中文摘要：

为了研究土壤中镉生物可给性与土壤属性之间的相互关系以及人体无意摄入土壤镉的风险，采集我国一些地区的16个土壤样品，利用invitro方法研究了这些土壤中镉的生物可给性及其对人体的健康风险．结果表明，有11个土壤样品中镉的含量高过我国土壤环境质量标准的三级标准；土壤中镉的溶解态浓度及其生物可给性变化很大，模拟胃和小肠液中镉的溶解态含量分别为0．05～20．71mg·kg^-1和0．03～11．99mg·kg^-1，平均值分别为1．81mg·kg^-1和1．06mg·kg^-1；模拟胃和小肠液中镉的生物可给性分别为6．37％-69．43％和3．19％～36．91％，平均值分别为25．34％和14．84％．模拟胃液中镉的溶解态含量与土壤pH有显著的相关性．如以胃阶段为判断，无意摄人土壤中镉对儿童的PTWI贡献率除广西南宁的土壤为26．90％外，其它有11个土壤样品低于1．00％．如以小肠阶段为判断，无意摄人土壤中镉对儿童的PTWI贡献率最高为广西南宁的土壤达15．57％，另有4个土壤样品高于1．00％，其它都低于1．00％．可见，对于本研究中大多数土壤，通过13部无意摄入土壤中镉的对人体并没有很高的风险．但当土壤中镉含量较高，同时其具有很高的生物可给性，就会对人体健康产生很大的风险．

英文摘要：

Sixteen soil samples were collected from different sites of China to study the bioaccessibility of soil cadmium. The relationship between the soil properties and the bioaceessibility as well as the health risk assessment of the oral ingestion soil was also studied. The results showed that comparing with Chinese environmental quality standard for soils, the concentrations of cadmium in 11 soil samples were higher than the standard. The high variability of dissolved and bioaccessible cadmium of soils were observed. Concentrations of bioaccessible Cd ranged from 0. 05-20.71 mg · kg^-1 and 0.03-11.99 mg· kg^-1 with a mean of 1.81 mg · kg^-1and 1.06 mg · kg^-1 in gastric and small intestinal phase respectively. Bioaecessible Cd ranged from 6. 37% -69.43% and 3.19% -36.91% with a mean of 25.34% and 14. 84% in gastric and small intestinal phase respectively. A significant correlation between dissolved cadmium in gastric stage with the soil pH was also observed. In gastric stage, for children, the highest contribution of the oral ingestion soil cadmium to the provisional tolerable weekly intake （PTWI） that recommended by WHO was 26. 90% in the soil sample that was collected from Nanning Guangxi and the contribution rate in 11 soil samples is lower than 1.00%. In small intestinal stage, for children, the contribution of the oral ingestion soil cadmium to PTWI was also variable. The highest contribution rate was 15.57% , the four samples were higher than 1.00% and others were below 1.00% . Health risk from the oral ingestion of soil cadmium was low in most of soils and the high health risk only occurred in the soil sample with high total cadmium concentration and high bioaccessibility.