鱼腥草中重金属含量特征及健康风险评价

Analysis and Health Risk Assessment of Heavy Metal in Houttuynia Cordata Thunberg

以遵义市市售鱼腥草和野生鱼腥草为研究对象,采用《食品安全国家标准食品中多元素的测定》(GB 5009.268—2016)中的微波消解法,电感耦合等离子体质谱仪(ICP-MS)测定了鱼腥草中铅(Pb)、铬(Cr)、镉(Cd)、砷(As)的含量。对比分析了市售鱼腥草和野生鱼腥草不同部位(根须和地下茎)的重金属分布差异,并运用内梅罗综合污染指数法和单因子污染指数法及目标危险系数,初步评估居民通过食用鱼腥草摄入Pb、Cr、Cd和As的健康风险。结果表明,市售鱼腥草和野生鱼腥草样品中Pb、Cr、Cd和As均有不同程度超标,市售鱼腥草和野生鱼腥草根须中Pb、Cr、Cd、As含量均高于地下茎。市售鱼腥草根须和地下茎的重金属污分别达到严重污染和轻度污染(P综分别为20.8和1.1),野生鱼腥草根须和地下茎中重金属污均属于严重污染(P综分别为92.5和5.9)。市售鱼腥草和野生鱼腥草中单一重金属的健康风险(THQ)均表现为Cr>Cd>Pb>As。市售鱼腥草地下茎中复合健康风险(TTHQ)<1,说明不存在明显的健康风险,但野生鱼腥草地下茎中TTHQ为1.139,存在明显的健康风险。由于鱼腥草根须中重金属含量较高,因此建议在食用鱼腥草时去除根须,从而降低健康风险。

In this study,the contents of lead(Pb),chromium(Cr),cadmium(Cd)and arsenic(As)in Houttuynia cordata Thunberg(HCT)sold in Zunyi City and wild HCT in surrounding towns were determined by inductively coupled plasma-mass spectrometry(ICP-MS)using the microwave digestion method in the national food safety standard determination of multi elements in food(GB 5009.268-2016).The distribution differences of heavy metals in different parts(roots and underground stems)of HCT and wild HCT were compared and analyzed,and the health risks of residents ingesting Pb,Cr,Cd and As by eating Houttuynia cordata Thunb were preliminarily evaluated by using Nemero comprehensive pollution index method,single factor pollution index method and target risk coefficient.The results showed that Pb,Cr,Cd and As in the collected samples of HCT and wild HCT exceeded the standard in varying degrees.The contents of Pb,Cr,Cd and As in commercial HCT were significantly higher than those in underground stems,which were 9.7 times,5.3 times,19.9 times and 9.0 times respectively.The roots and underground stems of HCT on the market are seriously polluted and slightly polluted respectively(P-complex is 20.8 and 1.1 respectively),while the roots and underground stems of wild HCT are seriously polluted by heavy metals(P-complex is 92.5 and 5.9 respectively).The target hazard coefficient(THQ)of a single heavy metal in both commercial and wild HCT was Cr>Cd>Pb>As.The TTHQ of underground stems of commercial HCT was less than 1,indicating that there was no obvious health risk,but the TTHQ in the underground stems of wild HCT was 1.139,indicating obvious health risk.Due to the high content of heavy metals in the roots of HCT,it was recommended to remove the roots when eating HCT so as to reduce the health risk to residents.