Lung function in oil spill responders 4-6 years after the Deepwater Horizon disaster

Oil spill response and clean-up (OSRC) workers were exposed to hazardous airborne chemicals following the 2010 Deepwater Horizon disaster. The aim of this study was to evaluate lung function in workers 4-6 years following the disaster using a prospective cohort. Participants who completed two spirometry test sessions 1-3 years, and 4-6 years after the spill (N = 1,838) were included and forced expiratory volume in 1 s (FEV₁; ml), forced vital capacity (FVC; ml), and ratio (FEV₁/FVC; %) determined. Linear mixed models were utilized to estimate relationships between OSRC exposures and lung function 4-6 years after the spill and changes since the prior measurement. Despite suggestive reduced lung function at 1-3 years, at the  4-6-year exam workers with total hydrocarbon (THC) exposure 1-2.99 ppm and ≥3 ppm compared to those with ≤0.29 ppm exhibited higher FEV₁ (β: 108 ml, 95% CI: 17, 198) and (β: 118 ml, 95% CI: 5, 232), respectively. Compared with support workers, those in higher exposed jobs displayed greater improvement in FEV₁ between visits: cleanup on water (β: 143 ml, 95% CI: 35, 250), operations (β: 132 ml, 95% CI: 30, 234) and response (β: 149 ml, 95% CI: 43, 256). Greater FEV₁ improvement was also associated with higher versus the lowest level THC exposure: 1-2.99 ppm (β: 134 ml, 95% CI: 57, 210) and ≥3 ppm (β: 205 ml, 95% CI: 109, 301). Lung function decrements seen shortly after the spill were no longer apparent 4-6 years later, with the greatest improvement among those with the highest exposures.