North American Great Lakes plastic pollution


This video is called Mysteries of the Great Lakes.

From Discovery News:

Great Lakes Filled With Plastic Bits

The world’s largest freshwater ecosystem is added to the list of natural places filled with massive swirls of plastic pollution.

By Emily Sohn

Wed Nov 28, 2012 08:41 AM ET

The Great Lakes are swimming with tiny specks of floating plastic, posing threats to both wildlife and human health.

Adding to years of research that have already documented gyres of plastic pieces swirling in the oceans, the new study is the first to officially add the world’s largest freshwater ecosystem to the list of natural places affected by plastic pollution.

As scientists continue to investigate how much plastic is out there, where it’s coming from and how it’s moving between lakes and from lakes to sea, the findings may eventually offer strategies for mitigating the problem.

“The reality is that all the plastic we see in the environment makes its way into the water, which means it’s making its way ultimately into us,” said Sherri Mason, an environmental chemist at SUNY Fredonia. “What we find in the lakes is coming from us, so we’re the problem but we’re also the solution.

“I always want to encourage people to be thinking about their own lives and what they can do,” she added. “If they’re not going to go out and clean up the beach, they can find ways to reduce plastic in their own lives, especially single-use plastics. Forgo the straw. Stop buying disposable plastic bottles. Bring reusable bags so you don’t need to take plastic bags home.”

For decades, scientists have been documenting patches of plastic in the oceans that often congregate where circulation patterns push them together. Most of the bulk of that plastic, according to recent work, is made of tiny bits that are often invisible to the naked eye but can end up accumulating in the food chain.

While teaching a course on a boat in the Great Lakes last summer, Mason stared at the water and wondered if the same might be true there. When she returned to land, she searched the scientific literature for studies on plastic in the big lakes — and turned up nothing.

To begin to fill the knowledge gap, she and colleagues used a manta ray-shaped trawl to collect 21 water samples from near the surface of three lakes: Superior, Erie and Huron. The trawl held a mesh net that caught anything larger than a third of a millimeter in diameter. Each sample filtered water along a distance of two miles.

The researchers did their best to free the many water bugs that landed in the net. Back in the lab, they removed seaweed, fish and other non-plastic items. Then they separated plastic bits by size. And they counted and weighed their stash.

From sample to sample, they found a huge variety in concentrations of plastic, ranging from an extrapolated 600 to 650,000 plastic pieces per square kilometer. Two samples yielded particularly high counts. Both were in areas where the topography of the lakes caused water to converge into river-like currents.

She and her team are currently writing up their findings for submission to scientific journals.

Some headlines about the new research have suggested that the Great Lakes plastic counts exceed anything that’s been found in the oceans, but that’s not necessarily accurate. Research cruises have found the equivalent of 12 million pieces per square kilometer in a few samples in both the Pacific and the Atlantic, said Kara Lavender Law, a physical oceanographer at the Sea Education Association in Woods Hole, Mass. Only with more comprehensive surveys will it become clear how extensive the problem is.

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3 thoughts on “North American Great Lakes plastic pollution

  1. Pingback: United States bird conservation in danger | Dear Kitty. Some blog

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