广西、广东肉桂中5种元素的含量测定及分析

Determination and analysis of five elements in Cinnamomi Cortex from Guangxi and Guangdong

目的:本实验收集广西、广东肉桂样品80批,广西主要种植基地土壤样品13批,利用电感耦合等离子体质谱法(ICP-MS)测定上述样品中5种元素包括铜、砷、镉、汞、铅的含量,并对上述样品中元素量进行比较分析,为肉桂规范化种植选地提供科学依据。方法:样品经微波消解后,采用ICP-MS法测定铜、砷、镉、汞、铅5种元素的量,同时对镉含量不合格肉桂药材做出初步的风险评估。结果:测定结果表明:5种元素线性关系良好(r≥0.999 2),加样回收率为89.9%~98.7%,RSD 0.36%~4.9%。所测80批肉桂药材中78批样品镉超标,2批肉桂药材铅超标;肉桂药材镉超标率为97.5%,铅超标率为2.5%,铜、砷、汞均未超标;土壤样品中铜超标率为23.1%,砷和铅超标率均为30.8%;镉超标率为38.5%,汞含量未超标。结论:本方法操作简单、快速,且灵敏度高,样品污染风险小,能够对肉桂样品中痕量元素进行定量分析。建议在选择肉桂种植基地时应综合考虑上述5种重金属元素的超标问题;建议将肉桂镉限量标准提高至0.6 mg·kg^(-1)。

Objective：In this study,80 batches of Cinnamomi Cortex from Guangxi and Guangdong and 13 batches of soils from the main planting base in Guangxi were collected. And 5 elements（Cu,As,Cd,Hg,and Pb）were determined by inductively coupled plasma mass spectrometry（ICP-MS）method. By comparing the determination results,scientific basis for the good agricultural practice of Cinnamomum cassia Presl was provided. Methods：After microwave digestion,Cu,As,Cd,Hg and Pb were determined by ICP-MS,at the same time,preliminary risk assessment was conducted for the unqualified samples. Results：All the 5 elements had good linearities（r ≥0.999 2）within the linear ranges,with the average recovery from 89.9% to 98.7% with RSDs from 0.36% to 4.9%. The results showed that contents of Cd and Pb exceeded the limit of the standard and the percentages were 97.5% and 2.5%,respectively,while other 3 elements conformed to the standards. In 13 determined soil samples,contents of Cu,Cd,As and Pb were all above the limit（the percentages were 23.1%,38.5%,30.8%,30.8%,respectively）,while the content of Hg conformed to the standards. Conclusion：This method is simple,rapid and sensitive,and the samples are not easy to be contaminated,which could be applied to quantitative analysis of trace elements in Cinnamomi Cortex. It was suggested that the pollution of Cu,Cd,As,Pb and Hg should be c-onsidered when choosing the GAP planting base,and the limits standard of Cd might be raised to 0.6 mg·kg^-1.