Particulate matter is composed of several substances. The largest portion consists of soil or dust that becomes airborne due to vehicles, wind, construction or agricultural activities. Ammonium nitrate and ammonium sulfate are extremely fine particles that result from chemical reactions in the air. These particles are made up of ammonia from livestock operations and oxides of nitrogen and sulfur from burning of fossil fuels. Nitrogen Oxides Nitrogen dioxide is a corrosive gas that appears yellowish or brownish depending on the concentration.
Nitrogen dioxide can cause respiratory illness and increase breathing difficulty.
When NO X combines with volatile organic compounds and warm temperatures, it is part of the chemical reaction that produces ozone. Mixed with moisture in the atmosphere, NO X can create acid rain, which can harm humans, animals and vegetation, as well as erode buildings. United with ammonia in cold moist conditions, NO X forms secondary particles that fit the PM 2.5 category. Secondary particles from nitrogen oxides are a significant portion of particulate matter pollution in the Treasure Valley on days with stagnant weather. Nitrogen oxides form when fossil fuels are burned at high temperatures in motor vehicles, trains, airplanes, power plants, heating devices, and industrial activities.