OCEAN PLASTICOSIS
The quiet force exacerbating the climate crisis
—Thailand 2023—
The introduction and integration of plastic debris into marine and coastal ecosystems is creeping up to further exacerbate the climate crisis. It is a frontier of scientific understanding.
Plastic debris is a prevalent problem across the globe from the terrestrial to the oceanic environment. Many of us have heard about how plastic is causing plasticosis impacts on animals of all sizes—from big whales to fishes, bivalves, as well as tiny zooplankton [1]. However, as the ocean contributes greatly to the carbon sink processes [2], the frontier of marine science is beginning to learn more about how the plastic cycle may also impact the carbon cycle [1, 3]. In other words, we are at the cusp of understanding how plastics interfere with natural carbon capture, transferal, and sequestration mechanisms.
What we already know is that greenhouse gas (GHG) is emitted at every stage of the plastic cycle from its production processes all the way to its breakdown and decomposition processes [4-6]. New studies also find that major photosynthesizing organisms of the world (phytoplankton) are also affected by plastic leachate exposure [7-9]. Although phytoplankton still largely outnumber microplastic, a significant climate crisis contribution is not unimaginable if plastic usage and waste mismanagement trends continue.
Frontier of Science
Scientists estimate that roughly 50% of the oxygen production on Earth comes from the ocean—the phytoplankton.[10, 11] Through photosynthesis, phytoplankton is the main contributor to capture carbon from the atmosphere. As plastics can impact marine prokaryotes, the overall ocean’s contribution to carbon capturing may also be disrupted.[1, 3]
Synechococcus and Prochlorococcus are photosynthesizing bacteria in the ocean that contributes to about 20% of global photosynthesis[12], which is a fundamental part of the carbon cycle. Marine scientists globally are figuring out the relationship between the plastic cycle and the carbon cycle.
Facts and Figures
Of the 9,200 million tons of global cumulative production of plastic between 1950-2017, around 58% of which have been discarded into landfills, dumps, or uncontrolled waste. The rest of the produced plastics are either still in use in the original form, in the recycled form, or have been incinerated.[13] These numbers are expected to triple by 2040 without meaningful interventions.[1]
Asia is contributing to 81% of global plastic emission to the ocean, and Thailand alone is contributing 2.33% (22,806 tons) in 2019.[14] While Thailand’s plastic waste generation is about 3.5 million tons, 10 times less than that of the US, the mismanaged plastic waste being emitted to the ocean is 10 times higher in Thailand than the US.[15] These amounts are also rising annually.
Acknowledgment
NOOR Foundation’s "Visualising the Climate Crisis” mentoring program in Southeast Asia for the mentorship and support for me to realize this project.
Aow Thai Marine Ecology Center (ATMEC) for continuous support for my learning on marine science.
Marine Ecology Laboratory at Chulalongkorn University, Department of Marine Science, for allowing me to photograph microscopic images in your labs.
Biological Oceanography Laboratory at Prince of Songkla University (Phuket Campus), Faculty of Technology and Environment, for your input on underwater microbiome research.
References
UNEP, From Pollution to Solution: A global assessment of marine litter and plastic pollution. 2021, UNEP: Nairobi.
Riebeek, H. The Ocean's Carbon Balance. 2008; Available from: https://earthobservatory.nasa.gov/features/OceanCarbon.
Zhu, X., The Plastic Cycle – An Unknown Branch of the Carbon Cycle. Frontiers in Marine Science, 2021. 7.
Bauman, B. How plastics contribute to climate change. 2019; Available from: https://yaleclimateconnections.org/2019/08/how-plastics-contribute-to-climate-change/.
OECD. Plastic leakage and greenhouse gas emissions are increasing. n.d.; Available from: https://www.oecd.org/environment/plastics/increased-plastic-leakage-and-greenhouse-gas-emissions.htm.
CIEL, Plastic & Climate: The Hidden Costs of a Plastic Planet. 2019, Center for International Environmental Law.
Tetu, S.G., I. Sarker, and L.R. Moore, How will marine plastic pollution affect bacterial primary producers? Communications Biology, 2019. 3(55).
Tetu, S.G., et al., Plastic leachates impair growth and oxygen production in Prochlorococcus, the ocean’s most abundant photosynthetic bacteria. Communications Biology, 2019. 2(184).
Focardi, A., et al., Plastic leachates impair picophytoplankton and dramatically reshape the marine microbiome. Microbiome, 2022. 10(179).
National Ocean Service, N. How much oxygen comes from the ocean? n.d.; Available from: https://oceanservice.noaa.gov/facts/ocean-oxygen.html.
Morsink, K. With Every Breath You Take, Thank the Ocean. 2017; Available from: https://ocean.si.edu/ocean-life/plankton/every-breath-you-take-thank-ocean.
Pennisi, E. Meet the obscure microbe that influences climate, ocean ecosystems, and perhaps even evolution. 2017; Available from: https://www.science.org/content/article/meet-obscure-microbe-influences-climate-ocean-ecosystems-and-perhaps-even-evolution.
Geyer, R., Jenna R. Jambeck, and K.L. Law, Production, use, and fate of all plastics ever made. Science Advances, 2017. 3(7): p. e170078.
Meijer, L.J.J., et al., More than 1000 rivers account for 80% of global riverine plastic emissions into the ocean. Science Advances, 2021. 7(18): p. eaaz5803.
Jambeck, J.R., et al., Plastic waste inputs from land into the ocean. Science, 2015. 347(6223): p. 768-771.