A Utah woman is reportedly in extremely critical condition after a highly toxic chemical mixed with her iced tea at a BBQ restaurant. It happened when the 67-year-old woman filled up a cup of sweet tea at the self-serve beverage station at Dickey’s Barbecue Pit on Sunday, according to police in South Jordan.

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When she took a sip, she felt an instant burning in her mouth, police said.

Here's more from The Salt Lake Tribune:

She tried to spit out the tea, but her mouth and throat suffered severe burns, Winkler said. Her husband took her to a nearby hospital, and she was flown to University Hospital’s burn unit, where she remained in "extremely critical condition" on Wednesday night, Winkler said.

"We’re not sure how, but a highly toxic industrial cleaning chemical somehow made its way into the tea," Winkler said.

The chemical is 67 percent sodium hydroxide, commonly known as lye, Winkler said. It is used to clean grease off the restaurants fryers and appears to have been mixed with the tea accidentally.

The restaurant was cooperating with the investigation, Winkler said.

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