DALLAS (CBSDFW.COM) – A reported spill of a package of Carbolic acid at the USPS Bulk Mail Center in Dallas lead to four people being taken to area hospitals.

Carbolic acid is used in plastics.

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It happened around 12:30 p.m. Thursday at the center at 2400 D-FW Turnpike Service Road.

Hazmat Bulk Mail Center in Dallas (Chopper11)

The building was evacuated before Dallas Fire-Rescue crews arrived on scene.

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The four victims inhaled vapors from the acid.

Their conditions are not known at this time.

Hazmat Bulk Mail Center in Dallas (Chopper11)

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