Following the Deepwater Horizon (DWH) disaster, BP requested that NIOSH evaluate exposures and health effects among workers involved in response activities. NIOSH began in early May by developing a roster of more than 50,000 potential workers. Then NIOSH activities were focused on exposure and health assessment at specific worksites. These included on-shore evaluations (shore clean-up, wildlife rehabilitation, equipment decontamination, and waste stream management) and off-shore evaluations (source control, in-situ burns, and booming/skimming/dispersant operations). Nine interim reports (https://www.cdc.gov/niosh/topics/oilspillresponse/gulfspillhhe.html
) have been released, including: 1) industrial hygiene surveys, symptom surveys, and medical interviews during small-area oil dispersant missions on two vessels; 2) infirmary logs for response workers: gastrointestinal, dermatological, respiratory, ophthalmic, and dental symptoms; injuries, bites and stings; heat-related disorders; and other conditions; 3) industrial hygiene activities aboard a vessel during an oil skimming mission; 4) measurement of airborne concentrations of benzene, 2-butoxyethanol, and CO on several vessels dispersing foam patches on the water; 5) exposure assessment, site characterization, and symptoms assessment among wildlife cleaning workers; 6) comparison symptoms among offshore workers to those among shore workers not having oil, dispersant, or cleaning material exposures; 7) exposure assessment and symptom questionnaire at 67 shore-cleaning worksites; 8) health hazards at equipment and boat repair/decontamination and waste management worksites; 9) laboratory analysis of various bulk samples: fresh and weathered oil and burnt oil residue, dispersant foam, and drilling mud. Principal NIOSH recommendations related to worker training, use of personal protective equipment, heat stress management, and proactive reporting of illness/injury.