Microplastic pollution identified in deep-sea water and ingested by benthic invertebrates in the Rockall Trough, North Atlantic Ocean

Abstract

Microplastics are widespread in the natural environment and present numerous ecological threats. While the ultimate fate of marine microplastics are not well known, it is hypothesized that the deep sea is the final sink for this anthropogenic contaminant. This study provides a quantification and characterisation of microplastic pollution ingested by benthic macroinvertebrates with different feeding modes (Ophiomusium lymani, Hymenaster pellucidus and Colus jeffreysianus) and in adjacent deep water > 2200 m, in the Rockall Trough, Northeast Atlantic Ocean. Despite the remote location, microplastic fibres were identified in deep-sea water at a concentration of 70.8 particles m, comparable to that in surface waters. Of the invertebrates examined (n = 66), 48% ingested microplastics with quantities enumerated comparable to coastal species. The number of ingested microplastics differed significantly between species and generalized linear modelling identified that the number of microplastics ingested for a given tissue mass was related to species and not organism feeding mode or the length or overall weight of the individual. Deep-sea microplastics were visually highly degraded with surface areas more than double that of pristine particles. The identification of synthetic polymers with densities greater and less than seawater along with comparable quantities to the upper ocean indicates processes of vertical re-distribution. This study presents the first snapshot of deep ocean microplastics and the quantification of microplastic pollution in the Rockall Trough. Additional sampling throughout the deep-sea is required to assess levels of microplastic pollution, vertical transportation and sequestration, which have the potential to impact the largest global ecosystem.

Microplastic ingestion ubiquitous in marine turtles

“…Many potential microplastic fibres from the FT-IR subsample in this study were identified with high spectral matches as cellulose-based particles, despite their appearance under visual examination as microplastics. Indeed, this has begun to be reported elsewhere within the literature (Cai et al, 2017;Courtene-Jones, Quinn, Gary, Mogg, & Narayanaswamy, 2017;Remy et al, 2015). For example, blue cotton indigo fibres from samples of waste water treatments plants can show close visual similarity to polyacrylic fibres (Dyachenko, Mitchell, & Arsem, 2017;Silva et al, 2018).…”

Microparticles in Table Salt: Levels and Chemical Composition of the Smallest Dimensional Fraction

“…The presence of microplastic at different levels of the aquatic trophic web was documented by the literature [18]; D'Alessandro et al [19] reported relationships among the plastic litter, chemical pollutants and observed benthic biodiversity. Microplastic is recorded in edible seafood and mariculture products [20,21] such as pelagic fish species [22], benthic species [15,23], bivalves [24][25][26], holothurians [27], and marine mammals [28] as wider documented by the recent literature [29], and citations therein. However, at this time, there are no specific regulations in Europe [30].…”

“…Recently Frias and Nash [6] defined microplastics as "any synthetic solid particle or polymeric matrix, with regular or irregular shape and with size ranging from 1 µm to 5 mm, of either primary or secondary manufacturing origin, which are insoluble in water". To date microplastics have been detected in water [7,8], and sediments [9] coming from different environments worldwide: sea surface and water column [10], lakes and rivers [4,11], coastal areas [12], harbours [13], marine protected areas [14], deep oceans [15], polar ecosystems [16], and coral reefs [17].…”

Microplastic Distribution at Different Sediment Depths in an Urban Estuary

“…Benthos is an important feeding environment for many marine species (Anderson and Lovvorn, 2008;MacDonald et al, 2012;Gittman and Keller, 2013) and a recent study has shown marine benthic species ingest microplastics (Courtene-Jones et al, 2017). Knowledge of the harmful effects of microplastics on benthic marine species and communities is growing (Green, 2016;Galloway et al, 2017), however, little is known of past microplastic accumulation in benthic environments.…”