关键词: 矿区, 土壤, 砷, 风险

Abstract: A systematic investigation was carried out on the arsenic content in the soils and plants surrounding Shimen arsenic sulphide mine. The arsenic content in top soils (0-20 cm) was averagely 99.51 mg·kg^-1, being 5.34 times higher than that of the background value in Hunan Province and 8.70 times higher than that of local farmland soil. The topsoil arsenic content in paddy field and dry land was 43.51 and 115.1 mg·kg^-1, respectively, being 0.45 and 1.87 times higher than that of the grade II level (paddy field 30 mg·kg^-1; dry land 40 mg·kg^-1) commended by the National Soil Quality (GB 15618-1995), and the corresponding arsenic exceeding rate was 62.5% and 50.0%, respectively. The arsenic content in edible parts of foodstuff, vegetables, and fruits was 0.16, 0.06, and 0.01 mg·kg^-1, respectively, and the arsenic exceeding rate of crop samples compared to food security standard ranked in the order of foodstuff ＞ vegetables ＞ fruits. Rice and sweet potato were relatively seriously contaminated by arsenic. The highest arsenic content of rice was up to 0.84 mg·kg^-1, which was 4.6 times higher than that of the National Standard, with the exceeding rate of 62.5%. Statistical analysis demonstrated that there was a positive correlation between the arsenic contents of soil and plant. The average daily intake of arsenic by local people through the consumption of the crops was 6.416 μg·kg^-1·d^-1, which was much higher than the standard commended by WHO, and the related health risk index was 21.39, which was 14.39 times higher than that in the control region.

Key words: mining area, soil, arsenic, risk