不同体外模拟法提取农田土壤重金属的研究

Study on Extraction of Heavy Metals from Farmland Soil by Using Different in-vitro Digestion Simulative Methods

采用3种体外消化方法(SBET、PBET和SGET),对农田土壤中重金属元素Cu、Zn、Pb和Cd进行了提取效果分析。结果表明:3种方法的模拟消化液对土壤中Cu、Zn和Cd的提取量表现为SBET>PBET>SGET;3种方法的模拟消化液中胃液对土壤中同一重金属的提取量表现为SGET>PBET>SBET;土壤中Cu、Zn、Pb和Cd在PBET和SGET法中经胃液消化的产物进入肠液后溶解量降低。因此,在重金属Cu、Zn、Pb和Cd经土壤-口腔途径对人体健康风险的评价中,基于保护人体健康,可通过由模拟胃液组成的体外消化法来研究它们的生物可接受性。

Three representative in-vitro digestion tests（ SBET,PBET and SGET） were used to extract heavy metals Cu,Zn,Pb and Cd from farmland soil,and their extraction efficiencies were analyzed and compared. The extraction ability of simulative digestive juice of three in-vitro tests for Cu,Zn and Cd showed the following order： SBETPBETSGET. The extraction ability of simulative gastric juice of three in-vitro tests for the same heavy metal in the soil had the sequence of SGETPBETSBET.The dissolved quantity of Cu,Zn,Pb and Cd in intestinal juice after they were digested by the gastric juice of PBET and SGET was decreased. Therefore,in the evaluation of health risk of Cu,Zn,Pb and Cd to human body through soil-oral approach,in order to protect human health,we can use in- vitro simulative gastric juice digestion method to study the bioaccessibility of these heavy metals in soil.