University of Michigan, Department of Environmental Health Sciences, Ann Arbor, MI, USA.
University of Michigan, Department of Environmental Health Sciences, Ann Arbor, MI, USA.
Sci Total Environ. 2020 Jun 20;722:137891. doi: 10.1016/j.scitotenv.2020.137891. Epub 2020 Mar 21.
Many cities are revitalizing their urban cores through the demolition of abandoned residential dwellings (ARDs). However, data regarding the emissions of asbestos during such an operation are sparse. We measured airborne asbestos emissions from emergency demolitions (demolitions on structures deemed too dangerous to enter and remove asbestos) of ARDs in Detroit. High-flow air sampling was conducted during ARD demolitions. Air samples were analyzed using Phased Contrast Microscopy (PCM), and a subset using Transmission Electron Microscopy (TEM). One hundred and one air samples were collected on 25 emergency demolitions. Fifty-four of the 101 PCM samples (53%) exceeded the limit of detection (LOD). However, only 2 of 46 TEM samples (4%) exceeded the LOD for asbestos; these latter samples were from two different demolitions and each contained a single chrysotile asbestos fiber. Using conservative exposure assumptions and commonly-accepted risk estimation formulae, we estimated the lifetime risk of mesothelioma and lung cancer combined to be less than one case per one million people. Emissions of airborne asbestos during emergency (unabated) ARD demolition operations appear to be negligible. As a result, the associated health risk for asbestos-related disease is also negligible. Reconsideration of current regulatory mandates for asbestos abatement in ARDs may be warranted.
许多城市通过拆除废弃住宅(ARD)来振兴城市中心。然而,关于此类操作中石棉排放的数据却很少。我们测量了底特律紧急拆除 ARD 时空气中的石棉排放。在 ARD 拆除过程中进行了高流量空气采样。使用相衬显微镜(PCM)和透射电子显微镜(TEM)的子集对空气样本进行了分析。在 25 次紧急拆除中收集了 101 个空气样本。101 个 PCM 样本中有 54 个(53%)超过了检测限(LOD)。然而,只有 46 个 TEM 样本中的 2 个(4%)超过了石棉的 LOD;这两个样本来自两个不同的拆除现场,每个样本中都含有一根单一的温石棉纤维。根据保守的暴露假设和常用的风险估计公式,我们估计一生中因接触石棉而患间皮瘤和肺癌的综合风险低于每百万人中一例。在紧急(未抑制)ARD 拆除作业中,空气中石棉的排放似乎可以忽略不计。因此,与石棉相关疾病的相关健康风险也可以忽略不计。可能需要重新考虑当前 ARD 中石棉清除的法规要求。