Comment by stephen_g
While I’m quite concerned about particulates generally (I use a few HEPA air purifiers around the house etc.), with this kind of thing it does feel like that kind of matter can’t be as bad for you as other types of PM2.5. I haven’t yet seen any research quantifying it (most studies just look at all PM2.5 as a single category) but surely there must be a difference about how bad different types of particulates are depending on what they’re made of - like those from combustion, tyre wear etc. it would seem are very obviously going to be toxic, but I also measure raised PM2.5 from cooking with my electric oven or induction stove (but not burning the food), surely that can’t be quite as bad? And sea spray you would think would be even less harmful…
Most definitely different types of particles cause different levels of harm. (Extreme example: asbestos.) However, we don't really have good data to quantify this. It intuitive from evolutionary perspective that "natural" sources would be less harmful since we've been breathing sea spray and dust for millions of years. Yet, smoke from wood fires is clearly still extremely harmful. So... my instinct is that the harm is probably less, but I find it very hard to be confident that any particular source is totally safe.