Chapter 6: AIR “I thought I saw a Blue Jay this morning. But the smog was so bad that it turned out to be a cardinal holding its breath.” Michael Cohen

Clean Air = 78 % Nitrogen and _21__% Oxygen Air Pollution – When harmful substances end up in the air at unhealthy levels. Pollution can be in solid, liquid or gas form. Most air pollution is a direct result of human activities. Natural Sources of air pollution – volcanoes dust pollen spores

Primary Pollutant – a pollutant that is put directly in the air by humans Secondary Pollutant – these are formed when primary pollutants come in contact with other primary pollutants, or natural substances, and a chemical reaction takes place. Example: Ozone Air pollution has been a recorded problem since Roman times.

POLLUTION ON WHEELS Over one third of our air pollution comes from the burning of gasoline to run motor vehicles. In 1995 American vehicles traveled an estimated 2 TRILLION miles

The Clean Air Act of 1970 and updated in 1990 gives the Environmental Protection Agency the power to regulate automobile emissions. The required reduction of lead in gasoline lowered the lead pollution in the atmosphere by 78%. If people car pooled with one other person 33 million lbs less Carbon Dioxide would be released into the air. Another option to reduce pollution are alternative fuels, such as ethanol. Burning ethanol produces water and CO2

INDUSTRIAL AIR POLLITION Electric power plants Electric power plants create more pollution than any other single source. 2/3 of all sulfur dioxide 1/3 of all nitrogen oxides 1/3 of all particulate matter The Clean Air Act requires many industries to: Use scrubbers in their smoke stacks Use electrostatic precipitators to remove particulates

THERMAL INVERSIONS Air circulation in the Atmosphere usually keeps pollution at the surface at non dangerous levels Air circulation in the Atmosphere usually keeps pollution at the surface at non dangerous levels. A Thermal Inversion is when warmer air sits on top of cooler air holding it and its’ pollution near the surface. * This often occurs in valleysSMOG Is when air pollution hangs over urban areas and reduces visibility. SMOG = SMOKE + FOG Results from chemical reactions involving sunlight, nitrogen oxides, and hydrocarbons.

EFFECTS ON HUMAN HEALTH Those who are very old and very young are most susceptible to the effects of air pollution. Conditions caused/ aggravated by pollution: Chronic bronchitis and bronchial asthma persistent inflammation of the bronchial tubes and becoming blocked with mucus Emphysema when the air sacs of the lungs lose their elasticity, decreasing the ability to exchange O2 and CO2. Lung cancer besides smoking, exhaust and particulates are to blame.

Sick building syndrome Sick building syndrome – buildings sealed up too well, lack of exchange of inside and outside air. Radon Gas Radon Gas – dangerous because it releases alpha particles when decaying which damage genetic material in cells of air passages Asbestos Asbestos – name given to several fibers containing silica that are strong and resistant to heat, but are hazardous when inhaled. Indoor Air pollution a problem because Americans spend almost 89% of their time indoors

Other types of Pollution  Noise pollution: irritating and damages ears  Hearing loss in the US has doubled in the last 30 years.  Light pollution: not hazardous, but has negative effect on environment.

ACID PRECIPITATION ACID PRECIPITATION (aka acid rain) results from the burning of fossil fuels. Oxides of sulfur and nitrogen are released. When these combine with water they produce sulfuric acid and nitric acid. Precipitation is considered to be acidic if the pH is less than 5.6. Has been in the news when Fort Drum helicopters drop lime on Adirondack Lakes to try to increase the pH. Acid rain dissolves calcium carbonate (CaCO3) like that found in limestone and concrete.

Effect on ecosystems Changes in pH level can kill everything in an ecosystem Also causes Aluminum to leach out of surrounding soils Accumulates in fish gills, causing increased mucus production, then suffocation Melting of snow in spring can cause acid shock because of the rapid increase of acidic water from the melting snow. May cause major fish kill and inhibit reproductive success of fish and amphibians. Many forests in the northeastern United States and Canada are dying off because of acid precipitation

The problem with acid precipitation is that the pollutants released in one area effect areas hundreds of miles away. The United Nations Helsinki Declaration in 1985 (not signed by the United States) and the United Nations Sofia Protocol in 1988 (signed by the United States) are documents that are trying to decrease these harmful emissions that cause acid precipitation.