Sourcing of microplastics entering Lake Winnipeg, Manitoba, Canada
| dc.contributor.author | Cunningham, Tekla | |
| dc.contributor.examiningcommittee | Brink, Kirstin (Earth Sciences) | |
| dc.contributor.examiningcommittee | Wang, Feiyue (Environment and Geography) | |
| dc.contributor.supervisor | Fayek, Mostafa | |
| dc.date.accessioned | 2024-09-12T14:57:46Z | |
| dc.date.available | 2024-09-12T14:57:46Z | |
| dc.date.issued | 2024-08-15 | |
| dc.date.submitted | 2024-08-15T17:14:10Z | en_US |
| dc.degree.discipline | Earth Sciences | |
| dc.degree.level | Master of Science (M.Sc.) | |
| dc.description.abstract | The accumulation of plastic pollution is a pressing issue, especially the presence of microplastics in the environment. Microplastics are ubiquitous in the environment, however a research gap exists in understanding the sources of microplastics in freshwater environments. The lack of standardized methodologies for the collection, quantification, and identification of microplastics hinders our understanding of the sources and amounts of microplastics in the environment. This thesis evaluates the potential of carbon and hydrogen stable isotope (δ13C and δ2H) and elemental (%C and %H) analysis to identify the polymer type of microplastics. The polymer type of microplastics provides important information on their source. Commercial plastic products (n = 53) from six different polymer types were used to create a database of characteristic δ13C, δ2H, %C, and %H values for each polymer type. Environmental microplastics (n = 18) of unknown polymer types were also analyzed and their values were compared to the characteristic values for each polymer type in the database. Fourier transform infrared spectroscopy was used to confirm the identification of the polymer type of the unknown microplastics. The combination of the δ2H and %H values was best able to distinguish the different polymer types and was most useful for identifying the unknown microplastics. The identification of the unknown microplastics using their δ2H and %H values correlated strongly with identifications using FTIR, confirming that this represents a novel method that can be used to identify the polymer type of microplastics. Because it is a quantitative analysis, it is more attractive than other qualitative methods of identifying the polymer type of microplastics. Additionally, this thesis investigates spatial and temporal trends in microplastic concentrations in the Red River in Manitoba. Surface water samples were collected from nine sites in the spring, summer, and fall of 2022 to evaluate spatial and temporal trends in microplastic concentrations. Microplastics were found in all samples, with concentrations ranging from 70.0 to 268.7 particles m-3. Increased flow rates and stormwater runoff in the spring likely influenced seasonal variations observed in microplastic concentrations. Stormwater runoff, combined sewage overflows, and agricultural runoff are potential sources of microplastics to the Red River. | |
| dc.description.note | October 2024 | |
| dc.identifier.uri | http://hdl.handle.net/1993/38575 | |
| dc.language.iso | eng | |
| dc.rights | open access | en_US |
| dc.subject | Microplastics | |
| dc.subject | Freshwater microplastics | |
| dc.subject | Stable isotope analysis | |
| dc.subject | Microplastics identification | |
| dc.subject | Lake Winnipeg | |
| dc.subject | Red River | |
| dc.title | Sourcing of microplastics entering Lake Winnipeg, Manitoba, Canada | |
| dc.type | master thesis | en_US |
| local.subject.manitoba | yes | |
| oaire.awardTitle | University of Manitoba Graduate Fellowship | |
| project.funder.identifier | https://doi.org/10.13039/100010318 | |
| project.funder.name | University of Manitoba |