At least 2 dead and several injured when Texas Pemex plant leaks hydrogen sulfide

Deer Park, Texas – At least two workers at a Houston-area oil refinery died Thursday when hydrogen sulfide leaked into the plant, prompting urgent warnings for nearby residents to stay indoors before authorities later determined that the public was not in danger.

Nearly three dozen other people were taken to hospitals or treated at the scene, Harris County Sheriff Ed Gonzalez said. Hours after the leak began, Gonzalez said the area was still unsafe for investigators to enter and officials may not be able to enter until Friday.

The plant is operated by Pemex, Mexico’s state oil company, and is located in the suburb of Deer Park.

Gonzalez said the gas release occurred during work on a flange at the facility, which is part of a cluster of refineries and oil plants that make Houston the nation’s petrochemical hub.

Pemex said in a statement that investigations are ongoing and that operations have been “proactively stopped” at two units with the aim of mitigating the impact.

Local officials issued a shelter-in-place order at the site, but lifted it hours later after air monitoring showed no risk to the surrounding community, Deer Park Mayor Jerry Mouton said.

CBS Houston affiliate KHOU-TV Chief Meteorologist David Paul said the wind was calm Thursday night.

Hydrogen sulfide is a foul-smelling gas that can be toxic at high levels.

“Other than the smell, we’ve had no verifiable air monitoring to support that anything has gone outside the facility,” Mouton said.

Television news crews showed several ambulances and emergency vehicles at the scene. Gonzalez had originally posted on social media platform X that one person was airlifted to a hospital, but officials later said at a news conference that no one was airlifted.

The leak prompted the second shelter-in-place orders in Deer Park in a span of weeks. Last month, a pipe fire that burned for four days forced the evacuation of the surrounding neighborhoods.