The Influence of Algal Toxins and Taste-and-Odor Compounds on Water Usage in the Western Basin of Lake Erie

Abstract

The main purpose of this project was to determine if Microcystis aeruginosa, a toxic cyanobacteria species, was also a producer of taste-and-odor compounds. This was done using gene sequencing. The secondary purpose was to determine biotic and abiotic factors that contribute to taste-and-odor events during algal blooms. Understanding the factors influencing taste-and-odor production is important because it can have a tremendous effect on how people will continue to use water from Lake Erie. Sampling took place at nine open water areas in the western Lake Erie basin and near the water intake sites of two island communities. High geosmin levels (>> 0.004 ppb detectable limit) were detected at multiple sites but genetic confirmation could not be obtained. Statistical analyses showed a correlation between geosmin, chlorophyll a, and total phosphorus and that these factors may also be a cause for geosmin production. Phytoplankton counts also showed that Anabaena flos-aquae and Planktothrix sp. were present. These are not only known toxin-producers but also producers of taste-andcompounds. This study could not confirm or deny if Microcystis is a producer of these compounds as well as algal toxins. However, this phenomenon is occurring throughout the basin at locations where people use water recreationally and for consumption. If western Lake Erie is going to be removed from the Areas of Concern list then this situation must be better understood and this includes further study of whether or not Microcystis is a producer of these compounds as well as identifying the contributions made by these known taste-and-odor producers.