[throwaway657656]

"the average American brain sample with concentrations of 0.5 percent plastic by weight. That’s about the weight of a pencil in your brain. Think about that."

A related JAMA paper[0] suggests that the olfactory bulb may be the pathway to the brain via inhalation. I'm going to start rising my sinuses at night and in the morning as a precaution. A simple way is to put table salt in your palm and then water and inhaling the water from your palm. Not sure it will help and there are likely micro-plastics in the salt and water.

The good news is that in animal studies (I forget the source) the amount of plastic in the body levels off unless the amount of the plastic in the environment is raised. But I can't recall if also goes down in the body if environmental levels decrease.

[0]https://jamanetwork.com/journals/jamanetworkopen/fullarticle...

[dredmorbius]

Using tap water for nasal rinse puts you at risk for nasty bacterial infections, possibly affecting the brain.

Use distilled / dionised water, or boil water (and allow it to cool) for such use.

A neti pot or nasal rinse bottle are cheap at any druggist's.