Regional Distribution and Composition Characteristics of 16 Rare Earth Elements in Tea from Different Producting Areas in Shaanxi Province

Samples of green tea, black tea, oolong tea, and Fuzhuan tea from different producing areas in Shaanxi province were randomly collected, and 16 REE were determined by inductively coupled plasma mass spectrometry (ICP-MS), to understand the regional distribution and composition characteristics of 16 REE in tea of southern Shaanxi tea areas (Shangluo, Ankang and Hanzhong) and Xianyang tea area in Shaanxi province. The results showed that all 16 REE were detected in tea samples, and the total light rare earth element (LREE) mass fraction (∑w_LREE) accounted for 72.2% of the total REE mass fraction (∑w_REE), and the total content of Ce, La, Nd accounted for 63.8% of ∑w_REE, with the ration of ∑w_LREE to the total heavy rare earth element (HREE) mass fraction (∑w_HREE) of 2.59, showing that LREE fractionation enrichment and HREE fractionation depletion existed; ∑w_REE in Fuzhuan tea from Xianyang was higher than those from southern Shaanxi tea areas, ∑w_REE in Shangluo from southern Shaanxi tea areas was higher than those in Ankang and Hanzhong, and there was a slight difference of ∑w_REE in different producing areas in southern Shaanxi. The contents of Ce, Nd, Gd, Dy, Er, and Yb in tea from each producing area were significantly higher than those of elements on both sides (arranged by atomic number), which could be used as the characteristics of REE in tea; Fuzhuan tea had a high ∑w_REE, followed by black tea, green tea, and oolong tea; the correlation between HREE was good, better than between LREE, LREE and HREE.