Grantee Research Project Results
Final Report: Monitoring, Photochemical Fate, and Oxidative Degradation by UV and Solar-based Catalytic Technologies of Cyanotoxins in Freshwater Estuaries
EPA Grant Number: R833223Title: Monitoring, Photochemical Fate, and Oxidative Degradation by UV and Solar-based Catalytic Technologies of Cyanotoxins in Freshwater Estuaries
Investigators: Dionysiou, Dionysios D. , Miller, Cheryl L. , Deis, Donald R. , Westrick, Judy , O'Shea, Kevin
Institution: University of Cincinnati , Lake Superior State University , Green Water Laboratories/CyanoLab , PBS&J , Florida International University
Current Institution: University of Cincinnati , Florida International University , Green Water Laboratories/CyanoLab , Lake Superior State University , PBS&J
EPA Project Officer: Aja, Hayley
Project Period: April 1, 2007 through March 31, 2010
Project Amount: $679,589
RFA: Development and Evaluation of Innovative Approaches for the Quantitative Assessment of Pathogens in Drinking Water (2005) RFA Text | Recipients Lists
Research Category: Drinking Water , Water
Objective:
The main objective is to develop an active collaboration to monitor, determine the photochemical fate and evaluate potential photochemical (UV and solar-based) treatment technologies for cyanotoxins. To accomplish this, we will: (1) evaluate the photolytic degradation of microcystins and identify the fate and partitioning of microcystins in the estuarine portion of the lower St. Johns River in Florida and several locations in the Great Lakes; (2) investigate the mechanisms of the photochemical and photocatalytic transformations of cyanotoxins present in synthetic solutions and real samples from the Great Lakes and Florida by visible and solar irradiation; (3) explore solar-driven catalytic systems for the destruction of cyanotoxins in water; and (4) investigate the fate of cyanotoxins under UV (254 nm) or broader spectrum at various levels of UV fluence to simulate UV disinfection systems in several drinking water treatment plants.
Summary/Accomplishments (Outputs/Outcomes):
Over the entire period of funding, we conducted several research activities. We have performed:
- Monitoring and identification of several Great Lake Utilities, one Lake St. Clair Utility and St. John’s River with sampling, water quality analysis and quantification of microcystins and other cyanobacteria.
- isolation and purification of a commonly found microcystin, microcystin-LR (MC-LR), from large bloom of blue green algae (BGA) at a South Florida site. Detailed kinetic and product studies on the reactions of hydroxyl radicals with MC-LR were conducted. Radiolysis studies were used to determine the primary reaction pathways and kinetic parameters for the reactions of hydroxyl radical with MC-LR. Our results include representative rate constants and partition of hydroxyl radical reactions based on the reactivities of surrogate substrates and individual amino acids.
- Development of highly efficient nitrogen doped TiO2 photocatalysts and, for the first time, their environmental application in destroying a commonly found cyanobacterial toxin, MC-LR. The synthesized nanoparticles exhibited enhanced structrutal properties and functionalities such as mesoporous structure and narrowed band gap energy for visible light sensitization. MC-LR was effectively degraded using these nanoparticles under visible light irradiation. The effects of initial pH, toxin adsorption and initial toxin concentration on the degradation efficiency of the TiO2 catalyst were studied and showed that acidic conditions are preferable for the degradation.
- Identification of 11new reaction intermediates of MC-LR with TiO2 photocatalysis to establish degradation pathways and mechanisms by hydroxyl radical attack.
- Development of highly efficient visible light-activated nitrogen and fluorine co-doped TiO2 nanoparticles and films for the destruction of MC-LR.
- Analysis of the operational parameters and elucidation of MC-LR intermediates with TiO2 films under UV light.
- Synthesis of sulfur-doped TiO2 films with visible light activity towards the degradation of MC-LR.
- Degradation experiments of MC-LR with germicidal UV/H2O2 under synthetic and natural waters.
Conclusions:
The scientific information and data generated through this project:
- provided a better understanding on the occurrence of cyanotoxins in specific freshwater estuaries and interactions of selected cyanotoxins with light and their photochemical fate in freshwater estuaries,
- evaluated the role of novel TiO2-based catalytic materials to destroy cyanotoxins in water as an approach to develop engineering technologies utilizing solar radiation as a renewable source of light,
- investigated the mechanisms of transformation and reaction pathways of selected cyanotoxins with radicals species formed through TiO2 photocatalysis, and (iv) investigated the magnitude of photochemical transformation of cyanotoxins under specific range of UV radiation fluence in consideration with the UV fluence applied in typical UV disinfection treatment units or required to inactivate specific pathogenic microorganisms.
Journal Articles on this Report : 16 Displayed | Download in RIS Format
Other project views: | All 54 publications | 17 publications in selected types | All 16 journal articles |
---|
Type | Citation | ||
---|---|---|---|
|
Antoniou MG, Shoemaker JA, de la Cruz AA, Dionysiou DD. Unveiling new degradation intermediates/pathways from the photocatalytic degradation of microcystin-LR. Environmental Science & Technology 2008;42(23):8877-8883. |
R833223 (2008) R833223 (Final) |
Exit |
|
Antoniou MG, Shoemaker JA, de la Cruz AA, Dionysiou DD. LC/MS/MS structure elucidation of reaction intermediates formed during the TiO2 photocatalysis of microcystin-LR. Toxicon 2008;51(6):1103-1118. |
R833223 (2008) R833223 (Final) |
Exit Exit Exit |
|
Antoniou MG, Nicolaou PA, Shoemaker JA, de la Cruz AA, Dionysiou DD. Impact of the morphological properties of thin TiO2 photocatalytic films on the detoxification of water contaminated with the cyanotoxin, microcystin-LR. Applied Catalysis B: Environmental 2009;91(1-2):165-173. |
R833223 (Final) |
Exit |
|
Antoniou MG, de la Cruz AA, Dionysiou DD. Degradation of microcystin-LR using sulfate radicals generated through photolysis, thermolysis, and e− transfer mechanisms. Applied Catalysis B: Environmental 2010;96(3-4):290-298. |
R833223 (Final) |
Exit Exit |
|
Antoniou MG, de la Cruz AA, Dionysiou DD. Intermediates and reaction pathways from the degradation of microcystin-LR with sulfate radicals. Environmental Science & Technology 2010;44(19):7238-7244. |
R833223 (Final) |
Exit |
|
Chen L, Dionysiou DD, O’Shea K. Complexation of microcystins and nodularin by cyclodextrins in aqueous solution, a potential removal strategy. Environmental Science & Technology 2011;45(6):2293-2300. |
R833223 (Final) |
Exit |
|
Choi H, Antoniou MG, Pelaez M, de la Cruz AA, Shoemaker JA, Dionysiou DD. Mesoporous nitrogen-doped TiO2 for the photocatalytic destruction of the cyanobacterial toxin microcystin-LR under visible light irradiation. Environmental Science & Technology 2007;41(21):7530-7535. |
R833223 (Final) |
Exit |
|
de la Cruz AA, Antoniou MG, Hiskia A, Pelaez M, Song W, O'Shea KE, He X, Dionysiou DD. Can we effectively degrade microcystins? -- Implications on human health. Anti-Cancer Agents in Medicinal Chemistry 2011;11(1):19-37. |
R833223 (Final) |
Exit |
|
Han C, Pelaez M, Likodimos V, Kontos AG, Falaras P, O'Shea K, Dionysiou DD. Innovative visible light-activated sulfur doped TiO2 films for water treatment. Applied Catalysis B: Environmental 2011;107(1-2):77-87. |
R833223 (Final) |
Exit |
|
Khan U, Benabderrazik N, Bourdelais AJ, Baden DG, Rein K, Gardinali PR, Arroyo L, O’Shea KE. UV and solar TiO2 photocatalysis of brevetoxins (PbTxs). Toxicon 2010;55(5):1008-1016. |
R833223 (Final) |
Exit Exit Exit |
|
Oehrle SA, Southwell B, Westrick J. Detection of various freshwater cyanobacterial toxins using ultra-performance liquid chromatography tandem mass spectrometry. Toxicon 2010;55(5):965-972. |
R833223 (Final) |
Exit Exit Exit |
|
Pelaez M, de la Cruz AA, Stathatos E, Falaras P, Dionysiou DD. Visible light-activated N-F-codoped TiO2 nanoparticles for the photocatalytic degradation of microcystin-LR in water. Catalysis Today 2009;144(1-2):19-25. |
R833223 (2008) R833223 (Final) |
Exit Exit Exit |
|
Pelaez M, Falaras P, Likodimos V, Kontos AG, de la Cruz AA, O’Shea K, Dionysiou DD. Synthesis, structural characterization and evaluation of sol-gel-based NF-TiO2 films with visible light-photoactivation for the removal of microcystin-LR. Applied Catalysis B: Environmental 2010;99(3-4):378-387. |
R833223 (Final) |
Exit Exit |
|
Pelaez M, de la Cruz AA, O’Shea K, Falaras P, Dionysiou DD. Effects of water parameters on the degradation of microcystin-LR under visible light-activated TiO2 photocatalyst. Water Research 2011;45(12):3787-3796. |
R833223 (Final) |
Exit Exit Exit |
|
Song W, Xu T, Cooper WJ, Dionysiou DD, de la Cruz AA, O’Shea KE. Radiolysis studies on the destruction of microcystin-LR in aqueous solution by hydroxyl radicals. Environmental Science & Technology 2009;43(5):1487-1492. |
R833223 (2008) R833223 (Final) |
|
|
Westrick JA, Szlag DC, Southwell BJ, Sinclair J. A review of cyanobacteria and cyanotoxins removal/inactivation in drinking water treatment. Analytical and Bioanalytical Chemistry 2010;397(5):1705-1714. |
R833223 (Final) |
Exit |
Supplemental Keywords:
water treatment, advanced oxidation, photolysis, material characterization, photooxidation, nanotechnology, green chemistry, environmental engineering, alternative materials, euthrophication, fate, toxicity, estuaries, product studies, nanoscience, analytical chemistry, organic chemistry.Relevant Websites:
http://www.greenwaterlab.com Exit
http://www.dep.state.fl.us/labs/hab_info.htm Exit
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.