LC/MS/MS Analysis of Benthic Cyanobacterial Blooms in Stormwater and Retention Ponds

Drinking Water
Oral Presentation

Prepared by S. Oehrle1, W. Strangman2, A. Tatters3
1 - Waters Lab at Northern Kentucky University, Chemistry Department, 100 Nunn Drive, Highland Heights, KY, 41099, United States
2 - University of North Carolina-Wilmington, Chemistry Department, Wilmington, NC, United States
3 - U.S. Environmental Protection Agency, Office of Research and Development, , , United States

Contact Information: [email protected]; 859-572-5409


Extensive cyanobacteria-dominated mats were observed during late summer of 2021 within a stormwater retention pond network in northwest Florida. Common in residential communities across the region, such ponds may be routinely visited by humans, domestic and wild animals, and often contain a variety of aquatic life. Accordingly, we investigated the temporal heterogeneity of potentially toxic cyanobacteria, associated toxins, and ‘under the radar’ bioactive peptides throughout the fall at several sites within the network. Multiple toxin classes were detected in whole water samples using targeted LC/MS/MS analysis including levels that far exceeded national recreational guidelines. Non-targeted analysis also revealed a collection of potentially unknown cyanobacteria-associated compounds that, along with known toxins, oscillated with periods of heavy rainfall and temperature variation. Furthermore, these retention ponds may serve as a consistent source for cyanobacteria biomass accumulation that is transported downstream in the form of cells for colonization and cyanotoxins to estuarine waters. Data from these and other ponds within the US will be discussed showing the wide variety of toxins that can be present in freshwater systems.