Scan Science and Technology
Contact Leading Edge Experts & Companies
Algaecides
The Experts below are selected from a list of 1065 Experts worldwide ranked by ideXlab platform
John H Rodgers – One of the best experts on this subject based on the ideXlab platform.
-
Laboratory-scale evaluation of algaecide effectiveness for control of microcystin-producing cyanobacteria from Lake Okeechobee, Florida (USA)
Ecotoxicology and environmental safety, 2020Co-Authors: Ciera Kinley-baird, Alyssa J Calomeni, John H Rodgers, David E. Berthold, Forrest W. Lefler, Maximiliano Barbosa, H. Dail LaughinghouseAbstract:Growth of microcystin-producing cyanobacteria in Lake Okeechobee (Florida, USA) and surrounding waters has resulted in adverse health impacts for humans and endangered species, as well as significant economic losses. As these issues worsen, there is growing pressure for efficacious solutions to rapidly mitigate harmful algal blooms (HABs) and protect critical freshwater resources. Applications of USEPA-registered Algaecides as management tactics meet many decision-making criteria often required by water resource managers (e.g., effective, scalable, selective), but have not yet been evaluated on a large scale within the Lake Okeechobee waterway. This study was conducted to bolster the peer-reviewed database for available management tactics against microcystin-producing cyanobacteria in waters of this region. Laboratory-scale experiments can be conducted first to minimize uncertainty at larger scales and improve confidence in decision-making. In this study, samples containing microcystin-producing cyanobacteria collected from Lake Okeechobee were exposed to several USEPA-registered Algaecides in laboratory toxicity experiments. Responses of target cyanobacteria were measured 3 days after treatment (DAT) in terms of cell density, chlorophyll-a concentrations, and phycocyanin concentrations. Based on responses of the cyanobacteria, minimum effective exposure concentrations were identified for each algaecide. Microcystin release (i.e. proportion of total microcystins in the aqueous phase) was measured and compared 1 DAT among effective exposures. Total microcystin concentrations were measured in effective treatments at 1, 4, and 9 DAT to discern potential for microcystin persistence following exposures to the effective formulations and exposure concentrations. Overall, several formulations including GreenClean Liquid® 5.0, GreenClean Liquid® 5.0 combined with Hydrothol® 191, and the copper-based Algaecides evaluated (Algimycin® PWF, Argos, Captain® XTR, Cutrine® Ultra, and SeClear®) achieved significant and similar effects on target cyanobacteria. The chelated copper-based formulations (Algimycin® PWF, Argos, Captain® XTR, and Cutrine® Ultra) resulted in relatively less microcystin release 1 DAT and lesser total microcystin concentrations 4 DAT. At 9 DAT, total microcystin concentrations were significantly lower than in untreated controls in all treatments evaluated. These results provide the necessary comparative performance data for preliminary decision-making and designing additional studies at larger scales. Importantly, the comparative toxicity data and approach provided in this study demonstrate the initial steps for development of site-specific management strategies for Lake Okeechobee and other areas impacted by harmful algal blooms with large spatial and temporal scales.
-
Microcystin-LR Degradation Following Copper-Based Algaecide Exposures
Water Air & Soil Pollution, 2018Co-Authors: Ciera M Kinley, Alyssa J Calomeni, Andrew D Mcqueen, Maas Hendrikse, Tyler D. Geer, Jenny Liang, Vanessa Friesen, Kyla J. Iwinski-wood, Monique C. Simair, John H RodgersAbstract:When copper-based Algaecides are used in aquatic systems to decrease cyanobacteria densities, endotoxin fate is a concern, due to the potential for human health and ecological risks. Pulse exposures of Algaecides can result in episodic low dissolved oxygen (DO) concentrations (
-
Characterization of Copper Algaecide (Copper Ethanolamine) Dissipation Rates Following Pulse Exposures
Water Air & Soil Pollution, 2017Co-Authors: Alyssa J Calomeni, Ciera M Kinley, Kyla J Iwinski, Andrew D Mcqueen, Maas Hendrikse, John H RodgersAbstract:Dissipation rates of copper following algaecide treatments resulting in pulse exposures can be accurately modeled if the component dissipation rates are known. Scaled experiments (in situ, laboratory and mesocosm) were used to parse and rank dominant processes from concurrent processes affecting copper fate in pulse exposures. Copper dissipation rates were measured cumulatively in situ and in mesocosms as well as individually in laboratory experiments. Predictions of the influence of individual dissipation rates on the cumulative dissipation rate were assessed mathematically. In situ aqueous copper dissipated rapidly following an algaecide treatment, with a measured half-life of 0.03 days. Based on laboratory experiments, the most rapid copper fate process was dilution with a half-life of 0.03 days, followed by sediment sorption with a half-life of approximately 3 days. Mesocosm experiments incorporating physical characteristics of the site (i.e., dilution, sediment, algae, and site water) resulted in similar copper dissipation rates (0.02 days) relative to the in situ copper dissipation rate. Prediction of the fate of copper from algaecide treatments requires incorporation of accurate estimates of dominant fate processes that can be determined physically and mathematically.
Alyssa J Calomeni – One of the best experts on this subject based on the ideXlab platform.
-
Laboratory-scale evaluation of algaecide effectiveness for control of microcystin-producing cyanobacteria from Lake Okeechobee, Florida (USA)
Ecotoxicology and environmental safety, 2020Co-Authors: Ciera Kinley-baird, Alyssa J Calomeni, John H Rodgers, David E. Berthold, Forrest W. Lefler, Maximiliano Barbosa, H. Dail LaughinghouseAbstract:Growth of microcystin-producing cyanobacteria in Lake Okeechobee (Florida, USA) and surrounding waters has resulted in adverse health impacts for humans and endangered species, as well as significant economic losses. As these issues worsen, there is growing pressure for efficacious solutions to rapidly mitigate harmful algal blooms (HABs) and protect critical freshwater resources. Applications of USEPA-registered Algaecides as management tactics meet many decision-making criteria often required by water resource managers (e.g., effective, scalable, selective), but have not yet been evaluated on a large scale within the Lake Okeechobee waterway. This study was conducted to bolster the peer-reviewed database for available management tactics against microcystin-producing cyanobacteria in waters of this region. Laboratory-scale experiments can be conducted first to minimize uncertainty at larger scales and improve confidence in decision-making. In this study, samples containing microcystin-producing cyanobacteria collected from Lake Okeechobee were exposed to several USEPA-registered Algaecides in laboratory toxicity experiments. Responses of target cyanobacteria were measured 3 days after treatment (DAT) in terms of cell density, chlorophyll-a concentrations, and phycocyanin concentrations. Based on responses of the cyanobacteria, minimum effective exposure concentrations were identified for each algaecide. Microcystin release (i.e. proportion of total microcystins in the aqueous phase) was measured and compared 1 DAT among effective exposures. Total microcystin concentrations were measured in effective treatments at 1, 4, and 9 DAT to discern potential for microcystin persistence following exposures to the effective formulations and exposure concentrations. Overall, several formulations including GreenClean Liquid® 5.0, GreenClean Liquid® 5.0 combined with Hydrothol® 191, and the copper-based Algaecides evaluated (Algimycin® PWF, Argos, Captain® XTR, Cutrine® Ultra, and SeClear®) achieved significant and similar effects on target cyanobacteria. The chelated copper-based formulations (Algimycin® PWF, Argos, Captain® XTR, and Cutrine® Ultra) resulted in relatively less microcystin release 1 DAT and lesser total microcystin concentrations 4 DAT. At 9 DAT, total microcystin concentrations were significantly lower than in untreated controls in all treatments evaluated. These results provide the necessary comparative performance data for preliminary decision-making and designing additional studies at larger scales. Importantly, the comparative toxicity data and approach provided in this study demonstrate the initial steps for development of site-specific management strategies for Lake Okeechobee and other areas impacted by harmful algal blooms with large spatial and temporal scales.
-
Microcystin-LR Degradation Following Copper-Based Algaecide Exposures
Water Air & Soil Pollution, 2018Co-Authors: Ciera M Kinley, Alyssa J Calomeni, Andrew D Mcqueen, Maas Hendrikse, Tyler D. Geer, Jenny Liang, Vanessa Friesen, Kyla J. Iwinski-wood, Monique C. Simair, John H RodgersAbstract:When copper-based Algaecides are used in aquatic systems to decrease cyanobacteria densities, endotoxin fate is a concern, due to the potential for human health and ecological risks. Pulse exposures of Algaecides can result in episodic low dissolved oxygen (DO) concentrations (
-
Characterization of Copper Algaecide (Copper Ethanolamine) Dissipation Rates Following Pulse Exposures
Water Air & Soil Pollution, 2017Co-Authors: Alyssa J Calomeni, Ciera M Kinley, Kyla J Iwinski, Andrew D Mcqueen, Maas Hendrikse, John H RodgersAbstract:Dissipation rates of copper following algaecide treatments resulting in pulse exposures can be accurately modeled if the component dissipation rates are known. Scaled experiments (in situ, laboratory and mesocosm) were used to parse and rank dominant processes from concurrent processes affecting copper fate in pulse exposures. Copper dissipation rates were measured cumulatively in situ and in mesocosms as well as individually in laboratory experiments. Predictions of the influence of individual dissipation rates on the cumulative dissipation rate were assessed mathematically. In situ aqueous copper dissipated rapidly following an algaecide treatment, with a measured half-life of 0.03 days. Based on laboratory experiments, the most rapid copper fate process was dilution with a half-life of 0.03 days, followed by sediment sorption with a half-life of approximately 3 days. Mesocosm experiments incorporating physical characteristics of the site (i.e., dilution, sediment, algae, and site water) resulted in similar copper dissipation rates (0.02 days) relative to the in situ copper dissipation rate. Prediction of the fate of copper from algaecide treatments requires incorporation of accurate estimates of dominant fate processes that can be determined physically and mathematically.
Kyla J Iwinski – One of the best experts on this subject based on the ideXlab platform.
-
Characterization of Copper Algaecide (Copper Ethanolamine) Dissipation Rates Following Pulse Exposures
Water Air & Soil Pollution, 2017Co-Authors: Alyssa J Calomeni, Ciera M Kinley, Kyla J Iwinski, Andrew D Mcqueen, Maas Hendrikse, John H RodgersAbstract:Dissipation rates of copper following algaecide treatments resulting in pulse exposures can be accurately modeled if the component dissipation rates are known. Scaled experiments (in situ, laboratory and mesocosm) were used to parse and rank dominant processes from concurrent processes affecting copper fate in pulse exposures. Copper dissipation rates were measured cumulatively in situ and in mesocosms as well as individually in laboratory experiments. Predictions of the influence of individual dissipation rates on the cumulative dissipation rate were assessed mathematically. In situ aqueous copper dissipated rapidly following an algaecide treatment, with a measured half-life of 0.03 days. Based on laboratory experiments, the most rapid copper fate process was dilution with a half-life of 0.03 days, followed by sediment sorption with a half-life of approximately 3 days. Mesocosm experiments incorporating physical characteristics of the site (i.e., dilution, sediment, algae, and site water) resulted in similar copper dissipation rates (0.02 days) relative to the in situ copper dissipation rate. Prediction of the fate of copper from algaecide treatments requires incorporation of accurate estimates of dominant fate processes that can be determined physically and mathematically.
-
Cell density dependence of Microcystis aeruginosa responses to copper algaecide concentrations: Implications for microcystin-LR release.
Ecotoxicology and environmental safety, 2017Co-Authors: Ciera M Kinley, Kyla J Iwinski, Maas Hendrikse, Tyler D. Geer, John H RodgersAbstract:Along with mechanistic models, predictions of exposure-response relationships for copper are often derived from laboratory toxicity experiments with standardized experimental exposures and conditions. For predictions of copper toxicity to algae, cell density is a critical factor often overlooked. For pulse exposures of copper-based Algaecides in aquatic systems, cell density can significantly influence copper sorbed by the algal population, and consequent responses. A cyanobacterium, Microcystis aeruginosa, was exposed to a copper-based algaecide over a range of cell densities to model the density-dependence of exposures, and effects on microcystin-LR (MC-LR) release. Copper exposure concentrations were arrayed to result in a gradient of MC-LR release, and masses of copper sorbed to algal populations were measured following exposures. While copper exposure concentrations eliciting comparable MC-LR release ranged an order of magnitude (24-h EC50s 0.03-0.3mg Cu/L) among cell densities of 106 through 107 cells/mL, copper doses (mg Cu/mg algae) were similar (24-h EC50s 0.005-0.006mg Cu/mg algae). Comparisons of MC-LR release as a function of copper exposure concentrations and doses provided a metric of the density dependence of algal responses in the context of copper-based algaecide applications. Combined with estimates of other site-specific factors (e.g. water characteristics) and fate processes (e.g. dilution and dispersion, sorption to organic matter and sediments), measuring exposure-response relationships for specific cell densities can refine predictions for in situ exposures and algal responses. These measurements can in turn decrease the likelihood of amending unnecessary copper concentrations to aquatic systems, and minimize risks for non-target aquatic organisms.
-
Influence of CuSO4 and chelated copper algaecide exposures on biodegradation of microcystin-LR.
Chemosphere, 2017Co-Authors: Kyla J Iwinski, Ciera M Kinley, Alyssa J Calomeni, John H Rodgers, Andrew D Mcqueen, Maas Hendrikse, Tyler D. Geer, Jenny Liang, Vanessa Friesen, Monique HaakensenAbstract:Abstract Copper exposures from algaecide applications in aquatic systems are hypothesized to impede bacterial degradation of microcystin (MC), a cyanobacterial produced hepatotoxin. Despite regulatory implications of this hypothesis, limited data exist on influences of copper-exposures on MC-degrading bacteria and consequent MC-degradation. In this study, influences of copper-algaecide concentrations and formulations on bacterial composition and microcystin-LR (MCLR) degradation were investigated. Microcystis aeruginosa was exposed to four concentrations (0–5.0 mg Cu L−1) of three copper-algaecide formulations, and rates and extents of MCLR degradation were measured. In untreated controls and following exposures of 0.1, 0.5, and 1.0 mg Cu L−1, MCLR concentrations decreased at a rate of ∼41–53 μg MCLR/L d−1. Following exposure to 5.0 mg Cu L−1 MCLR degradation rates decreased an order of magnitude to ∼3–7 μg MCLR/L d−1. Bacterial diversity decreased following copper-exposures greater than 0.1 mg Cu L−1 for all formulations. Relative abundance of certain groups of MC-degrading bacteria identified in treatments increased with increasing copper concentration, suggesting they may be less sensitive to copper exposures than other, MCLR and non MC-degrading heterotrophic bacteria present in the assemblage. Results from this study revealed that copper concentration can influence degradation rates of MCLR, however this influence was not significant within copper concentrations currently registered for use (≤1.0 mg Cu L−1) of the tested Algaecides. Copper formulation did not significantly alter degradation rates or bacterial composition. These data augment our understanding of the influences of copper algaecide-exposures on MCLR degradation, and can be used to inform more accurate risk evaluations and use of copper-Algaecides for management of MCLR-producing cyanobacteria.
Ciera M Kinley – One of the best experts on this subject based on the ideXlab platform.
-
Microcystin-LR Degradation Following Copper-Based Algaecide Exposures
Water Air & Soil Pollution, 2018Co-Authors: Ciera M Kinley, Alyssa J Calomeni, Andrew D Mcqueen, Maas Hendrikse, Tyler D. Geer, Jenny Liang, Vanessa Friesen, Kyla J. Iwinski-wood, Monique C. Simair, John H RodgersAbstract:When copper-based Algaecides are used in aquatic systems to decrease cyanobacteria densities, endotoxin fate is a concern, due to the potential for human health and ecological risks. Pulse exposures of Algaecides can result in episodic low dissolved oxygen (DO) concentrations (
-
Characterization of Copper Algaecide (Copper Ethanolamine) Dissipation Rates Following Pulse Exposures
Water Air & Soil Pollution, 2017Co-Authors: Alyssa J Calomeni, Ciera M Kinley, Kyla J Iwinski, Andrew D Mcqueen, Maas Hendrikse, John H RodgersAbstract:Dissipation rates of copper following algaecide treatments resulting in pulse exposures can be accurately modeled if the component dissipation rates are known. Scaled experiments (in situ, laboratory and mesocosm) were used to parse and rank dominant processes from concurrent processes affecting copper fate in pulse exposures. Copper dissipation rates were measured cumulatively in situ and in mesocosms as well as individually in laboratory experiments. Predictions of the influence of individual dissipation rates on the cumulative dissipation rate were assessed mathematically. In situ aqueous copper dissipated rapidly following an algaecide treatment, with a measured half-life of 0.03 days. Based on laboratory experiments, the most rapid copper fate process was dilution with a half-life of 0.03 days, followed by sediment sorption with a half-life of approximately 3 days. Mesocosm experiments incorporating physical characteristics of the site (i.e., dilution, sediment, algae, and site water) resulted in similar copper dissipation rates (0.02 days) relative to the in situ copper dissipation rate. Prediction of the fate of copper from algaecide treatments requires incorporation of accurate estimates of dominant fate processes that can be determined physically and mathematically.
-
Cell density dependence of Microcystis aeruginosa responses to copper algaecide concentrations: Implications for microcystin-LR release.
Ecotoxicology and environmental safety, 2017Co-Authors: Ciera M Kinley, Kyla J Iwinski, Maas Hendrikse, Tyler D. Geer, John H RodgersAbstract:Along with mechanistic models, predictions of exposure-response relationships for copper are often derived from laboratory toxicity experiments with standardized experimental exposures and conditions. For predictions of copper toxicity to algae, cell density is a critical factor often overlooked. For pulse exposures of copper-based Algaecides in aquatic systems, cell density can significantly influence copper sorbed by the algal population, and consequent responses. A cyanobacterium, Microcystis aeruginosa, was exposed to a copper-based algaecide over a range of cell densities to model the density-dependence of exposures, and effects on microcystin-LR (MC-LR) release. Copper exposure concentrations were arrayed to result in a gradient of MC-LR release, and masses of copper sorbed to algal populations were measured following exposures. While copper exposure concentrations eliciting comparable MC-LR release ranged an order of magnitude (24-h EC50s 0.03-0.3mg Cu/L) among cell densities of 106 through 107 cells/mL, copper doses (mg Cu/mg algae) were similar (24-h EC50s 0.005-0.006mg Cu/mg algae). Comparisons of MC-LR release as a function of copper exposure concentrations and doses provided a metric of the density dependence of algal responses in the context of copper-based algaecide applications. Combined with estimates of other site-specific factors (e.g. water characteristics) and fate processes (e.g. dilution and dispersion, sorption to organic matter and sediments), measuring exposure-response relationships for specific cell densities can refine predictions for in situ exposures and algal responses. These measurements can in turn decrease the likelihood of amending unnecessary copper concentrations to aquatic systems, and minimize risks for non-target aquatic organisms.
West M Bishop – One of the best experts on this subject based on the ideXlab platform.
-
biomass of the cyanobacterium lyngbya wollei alters copper algaecide exposure and risks to a non target organism
Bulletin of Environmental Contamination and Toxicology, 2020Co-Authors: West M Bishop, Ben E Willis, Gregory W Cope, Robert J RichardsonAbstract:Nuisance algal infestations are increasing globally in distribution and frequency. Copper-based Algaecides are routinely applied to control these infestations, though there is an ever-present concern of risks to non-target species. This research evaluated risks associated with a commonly applied chelated copper algaecide (Captain® XTR; SePRO Corporation) to a sentinel non-target species (Daphnia magna) and further assessed alteration of the exposure and toxicity when a nuisance mat-forming cyanobacterium, Lyngbya wollei, was present in exposures. Aqueous copper concentrations in treatments with algae significantly decreased within 1 h after treatment and averaged 57.5% of nominal amended Cu through the experiment duration. The 48 h LC50 values were 371 µg Cu/L with no algae present in exposures and increased significantly to 531 µg Cu/L when L. wollei was simultaneously exposed. This research provides information on the short-term fate of copper and hazard assessment by incorporating targeted binding ligands, as present in operational treatments.
-
Controlling Lyngbya wollei in three Alabama, USA reservoirs: summary of a long-term management program
Applied Water Science, 2019Co-Authors: Wesley T. Anderson, West M Bishop, Ben E Willis, Josh N. Yerby, Jason Carlee, C. Todd HortonAbstract:Large-scale Lyngbya wollei (Cyanobacteria, Oscillatoriales) infestations are increasing throughout the USA and globally and causing significant obstruction of water resource uses. Decision makers and stakeholders encountering this nuisance organism often seek management options. Many approaches to L. wollei management may be ineffective or not applicable to specific field sites. Chemical control with United States Environmental Protection Agency registered Algaecides has shown to be effective, although the specific formulation, concentration, and application frequency can all govern efficacy. This study summarizes results from a long-term and adaptive management program on extensive L. wollei infestations in three central Alabama, USA reservoirs (Lay Lake, Jordan Lake and Lake Mitchell) managed by Alabama Power Company. Multiple treatment strategies including numerous Algaecides, combinations and addition of surfactants were used in attempts to control the nuisance cyanobacterium and preserve multiple beneficial functions of the resource. Ultimately, operational shift toward one technology, a double-chelated copper algaecide with surfactants and emulsifiers (Captain^® XTR) resulted in more efficient and economical control. There were significant ( P
-
Modulating the Effect of Iron and Total Organic Carbon on the Efficiency of a Hydrogen Peroxide-Based Algaecide for Suppressing Cyanobacteria
Water Air & Soil Pollution, 2019Co-Authors: Elizabeth A. Crafton, West M Bishop, Teresa J. Cutright, Donald W. OttAbstract:The intensity and frequency of cyanobacteria-dominated harmful algal blooms (cHABs) has been increasing. A key issue associated with cHABs is the potential to release cyanotoxins, such as microcystin. One of the primary methods for addressing cHABs in a reservoir is the application of Algaecides. This research evaluated the impact of common environmental factors (i.e., Fe, total organic carbon) on the efficacy of a hydrogen peroxide-based algaecide to attain control of a targeted cyanobacterial population. The results found that sodium carbonate peroxydrate (SCP, trade name PAK®27) at half the manufacturer’s suggested application was effective at suppressing cyanobacteria for 2 weeks. For example, reactors that contained a full level of TOC and 1 mg/L Fe significantly decreased by 89% from 21,899 to 2437 ± 987 cells/mL ( p