Have you seen the videos of people throwing boiling water into the air to watch it freeze instantly? It's the latest viral challenge, and it's sending people to the hospital.
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Within the last few weeks, parts of the United States have been affected by the polar vortex, which occurs when circulating winds from the north pole travel southward and cause below freezing temperatures.
To test just how cold the weather has been, folks have been tossing boiling water into the sky to watch it turn into tiny ice crystals.
Eight people who took part in the challenge have been treated at the burn center at Chicago's Loyola University Medical Center, according to the Chicago Sun-Times.
The patients treated range in age from three to 53, and have suffered injuries to their feet, arms, hands and face with varying degrees of burns.
A burn can penetrate all layers of the skin, according to the Centers for Disease Control and Prevention. It can leave it charred with white, black or brown patches. Symptoms of severe cases can include persistent pain and redness, swelling, fever, blisters that are larger than two inches or that ooze. Doctors may treat burns with bandages, antibiotics or even tetanus shots.
The stunt hasn’t only affected those throwing the water. Witnesses have been affected, too. The water can blow back and burn those watching, if a gust of wind suddenly arises.
"We strongly warn people to not perform the boiling water challenge," Loyola burn surgeon Arthur Sanford told the Chicago Sun-Times. "There is no safe way to do it."