Perreault Magazine - 74 -
ARCTIC sea ice and microplastic pollution
Microplastics have been found polluting oceans and lakes around the world over the past decade, but not as far north as the Arctic Ocean. Now, significant amounts of tiny fragments of plastic have been found in Arctic ice. Researchers have discovered that Arctic sea ice is contaminated with tiny fragments of plastic from run-off, dumped garbage and fishing gear. Dr. Rachel Obbard, an assistant professor in the Thayer School of Engineering at Dartmouth College in New Hampshire, was studying sea-ice cores when she was surprised to find a high concentration of plastic in the ice. Sea ice naturally takes up particles from the water as it forms, and Dr. Obbard thinks that the sea ice is acting as a sponge, collecting plastic that enters the Arctic Ocean from the Atlantic and Pacific. As multi-year sea-ice disappears, this reservoir of frozen plastic is likely to be released back into the Arctic Ocean.
Scientists are concerned about these particles because they tend to absorb and concentrate other pollutants in the environment, which then enter the food chain when animals swallow the microplastics. Dr. Obbard and her team discovered that Arctic sea ice was contaminated with microplastics by accident when she melted the ice in order to count microscopic algae that live under the ice. "I was really shocked and saddened....
I guess I, like most people, still consider the Arctic to be a pristine and remote area and clearly, our pollution has reached even it." When the melted ice was filtered, the filter paper trapped not just sand and diatoms, but microplastics as well. "I saw a lot of small threads, some solid chunks in oranges and reds, and a bunch of small blue nodules," Obbard recalled.
Credits for slides are as follows:
"Site 11 - PE" is polyethylene (the triangular orange piece)
Photo credit to S. Sadri/R.C. Thompson, Plymouth University
"HOTRAX Site 26 Tube 115A Image 008b" In the top right quadrant of the photo is a piece shaped like a guy running beneath a red rainbow.This piece was tested and found to be polyester.
Photo credit to Y.-Q. Wong/A. Khitun/R. Obbard, Dartmouth College
"map6wlabel" shows the locations of the ice cores we examined for this study
Photo credit: R. Lieb-Lappen/Thayer School of Engineering at Dartmouth College