食用百合-土壤体系中镉、铅和汞的潜在生态和健康风险

采用潜在生态危害指数法和靶标危害系数法对甘肃省传统食用百合产区食用百合-土壤中重金属镉（Cd）、铅（Pb）和汞（Hg）进行潜在生态和健康风险分析。结果表明：与1993年甘肃省土壤重金属背景值相比，种植食用百合的土壤中Cd、Pb和Hg含量有明显增加现象，分别提高了1.82、0.27、1.71 倍，但符合绿色食品环境质量标准；以NY/T 391-2013《绿色食品 产地环境质量》作为参比值，研究区域食用百合土壤重金属Cd、Pb和Hg的平均单项潜在生态风险指数分别为18.25、2.78、5.19，均小于40，风险级别为A级，生态危害程度较低；以1993年甘肃省土壤环境重金属背景值为参照值评价，百合土壤潜在生态危害程度顺序是Cd＞Hg＞Pb，对研究区域生态环境具有潜在影响的主要是镉，综合潜在生态危害程度为B级，属于中等水平；食用百合Cd、Pb和Hg的生物富集系数分别为0.131、0.003和0.022；食用百合Cd、Pb和Hg的靶标危害系数，即食用风险值低于1，重金属未超标的百合不会对人体健康构成危害。

Potential Health and Ecological Risks of Accumulation of Cadmium,Lead and Mercury in Soil-Edible Lily Systems

In this study, the potential ecological and health risks of the heavy metals cadmium (Cd), lead (Pb) and mercury
(Hg) in edible lily and its growing soil in Gansu province were analyzed by using the potential ecological risk index method
and target hazard quotient (THQ) method. The results showed that the contents of heavy metals in edible lily-growing
soil were significantly increased by 1.82, 0.27 and 1.71 times compared with the background values of soil heavy metals
in Gansu province in 1993, respectively, which were still in line with environmental quality standards for green foods.
According to the Environmental Quality for Green Food Producing Area (NY/T 391-2013), the average individual potential
ecological risk indices of Cd, Pb and Hg in edible lily-growing soil were 18.25, 2.78 and 5.19, respectively. All these risk
indices were less than 40, suggesting that the risk was at level A and the degree of ecological harm was relatively low.
Taking the background values of soil heavy metals in Gansu province in 1993 as reference, the order of degree of potential
ecological hazard in soil was Cd > Hg > Pb. Cadmium had a potential impact on the ecological environment of all producing
areas investigated. The comprehensive potential ecological hazard level was level B, which belonged to the medium level.
The biological enrichment coefficients of Cd, Pb and Hg in edible lily were 0.131, 0.003 and 0.022, respectively. The THQ
value of cadmium, lead and mercury was lower than 1. Heavy metal levels of lily did not exceed the maximum allowable
limit and thereby was not hazardous to human health.