Masih Amit, Masih Jamson, Taneja Ajay
Analytical Research Lab, Department of Chemistry, St Andrew's College, Gorakhpur 273001, India.
J Environ Monit. 2012 Jan;14(1):172-80. doi: 10.1039/c1em10567a. Epub 2011 Nov 21.
Soil is the major environmental reservoir of organic compounds and soil-air exchange is a key process in governing the environmental fate of these compounds on a regional and global scale. Samples of air and soil were collected to study the levels of PAHs in the air and soil of the Agra region. Concentrations of PAH measured at four locations in the city of Agra, covers industrial, residential, roadside and agricultural areas. Samples were extracted with hexane by ultrasonic agitation. Extracts were then fractioned on a silica-gel column and the aromatic fraction was analysed by GC-MS. The mean concentration of the total PAH (T-PAH) in the air of Agra was 24.95, 17.95 and 14.25 ng m(-3), during winter, monsoon and summer respectively. The average concentration of T-PAH in the soil of Agra was 12.50, 8.25 and 6.44 μg g(-1) in winter, monsoon and summer seasons respectively. The aim of this study was to investigate the rate of approach to equilibrium partitioning of PAHs between air and soil compartments and to determine the direction of net flux of the studied PAH between air and soil. Calculated soil-air fugacity quotients indicate that the soil may now be a source of some lighter weight PAHs to the atmosphere, whereas it appears to be still acting as a long-term sink for the heavier weight PAHs to some extent in this region.
土壤是有机化合物的主要环境储存库，土壤-空气交换是在区域和全球尺度上控制这些化合物环境归宿的关键过程。采集了空气和土壤样本，以研究阿格拉地区空气和土壤中多环芳烃（PAHs）的含量。在阿格拉市的四个地点测量了PAHs的浓度，涵盖工业区、居民区、路边和农业区。样本通过超声搅拌用己烷萃取。萃取物随后在硅胶柱上进行分离，芳香族部分通过气相色谱-质谱联用仪（GC-MS）进行分析。阿格拉地区空气中总PAH（T-PAH）的平均浓度在冬季、季风期和夏季分别为24.95、17.95和14.25 ng m(-3)。阿格拉地区土壤中T-PAH的平均浓度在冬季、季风期和夏季分别为12.50、8.25和6.44 μg g(-1)。本研究的目的是调查PAHs在空气和土壤隔室之间达到平衡分配的速率，并确定所研究的PAH在空气和土壤之间净通量的方向。计算得出的土壤-空气逸度商表明，目前土壤可能是一些较轻重量PAHs向大气的来源，而在该地区，土壤在某种程度上似乎仍在充当较重重量PAHs的长期汇。
