Secondary pollutants in LA smog:

  • O3 - ozone
  • NO2 - nitrogen dioxide
  • particles
  • PAN - peroxyacetyl nitrate
  • 'These are products of reactions in the atmosphere. There are NOT directly emitted.
  • The main secondary pollutant is ozone....... near the surface, it is bad for us, but up in the stratosphere, it's a good thing....

South Coast AQMD web site: