Associations Between Oil Spill Exposure Patterns and Acute Symptoms in United States Coast Guard Responders During the Deepwater Horizon Response

Background: Oil spill response workers encounter a unique mixture of hazardous exposures. Few studies have attempted to model these mixtures and evaluate the impact on worker health. The purpose of this investigation was to understand the association between clustered patterns of hazardous exposure and acute symptoms reported by United States Coast Guard (USCG) responders during the Deepwater Horizon oil spill (DWHOS). Methods: We conducted a cross-sectional study of USCG members who responded to the DWHOS and completed a post-deployment survey (n = 4855). The survey asked responders about a variety of hazardous exposures and acute symptoms experienced during their deployment. A previously-conducted latent class analysis identified four unique latent classes (LC) which represent reported exposure patterns within this study population. We utilized the three higher LC levels to represent increasing probabilities of exposures to crude oil, exhaust, general outdoor environment, and experience of anxiety, with a “low overall exposure” group acting as the reference. For the present analysis, participants were assigned their most probable LC. Using multivariable log-binomial regression analyses, adjusted prevalence ratios (aPR) of acute symptoms in each most probable LC compared to the reference LC were estimated. Results: There were significant positive associations between most probable LCs and acute symptoms in all major organ systems with evidence of exposure−response relationships. Some of the strongest associations for individual acute symptoms representative of each organ system included chest pain, skin rash/itching, difficulty hearing, diarrhea, muscle pain, lightheadedness/dizziness, and shortness of breath. Conclusions: This study broadens the current understanding of oil spill response work hazards by focusing on a more holistic exposure assessment, modeled by most probable LC-derived exposure patterns.