Grant: Discovery Grants Program - Individual

Plastics remain in the environment for hundreds to thousands of years. Wastewater treatment plants are the main pathways of microplastic pollution to fresh waters and agricultural soils. Currently, there is very limited knowledge on the quantities of nano (25 mm) in wastewater, their fate and removal during wastewater and sludge treatment processes, how they impact biological treatment processes, and how they are impacted by the physical, chemical, and biological treatment. Treatment processes may change the size, density, shape, and surface characteristics of plastics through erosion or biofilm growth and impact their fate and removal. Plastics leach out toxic resins that may adversely affect biological treatment and the microbial population. Disinfection and advanced oxidation processes may impact the polymer structure and release nanoplastics in wastewater. Finally, there is a need for innovative approaches to microplastic removal during wastewater and sludge treatment. Therefore, research is needed to understand the occurrence, fate, removal, and impact of micro and nanoplastics during wastewater and sludge treatment, improve the performance of treatment processes for their removal, and find cost-effective ways to achieve this and our research program aims to achieve these goals. Wastewater treatment plants will be studied, including those in urban cities, industrial areas, and rural communities. Samples will be collected from raw wastewater entering the plants and throughout the wastewater and sludge treatment processes. In addition, lab-scale reactors will be operated to enable controlled experiments. Identification, characterization, and quantification of plastics will be done using leading-edge scientific methods and instruments available in our labs. Our focus will be on detecting smaller microplastics, microfibers, and nanoplastics and understanding their impacts. Canadians throw away over 3 million tonnes of plastic waste every year and only 9% of these plastics are recycled while the rest largely end up in landfills and some in water environments. The knowledge generated from this research program will provide the necessary information to improve the performance of wastewater treatment plants for capturing microplastics and microfibers and minimize their discharge to water and soil environments in a cost-effective way. Furthermore, the research will provide critically important information to government agencies to develop policies on reducing and controlling microplastic pollution. Microplastics have been shown to have adverse environmental and health impacts and action is needed to reduce the microplastics and nanoplastics released from wastewater treatment plants.