靶器官毒性剂量法在玉竹中铅、镉和砷联合暴露评估中的应用

Application of target-organ toxic dose modification of HI method in the assessment of combined exposure to lead, cadmium and arsenic in Polygonatum odoratum (MilL) Druce

目的:对于玉竹中铅(Pb)、镉(Cd)和砷(As)的残留量进行测定,探索靶器官毒性剂量法在评估中药中重金属联合暴露风险中的应用。方法:根据玉竹中Pb, Cd和As的残留量监测数据,计算其暴露量。采用危害指数(HI)法对Pb, Cd和As联合暴露产生的健康风险进行初步筛查。若危害指数(HI)值>1或其中2种或2种以上重金属的危害商(HQ)值>0.1,则针对不同毒理学终点,采用靶器官毒性剂量(TTD)法,对于Pb, Cd和As的累积风险进行更加精确的评估。结果:40批玉竹中Pb和As的合格率为100%,2批Cd的含量超过限量标准。HI法的评估结果表明,3批玉竹的HI值>1,并且其中6批次玉竹存在2种或2种以上重金属的HQ值>0.1的情形。TTD法评估结果表明,对于作用终点神经系统,5批次玉竹的HI值>1;对于作用终点肾脏,2批次玉竹的HI值>1,对于以上情况,风险需要被关注。结论:本研究首次提出中药材中重金属的累积风险评估原则,为中药中外源性有害残留物风险评估的方法开发提供了新的思路,为制定更加科学的限量标准提供了技术支撑。

Objective: To determine the residue of lead(Pb), cadmium(Cd) and arsenic(As) in Polygonatum odoratum(MilL) Druce and to explore the application of target-organ toxic dose modification of HI(TTD) method in assessing the combined exposure risk to heavy metals in traditional Chinese medicines(TCMs). Methods: According to the monitoring data of Pb, Cd and As in Polygonatum odoratum(MilL) Druce, the exposure doses were calculated. The health risk caused by combined exposure to Pb, Cd and As was preliminarily screened by Hazard Index(HI) method. If HI was greater than 1 or the Hazard Quotients(HQs)of more than two kinds of heavy metals were greater than 0.1, a more accurate TTD method was used to evaluate the cumulative risks of Pb, Cd, and As according to different toxicological end-points. Results: The qualification rates of 40 batches of Polygonatum odoratum(MilL) Druce regarding contents of Pb and As were 100%;however, 2 batches of Cd contents exceeded the limit standard. The HIs of three batches of samples were >1. The HQs of two or more heavy metals were higher than 0.1 in six batches of samples. TTD results revealed that for the end-point of nervous system, the HIs of 5 batches of samples were > 1. For the end-point of kidney, His for 2 batches of samples were >1. Conclusion: This study for the first time put forward the principle of cumulative risk assessment of heavy metals in TCMs, which paves a new way for the development of risk assessment methods of exogenous harmful residues in TCMs, and provides technical support for formulating scientific limit standards.