2+2014年采用盆栽实验培植小白菜、萝卜和辣椒，以清水、清水+Pb、再生水、再生水+Pb (Pb=0.2 mg/L)溶液灌溉，采用修正的BCR法测定供试水样、土壤、蔬菜和盆底渗滤物中Pb的形态。结果表明：清水和再生水中的Pb主要以水溶态B0存在，总量均未超过国家《农田灌溉水质标准(GB5084—2005)》。土壤和渗滤物中的Pb以残渣态B4为主，总量均未超出《土壤环境质量标准（GB15618—1995）》二级标准。蔬菜中的Pb主要以水溶态B0和可氧化态B3存在，3种蔬菜可食用部分Pb含量为小白菜＞萝卜＞辣椒，均超出《食品安全国家标准中污染物限量（GB2762—2012）》中Pb的限量。农田灌溉用水不仅要严格控制Pb总量，更须关注其有效形态含量。%In 2014, pot experiments were carried out on pakchoi, radish and chili with irrigation by tap water, tap water + Pb, 2+reclaimed water, and reclaimed water + Pb (Pb=0.2 mg/L) respectively. Modified BCR method was used for chemical speciation of Pb in the test water samples, soils, vegetables and soil leachate. The result showed that Pb in the tap water and reclaimed water was mainly in the presence of water-soluble B0, with total amount below the limits in the Standards for Irrigation Water Quality (GB5084-2005). Pb in the soils and soil leachate was mainly in the existence of residue form B4, with total amount below level II in the Environmental Quality Standard for Soils (15618GB-1995). Pb in the vegetables mainly existed in water-soluble B0 and oxidizable B3, and Pb contents in the edible parts ofthesethree vegetables all exceeded the limits in the Pollutant Limits of the National Standards for Food Safety (GB2762-2012), with maximal in pakchoi followed by radish and chili in a descending order. Therefore, total amount of Pb in irrigation water should be strictly controlled with more focus on the content of effective forms for agricultural food safety.
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