Holy Toledo! This Nasty Lake Erie Algae Bloom is the Likely Source of the Toxin Causing Your Drinking Water Woes

By Tom Yulsman | August 3, 2014 7:16 pm

An algae bloom in the western part of Lake Erie just offshore of Toledo, Ohio is visible in this image captured today (Aug. 3) by NASA’s Terra satellite.

Do you see it? The green slime at the western end of Lake Erie in the satellite image above? That could be the source of the toxins  that have caused the city of Toledo, Ohio to impose a drinking water ban affecting 500,000 people.

The ban continued today, as further testing revealed evidence of the toxin microcystin in a drinking water plant.

Microcystin is produced by blooms of cyanobacteria, also known as blue-green algae. In the image from NASA’s Terra satellite above, a widespread bloom is evident; whether it contains the the cyanobacteria that produce microcystin I can’t say for sure. But I’d put money on it.

I didn’t want to say this in the headline, because I didn’t want to seem sensationalistic: Mycrocystin-LR, which is commonly produced by cyanobacteria blooms, is actually more toxic than sodium cyanide.  So no wonder Toledo imposed the drinking water ban!

According to an “urgent water notice” from the city:

Chemists testing water at Toledo’s Collins Park Water Treatment Plant had two sample readings for microcystin in excess of the recommended “DO NOT DRINK” 1 microgram per liter standard.  This notice applies to ALL customers of Toledo water.

What happens if you should drink the stuff?: 

Consuming water containing algal toxins may result in abnormal liver function, diarrhea, vomiting, nausea, numbness or dizziness.  Seek medical attention if you feel you have been exposed to algal toxins and are having adverse health effects.   Contact a veterinarian immediately if pets or livestock show signs of illness.

Folks in Toledo haven’t been the only people to be afflicted by a nasty algae bloom recently. It happened last week across the Atlantic in the Baltic Sea. I wrote about it here (and included some icky pictures). Since that bloom affected a sea, as far as I know it did not impact drinking water supplies. But it was widespread and washed ashore in Sweden.

Why do these things happen? As I wrote in my post about the Baltic bloom:

Although blooms can be a completely natural phenomenon, we humans have devised a special recipe that seems to cook up big batches of the stuff:

  • Start with runoff of fertilizer and animal waste from farms and pastures, along with effluent from towns, cities and industrial facilities. These ingredients provide many of the nutrients cyanobacteria thrive on.
  • Next, stir in some pesticides and other chemicals, which help deplete the natural grazing organisms that ordinarily would help control their growth.
  • Lastly, turn up the heat to a nice summer simmer, and…

Half a million people are left scrambling to find drinking water.

CATEGORIZED UNDER: Environment, select, Top Posts
  • brucegirl

    If this doesn’t tip the scales in favor of organic farming I don’t know what will…

    • aka darrell

      Right. You don’t know what will.

    • disqus_atlq8Zmtsd

      This is hardly a new phenomenon. The scales will tip to organic farming the second that organic farming can match the yields attained by using chemicals.

      Also have to point out that the nutrient component of fresh water eutrophication is a very real problem using organic methods as well. The source of contamination in an event could very easily be rain water runoff with high amounts of cow dung that had been used as fertilizer.

  • Buddy199

    What do they call it, The Mistake on the Lake?

    • RussK

      Actually Cleveland had that distinction after a river near there caught fire. Toledoan Ned Skelton actually was instrumental in the initial cleanup of Lake Erie but most everybody around the lake has dropped thier guard and let the algae get back to big numbers.

  • mary

    Thanks to the huge chemical companies and the irresponsible use of fertilizers and pesticides washing into our water ways we are stricken with non potable water. Wise up folks and boycott these huge chemical companies. They don’t give a care about you or your water.



ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

About Tom Yulsman

Tom Yulsman is Director of the Center for Environmental Journalism and a Professor of Journalism at the University of Colorado, Boulder. He also continues to work as a science and environmental journalist with more than 30 years of experience producing content for major publications. His work has appeared in the New York Times, Washington Post, Audubon, Climate Central, Columbia Journalism Review, Discover, Nieman Reports, and many other publications. He has held a variety of editorial positions over the years, including a stint as editor-in-chief of Earth magazine. Yulsman has written one book: Origins: the Quest for Our Cosmic Roots, published by the Institute of Physics in 2003.


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