Comparing Metro Phoenix
Nitrogen Dioxide
Description: Nitrogen Dioxide (NO2) is one of the criteria air pollutants identified by the EPA as being critical to assessing the environmental health of a place. The primary source of NO2 is emissions from vehicles and electric power generation as a product of the combustion process. This is also a contributing pollutant in the formation of ozone. When nitrous oxides react with volatile organic compounds, also present in the atmosphere, ozone is produced.
Rationale: NO2 is a lung irritant and can lower a person’s resistance to lung infections such as bronchitis, influenza and pneumonia. It is also a contributing pollutant to the formation of smog and to acid rain, reducing visibility in urban settings and open spaces. Annual mean concentration levels are identified in the graphs. The National Standard for this criteria pollutant is 0.053 parts per million (ppm). None of the comparator cities shows a recorded annual mean that exceeds this standard during the timeframe presented (1996 - 2006). No Metropolitan Statistical Areas in the US are in non-attainment for NO2. Previously, only the Los Angeles region held this designation. However, monitoring is necessary throughout the US due to the relationship between nitrous oxides and ozone, smog and other health effects.
Source: Decision Center for a Desert City (DCDC) using records from the U.S. Environmental Protection Agency's Monitor Trends Report - Criteria Air Pollutants.
