Due to the
current air quality in the Twin Cities here I'm resurrecting a not-long-dead thread.
Originally Posted by John C. Ratliff
Diesel exhaust particles are very small; they don't settle out. Instead, they stay with the air flow, and penetrate very deep into the lungs, actually into the alveoli themselves (air sacs). They are less than a micron in diameter (0.5 microns = 1.96850394 x 10-05 inches = 0.00002 inches). This means they are deposited deep in the lungs, and a significant number end up in the air sacs themselves. They cannot settle because the motion of the molecules in the air keeps them suspended (Brownian motion). But they go to the places the molecules go. They deposite deep in the lung, and can diffuse into the cells in the air sacs. Breathing through the nose does not significantly affect this deposition. Here's a
PubMed Reference Article
Re-reading this reminds me of something from my aquarium-keeping days. I had a nasty bout with suspended algae and what finally got rid of it was something that made the algae stick together so that it became large enough to be taken out by the filter. Seems like there could be some lung maintenance product that does the same thing with small particulates in the lungs - react with them in some way so they become large enough to be trapped in the mucous and removed by the cilia. Is there such a thing?
Nathan