Plas­tic de­bris wide­spread on ocean sur­face

The Standard Journal - - State & National - By MAL­COLM RIT­TER

NEW YORK (AP) — Plas­tic junk is float­ing widely on the world’s oceans, but there’s less of it than ex­pected, a study says.

Such ocean pol­lu­tion has drawn at­ten­tion in re­cent years be­cause of its po­ten­tial harm to fish and other wildlife.

The new work drew on re­sults from an around-the­world cruise by a re­search ship that towed a mesh net at 141 sites, as well as other stud­ies. Re­searchers es­ti­mated the to­tal amount of float­ing plas­tic de­bris in open ocean at 7,000 to 35,000 tons.

An­dres Cozar of the Univer­sity of Cadiz in Spain, an au­thor of the study, said that’s a lot less than the 1 mil­lion tons he had ex­trap­o­lated from data reach­ing back to the 1970s.

The new es­ti­mate in­cludes only float­ing de­bris, not plas­tic that may re­side be­neath the sur­face or on the ocean floor.

Of the plas­tic pieces caught by the ship’s net, most were less than about a fifth of an inch long. Some float­ing pieces start out small, like the mi­crobeads found in some tooth­pastes and cos­met­ics or in­dus­trial pel­lets used to make plas­tic prod­ucts. Other small pieces can re­sult when wave ac­tion breaks up larger ob­jects, like bot­tle caps, de­ter­gent bot­tles and shop­ping bags.

The net turned up fewer small pieces than ex­pected, and it will be im­por­tant to fig­ure out why, re­searchers said. Per­haps the tini­est pieces are be­ing eaten by small fish, with un­cer­tain ef­fects on their health, Cozar said in an email.

While the re­search showed plas­tic to be dis­trib­uted widely, con­cen­tra­tions were high­est in five ar­eas that were pre­dicted by ocean cur­rent pat­terns. They are west of the U.S., be­tween the U.S. and Africa, west of south­ern South Amer­ica and east and west of the south­ern tip of Africa.

Plas­tic de­bris from land reaches the ocean mostly through storm wa­ter runoff, the re­searchers said in their re­port, re­leased Mon­day by the Pro­ceed­ings of the Na­tional Academy of Sci­ences.

Kara Laven­der Law, who stud­ies plas­tic pol­lu­tion at the Sea Ed­u­ca­tion As­so­ci­a­tion in Woods Hole, Mas­sachusetts, said the study pro­vides the first global es­ti­mate she knows of for float­ing plas­tic de­bris. The es­ti­mate ap­pears to be in the ball­park, given the re­sults of prior re­gional stud­ies, said Law, who didn’t par­tic­i­pate in the new work.

“We are putting, cer­tainly by any es­ti­mate, a large amount of a syn­thetic ma­te­rial into a nat­u­ral en­vi­ron­ment,” Law said. “We’re fun­da­men­tally chang­ing the com­po­si­tion of the ocean.”

The im­pact on fish and birds is hard to gauge be­cause sci­en­tists don’t un­der­stand things like how much plas­tic an­i­mals en­counter and how they might be harmed if they swal­low it, she said.

(AP Photo/NOAA Pa­cific Is­lands Fish­eries Sci­ence Cen­ter)

This 2008 photo pro­vided by NOAA Pa­cific Is­lands Fish­eries Sci­ence Cen­ter shows de­bris in Hanauma Bay, Hawaii. A study re­leased by the Pro­ceed­ings of the Na­tional Academy of Sci­ences on Mon­day, June 30, 2014, es­ti­mated the to­tal amount of float­ing...

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