Monday, 2 January 2012

Plastic Pollution in the World’s Oceans

 

The Great Pacific Garbage Patch, also described as the Pacific Trash Vortex, is a gyre of marine litter in the central North Pacific Ocean located roughly between 135°W to 155°W and 35°N to 42°N. The patch extends over an indeterminate area, with estimates ranging very widely depending on the degree of plastic concentration used to define the affected area.

Let’s start off with a definition-

Marine Debris: Solid materials, typically waste, that has found its way to the marine environment. It is known to be the cause of injuries and deaths of numerous marine animals and birds, either because they become entangled in it or they mistake it for prey and eat it.

Take a look around you; most of what we eat, drink, or use in any way comes packaged in petroleum plastic, a material designed to last forever, yet used for products that we then throw away. This throwaway mentality is a relatively recent phenomenon. Just a generation ago, we packaged our products in reusable or recyclable materials – glass, metals, and paper, and designed products that would last. Today, our landfills and beaches are awash in plastic packaging, and expendable products that have no value at the end of their short lifecycle.

At least 267 different species are known to have suffered from entanglement or ingestion of marine debris including seabirds,turtles, seals, sea lions, whales and fish. The scale of contamination of the marine environment by plastic debris is vast. It is found floating in all the world’s oceans, everywhere from polar regions to the equator.

Of the over 31 billion bottles of water sold a year, only about 10% are recycled. That means that 27.9 billion plastic bottles end up in landfills and oceans every year.

It is the very properties that make plastics so useful, their stability and resistance to degradation, that causes them to be so problematic after they have served their purpose.These materials persist in the environment and are not readily degraded or processed by natural biological mechanisms. However plastics in the ocean are weathered; broken up either mechanically or by the action of sunlight into smaller and smaller fragments. Eventually, fragments are reduced to into tiny pieces the size of grains of sand.These particles have been found suspended in seawater and on the seabed in sediments. Even such tiny particles may be causing harm to the marine environment since they have been shown to be ingested by small sea creatures and may concentrate persistent organic pollutants (POPs) present in the seas.

Though ocean-borne plastic trash has a reputation as an indestructible, immortal environmental villain, scientists announced yesterday that some plastics actually decompose rapidly in the ocean. And, the researchers say, that's not a good thing. The team's new study is the first to show that degrading plastics are leaching potentially toxic chemicals such as bisphenol A into the seas, possibly threatening ocean animals, and us. Scientists had previously thought plastics broke down only at very high temperatures and over hundreds of years. The researchers behind a new study, however, found that plastic breaks down at cooler temperatures than expected, and within a year of the trash hitting the water. All the water samples from the study taken all over the world were found to contain derivatives of polystyrene, a common plastic used in disposable cutlery, Styrofoam, and DVD cases, among other things, said Saido, who presented the findings at a meeting of the American Chemical Society in Washington, D.C., today. Plastic, he said, should be considered a new source of chemical pollution in the ocean. The toxic compounds the team found don't occur naturally in the ocean, and the researchers thought plastic was the culprit. The scientists later simulated the decomposition of polystyrene in the sea and found that it degraded at temperatures of 86 degrees Fahrenheit (30 degrees Celsius). Left behind in the water were the same compounds detected in the ocean samples, such as styrene trimer, a polystyrene by-product, and bisphenol A, a chemical used in hard plastics such as reusable water bottles and the linings of aluminum cans. Bisphenol A (BPA) has been shown to interfere with the reproductive systems of animals, while styrene monomer is a suspected carcinogen.The pollutants are likely to be more concentrated in areas heavily littered with plastic debris, such as ocean vortices, which occur where currents meet.

Ocean micro-plastic: These samples were collected from the surface water of the North Pacific Ocean by the SUPER expedition in 2008.

About 44 percent of all seabirds eat plastic, apparently by mistake, sometimes with fatal effects. And 267 marine species are affected by plastic garbage—animals are known to swallow plastic bags, which resemble jellyfish in mid-ocean, for example—according to a 2008 study in the journal Environmental Research by oceanographer and chemist Charles Moore, of the Algalita Marine Research Foundation.Now, it seems, they also face the invisible threat of toxic, plastic-derived chemicals.Once Styrofoam, for example, breaks down, the tiny polystyrene components start to sink, because they're heavier than water, Moore said. "So it's likely that this styrene pollutant is prevalent throughout the water column and not just at the surface." Plastic hits marine creatures with a double whammy, Moore said. Along with the toxic chemicals released from the breakdown of plastic, animals also take in other chemicals that the plastic has accumulated from outside sources in the water. "We knew ten years ago that plastic could be a million times more toxic than the seawater itself," because plastic items tend to accumulate a surface layer of chemicals from seawater, Moore said. "They're sponges."Moore worries about the plastic-derived chemicals' potential damage to wildlife. The chemicals can potentially cause cancer in humans, he said, and simpler life-forms "may be more susceptible then we are."Pollutants also become more concentrated as animals eat other contaminated animals—which could be bad news for us, the animals at the top of the food chain.

Although this only touches on the surface of what plastic pollution does to the marine environment please bear it in mind next time you go to throw your plastic bottle in the trash or choose to buy products with non recyclable plastic packaging. Please Recycle and do your part to educate others on this issue.

 

“The Garbage Patch”: Plastics in our oceans

2 comments:

  1. Think this particular blog is interesting and gives people real food for thought. If people could manage with paper, glass and such packaging in previous years..why has it developed now that we use more and more plastic? They had much bigger families than us, surely they needed better packaging and packaging that preserves food for longer...but they managed! and with particular reference to polystirene?? (cannot spell that to save me life, its a waste...it really is...it doesnt even do anything...useless peice of packaging...half of peoples christmas presents this year probably came wrapped in that...for what...its has no other purpose but to fill a box...

    Anyway just thought id say brill article...good read...and gives our fantastic brains something to think about...if i was a marine animal...i wouldnt fancy chewing on a piece of plastic..yuk!

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  2. Thank you for the comment :) well in the past they didn't have the plastic that we have now, it is primarily used en masse today because it is cheap, lightweight and preserves food/contents more efficiently. The real problem is the use of non recyclable plastics and those who do not recycle their plastic that can be recycled(it should be made law to do so).

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