Benthic plastic debris in marine and fresh water environments

Abstract

This review provides a discussion of the published literature concerning benthic plastic debris in ocean, sea, lake, estuary and river bottoms throughout the world. Although numerous investigations of shoreline, surface and near-surface plastic debris provide important information on plastic types, distribution, accumulation, and degradation, studies of submerged plastic debris have been sporadic in the past and have become more prominent only recently. The distribution of benthic debris is controlled mainly by combinations of urban proximity and its association with fishing-related activities, geomorphology, hydrological conditions, and river input. High density plastics, biofouled products, polymers with mineral fillers or adsorbed minerals, and plastic-metal composites all have the potential to sink. Once deposited on the bottoms of water basins and channels, plastics are shielded from UV light, thus slowing the degradation process significantly. Investigations of the interactions between benthic plastic debris and bottom-dwelling organisms will help shed light on the potential dangers of submerged plastic litter.

The geological cycle of plastics and their use as a stratigraphic indicator of the Anthropocene

“…beaches), the limited variability of topography and process, and the environmental significance of the phenomenon, has encouraged more systematic study. It is clear that plastics are widely distributed, both as macroplastics and as microplastics, to the extent that they can be retrieved from most sea floor sediment samples in most parts of the world (Browne et al, 2011;Woodall et al, 2014;Corcoran, 2015). Overall, therefore, plastics, and particularly microplastics, may be an effective means to recognize terrestrial and marine sediments deposited since the mid-twentieth century.…”

“…turbidity and contour currents) in deep water before finally being deposited. However, low-density plastics have also been found in lake-bottom sediments, having been deposited as a result of density increase by mineral fillers during production, or mineral adsorption while in the water column Corcoran, 2015). It is also being increasingly realized that the transport of plastics through the water column is often mediated biologically (see below) because microbial films rapidly develop on submerged microplastics, and change their buoyancy (Lobelle and Cunliffe, 2011).…”

Microplastic-Associated Biofilms: A Comparison of Freshwater and Marine Environments

“…Identifying such taxa and investigating their ability to biodegrade different plastic types, additives, and polymer-sorbed compounds are of primary importance to understanding the environmental residence times of plastic waste. Research in this area should focus on habitats functioning as sinks for the accumulation of plastic, including sediments [3][4][5]27]. To obtain a complete understanding of the biodegradability of different materials and compounds, there is a need to combine laboratory-based experiments with field-based measurements of plastic degradation in both freshwater and marine environments.…”

“…They are encountered within the water column and sediments, with the latter functioning as a sink for the accumulation of plastic waste [3][4][5]. Most plastic litter originates from land-based activities, with wastewater treatment plant (WWTP) and inland waters comprising an important route through which this pollution reaches marine environments [6,7].…”

A Methodology for Measuring Microplastic Transport in Large or Medium Rivers

“…They can also become higher density polymers when mineral fillers are added during production [27]. Plastic particles change in size and density by aggregation or by the growth of biofilms [28][29][30], and flow turbulence moves them within rivers [31].…”