Effectiveness of ozone nanobubble treatments on high biomass cyanobacterial blooms: A mesocosm experiment and field trial

Justin D Chaffin; David E Berthold; Eugene C Braig; Josh D Fuchs; Rachel S Gabor; Stephen J Jacquemin; Haley E Kuhn; Lillian D Labus; H Dail Laughinghouse; Forrest W Lefler; Heath E Mash; Heather A Raymond; Holly Stanley; Autumn T Taylor; Linda K Weavers; Skye Wendel

doi:10.1016/j.jenvman.2024.123406

Effectiveness of ozone nanobubble treatments on high biomass cyanobacterial blooms: A mesocosm experiment and field trial

J Environ Manage. 2024 Nov 21:372:123406. doi: 10.1016/j.jenvman.2024.123406. Online ahead of print.

Authors

Justin D Chaffin¹, David E Berthold², Eugene C Braig³, Josh D Fuchs⁴, Rachel S Gabor⁵, Stephen J Jacquemin⁶, Haley E Kuhn⁴, Lillian D Labus⁵, H Dail Laughinghouse², Forrest W Lefler², Heath E Mash⁷, Heather A Raymond⁸, Holly Stanley⁵, Autumn T Taylor⁹, Linda K Weavers⁴, Skye Wendel⁶

Affiliations

¹ F.T. Stone Laboratory and Ohio Sea Grant, The Ohio State University, 878 Bayview Ave. P.O. Box 119, Put-In-Bay, OH 43456, USA. Electronic address: chaffin.46@osu.edu.
² Agronomy Department, Fort Lauderdale Research and Education Center, University of Florida-IFAS, 3205 College Avenue, Davie, FL 33314, USA.
³ Ohio State University Extension, School of Environment and Natural Resources, 2021 Coffey Rd., Columbus, OH 43210, USA.
⁴ Civil, Environmental and Geodetic Engineering and Ohio Water Resources Center, The Ohio State University, 2070 Neil Ave., Columbus, OH 43210, USA.
⁵ School of Environment and Natural Resources, The Ohio State University, 2021 Coffey Rd, Columbus, OH 43210, USA.
⁶ Agriculture and Water Quality Education Center, Wright State University - Lake Campus, Celina, OH 45822, USA.
⁷ Center for Environmental Solutions and Emergency Response, Office of Research and Development, United States Environmental Protection Agency, 26 W. Martin Luther King Dr., Cincinnati, OH 45268, USA.
⁸ Office of Research and Graduate Education, College of Food, Agricultural, and Environmental Sciences, The Ohio State University, 2120 Fyffe Rd, Columbus, OH 43210, USA.
⁹ F.T. Stone Laboratory and Ohio Sea Grant, The Ohio State University, 878 Bayview Ave. P.O. Box 119, Put-In-Bay, OH 43456, USA; Agronomy Department, Fort Lauderdale Research and Education Center, University of Florida-IFAS, 3205 College Avenue, Davie, FL 33314, USA.

PMID: 39577190
DOI: 10.1016/j.jenvman.2024.123406

Abstract

Cyanobacterial harmful algae blooms (cyanoHABs) are a global threat to water resources, and lake managers need effective strategies to suppress or control them. Algaecides may have negative environmental impacts, and their use is becoming restricted. Nanobubble ozone technology (NBOT) is an emerging water treatment option with potentially fewer negative impacts. We assessed the effectiveness of NBOT in treating Planktothrix cyanoHAB from Grand Lake St Marys (GLSM, Ohio USA) in a mesocosm (2,000L) experiment and two 4-week trials in a GLSM embayment (Sunset Beach, SBE; ∼4.7∗10⁷ L). In mesocosms, the medium (1.21 ± 0.08 ozone to dissolved organic carbon ratio, O₃:DOC) and high (2.04 ± 0.07 O₃:DOC) doses decreased both chlorophyll a (chl-a) and phycocyanin by 98-99% and microcystins by 62% and 92%, respectively. The low dose (0.68 ± 0.05 O₃:DOC) decreased chl-a and phycocyanin by over 70%. No effect was observed for chl-a nor microcystins in both oxygen-only nanobubble mesocosm treatments and the SBE NBOT trial. The average O₃:DOC at SBE was less than the low NBOT mesocosm experiment dose, and the percentage of water treated was lower. DOC chemistry, as indicated by SUVA_254, was more oxidized at the NBOT outlet than the inlet in the SBE trial, suggesting interaction with ozone. However, no differences were observed 3m from the outlet, indicating minimal treatment reach. The mesocosm experiment highlighted NBOT's ability to control cyanoHABs, but the limited effectiveness of NBOT at SBE was likely due to high cyanobacteria biomass and DOC at the onset of treatment, low O₃:DOC, and low percentage of lake water instantaneously treated.

Keywords: Control strategies; CyanoHABs; Eutrophication; Grand lake St Marys; Microcystin; Nanobubble ozone treatment; Planktothrix.