POINT COMFORT, Texas – A South Texas man has died after inhaling hydrogen fluoride gas while working in the chemical department of an Alcoa plant.

Alcoa officials identified the man Wednesday as John Dorton, 37, of Port Lavaca. Dorton came in contact with the gas Tuesday while working in the area of the plant that makes aluminum fluoride, which is used in the production of aluminum, according to a news release.

“It’s a very sad day for us here,” said Laurel Cahill, Alcoa’s director of communications.

Alcoa has begun an investigation and inspectors from the U.S. Department of Labor’s Mine Safety and Health Administration were at the plant Wednesday afternoon.

The preliminary investigation indicates that the exposure happened at 2 p.m. Tuesday as Dorton worked near a valve, Amy Louviere, a spokeswoman for the administration, said in a story for Thursday’s Victoria Advocate.

Dorton was pronounced dead seven hours later at Memorial Hermann Hospital in Houston, where he was taken by air ambulance after being treated at a Victoria hospital.

Louviere said the area where the accident happened is shut down while all other areas remain in operation.

Alcoa is based in Pittsburgh, Pa.