Quantcast
Environmental News for a Healthier Planet and Life

Help Support EcoWatch

What Ocean Microplastics Are Really Made of

Oceans

Magnus Larsson / iStock / Getty Images Plus

By Rachel Kaufman

Humans produce hundreds of millions of tons of plastic every year. As much as 12.7 million metric tons of it ends up in the ocean, where it can transport pathogens, or be mistaken for food by hungry animals.


Some is visible to the naked eye—but not all plastic pollution is obvious.

The ocean is full of microplastics 5 millimeters or smaller, about the size of a pencil eraser. At those small sizes, it can be difficult to identify where the plastic came from. Was that tiny chunk part of a water bottle or a fishing lure?

A new project at NOAA's Northeast Fisheries Science Center in Sandy Hook, New Jersey, aims to find out. Knowing what types of plastics are most common in the ocean could help prevent the pollution in the first place.

Chemical Forensics

More than 60 percent of the debris swirling through the oceans is plastic. But plastics are not all the same. They're made of different chemical building blocks and have different densities. Plastic bags are made of polyethylene, margarine tubs are made of polypropylene. Both are lighter than seawater, so those plastics float. Other plastics are heavier, so they can be found deeper in the water column or sink to the bottom.

It's not just their densities that are different. Different plastics absorb contaminants and disease-causing microbes differently and can have different toxic effects. Knowing which types are most prevalent in what parts of the ocean, "will help us find out what is polluting the environment," said Ashok Deshpande, a research chemist at NOAA's Northeast Fisheries Science Center whose team is among the first to chemically identify ocean plastics using gas chromatography-mass spectrometry. The technique identifies materials based on their component parts, with the goal to create a reference library of plastics, so that scientists can identify contaminants when they're found.

Armando da Costa Duarte, a chemist at University of Aveiro, Portugal, who co-edited an academic book on chemistry and microplastics that included a chapter on mass spectrometry, said that the method is "relatively new" for ocean plastic, but that others have been working toward it. It is "a well-established method of analysis that can bring complementary information" to other techniques for chemically identifying plastic, he said by email.

It's another tool in scientists' toolbox to figure out just what's out there—and what to do about it.

So far, the NOAA project has identified various plastics from the Gulf of Mexico and beaches in Hawaii, Alaska and New Jersey. Nigel Lascelles, a NOAA Educational Partnership Program scholar, worked on the initial analyses.

The team successfully identified all but one of the scraps of collected plastic, and then some—the researchers also detected toxins like phthalates, commonly used to soften some plastics, flame retardants and—no joke—cannabidiol, a naturally occurring component of cannabis. "I don't know how that would be on plastic," Lascelles said.

Urgent Work

Next, the team plans to examine the contents of a sea turtle's stomach and samples from seabirds that ate microplastics. The chemical analysis could help identify which plastics wildlife are consuming most often. The NOAA scientists are also hoping to determine the origin of ocean microplastics by looking at additives. "Products used for human consumption may not have additives like flame retardants," Deshpande said, which could help differentiate a tossed soda bottle from an industrial component like an aircraft interior.

The work is more urgent than ever, with research showing upwards of 236,000 metric tons of microplastic particles floating on the surface of the ocean, a tiny fraction of all the plastic out there. Sea life eats a lot of it. A recent study found that baby sea turtles are dying by ingesting tiny pieces of plastic that cause intestinal blockage or nutritional deficiency. Another study, from 2017, found that small fish like anchovies are eating microplastic but possibly surviving long enough to be eaten by larger predators. That's a problem since plastics—and their associated chemical contaminants—could build up in the bodies of larger fish. Knowing more about where the plastics came from and what they are made of can help improve habitat management for fish and other marine life.

What remains clear is that when it comes to plastics in the ocean, our knowledge is just scratching the surface. "What science has analyzed so far," Deshpande said, "is a fraction of the total plastic waste into the ocean."

EcoWatch Daily Newsletter

Dr. Mark Brunswick (2R), Vice President of Regulatory Affairs and Quality, walks through the lab at Sorrento Therapeutics in San Diego, California on May 22. ARIANA DREHSLER / AFP / Getty Images

By Julia Ries

Around the world, there have been several cases of people recovering from COVID-19 only to later test positive again and appear to have another infection.

Read More Show Less

By Samantha Hepburn

In the expansion of its iron ore mine in Western Pilbara, Rio Tinto blasted the Juukan Gorge 1 and 2 — Aboriginal rock shelters dating back 46,000 years. These sites had deep historical and cultural significance.

Read More Show Less
Meadow Lake wind farm in Indiana. Anthony / CC BY-ND 2.0

By Tara Lohan

The first official tallies are in: Coronavirus-related shutdowns helped slash daily global emissions of carbon dioxide by 14 percent in April. But the drop won't last, and experts estimate that annual emissions of the greenhouse gas are likely to fall only about 7 percent this year.

Read More Show Less
Andrey Nikitin / iStock / Getty Images Plus

By Adrienne Santos-Longhurst

Plants are awesome. They brighten up your space and give you a living thing you can talk to when there are no humans in sight.

Turns out, having enough of the right plants can also add moisture (aka humidify) indoor air, which can have a ton of health benefits.

Read More Show Less
A bald eagle chick inside a nest in Rutland, Massachusetts. Massachusetts Division of Fisheries and Wildlife
A bald eagle nest with eggs has been discovered in Cape Cod for the first time in 115 years, according to the Massachusetts Division of Fisheries and Wildlife (Mass Wildlife), as Newsweek reported.
Read More Show Less
The office of Rover.com sits empty with employees working from home due to the coronavirus pandemic on March 12 in Seattle, Washington. John Moore / Getty Images

The office may never look the same again. And the investment it will take to protect employees may force many companies to go completely remote. That's after the Centers for Disease Control and Prevention (CDC) issued new recommendations for how workers can return to the office safely.

Read More Show Less

Trending

Frederic Edwin Church's The Icebergs reveal their danger as a crush vessel is in the foreground of an iceberg strewn sea, 1860. Buyenlarge / Getty Images

Scientists and art historians are studying art for signs of climate change and to better understand the ways Western culture's relationship to nature has been altered by it, according to the BBC.

Read More Show Less