Air Pollution

By Andrew Kielar andBrannock Furey

Layers of the Atmosphere Atmosphere Divided into

several layers Troposphere Stratosphere Mesophere Thermosphere

Many sharp differences occur across layers

Troposphere

Layer closest to the surface

Very thin Majority of air

mass located here Recycles nutrients

Stratosphere

Second layer About 2.5 times as

big as the troposphere

Works as a “sunblock” for the Earth

Contains the O-zone layer and also has the highest concentration of O-zone(O3)

2 Types of Pollution Sources Air pollution Air pollution

comes from either natural or human sources

Natural Pollution Human Pollution

History of Air Pollution

Industrial Revolution

London United States Health Effects

Hybrid Pollutants

2 types of pollutants Primary Secondary

Effects of winds Good News Bad News Indoor Air Pollution

Indoor Air Pollutants

Carbon Oxides Nitrogen Oxides

and Nitric Acid Sulfur Dioxide and

Sulfuric Acid Patriculates O-Zone VOCs

Lead

Does not break down in the Environment

Fairly common negative effects America

Effect on Children is steadily decreasing

Burning Coal

Cities that commonly burned coal were subject to industrial smog

Coal is commonly used to produced electricity

Currently, risk of smog is cut down because of safer and more regulated burning practices

Photochemical Smog

Photochemical Reaction

Photochemical Smog

Influences of weather on Photochemical smog

Effect on modern cities

Variables of Air Pollution

Increase Urban Buildings Hills and Mountains High Temperatures Natural VOCs Grasshopper Effect Temperature

Inversions

Decrease Gravity Precipitation Salty Ocean Air Winds Chemical Reactions

Acid Deposition

Pollution from smokestacks

Pollutants Acid deposition Largest acid

releases in Midwest

International Acid deposition

Harmful Effects

Human Respiratory diseases

Damages human-made structures

Pollute water Harm aquatic

ecosystems Affect plant life

and vegetation

Indoor Air Pollution

Developing countries: indoor burning of wood, charcoal, dung, crop residues, and coal exposes people to dangerous levels of air pollution

WHO and World Bank: indoor air pollution is, for poor people, the world’s most serious air pollution problem

Developed countries – Typical sources of indoor air pollution: asbestos, carbon monoxide, Radon-222, formaldehyde, etc.

EPA Studies: (1) levels of 11 common pollutants generally 2 – 5 times higher inside U.S. homes and commercial buildings than outside, (2) pollution levels inside cars in urban areas can be up to 18 times higher than outside levels, and (3) health risk from exposure to such chemicals magnified because people in developed countries spend most of their time indoors.

Indoor Air Pollution

Living organisms and their extrements – dust mites and cockroach droppings – important role in almost threefold increase of asthma in the U.S.

Airborne spores of molds and mildew Sick-building syndrome => Almost 1 in 5 commercial

building in the U.S. is considered “sick” Four most dangerous indoor air pollutants: tobacco

smoke, formaldehyde, radioactive radon-222 gas, and very small particles

Formaldehyde => people exposed have a 34% higher than normal risk of getting Lou Gehrig’s disease

Indoor Air Pollution – Radioactive Radon Gas

Radon-222: concentrated in underground mineral deposits. In buildings above these deposits, radon gas can seep in, build up to high levels, and decay into solid particles of other radioactive elements. Inhalation of these over long period of time => lung cancer

Health Effects of Air Pollution Body’s numerous defenses in respiratory system – nasal

hairs, sneezing and coughing, cilia – can be overwhelmed by prolonged or acute exposure to air pollutants. Can lead to: asthma, chronic bronchitis, emphysema

WHO: at least 3 million people worldwide die prematurely each year from the effects of air pollution

In the U.S., EPA estimates that 150,000 – 350,000 annual deaths are related to indoor and outdoor pollution

EPA: each year, more than 125,000 Americans get cancer from breathing soot-laden diesel fumes from buses and trucks Proposed stricter emission standards

2007 study: emissions from ocean-going ships are responsible for 60,000 premature deaths each year worldwide

Laws and Regulations for Air Pollution

Congress passed Clean Air Acts in 1970, 1977, 1990: established air pollution regulations

EPA directed to establish “national ambient air quality standards” for six outdoor “criteria pollutants”: carbon monoxide, nitrogen oxides, sulfur dioxide, suspended particulate matter, ozone, and lead.

EPA has established national emission standards for more than 188 “hazardous air pollutants”

“Toxic Release Inventory” (TRI) requires 21,500 refineries, power plants, mines, and factories to report their releases and waste management for 667 toxic chemicals.

2007 EPA report: combined emmissions of the six major air pollutants decreased 49% between 1980 and 2006.

Arrival of low-sulfur diesel fuel => push for new generation of diesel engines

U.S. Air Pollution Laws Can be Improved

Environmental scientists point to the following deficiencies of U.S. air pollution laws: The U.S. continues to rely mostly on pollution cleanup rather than

prevention For decades, the US. Congress failed to increase fuel-efficiency

standards for cars, SUVS, and light trucks. Regulation of emissions from motorcycles and two-cycle gasoline

engines remains inadequate. There is little or no regulation of air pollution from oceangoing ships

in American ports. Airports are exempt from many air pollution regulations. The laws do not regulate emissions of the greenhouse gas CO2

Ultrafine particles are not regulated. Urban ozone levels are still too high in many areas. The laws have failed to deal seriously with indoor air pollution. There is no need for better enforcement of the Clean Air Acts.

The Marketplace Can Help Reduce Outdoor Air Pollution

Clean Air Act of 1990: for SO2 – an “emissions trading”, or “cap-and-trade program” which enables the 110 most pollution power plants

Proponents: Cheaper and more efficient than government-run program

Critics: Allows dirtier, older plants to keep polluting Between 1990 and 2006, the emissions trading

system helped to reduce SO2 emissions from electric power plants in the United States by 53% at a cost of less than 1/10 the cost projected by industry.

Ways to Reduce Outdoor Pollution

Stationary Source Air Pollution: Prevention: Burn low-sulfur coal, Remove sulfur from coal,

Convert coal to a liquid or gaseous fuel, Shift to less polluting energy source

Dispersion or Cleanup: Disperse emissions above thermal inversion layer with tall smokestacks, Remove pollutants after combustion, Tax each unit of pollution produced

Motor Vehicle Air Pollution Prevention: Use mass transit, Walk or bike, Use less pollution

fuels, Improve fuel efficiency, Get older, polluting cars off the road, Give large tax write-offs or rebates for buying low-polluting, energy-efficient vehicles

Cleanup: Require emission control devices, Inspect car exhaust systems twice a year, Set strict emission standards

Reducing Indoor Air Pollution Prevention

Clean ceiling tiles and line AC ducts to prevent release of mineral fibers

Ban smoking or limit it to well-ventilated areas Set stricter formaldehyde emissions standards Prevent radon infiltration Use office machines in well ventilated areas Use less polluting substitutes for harmful cleaning angents, paints,

and other products Cleanup or Dispersion:

Use adjustable air vents for work spaces Increase intake of outside air Change air more frequently Circulate a building’s air through rooftop greehouses Use efficient venting systems for wood-burning stoves Use exhaust hoods for stoves and appliances burning natural gas

Reducing Air Pollution

Outdoor Improve energy efficiency to reduce fossil fuel use Rely more on lower-polluting natural gas Rely more on renewable energy Transfer energy efficiency, renewable energy, and pollution

prevention technologies to developing countries Indoor

Reduce poverty Distribute cheap and efficient cook stoves or solar cookers to

poor families in developing countries Reduce or ban indoor smoking Develop simple and cheap tests for indoor pollutants such as

particulates, radon, and formaldehyde