Microplastic contamination in Lake Winnipeg, Canada

Microplastics are an emerging contaminant of concern in aquatic ecosystems. To better understand microplastic contamination in North American surface waters, we report for the first time densities of microplastics in Lake Winnipeg, the 11th largest freshwater body in the world. Samples taken 2014 to 2016 revealed similar or significantly greater microplastic densities in Lake Winnipeg compared with those reported in the Laurentian Great Lakes. Plastics in the lake were largely of secondary origin, overwhelmingly identified as fibres. We detected significantly greater densities of microplastics in the north basin compared to the south basin of the lake in 2014, but not in 2015 or 2016. Mean lake-wide densities across all years were comparable and not statistically different. Scanning electron microscopy with energy dispersive X-ray spectroscopy indicated that 23% of isolated particles on average were not plastic. While the ecological impact of microplastics on aquatic ecosystems is still largely unknown, our study contributes to the growing evidence that microplastic contamination is widespread even around sparsely-populated freshwater ecosystems, and provides a baseline for future study and risk assessments.

Philip J. Anderson, Sarah Warrack, Victoria Langen and al., Environmental Pollution, Volume 225, June 2017, Pages 223–231

The article

The role of public participation GIS (PPGIS) and fishermen’s perceptions of risk in marine debris mitigation in the Bay of Fundy, Canada

From nano-plastics to large sunken vessels, marine debris presents a threat to humans and ecosystems worldwide. Fishermen’s knowledge of the sources of, and risks posed by medium to large debris derived from fishing, aquaculture, and other marine industries provides important context for debris mitigation. Public participation geographic information systems (PPGIS) can address these risks by integrating subjective and objective spatial data on human and environmental impacts and risks. We integrated fishermen’s perceptions and experiences with marine debris with spatial data using PPGIS. We developed a georeferenced database of fishermen’s experiences with marine debris, collected during focus groups and at various other meetings in Southwest New Brunswick. This layer was used to integrate baseline data with subjective perceptions of the ecological, economic, and navigational risks associated with marine debris in the Bay of Fundy, Canada. We also documented the physical, technical, political, and regulatory challenges to marine debris mitigation. These challenges highlight the social and environmental processes that complicate any projects that attempt to develop uncontested spatial representations of marine debris. Finally, we discuss the potential of PPGIS to address these challenges by fostering communication, coordinating various marine activities, helping stakeholders set priorities for clean-up, and implementing collaborative clean-up projects.

Allain J. Barnett, Melanie G. Wiber, Michael P. Rooney, Donna G. Curtis Maillet, Ocean & Coastal Management, Volume 133, December 2016, Pages 85–94

The article

Microplastics in aquatic environments: Implications for Canadian ecosystems

Microplastics have been increasingly detected and quantified in marine and freshwater environments, and there are growing concerns about potential effects in biota. A literature review was conducted to summarize the current state of knowledge of microplastics in Canadian aquatic environments; specifically, the sources, environmental fate, behaviour, abundance, and toxicological effects in aquatic organisms. While we found that research and publications on these topics have increased dramatically since 2010, relatively few studies have assessed the presence, fate, and effects of microplastics in Canadian water bodies. We suggest that efforts to determine aquatic receptors at greatest risk of detrimental effects due to microplastic exposure, and their associated contaminants, are particularly warranted. There is also a need to address the gaps identified, with a particular focus on the species and conditions found in Canadian aquatic systems. These gaps include characterization of the presence of microplastics in Canadian freshwater ecosystems, identifying key sources of microplastics to these systems, and evaluating the presence of microplastics in Arctic waters and biota.

Julie C. Anderson, Bradley J. Park, Vince P. Palace, Environmental Pollution, Volume 218, November 2016, Pages 269–280

The article

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

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.

Anika Ballent, Patricia L. Corcoran, Odile Madden, Paul A. Helm, Fred J. Longstaffe, Marine Pollution Bulletin, Volume 110, Issue 1, 15 September 2016, Pages 383–395

The article