A team at Scripps Institution of Oceanography documented the big rise when they trawled the waters off California. And, it compared the latest plastic "catch" with previous data for the region, the 'Biology Letters' journal reported.
"We did not expect to find this. When you go out into the North Pacific, what you find can be highly variable. So, to find such a clear pattern and such a large increase was very surprising," team leader Miriam Goldstein told 'BBC'.
All the plastic discarded into the ocean that does not sink will eventually break down. Sunlight and the action of the waves will degrade and shred the material over time into pieces the size of a fingernail, or smaller.
An obvious concern is that this micro-material could be ingested by marine organisms, but the Scripps team has noted another, perhaps unexpected, consequence.
The fragments make it easier for the marine insect Halobates sericeus to lay its eggs out over the ocean. These "sea skaters" or "water striders" -- relatives of pond water skaters -- need a platform for the task. (MORE)