Plastics in the Ocean - Interactions with biota
- 09:00 Plastics and microplastics in Atlantic cod (Gadus morhua) and mussels (Mytilus spp.) from the Norwegian environment.
Authors: Inger Lise N. Bråte ( NIVA ); Amy Lusher ( NIVA ); Rachel Hurley ( NIVA ); David Eidsvoll ( NIVA ); Calin Steindal ( UiO ); Karine Iversen ( NMBU/NIVA ); Jonny Beyer ( NIVA ); Norman W. Green ( NIVA ); Marianne Olsen ( NIVA ); Kevin V. Thomas ( The University of Queensland/NIVA )
Prior to 2016, no scientific data were available on plastics and microplastics in fish and mussels from the Norwegian environment. Here, the results obtained from two field studies conducted along the Norwegian coast on plastic and microplastic occurrence in the stomachs of Atlantic cod (Gadus morhua, n=303) and whole mussels (Mytilus spp., n=332), are presented (Bråte et al. 2016; Bråte et al. 2018). From current work, it is evident that biota from the Norwegian environment, similarly to biota worldwide, are exposed to and interact with a variety of marine plastics and microplastics in terms of size, shape and polymeric composition. When combining the data for Atlantic cod and mussels, a total of 14 different polymer were identified. Six different polymers were found in both species being polyester (such as PET), polypropylene (PP), polyethylene (PE), polyamide (PA), polyvinyl chloride (PVC) and styrene acrylonitrile resin (SAN), suggesting that Norwegian marine biota are frequently exposed to these polymers. In cod, the few microplastics found were two fibres and a pellet, but there was a larger variety of meso- and macroplastics: fibres were dominant, followed by strips, fragments, foams and tape. In mussels, only microplastics were detected and they ranged in size from 70 µm to 3800 µm, with an average of 770 µm. In total, fibres were the dominant morphotype found in mussels followed by fragments, accounting for 83% and 12%, respectively. Inter-site variability was, however, observed. From the data obtained in this study it is clear that Norwegian fish and mussels are exposed to a multitude of different sources of plastics and microplastics.
Even though, the polymeric composition, size and shape of identified particles can give an indication of their sources, it is still very challenging to make a clear link to the plastic pollution sources. Furthermore, with the methods presented it is likely that some particles were uncharacterised due to detection limits (in fish plastics <200 µm and in mussels plastics <70 µm). Ultimately, it is not understood whether the plastics found in Norwegian cod and mussels are affecting wild cod or mussel which are already exposed to a multitude of environmental stressors. We therefore call for further
- 09:15 Citizen scientists reveal: marine litter pollutes Arctic beaches and affects wild life
Authors: Melanie Bergmann ( Alfred-Wegener-Institut Helmholtz Zentrum für Polar- und Meeresforschung ); Birgit Lutz ( Alfred-Wegener-Institut Helmholtz Zentrum für Polar- und Meeresforschung ); Lars Gutow ( Alfred-Wegener-Institut Helmholtz Zentrum für Polar- und Meeresforschung ); Mine Tekman ( Alfred-Wegener-Institut Helmholtz Zentrum für Polar- und Meeresforschung )
Recent data indicate accumulation areas of marine litter in Arctic waters and significant increases on the seafloor over time. Beaches on remote Arctic islands may be sinks for marine litter and reflect pollution levels of the surrounding waters particularly well. We provide the first quantitative data from surveys carried out by citizen scientists, which participated in sailing cruises around Svalbard in 2016. Litter quantities on six beaches varied from 9 - 524 g m-2 and were similar to those from densely populated areas. Plastics accounted for > 80% of the overall litter, most of which originated from fisheries. Photographs provided by citizens show deleterious effects of beach litter on Arctic wildlife including polar bears (Ursus maritimus), which is already under strong pressure from global climate change. Our study highlights the potential of citizen scientists to provide scientifically valuable data on the pollution of sensitive remote ecosystems. Similar programmes could be adopted in other poorly sampled areas of the world to increase our knowledge base and to stimulate a sense of connectedness with the environment visited.
- 09:30 Microplastic properties and environmental conditions influence PAH sorption and bioavailability to copepods
Authors: Lisbet Sørensen ( SINTEF Ocean ); Emilie Rogers ( NTNU ); Dag Altin ( BioTrix ); Rudolf Schmid ( NTNU ); Iurgi Salaverria ( NTNU ); Andy Booth ( SINTEF Ocean )
Many marine species ingest microplastic (MP), exhibiting extended periods of MP gut retention in some cases. Organic pollutants associated with MP may present an alternative exposure route for these chemicals to marine species. However, the effect of PAH sorption to MP on PAH bioavailability remains poorly understood. Here, we investigate the sorption kinetics for two PAHs (fluoranthene and phenanthrene) to MP in natural seawater under semi-polar (10°C) and temperate (20°C) conditions. Spherical polyethylene (PE) microbeads with mean diameters ranging from 10-200 µm (PE-10, PE-50, PE-100 and PE-200) and polystyrene (PS) microbeads of 10 µm (PS-10) were used. Linear, Freundlich, Langmuir, Dual Langmuir, Redlich-Peterson and Dubinin-Ashtakhov adsorption isotherms were fitted to the data and the best fit identified depending on the MP type, size and temperature combination. For polymer mass and particle surface area, PAH sorption increased in the order PE-10>PS-10>PE-100. For PS-10 and PE-10 at 10 °C, the Redlich-Peterson isotherm model best described the sorption, indicating a combination of monolayer and multilayer adsorption. For PE-10 at 20 °C, the Dubinin-Ashtakhov model fitted best, indicating higher temperatures facilitate PAH transitioning into micropores. For PE-100, linear isotherms fitted best. These results indicate that adsorption processes dominate for smaller MPs (PE-10 and PS-10), while absorption into the polymer matrix becomes significant for larger particles (PE-100).
Using a novel approach, the modular effect of PAH sorption to ingestible and non-ingestible PE MP on PAH lethality and accumulation was investigated using two marine copepod species (Acartia tonsa and Calanus finmarchicus). C. finmarchicus is lipid-rich and represents a model for Arctic copepod species, while A. tonsa is lipid poor and represents a temperate species. A pre-study was performed to determine the ingestible and non-ingestible MP particle sizes for both A. tonsa and C. finmarchicus. The final studies employed 100 µm PE particles to represent non-ingestible MP (both species) and 10 µm particles (mean size) as potentially ingestible for both species. The freely dissolved fraction of PAHs (Cfree) was measured before and after exposure, and the chemical body burden (C. finmarchicus) and observed lethality (both species) were used to determine PAH bioavailability. The difference in Cfree reduction was not reflected in a reduction of lethality and body burden, indicating a negligible amount of MP-sorbed PAH is bioavailable from both ingestible and non-ingestible MP.
- 09:45 Microplastic ingestion in sexual maturing Atlantic cod (Gadus morhua)
Authors: André S Bogevik ( Nofima AS, Bergen ); Katrin Vorkamp ( Aarhus University ); Erik Burgerhout ( Nofima AS, Tromsø ); Helge Tveiten ( Nofima AS, Tromsø ); Velmurugu Puvanendra ( Nofima AS, Tromsø )
Plastic pollution is an increasing problem in the world’s oceans. Microplastic is defined as particles of plastic less than 5 mm, and could originate from components intentionally manufactured at microscopic size or from plastic debris degraded in the ocean. These particles are ingested either by non-selective filter feeders at lower trophic level, at higher trophic levels through passive feeding or mistaken feeding of microplastics as natural prey or feeding of microplastic contaminated prey.
In the PlastiCod project, sexual maturing farmed Atlantic cod (Gadus morhua) were fed two diets, one with the inclusion of 1% microplastic particles and the other without microplastics. The microplastic particles had been placed in the sea (Oslofjord) for 4 months prior the experiment, to obtain realistic conditions, including the potential sorption of organic contaminants. In general, higher concentrations of persistent organic pollutants (POPs) were found in the fish feed than in the microplastic particles. The diets were fed to male and female cod in duplicate tanks from early maturation until spawning at Nofima’s Center for Marine Aquaculture in Tromsø, Norway. Biometric data and samples were obtained at the start of the experiment and at three consecutive time points prior to spawning in spring 2018. Whole fish samples of males and females were analyzed for POPs at each time point. Spawning data was collected throughout the spawning season from both groups. From selected spawners of each dietary group eggs were stripped, incubated and the performance of larvae to day 60 post hatch was observed. No major differences were observed in spawning performance, and adult and larval morphometric data between different groups. Preliminary data analysis does not suggest differences in POP levels between the fish groups either. Further, the differential effects of MP in maturing Atlantic cod and their offspring on nutritional, endocrine and gene expression levels are studied. Selected results will be presented at the conference.
- 10:00 Effects of micro- and nanoplastics on physiology of biota: A review
Authors: Tanja Kögel ( Institute of Marine Research ); Michael S. Bank ( Institute of Marine Research ); Marte Håve ( UniResearch - NORCE ); Ørjan Bjorøy ( Institute of Marine Research ); Marc Berntssen ( Institute of Marine Research ); Monica Sanden ( Institute of Marine Research )
Recent marine plastic investigations have reported the role and importance of smaller particles in biological exposures. Specifically, researchers have shown that smaller particles are more numerous and may be more bioavailable compared to larger particles. Small-scale plastic particles have also been observed in marine fish fillet tissue and larger particles have been found in the liver and the feet of mussels, demonstrating that the intestinal tracts are not the only organ where plastic particles can be found.
Effects of micro- and nanoplastics have been investigated in several organisms inhabiting heterogeneous environments. Here we present a literature review of the effects of micro- and nanoplastics on organism physiology across a taxonomic gradient, under different laboratory conditions and across aquatic habitats. The objective of this study is to provide an overview of the literature and to identify knowledge gaps to develop guidelines for plastic contamination surveillance in support of seafood safety and human health risk assessment.
A synthesis of the literature showed that toxicity of plastics was highly variable and increased with decreasing particle size, longer exposure times and higher doses. Polymer types, weathering, species type and developmental stages of biota were also important parameters influencing plastic toxicity.
Furthermore, a review of the literature has shown the potential of plastic pollution at micro- and nanoscales to reduce feeding activity, energy reserves and nutritional status, and to prolog gut residence times. Growth, reproduction, survival, inflammatory status and predator avoidance mechanisms may also be affected by plastic particle exposure. These direct and indirect effects likely occur at cellular, individual and population levels. First mechanistic insight points towards interactions with lipid transport and metabolism dynamics.
Although we identify potential effects of plastic pollution for different size fractions, plastic toxicity and relative doses at which effects may occur still remain poorly understood or unknown. Comparison of quantitative evidence of plastic particles in different matrices is hampered by overall reliability, different sampling, extraction and measurement methods, and by reporting in different categories, both according to shape, polymer type, particles size and units applied (e.g. mass versus particle numbers). Future research should focus on harmonizing laboratory studies on physiological effects utilizing environmental realistic exposure regimes for toxicity testing.
- 10:15 What did our dinner have for lunch?: Analysing plastics by dissolving fish guts from Atlantic cod
Gadus morhua and saithe Pollachius virens from the west coast of Iceland.
Authors: Adriana Neeltje de Vries ( University Centre of the Westfjords ); Pernilla Carlsson ( NIVA and University Centre of the Westfjords )
In the 1950s, plastic became a revolutionary new material due to its durability, flexibility, low costs, lightweight and corrosive resistance. Unfortunately, plastics end up in the marine environment making up between 60-80% of the marine litter. This pollution may cause economic losses in for example tourism and municipality management. Additionally, organisms that encounter plastic debris may become entangled or ingest particles, often leading to reduced fitness and mobility. Norwegian and Canadian studies has shown the presence of microplastics in fish guts with an occurrence rate around 3%. Although the fishing industry has been, and still is, an important economic factor in Iceland, research related to debris in the marine food web around Iceland is very limited with no research performed on microplastics in fish. This study investigated the occurrence of microplastics in Icelandic cod (Gadus morhua) and saithe (Pollachius virens) from the west coast of Iceland. The biological tissue was digested using a 10% potassium hydroxide (KOH) solution at a ratio of 1:6 w/w with an incubation period of 24 hours at 60°C. This was followed by an addition of citric acid to neutralise the KOH followed by a settlement period of another 24 hours at room temperature. The solution was then filtered before visual analysis by a stereomicroscope. A total of 86 samples (39 cods and 47 saithes) were analysed. Observed plastics were placed in categories (film, filament, foam, fragment or fibre), measured in the longest diameter, and described by colour and shapes. Results from the visual analysis will be confirmed by n-IR. In addition to the digestion method, an additional 34 cod and 39 saithe were dissected manually and the gut content sieved using plentiful water. Further results will be presented at Arctic Frontiers. The present study kept a high focus on quality assurance known to be an analytical issue, especially when the work is carried out in smaller laboratories with little resources. The process here shows that also smaller laboratories can be able to analyse at least certain types of microplastics, which is very useful for evaluation and quantification of microplastics in biota.
Thursday 24th January 2019
09:00 - 10:30