Department of Epidemiology and Biostatistics, WVU School of Public Health, West Virginia University, One Medical Center Drive, Morgantown, WV 26506, USA.
Department of Biostatistics, UCLA Fielding School of Public Health, University of California-Los Angeles, 650 Charles E. Young Drive, Los Angeles, CA 90095, USA.
Ann Work Expo Health. 2022 Apr 7;66(Suppl 1):i140-i155. doi: 10.1093/annweh/wxab038.
The NIEHS GuLF STUDY is an epidemiologic study of the health of workers who participated in the 2010 Deepwater Horizon oil spill response and clean-up effort. Even with a large database of approximately 28 000 personal samples that were analyzed for total hydrocarbons (THCs) and other oil-related chemicals, resulting in nearly 160 000 full-shift personal measurements, there were still exposure scenarios where the number of measurements was too limited to rigorously assess exposures. Also available were over 26 million volatile organic compounds (VOCs) area air measurements of approximately 1-min duration, collected from direct-reading instruments on 38 large vessels generally located near the leaking well. This paper presents a strategy for converting the VOC database into hourly average air concentrations by vessel as the first step of a larger process designed to use these data to supplement full-shift THC personal exposure measurements. We applied a Bayesian method to account for measurements with values below the analytic instrument's limit of detection while processing the large database into average instrument-hour concentrations and then hourly concentrations across instruments on each day of measurement on each of the vessels. To illustrate this process, we present results on the drilling rig ship, the Discoverer Enterprise. The methods reduced the 26 million measurements to 21 900 hourly averages, which later contributed to the development of additional full-shift THC observations. The approach used here can be applied by occupational health professionals with large datasets of direct-reading instruments to better understand workplace exposures.
NIEHS 墨西哥湾研究是一项针对参与 2010 年深海地平线石油泄漏应对和清理工作的工人健康状况的流行病学研究。即使有大约 28000 份个人样本的大型数据库进行了总碳氢化合物（THCs）和其他与石油相关的化学物质分析，产生了近 160000 次完整轮班的个人测量值，仍然存在暴露情况，其中测量值的数量非常有限，无法严格评估暴露情况。此外，还有超过 2600 万个挥发性有机化合物（VOCs）的区域空气测量值，持续时间约为 1 分钟，这些测量值是从位于泄漏井附近的 38 艘大型船只上的直读仪器上收集的。本文提出了一种将 VOC 数据库转换为每小时平均空气浓度的策略，作为一个更大的过程的第一步，该过程旨在使用这些数据来补充完整轮班 THC 个人暴露测量值。我们应用贝叶斯方法来处理大型数据库中的平均仪器小时浓度和每个船只每天测量的每个仪器的小时浓度，以解决分析仪器检测限以下的测量值。为了说明这个过程，我们展示了在钻井平台船“发现者企业号”上的结果。该方法将 2600 万次测量值减少到 21900 次每小时平均值，这些平均值后来为进一步开发完整轮班 THC 观察值做出了贡献。职业健康专业人员可以使用大型直读仪器数据集应用这里使用的方法来更好地了解工作场所暴露情况。
