In situ H2O2 treatment of blue-green algae contaminated reservoirs causes significant improvement in drinking water treatability.

Melo Rocha, Maria Aparecida; Clemente, Allan; Amorim Santos, Allan; da Silva Melo, Jessica; Pestana, Carlos J.; Lawton, Linda A.; Capelo-Neto, José

Abstract

The evaluation of water quality improvement brought about by in situ treatment of eutrophic water bodies, especially those used for human supply, is a challenging task since each water system responds differently. To overcome this challenge, we applied exploratory factor analysis (EFA) to understand the effects of using hydrogen peroxide (H2O2) on eutrophic water used as a drinking water supply. This analysis was used to identify the main factors that described the water treatability after exposing blue-green algae (cyanobacteria) contaminated raw water to H2O2 at both 5 and 10 mg L-1. Cyanobacterial chlorophyll-a was undetectable following the application of both concentrations of H2O2 after four days, while not causing relevant changes to green algae and diatoms chlorophyll-a concentrations. EFA demonstrated that the main factors affected by both H2O2 concentrations were turbidity, pH and cyanobacterial chlorophyll-a concentration, which are important variables for a drinking water treatment plant. The H2O2 caused significant improvement in water treatability by decreasing those three variables. Finally, the use of EFA was demonstrated to be a promising tool in identifying which limnological variables are most relevant concerning the efficacy of water treatment, which in turn can make water quality monitoring more efficient and less costly.

Citation

MELO ROCHA, M.A., CLEMENTE, A., AMORIM SANTOS, A., DA SILVA MELO, J., PESTANA, C.J., LAWTON, L.A. and CAPELO-NETO, J. 2023. In situ H2O2 treatment of blue-green algae contaminated reservoirs causes significant improvement in drinking water treatability. Chemosphere [online], 333, article 138895. Available from: https://doi.org/10.1016/j.chemosphere.2023.138895

• Journal Article Type: Article
• Acceptance Date: May 7, 2023
• Online Publication Date: May 13, 2023
• Publication Date: Aug 31, 2023
• Deposit Date: May 16, 2023
• Publicly Available Date: May 16, 2023
• Journal: Chemosphere
• Print ISSN: 0045-6535
• Electronic ISSN: 1879-1298
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 333
• Article Number: 138895
• DOI: https://doi.org/10.1016/j.chemosphere.2023.138895
• Keywords: Cyanobacteria; Water treatment; In-reservoir treatment; Exploratory factor analysis
• Public URL: https://rgu-repository.worktribe.com/output/1965829
• Additional Information: This article has been published with separate supporting information. This supporting information has been incorporated into a single file on this repository and can be found at the end of the file associated with this output.