Plastic is a huge part of everyday life. It is used in or to package most household items. But have you ever thought about what happens to your plastic once you’ve finished with it? It is a sad truth that a lot of plastic isn’t properly disposed of. Even when it is disposed of correctly is often blown or washed into rivers and lakes. Plastic is now incredibly common in the sea and can be found worldwide. It is so common, in fact, that five islands of plastic have developed which have been named gyres.
You have no doubt heard about turtles, birds and mammals choking on large plastic items. Well known examples include dolphins being caught in abandoned or lost fishing nets, turtles mistaking carrier bags for jellyfish and birds with their necks caught in six pack rings. Even if you were not aware of the impacts of plastics, we have all seen its abundance on shorelines and riverbanks. Perhaps more astonishing is the sheer abundance of what we cannot see.
Microplastics are tiny fragments of plastic that accumulate in the ocean and are present in incredible quantities. Some microplastics are made to be this small: microbeads in face scrubs or nurdles (plastic pellets used to make most other plastics). Others are fragments of larger plastics. The most common plastics in the ocean are fibres. These could originate from several sources, but the most likely are the fishing industry and water treatment facilities. Did you know that nearly 2000 fibres shed from a fleece every time you wash it (Browne et al., 2011)? Filters in washing machines and sewage treatment plants are not able to filter out most of these fibres and thus thousands enter the sea with every wash.
Researcher Alex McGoran, Royal Holloway University of London, has been studying the issue for two years. Her research aims to compare microplastic ingestion in fish between the Thames and the Clyde Sea. For the past month Alex has been sampling fish from the Clyde from FSC’s Millport centre. In total over 600 animals will be analysed. Previous work by Alex at Royal Holloway has shown that up to 75% of some fish species could have ingested plastic. The effects that this plastic has is unknown at present. It is, however, known that plastics in the sea absorb persistent organic pollutants, such as PCB, and can leach chemicals used in plastic production. These chemicals can be cancer-causing and affect the reproduction and fitness of fish.
How do we stop plastic pollution? Much of what is in the ocean is from historic sources; plastics have been used for decades and have long been improperly disposed of and lost. Microplastics are difficult to remove and travel through the food chain staying in the system. Recycling, proper disposal and taking responsibility for our waste are key to solving this issue.
Mark Anthony Browne, Phillip Crump, Stewart J. Niven, Emma Teuten, Andrew Tonkin, Tamara Galloway, Richard Thompson (2011). Accumulation of Microplastic on Shorelines Worldwide: Sources and Sinks. Environmental Pollution 45, 9175 – 9179