In a previous post, I wrote about the innumerable flip flops polluting the ocean. But a question that kept coming up in my mind was, why even is there trash floating around the ocean? Why is there so much of it? Where does it all come from and who is responsible for it?

First, the copious amount of marine debris found in the ocean can be attributed to the long decomposition time of non-biodegradable waste.  For example, the International Union for Conservation of Nature writes that “plastic makes up 80% of all marine debris found from surface waters to deep-sea sediments”, and various sources estimate that 8-14 million tons of plastic are dumped in the ocean annually. This means that a vast majority of waste persists in the ocean long after it is discarded by its user(s).

How long waste takes to decompose at sea. (Source: Health, Food Chain Safety and Environment Belgium)

So, where do these heaps of trash polluting the ocean come from?

  1. Individuals littering at the beach, on boats or even further inland. This source has long been my understanding of why there is trash in the ocean. Going to East Coast beach seemed to prove my assumption; there are often food wrappers, leftover food from picnics, beer cans, plastic bottles, cigarettes etc. on the sand. These are obvious sources since it is very direct—from human hands to the sea. Laziness and having an ‘out of sight, out of mind’ attitude which leads to intentional littering is definitely a problem. Additionally, litter from inland can be carried by the wind, or by rivers and streams leading to drains which then empty into the sea. Think of the cigarettes floating in the river or plastic bags flying in wind, for example.
  2. Ocean-based sources, like the fishing or shipping industries and offshore platforms. These sources may contribute to marine debris via illegal dumping of waste or by accidentally losing fishing equipment, cargo, etc.
  3. Inland sources of mismanaged waste. In reality, 80% of marine debris is leaked from inland and an estimated 2 billion people “do not have access to organized waste collection services”. A large proportion of marine debris reportedly comes from poorly managed sources in rapidly developing countries like China, the Philippines, Indonesia and Vietnam. Furthermore, trash from overfilled dumping grounds often ends up in surrounding waterways and drainage systems, such as in Mumbai’s infamous Deonar dumping ground. That said, even sophisticated waste systems have leaks in them. As previously explained, the wind and waterways may carry stray trash into the ocean unintentionally as well.

The key idea here is that pollution is transboundary. Our inland pollution has ramifications for the ocean and marine ecosystems.

In hindsight, the fact that marine debris is largely a result of leakages in waste systems is no surprise. While I am uncertain about what could possibly be done to address this systemic issue, I now understand that responsibility should not be put solely on individual consumers to not litter. Rather, waste companies and policymakers should look with urgency into reducing waste leaks as much as possible in order to address the horrifying volumes of trash polluting the ocean.

 

 

References:

https://www.health.belgium.be/en/waste-how-long-decompose-sea

https://www.iucn.org/resources/issues-briefs/marine-plastic-pollution

https://www.nationalgeographic.org/article/heres-where-oceans-trash-comes/

oceanconservancy.org/trash-free-seas/plastics-in-the-ocean/trash-free-seas-alliance/

https://www.worldbank.org/en/news/feature/2018/06/08/planet-over-plastic-addressing-east-asias-growing-environmental-crisis

Pattiaratchi, C., Mirjam van der Mheen, Schlundt, C., Narayanaswamy, B. E., Sura, A., Hajbane, S., . . . Wijeratne, S. (2022). Plastics in the Indian Ocean – sources, transport, distribution, and impacts. Ocean Science, 18(1), 1-28. doi:http://dx.doi.org.libproxy1.nus.edu.sg/10.5194/os-18-1-2022