On May 28, 2010, the National Institute for Occupational Safety and Health (NIOSH) received a request for a health hazard evaluation (HHE) from BP management concerning health effects experienced by responders to the oil release.

The request was prompted by the May 26, 2010, hospitalization of seven fishermen who were working in BP’s Vessels of Opportunity (VoO) program in the Gulf of Mexico. The fishermen had been hospitalized for symptoms that were initially believed to be related to exposures experienced during their response activities, particularly booming and skimming oil.