Shao Yuan, Almberg Kirsten S, Friedman Lee S, Cohen Robert A, Go Leonard H T
School of Public Health, Division of Environmental and Occupational Health Sciences, University of Illinois Chicago, Chicago, Illinois, USA
School of Public Health, Division of Environmental and Occupational Health Sciences, University of Illinois Chicago, Chicago, Illinois, USA.
Occup Environ Med. 2025 Feb 12;81(12):622-627. doi: 10.1136/oemed-2024-109689.
Previous studies suggest respirable crystalline silica (RCS) is an important driver of resurgent pneumoconiosis among US coal miners. Although greater attention has been focused on dust exposures in underground coal miners, surface miners are also at risk of severe disease. This study explores RCS exposure in this population.
We analysed 91 950 respirable quartz samples from 4127 US surface coal mines from 1982 to 2023. We calculated the geometric mean of respirable quartz concentration for each mine-year combination. Then, for each calendar year, we averaged the geometric means across all mines. We used generalised estimating equation models with a natural logarithm link function and Poisson distribution to evaluate the marginal effects of mine characteristic variables on the mass concentration of respirable quartz based on individual dust sample results.
Drillers and bulldozer operators had annual mean respirable quartz exposures as high as 0.58 and 0.32 mg/m3, respectively, while other occupations combined had exposure of 0.08 mg/m. The mean mine-level respirable quartz mass concentrations decreased substantially over time for all three occupation groups. Drillers or bulldozer operators, mine location in Central Appalachia and lack of a mine safety committee were predictive of higher respirable quartz mass concentrations.
These data demonstrate exceptionally high RCS overexposures among certain groups of surface coal miners, particularly drillers and bulldozer operators in the 1980s and 1990s. Despite recent improvement in RCS levels, these data underscore the importance of continued medical surveillance of current and former surface coal miners.
先前的研究表明，可吸入结晶二氧化硅（RCS）是美国煤矿工人复发性尘肺病的一个重要驱动因素。尽管更多的注意力集中在地下煤矿工人的粉尘暴露上，但露天煤矿工人也有患严重疾病的风险。本研究探讨了该人群中的RCS暴露情况。
我们分析了1982年至2023年期间来自美国4127个露天煤矿的91950份可吸入石英样本。我们计算了每个矿井-年份组合的可吸入石英浓度的几何平均值。然后，对于每个日历年，我们对所有矿井的几何平均值进行了平均。我们使用具有自然对数链接函数和泊松分布的广义估计方程模型，根据个体粉尘样本结果评估矿井特征变量对可吸入石英质量浓度的边际效应。
钻机操作员和推土机操作员的年度平均可吸入石英暴露量分别高达0.58和0.32毫克/立方米，而其他职业的组合暴露量为0.08毫克/立方米。所有三个职业组的矿井级可吸入石英质量浓度随时间大幅下降。钻机操作员或推土机操作员、位于阿巴拉契亚中部的矿井以及缺乏矿井安全委员会是可吸入石英质量浓度较高的预测因素。
这些数据表明，某些露天煤矿工人群体，特别是20世纪80年代和90年代的钻机操作员和推土机操作员，存在极高的RCS过度暴露情况。尽管最近RCS水平有所改善，但这些数据强调了对当前和以前的露天煤矿工人持续进行医学监测的重要性。
