Hidden plastics of Lake Ontario, Canada and their potential preservation in the sediment record

Large microplastic particles in sediments of tributaries of the River Thames, UK – Abundance, sources and methods for effective quantification

“…Of the particles remaining unfloated throughout the sorting process, a number were identified to be dense composites of road-marking paints, aggregates, a painted coating on a dense particle or high density mineral-polymer mixtures (Corcoran et al, 2015). These materials are composites of polymer resin, thermoplastic, bitumen and pigment (often with incorporated glass beads for reflectivity) (Conserva and Dupont, 2011; National Association of City Transportation Officials, 2014).…”

Impacts of temperature and selected chemical digestion methods on microplastic particles

“…Various solutions have been used that do not alter microplastic polymers, including hypersaline sodium chloride (NaCl; [15,31], sodium iodide [23], and sodium polytungstate [7,8]. However, some of these solutions (e.g., NaCl) are not effective for higher density polymers [21], and fouling by organic and inorganic materials can alter microplastic particle densities, requiring subsequent manual sorting [8].…”

Sources and sinks of microplastics in Canadian Lake Ontario nearshore, tributary and beach sediments

“…Rivers and urban tributaries, however, have been shown to be major transport pathways for microplastics and macroplastics (Moore et al, 2011;Gasperi et al, 2014;Lechner et al, 2014;Rech et al, 2014;Zhao et al, 2014;Corcoran et al, 2015;Naidoo et al, 2015). Whereas buoyant materials are transported on surface waters (Gasperi et al, 2014), non-buoyant materials are transported along the tributary bed (Moore et al, 2011;Morritt et al, 2014).…”

“…Several countries, including Canada and the United States, have since begun the process of banning the sale of cosmetic products containing microplastics. Polyethylene (PE) and polypropylene (PP), often used in the production of cosmetic microplastics, have densities less than that of fresh water, but have nonetheless been regularly identified in submerged sediments (Claessens et al, 2011;Vianello et al, 2013;Corcoran et al, 2015). The study of microplastics in sediment is therefore needed for a comprehensive understanding of microplastics contamination in the Laurentian Great Lakes.…”

“…Microplastics pollution has been reported from Great Lakes surface waters (Eriksen et al, 2013), along shorelines (Zbyszewski and Corcoran, 2011;Zbyszewski et al, 2014;Corcoran et al, 2015) and in offshore lake bottom sediments , but its presence in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 Ballent, Anika Manuscript page 2 subsurface sediments of nearshore regions and tributaries is still largely unknown (Driedger et al, 2015). Allan et al (2013) modeled current environmental stressors affecting the Great Lakes and found that cumulative stress levels were greatest in nearshore regions and generally decreased with distance from the shore.…”