土壤标准物质中Pb生物可给量的体外模拟试验

基于生理学的体外模拟实验(PBET),旨在测定经口无意摄入的土壤和尘土中的Pb在人体消化道内的生物可给性。采用国家土壤标准物质GBW07429(长江中下游土壤)对体外模拟实验的回收率和精密度进行测定。20次重复测定的结果显示,整个分析流程的回收率(各提取态之和占总量的百分含量)为96.4%～105%,满足体外模拟试验的分析要求。土壤标准物质GBW07429中胃阶段和小肠阶段Pb的生物可给量分别为2.8mg/kg和0.42mg/kg,相对标准偏差均小于15%,具有较好的精密度。研究采用土壤标准物质GBW07429测定了Pb的生物可给量,为分析Pb的生物可给性的体外模拟试验提供一个参考值。

Contents of Bioaccessible Pb from Standard Reference Soil by in Vitro Test

Physiologically based extraction test(PBET) was done to determine the bioaccessbility of Pb in soil and dust which could be incidental ingested through hand-to-mouth transformation.National standard reference material GBW07429 (soil of the middle and lower reaches of the Yangtze River) was used to test the recoveries and precision of the method. Results indicated that the recoveries of the method with 20 repeat measurements accounted for 96.4%to 105%,which can meet the requirement of in vitro test.The bioaccessible Pb contents of the national standard reference soil GBW07429 in stomach and intestinal were 2.8 mg/kg and 0.42 mg/kg respectively,and relative standard deviations of the two stages were both less than 15%,indicating accepted precisions for in vitro test.The study would provide reference value for in vitro test to analysis of bioaccessible Pb by using standard reference soil GB W07429.