1) Method Development and Harmonization
Air Sampling
Effective atmospheric sampling methods for MPs have not yet been comprehensively tested. We are investigating five sampling methods for comparative analysis, using robust quality assurance and quality control measures:
- Passive: Moss bags and adhesive slides,
- Active: 24-hour active air pump,
- Deposition: Bulk Bottle and Funnel, Precipitation only sampler.
Schematic of Wet only, BF, HV, Moss, and Slides – deposition versus ambient.
Water Sampling
Urban streams and rivers are important pathways for MPs and other anthropogenic particles (e.g., plastic pellets, foams, tire wear) to enter waterbodies. Well-tested, robust, and replicable sampling are needed to obtain representative and comparable data for use in loadings analysis, benchmarking, source tracking, etc. We conducted a systematic investigation of typical stream sampling procedures to assess sampling efficiency during both low and high flow (rain).
Tested sampling methods include nets, pumps, grabs, and combinations of these.
Tested sampling methods include nets, pumps, grabs, and combinations of these.
Processing and Analysis
In samples with high amounts of organic matter and other interfering matrices, common MPs extraction protocols are not necessarily effective. In addition, some polymers are susceptible to degradation during the digestion process. Therefore, we have undertaken a systematic investigation of the effectiveness of extraction procedures to more completely remove the unwanted matrix while balancing the retention of MPs, using complex urban stormwater runoff samples as a test matrix. We tested sequential combinations of oxidative-alkaline protocols to the complex organic matrix from urban runoff samples and to particles comprised of a range of polymers and a variety of sizes and shapes (with and without interfering matrices).
We develop methods for chemical analysis of MPs sampled from various environmental matrices (e.g., air, water, snow) using (1) Laser Direct Infrared (LDIR), a relatively novel instrument used for analysis of MPs and (2) micro-Fourier Transform Infrared Spectroscopy, capable of automated spectroscopic analysis.
We develop methods for chemical analysis of MPs sampled from various environmental matrices (e.g., air, water, snow) using (1) Laser Direct Infrared (LDIR), a relatively novel instrument used for analysis of MPs and (2) micro-Fourier Transform Infrared Spectroscopy, capable of automated spectroscopic analysis.
Reporting Guidelines
To grapple with the diversity of microplastics and the need for inter-study data comparability, the community of practice has been working towards harmonized categorization schemes, size-based definitions, and reporting guidelines. We applied a fit for purpose perspective to illustrate its utility in the categorization of microplastics shapes and help guide efforts to harmonize morphological classifications.
Relevant papers:
Yu, J. T., Diamond, M. L., & Helm, P. A. (2023). A fit‐for‐purpose categorization scheme for microplastic morphologies. Integrated Environmental Assessment and Management, 19(2), 422-435.
Yu, J. T., Diamond, M. L., & Helm, P. A. (2023). A fit‐for‐purpose categorization scheme for microplastic morphologies. Integrated Environmental Assessment and Management, 19(2), 422-435.
2) Source Identification and Loads in Urban Regions
To enhance and focus localized reduction efforts, we investigate source and activity-specific contributions to MPs contamination in urban regions, particularly in the Greater Toronto Area and the larger Laurentian Great Lakes watersehds. We examine MPs in close proximity to densely populated areas with strong industrial-plastics-sector presence, where alongshore currents distribute high concentration inputs from rivers and wastewater discharges. We aim to inform source-specific localized actions targeting specific sources and pathways of the plastic to waterways of that region are needed
Relevant papers:
Yu, J.T., Diamond, M. L., Helm, P. A. (2023). Source-Specific Categorization of Microplastics in Nearshore Surface Waters of the Great Lakes. Submitted.
Akhbarizadeh, R., Yu, J. T., Ead, L., Nicholls, E., Thibeau, J., Lanisa, M., Wakai., M., Marquez, A., Sims, A., Diamond, M. L., Helm, P. A. (2023). Reductions of plastic microbeads from personal care products in wastewater effluents and lake waters following regulatory actions. Submitted.
Yu, J.T., Diamond, M. L., Helm, P. A. (2023). Source-Specific Categorization of Microplastics in Nearshore Surface Waters of the Great Lakes. Submitted.
Akhbarizadeh, R., Yu, J. T., Ead, L., Nicholls, E., Thibeau, J., Lanisa, M., Wakai., M., Marquez, A., Sims, A., Diamond, M. L., Helm, P. A. (2023). Reductions of plastic microbeads from personal care products in wastewater effluents and lake waters following regulatory actions. Submitted.
3) Sinks: Remote Northern Communities and the High Arctic
As polar regions are already highly sennsitive due to climate related stressors, the emerging threat of MPs and their associated chemicals has prompted the Arctic Monitoring and Assessment Program (AMAP) to mandate multi-compartment monitoring and assessment of plastic litter and microplastics in the Arctic.
We collaborate with Environment and Climate Change Canada and their northern community partners through multiple research projects to investigate the presence and distribution of MPs in sediment, air, snow, and water in the Canadian Northern Territories and Arctic Archipelago.
Our main objective is to better understand the relative contributions of locally emitted MPs and long-range transport via air and water currents in these remote, sparsely inhabited regions. We test the hypothesis that complex mixtures of MPs undergo fractionation during long-range transport from source to sink regions.
We collaborate with Environment and Climate Change Canada and their northern community partners through multiple research projects to investigate the presence and distribution of MPs in sediment, air, snow, and water in the Canadian Northern Territories and Arctic Archipelago.
Our main objective is to better understand the relative contributions of locally emitted MPs and long-range transport via air and water currents in these remote, sparsely inhabited regions. We test the hypothesis that complex mixtures of MPs undergo fractionation during long-range transport from source to sink regions.
Relevant papers:
Athey, S. N., Adams, J. K., Erdle, L. M., Jantunen, L. M., Helm, P. A., Finkelstein, S. A., & Diamond, M. L. (2020). The widespread environmental footprint of indigo denim microfibers from blue jeans. Environmental Science & Technology Letters, 7(11), 840-847.
Adams, J. K., Dean, B. Y., Athey, S. N., Jantunen, L. M., Bernstein, S., Stern, G., ... & Finkelstein, S. A. (2021). Anthropogenic particles (including microfibers and microplastics) in marine sediments of the Canadian Arctic. Science of the Total Environment, 784, 147155.
Athey et al. 2023. Fractionation of anthropogenic particles (microplastics and microfibers) along a 2,200-km transect of Canadian sediments. Submitted
Athey, S. N., Adams, J. K., Erdle, L. M., Jantunen, L. M., Helm, P. A., Finkelstein, S. A., & Diamond, M. L. (2020). The widespread environmental footprint of indigo denim microfibers from blue jeans. Environmental Science & Technology Letters, 7(11), 840-847.
Adams, J. K., Dean, B. Y., Athey, S. N., Jantunen, L. M., Bernstein, S., Stern, G., ... & Finkelstein, S. A. (2021). Anthropogenic particles (including microfibers and microplastics) in marine sediments of the Canadian Arctic. Science of the Total Environment, 784, 147155.
Athey et al. 2023. Fractionation of anthropogenic particles (microplastics and microfibers) along a 2,200-km transect of Canadian sediments. Submitted
