兰州市菜地土壤和蔬菜镉含量及其健康风险分析

在兰州市及周区共采集65个土壤样品和46种155个蔬菜样品,用石墨炉-原子吸收分光光度法测定样品中的镉含量,对兰州市蔬菜和菜地土壤镉含量状况进行调查.结果表明:兰州市菜地土壤镉积累明显,其范围为0.11~0.72 mg.kg-1,平均值为0.22 mg.kg-1,变异系数为61.93%;土样之间存在较大的变异性,反映了人为活动已对土壤中镉含量产生了明显的影响.兰州市蔬菜镉含量范围、平均值和变异系数分别为1.2~76.0μg.kg-1、14.01μg.kg-1和30.3%;叶菜类和葱蒜类蔬菜的镉平均含量显著高于茄果类和根茎类.兰州市居民人均从蔬菜中摄入镉的量为19.6μg.d-1,部分蔬菜镉可能给食用者带来一定的潜在健康风险.

Cadmium concentrations in vegetables and soils in Lanzhou City and its potential risk to human health

A large scale survey of cadmium levels in soil and vegetables planted or sold in Lanzhou was conducted. A total of 65 soil samples and 155 fresh vegetable samples of 46 cultivars were collected. Cadmium concentrations of the samples were measured using graphite furnace atomic absorption spectrometry (GF-AAS). The results showed as follows: cadmium concentrations in soils ranged from 0.11 mg·kg~(-1) to 0.72 mg·kg~(-1), the average value was 0.22 mg·kg~(-1) , and the coefficient of variation was 61.93 %, so the cadmium concentration among samples were much different, this indicated that human activities obviously effected the cadmium concentration in soil. Cadmium concentrations in the edible plant portions ranged from 1.2 μg·kg~(-1) to 76.0 μg·kg~(-1) fresh weight, the average value was 14.01 μg·kg~(-1),and the coefficient of variation was 30.3 %. The cadmium concentration of leaf vegetables and bulb crops were both significantly higher than selanageous fruits and root vegetables. The average cadmium ingestion rate of civilians in Lanzhou was 19.6 μg·d~(-1). Some cadmium ingestion brought potential health risk to local residents.