Microplastics: A Macro Problem for Our Oceans

Ever wonder where those little plastic beads in your face wash end up? Or what happens to all the plastic bottles that don’t wash up on your local beach? Well, they may end up in one of the five oceanic garbage gyres, or they may just wander about in the water column or on the surface for up to a few hundred years. Our love for all things plastic has left the ocean chock full of the stuff — and it’s not going anywhere.

A 2014 study estimates that there are at least 5.25 trillion plastic particles in our oceans waters, and another predicts that we will have more plastic in our ocean than fish (by weight) by 2050. While the overuse of plastic in everyday products has been a contentious topic for years, discussion of the plastic problem has recently grown to include microplastics. These tiny tidbits of trash have a habit of sticking around for far longer than we ever intended and they’re adding up quickly. Despite a gloomy outlook, scientists and activists from across disciplines are thinking big and pursuing some very innovative projects to help solve this problem!

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Microplastics collected from a freshwater stream in Florida. Source.

The Low Down on Puny Pollutants

Microplastics come in two types: primary microplastics, which were manufactured to be tiny, and secondary microplastics, which are remnants of large plastics past (as pictured above).  Primary microplastics often include the beads in health and cosmetic products, but can also come from less conspicuous sources, like synthetic fleece or nylon clothing, which sheds microfibres with each machine wash. Secondary microplastics are the fated end products of all large plastics. As beach litter washes out with the tide, or cruise ships lose garbage overboard, these products move out to the sea where they are broken down by waves, ocean chemistry, and sun exposure.

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Photo’s Source. Caption: Face wash containing microbeads.

Plastics in the Ocean

Despite a diverse range of origins, most of these plastics wind up in the ocean where they bear a striking resemblance to food for inhabiting organisms. While large pieces of plastic can strangle and choke marine vertebrates, microplastics threaten smaller organisms like copepods and rotifers that ingest them. These now plastic-containing organisms then become food for many organisms higher up on the food chain. This has severe consequences for hungry animals, that inadvertently fill their bellies with this non-nutritious mass. The sheer amount of space plastic takes up inside the stomach can be fatal, since the plastic can’t be digested and leaves little or no space for real food.

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A deceased albatross with all of the plastics found in its digestive tract. Source.

Besides the mechanical effects of blocking up organisms’ digestive tracts, these timeless buggers are potentially poisonous once ingested. The chemical structure of plastics makes them quite good at attracting harmful chemicals in the ocean. Chemicals aggregate on the surface of plastic particles, so broken down plastic pieces, with greater surface area than their larger parent materials, accumulate more harmful chemicals. Once eaten, microplastics can remain in the gut of the animal and may release these chemicals, which opens the door for effects like biomagnification as plastic-containing organisms are eaten by predators. This build up of harmful substances as they move up the food chain can have serious consequences for apex predators, like it did for bald eagles back when DDT was a thing.

In case you forgot that humans are apex predators, a recent study suggests that these chemicals often end up on our dinner plates! The authors found that two-thirds of the seafood species and one-third of the shellfish sampled from California markets contained microplastic debris. While the risks associated with human microplastic consumption are still being studied, the risks they pose to marine life indicate that, maybe, watching your daily plastic intake could be a good move.

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A fish market in Rochester Image source.

Public Participation, Garbage Grabbers, and Fervent Filtration

Citizen science projects like the Global Microplastics Initiative and International Pellet Watch allow people all over the world to contribute to our understanding of the microplastic epidemic. By encouraging people to collect and quantify their ocean plastic findings, we are able to get an idea of regional variation in microplastic density and type. Shoreline cleanups all over the world have brought this effort to the land-sea boundary. Though these events mostly focus on larger items, removing big plastics before they break down is the best way to avoid more microplastics in the ocean. It also spreads awareness and generates enthusiasm by giving plastic collection a sort of scavenger hunt appeal!

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Participant in an event held by the Great Canadian Shoreline Cleanup in Vancouver. Source.

Alongside efforts to unite the global cause, scientists and concerned citizens are developing novel technologies to actually collect all of that plastic. Twenty-year-old Boyan Slat gained worldwide notoriety in 2014 for his proposed “Motherboard,” an oceanic vessel that targets gyre-generated garbage patches, which utilizes ocean currents to catch, concentrate, and remove plastics at a large scale. Last year, another group of scientists from the United Kingdom introduced a similar machine called the SeaVax, that uses wind and solar power to move around and suck up plastic for removal. While scientists are skeptical of the durability and efficacy of these methods, with additional development, this type of grand-scale thinking might get us closer to a cleaner ocean.

Though these large scale clean up efforts are inspiring and exciting in a sci-fi sort of way, the most important thing we can do to reduce the amount of plastic in the ocean is to stop using it. In a TED Talk about his plastic reduction business centered on social justice, David Katz uses the metaphor of an overflowing kitchen sink to urge people to “turn off the tap” on ocean plastics. Many plastic reduction movements are helping people find small ways to cut back on plastic in their lives, and most of them are easy! A lot of the plastic we use every day doesn’t even require an alternative — it’s just entirely unnecessary. Plus, dermatologists say quitting the drinking straw might save you from wrinkles too. Talk about a win-win! The public movement for plastic reduction is accelerating and larger entities are catching on. At least two governments have banned cosmetic microbeads since we started to learn about microplastics, and clothing retailers like Patagonia and MEC are invested in decreasing their contribution to ocean plastics.

If you’re pumped about plastic [reduction] and want to start moving toward a plastic-free lifestyle, consider taking one of these pledges and get involved with a local clean up group! You’ll be a re-usable bag toting, metal water bottle using, card-carrying ocean steward in no time.

About the author:

image03 Kaleigh Davis is a lab manager in the biology department at the University of Central Florida. She graduated from the Odum School of Ecology in 2015 and is a lover of all things aquatic. She is a student at the University of British Columbia pursuing a PhD in marine ecology. Other life goals of hers include beating Oprah’s marathon time and learning to do a headstand. For now you can find her sipping on coffee at all hours of the day or zigzagging around town watching birds overhead. Get in touch with Kaleigh at kaleighedavis@gmail.com. More from Kaleigh Davis.