Microplastic ingestion ubiquitous in marine turtles

Despite concerns regarding the environmental impacts of microplastics, knowledge of the incidence and levels of synthetic particles in large marine vertebrates is lacking. Here, we utilize an optimized enzymatic digestion methodology, previously developed for zooplankton, to explore whether synthetic particles could be isolated from marine turtle ingesta. We report the presence of synthetic particles in every turtle subjected to investigation (n = 102) which included individuals from all seven species of marine turtle, sampled from three ocean basins (Atlantic [ATL]: n = 30, four species; Mediterranean (MED): n = 56, two species; Pacific (PAC): n = 16, five species). Most particles (n = 811) were fibres (ATL: 77.1% MED: 85.3% PAC: 64.8%) with blue and black being the dominant colours. In lesser quantities were fragments (ATL: 22.9%: MED: 14.7% PAC: 20.2%) and microbeads (4.8%; PAC only; to our knowledge the first isolation of microbeads from marine megavertebrates). Fourier transform infrared spectroscopy (FT‐IR) of a subsample of particles (n = 169) showed a range of synthetic materials such as elastomers (MED: 61.2%; PAC: 3.4%), thermoplastics (ATL: 36.8%: MED: 20.7% PAC: 27.7%) and synthetic regenerated cellulosic fibres (SRCF; ATL: 63.2%: MED: 5.8% PAC: 68.9%). Synthetic particles being isolated from species occupying different trophic levels suggest the possibility of multiple ingestion pathways. These include exposure from polluted seawater and sediments and/or additional trophic transfer from contaminated prey/forage items. We assess the likelihood that microplastic ingestion presents a significant conservation problem at current levels compared to other anthropogenic threats.

E. M. Duncan, A. C. Broderick, W. J. Fuller and al., Global Change Biology, 04 December 2018

The article

Microplastics contaminate the deepest part of the world’s ocean

Millions of metric tons of plastics are produced annually and transported from land to the oceans. Finding the fate of the plastic debris will help define the impacts of plastic pollution in the ocean. Here, we report the abundances of microplastic in the deepest part of the world’s ocean. We found that microplastic abundances in hadal bottom waters range from 2.06 to 13.51 pieces per litre, several times higher than those in open ocean subsurface water. Moreover, microplastic abundances in hadal sediments of the Mariana Trench vary from 200 to 2200 pieces per litre, distinctly higher than those in most deep sea sediments. These results suggest that manmade plastics have contaminated the most remote and deepest places on the planet. The hadal zone is likely one of the largest sinks for microplastic debris on Earth, with unknown but potentially damaging impacts on this fragile ecosystem.

X. Peng, M. Chen, S. Chen and al., Geochemical Perspectives Letters v9, Published 27 November 2018

The article

Exploration of microplastics from personal care and cosmetic products and its estimated emissions to marine environment: An evidence from Malaysia

This study aims understand microplastics from personal care and cosmetic products in Malaysia via quantification and characterization of microplastics together with emission estimation to marine environment. A total of 214 respondents from all over Malaysia were surveyed with identification of top ten personal care and cosmetic products usage. Particles found in facial cleaner/scrub and toothpaste were colored and colorless with majority of granular shapes. Particles in toothpaste were found between 3 and 145 μm while particles in facial cleaner/scrub were found to be between 10 and 178 μm, stipulating the presence of microplastics. Plastic polymers (LDPE and polypropylene) were found in all facial cleaner/scrub samples while only plastic polymers (LDPE) were present in toothpaste sample G. A total of 0.199 trillion microplastics are expected to be released annually to marine environment in Malaysia. Personal care and cosmetic products are seen as one of the microplastics sources for Malaysia and worldwide.

S. Mangala Praveena, S. N. M. Shaifuddin, S. Akizuki, Marine Pollution Bulletin, Volume 136, November 2018, Pages 135-140

The article

Ecotoxicological effects of polystyrene microbeads in a battery of marine organisms belonging to different trophic levels

The aim of this study was to detect ecotoxicological effects of 0.1 μm polystyrene microbeads in marine organisms belonging to different trophic levels. MP build up, lethal and sub-lethal responses were investigated in the bacterium Vibrio anguillarum (culturability), in the green microalga Dunaliella tertiolecta (growth inhibition), in the rotifer Brachionus plicatilis (mortality and swimming speed alteration) and in the sea urchin Paracentrotus lividus (immobility and swimming speed alteration) exposed to a wide range of microplastic (MP) concentrations (from 0.001 to 10 mg L−1). Survival was not affected in all organisms up to 10 mg L−1, while algal growth inhibition, rotifer and sea urchin larvae swimming behaviour alterations were observed after exposure to MPs. Ingestion was only observed in rotifers and it was directly correlated with sub-lethal effects.

C. Gambardella, S. Morgana, M. Bramini and al., Marine Environmental Research, Volume 141, October 2018, Pages 313-321

The article

Distribution and composition of floating macro litter off the Azores archipelago and Madeira (NE Atlantic) using opportunistic surveys

The distribution and composition of macro litter floating around oceanic islands is poorly known, especially in the North Atlantic. Due to its isolated location at the fringe of the North Atlantic subtropical gyre, the Azores archipelago has recently been proposed as a potential retention zone for floating litter. To further investigate this assumption, opportunistic surveys from pole-and-line tuna fishing boats were performed from 2015 to 2017 to document (1) the distribution and (2) the composition of the floating macro litter present off the Azores and Madeira islands. Among the 2406 visual transects, 482 floating debris were recorded and were mainly composed of general plastic user items (48%), plastic packaging (21%) and derelict fishing gears (18%). Average number of debris per transect was 0.19 ± 0.5, with a total number ranging between 0 and 5 items per transect. For the majority of transects (84%), no debris was observed, 13% of the transects contained a single item, and only 3% contained more than one item. Although debris between 2.5 and 5 cm were recorded, 93% of the debris were larger than 5 cm. The GLMs showed strong effect of the observer (p < 0.001) and the standardized densities accounting for the observer bias were higher (1.39 ± 0.14 items.km-2) than the observed densities (0.78 ± 0.07 items.km−2). Debris densities were however relatively low and tended to aggregate around the Central group of the Azores (standardized mean: 0.90 ± 0.20 items.km−2). Our findings therefore suggest that most of the debris might originate from far away land-based sources and from fishing activities. This study highlights the potential of fisheries observer programs to obtain cost-effective information on floating macro debris that are essential to support the implementation of the European Marine Strategy Framework Directive.

P. Chambault, F. Vandeperre, M. MAchete and al., Marine Environmental Research, Volume 141, October 2018, Pages 225-232

The article

Double trouble in the South Pacific subtropical gyre: Increased plastic ingestion by fish in the oceanic accumulation zone

Fish are an important food source for South Pacific (SP) island countries, yet there is little information on contamination of commercial marine fish species by plastic. The aim of our study was to perform a broad-scale assessment of plastic ingestion by fish common in the diet of SP inhabitants. We examined 932 specimens from 34 commercial fish species across four SP locations, and some of the prey they ingested, for the presence of marine plastics. Plastic was found in 33 species, with an average ingestion rate (IR) of 24.3 ± 1.4% and plastic load of 2.4 ± 0.2 particles per fish. Rapa Nui fish exhibited the greatest IR (50.0%), significantly greater than in other three locations. Rapa Nui is located within the SP subtropical gyre, where the concentration of marine plastics is high and food is limited. Plastic was also found in prey, which confirms the trophic transfer of microplastics.

A. Markic, C. Niemand, J. H. Bridson and al., Marine Pollution Bulletin, Volume 136, November 2018, Pages 547-564

The article

Composition and abundance of benthic marine litter in a coastal area of the central Mediterranean Sea

Abundance and qualitative composition of benthic marine litter were investigated in a coastal area of the central Mediterranean Sea. Almost 30 km of video footage, collected by a Remotely Operated Vehicle between 5 and 30 m depth, were analyzed. Litter density ranged from 0 to 0.64 items/m2 with a mean of 0.11 (±0.16) items/m2. General wastes, made up almost entirely of plastic objects, were the dominant sources of debris representing 68% of the overall litter. The remaining 32% consisted of lost or abandoned fishing gears. Synthetic polymers, considering both fishing gears and general waste, represented 73% of total debris items. Our results are comparable with litter amounts reported in other Mediterranean sites at similar depths. Overall, the results are discussed in terms of monitoring strategy, to support the implementation of the Marine Strategy Framework Directive (2008/56/EC) for descriptor 10 and the Mediterranean UN Environment (UNEP/MAP) regional Plan on Marine Litter.

P. Consoli, M. Falautano, M. Sinopoli and al., Marine Pollution Bulletin, Volume 136, November 2018, Pages 243-247

The article