Distribution of rare earth elements in agricultural soil and human body (scalp hair and urine) near smelting and mining areas of Hezhang, China

Abstract

Rare earth elements (REEs) in recent decade are widely used and lead to the accumulation of REE in the environment and human body. The aim of this study was to evaluate the concentrations of REEs in soil and human body (scalp hair and urine) of people living in agricultural soil near smelting and mining areas in Hezhang County, China. The results showed that mean concentrations of determined REEs in agricultural soil from smelting areas were higher than background. However, concentration was slightly higher in soil in mining area. In addition, REEs concentrations of hair and urine in smelting areas were higher than those in mining areas. ΣREEs for soil in mining and smelting areas were 177.79 and 277.06 mg/kg, respectively. ΣREEs for hair in mining and smelting were 1.13 and 1.55 mg/kg, respectively, and ΣREEs for urine in mining and smelting were 0.58 and 0.59 µg/L, respectively. Results showed that La, Ce and Nd were enriched in soil, hair and urine. Eu in smelting area showed a positive anomaly. In smelting and mining areas, females were more likely than male to expose to REEs. The relationship between REEs concentration and age group showed that hair’s high concentrations of REE existed in 18–40 years age for people from smelting areas and females from mining areas. While high concentrations distributed in the age of 41–65 for males from mining area. However, urine did not present similar distribution for different age group. Compared with hair and urine, soil showed the same distribution of REEs. And according to the Ce/Ce* value vs. LaN/YbN ratio showed that hair and soil tended to increase, with the stability of Ce/Ce* value. Thus the distribution of REEs in soil was closely related with the accumulation in human body. This is a preliminary study which may be suggested to the other research, and this study data may be useful for adding up the data pool on REEs levels in China.