Top 10 Dirtiest U.S. Cities
More stringent regulations and clean air initiatives have helped with the air quality problem the United States faces, but over 175 million people in the U.S.—roughly 58 percent—still suffer from pollution levels that are often dangerous, according to the American Lung Association.
The most common kinds of air pollution fall into two categories: ozone (smog) and particle pollution (soot). Breathing either does not do a body good. Air pollution is a serious health threat that affects all exposed to it. It can lead to large variety of lung ailments and can have a severe impact on cardiovascular health–it speeds up aging and it can be deadly. Some of the biggest sources of air pollution are dirty power plants, old diesel vehicles and heavy equipment, and ocean-going vessels.
Ozone (O3) is a highly reactive gas molecule composed of three oxygen atoms. Although in the upper atmosphere ozone is essential (it protects us from much of the sun’s ultraviolet radiation, thank you ozone)–ozone air pollution at our level is harmful and causes serious health problems by attacking lung tissue and causing inflammation and other damage.
In the America Lung Association State of the Air Report 2010, American cities were ranked according to ozone levels, as well as short-term and year round particle pollution levels. The cities are ranked by the air quality in the most polluted county in the metropolitan area. Here are the ten cities with the highest levels of ozone, number 1 being the worst–with any other rankings they scored for particle pollution.
1o. Charlotte-Gastonia-Salisbury, NC-SC
9. San Luis Obispo-Paso Robles, CA
8. San Diego-Carlsbad-San Marcos, CA
Ranked 17th for short-term particle pollution.
7. Houston-Baytown-Huntsville, TX
Ranked 16th for year round particle pollution.
Ozone is in the atmosphere from raw gases that come out of tailpipes, smokestacks and many other sources. These essential raw ingredients for ozone are nitrogen oxides (NOx) and hydrocarbons, also called volatile organic compounds (VOCs). They are produced primarily when fossil fuels like gasoline, oil or coal are burned or when some chemicals, like solvents, evaporate.
6. Hanford-Corcoran, CA
Ranked 8th for year round particle pollution and 10th for short-term particle pollution.
5. Sacramento-Arden-Arcade-Yuba City, CA-NV
Ranked 6th for short-term particle pollution.
4. Fresno-Madera, CA
Ranked 6th for year round particle pollution and 2nd for short-term particle pollution.
3. Visalia-Porterville, CA
Ranked 3rd for year round particle pollution and 8th for short-term particle pollution.
2. Bakersfield, CA
Ranked 2nd for year round particle pollution and 1st for short-term particle pollution.
1. Los Angeles-Long Beach-Riverside, CA
Ranked 4th for year round particle pollution and 3rd for short-term particle pollution.
Since ozone is a secondary pollutant (not formed directly by the burning of fossil fuels, but from nitrogen oxides produced by such combustion, and that then react in the presence of sunlight) it is the biggest problem in areas that are sunny and hot. In addition, LA is a low basin surrounded by mountains, with an enormous amount of automobile traffic.
Here are just a few steps you can take to improve air quality: