Many of you have probably heard of the Great Pacific Garbage Patch, an area in the mid-Pacific where the clockwise circulation of currents slowly works discarded plastics into a central area (about twice the size of Texas!). You may have visualized it as a floating garbage dump of plastic bags and discarded water bottles that we could, in some herculean effort, scoop all up.
Unfortunately, it's not that simple.
While there certainly are large pieces of plastic that make their way into the Garbage Patch - drawn in by the North Pacific Gyre (the famed "doldrums") and this material can pose a threat to ocean mammals and other animals like sea turtles that will sometimes mistake it for food, what constitutes a large portion of the garbage patch is "microplastic." These are minute pieces of plastic, the end result of being battered and ground by the action of the sea. It makes for a polluted soup that is ingested by a wide range of sea creatures, often unintentionally.
From seabirds all the way to larval fish, microplastic enters the marine food chain and as it does, it releases a variety of polluting chemicals as part of the process of breaking down - this breakdown we have come to call "biodegradable" but plastic doesn't really ever disappear; it simply continues to separate into smaller and smaller components, releasing chemicals into the water and into the tissues of many ocean species, many of which end up on our dinner table.
And this environmental threat is not being confined or contained within the Great Pacific Garbage Patch. After all, the plastic that is there did not just drop out of the sky. It came from the coastlines and spent weeks, months, and maybe even years, floating about, slowly disintegrating and discharging pollutants throughout the ocean, on its way to the ultimate plastic graveyard.
What to do? Well, the obvious answer would be to use less plastic and to dispose of plastic in a manner that keeps it out of the ocean. Both are challenging because the ubiquitous material has become a mainstay of our lives for the past century. And our sewage/trash transport infrastructure is still predominantly designed around the idea that the ocean is our convenient dumping ground. But, we must do what we can to minimize our "polyethylene footprint." (Are you bringing your own cloth bags to the supermarket or at least asking for paper bags over plastic? That's a start.)
Scientists are looking into methods of treating plastic, breaking it down into its base components and producing hydrocarbons - an alternative fuel source. But, currently, it requires more energy than the process produces - much like the problems with the production of ethanol, and the logistics of turning this technology towards such vast areas as the Great Pacific Garbage Patch and others worldwide is truly enormous.
To get a handle on the scope of this problem, read An Ocean of Plastic by Kitt Doucette in the latest print issue (No. 1090) of Rolling Stone (yes, Rolling Stone). I could cite several studies and technical papers, but this article puts the issue into language that everyone can understand. Right now, it's not a pretty picture and we can only hope that our actions to curtail discarded plastic combined with a future breakthrough in technology can stem the tide.
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