Origin Traceability of Tobacco Leaves by Multi-elements Analysis Using Inductively Coupled Plasma Atomic Emission Spectroscopy and Cluster Analysis

An Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) method was developed for determination of 16 elements (As, Se, Zn, Pb, Cd, Ba, Fe, B, Mn, Cr, Mg, V, Ca, Cu, Al, K) in tobacco leaves. Collected 36 samples from Peru, Zimbabwe, and China were analyzed. The results showed that the content of Cd, Pb, As, Cr and other heavy metals in all samples did not exceed the limit of China national regulation. Principal component factor (PCA) analysis indicated that the studied 16 elements are not well correlated. The variations of elements in tobacco leaves was attributed to the difference of environmental soil rather than the result of tobacco secondary metabolism. 36 samples can be approximately divided into 10 groups. This mathematical model can serve as a traceability tool for tobacco leaf products. This method may facilitate the tobacco selection and quality identification.