Scientists will be scanning for colorful beads and other Mardi Gras throws that make their way into the Mississippi River after this year's Carnival season.

On the whole, beads are "a drop in the bucket" of plastic pollution, but they are a vivid reminder of the litter that can harm the ecosystem, said Mark Benfield, a professor with the LSU Department of Oceanography & Coastal Sciences.

Benfield's preparing to begin systematically flying a camera-equipped drone over the river — probably around the LSU School of Veterinary Medicine in Baton Rouge — to record floating plastic debris. The professor hopes to be ready in time to catch the Mardi Gras runoff.

To fish, colorful beads and glitter "would look like something pretty good to eat," Benfield said.

Bass, which pluck insects off the surface of the water, are an example of a species that could mistake a bead for food, especially once a chain breaks and individual links make their way downstream, Benfield said.

That's bad news, because plastic is inherently dangerous as it can block digestion or give animals a false sense of fullness. Chemicals known as persistent organic pollutants also cling to bits of plastic, forming them into poison pellets, said Stephen Midway, an assistant professor with the LSU Department of Oceanography & Coastal Sciences.

The pollutants are chemicals created or used in agriculture, industry, disease control and even the burning of medical waste, according to the Environmental Protection Agency.

Of particular concern is microplastic, pieces just millimeters wide or smaller. They can form when larger products break down, though many begin small. Microbeads are used in sandblasting and exfoliates, and bits of plastic are used in synthetic fibers that slough off clothes like "21st-century lint," Midway said.

He is collaborating with states that drain into the Mississippi River from Montana to Pennsylvania. Local agencies send him dead specimens, from bottom-feeding catfish to algae-eating carp to piscivorous gar, so he can cut open their stomachs and see where plastic is entering the food chain.

Midway hasn't collected enough data to form any conclusions yet, but he suspects the issue is not whether plastic is entering the food chain, but how much is already there. Follow-up work could look at whether ingested plastic makes its way to fish meat, where it can be consumed by humans. Because fish — and humans — have all likely eaten some amount of plastic already, it's also worth figuring out if it has any toxic effects, even if the dose isn't large enough to kill, Midway said.

In Baton Rouge, Benfield is still focused on the bigger pieces. His local surveys will look specifically at large, floating plastic. It won't catch things like heavy, sunken PVC pipes, but he hopes to get a representative look at pollution. Not every scrap of litter is as glittery as Mardi Gras flotsam, though, so Benfield is looking to spread some trash on a practice field on campus so he can get used to spotting plastic from his drone's camera before it's time to put it out over the water.

Dusty Kling, head of the Spanish Town Mardi Gras parade, said his organization doesn’t practice any particular anti-littering measures. Rather, krewes rely on attendees to properly dispose of their throws.

But if krewes are looking for environmentally friendly throws, they may someday turn to Naohiro Kato, an LSU assistant professor of biology. He's creating biodegradable beads out of algae.

The algae can be harvested, ground and formed into shapes. They biodegrade in soil after a year or two, the university wrote in a statement.

The lingering problem is cost.

The first batch of 3,000 necklaces is expected to run about $40,000 — or $13 each. Kato believes costs will decrease dramatically in subsequent production runs, with each necklace dropping in price to $1 or less.

Follow Steve Hardy on Twitter, @SteveRHardy.