Great Lakes Plastic Pollution.JPG

In this 2012 photo provided by 5gyres.org is a sample collected in eastern Lake Erie showing tiny bits of plastic on a penny. Scientists discovered masses of floating plastic particles in Lakes Superior, Huron and Erie last year. This summer, theyAC/AAre widening the search to Lakes Michigan and Ontario. They are trying to determine whether fish are eating the particles, which may come from city wastewater, and passing them up the food chain to humans.

((AP Photo/Courtesy 5gyres.org, Carolyn Box))

In this 2012 photo provided by 5gyres.org, Sherri Mason, right, a chemist with State University of New York at Fredonia and one of the project leaders, works aboard a research vessel on Lake Erie with a device that skims the water surface collecting samples in finely meshed netting. Scientists discovered masses of floating plastic particles in Lakes Superior, Huron and Erie last year. This summer, theyâÂÂÂÂre widening the search to Lakes Michigan and Ontario. They are trying to determine whether fish are eating the particles, which may come from city wastewater, and passing them up the food chain to humans.

GRAND RAPIDS, MI — Your face wash might be giving you freshly exfoliated skin, but it also could be harming the Great Lakes.

Tiny plastic particles have been proliferating in the massive fresh water system, worrying researchers who fear they could be harming the environment and entering the food chain.

Having already found the "microplastics" in Lakes Erie, Huron and Superior, a team will set sail on Lake Michigan this week to search for the tiny bits.

The minuscule beads are not floating en masse in the lakes, but they are captured when researchers drag special nets that also nab other small plants, fish and particles.

Sherri Mason, the team's principal investigator, said "microbeads" in consumer products such as face wash, toothpaste and mouth wash are a "significant contributor."

The microbeads are added by manufacturers to produce a scrubbing or exfoliating effect in personal hygiene products, Mason said.

"They're so small that they make their way directly into the wastewater treatment process, and into the oceans and lakes," said Mason, a professor at the State University of New York at Fredonia, which sits near Lake Erie.

Mason has teamed with researchers in Wisconsin to determine whether microscopic phytoplankton and fish are eating the plastics and, therefore, putting them in the food chain.

This could be problematic for humans, Mason said, because chemical pollutants already in the lake have been found in some tests to cling to the microplastics.

It also is worrisome, The Associated Press noted, for native fish and aquatic organisms already threatened by invasive species and "man-made contamination."

"(Fishing is) one of our major tourism attractions throughout the Great Lakes region," Mason said. "If we can show that these things are affecting the fish, I think that's really going to create change."

Last year, Mason's team trawled Lakes Erie, Huron and Superior to determine whether the problem warranted investigation.

To collect the samples, researchers use what it called a Manta Trawl, so-called for its similarity to a large manta ray. The trawl is designed to catch anything bigger than a third of a millimeter in diameter, Mason said.

The net is dragged along the surface for half-hour stretches, and its contents are then collected and stored. They are analyzed in Mason's lab after each outing.

Some 90 percent of the plastics found last year by the team originated in Lake Erie, which is the smallest and shallowest of the lakes, Mason said.

That gives experts pause, because it could mean more plastics are lurking in the other, larger lakes — not to mention the ocean — than what researchers ultimately find.

Mason's team took 21 samples during last year's expedition. It takes roughly a day to pore over each sample for plastics.

Having scoured Lake Ontario in July, and a 21-day expedition set to begin later this week on Lake Michigan, Mason expects to collect between 50 and 75 samples this time.

"That would take us three or four months just to go through the sample processing," she said.

The Lake Michigan expedition is set to embark Friday, Aug. 2, from St. Ignace. The team expects to reach Chicago by Aug. 7.

Between Aug. 8 and Aug. 10, the group will trawl southern parts of Lake Michigan, near Benton Harbor. After that, the ship will sail back toward Chicago before heading north.

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