BAYTOWN, Texas (KTRK) -- The shelter in place following the ExxonMobil plant fire may have been lifted at 3 p.m. Wednesday afternoon, but you should still pay attention over the next couple of days as what went into the air settles back to earth.
Exxon, Harris County and the city of Baytown all say they're monitoring air quality and that there are no current concerns.
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What burned, as we've reported, was a propylene recovery unit containing both a light hydrocarbon mixture and propane.
Exxon assured the community there were no detectible levels in the air or adverse impact to the environment.
But Dr. Noreen Khan-Mayberry, an environmental toxicologist known as the Tox Doc, told Eyewitness News that it's important the check the air and the water during and after a chemical fire because what goes up must come down.
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"It's going to come down somewhere. Either the wind is going to push it somewhere else and it's going to fall somewhere else. It's going to dissipate and fall. Or it will fall in the same area," Dr. Khan-Mayberry said. "So that's something to keep in mind. That's why I always ask about wind patterns. How are we looking in wind patterns?"
She says the chemicals can persist and they can be very persistent.
"So we have to test the water," Dr. Khan-Mayberry said.
The Texas Commission on Environmental Quality has fixed site monitors nearby. Harris County added mobile monitors a half hour after the fire started burning.
The latest numbers from the county, recorded around 4 p.m. Wednesday, showed no environmental impact.
You can see more at the Harris County Pollution Control Services Department website.
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