As medicinal plants can accumulate harmful metals from the native soil, people's consumption of these materials may cause the human body to accumulate toxic metal elements. This has given rise to people’s concerns about the quality and safety of Chinese medicinal materials. This research aims to determine the levels of Cr, Ni, Cu, Zn, As, Cd, Hg and Pb in four medicinal plant species (Aster tataricus L.f., Salvia miltiorrhiza Bge, Radix Aucklandiae, Scutellaria baicalensis Georgi) and their native soil. All samples were collected from Qian’an city, beside Yanshan Mountain Range in Tangshan city, east Hebei Province, north China. The contents of heavy metals we detected in the soil conformed to the current limits. However, the Cd and Hg in the soil had a very high potential ecological risk because of their contents higher than the base level of local soil. The contents of Cu, Cd, Hg and Pb in some medicinal herbs exceeded the standards. The content of Cu in Radix Aucklandiae exceeded the standard by 3 times, and others exceeded the standard by less than one time. The comprehensive health risk assessment of heavy metals with chronic non-carcinogenic effects for human body showed that none of the four medicinal herbs can create a health risk. Thus, there is no strong positive correlation between heavy metal pollution in medicinal herbs and that in the native soil. Further research should be investigated to the connection between the heavy metal levels in the soil and plants, and the comprehensive effects of soil, air and irrigation water on heavy metal pollution of Chinese herbal medicines. We also recommend that Chinese herbal medicines should be cultivated and gathered only from controlled or uncontaminated areas.

由于药用植物可以从原生土壤中积累有害金属，人们食用这些材料可能会导致人体积累有毒金属元素。这引起了人们对中药材质量安全的担忧。本研究旨在测定四种药用植物（紫菀、丹参、黄芩、黄芩）中 Cr、Ni、Cu、Zn、As、Cd、Hg 和 Pb 的含量。) 和他们的本土土壤。所有样品均采集自华北河北省东部唐山市燕山山脉旁的迁安市。我们在土壤中检测到的重金属含量符合现行限值。然而，土壤中的Cd和Hg含量高于当地土壤的基准水平，具有很高的潜在生态风险。部分药材中Cu、Cd、Hg、Pb含量超标。奥克兰根中Cu的含量超标3倍，其他超标不到1倍。对人体具有慢性非致癌作用的重金属的综合健康风险评估表明，四种药材均不会产生健康风险。因此，药材中的重金属污染与原生土壤中的重金属污染之间没有很强的正相关关系。进一步研究土壤中重金属含量与植物的关系，以及土壤、空气和灌溉水对中药材重金属污染的综合影响。我们还建议只在受控或未受污染的地区种植和采集中草药。