Air Pollution the Atmosphere Types of Pollutants Photochemical Smog

The Atmosphere Types of Pollutants

• Mostly Nitrogen and Oxygen Air Pollution • Troposphere – lower 17 km • Stratosphere – 17 to 48 km

Photochemical Smog – Secondary Pollutant Complex Chemistry of Smog

• Primary Pollutants – right out of the stack or • Nitrogen oxides and tailpipe volatile organics in UV radiation • Secondary Pollutants – Created in the • Brown haze Atmosphere • Best produced on bright, sunny days in hot climates – St. Louis in summer

What is Smog? St. Louis Problem

• Nitrogen oxides from cars • Ozone • Ozone – Produced from nitrogen in air when it comes • PAN’s – peroxyacyl nitrates – We are out of into contact with hot engine parts compliance with •Aldehydes federal law • This is why your car has a catalytic converter • All Nasty stuff – Vehicle Inspection • Volatile Organics – VOC’s •Illinois – Irritates lungs – Escaped gasoline – Brown Haze • This is why gas stations have the special nozzles in Missouri Inspection Station St. Louis

1 Temperature Inversions • Air cool at surface – warm higher up What, me worry? – Seals off air around the city – Really bad in valleys • Chronic bronchitis • 1949 Donora, Pa. Air Pollution disaster • Bronchial asthma – 20 deaths • Emphysema – 14,000 illnesses • Particular problem for young and old • Los Angeles – local topography encourages • Problem of smog epidemiology – Exposure not limited to one chemical

• Nitric and sulfuric acids – Secondary pollutants • Sources Acid Deposition – Fossil fuels • Illinois Coal – Smelting of sulfide ores

Impacts of Acid Deposition

• Acidifies lakes downwind – Destroys fisheries • Kills high altitude forests • In extreme form can completely destroy landscape – Nickel smelters in Sudbury, Ontario

2 Clean Coal Burning Stack Scrubbers

Reduction of Criteria Pollutants Clean Air Acts 1970, 1977, 1990 in US between 1970 and 1998 • Establish 6 “criteria pollutants” • Carbon Monoxide (CO) – 60% • National Ambient Air Quality Standards for • Nitrogen Dioxide (NO ) – 2% criteria pollutants 2 – Margin of safety for people who are most sensitive • Sulfur Dioxide (SO2) – 58% • Allow emissions permits • Suspended Particulates – 25% – Secondary market • 1990 act required coal burning plants to cut sulfur • Ozone (O3) – 30% emissions by ½ by 2000 • Lead (Pb) – 97% – Clean coal technology or low sulfur coal