Graduate Institute of Environmental Engineering, National Taiwan University, 1 Roosevelt Rd., Sec. 4, Da'an Dist., Taipei 10617, Taiwan.
Research Center for Environmental Changes, Academia Sinica, Building, No.128, Section 2, Academia Road, Nankang, Taipei 11529, Taiwan.
Environ Sci Technol. 2021 Sep 7;55(17):11805-11813. doi: 10.1021/acs.est.1c00706. Epub 2021 Aug 13.
This study focuses on estimating the probabilistic soil and dust ingestion rates for children under 3 years old by the Stochastic Human Exposure and Dose Simulation Soil and Dust (SHEDS-S/D) model developed by the U.S. Environmental Protection Agency. The health risk of children's exposure to heavy metals through soil and dust ingestion and dermal absorption was then assessed in three exposure scenarios. In the exposure scenario of direct contact with soil, the average soil and dust ingestion rates for children aged 24 to 36 months were 90.7 and 29.8 mg day in the sand and clay groups, respectively. Hand-to-mouth soil ingestion was identified as the main contributor to soil and dust ingestion rates, followed by hand-to-mouth dust ingestion and object-to-mouth dust ingestion. The soil-to-skin adherence factor was the most influential factor increasing the soil and dust ingestion rate based on a sensitivity analysis in the SHEDS-S/D model. Furthermore, the modeled soil and dust ingestion rates based on the SHEDS-S/D model were coincident with results calculated by the tracer element method. Our estimates highlight the soil ingestion rate as the key parameter increasing the risk for children, while a higher frequency of hand washing could potentially reduce the risk.
本研究旨在通过美国环境保护署开发的随机人体暴露与剂量模拟土壤和灰尘（SHEDS-S/D）模型来估算 3 岁以下儿童的土壤和灰尘摄入概率。然后，在三种暴露情景下评估了儿童通过土壤和灰尘摄入和皮肤吸收接触重金属的健康风险。在直接接触土壤的暴露情景中，24 至 36 个月大的儿童的平均土壤和灰尘摄入量在沙组和粘土地组中分别为 90.7 和 29.8mg/天。口含泥土被确定为导致土壤和灰尘摄入量的主要因素，其次是口含灰尘和物体到口含灰尘。土壤到皮肤附着因子是根据 SHEDS-S/D 模型中的敏感性分析增加土壤和灰尘摄入量的最具影响力的因素。此外，基于 SHEDS-S/D 模型的模型化土壤和灰尘摄入量与示踪元素法计算的结果一致。我们的估算结果突出了土壤摄入量作为增加儿童风险的关键参数，而增加洗手频率可能会降低风险。
