GRAND PRAIRIE, Texas (CBSDFW.COM) – Even with the flames from the Poly-America fire nearly out, doctors are urging those in nearby neighborhoods to stay inside.

The flames were visible from miles away for hours.

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“We saw the explosion when we were getting on the highway,” says Jennifer Borel. Borel says she has medical training so initially hurried to the area to see if anyone needed help. “A huge wave of heat– there were people running through the fields. I was just making sure everybody was okay, was my priority.”

There were no injuries reported as the plastic plant burned, as huge plumes of pitch black smoke poured into the air for hours.

Neighborhood adjacent to Poly-America fire in Grand Prairie (CBS 11).

“That’s dangerous. That’s a lot of chemicals in the air,” says Steven Crain, who lives nearby with his elderly parents. “Just think, if it had blew back this way? People have asthma. That’s dangerous.”

Others admitted to worry.

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“I was very concerned with it being that company,” says Helen Pennie, “didn’t want to inhale all of that, whatever it is.”

“Still would like to know if there were any health hazard materials that we should be concerned with,” adds her husband, Charlie Pennie. “The smoke was heavy; but, it seemed to be blowing off to the West.”

However, doctors are warning even those not in the direct path of the smoke to take precautions.

“There’s polyethylene and polyeurethane,” says Dr. Glenn Hardesty, an emergency room physician with Texas Health Resources.

He says since so little is known right now of what exactly was burning, Dr. Hardesty says anyone with respiratory issues in the area should stay indoors, as toxins can linger in the air, even after the smoke has cleared.

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” Coughing, wheezing, up to difficulty breathing,” says Dr. Hardesty. “Not knowing the exact nature of what’s in the air, it makes sense for the next one to two days to avoid being outdoors in those areas that were directly impacted.”