Distribution and fractionation of rare earth elements in soil–water system and human blood and hair from a mining area in southwest Fujian Province, China

Accumulations of rare earth elements (REEs) in human body through multiple pathways including food ingestion, air inhalation and dermal absorption have received considerable attention due to their chronic toxicity to human health. The distribution and fractionation of 14 REEs were conducted in soil, well water, human blood and hair in the vicinity of a large-scale mining site in southwest Fujian Province, China. The LREEs/HREEs ratios were 9.17 for soil, 2.18 for water, 36.93 for human blood and 7.24 for human hair, respectively. The distribution patterns of REEs in soil, human blood and hair samples were characterized by LREEs enrichment and HREEs depletion, but LREEs depletion and HREEs enrichment in water sample. La_N/Yb_N values of these samples ranged from 0.41 to 1.83, La_N/Sm_N values from 0.43 to 4.92, and Gd_N/Yb_N values from 0.81 to 4.71. Soil and human blood showed enrichments of Ce, Gd and Er, but water showed a depletion of Ce. In addition, the normalized patterns showed a weak negative anomaly of Eu in soil and a weak negative anomaly of Nd in human blood and hair. Consequently, enrichment and depletion of REEs differ significantly among soil, water and human blood and hair, thus the REEs after entering into human body can undergo fractionation effects.