental Sciences, 2010, 22(10): 1551-1557.

DOI：10.1016/S1001-0742(09)60288-6

• PM2.5
• n-alkanes
• distribution pattern
• CPIs
• plant wax

Aliphatic hydrocarbons (n-alkanes) associated with fine particulate matter were determined in the ambient air of urban, industrial and coastal areas in Tianjin, China, where intensive coal burning for industrial and domestic purpose takes place. n-Alkane homologues from C12 to C35 were quantifiable in all samples with C20-C31 being the most abundant species. Average concentrations of the total n-alkanes were 148.7, 250.1 and 842.0 ng/m(3) in July, April and January, respectively. Seasonal variations were mainly attributed to ambient temperature changes and coal combustion for residential heating. Among the three studied areas, the highest levels of n-alkanes were observed in the industrial complex in winter and spring, but in summer the coastal alkane concentration moved up to the highest. A mono-modal distribution for n-alkanes was observed in spring and summer with odd carbon number predominance and a maximum centered at C27-C31, suggesting the release of plant wax into the atmosphere. The bimodal distribution with maxima at C22 and C26 observed in winter indicated a substantial influence of fossil fuel sources. All the CPIs (CPI1, CPI2, CPI3) values, varying between 0.64 and 1.97, indicated the influence of anthropogenic emissions on fine organic aerosols. The estimated contributions of plant wax to total n-alkanes were on average of 12.9%, 19.1% and 26.1% for winter, spring and summer, respectively.

• 出版日期2010
• 单位辽宁省环境监测中心站; 南开大学; 天津市环境保护科学研究院