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Leaching of plastic additives to marine organisms
2014
Koelmans, Albert A. | Besseling, Ellen | Foekema, Edwin M.
It is often assumed that ingestion of microplastics by aquatic species leads to increased exposure to plastic additives. However, experimental data or model based evidence is lacking. Here we assess the potential of leaching of nonylphenol (NP) and bisphenol A (BPA) in the intestinal tracts of Arenicola marina (lugworm) and Gadus morhua (North Sea cod). We use a biodynamic model that allows calculations of the relative contribution of plastic ingestion to total exposure of aquatic species to chemicals residing in the ingested plastic. Uncertainty in the most crucial parameters is accounted for by probabilistic modeling. Our conservative analysis shows that plastic ingestion by the lugworm yields NP and BPA concentrations that stay below the lower ends of global NP and BPA concentration ranges, and therefore are not likely to constitute a relevant exposure pathway. For cod, plastic ingestion appears to be a negligible pathway for exposure to NP and BPA.
Показать больше [+] Меньше [-]Accumulation and toxicity of monoaromatic petroleum hydrocarbons in early life stages of cod and haddock
2019
Sørensen, Lisbet | Hansen, Bjørn Henrik | Farkas, Júlia | Donald, Carey E. | Robson, William J. | Tonkin, Andrew M. | Meier, Sonnich | Rowland, Steven J.
A multitude of recent studies have documented the detrimental effects of crude oil exposure on early life stages of fish, including larvae and embryos. While polycyclic aromatic hydrocarbons (PAHs), particularly alkyl PAHs, are often considered the main cause of observed toxic effects, other crude oil derived organic compounds are usually overlooked. In the current study, comprehensive two-dimensional gas chromatography coupled to mass spectrometry was applied to investigate the body burden of a wide range of petrogenic compounds in Atlantic haddock (Melanogrammus aeglefinus) and cod (Gadus morhua) embryos that had been exposed to sublethal doses of dispersed crude oil. Several groups of alkylated monoaromatic compounds (e.g. alkyl tetralins, indanes and alkyl benzenes), as well as highly alkylated PAHs, were found to accumulate in the fish embryos upon crude oil exposure. To investigate the toxicity of the monoaromatic compounds, two models (1-isopropyl-4-methyltetralin and 1-isopropyl-4-methylindane) were synthesized and shown to bioaccumulate and cause delayed hatching in developing embryos. Minor developmental effects, including craniofacial and jaw deformations and pericardial edemas, were also observed at the highest studied concentrations of the alkylindane.
Показать больше [+] Меньше [-]Allometric relationships to liver tissue concentrations of cyclic volatile methyl siloxanes in Atlantic cod
2014
Warner, Nicholas A. | Nøst, Therese H. | Andrade, Héctor | Christensen, Guttorm
Spatial distribution and relationship of allometric measurements (length, weight and age) to liver concentrations of cyclic volatile methyl siloxanes (cVMS) including octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclosiloxane (D6) in Atlantic cod (Gadus morhua) collected near the community of Tromsø in Northern Norway were assessed. These congeners were benchmarked against known persistent polychlorinated biphenyls (PCBs 153 and 180) to assess accumulation behavior of cVMS. D5 was the dominate cVMS detected in all fish livers with lipid normalized concentrations up to 10 times or greater than those observed for PCB 153 and 180. D4 and D6 concentration were negatively correlated with fish length and weight, indicating a greater elimination capacity compared to uptake processes with increasing fish size for these chemicals. These results indicate relationships between allometric measurements and cVMS concentrations may account for concentration variations observed within fish and should be assessed in future studies evaluating cVMS bioaccumulation potential.
Показать больше [+] Меньше [-]Comparison of the efficiency and modes of capture of biodegradable versus nylon gillnets in the Northeast Atlantic cod (Gadus morhua) fishery
2022
Cerbule, Kristine | Herrmann, Bent | Grimaldo, Eduardo | Larsen, Roger B. | Savina, Esther | Vollstad, Jørgen
Modern gillnets are usually made of nylon with high breaking strength, suitable elasticity and durability making them an efficient fishing gear. Lost, abandoned, or discarded gillnets at sea cause plastic pollution and can continue capturing marine animals over long periods of time. Biodegradable materials are being developed to replace nylon in gillnets. However, biodegradable gillnets have shown reduced catch efficiency compared to the nylon gillnets which challenges their acceptance by the fishing sector. This study investigated catch efficiency and modes of capture between biodegradable and nylon gillnets in commercial cod (Gadus morhua) fishery. On average, new biodegradable gillnets caught 25% fewer cod compared to new nylon gillnets. The main capture modes were by the gills and by the body in used and new biodegradable gillnets, respectively. Differences in catch efficiency are related to specific modes of capture that may be related to differences in material properties.
Показать больше [+] Меньше [-]Occurrence of plastics ingested by Atlantic cod (Gadus morhua) destined for human consumption (Fogo Island, Newfoundland and Labrador)
2020
Saturno, Jacquelyn | Liboiron, Max | Ammendolia, Justine | Healey, Natasha | Earles, Elise | Duman, Nadia | Schoot, Ignace | Morris, Tristen | Favaro, Brett
In the province of Newfoundland and Labrador, fishing is a core occupation and also a source of marine plastic pollution. To look at this relationship, we examined 216 gastrointestinal tracts of Atlantic cod (Gadus morhua) caught by commercial fishers at Fogo Island, Newfoundland and Labrador, Canada. We found three tracts contained plastic for a frequency of occurrence of 1.4%. While this result is consistent with other cod sampled in the province, this study found two gastrointestinal tracts contained intact bait bags, used in commercial pots, and the third tract contained a polypropylene thread, likely originating from fishing rope. Our findings demonstrate the frequency of plastic ingestion in this region is low, but fishing-gear related plastics represent a key source of marine plastics in the region that should be addressed.
Показать больше [+] Меньше [-]The effect of long-term use on the catch efficiency of biodegradable gillnets
2020
Grimaldo, Eduardo | Herrmann, Bent | Jacques, Nadine | Kubowicz, Stephan | Cerbule, Kristine | Su, Biao | Larsen, Roger | Vollstad, Jørgen
The effect of long-term use on the catch efficiency of biodegradable gillnets was investigated during commercial fishing trials and in controlled lab aging tests. The relative catch efficiency between biodegradable and nylon gillnets was evaluated over three consecutive fishing seasons for Atlantic cod (Gadus morhua) in Norway. The biodegradable gillnets progressively lost catch efficiency over time, as they caught 18.4%, 40.2%, and 47.4% fewer fish than the nylon gillnets during the first, second, and third season, respectively. A 1000-hour aging test revealed that both materials began to degrade after just 200 h and that biodegradable gillnets degraded faster than the nylon gillnets. Infrared spectroscopy revealed that the chemical structure of the biodegradable polymer changed more than the nylon. Although less catch efficient than nylon gillnets, biodegradable gillnets have great potential for reducing both capture in lost fishing gear and plastic pollution at sea, which are major problems in fisheries worldwide.
Показать больше [+] Меньше [-]Acetylcholinesterase activity in the host–parasite system of the cod Gadus morhua and acanthocephalan Echinorhynchus gadi from the southern Baltic Sea
2014
Podolska, M. | Nadolna, K. | Szostakowska, B.
Acetylcholinesterase (AChE) activity measurement is widely used as a specific biomarker of neurotoxic effects. The aim of this study was to evaluate AChE activity in a host fish (the cod) and its acanthocephalan parasite Echinorhynchus gadi from the southern Baltic. AChE activity in hosts and parasites was inversely related: the highest cod AChE activity corresponded to the lowest E. gadi enzymatic activity and vice versa (“mirror effect”). This is the first report on the simultaneous application of this biomarker in cod and its acanthocephalan parasites. Results obtained for the host–parasite system are complementary and provide comprehensive information about the response of this biomarker. Analysis of the system allows for detection of a greater number of factors influencing AChE activity in the marine environment than separate analysis of the host and parasites. Thus, AChE activity measurement in a host–parasite system may be considered to be a promising tool for biomonitoring.
Показать больше [+] Меньше [-]A baseline study of levels of mercury, arsenic, cadmium and lead in Northeast Arctic cod (Gadus morhua) from different parts of the Barents Sea
2013
Julshamn, Kaare | Duinker, Arne | Nilsen, Bente M. | Frantzen, Sylvia | Maage, Amund | Valdersnes, Stig | Nedreaas, Kjell
This study is one of several baseline studies that will provide basic and reliable information about the content of undesirable substances in important species of fish caught in Norwegian waters. Concentrations of metals in the muscle and liver of more than 800 Northeast Arctic cod caught at 32 sites in the Barents Sea are reported. The highest concentration of both mercury in the muscle and cadmium in the liver was found in cod caught in the western part of the Barents Sea, while the highest concentration of total arsenic was found in cod from the eastern part. The arsenic concentrations varied greatly among individual fish, ranging from 0.3 to 170mgkg−1 wet weight in the muscle. Such high levels of total arsenic have never previously been reported in any fish, and the primary factor for these high concentrations is likely to be the shrimp in the cod diet.
Показать больше [+] Меньше [-]Effects of depth and overgrowth of ephemeral macroalgae on a remote subtidal NE Atlantic eelgrass (Zostera marina) community
2022
Baden, S. (Susanne) | Fredriksen, Stein | Christie, Hartvig | Eriander, Louise | Gustafsson, Camilla | Holmer, Marianne | Olesen, Birgit | Thormar, Jonas | Boström, Christoffer
We conducted a short-term field sampling complemented with time integrating stable isotope analysis to holistically investigate status and ecological interactions in a remote NE Atlantic Zostera marina meadow. We found high nutrient water concentrations, large biomass of fast-growing, ephemeral macroalgae, low abundance, and biodiversity of epifauna and a food web with thornback ray (Raja clavata) as intermediate and cod (Gadus morhua) as top predator. We observed no variation with increasing depth (3.5–11 m) except for decreasing shoot density and biomass of Zostera and macroalgae. Our results indicate that the Finnøya Zostera ecosystem is eutrophicated. During the past three to four decades, nutrients from aquaculture have steadily increased to reach 75% of anthropogenic input while the coastal top predator cod has decreased by 50%. We conclude that bottom-up regulation is a predominant driver of change since top-down regulation is generally weak in low density and exposed Zostera ecosystems such as Finnøya.
Показать больше [+] Меньше [-]The role of oceanographic processes and sedimentological settings on the deposition of microplastics in marine sediment: Icelandic waters
2021
Loughlin, Christine | Marques Mendes, Ana R. | Morrison, Liam | Morley, Audrey
The global distribution of microplastic debris on the sea floor poses an increasing risk to marine organisms and ecosystems. Here, we present a distribution analysis of microplastics collected from eight marine multicores recovered from the Iceland continental shelf and surrounding areas at water depth between 241 and 1628 m. We report a total of 306 microplastics from the size range > 250 μm −5 mm, of which all were fibers. Microplastic numbers range between 0.119 and 0.768 per gram of dry sediments. In the analysis we assess the potential role of oceanic surface and bottom water currents, organic content, and sediment type on the distribution, deposition, and burial of microplastics in marine sediments. Our results provide the first record of microplastic pollution of marine sediments from the Iceland continental shelf and identify Atlantic Cod feeding and breeding grounds as potential hot spot for the accumulation of marine debris.
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