Photo by Aerial Associates Photography, Inc. (Zachary Haslick) via NOAA cc 2.0

ANN ARBOR—Five years ago this week, more than 400,000 people in northwestern Ohio and southeastern Michigan were left without safe tap water for more than two days after cyanobacteria-produced toxins were detected in the city of Toledo’s drinking water supply.

University of Michigan scientists are involved in several cyanobacteria-related projects, some of which are a direct result of the August 2014 Toledo water crisis. Some of the studies focus on basic cyanobacteria biology, while others aim to protect public health. A few of the projects are summarized below.

New robotic labs to track toxicity of Lake Erie cyanobacteria bloom this summer

New robotic lake-bottom laboratories will keep a watchful eye on western Lake Erie’s cyanobacteria bloom this summer, and a mobile lab housed inside a cigar-shaped autonomous underwater glider will be tested there in mid-August.

In a direct response to the 2014 Toledo water crisis, a research team from U-M’s Cooperative Institute for Great Lakes Research and the National Oceanic and Atmospheric Administration field-tested an environmental sample processor, or ESP, in fall 2016 in western Lake Erie and deployed it for regular service in July 2017.

Cyanobacteria bloom biology: Nevertheless, they persisted

Cyanobacteria blooms in places like Lake Erie can persist for months, long after most of the available nutrients in the water have been depleted. How do these troublesome photosynthetic organisms, sometimes called blue-green algae, manage it?

In a study published online July 25 in the journal Molecular Ecology, U-M biologists and their colleagues report that different strains of the common cyanobacterium Microcystis aeruginosa appear to be adapted to different levels of the nutrient phosphorus in the water.

Searching for previously unknown toxins and potential medicines in Lake Erie cyanobacteria blooms

U-M researchers are collecting and analyzing samples from this summer’s Lake Erie cyanobacteria bloom to discover and characterize previously unknown toxins that may threaten human health, as well as compounds that could serve as sources of new medicines.

The project is led by U-M microbiologist and oceanographer Greg Dick and David Sherman, a professor of medicinal chemistry who studies natural chemical compounds made by microorganisms.

Cool, wet weather made for a challenging 2019 Lake Erie cyanobacteria bloom forecast

This summer’s cyanobacteria bloom in western Lake Erie is expected to be a large one, but determining just how big it is likely to get was challenging for forecasters, including U-M aquatic ecologist Don Scavia.

Scavia is a member of the federally funded research team that issues a Lake Erie cyanobacteria bloom forecast each year in early July. This year’s forecast calls for bloom that measures 7.5 on the severity index.

Flying slime may bring toxins with it

In 2018, U-M chemistry researchers Andrew Ault and Kerri Pratt showed that when waters that contain harmful algal blooms break against shorelines and piers, biological material from those algal blooms can go airborne.

Next, Ault turned his attention to whether toxins from those algal blooms could become airborne as well. The answer? Yes.

“We have collected samples from Mona Lake in western Michigan as well as some other lakes, and when we generate aerosols from that water in the lab, we do see toxins from the water go into the aerosol,” Ault said. “Now, we plan to study how far these toxins can transport inland from lakes—measuring it not just from collecting aerosols in the lab, but in the field.”