August 28, 2014

The plastic curse in our oceans

I have just returned with a team of scientists from six weeks at sea conducting research in the Great Pacific Garbage Patch — one of five major garbage patches drifting in the oceans north and south of the equator at the latitude of our great terrestrial deserts. Although it was my 10th voyage to the area, I was utterly shocked to see the enormous increase in the quantity of plastic waste since my last trip in 2009. Plastics of every description, from toothbrushes to tires to unidentifiable fragments too numerous to count floated past our marine research vessel Alguita for hundreds of miles without end. We even came upon a floating island bolstered by dozens of plastic buoys used in oyster aquaculture that had solid areas you could walk on.

Plastics are now one of the most common pollutants of ocean waters worldwide. Pushed by winds, tides and currents, plastic particles form with other debris into large swirling glutinous accumulation zones, known to oceanographers as gyres, which comprise as much as 40 percent of the planet’s ocean surface — roughly 25 percent of the entire earth.

No scientist, environmentalist, entrepreneur, national or international government agency has yet been able to establish a comprehensive way of recycling the plastic trash that covers our land and inevitably blows and washes down to the sea. In a 2010 study I conducted of the Los Angeles and San Gabriel Rivers, we extrapolated that some 2.3 billion pieces of plastic — from polystyrene foam to tiny fragments and pellets — had flowed from Southern California’s urban centers into its coastal waters in just three days of sampling.

The deleterious consequences of humanity’s “plastic footprint” are many, some known and some yet to be discovered. We know that plastics biodegrade exceptionally slowly, breaking into tiny fragments in a centuries-long process. We know that plastic debris entangles and slowly kills millions of sea creatures; that hundreds of species mistake plastics for their natural food, ingesting toxicants that cause liver and stomach abnormalities in fish and birds, often choking or starving them to death. We know that one of the main bait fish in the ocean, the lantern fish, eats copious quantities of plastic fragments, threatening their future as a nutritious food source to the tuna, salmon, and other pelagic fish we consume, adding to the increasing amount of synthetic chemicals unknown before 1950 that we now carry in our bodies.

No comments: