Plastic Wave: The Effect of Microplastics on our Planet

By Mickey Snowdon, Communications Liaison for The Collider.

We are all living in plastic. Most of it is obvious—food packaging, takeout bags and containers, polyester clothing—but there’s an alarming amount that we can’t easily see. These tiny particles are called microplastics. 

According to NOAA, microplastics are less than five millimeters long, roughly the size of a sesame seed. Microplastics may be the most ubiquitous pollutant on Earth. According to Dr. David Hastings, a recently retired professor of marine science at Eckerd College and the University of South Florida in St. Petersburg, “Wherever we look, we find microplastics, whether it’s in the Arctic or the deepest ocean trench. They’re even in salt and beer.” These particles primarily stem from the production of plastics, lint from synthetic clothing, bath and body products, and from the degradation of larger pieces of plastic over time. 

Microplastics range in size from that of a grain of sand to something that can’t even be seen under a microscope (these are known as nanoparticles). One common form of microplastics are microbeads—tiny pieces of plastic less than a millimeter thick that are added to bath products such as face washes, soaps, and toothpaste as an exfoliant. According to an article published in the Environmental Science and Technology journal, microbeads are persistent, toxic, and they bioaccumulate, meaning they are passed through the food chain.

Microplastics are unwittingly flushed down toilets and washed down drains every day. Too small to be filtered by wastewater treatment plants, they enter streams and rivers which carry them into oceans. They also infiltrate open land and fields in the form of sludge when the organic byproducts of wastewater treatment plants are applied to crops as fertilizer. Former President Obama created the Microbead-Free Waters Act of 2015 which outlawed microbeads, but Hastings speculates that many of these products still remain on store shelves throughout the world.

The impacts of microplastics on aquatic life begin with filter-feeding organisms, such as barnacles, clams, whales, mussels, sponges, and crabs, that filter water to feed. We’re not talking about just a little bit of water, either; one oyster can filter up to 50 gallons of water per day to feed itself. Hastings explains that while 50 gallons of water would normally contain quite a bit of plankton for the oyster to eat, it will get a false sense of being full if it consumes a substantial amount of plastic from the water. 

Persistent organic pollutants (POPs)—chemicals that don’t easily break down, such as PCBs, DDT, and dioxins—stick to the surface of microplastics, a process known as adsorption. When a filter-feeder or a fish consumes one of these contaminated plastics, the chemicals can desorb from the plastic and become stored in the organism’s fatty tissue. As fish eat other fish, these POPs concentrate as they move through the food chain, a process called biomagnification. One Environmental Health Perspectives article posits that these chemicals may even make their way into humans when we eat contaminated seafood.

Hastings says that marine scientists are interested in how quickly microplastics are egested out of an aquatic organism after they’ve been ingested. “If it goes in and out quickly, there will be less of an impact,” he says. But if that piece of plastic can’t be removed from an organism,  Hastings says it can block its digestive tract. “It’s hard to tell what the impact of that is on the organism, but it can’t be good,” he explains. A Scientific American article posits that microplastics typically don’t just pass through the digestive systems of organisms, but rather rub up against internal organs, causing inflammation. In some cases, they can even pass into the bloodstream or other organs.

While Hastings says that there isn’t enough evidence to support the claim that microplastics could be contributing to warmer ocean temperatures, he cites a study conducted by Florida State University that examined the effects of microplastics on sea turtle hatchlings. When loggerhead sea turtles lay eggs, the temperature of the sand determines their sex. The study found that since plastics retain more heat than sand, an increase in microplastics in sea turtle beach nests could result in higher nest temperatures, thus influencing the turtles’ sex. Hastings points out that increased overall temperatures from climate change could exacerbate the heat retained by microplastics.

Plastic production has been on the rise since the 1950s and doesn’t appear to be slowing down anytime soon. As Finn Digman points out in his inaugural Mind Your Plastic post, the Plastic Industry Association is actually pushing for an increase in single-use plastic bags to fight the spread of the Coronavirus, a point that Digman says is illogical. The US is responsible for discarding over 100 billion plastic bags a year—the equivalent of throwing away 12 million gallons of oil. Hastings points out that as our country begins to decrease our overall consumption of oil and other petroleum products, there’s a perceived need to find a new market for petroleum-based products. “Increasing our production of plastics will provide the excuse to continue to extract petroleum,” he says.

So what’s the one thing we should all do to reduce our plastic footprint? 

According to Hastings, we need to be better about how we deal with garbage as a society. Less than nine percent of plastics are recycled in the US, which means that nearly all plastics are sent to landfills. Plastics are incredibly durable and do not biodegrade, making it easy for them to travel throughout ecosystems. Plastic bags easily get blown around the world, ending up in the farthest-reaching corners of the planet. Hastings says that reducing the production and usage of single-use plastics needs to be our primary focus. I propose the well-established “Reduce, Reuse, Recycle” model be modified to begin with “Refuse,” because the first step we can take to reduce plastic production is to refuse it at the consumer end.
















​Mickey Snowdon is Communications Liaison at The Collider and a recent graduate of the Master of Liberal Arts and Sciences program at UNC Asheville. He is passionate about reducing plastic waste so that future generations can inherit a cleaner and healthier planet.

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