Specifically: Leaded gasoline (with tetraethyllead), nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), unburned hydrocarbons.
https://en.wikipedia.org/wiki/Tetraethyllead , https://en.wikipedia.org/wiki/Sulfur_oxide , https://en.wikipedia.org/wiki/NOx
Specifically: Leaded gasoline (with tetraethyllead), nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), unburned hydrocarbons.
https://en.wikipedia.org/wiki/Tetraethyllead , https://en.wikipedia.org/wiki/Sulfur_oxide , https://en.wikipedia.org/wiki/NOx