Abstract:
|
In 2010, the Deepwater Horizon oil rig exploded, resulting in the release of over four million barrels of oil into the Gulf of Mexico over the ensuing three months. The Gulf STUDY is an epidemiological study investigating potential adverse health effects in workers who participated in the oil spill response and clean-up. Our goal is to estimate exposures to benzene, ethylbenzene, toluene, xylene (BTEX), total hydrocarbons (THC), and hexane in specific clean-up jobs for later use in a GuLF STUDY job-exposure matrix. Although over 25,000 air samples were collected during the spill, for many jobs a large percentage of measurements were below the analytic methods' limit of detection. Here we use THC, a composite of the volatile components of oil with a lower degree of censoring, to develop linear models for estimating BTEX and hexane air concentrations. A novel Bayesian hierarchical linear model allows us to model exposures for multiple jobs simultaneously while accounting for censoring in both THC and the chemical of interest. We illustrate the methodology by estimating exposures for job-groups on the Development Driller III, a vessel charged with drilling one of the relief wells.
|
ASA Meetings Department
732 North Washington Street, Alexandria, VA 22314
(703) 684-1221 • meetings@amstat.org
Copyright © American Statistical Association.