1. OZONE ATMOSPHERIC POLLUTION Ozone in urban smog J (Hans) van Leeuwen

3. Ozone in the atmosphere  Ozone: stratospheric good; tropospheric bad  Ground-level ozone resulting from NO x +VOC +sunlight  Statospheric ozone is formed naturally and screens out harmful UV  Ozone pollution is a regional problem as it travels 100s of miles

5. Ozone production from NO x

7. Photochemical smog reactions N 2 + O 2  2NO 2NO + O 2  2NO 2 NO 2 + h  NO + O O + O 2 + M  O 3 + M O 3 + NO  NO 2 + O 2 These reactions are cyclical with little net O 3 Hydrocarbons and water can remove NO

8. Oxygen atoms freed from nitrogen dioxide by the action of sunlight attack oxygen molecules to make ozone. Nitrogen oxide can combine with ozone to reform nitrogen dioxide, and the cycle repeats. Ozone production from NO x

9. Free radical reactions in air O + H 2 O  2OH. RH + OH.  R. + H 2 O R. + O 2  RO 2. RO 2. + NO  RO. + NO 2 RO. + O 2  HO 2. + R ’ CHO HO 2. + NO  NO 2 + OH. Build-up of NO 2, O 3 and aldehydes results - also PAN – peroxyacetyl nitrate

10. Free radical pathways to O 3

11. Diurnal variations in NO x and O 3

12. LA smog

13. Hourly Air Quality Report http://www.airnow.gov/

14. Key NOx control for coal boilers

15. NOx control on cement plants

16. http://www.sonomatech.com/smogcity/ Use this to see the effects of weather And human activities on ozone levels

17. This photo shows a healthy lung air way and an inflamed lung air way. Ozone can inflame the lung's lining, and repeated episodes of inflammation may cause permanent changes in the lung. Ozone damage to lungs

18. Ozone damage to plants

19. Ozone Concentration (ppm) Air Quality Air Quality (8-hour average, unless noted) Index Values Descriptor 0.0 to 0.064 0 to 50 Good 0.065 to 0.08451 to 100 Moderate 0.085 to 0.104101 to 150 Unhealthy (sensitive groups) 0.105 to 0.124151 to 200 Unhealthy 0.125 (8-hr.) to 0.404 (1-hr.)201 to 300Very Unhealthy

20. This map shows ozone levels in the eastern United States on August 24, 1998

21. http://www.epa.gov/cgi-bin/airnow.cgi?MapDate

22. 80-99ppb 61-79ppb 100-110ppb

23. 125+ O 3

26. http://www.epa.gov/airnow

27. Ozone levels today http://airnow.gov/

28. EPA Air Quality Index Levels of Health Concern Ozone: Air Quality Conditions 0 to 50GoodThe air quality for your community is considered satisfactory and air pollution poses little or no risk. 51 to 100ModerateAir quality is acceptable; however, people who are unusually sensitive to ozone may experience respiratory symptoms. 101 to 150Unhealthy for Sensitive Groups Children and adults who are active outdoors and people with respiratory disease are at greater risk from exposure to ozone. When values are between this range members of sensitive groups may experience health effects. The general public is not likely to be affected when ozone levels are in this range. 151 to 200UnhealthyEveryone may begin to experience health effects. Members of sensitive groups may experience more serious health effects. 201 to 300Very UnhealthyOzone levels between 201 and 300 trigger a health alert, meaning everyone may experience more serious health effects. 301 to 500HazardousOzone values over 300 trigger health warnings of emergency conditions. The entire population is more likely to be affected. Hazardous ozone values are extremely rare in the U.S.