4 ms·

PM2.5 particles are thing that give you cancer and higher concentrations are related to car traffic. PM10 are not healthy either.

• hollerith 9y ago
  Oh, sure, but again the CO, NOx, SOx and most of the unburnt hydrocarbons in gasoline-fueled vehicle exhaust are not particles (they're gasses) and are not removed to any significant degree by a HEPA filter. In the US, diesel cars are rare, and I would guess that the non-diesel cars in the US produce very little in the way of particulate pollution. Am I wrong about that?
  • llukas 9y ago
    Hmm. According to this https://www.epa.gov/sites/production/files/2015-09/documents/sbai_pres.pdf https://www.epa.gov/sites/production/files/2015-09/documents... Most particulates are from exhaust but amount of this is falling and soon most contributing factor would be brake/tire wear.
    • hollerith 9y ago
      That's why I used the qualifier "gasoline-fueled": the particulates are coming mostly from _diesel_ engines. (I didn't belabor that point earlier because I assumed that people here would already know that because the VW diesel-emissions cheating scandal was such a big story.) During a busy commute in a major US metro area, the vast majority of the vehicles on the road are gas-powered (because a large fraction of trucks will avoid busy commutes). I realize the situation is different in Europe where diesel-powered cars are much more common.