Ambient Air Quality

Hazardous Air Pollutants (HAPs)

Emitted from industrial/manufacturing processes and motor vehicles 1970: congress told EPA to list highly toxic air pollutants Came up with only 8: asbestos, mercury, beryllium, benzene, vinyl chloride, arsenic, radionuclides, coke oven emissions 1990: under increased pressure from congress, EPA came up with 189 HAPs

Major stationary sources must:

Obtain operating permits Install pollution control equipment Meet specific emissions limitations

How to measure concentration of pollutants

ppm or ppb vs. mass/vol. (e.g. ug/m3) parts per million etc. vapors or gases

Ozone

"Sunburn of the lungs" Causes: Chest pain, coughing, airway inflammation. VOCs and Nitrogen chemically react. Pollutants bake together to form ozone. NO + VOCs + sunlight = ozone

Natural sources

Dust storms/drought Volcanic activity Wildfires

estimates of deaths due to outdoor air pollution

1.3-3.2 million worldwide per year

Particulate Matter (PM)

2.5 and 10. Haze. Some are emitted directly from a source, such as construction sites, unpaved roads, fields, smokestacks or fires. Most particles form in the atmosphere as a result of complex reactions of chemicals such as sulfur dioxide and nitrogen oxides, which are pollutants emitted from power plants, industries and automobiles. Harmful to lungs and bloodstream.

Sulfur Dioxide

Acid rain component. irritates airways in the human respiratory system. Such exposures over short periods can aggravate respiratory diseases, particularly asthma, leading to respiratory symptoms (such as coughing, wheezing or difficulty breathing)

Carbon Monoxide

Colorless, odorless gas that can be harmful if inhaled in large amounts. The greatest sources of CO to outdoor air are cars, trucks and other vehicles or machinery that burn fossil fuels. At very high levels, which are possible indoors or in other enclosed environments, CO can cause dizziness, confusion, unconsciousness and death.

Anthropogenic (manmade) sources of air pollution

Vehicles (90%), fossil fuel burning power plants, industrialization, waste incineration Industrial accidents and agricultural. Stationary sources: buildings, structures, facilities, etc. that emit air pollutants Mobiles

Natural determinants of air quality

Weather (e.g. thermal inversions) Prevailing winds, temperature

Nitrogen Dioxide

NO2 primarily gets in the air from the burning of fuel. NO2 forms from emissions from cars, trucks and buses, power plants, and off-road equipment. irritate airways in the human respiratory system. Such exposures over short periods can aggravate respiratory diseases, particularly asthma, leading to respiratory symptoms (such as coughing, wheezing or difficulty breathing). Acid rain

Criteria Pollutants

Particulate Matter (PM), Nitrogen Dioxide, Sulfur Dioxide, Lead, Ozone, Carbon Monoxide

The Clean air act gave the EPA authority to

Regulate emissions from stationary and mobile sources

Lead

Toxic to humans and animals Has very long half-life (accumulates in the body) Toxic effects on Liver Kidneys Nervous system

How outdoor air pollution affects human health

pollution, asthma, respiratory infections, heart disease, and lung cancer

NAAQS (National Ambient Air Quality Standards)

primary: public health protection secondary: public welfare protection