On Sunday morning, as soon as she woke, Jessica Hulsey peeked outside her home in Houston's East End to see the impact of Hurricane Harvey. But it wasn't the rising water that surprised her.
"As soon as I opened the door, the smell hit my nose," she says.
At first she thought she may have left the gas can for her lawnmower out, because she says the smell was kind of like gasoline. But she hadn't. And, as it turns out, her neighbors say they smelled it, too.
"I was just asking myself, 'I wonder where this strong smell is coming from,'" she says.
Now she thinks she knows. The city of Houston is home to around 450 petrochemical plants, making it one of the biggest oil refining hubs in the world. Concern is growing that damage to some of these plants is polluting the air, and may threaten the water.
In Baytown, Texas, the storm damaged the roof of a large ExxonMobil refinery, which began emitting toxic chemicals.
"They have a limited amount of crew at the location because they want to minimize any safety concerns with their employees," Lettie Brysch, a public information officer for the city of Baytown, said on Tuesday.
A Chevron facility also flooded. And in the town of Crosby, Texas, floods knocked out power to the Arkema SA organic peroxide plant. Then the backup generators were flooded. That led to what the company calls a "serious" situation, because if the chemicals aren't properly refrigerated, they might explode. Tuesday, the company evacuated its employees, and nearby residents were also ordered to leave the area.
"It's not just that we have refineries or petrochemical facilities or boutique chemical plants ... we have everything," says Elena Craft, a toxicologist with the Environmental Defense Fund.
Local industry says it's doing everything it can to minimize any emissions caused by the storm. Exxon, Royal Dutch Shell and Petrobras are among those who shut down refineries as Harvey swept in, bringing down oil production in the Gulf of Mexico by nearly 20 percent.
But the EDF's Craft says the very act of shutting these plants down, and then re-starting them, actually produces pollution.
"An analogy would be like the cold start of a car. Where if you turn it off and then turn it back on," she says. "At least the older engines, it would take a while for the engines to heat up to the appropriate temperature to actually burn off some of the pollution."
The EDF and other groups are keeping track of regulatory filings petrochemical companies are required to make with the Texas Commission on Environment Quality. Right now, the groups estimate about a million pounds of toxic chemicals — many of them carcinogenic — will be released around Houston just as a result of the storm and floods.
"How many pounds of benzene or butadiene would you like to be exposed to?" Craft asks. "None!"
She says much of that pollution won't be released until after the waters recede and the factories and refineries get back online.