I don’t know. Pm2.5 by definition doesn’t include gasses and as I understand it the issue is that the particulate matter, whatever it happens to be, gets in the bloodstream. Is there any particulate matter of that size that is not neurotoxic once it enters the bloodstream? I don’t know the answer but it seems like a legitimate question.
One would imagine that salt spray from the ocean (which can easily register as PM2.5) is mostly sodium chloride, is rather water-soluble, and is entirely harmless in your bloodstream in any quantity that you could plausibly inhale.
Pm2.5 is a specific particle size, yes, we do agree on that. Importantly, it is also a common measurement used in assessing air quality. In that context it is typically composed of particles from a set of common sources, like wildfires, industrial sources, automobile pollution, etc…. It is, in the context of air quality monitoring, never composed of amino acids. It seems valid to make claims about pm2.5 and health, even though the claim does not distinguish wildfire pm2.5 from pm2.5 from automobile pollution or other sources. Maybe I misunderstood you to be saying otherwise.
Yeah but which substances/sources is not given when you just say "Pm2.5". Which is what the article did. And depending on the actual substances you get different health effects or none at all.
