From the University of California's Scripps Institution of Oceanography:
"There may be a misapprehension ... that if you got out there and stood on the middle of a deck
you'd see nothing but plastic litter from horizon to horizon," said Robert Knox, deputy director for research
at the Scripps Institution.
"It's relatively sparse, and you might or might not see something visible to the human eye at any particular location out there," Knox says. "Certainly one does encounter pieces of plastic stuff that are big enough to see. But the other side of the puzzle is all the little bits and pieces of plastic that you can't even see unless you scoop up a sample of seawater and see what's in there."
"I think it's a little misleading to think of it as a great big island that you could practically get out and walk on, but the point is it's a big area of ocean. So even a few pieces of plastic per square meter amounts to a lot of plastic when you add it up over this enormous ocean area."
Scientists study 'garbage patch' in Pacific Ocean - CNN.com