More plastic in the sea than fish by 2050 if action is not taken

In 1997, Charles Moore, an oceanographer and racing boat captain competed in a yacht race and made a disturbing discovery.

Sailing from Hawaii to California, he and his crew expected peaceful, blue horizons and ubiquitous serene views of clear waters. Instead, they came across miles and miles of a thick and cloudy, “soup” like mixture of water, debris and microplastic particles.

It may be invisible from satellite views, but this “Great Pacific Garbage Patch” is real, and it’s not the only one either. Estimated by scientists to range from 250,000 square miles (which is just a bit smaller than Texas), to 6 million square miles, the Great Pacific Garbage Patch contains both large, whole items such as abandoned fishing nets, shoes, plastic bottles, as well as millions of particles of plastic. In a single square kilometer of the patch, around 750,000 bits of plastic were collected.

In the Atlantic Ocean a similar amount of 200,000 pieces per square mile was collected by 7,000 undergraduate students and researchers led by the Sea Education Association (SEA). Their 22 year-long study found that over 60% of the 6136 plankton examined contained plastic. 

It is estimated that there are at least 5 of these great garbage patches, our nearest being in the North Atlantic Ocean. These collections of marine debris are caused by gyres- systems of circular ocean currents which are formed by the earths wind patterns, and there are 5 major gyres found in our oceans. The currents circular motions draw debris into the center of the gyres, where there is a calm and stable zone.

The debris accumulates to such a vast quantity because most of it is not biodegradable, that is, it cannot be fully broken down. The debris is broken down by the sun, through the process of photo degeneration, into tiny microplastic particles. 30% of this debris floats on the surface with other larger items, and the remaining 70% sinks to the ocean floor. The “Garbage Patches” are therefore not always visible with the naked eye, but there are still islands found up to 15m in length of whole pieces of debris, and although it may look better with less whole pieces of floating rubbish, the billions of microplastic particles are much worse for the environment, and according to research, it is almost impossible to clean up.

Microplastics’ oil based composition attracts toxic chemicals in the water, such as DDT and other pesticides and insecticides. Due to photo degeneration, the plastic particles are small enough to be consumed by aquatic organisms, they therefor enter the food chain leading to both the toxic chemicals and microplastics becoming present in many fish and marine mammals.

A recent study found that 1 in 3 fish off British coasts contain microplastic. Alice Horton, a graduate in BSc Biology from Sussex University, recently found that large microplastic particles are present in UK freshwater systems too. During her research, which was published in 2016, 4 sites from the River Thames were examined, and microplastics were found and extracted from all four sites.  In her research, she also identified that road marking paints are another source of microplastics.

It is now apparent that plastic is everywhere; forming huge rubbish islands in all our oceans, and even present in UK freshwater systems and the fish and sea-food that we consume. 80% of the plastic and debris found in the Great Pacific Garbage patch originates from land-based activities in Asia and in North America, and the remaining 20% originates from boats, such as cargo ships that lose or purposefully dump debris, or fishermen that abandon their cheap, replaceable fishing nets. Seals, turtles, dolphins and other marine mammals often get caught up in this debris: entangled in fishing nets, caught in plastic beer can holders, trapped in plastic bags. The microplastic also prevents sunlight from reaching plankton and algae; important autotrophs that are necessary for a healthy food web. The sunlight is needed by them to survive as well as produce important nutrients such as oxygen and carbon, and if they are threatened, then so is the entire food web.

Politicians and world leaders are starting to acknowledge the disturbing amount of plastic found in our waters, (now estimated to be 5 trillion pieces and counting) and its accompanied health concerns. The UK responded by introducing the 5p bag scheme, and are now considering a plastic bottle deposit scheme, where plastic bottles are recycled in return for small amounts of money. This scheme is present in Denmark, where 90% of plastic bottles are recycled, compared to only 58% in Britain.

The “garbage patches” found in our oceans are growing day by day, and scientists believe that the best way to clean up the patches or prevent them from expanding is by eliminating the use of disposable and single use plastic, as most of the microplastic originates from plastic bags, bottle caps, water bottles and Styrofoam. Although clearing up these “garbage patches”, as well as filtering the plastic out of the oceans, would bring great impacts to our environment, this is not feasible as it is very difficult to filter out the plastic without harming small aquatic mammals.

The cost of such a huge procedure is also one that not one country alone wants responsibility for. Despite this, there’s no hiding from the fact that plastic is now found in many fish and even farm mammals, and Dame Ellen MacArthur (a record breaking sailor), warns that there could be more plastic in the sea thanfish by 2050 if nothing is done about this frightening matter. 

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Rosalind Henderson

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