典型城市土壤中重金属锑(Sb)的含量分布特征及风险评价

Distribution Characteristics and Risk Assessment of Antimony in Typical Urban Soil

为探讨重金属锑(Sb)在城市土壤中的分布特征和潜在风险,基于上海市102个地块1670个不同深度剖面土壤样品数据,分析4种典型土地利用类型土壤重金属Sb的含量分布特征,并通过潜在生态风险指数法和健康风险评价模型进行风险评价.结果表明,研究区域土壤ω(Sb)的平均值为0.52 mg·kg^(-1),并呈现明显的聚集分布特性;土壤Sb含量随着土壤深度的增加逐渐降低,表层土壤Sb存在一定程度的富集,人类活动影响了土壤中Sb的分布.工业用地表层土壤Sb含量相较于其它3种类型土壤差异显著,其累积程度高于住宅用地和商服用地,农用地Sb含量水平最低.区域整体上处于清洁至尚清洁水平,但工业用地的单项污染指数相对最高,达到轻度污染水平,住宅用地、商服用地和农用地分别为尚清洁或清洁水平;潜在生态风险指数范围为4.23~7.61,区域整体表现为轻微潜在生态风险.工业用地潜在生态风险等级为中等,需引起重视.健康风险评价结果显示土壤Sb非致癌风险较小或可忽略.

In order to study the distribution characteristics and potential risk of antimony(Sb)in urban soil,the concentrations of soil Sb in four different land use types were analyzed based on the data of 1670 soil samples with different vertical profiles in 102 plots in Shanghai.The risks were evaluated using the potential ecological risk index method and health risk assessment model.The results showed that the averageω(Sb)in the study area was 0.52 mg·kg^(-1),and the content of soil Sb gradually declined with the rise in soil profile depth.Sb was enriched in surface soil,which indicated that human activities had caused disturbance to the distribution of Sb in the soil.The content of Sb in the surface soil of industrial land was higher than that of residential land and commercial land,and the content of Sb in agricultural land was the lowest.The single-factor pollution index of industrial land was the highest,reaching a slight pollution level,whereas the residential land,commercial land,and agricultural land were at even-clean or clean levels,respectively.The whole region showed slight ecological risk,with the potential ecological risk index ranging from 4.23 to 7.61.The potential ecological risk level of industrial land was moderate,which needs to be addressed.The results of health risk assessment showed that the non-carcinogenic risk of Sb in the soil was low;however,it is of great concern to residents,especially children,when on residential land.