Duncan, South Carolina, USA 10 November 2017 -- (From news reports) -- Several people were hospitalized after firefighters responded Thursday to a report of a hazardous odor at Pratt Industries in Duncan.

Firefighters found a chemical off-gassing from containers at the recycling facility.

First responders did not immediately know what the chemical was.

Employees were evacuated and the Spartanburg County HAZMAT team responded to test the air and chemical.

David Probo with HAZMAT said they think a scale remover similar to a household chemical might have mixed with ammonia or another cleaning product and caused the off-gassing.

Seven people were taken to the hospital as a precaution for respiratory issues.

Firefighters don't think anyone is seriously injured.

Officials with the S.C. Department of Health and Environmental Control will monitor three canisters over the next few days.