Hazardous materials crews are investigating the source of noxious fumes and a powder near the Del Mar Fairgrounds that sent several workers to a hospital, according to firefighters.
Three men were working beneath the Hilton San Diego/Del Mar hotel on Jimmy Durante Boulevard when they started having trouble breathing at about 9:40 a.m. on Thursday, San Diego Fire-Rescue spokesperson Maurice Luque said.
When they emerged from the building the workers complained of burning eyes and lungs. One of the men vomited. They were all covered in a white powder.
The workers were decontaminated and taken to a local hospital. An emergency medical technician was also decontaminated.
The powder could have been lime and the fumes may have been sewer gas, Luque said.
Crews were testing the site beneath the hotel. The process was expected to take several hours.
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