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changed much more slowly,” Yokoya- ma says. (Emory University) http://bit. ly/1v9reAf

Floating Plastic Trash Common in Oceans The first global estimate of plastic pol- lution has led researchers to conclude that the smallest and most insidi- ous particles are present throughout the world’s oceans. The new report, published in the journal PLOS ONE, culminates over six years and 50,000 nautical miles of pelagic plastics re- search, the most comprehensive study of its kind to date.

“When The 5 Gyres Institute formed in 2008, we set out to answer a basic question: How much plastic is out there?” says Marcus Eriksen of the institute. “We’ve found microplastic ocean pollution, in varying concentra- tions, everywhere in the world.”

The report estimates that some 5.25 trillion plastic particles weigh- ing about 269,000 tons are floating in the world’s oceans. Previous reports only looked at one size class and thus reported much lower plastic densities in the world’s oceans.

The new research also demonstrat- ed some unexpected findings, namely

a dramatic loss of microplastic from the sea surface in the garbage patches of the five subtropical gyres, large areas of rotating currents where the frag- ments tend to accumulate. In addition, the survey found a wide distribution of the smallest microplastics in remote re- gions of the ocean. Though concentra- tions in the gyres are lower than pre- viously reported, plastics occur nearly everywhere, often far outside of the garbage patches.

Eriksen led a team of nine research- ers from six different countries, includ- ing Capt. Charles Moore, who found the first garbage patch in the North

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Pacific. The researchers contributed data from 24 expeditions studying plastic floating on the sea surface. Mi- croplastics were collected with nets, while floating macroplastics were counted by systematic observations. These data were used to populate a model that assumes plastic enters the oceans from rivers, shipping lanes, and densely populated coastlines. The data and model show that large plastics are abundant near coastlines and degrade in the five subtropical gyres into mi- croplastics, the smallest of which are, surprisingly, present in more remote regions such as the subpolar gyres.

These maps show where the density of plastic debris of various sizes was measured. The count density was measured at 1,571 stations from 680 net tows and 891 visual survey transects for each of four plastic size classes (0.33–1.00 mm, 1.01–4.75 mm, 4.76–200 mm, and >200 mm).

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The garbage patches should thus be characterized not as repositories or final resting places, but as shredders and redistributors of trash, where sunlight (UV), oxidation, embrittle- ment, breakage by waves and frag- mentation by grazing fish all degrade large plastic pieces to tiny fragments. These microplastics are then ejected from the garbage patches through various mechanisms such as foraging and filter-feeding by marine organ- isms, and subsurface currents.

The new research categorized plastic into four size classes: from roughly equivalent to a grain of sand

to a grain of rice to a water bottle and finally anything larger. Using con- servative fragmentation rates, the re- searchers expected to find more small particles than larger ones. Surprising- ly, their model showed that the small- est fragments are less abundant than the next larger size, but more small particles are found outside of the gar- bage patches.

Other research has established that some marine organisms, including seabirds and fish, ingest these toxic plastics and may de-sorb these toxi- cants. “The garbage patches could be a frightfully efficient mechanism for

corrupting our food chain with toxic microplastics,” says Eriksen.

The 5 Gyres Institute, which uses research to motivate change, contends that companies must take responsi- bility for the entire life-cycle of the products they create. Working in col- laboration with multiple government agencies, NGOs, and responsible cor- porations, the 5 Gyres Institute will continue to support campaigns such as its ongoing effort to replace plastic mi- crobeads in cosmetics and toothpastes with biodegradable alternatives. (PLOS ONE) http://bit.ly/1whEgzp; video: http://vimeo.com/113359330

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