Research suggests that plastic debris has been present in the marine environment for at least 60 years (Avio et al. 2017). However, due to the recent increase in media coverage from documentaries, such as Blue Planet II, public interest in marine contaminants has intensified. It is now recognised that plastics are the most abundant form of marine litter, accounting towards 60-80% of all marine debris (Foekema et al. 2013). One of the predominant issues with the presence of plastic in the marine environment is from consumption by organisms and subsequent entry into the food web. Consumption of plastics can result in a variety of health issues in marine species, including problems with digestion and feeding (Fendall & Sewell, 2009; Rummel et al. 2016). As in the marine environment, it is possible for humans to ingest microplastics from seafood. The issue with the presence of plastics in marine fisheries to human health has been raised in research with some evidence indicating that plastics absorb toxins that are carcinogenic (Mozaffarian & Rimm, 2006; Seltenrich, 2015). However, the exact health risks are currently unclear and previous studies have highly recommended that further research is needed to determine the exact health issues that may arise from human ingestion of plastic (Seltenrich, 2015).
With reference to the North Western district, little site-specific research has been conducted on the presence of plastics in commercially important species. One recent study by Li et al. (2018) found that plastic is accumulating in UK mussels, which are filter feeders, with one of the sample sites at Wallasey in the north west demonstrating plastic’s presence in mussels. However, in a BBC (2018) interview the authors of the paper stated that the concentration of microplastic found in the sampled mussels is less than the amount that is found in the air that we breathe. Similar studies have not been conducted for other commercially important molluscs, such as cockles and whelks and it is, therefore, unclear as to whether they would demonstrate a similar concentration to the tested mussels. In terms of commercially valuable crustaceans, research has demonstrated that species are capable of ingesting monofilaments and portions of plastic bags. Further evidence was shown when Nephrops norvegicus collected in the Clyde Sea, Scotland, contained microplastics (Murray & Cowie, 2011) but it is unclear whether these results would be mirrored in the Irish Sea. There are uncertainties with regards to plastic content in other commercially valuable crustacean species, including the European lobster and edible crab. Studies in locations including the North Sea have shown that commercially valuable finfish species, such as cod, do contain plastic debris (Foekema et al. 2013). Yet once again, there is no published research for the Irish Sea with regards to plastic content and it is currently unclear whether all finfish species are vulnerable to plastic consumption.
It is clear from the current information that further site-specific research is required to fully understand the status of plastic contamination in the fisheries of the North Western IFCA district. However, plastics pose major threats towards the health of fisheries and the natural environment as a whole. Therefore, every effort should be made to attempt to reduce and mitigate the current levels of plastic that are entering the marine environment.
The BBC interview is available here:
https://www.bbc.co.uk/news/av/uk-44416717/plastic-and-cotton-found-in-uk-s-wild-mussels
Literature Cited:
Avio, C.G., Gorbi, S., & Regoli, F. 2017. Plastics and microplastics in the oceans: From emerging pollutants to emerged threat. Marine Environmental Research, 128, pp. 2-11.
BBC. 2018. Plastic and cotton found in UK’s wild mussels. Online. Available at: https://www.bbc.co.uk/news/av/uk-44416717/plastic-and-cotton-found-in-uk-s-wild-mussels. Accessed: 13/06/18.
Fendall, L.S., & Sewell, M.A. 2009. Contributing to marine pollution by washing your face: Microplastics in facial cleaners. Marine Pollution Bulletin, 58, pp. 1225-1228.
Foekema, E.M., Gruijter, C.D., Mergia, M.T., Franeker, J.A., Murk, A.T.J., & Koelmans, A.A. 2013. Plastic in North Sea fish. Environmental Science & Technology, 47(15), pp. 8818-8824.
Mozaffarian, D., & Rimm, E.B. 2006. Fish intake, contaminants, and human health. Evaluating the risks and the benefits. Clinical Review, 296(15), pp. 1885-1899.
Murray, F., & Cowie, P.R. 2011. Plastic contamination in the decapod crustacean Nephrops norvegicus (Linnaeus, 1758). Marine Pollution Bulletin, 62(6), pp. 1207-1217.
Seltenrich, N. 2015. New link in the food chain? Marine plastic pollution and seafood safety. Environmental Health Perspective, 123(2), p. A34.
Rummel, C.D., Löder, M.G.J., Fricke, N.F., Lang, T., Griebeler, E.M., Janke, M., & Gerdts, G. 2016. Plastic ingestion by pelagic and demersal fish from the North Sea and Baltic Sea. Marine Pollution Bulletin, 102, pp. 134-141.