基于健康风险评价的种植黄芩中重金属的安全限值研究

Study on Safety Limits of Heavy Metals in Planted Scutellaria baicalensis Georgi Based on Health Risk Assessment

近年来中药材的重金属超标问题已经引起了各界的广泛关注,但世界各国家和地区对于药用植物中重金属的安全限量值缺乏统一规定。黄芩(ScutellariabaicalensisGeorgi)是中国临床常用的传统大宗中药材。基于健康风险评价方法推定了黄芩所含类金属As、重金属Cd、Cr、Cu、Ni、Pb和Zn的安全限量值并评价了黄芩药材和饮片的污染状况。采集了北京市门头沟区人工栽培的一年生至五年生的黄芩根样品共25份,并从安国和亳州两大药材市场分别购进黄芩饮片各5份,利用电感耦合等离子体原子发射光谱法(ICP-AES)测定了样品中7种重金属的含量;将2015版《中国药典》所含118种黄芩制剂依据功效主治分为7类,结合其各自的用药规律,基于重金属可能给人体造成的致癌和非致癌健康风险可接受水平,推得黄芩所含7种重金属的安全限量值,并以此为标准评价了黄芩样品的污染状况。黄芩所含7种重金属As、Cr、Pb、Cd、Cu、Ni和Zn的安全限量值分别为0.2、0.5、28.5、1.2、48.1、24.1、361.0 mg·kg^(-1);该限值与已有的《药用植物及制剂进出口绿色行业标准》和ISO标准相比,增加了重金属Cr、Ni和Zn的安全限量值;且对于具有经口摄入致癌毒性的As、Cr和Pb,考虑了黄芩常年服用的致癌风险。本研究中As的安全限量值相对较低,而Cu和Pb相对较高,Cd处于以上两个标准值之间;若以此为评价标准,两种来源的黄芩样品中所含有的重金属只有As和Cr出现了不同程度的超标现象。中药材所含重金属安全限量值的制定最好因药而异,以期取得最佳效果。

In recent years, the problem of excessive heavy metals in Chinese herbal medicines has attracted wide attention, but there is no uniform regulation on the safety limits of heavy metals in various countries and regions around the world. Scutellaria baicalensis Georgi is a traditional Chinese herbal medicine commonly used in clinical practice in China. The purpose is to estimate the safety limits of seven heavy metals such as As, Cd, Cr, Cu, Ni, Pb and Zn in cultivated S. baicalensis and evaluate the pollution status of heavy metals in S. baicalensis original medicine and pieces. We have collected 25 samples in total of annual, biennial,triennial, quadrennial and quinquennial S.baicalensis Georgi roots cultivated in Mentougou District, Beijing and purchased 5 samples from each of the two medicinal markets in Anguo and Bozhou. Seven heavy metals in samples were detected by ICP-AES. The 118 kinds of S. baicalensis preparations from the 2015 edition of the Chinese Pharmacopoeia were divided into 7 categories according to their efficacy. Combined with category-specific usage(dosage and treatment course) of preparations and the contents of S.baicalensis in the preparations, the safety limits of seven heavy metals in S. baicalensis were estimated based on the allowable carcinogenic and non-carcinogenic health risks levels posed by heavy metals. According to these safety limits, the heavy metal pollution status of S. baicalensis samples was evaluated. The safety limits of the seven heavy metals contained in S. baicalensis were0.2, 0.5, 28.5, 1.2, 48.1, 24.1, 361.0 mg·kg^-1 respectively, and the concentrations of the two heavy metals As and Cr in the samples have exceeded the suggested safety limits to different degrees. This study added the safety limits of Cr, Ni and Zn and examined the cancer risk of As, Cr and Pb for the probable perennial use compared with the Green Trade Standards for the Importing and Exporting of Medicinal Plants and Preparations and ISO standards. The safety limit of As was relatively low, while Cu and Pb were relatively high, and Cd was between the above two standard values. The safety limits of heavy metals in traditional Chinese medicines should be enacted by medicinal plant species.