Plastic pollution in freshwater ecosystems: macro-, meso-, and microplastic debris in a floodplain lake

Abstract

Plastic pollution is considered an important environmental problem by the United Nations Environment Programme, and it is identified, alongside climate change, as an emerging issue that might affect biological diversity and human health. However, despite research efforts investigating plastics in oceans, relatively little studies have focused on freshwater systems. The aim of this study was to estimate the spatial distribution, types, and characteristics of macro-, meso-, and microplastic fragments in shoreline sediments of a freshwater lake. Food wrappers (mainly polypropylene and polystyrene), bags (high- and low-density polyethylene), bottles (polyethylene terephthalate), and disposable Styrofoam food containers (expanded polystyrene) were the dominant macroplastics recorded in this study. Contrary to other studies, herein macroplastic item surveys would not serve as surrogates for microplastic items. This is disadvantageous since macroplastic surveys are relatively easier to conduct. Otherwise, an average of 25 mesoplastics (mainly expanded polystyrene) and 704 microplastic particles (diverse resins) were recorded per square meter in sandy sediments. Comparisons with other studies from freshwater and marine beaches indicated similar relevance of plastic contamination, demonstrating for the first time that plastic pollution is a serious problem in the Paraná floodplain lakes. This study is also valuable from a social/educational point of view, since plastic waste has been ignored in the Paraná catchment as a pollutant problem, and therefore, the outcome of the current study is a relevant contribution for decision makers.

Plastic debris in rivers

“…The percentages and most common products are assessed and calculated based on data from Schwarz et al (2019), Textileworld (2019), and PlasticsEurope (2018 For plastic sizes, consistent terming and dimensions lack throughout plastic pollution studies. Most used terms are nanoplastics, microplastics, mesoplastics, macroplastics, and megaplastics (Blettler et al, 2017;Frias & Nash, 2019;Lebreton et al, 2018). Dividing plastics by size is still useful in terms of determining the source and to assess the final environmental impact.…”

A temporal sediment record of microplastics in an urban lake, London, UK

“…Microplastics (including synthetic fibres) \ 5 mm in size are of interest due to the likelihood of ingestion by freshwater organisms and, because they have large specific surface area, their potential for adsorption and leaching of associated contaminants and additives (Lobelle and Cunliffe 2011;Sanchez et al 2014;Faure et al 2015;Näkki et al 2017). Pellets and 'microbeads' specifically manufactured as microplastic forms (primary microplastics) may be found in freshwaters subject to large inputs of industrial drainage or effluent (Castañeda et al 2014;Lechner et al 2014;Corcoran et al 2015;Driedger et al 2015;Baldwin et al 2016;Horton et al 2017a;Horton and Dixon 2018), although secondary microplastics (derived from the breakdown of larger plastic items) dominate in freshwater sediments subject to more diffuse plastic waste sources (Free et al 2014;Driedger et al 2015;Faure et al 2015;Zhang et al 2016;Blettler et al 2017;Matsuguma et al 2017;Sruthy and Ramasamy 2017;Imhof et al 2018).…”

“…Microplastics have been found in lake sediments, with inputs linked to urbanization, industrial activities and wastewater influences (Castañeda et al 2014;Corcoran et al 2015;Driedger et al 2015;Su et al 2016;Blettler et al 2017), but high-resolution sediment evidence of the historical incorporation of microplastics in lake sediments, indeed in any codated or cross-correlated aquatic/estuarine sediment, is surprisingly rare (Cundy et al 1998;Corcoran et al 2015;Matsuguma et al 2017;Willis et al 2017). Previous age/depth measurements of lake-sediment microplastic abundance were estimated either by comparison with historical trends of other contaminants or by correlation with other cores (Corcoran et al 2015;Matsuguma et al 2017).…”

An evaluation of the River-OSPAR method for quantifying macrolitter on Dutch riverbanks

“…And last, the protocols that examine both macro and micro sized litter (e.g. Blettler et al, 2017). It must be noted that not all papers that characterized microplastics were taken into consideration for analysis.…”