Plastic pollution is more complex than you think
On January 10, 1992, due to a storm in the middle of the Pacific Ocean, a container of 28,800 yellow rubber ducks, red beavers, blue turtles, and green frogs was lost.
Many of the ducks ended up in the North Pacific Gyre, and some got trapped in polar ice.
Gyres are rotating ocean currents where waste accumulates. There are 5 major gyres, and many famous photographs have been taken of the massive garbage patches that have formed at their centers.
Plastic pollution is getting out of hand.
A truckload of plastic waste is being tipped into the ocean every minute. And it is predicted 2 truckloads per minute by 2030 and 4 truckloads by 2050. This means that the sea will contain more plastic than fish by weight in 2050.²
But it is a myth to believe that plastic from these large plastic islands stays afloat.
There are about a few hundred thousand tons of plastic on the surface of the ocean. This is a huge number, but this is only about 1% of the estimated 8 million tonnes of plastic scientists believe is dumped into the ocean every year.⁶
So you may wonder, where is the remaining 99% of plastic?
Well, the majority of plastic stays close to shore, floating from one coastline to the next. But a lot of the plastic ends up on the seafloor in the form of microplastics, tiny pieces of plastic that are less than 5 mm in length, or macroplastics, pieces larger than 5mm.
While some plastics sink immediately, others stay afloat. Yet these plastics will likely sink as well because over time, plastic breaks down into tiny pieces and when algae are attached to them, they sink.
For example, plastic water bottles, which are made out of polyethylene terephthalate (PET), sink immediately. But with a cap on, it might get pulled into a gyre. But bottle caps themselves, made out of High-density polyethylene (HDPE), don’t sink, which is why it’s more likely for people to find bottle caps than plastic bottles on beaches.
Moreover, there are two kinds of microplastics: Primary and secondary microplastics. Primary microplastics are tiny pieces of plastics that were produced small— think personal care products.
But the majority of microplastics are secondary microplastics, which means that they are formed from bigger pieces of plastics that become smaller and smaller due to fragmentation. Fragmentation occurs physically rather than chemically. Sunlight exposure, oxygen, wave action, ultraviolet radiation, and friction all cause fragmentation.
For example, rubber ducks don’t just look the same from the time they are put out into the ocean to when they are collected.
This is where the problem gets complex. Almost all plastics out there right now will slowly be broken down until they are nearly impossible to collect. And all plastic ever produced is still out there somewhere.
Every time you wash a nylon shirt in the washing machine, you create microplastics. Face masks discarded in the street make their way to rivers and oceans where they are broken down due to friction and wave action and become microplastics. Driving causes tires to wear which creates microplastics.
But how big is this problem?
We don’t know exactly how much plastic is out there right now, but scientists often quote a 2010 estimate that the 192 countries in the world with coastlines are together responsible for about eight million tons.⁵
Plastic is accumulating at an alarming rate. In 1950, the world produced only 2 million tonnes per year. Since then, annual production has increased nearly 230-fold, reaching 460 million tonnes in 2019.⁴ The recent COVID pandemic only worsens the problem as it increased global single-use plastic production for medical devices and personal protective equipment.
Why does this matter?
Well, these tiny pieces of plastic end up in animals mistaking plastics for food.
“The record is 276 pieces of plastic inside of one 90-day old chick. And that plastic when we weighed it out, counted for 15% of that bird’s body mass. If we translate that into human terms, that would be equivalent to having around 6 or 8 kilos of plastic inside of your stomach. That’s equivalent to about 12 pizzas.”
— Jennifer Lavers (2017 United Nations Documentary, Plastic Ocean)
But plastic pollution isn’t a problem that only affects animals. It affects humans as well.
Microplastics have been found in the water we drink, our food, salt, honey, beer, and sometimes even in the air we breathe. Plastic pollution is a growing health and environmental concern.
Cancer, impaired reproductive activity, decreased immune response, and malformation in animals and humans are some of the effects of the consumption of plastic.
There are also additives like BPA, softeners, and fire retardants which are dangerous to humans.
Additives give plastics specific desired properties, but over time these additives slowly release into the environment. Right now scientists know little about the long-term, cumulative effects of these additives. However, we do know of some that are already dangerous:
Bisphenol A (BPA) is used in the production of various types of plastic, but mostly for the tough and transparent plastic called polycarbonate. Excessive exposure to this substance harms fertility and an unborn child’s immune system. Not only can BPA enter the body through the mouth, but also through skin contact and inhalation.
Softeners are added to plastics like polyvinyl chloride (PVC) to make them more elastic. Over time, a proportion of these plasticizers leaches out and products lose that elasticity. In the environment, these chemicals from softeners do not break down chemically and accumulate in small organisms, eventually moving up the food chain and disrupting hormonal systems.
Fire retardants are added to prevent plastics from catching fire too easily. Since plastics are made from petroleum, they tend to burn easily. Fire retardants are added to almost all plastics.
Moreover, when plastics end up in the environment, they also bind to persistent organic toxins in the environment such as PCB and dioxins. These toxic substances then build up in the fats and tissues of marine animals in the food chain. The process by which an organism collects plastic over its lifetime is called bioaccumulation.
But not only are toxins collected in organisms, but the toxins are also passed down the food chain. This is called biomagnification.
Moreover, there is the threat of nanoplastics, plastics smaller than 0.0001 mm. Because nanoplastics are so small, they can easily enter tissues, organs, the brain, and individual cells.
Nanoplastics are proportionally far more toxic than larger plastics and can trigger local inflammation responses and all kinds of physiological effects.
Because they are so small they have a really large surface area compared to weight making them especially reactive. Nanoplastics bind to 100–1,000 times more toxins than microplastics.
Algae and zooplankton that are exposed to high concentrations of nanoplastics in laboratory conditions reproduce more slowly than normal and remain small. Mussels are more lethargic and grow more slowly.
Moreover, plastic pollution is forever changing our environment.
According to the UN, plastic pollution has emerged as the second most ominous threat to the global environment, after climate change.⁹
Microplastics have been found in the Arctic and Antarctic, on the tops of mountains, and in places where no one lives. Many microplastics in sizes such as 10 or 2 micrometers are impossible to be extracted from the environment.
So what should be done?
The plastic pollution problem as a whole is very complex. In order to solve it, we need multidisciplinary effort, the support of industries, and a lot of change. Right now many things are being done, but it’s still uncertain if our efforts will be fast enough.
One thing for sure is that plastic pollution needs to be addressed systematically. The way we deal with plastics has to be redesigned. Cleaning and recycling alone are not effective.
One idea is building a circular economy for plastics.
This is what today’s plastic economy flow looks like:
A ton of plastics are being produced and a minuscule amount is recycled and or ever used again as only 14% of plastic are collected for recycling, 14% are incinerated, 40% are deposited in landfills, and 32% leaked into the environment.⁷
The goal of building a circular economy is that the majority of plastics will be reused rather than thrown out.
Plastics are an example of technical materials, which are materials that cannot re-enter the environment safely, and to form a circular economy, the value of plastic has to be captured and recaptured endlessly. This can be done through reusing, sharing, redistributing, and recycling plastics.
What could we do?
In the United States, 2.5 million plastic bottles are thrown away every hour and on average a plastic bag is used for just 12 minutes.⁵
The average American produces around 85 kilograms of plastic waste each year.⁵
We as individuals are all responsible for contributing to this problem.
Single-use plastics make up a big part of the problem. More specifically, plastic packaging makes up 1/3 of all annual plastic waste.⁴
A first step would be for us to be more conscious consumers. We could do this by being more aware of the products we use and reducing our plastic footprint.
But this could be difficult and confusing. Like did you know that a single-use plastic bag produces far lower carbon dioxide emissions way requires way less energy to make compared to a reusable cotton bag? You would need to use your cotton bag 7,100 times before it would have a lower impact on the environment than the plastic bag.¹⁰
So here are a couple apps where you could learn more about plastic pollution:
- The Beat The Microbead app enables users to scan their own personal care items and determine whether they contain microplastics.
- My Little Plastic Footprint helps users understand how to reduce their plastic diets through actionable steps and quizzes.
But consumers’ role is still very limited. The best solution is just to go back to how we worked when plastics weren’t around, but plastics have so many properties that cannot be replicated within reasonable cost (water-resistance, non-permeability, lightness, durability, etc.). There is, though, various ways in which we could intervene and change the plastic system.
Interventions at the production stage will have to be complemented by interventions at other stages of the plastics life cycle, including in usage and disposal, where frontier technologies can play equally important roles. Two ways in which technology can help with the problem in the production phase is developing natural plastic substitutes, like genetically engineering plants, and developing biodegradable plastics. Two promising bio-based biodegradable polymers are polylactide (PLA) and Polylhydroxyalkanoates (PHAs), still much development is needed before they could replace traditional plastics.
Although plastic pollution is a difficult problem to solve, recent scientific advances provide hope.
At the University of Austin Texas, researchers have developed a new enzyme that could break down PET plastics using AI. This could make the plastic economy circular through depolymerization and repolymerization, breaking plastics chemically down into smaller parts and putting it back together.
Scientists at the University of Chicago are also researching how to create sustainable bioplastics using cellulose from the Miscanthus giganteus bamboo plant.
The field of materials informatics is leveraging big data and AI to speed up material discovery by reducing the number of experiments required during the materials development process by 50–70%.¹¹
This is done by first deciding the specifications for the new material. In the case of plastics, this could be thermal and mechanical properties like melting temperature and tensile strength, how resistant the material is to breaking under pressure. Then materials informatics, coupled with physics-based models, are used to propose potential candidates. Each candidates is then tested experimentally for viability using insights from machine learning, theory and simulation. Material informatics can help scientist find new candidates for bioplastics that are biodegradable.
The Global Plastic Watch (GPW) is using real-time satellite imagery and artificial intelligence to track plastic hotspots, locations of high plastic concentration. This could be territorial and sea-based. GPW can keep us accountable and measure what we are doing in terms of plastic pollution and monitor and identify regions where plastic pollution is a dire problem and breaking outdated or imperfect assumptions about the problem. The GPW can help quantify the problem and make informed action plans.
Although daunting to solve, with awareness, initiatives, and research, we can find our way out of plastic pollution.
Works Cited:
[1] Johns Hopkins University. “Ahoy, Friendly Floatees.” The Hub, HUB, 2 July 2021, https://hub.jhu.edu/magazine/2021/summer/rubber-duckies-ocean/.
[2] Pennington, James. “Every Minute, One Garbage Truck of Plastic Is Dumped into Our Oceans. This Has to Stop.” World Economic Forum, 27 Oct. 2016, www.weforum.org/agenda/2016/10/every-minute-one-garbage-truck-of-plastic-is-dumped-into-our-oceans/.
[3] admin. “Plastic Reef | Maarten Vanden Eynde.” Plasticreef.com, 2020, www.plasticreef.com/.
[4] Ritchie, Hannah, and Max Roser. “Plastic Pollution.” Our World in Data, Sept. 2018, ourworldindata.org/plastic-pollution.
[5] Abbing, Michiel Roscam. Plastic Soup: An Atlas of Ocean Pollution. Island Press, 2019.
[6] Vox. “Why 99% of Ocean Plastic Pollution Is ‘Missing.’” YouTube, 27 Apr. 2021, www.youtube.com/watch?v=fsjvwQclGLo.
[7] “Plastics and the Circular Economy.” Ellenmacarthurfoundation.org, 2016, archive.ellenmacarthurfoundation.org/explore/plastics-and-the-circular-economy.
[8] “The Circular Economy in Detail.” Ellenmacarthurfoundation.org, 2017, archive.ellenmacarthurfoundation.org/explore/the-circular-economy-in-detail.
[9] “Frontier Technology Quarterly: Frontier Technologies for Addressing Plastic Pollution | Department of Economic and Social Affairs.” Un.org, 2019, www.un.org/development/desa/dpad/publication/frontier-technology-quarterly-september-2019-frontier-technologies-for-addressing-plastic-pollution/.
[10] In. “Plastic Pollution: How Humans Are Turning the World into Plastic.” YouTube, 1 July 2018, www.youtube.com/watch?v=RS7IzU2VJIQ.
[11] Melia, Hannah R., et al. “Materials Informatics and Sustainability — the Case for Urgency.” Data-Centric Engineering, vol. 2, 2021, https://doi.org/10.1017/dce.2021.19.
[12] “Polymer Informatics: Opportunities and Challenges.” ACS Publications, 2017, pubs.acs.org/doi/full/10.1021/acsmacrolett.7b00228.
