Abstract: The incidences of heavy metals in contaminated soil are emerging a high and multiple periods.Besides,the bioavailability of heavy metals is decreasing with aging time of the soil,and potential environmental risk of their contamination will correspondingly be declining.In vitro methods can effectively indicate the bioavailability of heavy metals,and significantly cut down the conservativeness of health risk assessment results based on the total exposure dose that is the total concentrations of heavy metals.The in vitro methods have been applied to assess the health risk of heavy metals in aged soils,and have been of great concern.In this paper,the bioaccessibility of heavy metals was defined.The test methods were summed up,and the main factors were also quantitatively clarified,which mainly include in vitro parameters,soil physical and chemical properties and characteristics of heavy metals and so on.In addition,the bioaccessibility of heavy metals applied in health risk assessment were discussed.Finally,the summary of current challenges and the prospectof further studies in the field have been raised.The purpose of this article is to provide the theoretical support for contaminated sites in the risk source identification,repair target determination and management countermeasures screening.

Key words: aged soils, heavy metals, in vitro methods, bioaccessibility, health risk assessment

摘要： 目前，土壤重金属污染事件进入高发期和多发期，同时，随着土壤老化时间的延长，重金属的生物有效性不断降低，其潜在污染环境风险也相应地下降。体外胃肠模拟法（in vitro）能有效指示重金属的人体可给量，可显著降低基于总量为暴露剂量的健康风险评估结果的保守性，因而被应用于评估老化土壤中重金属的人体健康风险，且已深受关注。本文定义了重金属的人体可给性、归纳了其测试方法（PBET、SBET和UBM等），并定量阐明了其主要影响因素，主要包括in vitro参数、土壤理化性质和重金属自身的特性等；然后，论述了重金属人体可给性在健康风险评价的应用。最后，对该领域当前存在的问题和今后的研究方向进行了总结和展望，旨在为污染场地风险源识别、修复目标确定及管理对策筛选提供理论支撑。

关键词: 老化土壤, 重金属, 体外胃肠模拟法, 人体可给性, 健康风险评价