污灌土壤中多环芳烃的残留水平及其种类分析

Residue Levels and Types of Polycyclic Aromatic Hydrocarbons in Wastewater Irrigated Soil

[目的]观察污水灌溉土壤多环芳烃(PAHs)的残留水平和种类。[方法]选取2个典型污灌农田(A、B)为研究对象,清洁水灌溉农田C为对照,采集土壤样品14个,采用超声振荡法提取土壤中的有机污染物,用高效液相色谱仪(HPLC)对土壤中的16种PAHs进行分析。[结果]A、B两个污灌区土壤PAHs总量分别为1 308.0μg/kg和1 046.2μg/kg,达到了重污染水平,明显高于对照区C(189.1μg/kg,未受污染水平)。污灌区土壤中PAHs主要以4环以上的高环类为主,PAHs主要来源于化石燃料高温燃烧,同时存在石油类的污染。[结论]污水灌溉可导致土壤的PAHs污染。

[Objective] To determine the residue levels and types of polycyclic aromatic hydrocarbons （PAHs） in wastewater irrigated soil. [Methods] Two typical wastewater irrigated farmlands, A and B, were chosen for investigation, and a clean water irrigated farmland C was used as control. Soil samples were collected and organic substances were extracted by ultrasonic oscillation. Sixteen kinds of PAHs were analyzed using high performance liquid chromatography （HPLC）. [Results]The PAHs concentrations in the farmlands A and B were 1 308.0 μg/kg and 1 046.2 μg/kg respectively （categorized as heavily polluted）, and were significantly higher than that in the farmland C, which was 189.1μg/kg （categorized as not polluted）. Most of the soil samples contained PAHs with 4 or more rings which were originated primarily from high temperature combustion of fossil fuels.[Conclusion] Wastewater irrigation may cause soil pollution by PAHs.