But Moret didn’t know what to expect when she went into the Atlantic data going back 22 years. “I had few preconceived notions of what we might find,” she says. “I only had an overwhelming feeling that this quantity of data over so much time was going to tell a fascinating story.”
She went into the basement, where samples were stored, and dug in. For more than a year, she spent her free time compiling preliminary data. That gave her and Law the raw material to apply for and receive a grant to continue the work.
Analyzing data from 6,100 tows in the North Atlantic, Moret and Law found 62 percent had plastic in them. But in a region due east of Charleston, S.C., in the western Sargasso Sea, they found an area that had plastic in more than 80 percent of the tows. It was another area of concentrated plastic soup, much like the one Moore had found in the Pacific.
They say one intriguing thing the long-term data showed is that the amount of plastic in the high-concentration area didn’t increase over time. The world produces 403 billion pounds of plastic annually, according to Houston-based consulting group Chemical Markets Associates. Most plastic breaks down but doesn’t degrade. So it’s reasonable to assume more and more of it has ended up in the oceans.
Law wonders where it’s going. It may be, she says, that it breaks down into pieces so small that they pass through the trawling net. Or it may be that it is changing density, perhaps thanks to hitchhiking organisms, and sinking.
There is some early evidence which suggests that plastic isn’t floating solely on the surface but actually exists throughout the water column. During the SEAPLEX/Kaisei Project cruise last summer, Goldstein says water samples taken at depths of 525 feet and 630 feet both contained plastic debris. They also caught a hatchet fish, a midwater species that never surfaces, that had ingested a plastic particle. “We don’t know how much is down there,” Goldstein says. “But we have some evidence it’s down there.”
A British study by Richard Thompson and his team at the University of Plymouth found a prevalence of plastic pieces called nurdles, which are used in plastic manufacturing, on beaches as well as in the water. These lentil-sized pieces act as magnets for persistent organic pollutants. The same scientists have been tracking plankton collected from the British coast since the 1960s. Their research shows that plankton collected in the 1990s contain three times more plastic than plankton collected in the 1960s. Now the question is whether or not the toxins accumulated by the plastic travels up the food chain and onto your dinner plate.
“We don’t know how much is ingested [by plankton and fish], and we don’t know the damage to the organisms,” Law says. “We’re really far from knowing what that impact is.”
The big question that needs to be answered, she adds, is whether ingesting plastic is causing harm to everything from plankton on up to humans.
For Moore, his foundation continues to analyze the data it has collected. But navigating the debris field on his last voyage was so dangerous that he’s not sure he’ll return. Several times, he had to go over the side of the boat in the middle of the night to free a propeller fouled by plastic debris. His crew passed the time by standing on deck and counting the pieces of debris they could see within 10 minutes. Often, the numbers reached 100 or more.
“This is happening throughout the North Pacific where you can stand on the bow and see for thousands, probably millions, of square miles that phenomenon of plastic being dispersed, having all these little chunks like alphabet letters in alphabet soup. It’s disturbing. It’s distressing,” he says. “It’s just not the way the ocean should be.”