土壤-农产品重金属累计特征及健康风险评价——以三江平原东部某典型农业区为例

Accumulation Characteristics and Risk Assessment of Heavy Metals in Soil-agricultural Products--Taking a Typical Agricultural Area in Eastern Sanjiang Plain as an Example

为掌握三江平原东部某典型农业区农田土壤和农产品重金属累计特征及评价其健康风险,本文以三江平原东部面积约180 km^(2)的某典型水稻种植区为研究对象,采用梅花法进行布点取样,共采集土壤样品和农产品样品各50件,采用电感耦合等离子体质谱仪、原子荧光分光光度对土壤和农产品中Cr、Ni、Cu、Zn、Cd、Pb、As、Hg重金属含量进行测定,采用污染负荷指数法分析土壤重金属污染水平,运用重金属健康风险评估模型评估农产品中重金属的非致癌和致癌风险。结果表明,研究区土壤重金属近半数点位处于中等污染水平,水稻中Ni和As超标可能造成食品安全风险。研究区水稻样品中As是非致癌风险的主要污染物,通过摄入研究区水稻暴露于重金属As会对人类健康造成非致癌风险;Ni、Pb、As和Cr是致癌风险的主要污染物,通过摄入研究区水稻暴露于Ni、Pb、As和Cr将会对人类造成致癌风险。研究结果可为粮食作物安全和环境管理提供决策依据。

In order to grasp the cumulative characteristics of heavy metals in farmland soil and agricultural products in a typical agricultural area in eastern Sanjiang plain and evaluate their health risks,taking a typical rice planting area with an area of about 180km^(2) in eastern Sanjiang plain as the research object,by using plum blossom method for sampling,a total of 50 soil and agricultural product samples have been collected.By using inductively coupled plasma mass spectrometry and atomic fluorescence spectrophotometry,the content of Cr,Ni,Cu,Zn,Cd,Pb,As and Hg heavy metals in soil and agricultural products have been measured.The pollution load index method has been used to analyze the level of soil heavy metal pollution,and a heavy metal health risk assessment model has been used to evaluate the non carcinogenic and carcinogenic risks of heavy metals in agricultural products.It is indicated that nearly half of the soil heavy metal sites in the study area are at a moderate pollution level,and excessive Ni and As in rice may cause food safety risks.After conducting a heavy metal health risk assessment,it is found that As is the main non carcinogenic pollutant in the rice samples from the study area.Exposure to heavy metal As by ingesting rice from the study area can pose a non carcinogenic risk to human health;Ni,Pb,As,and Cr are the main pollutants at risk of carcinogenesis.Exposure to Ni,Pb,As and Cr through ingestion of rice in the study area will pose a carcinogenic risk to humans.The research results will provide a decision-making basis for food crop safety and environmental management.