A shelter-in-place advisory was issued on Thursday for thousands of residents living in Houston suburbs after a petrochemical fire at a nearby gasoline-production facility released dangerous levels of the toxic chemical benzene.

The fire at the Intercontinental Terminals Company (ITC) facility in La Porte was extinguished after blazing for four days, from Sunday to Wednesday. There was a one-day shelter-in-place issued on Sunday, but between then up until Thursday’s advisory, ITC claimed that toxic chemical levels were “below levels that would represent a public health concern.”

Benzene is a toxic chemical that has been linked to leukemia in humans after long-term exposure to high levels in the air, according to the Centers for Disease Control and Prevention (CDC). Short-term health effects of benzene inhalation include “drowsiness, dizziness, headaches, tremors, confusion, and/or unconsciousness,” according to the CDC. Benzene liquid or vapor exposure can irritate the eyes and throat, and cause redness and blisters on the skin.

Eight schools and four college campuses in Houston suburbs such as Deer Park, Pasadena, La Porte, as well as a fifteen mile stretch of Texas Highway 225, have also been closed in order to abide by the shelter-in-place advisory.

It’s unclear how long the ITC and government groups will monitor the region for air quality, or whether the long-term health effects on residents will be measured. Representatives from the Deer Park Police Department, the CDC—who are all responding to the crisis, according to ITC—did not return Motherboard's requests for comment.

In an email to Motherboard, an ITC representative said that the exact cause of the fire is still under investigation. The Texas Commission on Environmental Quality referred Motherboard to a press release that said the Environmental Protection Agency is using specialized trucks and planes to monitor air quality in the area.

Mary Johnson, a Deer Park resident, told local news outlet K-Houston 11 (K-Hou) on Wednesday hat she had been feeling sick for three days, since the fire started. Johnson lives just a few miles from ITC facilities. Johnson’s husband had to go to the doctor, and Johnson claimed that she suffered from headaches and had trouble breathing.

"I was nauseated," Johnson said to K-Hou. "My throat was hurting. My ears were hurting. My eyes were running water and my nose was like a faucet."

Other local residents have also expressed concerns about the air quality on Twitter.

A March 18 press release from ITC says that “claims have arisen as a result of the Sunday morning incident,” and instructs anyone who has suffered damage or loss to fill out a form on their website.

Dirty-fuel facilities are notoriously dangerous for workers, and for residents who live near them.

In December, an explosion at a Con Edison facility in Astoria, Queens in New York killed power for thousands of residents for hours, and lit up the New York City sky a strange shade of aqua-blue. It’s unclear exactly which combination of chemicals caused the sky to appear aqua-blue.

Environmental policy experts have recommended that we make natural gas and electric utilities public, which could give local residents the power to make these utilities switch to safer, more sustainable forms of energy like solar and wind. It would also give people the power to organize the utilities’ management structure, and set the rates they have to pay for gas and power.

As of December 2018, a majority of registered voters think that the US should do what it has to do to reduce greenhouse gas emissions. But private companies have no incentive to compromise their profit margins for health and safety of citizens. And don’t just look to companies like ITC—look to companies like Amazon, Google, and Microsoft.

A recent Gizmodo report found that these companies are all lending computing services to oil and gas companies in order to streamline their operations and maximize these companies’ profits.

Perhaps nationalization of gas and electric utilities could happen in the Green New Deal. But for now, petrochemical facilities continue to be an unsafe way for Americans to get their power. The benzene leak in Texas is a grim example.