There is a lot of macroscale dumping of garbage - and the plastic stuff just accumulates over a time, until sunlight and wave action break it down. Howeve

There is a lot of macroscale dumping of garbage - and the plastic stuff just accumulates over a time, until sunlight and wave action break it down. However, a lot of this plastic _starts_ as micro-plastic particles: microbeads from cosmetics and polyester fibres from clothes (water from washing machines is full of this) - these are in household waste water and often end up in the ocean.