From: Ben Pittenger (benpittenger@earthlink.net)
Date: Tue May 18 2004 - 12:57:08 PDT
Message-ID: <22677238.1084910229204.JavaMail.root@bert.psp.pas.earthlink.net> Date: Tue, 18 May 2004 12:57:08 -0700 (GMT-07:00) From: Ben Pittenger <benpittenger@earthlink.net> Subject: Oh, where have all the plastics gone?
For those of you who cover polymers, here's a little frosting you might want to add to the cake. Although for some this may be old news, it still is one of those pesky little ethics questions that keeps popping up when science takes that subtle little shift into technology and the market. It fits well with a film "Synthetic Sea" which looks at the prevalence of plastic fragments in the Pacific Ocean, and the adverse effects on marine life:
Article from: http://www.guardian.co.uk/waste/story/0,12188,1211297,00.html
STUDY FINDS OCEANS OF OLD PLASTIC
Tim Radford, science editor
Friday May 7, 2004
The Guardian
Humans are smearing the oceans with plastic, according to British scientists who sifted shorelines to find microscopic fragments of stockings, yoghurt pots, rope, shopping bags and bleach bottles everywhere they looked.
The spread of polymer waste has been reported before: researchers have surveyed beaches on uninhabited islands in Antarctica and found plastic cups, polymer sandals and drinks’ bottles.
But Richard Thompson and colleagues at the University of Plymouth reported in Science last week that they looked at apparently clean sand and mud on British beaches, in intertidal estuaries and even under 9 meters of water for evidence of invisible pollution. “We found microscopic fragments almost from the first sample. Since then we have looked at more than 20 sites around the UK and this material has been present at all of them, from Land’s End to the north of Scotland,” he said. “We are finding just as much in remote parts as we are nearer the big centers.”
They found that fragments lf plastic had been ingested by barnacles, which filter water for food, and in lugworms, which burrow in mud, and in tiny crustaceans, which feed on detritus. In plankton samples they found evidence of polymer fibres as small as 30 millionths of a metre.
Plastics wash up on beaches to be repeatedly broken by the pounding waves. The team searched for nylon, polyester, acrylic and six other kinds of polymer with a clear chemical “signature”. But they believe that they have underestimated the spread of human debris.
They could not identify plastics produced more than 20 years ago, and they could not pick up evidence of particles smaller than 20 microns. But they have clear evidence that long after plastic bags, nylon ropes and Tupperware boxes have vanished, their constituent fragments [small pieces] remain. Nobody knows whether this material can get into the food chain: that is the next line of research.
“If we look at the larger plastic debris accumulating on the shore-line, the most common items are things like plastic bags and boxes and packaging and, ironically, they are all items that needn’t be there,” Dr. Thompson said. “So there is a challenge to all of us to reduce the amount of disposable plastic we use, to recycle things as much as possible.”
Happy summer,
Ben
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