Algal Toxin Variation in Lake Erie Fish Tissue

Lake Erie is an important economic and cultural resource, but it is threatened by recurring blooms of toxin-producing cyanobacteria. Microcystin, a potent liver toxin linked to human and animal illness and death, has been found in fish from Lake Erie, sometimes in excess of World Health Organization guidelines for safe consumption. Despite this, few studies have analyzed the variation of microcystin concentrations in fish within Lake Erie, and these past studies have derived conflicting results as to the risk posed to public health. This is likely because of the extremely variable nature of the algae blooms from year to year, and because of the different species on which each study focused.

To help address this gap in knowledge, in the summer of 2013 we gathered large samples of three of the most commonly harvested sportfish in Lake Erie: Walleye (n>35), Yellow Perch (n>20), and White Perch (n>50). By analyzing the toxin content of these fish, we are able to determine if fish size, species, location at harvest, and harvest time significantly affect the concentration of toxin in fish fillets, and whether any of the fish harvested during this time period exceed levels of microcystin established for safe consumption.