INVESTIGATING THE UNDERLYING MECHANISMS OF MICROCYSTIN PRODUCTION IN A TEMPERATE, MESO-EUTROPHIC LAKE

Harmful algal blooms (HABs), which can contain toxin-producing cyanobacteria, pose a threat to human and environmental health. Conditions that promote HAB formation are characterized reasonably well, but the mechanisms controlling when certain cyanotoxins are produced are poorly constrained. Microcystins, the most common class of cyanotoxin, have many associated human health risks including liver disease and cancer. These toxins are known to contaminate drinking water and impact recreational activities, therefore it is critical to identify drivers of HAB toxicity. Chautauqua Lake (CL) in western New York is heavily used for both recreational and drinking-water purposes, but suffers from seasonal HABs, particularly in the south basin. Here, ultra-high performance liquid chromatography coupled mass spectrometry (UHPLC-MS) is used to quantify microcystin concentration in CL water samples collected in 2022 and 2023. These results are correlated with cyanobacterial DNA, water chemistry, and weather data to analyze spatiotemporal trends in microcystin concentration compared to those environmental variables. In both years, there were higher concentrations of microcystins in CL’s south basin than in the north basin. There is statistically significant interannual variability in microcystin, total nitrogen and ammonia, fluorescent dissolved organic matter (fDOM), and chlorophyll-A concentrations. The findings in this study suggest that those variables could play an important role in microcystin regulation and synthesis in CL and similar meso-eutrophic lakes.

Presentation Preference: Oral

Primary Presenter: Abigail Ross, University of Colorado Boulder (abro8212@colorado.edu)

Authors:

Manuel Castro Berman, Rensselaer Polytechnic Institute  (castrm2@rpi.edu)

Vincent Moriarty, Rensselaer Polytechnic Institute  (moriav2@rpi.edu)

Allison Hrycik, Darrin Freshwater Institute  (hrycia@rpi.edu)

Kevin Rose, Rensselaer Polytechnic Institute  (rosek4@rpi.edu)

Jonathan Dordick, Rensselaer Polytechnic Institute  (dordick@rpi.edu)

Jacob Shelley, Rensselaer Polytechnic Institute  (shellj@rpi.edu)