Four employees of a north Phoenix recycling and trash facility reported feeling ill Tuesday morning and Phoenix firefighters were trying to determine whether they were exposed to a possible chemical.
Fire Capt. Larry Nunez said the workers suffered from symptoms that included scratchy throats, chest pain and vomiting.
None of the workers appeared to be critically ill or required hospitalization, Nunez said.
Firefighters hadn't determined a chemical that might be involved or whether it was already stored at the facility or part of the recycling, Nunez said.
He said a hazardous-materials crew is at the site to evaluate the situation.
No other information was immediately available.
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