Determination of heavy metal elements in Chuanmingshen violaceum by ICP-MS / 中草药

ABSTRACT

Objective: To quantify the contents of heavy metal elements in the roots of Chuanmingshen violaceum (Chuanmingshinis Violacei Radix, and Chuanmingshen) and to evaluate its safety. Methods: An inductively coupled plasma mass spectrometric (ICP-MS) method was developed to quantify six heavy metal elements, i.e. lead (Pb), cadmium (Cd), mercury (Hg), copper (Cu), arsenic (As), and chromium (Cr) in Chuanmingshinis Violacei Radix. A total of 33 Chuanmingshinis Violacei Radix samples were collected from eight counties/districts in Sichuan province of China, processed and then quantified for the contents of these elements. Moreover, the eight counties/districts were divided into four cultivation areas of Chuanmingshinis Violacei Radix based on the geographical location and ecological environment. The differences of heavy metals were compared by statistical analysis. Results: The total content of each element in the 33 samples of Chuanmingshinis Violacei Radix were Pb ≤ 0.256 μg/g, Cd ≤ 0.235 μg/g, Hg ≤ 0.123 μg/g, Cu ≤ 3.963 μg/g, and Cr ≤ 2.145 μg/g; As below the detection limit, the findings were in line with the "Green Trade Standards of Importing and Exporting Medicinal Plants and Preparations" in China. Comparing the amount of heavy metal elements in the samples of Chuanmingshinis Violacei Radix, it was found that the contents of the six heavy metal elements were varied among the four cultivation areas. Except for the difference of Pb content which was significant between the two cultivation areas (P < 0.05), other heavy metal elements in these samples among the four cultivation areas were not significantly different. Conclusion: The developed ICP-MS method is suitable to accurately quantify the content of heavy metal elements in the samplesof Chuanmingshinis Violacei Radix. On the basis of the level of heavy metal elements, Chuanmingshinis Violacei Radix is considered safe and the current cultivation areas are suitable for the cultivation of C. violaceum.