Treatment of Antiviral Drugs in Wastewater Using Advanced Oxidation Processes - Ozonation of Oseltamivir Phosphate

  • Author / Creator
    Shawn Jansen van Beek
  • While wastewater treatment facilities are designed to remove contaminants from water before it returns to the environment, unfortunately, not all of these facilities are effective in the removal of micropollutants (MPs). Antiviral drugs are a class of MPs that have become an area of concern due to their increased use and potential for negative impacts on the environment. An extensive literature review was undertaken to analyze the treatment methods, detection methods, and environmental fate of antiviral drugs to provide information on areas requiring further research. Treatment processes such as filtration, sedimentation, aerobic biological treatment, and anaerobic biological treatment were found to be generally unsuccessful for the removal of antiviral drugs. Advanced oxidation processes (AOPs) such as ozonation, UV/persulfate, and electro-oxidation processes showed significantly more promising results in the removal of antiviral drugs in water. However, there is a lack of some crucial information on AOPs treatment of antiviral drugs which including the disinfection byproducts (DBPs) that are produced which have the potential to possess toxic qualities as well. The environmental fate of antiviral drugs and their DBPs is under-researched with little information known on their properties such as adsorption, infiltration, or solubility, leaving a potential for accumulation that is not well understood. The effects of antiviral drugs on a variety of species is also unknown, with very few studies examining even the most directly affected aquatic wildlife. Bench-scale studies examined the treatment of oseltamivir phosphate (OSP) using ozone (O3) as the oxidant. Batch experiments were done to determine the first and second-order rate constants of the reaction between O3 and OSP and ozone was found to be effective for the removal of OSP in buffered water (H2O) with >99% removal of OSP. The impact of pH and various ionic species commonly found in wastewater were examined for effects on the rate of degradation, both of which resulted in either minor or no change to the reaction rate. The ozonation of OSP in secondary effluent (SE) was required to prove effectiveness of the ozonation in real-life matrices and was able to remove >99% of the oseltamivir within 30 seconds with a 10:1 molar ratio of O3 to OSP. Thirteen DBPs resulting from the ozonation of OSP were monitored with respect to time and structures were predicted, these were characterized into categories of increasing concentration with respect to ozone exposure, decreasing concentration, and unchanging concentration. Finally, the acute toxicity towards V. fischeri and the genotoxicity of both treated and untreated OSP samples were monitored; these tests showed that both ozonated and non-ozonated OSP samples in buffered and real wastewater matrices did not result in an increase in toxicity. This study overall suggests that ozonation has the potential to be a significant improvement for the treatment of OSP in sewage treatment plants.

  • Subjects / Keywords
  • Graduation date
    Fall 2021
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.