Reviewing: Peng, Y., Wu, P., Schartup, A. T., & Zhang, Y. (2021). Plastic waste release caused by COVID-19 and its fate in the global ocean. Proceedings of the National Academy of Sciences, 118(47).
Plastic is an indispensable part of our lives during the COVID-19 pandemic. Plastic products have protected every member of our society: disposable face masks and gloves that we wear, medical suits and surgical masks that protect the frontline healthcare workers, single-use medical equipment that saves patient’s lives, and packaging that comes with online shopping and grocery deliveries that help us keep our physical distance from others. But are you aware of how much plastic is being used globally to fight the pandemic? And how much of that is making its way into the ocean? And how long it will stay in the ocean?
A team of scientists calculated that we have created 8.4 million tons of plastic waste since the beginning of the pandemic. That is equivalent to the weight of ten Golden Gate Bridges! Nearly 90% of this waste comes from plastic packaging and products used in hospitals, while about 7% comes from public use of face masks. And 26,000 tons of plastic waste (as heavy as the Statue of Liberty) has already made its way to the ocean. Plastic waste gets carried all the way to the ocean by rivers, and rivers that have high population density near the river mouth, experience high levels of runoff, or are fast flowing, can transport more plastic than others. Examples of these rivers are the Yangtze River and the Indus River, which were estimated to put 4,000 tons of plastic waste each into the ocean during the pandemic.
To estimate where plastic waste that entered the ocean will end up in the next several decades, the scientists built an ocean plastic model that takes possible fates for a piece of plastic floating on the surface ocean into account – such as drifting with the current until it reaches a beach, falling and settling down on the seafloor, or wearing out over time and breaking into small fragments. By the end of this year, most plastic would not have had enough time to travel far from land, and will get onto beaches or seafloor that are close to the rivers that initially transported them into the ocean. This means that coastal areas are most jeopardized for immediate environmental impacts of plastic waste, such as injuries and death of marine organisms.
However, as plastic continues traveling with the ocean currents, it will reach the open ocean (ocean that is far from land) by 2025. Ocean water continuously flows over thousands of miles, following a specific pattern called the thermohaline circulation. The word “thermohaline” is a combination of “thermo“ (heat) and “haline” (salty), and small differences in seawater temperature and saltiness determine how heavy a volume of seawater is, causing seawater to move. Generally, surface water at the Arctic Ocean and the high latitude North Atlantic sinks to the bottom of the ocean, moves the deep water southward all the way to the Antarctic Ocean, then moves into to the Indian and Pacific Ocean, rises to the surface and again reaches the North Atlantic to sink again. Because the sinking of surface waters happens in the Arctic and the high latitude North Atlantic, about a fifth of plastic waste on the seafloor will be accumulated in these areas by 2100. We may also find more plastic garbage patches in parts of the North Pacific and Indian Ocean, similar to the “Great Pacific Garbage Patch” that has been around for a couple of decades.
Is there anything we can do to reduce plastic waste in our everyday lives? A good starting point is to be aware of how much harm plastic can cause to the environment unless it is better recycled and managed. While governments, policymakers, businesses, researchers and the public will all need to work together to better manage and treat plastic waste, we can try to make small changes in our lifestyle to begin with. You may be able to teach yourself, your family and friends about your responsibility to appropriately recycle or dispose plastic waste. You may be able to skip online shopping, shop at your local farmer’s market and bring reusable bags. You may be able to participate in community events and contact the legislators in your area to reduce single-use plastic. Your small actions today will help protect our oceans from plastic pollution!
I am a PhD student in chemical oceanography at University of Washington. I am studying how different forms of metals in the ocean are shaping microbial communities in the North Pacific Ocean. When not working, I like going for a walk, visiting farmers’ markets and playing keyboard.