黄骅市冬枣和果园土壤中重金属元素分析与膳食暴露风险评估

Risk assessment of dietary exposure and analysis of heavy metals in orchards soil and Ziziphus jujuba Mill. cv. ‘Dongzao’ fruit in Huanghua City

目的 分析黄骅市冬枣和果园土壤中重金属元素并评估膳食暴露风险。方法 采集黄骅市冬枣产区27个果园的冬枣样品和对应的果园土壤样品,采用电感耦合等离子质谱法(inductivelycoupledplasmamass spectrometry, ICP-MS)和直接测汞仪对其中的Cr、Cu、Cd、As、Pb和Hg进行测定。根据美国环境保护局(the United States Environmental Protection Agency, USEPA)推荐健康风险模型评价法,对冬枣中的Cr、Cu、Cd、As、Pb和Hg的健康风险进行定量评估。结果 所采集样品的果园土壤中Cd、Pb、Cr、Cu、Hg和As含量均低于GB15618—2018《土壤环境质量农用地土壤污染风险管控标准(试行)》中规定的“农用地土壤污染风险筛选值”;不同果园的冬枣中As、Cd、Pb、Cr、Cu、Hg的检出率分别为100.0%、88.9%、96.3%、96.3%、100.0%、3.7%;6种元素的目标危害系数法(target hazard quotient, THQ)<1,累积目标危害系数(total target hazard quotient, TTHQ)<1,说明膳食暴露风险均可接受;Pb在土壤和冬枣的样品中呈显著正相关性,其他元素在两者间均没有明显的相关性。冬枣样品中重金属元素As和Cr可能来源于外部投入品。结论 黄骅市生产的冬枣重金属元素的膳食摄入风险处于安全水平,消费者可放心食用。外部投入品可能是冬枣重金属污染的来源之一,应引起密切关注。

Objective To analyze the heavy metal elements in orchards soil and Ziziphus jujuba Mill. cv.‘Dongzao’ fruit in Huanghua City and evaluate the dietary exposure risk. Methods Twenty-seven Ziziphus jujuba Mill. cv. ‘Dongzao’ fruit samples and their corresponding orchards soil samples from Huanghua City were collected.The content of Cr, Cu, Cd, As, Pb and Hg was detected by inductively coupled plasma mass spectrometry(ICP-MS)and direct mercury analyzer. According to the health risk model evaluation method recommended by the United States Environmental Protection Agency(USEPA), the health risk of Cr, Cu, Cd, As, Pb and Hg in Ziziphus jujuba Mill. cv. ‘Dongzao’ fruit was quantitatively evaluated. Results The content of Cd, Pb, Cr, Cu, Hg and As in orchards soil was all lower than “risk screening values for soil contamination of agricultural land” regulated in GB 15618—2018 “Soil environmental quality-Agricultural land soil pollution risk control standard(Trial)”;the detection rates of As, Cd, Pb, Cr, Cu and Hg in Ziziphus jujuba Mill. cv. ‘Dongzao’ fruit from different orchards were 100.0%,88.9%, 96.3%, 96.3%, 100.0% and 3.7%, respectively;for 6 kinds of heavy metals, all target hazard quotient(THQ)<1, total target hazard quotient(TTHQ)<1, indicating that dietary exposure and risk assessment was acceptable;for Pb, there was a significant positive correlation between Ziziphus jujuba Mill. cv. ‘Dongzao’ fruit and orchard soil samples, while no such relations for the other heavy metals;As and Cr in Ziziphus jujuba Mill. cv.‘Dongzao’ fruit might come from external inputs. Conclusion The risk of dietary intake of heavy metals in Ziziphus jujuba Mill. cv. ‘Dongzao’ fruit produced in Huanghua City is at a safe level, and the consumers can eat it with confidence. As external inputs may be one of the sources of heavy metal pollution to Ziziphus jujuba Mill. cv.‘Dongzao’ fruit, it should be paid close attention to.