Even if you don't drink it, the water in the homes inundated by Hurricane Harvey flooding can be dangerous, Dr. Oz says.
There are fears of a looming health crisis due to toxic water flooding the streets of Houston.
Read: How You Can Help the Victims of Hurricane Harvey
That water flooding into homes isn't just rain; it's mixed with sewage and chemicals, bacteria and potentially disease.
Dr. Mehmet Oz of The Dr. Oz Show told Inside Edition the water could be incredibly dangerous.
"There is salmonella, there is E.coli, there is cholera, which is potentially in these waters," he told Inside Edition. "You also have dysentery because they are walking through dirty stuff."
There has been shocking video of many people treading through the filthy floodwater.
"Any open wound with stagnant water is the perfect recipe for infection,” he said. “A paper cut could give you a life-threatening infection if it is the wrong bacteria.”
Bacteria aren't the only danger in the water, as creatures like alligators could be lurking.
One woman shot video of a gator swimming around in her flooded backyard.
Another danger is fire ants. Whole colonies of the stinging insects have been seen floating around Houston.
Meanwhile, thousands of people continue to be rescued by air and by boat.
One teenager was up his neck in water and nearly drowned when he tried to retrieve a kayak. Rescuers threw him a rope and thankfully, he was pulled to safety.
Read: TV Reporter Helps Woman in Labor During Live Coverage of Hurricane Harvey
One mom frantically appealed for help on social media after she was separated from her baby.
Dajauh Henix posted: “Please keep a look out for my baby we were separated while evacuating. Pleaseeeee.”
A rescue worker saw the appeal and immediately posted a photo of the 8-month-old baby. Mom and baby have since been reunited.
Watch: Miracle Baby: Mother Gives Birth in Home During Hurricane Harvey
