PDF(Pubmed)
Abstract：
Ethylene oxide (\"EtO\") is an industrially made volatile organic compound and a known human carcinogen. There are few reliable reports of ambient EtO concentrations around production and end-use facilities, however, despite major exposure concerns. We present in situ, fast (1 Hz), sensitive EtO measurements made during February 2023 across the southeastern Louisiana industrial corridor. We aggregated mobile data at 500 m spatial resolution and reported average mixing ratios for 75 km of the corridor. Mean and median aggregated values were 31.4 and 23.3 ppt, respectively, and a majority (75%) of 500 m grid cells were above 10.9 ppt, the lifetime exposure concentration corresponding to 100-in-one million excess cancer risk (1 × 10-4). A small subset (3.3%) were above 109 ppt (1000-in-one million cancer risk, 1 × 10-3); these tended to be near EtO-emitting facilities, though we observed plumes over 10 km from the nearest facilities. Many plumes were highly correlated with other measured gases, indicating potential emission sources, and a subset was measured simultaneously with a second commercial analyzer, showing good agreement. We estimated EtO for 13 census tracts, all of which were higher than EPA estimates (median difference of 21.3 ppt). Our findings provide important information about EtO concentrations and potential exposure risks in a key industrial region and advance the application of EtO analytical methods for ambient sampling and mobile monitoring for air toxics.
摘要：
环氧乙烷（“EtO”）是一种工业化生产的挥发性有机化合物，是一种已知的人类致癌物质。关于生产和最终用途设施周围的环境EtO浓度的可靠报告很少，然而,尽管存在重大风险。我们在原地展示，快速（1Hz），2023年2月在路易斯安那州东南部工业走廊进行了敏感的ETO测量。我们以500m的空间分辨率汇总了移动数据，并报告了走廊75km的平均混合比。平均值和中值合计值分别为31.4和23.3ppt，分别,大多数(75%)500米网格单元高于10.9ppt，终生暴露浓度对应于100万分之一的超额癌症风险（1×10-4）。一小部分（3.3％）高于109个百分点（100万分之一的癌症风险，1×10-3)；这些往往靠近EtO排放设施，尽管我们观察到距离最近设施超过10公里的羽流。许多羽流与其他测量气体高度相关，指示潜在的排放源，用第二个商用分析仪同时测量一个子集，表现出良好的协议。我们估计了13个人口普查区的EtO，所有这些都高于EPA的估计值（中位数差异为21.3ppt）。我们的发现提供了有关关键工业地区EtO浓度和潜在暴露风险的重要信息，并促进了EtO分析方法在环境采样和空气毒物移动监测中的应用。
