Deadly refinery leak adds to US toxic accident toll

By Dana Drugmand

A Texas oil refinery with a history of environmental violations was the site of a deadly hydrogen sulfide leak last week, killing two people and injuring more than two dozen others and adding to a long list of US industrial accidents US regulators say they are trying to rein in.

The chemical release is also the latest accident at the Houston refinery. The facility has  been cited for nearly 2,000 environmental violations over the past decade. 

Located in Deer Park, Texas along the Houston Ship channel, the 1500-acre refinery complex is owned by the Mexican oil company PEMEX, which took over full ownership of the facility from Shell in 2021. 

The incident at the refinery, which occurred on the afternoon of October 10, killed two PEMEX employees, and at least 35 others were treated on the scene or transported for further medical attention, according to officials. 

Hydrogen sulfide is a colorless, extremely flammable, highly toxic gas that gives off a rotten egg odor. Exposure at lower concentrations can cause headaches, dizziness, nausea, irritation of the eyes, throat and respiratory tract and loss of smell, and acute exposure at high concentrations can result in unconsciousness and even death. 

“Unfortunately, Texas has a poor track record of forcing petrochemical facilities to take safety and compliance seriously,” Luke Metzger, executive director of Environment Texas, said in a statement. “It makes me wonder if this awful incident could have been prevented.” 

A “comprehensive investigation” is needed, he said.

Accidental chemical releases have become common occurrences across the US, with some data showing these incidents happen almost daily in some form or another. 

Last year, the EPA proposed several changes to regulations that apply to sites dealing with hazardous chemicals but industrial users have pushed back on new requirements.

The Deer Park facility has a history of noncompliance with environmental and permit regulations, racking up over $1.6 million in regulatory fines since 2012 and 1,946 environmental violations over the past decade, Oil and Gas Watch reported last year. A fire broke out at the plant in May 2023 that sent plumes of black smoke into nearby neighborhoods. 

Last week’s hydrogen sulfide leak underscores the risk that chemical facilities pose to workers and the surrounding communities, environmental advocates warned. 

PEMEX did not immediately respond to a request for comment.