UNION COUNTY, N.C. -- The Union County Health Department and DSS building is closed Thursday.
The county's public information officer, Brett Vines, tells NBC Charlotte that employees began complaining of headaches, nausea, dizziness and vomiting in the morning. Eleven of them were sent to CMC Union.
Other workers were sent home.
Employees reported a strong odor. Investigators are working to determine the source. Two big grease bins were found in a dumpster behind another business near the air handling system.
A sign outside of the building says it will reopen on Friday.