Personal anecdote; just got back from a trip to Hawaii. Many of the beaches there had significant deposits of pebble sized and smaller visible plastic particles. Presumably there’s exponentially more smaller ones that I couldn’t as easily see. Some of the beaches had plastic floating in the water. Locals said it wasn’t island dumped garbage, it was brought in from currents from the ocean. Horrific to see.
It seemed very much dependent on currents, as beaches further south on the windward shore were still pristine.