Major Atmospheric Pollutants. V. Oxides of nitrogen
Combustion of fossil fuels containing nitrogen results in oxidation of nitrogen, producing a family of nitrogen oxides, Nox.
NO, at low concentrations, is harmless, but at high concentrations, will compete with oxygen to bind with hemoglobin.
NO2, nitrogen dioxide, is a reddish brown gas with a pungent, choking odor. It is a major component of photochemical smog.