Microplastic Particle Morphology Helps to Track Sources and Guide Management in the Great Lakes

Session: Poster session

Paul Helm, Ontario Ministry of the Environment and Climate Change, [email protected]
Erin Nicholls, MOECC, [email protected]
Courtney Miller, MOECC, [email protected]
Moyosore Lanisa, MOECC, [email protected]

Abstract

Microplastics (MPs) are emerging freshwater contaminants.  Our sampling of urban streams, wastewater effluents, and nearshore waters of the Great Lakes has shown that there are numerous types of MPs < 5 mm in size entering the lakes.  Typical reporting of MP sampling results usually includes abundances (counts per unit area or volume; or by mass) and grouping of types of MPs into broad categories such as fragments, film, foam, fibers, and pellets/beads. However, such broad categories may be insufficient for directing management actions for MP reductions and to measure the success of such actions. We present morphological characteristics of MPs which can be used to expand source-type categories. For example, rigid plastic particles resembling shavings, cuttings, and trimmings clearly generated by mechanical means, normally categorized as “fragments”, may be more indicative of commercial plastic activities.  These “commercial fragments” comprised a significant portion (>50%) of the up to 19 million MPs / sq. km found in Humber Bay along the waterfront of Toronto, Canada. Emissions of MPs from commercial sources may be a significant source to western Lake Ontario.  These findings form the basis for advice regarding strategies to reduce the occurrence of MPPs in the Great Lakes.

1. Keyword
microplastics

2. Keyword
Lake Ontario

3. Keyword
urban areas