Given the wide variety of chemicals lumped under the name "microplastics" and the complexity of the systems of the human body, many of which even modern medical

Given the wide variety of chemicals lumped under the name "microplastics" and the complexity of the systems of the human body, many of which even modern medical science doesn't fully comprehend, the chance that they're all or even mostly inert is extremely small. Also "inert" materials can cause problems in human body all the time, even if it's just simple inflammation from the immune system responding to the physical damage they can cause. It's like continuously pouring small grains of random dirt you scraped off the ground into your car's engine while it's running, when you're not entirely sure how the engine works, and going "meh, they're just tiny particles of dirt. My engine is still running. Probably fine". You can run that experiment on your one and only body if you wish.