Marcus Eriksen has always had a thing for trash. As a teenager in New Orleans, he literally surrounded himself with it. He liked to dumpster dive long before it became cool, spending hours at the local dump and watching a massive mechanical claw feed refuse to an incinerator.
But when Eriksen first considered dedicating his professional life to understanding global garbage and where it goes, he found few published studies.
“I could count the research papers on ocean trash on two hands,” Eriksen says. So in 2009, several years after finishing his Ph.D. in science education at the University of Southern California in Los Angeles, he and his wife, Anna Cummins, founded 5 Gyres, an institute devoted to studying plastic pollution in the sea.Since then, Eriksen and his collaborators have sailed more than 35,000 miles, counting trash. On December 10 in PLOS ONE , the team published a new estimate of the ocean’s floating plastic load: 5.25 trillion pieces spanning a range of sizes and together weighing almost 270,000 metric tons.
The researchers worked particularly hard to quantify the tiniest flecks of plastic, those smaller than a grain of rice. These specks constitute about 92 percent of the floating plastic particles, the team found, and a significant fraction of plastic mass in the surface ocean.
Although that’s a lot of trash, it’s actually less than Eriksen and other scientists expected (SN: 8/9/14, p. 9). The smallest fragments either sink or get eaten, he says, and that’s a problem.
Microplastics at sea “are hazardous waste,” says Eriksen, who is 47. They absorb pollutants and cycle through the marine food web. “Paper is biodegradable, metals will oxidize, glass is benign — it’s plastic that is a very different animal,” he says.
Eriksen isn’t content with simply tallying the damages. He also tries to raise awareness of the problem, sometimes in unconventional ways. In 2008, he sailed from Los Angeles to Hawaii on a raft made from the salvaged body of a Cessna airplane, buoyed by 15,000 plastic water bottles.
“It was more of an adventure than I bargained for,” Eriksen says. The 88-day voyage took nearly three times as long as expected, and he almost ran out of food. Then one day, Eriksen caught a fish — a foot-long rainbow runner.
The fish fed his hunger and his drive: When he cut the rainbow runner open, he found its belly full of plastic.