Concentrations and health risk assessment of rare earth elements in soil and vegetables from a mining area in Fujian Province

Concentrations of rare earth elements (REEs) in cultivated soils and eight vegetables from a mining area in Changting County of Fujian Province were surveyed. The concentrations of REEs of cultivated soils exceeded the soil background value of Fujian Province, while the concentrations of REEs of taro (3.68 mg·kg^-1 fresh weight) and water spinach (0.92 mg·kg^-1·d^-1) exceeded the maximum permissible concentration of REEs in vegetables (0.7 mg·kg^-1·d^-1) in the NFHSC. The concentrations of REEs of the eight vegetables declined in the order of taro > water spinach > lettuce > pakchoi > long bean > eggplant > white radish > Chinese cabbage. REE concentrations of leafy vegetables were higher than those of the non-leafy vegetables. REE concentrations in local resident's blood and hair were 155.6 and 9.6 times higher than those of the general population, respectively. The average concentrations of REEs in well water from the mining area were 119 times higher than those in the drinking water of Fuzhou City. The average daily intake of REEs of local inhabitants was estimated to be 12.5 mg·kg^-1·d^-1, exceeding values harmful to human health (6.0~6.7 mg·kg^-1·d^-1). The local inhabitants were threatened by health risks due to high REE exposure from vegetable consumption. Some vegetables had greater concentrations of REEs than others, therefore local farmers should choose vegetables with low REE concentrations for reducing health risk associated with high intake of REEs.