某市再生水灌区水土环境中PPCPs污染特征分析

Distribution characteristics of pharmaceuticals and personal care products in water and soil environment in reclaimed water irrigation area of a city

为初步了解再生水灌区土壤环境中药物与个人护理品(PPCPs)的污染特征,识别灌区地下水中PPCPs的主要来源,对某市东南郊Y灌区内的淸灌区、再生水灌区以及湿地三种类型的场地进行了精细剖面钻探工作,采集不同深度土壤、灌区地表水及成井地下水样品,分别对其进行了常规指标和15种PPCPs浓度的测试.结果表明,不同场地土壤中PPCPs含量分布存在差异,土壤剖面中PPCPs含量总体表现为再生水灌区>清灌区>湿地.土壤中PPCPs总浓度平均值为15.6μg/kg,主要以卡马西平CBZ、苯扎贝特BF、吉非罗齐GF、氯霉素CP、吲哚美辛IM为主.灌区地表水中PPCPs总含量明显高于地下水,总浓度平均值分别为272.5ng/L和63.5ng/L,且地表水中,PPCPs含量呈现沿程递减现象.利用Multi-cell基本原理并结合推流的概念刻画PPCPs从地表穿透土壤包气带进入地下水的垂向输移过程,计算结果显示除卡马西平CBZ、甲芬那酸MA和萘啶酸NA外,其余9种PPCPs计算值和地下水中的实测值吻合良好,初步证实再生水是灌区地下水中PPCPs的主要来源.

In order to preliminarily understand the distribution characteristics of pharmaceuticals and personal careproducts (PPCPs) in soil environment, and then identify the main source of PPCPs in groundwater in the farming area ofsoutheast suburban of a city,drilled profiles in irrigation area, reclaimed water irrigation area, and wetland wereinvestigated in detail. In each profile, samples of surface water, groundwater and soil samples from different depths werecollected. The routine indexes and 15target PPCPs of all samples were analyzed. The analytical results indicated that therewas an obvious difference in concentration levels of PPCPs in different areas. Generally, the concentrations of PPCPs inthe soil profiles in reclaimed water irrigation area were the highest, and those in the wet lands were the lowest. Theaverage total concentration of soil PPCPs was 15.6μg/kg. The detected PPCPs mainly includecarbamazepine, bezafibrate,gemifibrozil, chloramghenicol and indometacin. In the irrigation area, the average total concentrations of PPCPs insurface water and in groundwater were 272.5ng/L and 63.5ng/L, respectively. In surface water, there was a trend that theconcentration of PPCPs decreased downwards. By using themixing Multi-cell principle and concept of Push flow, verticaltransport process of PPCPs from soil surface to ground water was depicted. The calculated results of 9selected PPCPs (notincludingcarbamazepine, mefenamicacidand nalidixic acid) in groundwateraccorded well with the measured values. Thispreliminarily indicated that the reclaimed water is the main source of PPCPs in groundwater in the irrigation area.