How plastic behaves in the ocean

Plastic is a relatively new material in the grand scheme of things. Even though the first petroleum derived plastic was made in 1907, we only started to mass-produce it around the 1950's.

There are 2 general types of plastics; the ones derived from petroleum, and the ones derived from plant matter. Sourcing the latter might be a bit more environmentally friendly, but both outcomes are the same: plastic, a man made material that does not biodegrade.

Note: Some “plastics” like PLA or Nylon, can biodegrade because not only are they sourced from plant matter, but the end result of processing them is a “long chain of sugar molecules fused together”, rather than chains of polymer.

Note: Biodegrading means that a material can be broken down back into organic matter by micro-oragnisms. Plastic, on the other hand, photo-degrades, meaning it breaks down into smaller (still plastic) pieces when exposed to heat and sunlight.

This means that every single piece of plastic ever made is still somewhere, in one form or another, on the planet; all 8.3 billion metric tons of it manufactured since the 1950s. But why should we care at all that plastic ends up in the ocean? It’s simple enough: plastic in the ocean kills animals, and poisons us humans being, too.

How plastic behaves before it degrades

Blown by the wind or fallen into a sewer, plastic debris finds its way through rivers and lakes, to the ocean. There are 10 million tons of plastic being dumped in our oceans every year, and the result is lethal for sea life.

For a sea turtle, a plastic bag looks just like a delicious jelly fish, but the creature does not know how risky this meal is. When animals eat plastic, it can get caught in their throat, causing them to choke to death. But when they actually manage to swallow the stuff (and they do so very often), it remains in their stomach for ever, eventually taking up all the space, and starving them to death. Another way plastic can be fatal to sea life is if they get caught in it; rendered unable to swim freely, they die of exhaustion trying to free themselves.

How plastic behaves after it degrades

As noted above, plastic photo-degrades instead of bio-degrading. Sunlight and warmth breaks the polymer chains into smaller, weaker ones, eventually shredding it into micro-particles. That is particularly true for plastic bags, them already being thin and more fragile.

Most plastics release toxins when degrading, but even those that don’t become a problem once broken down in the ocean. The micro-particles resulting from photo-degradation attract other pollutants, like chemical pesticides, petroleum oil, and industrial chemical run-offs. These little toxic sponges are then eaten by fish, and are so small they pass through their stomach wall and into their flesh, which eventually gets eaten by us, humans. These micro-particles of plastic also make their way into the human digestive system is through our water filtration systems. They are indeed small enough to go through water filters, and humans find themselves unknowingly drinking them, either in tap, filtered, or even bottled water.

Note: This article explains how micro-particles of plastic are now found in the sea salt we use to season our food.

The problem with plastic ending up on our dinner plate is simple: just like the micro-particles find their way into the flesh of fish, they find their way into ours, too. Plastic particles then accumulate in our body tissues, where they act as endocrine disruptors.

Note: The endocrine system produces hormones responsible for growth, sexual development, and metabolism.

Plastic is in our water. Plastic is in our food. Plastic is inside us.

What now?

Plastic in the ocean kills animals and poisons us. But we can help change that.

The plastic that is already in the food chain will most likely remain there. But there are so many solutions to reduce, and eventually bring to zero, the amount of the stuff we dump in the ocean every year.

On a personal basis, we can refuse as much of it as we can.

On a collective basis, we can encourage new, better habits.

On a global basis, we can stay informed, and educate.

Sources

PLA and Nylon: http://www.bbc.com/news/magazine-27442625

Toxicity in plastics: http://www.independent.co.uk/environment/plastic-microplastic-microbeads-pollution-toxic-environment-house-of-commons-environmental-audit-a7011256.html

Micro-particles in sea salt: https://www.theguardian.com/environment/2017/sep/08/sea-salt-around-world-contaminated-by-plastic-studies?CMP=share_btn_tw