Air Pollution

15.4

Definition:

• Chemical or physical agent that when added to the environment impacts people, wildlife, plants or ecosystems.

• Natural causes

• Human causes

Monitoring Air Quality

• Lichens = natural indicators of air quality

• Monitoring stations take air samples on a continuous basis and provide alerts to state & federal agencies.

Primary pollutants

• Released directly into the air

• Examples of natural primary pollutants:

• Dust

• Sea salt

• Volcanic gas & ash

• Forest fire smoke

• Pollen

Primary pollutants

• Human sources of primary pollutants:

• Carbon monoxide

• Dust

• Smoke

• Paint

• Vehicle exhaust

• Burning fossil fuels

Examples of primary pollutants:

• SO2 Burning coal

• CO & CO2 Burning hydrocarbons

• NOx Fuel combustion

• Smog formed through solar action

• Particulates industry, agriculture, urban

Secondary pollutants

• Enter the air and undergo reactions

• Photochemical smog

• Acid rain

National Ambient Air Quality Standards (NAAQS)

• Ozone

• Particulate matter

• Carbon monoxide

• Sulfur dioxide

• Nitrogen oxides

• Lead

Indoor pollution

• Tobacco smoke

• Hydrocarbons

• Vinyl chlorides

• Asbestos

• Carbon monoxide

• Radon

Acid precipitation

• Sulfur dioxide + rain = sulfuric acid

• Nitrogen oxide + rain = nitric acid

• Problems with acid rain:– Forests: damages plants & habitats– Amphibian populations decline with acidity– Plants damaged– Aquatic ecosystems decline

Ozone hole

• 1985 discovered

• Caused by CFCs breaking down ozone

• Montreal Protocol (treaty) to eliminate CFC production

• Problem: it reduces the ability to block UV rays

CFC Molecules

• Active for 60 – 120 years

• Affect ozone layer of the atmosphere

Human Health

• Groups most susceptible: – Children– Elderly people– People with asthma, allergies, lung problems

& heart problems

Long term effects of exposure

• Emphysema

• Lung cancer

• Permanent lung damage

• Heart disease

Short term effects

• Headache

• Nausea

• Eye irritation

• Coughing

• Asthma aggravation

• Emphysema aggravation

Human Health impacts

• Lead = central nervous system damage

• Smog

• Sulfur dioxide = damages lung tissue

• Carbon monoxide = toxic. Binds to hemoglobin & displaces oxygen

• Particulates = damage respiratory tissue

Solutions

• Clean Air Act = incentives & penalties– Passed in 1970– Purpose: control of air pollutants, setting

standards for clean air

Reducing Pollution

• Scrubbers on smoke stacks

• Cleaner burning fuels

• Hybrid cars

• Catalytic converters in engines

• Remove source of pollution from indoors

• Improve ventilation indoors

Allowance Trading allows:

• Companies to sell pollutants that they’ve been allowed to discharge

Airnow Website

• http://airnow.gov/index.cfm?action=airnow.displaymaps&Pollutant=OZONE&StateID=60&domain=super