How Clean is our Air?

Investigating Air Pollution

What is Air?

Invisible, tasteless, and odorless mixture of gases that surrounds us

Two categoriesInside air

Air found inside buildings

Ambient airAir (atmosphere) outside

What is Air?

Major components of airNitrogen -78%

Oxygen – 21%

Argon – 0.9%

Carbon dioxide - 0.03%

Trace gases Neon, ammonia, helium, methane, krypton, hydrogen

Air Quality

Availability of quality air is critical to both plants and animal

Both ambient and inside air quality is important

What is Air Pollution?

The presence of materials in the air that damage air quality

Anything other than the natural gases present

Results fromNatural events

Human activity

Types and Sources of Air Pollution

Two major types of air pollutantsParticulate matterGases

Particulate Matter

Small particles similar to dust and droplets of liquid

Most visible and noticeable type of air pollution

Most air pollution is of this type

In cities, 90% is due to human intervention

Particulate Matter

Examples:Smoke from factories

Burning trash and forest fires

Dust from roads and mines

Lint

Pollen

Gases

Difficult to identify

Remain in the atmosphere for years

Classifications of gas pollutantsCarbon forms

Sulfur oxides

Nitrogen oxides

Carbon Forms

Released through combustion or burning of materials that contain carbon

IncludeHydrocarbons

Carbon monoxide (CO)

Carbon dioxide (CO2)

Hydrocarbons

Volatile organic compounds (VOC) Compound containing carbon that forms when sunlight reacts with chemicals in the atmosphere

Sources of chemicalsEvaporating gas and oil

Paints, primers, sealers

Organic chemicals (toluene, benzene, phenols, chloroform)

Carbon Dioxide and Carbon Monoxide

Internal combustion engines release carbon gases

Complete combustion = carbon dioxideIncomplete combustion = carbon monoxide

One billion metric tons of carbon monoxide released every year by vehicles alone Carbon dioxide is a major component of smog

Sulfur Oxides

High level can be detected by a “rotten egg –type” odorCommon sulfur oxides

Sulfur dioxide(SO2)

Sulfur trioxide(SO3)

Sulfur Dioxide

Produced when fuels containing sulfur are burned

Coal and oil

Natural sourcesVolcanoes

Sea spray

Dust from soil

Sulfur dioxide is the second major component of smog

Sulfur Trioxide

One major gas that causes acid rain Able to combine with water vapor to form sulfuric acid (H2SO4)

Very strong acid quickly reacts with materials when contract is made

Acid rain can cause damage to plants and property.

Nitrogen Oxides

Formed during combustion of fuels with nitrogen

Common forms Nitrogen monoxide (NO)

Nitrogen dioxide (NO2)

The effects of nitrogen oxides are similar to those of of sulfur oxides.

Another major gas that causes acid rain

The Effects of Air Pollution

Human health problemsmostly respiratory diseases

Common diseases Lung Cancer

Emphysema

Bronchitis

Black lung diseases

The Effects of Air Pollution

All air comes in through nostrils

small hairs and moist membranes that filter dust and some gases

Materials that get past the small hairs may be absorbed by the mucous membranes in lungs.

The Effects of Air Pollution

The Effects of Air Pollution

Air pollution affects lungs of other animals similar to humans

Feed produced in areas near high air pollution may be poisoned

Acid rain can also destroy wild fish population in lakes and streams if in a strong enough concentration

The Effects of Air Pollution

Air pollution may cause damage to fruits, vegetables, flowers, trees, lawn grasses, and other plants.

Several pollutants can destroy leaf tissue in plants.

Plant cannot manufacture the needed chlorophyll

Protecting Air from Pollution

Controlling emissionsScrubbers can be used on factory stacksUse fuels that produce less sulfur, carbon, and nitrogen Maintaining engines

less fuel is burned = fewer pollutants

Reusing and recycling Practicing safety