头花蓼对土壤中锑的累积特征及健康风险评价

为有效控制头花蓼重金属污染问题、保障头花蓼药用安全提供科学依据,通过盆栽试验,研究不同浓度锑(Sb)污染土壤中头花蓼(Polygonum capitatum)对Sb的吸收累积特征及头花蓼中Sb对人体的健康风险影响,并预测头花蓼食用量在人体可接受范围内时头花蓼种植土壤中Sb的安全限值。结果表明,随着土壤中Sb含量增加,头花蓼生物量及耐性系数减小,头花蓼各器官Sb含量增加,且表现为根＞叶＞茎。头花蓼根部、地上部对Sb的富集系数分别为0.53~1.76(平均1.32)、0.13~0.36(平均0.23),且均在土壤中Sb处理量为200 mg/kg时达到最大值；头花蓼对Sb的转运系数为0.13~0.24(平均0.18),表明头花蓼将Sb从根部转运到地上部的能力较低。在Sb浓度低于2.09 mg/kg的土壤中种植头花蓼,头花蓼根、茎、叶各部位均可安全食用；但土壤中Sb浓度高于8.72 mg/kg时,头花蓼各部位食用均存在安全风险。

Cumulative characteristics and health risk assessment of antimony in soil by Polygonum capitatum

To effectively control the heavy metal pollution of Polygonum capitatum and to ensure the safety of Polygonum capitatum medicinal use, the pot experiment was conducted. The absorption and accumulation of Sb of Polygonum capitatum and risk impacts of Sb in Polygonum capitatum on human health under different concentrations of antimony (Sb) contaminated soil were investigated. In addition, the safety limit of Sb in the soil for Polygonum capitatum was predicted. The results showed that with the increase of Sb content in the soil, the biomass and tolerance coefficient of Polygonum capitatum decreased, and the Sb content in various tissues of Polygonum capitatum increased in the order of root>leaf>stem. The enrichment coefficients of Sb in the roots and shoots of Polygonum capitatum were in the range of 0.53 to 1.76 (average 1.32) and 0.13 to 0.36 (average 0.23) respectively, which reached the maximum when the Sb treatment amount in the soil was 200 mg/kg. The transport coefficient of Polygonum capitatum to Sb is in the range of 0.13 to 0.24 (average 0.18), indicating that Polygonum capitatum has a low ability to transport Sb from the root to the ground. It is safe to eat roots, stems and leaves of Polygonum capitatum grown in soil with Sb concentration lower than 2.09 mg/kg. However, when Sb concentration in soil was higher than 8.72 mg/kg, there were safety risks in all parts of Polygonum capitatum.