Toxic Algal Bloom Found on Illinois River Near Starved Rock State Park

Algal toxins can cause sickness or other adverse health effects in people and pets

starved rock state park
Starved Rock State Park

A toxic algal bloom has been discovered on the Illinois River near Starved Rock State Park in LaSalle County, according to the Illinois Environmental Protection Agency.

Algal toxins sometimes produced by blue-green algae can cause sickness or other adverse health effects in people and pets, depending on the amount and type of exposure, according to a news release issued by IEPA.

The agency collected samples late last week along the northern bank of the Illinois River at the Starved Rock Lock and Dam. On Thursday, the state laboratory confirmed the microcystin level in the sample at 138 ppb, well above the health advisory limit. 

The very young, elderly, and people with compromised immune systems are most at risk if exposed to algal toxins. Symptoms of exposure include rashes, hives, diarrhea, vomiting, coughing or wheezing, the news release stated.

Residents who plan to recreate in, on, or near Illinois rivers, lakes or streams are advised to avoid contact with water that:

  • looks like spilled, green or blue-green paint
  • has surface scums, mats or films
  • is discolored or has green-colored streaks
  • has greenish globs suspended in the water below the surface

Residents are advised to not let pets drink from water with any of the above characteristics. If you or your pet come into contact with water you suspect may have a bloom of blue-green algae, rinse off with clean, fresh water as soon as possible.

If you are concerned you're experiencing symptoms that are a result of exposure to algal toxins, contact your health care provider or call the Illinois Poison Center at 1-800-222-1222.

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