Rare Earth Mining Area Research Articles

Contents of heavy metals in lotus seed from REEs mining area

At rare earth mining area, the pollution of heavy metals has been paid little attention. In lotus seeds and soil samples sampled from a typical rare earth elements mining area were detected the contents of eight kinds of heavy metals (Cr, Mn, Cu, Zn, As, Cd, Hg and Pb) to investigate the pollution from rare earth elements mining by ICP-MS (Inductively Coupled Plasma Mass Spectrometry). The results showed that the contents of the heavy metals Cr, Mn, Cu, Zn, As, Cd, Hg and Pb in lotus seeds were 0.25, 86.94, 8.32, 19.76, 0.13, 0.08, 0.01, and 0.20 μg/g in lotus seeds, respectively, and corresponding contents in soil were 27.68, 168.71, 20.23, 47.16, 1.83, 0.13, 0.04, and 23.15 μg/g. These data showed that the contents of heavy metals in lotus seeds from REEs mining area are no higher than reference area and meet national food safety standards of China.

Rare earth elements in naturally grown fern Dicranopteris linearis in relation to their variation in soils in South-Jiangxi region (Southern China)

Ferns (Dicranopteris linearis) and soils, sampled from four rare earth mining areas and one non-mining area locating in South-Jiangxi region, were chosen for analysis of 15 rare earth elements (REEs) by inductively coupled plasma–mass spectrometry (ICP–MS). The fern samples were divided into 4 parts: root, stem, petiole, and lamina. The soils of the same sites were also sampled, and 4 soil layers were observed at the profile: A (0–20 cm depth), B (20–150 cm depth), C (150–400 cm depth), and D (rock). The distribution patterns and transportation characteristics of REEs of different soil layers and of different parts of D. linearis were studied. The results showed that in the soil layers, the ΣREE (the sum of the concentrations of 15 REEs) of A layer, as well as B layer were lower than that of C layer, but Ce was relatively concentrated in A layer. The ΣREE of different parts of D. linearis were lamina, root>stem>petiole. The REE distribution patterns of D. linearis root were similar to the total REE distribution patterns of the A layer of their host soils, especially to the soluble REE distribution patterns of the A layer of their host soils. The REEs were fractionated in their transportation in D. linearis. The abundances of heavy rare earth elements (HREEs, Gd to Lu and Y) in the stem, petiole, lamina are lower than those in the root.