Microplastics are fragments of plastic smaller than 5 millimeters, they can be specks of glitter, which are created at that size in the factory, or broken down pieces of larger plastics, like plastic bags or bottles, which often get torn to pieces by wind and waves in the ocean.
In a normal human habitat, microplastics are inescapable, especially in an urban one. They are in the water, the food, the clothing we wear (this is often a source of microplastics in fact), and even in the air that we breathe. Although they present only a very mild health risk, most people still aren’t comfortable having them around. When it comes to our oceans, however, the damage to their natural beauty is obvious, and the damage to marine life, though less obvious, can be a lot more dangerous than what it does to us.
Plastic in the ocean can kill animals who swallow it thinking it is prey, like a jellyfish. In microorganisms it can release a small amount of chemicals which may negatively affect the reproduction of those creatures, leading to an imbalance in the food chain. And larger chunks of plastic can often be found floating at the surface, looking very ugly and unsightly for most visitors. The country of the Philippines suffers from this problem the most, as one-third of all plastic ocean waste comes from the Philippines alone, meaning this area of the world has a lot to gain from seastead-oriented plastic cleanup. A seasteading community wouldn’t want to uglify its surroundings, so keeping plastic in the ocean to a minimum is desirable, but how do we do it?
Microplastics can be filtered out of the water by OTEC systems (discussed here) or strained out of the water when being pulled into a water desalination machine to produce independent fresh water for the community. While larger chunks of plastic can be netted using the method shown above and melted down alongside the microplastics to produce new, reusable goods for sale inside the seasteading city, or available for export to nearby communities. Once we are in a position to capture and refine these materials, the possibilities are endless, and the profit to be made in restoring the ecosystem becomes immediately apparent.