5 Gygres
Written by Sandra Marshall
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03 June 2010
Look around. Most of what we eat, drink, or use in any way comes packaged in petroleum plastic, a material designed to last forever. The short-term convenience of using and throwing away plastic products i.e. water bottles, cups, utensils, shopping bags, food to go boxes, electronics, toys, and gadgets, has presented a very inconvenient long-term truth. Plastic is becoming a growing plague, clogging waterways, damaging marine ecosystems, and entering the marine food web becoming a hazard for marine wildlife, and ultimately for us.
Currently only 5% of the plastics produced is recovered. Roughly 50% is buried in landfills, some is remade into durable goods, and much of it remains “unaccounted for”, lost in the environment where it ultimately washes out to sea through storm drains and watersheds
In the ocean, some of these plastics, Polycarbonate, Polystrene, and PETE, sink, while LDPE, HDPE, Polypropylene, and foamed plastics float on the oceans surface. Sunlight and wave action cause these floating plastics to fragment, breaking into increasingly smaller particles, but never completely disappearing, at least on any documented time scale.
Our oceans are dynamic systems, made up of complex networks of currents that circulate water around the world. These large systems of currents coupled with wind and the earth’s rotation, create “gyres”, massive, slow rotating whirlpools in which plastic trash can accumulate.
There are 5 major oceanic gyres worldwide, with several smaller gyres in Alaska and Antarctica. Plastic debris is accumulating in each of the 5 oceanic gyres. The North Pacific Gyre, the most heavily researched for plastic pollution, spans an area roughly twice the size of the United States - though it is a fluid system, shifting seasonally in size and shape. Because petroleum plastics are designed to last, plastic trash in the gyre will remain for decades or longer, being pushed gently in a slow, clockwise spiral towards the center. Marine researchers don’t yet know the extent to which plastic pollution exists in the world’s oceans.
As plastic particles circulate through oceans, they act as sponges for waterborne contaminants such as PCBs, DDT and other pesticides, PAHs and many hydrocarbons washed through our watersheds. These persistent organic pollutants, called “POPs”, absorb and adsorb onto plastic pollution in high concentrations. Plastic pollution is not a benign material in the ocean. Scientists are studying whether these POPs transfer to the marine organisms that mistakenly consume them.
Fish aren’t supposed to eat plastic, however, 44% of all seabird species, 22% of...Cetaceans, all sea turtle species, and a growing list of fish species have been documented with plastic in or around their bodies. When marine animals consume plastic trash, presumably mistaking it for food, this can lead to internal blockages, dehydration, starvation, and potentially death.
Science is beginning to ask the hard questions: Do chemicals such as PCBs and DDTs, that sorb onto plastic pellets, get into the tissues and blood of the animals that eat plastic? Do these chemicals work their way up the food chain, becoming increasingly concentrated and potentially entering our bodies when we eat seafood?
Additional sources: Algalita Marine Research Foundation - algalita.org highlighted the “Pacific Garbage Patch”, an area of plastic accumulation in the North Pacific between California and Hawaii.
Studies by the Sea Education Association, (SEA), in the Atlantic have documented plastic pollution in the North Atlantic Gyre.