Wednesday, 19 December 2007


There is a large part of the central Pacific Ocean that no one ever visits and only a few ever pass through. Surprisingly, this is the largest ocean realm on our planet, being about the size of Africa, over ten million square miles. A huge mountain of air, which has been heated at the equator, and then begins descending in a gentle clockwise rotation as it approaches the North Pole, creates this ocean realm. The circular winds produce circular ocean currents which spiral into a center where there is a slight down-welling.

Because of the stability of this gentle maelstrom, the largest uniform climatic feature on earth is also an accumulator of the debris of civilization. Anything that floats, no matter where it comes from on the north Pacific Rim or ocean, ends up here, sometimes after drifting around the periphery for twelve years or more. Historically, this debris did not accumulate because it was eventually broken down by micro organisms into carbon dioxide and water. Now, however, in our battle to store goods against natural deterioration, we have created a class of products that defeats even the most creative and insidious bacteria. They are plastics.

This area is the size of a continent, and it’s filling up with floating plastic waste. This has effected all types of creatures that inhabit this area. Circular ocean currents with contrary rotation create long lines of material, visible from above as streaks on the ocean. Normally these are formed by planktonic organisms or foam, but recently one was discovered made of plastic. Everything from huge hawsers to tiny fragments were formed into a miles long line, hundreds of pounds of netting of all types bailed together in this system along with every type and size of debris imaginable. There is, however, an even darker side to pollution of the ocean by ubiquitous plastic fragments.

As these fragments float around they accumulate the poisons that we manufacture for
various purposes that are not water-soluble. It turns out that plastic polymers are sponges for DDT, PCBs and nonylphenols -oily toxics that don’t dissolve in seawater. Plastic pellets have been found to accumulate up to one million times the level of these poisons that are floating in the water itself. These are not like heavy metal poisons which affect the animal that ingests them directly, rather, they are what might be called second generation toxics. Animals have evolved receptors for elaborate organic molecules called hormones, which regulate brain activity and reproduction. Hormone receptors cannot distinguish these toxics from the natural estrogenic hormone, estradiol, and when the pollutants dock at these receptors instead of the natural hormone, they have been shown to have a number of negative effects in everything from birds and fish and, as if you hadn't guessed, to humans.

We can grow pesticide free organic produce, but can nature still produce a pesticide free organic fish? After what scientists witnessed first hand in the Pacific perhaps not. The battle to change the way we produce and consume plastics has just begun but it is essential that it be fought now. Plastics do have their place in creation, but not in the sea or buried in the ground.

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