Removal and degradation of microcystins from drinking water using biofilters


Project ID:  D2018-52



Harmful algal blooms (HABs) release microcystin (MC) toxins that can end up in drinking water, causing a range of illnesses, including liver cancer. Currently, water treatment facilities remove or degrade MC using chlorination, ozonation, activated carbon adsorption, and/or floculation. However, those techniques are not ideal because of high costs, limited removal efficiencies, and they lead to the production of harmful byproducts or hazardous waste.


Invention Description

Researchers have identified bacterial isolates that are able to degrade MC toxins at a daily rate of 2 to 19 parts per billion. Based on recorded MC toxin levels in Lake Erie in recent years, these degradation rates would be able to effectively remove MC from drinking water supplies. The bacterial isolates also have been shown to form robust biofilms on filtering substrates, such as sand, indicating that they could be used in biologically-active filters - biofilters. Biofilters are a cost-effective and safe alternative to the use of chemicals and other conventional water treatment practices.



-       Filtration and degradation of MCs for aqueous solutions, such as drinking water



-       Reduce or eliminate use of harmful chemicals

-       Bacterial isolates are inexpensive and easily grown

-       Uses natural bacteria that are not known to cause human disease

-       Standard water treatment facilities chlorinate water after filtration, eliminating the potential risk of adding bacteria to a water treatment facility

-       No need to treat for toxic byproducts


IP Status:       Patent Pending


Publication:        A Thees, E Atari, J Birbeck, J Westrick, J Huntley. Isolation and characterization of Lake Erie bacteria that degrade the cyanobacterial microcystin toxin MC-LR. J. Great Lakes Res. 16 Nov. 2018.


Patent Information:
For Information, Contact:
Katherine Pollard
Licensing Associate
The University of Toledo
Jason Huntley
Alison Thees
Harmful algal bloom