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Nitrogen Oxides (NOx)

Red Haze Harry (Pollutant: Nitrogen Oxides) Air Villain

Nitrogen Oxides (NOx)

Air Villain: Red Haze Harry

Status: Busted

Description: (Compound) NOx is the generic term for a group of highly reactive gases containing nitrogen and oxygen. Many NOx are colorless and odorless, but nitrogen dioxide (NO2) can combine with particles in the air to form a reddish-brown haze over urban areas.

Crime: NOx can cause respiratory problems.

Cause: NOx comes from the reaction of nitrogen and oxygen during the burning of coal, oil and gas. Motor vehicles and power plants are large sources of NOx. NOx are important ingredients in ground-level ozone or smog, particulate matter and precursors to the formation of acid rain.