Tuesday, April 7, 2009

Garbage Out, Garbage In

For some reason, I’ve run across several references to the great Pacific garbage patch in the past couple of weeks, the most recent being a mention on “Real Time with Bill Maher” (towards the end of this “New Rules” segment). The patch is the result of floating garbage, mostly plastic, being caught in the currents that encircle the North Pacific Gyre.

I first learned about the phenomenon from a friend who used to sail from California to Hawaii twice per year in the late 1980s and early 1990s. In 2003, an article in Natural History magazine brought the accumulating garbage back to my attention to wider public consciousness.

Today, the patch is variously described as one or two times the size of Texas and is primarily (80 percent) composed of debris blown or washed off of land. The rest probably originated from shipping containers lost at sea. Charles Moore, who has been sailing into the gyre for much of the past decade to study the amount, distribution and type of garbage there, believes it contains more than 100 million tons.

That’s right, out there in the middle of the Pacific, days from land, you can find garbage of almost every conceivable shape and purpose—including raw, pre-consumer plastic pellets that never made it into a recognizable product. It just went straight from the manufacturer to the ocean. Now THAT’S cutting out the middleman.

The impacts this and other so-called marine debris is having on birds and marine mammals have been well documented. NOAA even maintains a program devoted specifically to understanding, controlling and removing large marine debris from U.S. coasts and waters. I also once had the opportunity to edit a series of dispatches by then-journalism-student Joe Spring in which he collected and examined just a fraction of the trash that accumulated on one tiny, deserted beach in Northwest Hawaii. Some of the most frightening things out there are discarded or lost fishing equipment—including miles-long “ghost nets” that continue to float through the oceans capturing marine life for years.

As horrendous as the larger debris can be, the increasing abundance of microplastic—tiny plastic particles between 5 and 0.5mm in diameter—dispersed throughout the oceans are an even more insidious problem. These are formed when large pieces break down through physical or chemical processes. In some areas, plastic debris in the water column outweighs the amount of plankton several times over.

These particles can either adsorb pollutants onto their surface, transporting the chemicals well beyond a localized spill, or they can leach their own toxins into the water. Plankton and other organisms at the base of the food chain then consume persistent organic pollutants (POPs), the lipophilic, or “fat-loving” substances, in the plastics. Because we consume marine organisms higher up the food chain indirectly (through feed given to livestock) and directly, we are now not only littering our own nest, we are now effectively eating our own garbage. Bio-accumulated poetic justice.

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