CHICAGO (CBS) — Dangerous blooms of algae are being found in Illinois waters, and the Illinois Environmental Protection Agency and Department of Public Health are warning of risks to humans and pets.

The algae, which is blue-green with an almost paint-like sheen, is linked to the recent deaths of dogs.

Dogs that swim in it can show symptoms of distress and nausea in less than 30 minutes.

A North Carolina couple lost their three dogs to algae poisoning at a lake last Friday.

“People need to know about this,” said Melissa Martin. “I mean, like I said, if we had any clue that this was a thing, they would’ve never come. I had no idea.”

Look out for water that looks like blue-green paint and appears to have clumps of algae right under the surface.

Anyone who spots it should notify the Illinois EPA.