AIR QUALITYAIR QUALITY

Consider:Consider:

An oxygen tank costs $50. An oxygen tank costs $50. 1,000,000 Americans wouldn1,000,000 Americans wouldn’’t need 2 tanks t need 2 tanks

per week for emphysema/bronchitis if air per week for emphysema/bronchitis if air pollution is decreased.pollution is decreased.

A savings of $5.2 billion dollars yearly.A savings of $5.2 billion dollars yearly.Why do you care? Why do you care?

Insurance/TaxesInsurance/Taxes

The AtmosphereThe Atmosphere

Whole mass of air around the earthWhole mass of air around the earth Components:Components:

78% N78% N22, 21% O, 21% O22

Water, Carbon dioxide (0.03%), Water, Carbon dioxide (0.03%), helium, helium, etc. make up the remainder. etc. make up the remainder.

Realize- earthRealize- earth’’s circumference is 24,800 s circumference is 24,800 miles. Atmosphere is FINITE!!!miles. Atmosphere is FINITE!!!

Layers of the AtmosphereLayers of the Atmosphere

DID YOU KNOW?DID YOU KNOW?Mexico City has some of the worst air quality Mexico City has some of the worst air quality

in the world. Over 22 million people in a in the world. Over 22 million people in a valley 7575 ft above sea level. valley 7575 ft above sea level.

Cars are less efficient, pollutants are trapped Cars are less efficient, pollutants are trapped in valley, little air quality legislation for in valley, little air quality legislation for business all result in business all result in ““bad airbad air””..

Air PollutionAir Pollution

any substance in the air that causes harm any substance in the air that causes harm to living organisms.to living organisms.

TWO TYPES:TWO TYPES:

1.1. Natural—volcanoes, pollen, forest fire Natural—volcanoes, pollen, forest fire smoke, saltsmoke, salt

2.2. Human Activity—produced by US!!!Human Activity—produced by US!!!

2. Human Activity cont.2. Human Activity cont.

Two forms of Pollution Due to Human ActivityTwo forms of Pollution Due to Human Activity

a.a. Primary—released directly into the Primary—released directly into the atmosphere as a pollutant.atmosphere as a pollutant.

Includes: soot, CO, NOIncludes: soot, CO, NOxx, SO, SOxx, VOC, VOC’’s (volatile s (volatile

organic compounds), COorganic compounds), CO22

Human Activity cont.Human Activity cont.

b.b. Secondary—primary pollutants combine Secondary—primary pollutants combine with other compounds to produce pollutantswith other compounds to produce pollutants

Includes:Includes:

*Smog—smoke + fog*Smog—smoke + fog

*Ozone—UV light + exhaust + Oxygen*Ozone—UV light + exhaust + Oxygen

*Acid ppt—SO*Acid ppt—SOxx + NO + NOxx + H + H22O vaporO vapor

Temperature InversionsTemperature Inversions

Cold, cloudy weather in a valley surrounded by Cold, cloudy weather in a valley surrounded by mountains can trap air pollutants (left).mountains can trap air pollutants (left).

Areas with sunny climate, light winds, mountains Areas with sunny climate, light winds, mountains on three sides and an ocean on the other (right) on three sides and an ocean on the other (right) are susceptible to inversions.are susceptible to inversions.

Figure 19-5Figure 19-5

Sunlight plus Cars Equals Sunlight plus Cars Equals Photochemical SmogPhotochemical Smog

Mexico City is one Mexico City is one of the many cities of the many cities in sunny, warm, dry in sunny, warm, dry climates with many climates with many motor vehicles that motor vehicles that suffer from suffer from photochemical photochemical smog.smog.

Figure 19-4Figure 19-4

Sunlight plus Cars Equals Sunlight plus Cars Equals Photochemical SmogPhotochemical Smog

Photochemical smog is a mixture of air Photochemical smog is a mixture of air pollutants formed by the reaction of nitrogen pollutants formed by the reaction of nitrogen oxides and volatile organic hydrocarbons oxides and volatile organic hydrocarbons under the influence of sunlight.under the influence of sunlight.

Acid PrecipitationAcid Precipitation

Cars/Factories/PowerPlantsCars/Factories/PowerPlants NOx + SOx + HNOx + SOx + H22O O HNO HNO33 + H + H22SOSO44

Kills plants by leaching nutrients into the soil, destroys leaves. Kills plants by leaching nutrients into the soil, destroys leaves.

Kills fish, invertebrates by Kills fish, invertebrates by ““suffocationsuffocation””..

Destroys buildings, paint, etc.Destroys buildings, paint, etc.

ACID PRECIPITATIONACID PRECIPITATION

Acid deposition consists of rain, snow, dust, Acid deposition consists of rain, snow, dust, or gas with a pH lower than 5.6.or gas with a pH lower than 5.6.

Figure 19-6Figure 19-6

Fig. 19-9, p. 451

Emissions

SO2 NOxAcid deposition

H2O2 O3

Others

Direct damage to leaves & bark

Reduced photo-synthesis and growth

Susceptibility to drought, extreme cold, insects, mosses, & disease organisms

Soil acidification

Tree death

Leaching

of soil nutrients

Release of toxic metal ions

Root damage

Reduced nutrient & water uptakeAcids

Lake

Groundwater

PANs

DID YOU REALIZE?DID YOU REALIZE?

• 1/3 of air pollution comes from cars1/3 of air pollution comes from cars

• 2/3 sulfur oxides and 1/3 nitrogen oxides 2/3 sulfur oxides and 1/3 nitrogen oxides come from electrical plantscome from electrical plants

• Companies buy/sell emission rights!!Companies buy/sell emission rights!!

DID YOU KNOW?DID YOU KNOW?

The first Clean Air Law was designed in the The first Clean Air Law was designed in the 12001200’’s by King Edward I. He was tired of s by King Edward I. He was tired of the smell from burning low quality coal. the smell from burning low quality coal.

He made it illegal and hung a violator in He made it illegal and hung a violator in 1273!!!1273!!!

Moral of the Story—donMoral of the Story—don’’t burn stinky stuff!!t burn stinky stuff!!

CLEAN AIR ACTCLEAN AIR ACT

1970 and 1990—EPA regulations for air quality.1970 and 1990—EPA regulations for air quality. Reduced carbon, nitrogen and sulfur oxides as well as Reduced carbon, nitrogen and sulfur oxides as well as

particulates.particulates. Cut lead pollution by 98% by 1997. Cut lead pollution by 98% by 1997.

-got rid of leaded gasoline, -got rid of leaded gasoline, mandated catalytic convertersmandated catalytic converters

Catalytic Converter- Reduced vehicular pollutants 20X!!!!Catalytic Converter- Reduced vehicular pollutants 20X!!!! 32% less pollutants in air than in 1997.32% less pollutants in air than in 1997. Problem – 220 million Americans still breathe air 100X Problem – 220 million Americans still breathe air 100X

more polluted than desired.more polluted than desired.

Chloroform

Benzo--pyrene

Styrene

Radon-222

Methylene Chloride

Tobacco Smoke

Carbon Monoxide

Asbestos

Nitrogen Oxides

1, 1, 1-Trichloroethane

Particulates

FormaldehydeTetrachloroethylene

Para-dichlorobenzene

Fig. 19-11, p. 453

Case Study: Radioactive RadonCase Study: Radioactive Radon

Radon-222, a Radon-222, a radioactive gas radioactive gas found in some found in some soils and rocks, soils and rocks, can seep into can seep into some houses and some houses and increase the risk increase the risk of lung cancer.of lung cancer.

Sources and paths of entry Sources and paths of entry for indoor radon-222 gasfor indoor radon-222 gas.

Figure 19-13Figure 19-13