不同类型施工降尘中重金属污染特征及健康风险评价

为了解北京市建筑施工降尘中重金属的污染特征及存在的健康风险，分别选择建筑物拆迁及主体建设两个研究区，共收集大气降尘样品25份，使用微波消解-电感耦合等离子体质谱法（ICP-MS）测试了样品中8种重金属的质量分数.结果表明：Zn、Mn、Cu、Pb、Cr、Ni、Cd在建筑物拆迁降尘中的平均含量高于建筑主体建设降尘.建筑物拆迁降尘中Zn、Cr、Pb、Ni的扩散趋势与采样期间的主导风向一致；建筑主体建设降尘中Zn、Mn、Cr、Pb、Ni、As的高值区均出现在主体建设中心附近，并且有沿场地中心向四周扩散的趋势.健康风险评价结果表明，两个研究区内Zn、Mn、Cu、Pb经手-口、皮肤、呼吸3种暴露途径下的总非致癌风险对儿童的健康构成了威胁；手-口途径摄入是引起成年男性、成年女性、儿童等3类人群非致癌风险的主要暴露途径.无论是建筑物拆迁研究区还是主体建设研究区，降尘中致癌重金属Cr、As、Ni、Cd对人体的致癌健康风险均呈现出TCR（成年男性）>TCR（成年女性）>TCR（儿童）的规律，并且对3类人群构成的致癌风险均在可接受范围内.

Heavy metal pollution characteristics and associated health risk assessment in different types of construction dust

A total of 25 dust fall samples were collected in both study areas of building demolition site and main construction site to analyze the pollution characteristics of heavy metals in the construction fugitive dust in Beijing and its associated health risk. The content of 8 heavy metals including Zn, Mn, Cu, Pb, Cr, Ni, As, and Cd in the samples were measured by using inductively couple plasma-mass spectrometry (ICP-MS). The results showed that the average contents of Zn, Mn, Cu, Pb, Cr, Ni and Cd in the building demolition dust were higher than those in the main building construction dust. The diffusion trend of Zn, Cr, Pb and Ni in the building demolition dust was consistent with the dominant wind direction during the sampling period. The greatest contents of Zn, Mn, Cr, Pb, Ni and As of the main building construction dust were found close to the center of the main construction area, with the contents of metals diffusing from the center to surrounding areas. The results of health risk assessment showed that the total non-carcinogenic risk of Zn, Mn, Cu and Pb posed a threat to children's health via all three exposure routes-ingestion, dermal, and inhalation in both study areas. Ingestion exposure was the main exposure route of the non-carcinogenic risk for adult male, adult female and children. The carcinogenic health risks of Cr, As, Ni and Cd in dustfall followed a descending order of TCR (adult male) > TCR (adult female) > TCR (children), and the carcinogenic risks to all three groups were acceptable.