Research and Publications

This report summarizes the findings of a research project conducted by the Ohio Sea Grant College Program (OSG) in the fall of 2016. Funding for the project was provided by the National Oceanic and Atmospheric Administration (NOAA) Marine Debris Program through an award to the City of Cleveland Mayor’s Office of Sustainability. OSG was subcontracted by Thunder Tech Inc., a private marketing firm located in Cleveland, Ohio, to conduct applied research to inform a social marketing campaign focused on reducing plastic marine debris. The results will be used by the City of Cleveland and Thunder Tech Inc. to develop a social marketing campaign designed to support desired behaviors regarding the use and proper disposal of plastic bags, water bottles, and cigar tips.

The distribution patterns, compositions and textures of plastic debris along the Lake Erie and St. Clair shorelines were studied in order to determine the roles of potential source locations, surface currents, and shoreline types in the accumulation of plastic litter. The results were compared with those previously determined from Lake Huron, where abundant plastic pellets characterize the southeastern shoreline. Lake Erie and St. Clair shorelines contained some pellets, but were mainly characterized by plastic fragments and intact products, respectively. The potential sources for the pellets include spillage within factories or during transport and off-loading; whereas intact products were derived from urban waste. Once entering the lake environment, low density floating polymers such as polyethylene and polypropylene were degraded by UVB radiation at either the water surface or once deposited on shorelines. Mechanical degradation by wave action and/or sand abrasion fragmented intact products into cm-size particles. Certain textures identified on the surfaces of plastic particles could be related to the nature of the depositional environment. Plastics sampled from infrequently visited muddy, organic-rich shorelines were characterized by more adhering particles and less mechanical pits than those from sandy shorelines.In terms of relative distribution, the Lake St. Clair shoreline contained the least amount of plastic debris of the three lakes. This is a function of the breakwaters and retaining walls built along Lake St. Clair, which replace natural sandy or muddy sinks for floating polymers. This study represents the first detailed record of plastics distribution along multiple, but related fresh water shorelines.

Marine debris is a persistent problem in many coastal areas of the United States. There are a variety of potential economic losses associated with marine debris, including effects on commercial fisheries, effects on waterfront property values, costs incurred by local governments and volunteer organizations to remove and dispose of marine debris, and more general “existence” values reflecting the public’s preference for a clean environment. This study evaluates two types of economic loss that result from the effects of marine debris on beach recreation: the loss of recreational value to beach visitors, and the regional economic impact from reduced spending on beach visits in a particular region. Beach studies in the Great Lakes were conducted in Ohio.

A study was completed in the northern part of Lake Erie, Ontario to determine the concentrations and distribution of microplastics. Following density separation and microscopic analysis of 29 samples, a total of 1178 microplastic particles were identified. Thirteen nearshore samples contained 0–391microplastic particles per kg dry weight sediment (kg−1), whereas 4 tributary samples contained 10–462 kg−1 and 12 beach samples contained 50–146 kg−1. The highest concentrations of nearshore microplastics were from near the mouths of the Detroit River in the western basin and the Grand River in the eastern basin, reflecting an urban influence. The highest microplastic concentrations in beach samples were determined from Rondeau Beach in the central basin where geomorphology affects plastics concentration. The Welland Canal sample in the eastern basin contained the greatest concentration of microplastics of the tributary samples, which is consistent with high population density and shipping traffic. The overall abundance of microplastic in northern Lake Erie nearshore, tributary and beach samples is 6 times lower than in sediment sampled from northern Lake Ontario. The nearshore and beach sample results potentially reflect the transport patterns of floating plastics modeled for Lake Erie, which predict that the majority of plastic particles entering the lake are transported to southern shoreline regions rather than northern areas.

The NOAA Marine Debris Program has developed standardized, statistically valid methodologies for conducting rapid assessments of the debris material type and quantity present in a monitored location. The monitoring guidelines in this document focus on abundance, types, and concentration on shorelines, in surface waters, during visual surveys at sea, and in the benthos.

The purpose of this project was to quantify microplastic loads at single sites on selected beaches at a continental scale to better understand microplastic distribution. Six sites were sampled in the Great Lakes Region.

Given the growing saliency of plastic marine debris, and the impact of plastics on beaches and aquatic environments in the Laurentian Great Lakes, applied research is needed to support municipal and nongovernmental campaigns to prevent debris from reaching the water's edge. This study addresses this need by examining the barriers and benefits to positive behavior for two plastic debris items in northeast Ohio's Lake Erie basin: plastic bags and plastic water bottles. An online survey is employed to gather data on the use and disposal of these plastic items and to solicit recommendations on how to positively change behavior to reduce improper disposal. Results support a ban on plastic bags and plastic water bottles, with more enthusiasm for a bag ban. Financial incentives are also seen as an effective way to influence behavior change, as are location-specific solutions focused on education and outreach.

Resistivity of plastic litter to chemical weathering, mechanical erosion, and biological degradation poses a critical environmental threat. Plastic debris has increased in abundance over the past several decades along shorelines and at sea, where organisms mistake small particles including plastic pellets as a potential food supply. These pellets have been shown to adsorb persistent organic pollutants such as PCBs, which may endanger the organism and become ingested higher in the food chain. Although several studies have been conducted to determine the amount and effects of plastics pollution in marine environments, relatively little is known concerning fresh water plastics pollution. This study represents the first detailed examination of the distribution, types, and physical and chemical degradation processes of plastic particles in a fresh water setting. In conducting field surveys along the shoreline of Lake Huron, Canada, we were able to ascertain that the total number of pellets over multiple sampling localities comprise 94% of plastic debris. The majority of the pellets were found proximal to an industrial sector along the southeastern margin of the lake and their abundance steadily decreased northward, following the dominant lake current patterns. Laboratory analyses using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy indicate predominant mechanical abrasion textures, including grooves, gauges, pits, and flakes, and less common chemical weathering features such as linear and crescentic fractures that developed from shrinkage during subaerial exposure. The predominant type of plastic, polyethylene, appears to be much more resistant to chemical weathering than polypropylene, as indicated by oxidation peaks on FTIR spectra suggesting that polypropylene degrades more readily under natural conditions on freshwater beaches.

Investigations of microplastic abundances in freshwater environments have become more common in the past five years, but few studies concern the factors that control the distribution of microplastics in river systems. We sampled benthic sediment from 34 stations along the Thames River in Ontario, Canada, to determine the influence of land use, grain size, river morphology, and relative amount of organic debris on the distribution of microplastics. Once counted and characterized for shape, color, and size, microplastic abundances were normalized to the results from Fourier transform infrared spectroscopy on randomly selected particles. The results indicate that 78% of the fragments and only 33% of the fibers analyzed were plastic. The normalized microplastic quantities ranged from 6 to 2444 particles per kg of dry weight sediment (kg−1  dw). The greatest number of microplastics were identified in samples of the fi nest grain sizes and with the greatest amount of organic debris. Although there was no significant difference between microplastic abundances in urban versus rural locations, the average microplastic count for urban samples was greater (269 vs 195 kg−1  dw). In terms of river morphology, samples from along straight courses of the river contained fewer microplastics than samples from inner and outer bends. Overall abundances confirm how rivers contain a significant number of plastic particles and thus may be major conduits of microplastics to lake and ocean basins.

Microplastics are a source of environmental pollution resulting from degradation of plastic products and spillage of resin pellets. We report the amounts of microplastics from various sites of Lake Ontario and evaluate their potential for preservation in the sediment record. A total of 4635 pellets were sampled from the Humber Bay shoreline on three sampling dates. Pellet colours were similar to those from the Humber River bank, suggesting that the river is a pathway for plastics transport into Lake Ontario. Once in the lake, high density microplastics, including mineral-polyethylene and mineral-polypropylene mixtures, sink to the bottom. The minerals may be fillers that were combined with plastics during production, or may have adsorbed to the surfaces of the polymers in the water column or on the lake bottom. Based on sediment depths and accumulation rates, microplastics have accumulated in the offshore region for less than 38 years. Their burial increases the chance of microplastics preservation. Shoreline pellets may not be preserved because they are mingled with organic debris that is reworked during storm events.

Marine debris is a pervasive pollution problem that impacts all corners of the globe. Sometimes, debris ends up in places that require innovative thinking in order to remove. Check out some of these projects that implemented unique or developed best management practices for removing debris from the environment.

Microplastics contamination of Lake Ontario sediments is investigated with the aim of identifying distribution patterns and hotspots in nearshore, tributary and beach depositional environments. Microplastics are concentrated in nearshore sediments in the vicinity of urban and industrial regions. In Humber Bay and Toronto Harbour microplastic concentrations were consistently 500 particles per kg dry sediment. Maximum concentrations of ~28,000 particles per kg dry sediment were determined in Etobicoke Creek. The microplastic particles were primarily fibres and fragments 2 mm in size. Both low- and high-density plastics were identified using Raman spectroscopy. We provide a baseline for future monitoring and discuss potential sources of microplastics in terms of how and where to implement preventative measures to reduce the contaminant influx. Although the impacts of microplastics contamination on ecosystem health and functioning is uncertain, understanding, monitoring and preventing further microplastics contamination in Lake Ontario and the other Great Lakes is crucial.