nnChap101.pptxAIR, NOISE, AND RADIATION - Moore
LIVING WITH THE EARTH
CHAPTER 10
AIR, NOISE, AND RADIATION
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Objectives for this Chapter
A student reading this chapter will be able to:
1. List and explain the reasons why air pollution is considered a national and global threat.
2. Discuss and describe the chemical and physical components of the atmosphere, and explain the mechanisms of dispersion.
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Objectives for this Chapter
A student reading this chapter will be able to:
3. Describe the regulatory efforts in the U.S. with emphasis on titles of the 1990 CAAA.
4. Discuss the issues behind stratospheric ozone depletion and global warming.
5. List and discuss the nature, sources, and health and welfare effects of the criteria pollutants.
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Objectives for this Chapter
A student reading this chapter will be able to:
6. List, discuss, and describe the major sources of indoor air pollution, including health effects and methods of control.
7. Define noise pollution and radiation. List the major sources and known health effects of noise and radiation.
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AIR NOISE AND RADIATION
Introduction
History
Edward I and II of Great Britain severely punished air polluters
Until 1930s (Meuse Valley, Belgium.) air pollution considered a nuisance.
Air pollution episodes in Donora, PA, London England, Losa Angeles, CA, NY City caused many deaths, raised public awareness.
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AIR NOISE AND RADIATION
Air pollution threatens global ecology
Consensus grows that industrial emissions such as carbon dioxide and other greenhouse gases, are contributing to global warming .
Chlorofluorocarbons may be depleting stratospheric ozone
Acid deposition
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AIR NOISE AND RADIATION
Air pollution threatens human health
asthma, bronchitis, emphysema, cancer, respiratory infections, irritation, cardiovascular disease
Air pollution threatens living plants and human-made structures
forest decline, corrosion of metal, soiling of buildings, degradation of paints, textiles, leather, paper, and dyes.
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THE ATMOSPHERE AND METHODS OF DISPERSION
Chemical Characteristics
Nitrogen (N2) represents a constant 78 percent of the 500 billion tons of air surrounding the planet, while oxygen (O2) remains steady at 21 percent, and argon (Ar) at 0.9 percent. (Fig. 10-1).
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Fig. 10-1
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Chemical Characteristics
Human technology and explosive populations could potentially alter the atmospheric balance of gases causing changes in the earth-atmosphere system that jeopardizes our sustainability.
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Physical Characteristics
Solar Radiation
The life on earth requires a continuing source of energy.
More than 99 percent of the energy from the sun is within the spectral range of 150 to 4,000 nanometers (0.15 to 4.0 µm) (Fig. 10-2).
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Fig 10-2
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Solar Radiation
Solar energy that is absorbed by ground surfaces is radiated back as heat in longer, lower energy, infrared wavelengths.
Greenhouse Effect
If this reflected heat energy (infrared) is absorbed by infrared-absorbing gases or water vapor, it traps the warmth and reflects it back to the earth's atmosphere (Fig. 10-3).
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Fig. 10-3
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Vertical Temperature Differences and Atmospheric Regions
You would normally experience a declining temperature as you gained altitude at a rate of about -6.5°C/km, or a loss of about 65°C over the zero to 10 km altitude range. This region is known as the troposphere (Fig. 10-4).
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Fig. 10-4
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Atmospheric Pressure and Density
About 99 percent of the atmospheric mass is below 30 km (18 miles), 90 percent is below 12 km, and 75 percent of the atmosphere is below 10 km (Fig. 10-5).
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Fig. 10-5
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Atmospheric Pressure and Density
Boiling the water atop a high mountain peak will occur at a lower temperature of perhaps 90°C, since the pressure is lower and gaseous vapors can escape more readily under lower pressure (Fig. 10-6).
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Fig. 10-6
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Atmospheric Pressure and Density
Friction, Coriolis force, and differential warming cause air to flow into regions of low pressure or in a cyclonic or motion and then to rise. (Fig. 10-7).
When cool air descends , it readitea outward in a motion known as anticyclonic. This motion is clockwise in the northern hemisphere (Fig. 10-7)
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Fig. 10-7
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Atmospheric Inversions
The warmer the air mass in relation to its surroundings, the more rapidly it will rise (Fig. 10-8).
Normal lapse rate
Adiabatic lapse rate
Environmental lapse rate
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Fig. 10-8
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Atmospheric Inversions
There are two primary types of inversions
Radiation inversion
Occur at night, and are short lived
Subsidence inversion (Fig. 10-9)
Occur mostly during fall and winter months, may persist for days.
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Fig. 10-9
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THE HISTORY OF AIR POLLUTION CONTROL IN THE UNITED STATES
1955- Congress authorized the Public Health Service in the Department of Health, Education and Welfare (DHEW)
1963- Clean Air Act
1967- Comprehensive Air quality act
1970- CAAA
1977- more amendments
1990 Clean Air Act Amendments
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Titles of the 1990 Clean Air Act Amendments
Title I: Provisions for Attainment and Maintenance of the NAAQS
The 1990 CAAA attempts to strengthen the provisions protecting the public against seven of the most widespread and common pollutants designated as criteria pollutants (Table 10-1).
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Table 10-1
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The 1990 CAAA
National Ambient Air Quality Standards (NAAQS).
Non-attainment areas
Air quality control regions
(BACT)
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Title II: Provisions Relating to Mobile Sources
Automobiles account for the greatest combined amount of criteria pollutants including carbon monoxide, hydrocarbons, and nitrogen-oxides.
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Title II: Provisions Relating to Mobile Sources
SOVs
Recapture nozzles
Reformulated gasoline
Methyl-t-butyl ether
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Title III: Air Toxics
Bhopal India, 1984
SARA “Right to know”
(MACT)
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Title IV: Acid Deposition Control
Acid Deposition
Emissions of nitrogen and sulfur oxides are partially converted in the atmosphere to nitric and sulfuric acids which return to the earth in rain, snow, fog and on dry particles.
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Title IV: Acid Deposition Control
Market-based principles
Emission banking
Trading
An allowance is defined under 1990 CAAA as the right to emit one ton of sulfur dioxide.
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Title V: Permits
Regulated sources must obtain a permit.
Based on program similar to National Pollution Elimination Discharge System (NPDES)
State programs must be approved by the USEPA.
Fee is charged to cover cost of permitting.
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Title VI: Stratospheric Ozone and Global Climate Protection
Mario Molina, Sherwood Rowland and Max Planck received the Nobel Prize for chemistry in 1995 for their work in establishing that CFCs were destroying the ozone layer (Fig. 10-10).
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Fig. 10-10
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Title VI: Stratospheric Ozone and Global Climate Protection
The World Meteorological Organization reports that the ozone hole over Antarctica peaked at 7.7 million square miles and lasting for 50 days.
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Title VI: Stratospheric Ozone and Global Climate Protection
Montreal Protocol
Phase out CFCs
Substitutes
As a result production is down and the accumulation rate of CFCs has decreased although the Antarctic stratospheric ozone levels are expected to decline for years (Fig. 10-11).
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Fig. 10-11
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Health and Welfare Impacts of Ozone Depletion
The destruction of the ozone layer could result in:
1. Increases in basal and squamous cell skin cancer;
2. Suppression or weakening of the human immune response system;
3. Damage to the cornea and conjunctiva of the eye;
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Health and Welfare Impacts of Ozone Depletion
The destruction of the ozone layer could result in:
4. Reduction in plant leaf size, total dry weight, and stunting of plant growth; and
5. decreased amounts of phytoplankton and zooplankton.
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Revised Ozone and Particulate Standards
Ground-level ozone is a major component of smog that is photochemically produced as a secondary pollutant of the stratosphere from the interaction of sunlight, nitrogen oxides and hydrocarbons.
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Revised Ozone and Particulate Standards
Ozone
1979- 0.12 ppm, one hr
1997- 0.08ppm, eight hours
Particulates
24 hr PM2.5 - 65g/m3
Annual PM10 - 50g/m3
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The Issue of Global Warming
The Hot Air Treaty, Kyoto, Japan
The global warming treaty completed in December 1997 (Kyoto, Japan), asked Western nations to reduce greenhouse gases to pre-1990 levels by 2010.
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Global Warming: The Controversy
Human activities may have upset the balance of atmospheric carbon dioxide through:
(1) the combustion of fossil fuels which releases carbon oxides;
(2) the burning of forests which produces CO2 and removes a vital consumer of CO2; and
(3) the destruction of phytoplankton by pollution of the oceans.
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Global Warming: The Controversy
An increasing blanket of carbon dioxide around the planet absorbs some of the IR energy radiating away from the earth, trapping it and causing the earth to warm in a process known as the greenhouse effect (Fig. 10-12).
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Fig. 10-12
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Global Warming: The Controversy
Global warming is a concern because:
(1) icebergs the size of small states have broken off the Antarctic ice shelf;
(2) the annual average global temperature has risen by about 0.5C (1°F) since the 19th century;
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Global warming is a concern because:
(3) global sea is rising faster (3 min/yr);
(4) 1990, 1995, and 1997 were the warmest years in the last 600 yrs;
(5) mountain glaciers are rapidly retreating.
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Global Warming: The Controversy
Climate is affected by:
1. increases in atmospheric gases that absorb energy;
2. changes in the earth's orbital geometry;
3. changes in oceans temperature;
4. volcanic activity; and
5. variations in solar radiation.
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Factors Effecting Global Climate Change
Orbital Geometry As A Factor Effecting Climate
Records show that mean global temperatures fluctuated widely with transitions from warm to cold often measured in decades (Fig 10-14).
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Fig. 10-14
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What events caused such drastic changes?
Milankovitch theories
Eccentricity
Obliquity
Brodkerad and Denton
Ocean currents
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Factors Effecting Global Climate Change
El Nino
El Nino is a change or shift in ocean temperatures along with atmospheric conditions in the tropical Pacific that changes weather patterns all around the world (Fig. 10-15).
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Fig. 10-15
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Factors Effecting Global Climate Change
Volcanic Activity
Volcanic eruptions in the modern era may have extreme localized effects on land, and may cause short-term global changes in weather patterns as sunlight is inhibited by a layer of particles thrust into the atmosphere.
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Factors Effecting Global Climate Change
Solar Radiation
Sunspots show cycles of 11 and 22 years that correlate with nearly half of the global warming evidenced over the last 100 years.
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The Criteria Pollutants
Introduction
Nearly 46 million people live in counties that fail to meet the air quality standards for one or more of the criteria pollutants (Table 10-2).
A summary of criteria pollutants sources, health and welfare effects is presented in Table 10-3.
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Table 10-2
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Table 10-3
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The Criteria Pollutants
Particulate Matter
Particulate pollutants include airborne particles in liquid solid form that range in size from visible fly ash greater than 100 µm to particles 0.005 µm in size (Table 10-4).
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Table 10-4
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Ozone And The Photochemical Oxidants
An oxidant is a substance that readily gives up an oxygen atom, or removes hydrogen from a compound.
Photochemical refers to the initiation of these reactions by sunlight.
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Ozone And The Photochemical Oxidants
Good O3 vs. Bad O3
The bad ozone is formed on the troposphere (nose-level) by a complex series of reactions (10-16).
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Fig. 10-16
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The Criteria Pollutants
Carbon Monoxide
produced from the incomplete combustion of fossil fuels
enters the blood streams through the lungs and combines with hemoglobin of red blood cells to form carboxyhemoglobin.
levels of carboxyhemoglobin rise and the adverse effects associated with oxygen deficiency are observed.
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The Criteria Pollutants
Lead
The association of lead with behavioral problems and reduced intellectual ability caused lead to be placed on the list of criteria pollutants in 1977 when the Clean Air Act was re-authorized.
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The Criteria Pollutants
Lead
The phase-out of leaded gasoline has been the predominant control strategy.
Lead emissions from highways have decreased 99 percent since 1987
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Sulfur or Oxides
Health and Welfare Effects
The primary source of sulfur emissions are electric utilities.
Health concerns associated with SO2 include respiratory illness, effects on breathing, a reduction in lung defenses, and aggravation of existing cardiovascular disease.
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Sulfur or Oxides
Acid Deposition
Sulfur oxides are among the main precursors to acid deposition, with nitrogen oxides being the second greatest contribution.
Since acidity may be found in rain, sleet, snow, fog, clouds, and adsorbed to particle, the term acid rain is being replaced by the term acid deposition.
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Effects of Acid Deposition on Ecology
Long distance transport
Acidification of acid sensitive ecosystems (Fig. 10-17)
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Fig. 10-17
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Effects of Acid Deposition on Ecology
Aquatic Systems
The spring thawing of acidic ice and snow results in shock loading.
The aquatic life in a body of water will experience recruitment failure when the pH falls below 5.5.
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Effects on Forests and Plants:
1. directly damages leaves;
2. mobilizes toxic metals in the soil;
3. leaches nutrients from soil;
4. excess nitrates over stimulates plants.
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Current Directions in SOx Control:
(1) switching to low sulfur coal;
(2) using scrubbers to remove SO2 emissions;
(3) washing coal removes up to 50% of the sulfur;
(4) advanced combustion technologies.
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HEALTH IMPLICATIONS OF AIR POLLUTANTS
Fine particulates from motor vehicles and power plants are reported to kill some 64,000 Americans a year and may be a major contributor to the epidemic of childhood asthma sweeping the country (Fig. 10-18, 19).
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Fig. 10-18
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Fig. 10-19
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Main Mechanisms of Air Pollutant Effects on Respiratory System
Pollutants may produce their adverse effects by:
(1) inhibiting and inactivating mucociliary streaming;
(2) killing or neutralizing alveolar macrophages;
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Pollutants may produce their adverse effects by:
(3) constricting airways;
(4) causing vasodilation and excess mucous secretion; or
(5) causing changes in alveolar cell wall structure through abscesses and thickening which causes scar formation.
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Indoor Air Pollution
People spend an average of 90 percent of their time indoors while some at-risk subgroups such as the elderly, very young, and chronically ill may spend nearly all their time indoors.
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Sources of Indoor Air Pollution
Acid, coal, gas, oil
Cleaning products
Furnishings, carpets
Paints (VOCs)
Radon
Moisture, molds, etc.(Fig. 10-20)
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Fig. 10-20
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Sources of Indoor Air Pollution
Ventilation is an effective way to reduce indoor concentrations of contaminants.
Natural Ventilation
Infiltration
Mechanical Ventilation
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Signs of Indoor Air Pollution
Physical symptoms may include:
(1) heating or cooling equipment that is dirty and/or moldy;
(2) moisture condensation on walls and windows;
(3) air that has a stuffy or has an unpleasant odor; and
(4) signs of water leakage anywhere in the building with the growth of molds.
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Signs of Indoor Air Pollution
Health indicators may include:
immediate or acute effects such as eye irritation, dry throat, headaches, fatigue, sinus congestion, sun irritation, shortness of breath, cough dizziness, nausea, sneezing, and nose irritation.
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Signs of Indoor Air Pollution
When a number of occupants of a building display acute symptoms without a particular pattern and the varied symptoms cannot be associated with a particular source, the phenomenon is often referred as sick building syndrome (SBS).
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Common Sources of Indoor Air Pollution
The most common sources of indoor pollution include: environmental tobacco smoke, radon, biologicals, nitrogen dioxide, carbon monoxide, organic gases, formaldehyde, respirable particles and pesticides.
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Environmental Tobacco Smoke (ETS and Other Combusted Materials)
Smoking contributes to nearly 500,000 deaths each year in the United States.
Main-stream smoke
Side-stream smoke
Environmental tobacco smoke (ETS)
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Radon
Radon is a colorless, odorless gas that occurs naturally by the decay of radium-226.
As the uranium naturally radioactively decays it releases radon gas that further decays into short-lived, radon daughters and gamma rays (Fig. 10-21).
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Fig. 10-21
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Radon
Once lodged in human tissue, the radioactive materials increase the risk of lung cancer causing from 5,000 to 20,000 excess cancer deaths a year in the United States.
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Radon Detection
FCR 4pCi/L or above calls for action
Alpha track detectors
Mitigation
Basement ventilation
Sealing cracks, joints, walls, etc.
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Biological Contamination
Common biological contaminants include molds, mildew, viruses, bacteria, dust mites, cockroaches, pollen, animal dander, and cat saliva.
The major threat to the biological contaminant of the home is moisture.
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Biological Contamination
Possible symptoms of illness caused by biological contaminants include running nose, colds, flu-like symptoms, headaches, unexplained fatigue, and digestive problems.
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Organic Gases, Pesticides
Paints, strippers, disinfectants, cleaners, repellants, automotive products, hobby supplies, volatile office supplies, and pesticides which are found indoors can emit potentially hazardous materials.
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Formaldehyde (HCHO)
Formaldehyde is found in pressed wood products such as cabinets and furniture made from plywood, particleboard, wall paneling, and fiberboard.
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Formaldehyde (HCHO)
Exposure to formaldehyde can produce adverse health effects include irritation to the mucous membranes, severe allergic reactions, fatigue, wheezing and coughing.
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Noise
Introduction
Sound itself is not a pollutant, but when it interferes with tasks, when it distracts, annoys or disturbs, or when it causes losses in hearing or alters physiology in negative way then it becomes unwanted sound, or noise.
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The Physics of Sounds
Sound is a form of energy that is produced by the vibration of objects which compress and expand air, water or solids to produce waves.
Frequency and Amplitude (Fig. 10-22, 23)
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Fig. 10-22
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Fig. 10-23
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The Physics of Sounds
Soft sounds have a low amplitude while loudness is characterized by large amplitudes.
This amplitude intensity or loudness is measured in decibels (dB)[Fig. 10-24].
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Fig. 10-24
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Physiology of Sound and Health Effects
Sounds enters the ear and the tympanic membrane vibrates.
The tympanic membrane is connected to a series of three very small bones in the middle ear known as the malleus, incus, and stapes which transmit the vibration to the oval window of small-shaped structure called the cochlea (Fig. 10-25).
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Fig. 10-25
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Physiology of Sound and Health Effects
Excessive sound pressure (loud noises) can destroy the delicate hairs in the spiral organ.
Hearing loss is known as permanent or temporary threshold shift (PTS or TTS).
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Regulation of Noise
The regulation of sound requires that it be measured according to a standard.
Department of Labor with a permissible exposure limit of 90dBA for an eight hour day, 40 hour work week.
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Radiation
Introduction
Atoms are the basic units of elements and consist of a small dense center called a nucleus surrounded by a cloud of negatively charged electrons (Fig. 10-27).
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Radiation
When a radioisotope decomposes, it releases energy in the form of electromagnetic radiation (g or x- rays), and energy of motion from particles (a or b) [Fig. 10-27].
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Fig. 10-27
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Radiation
An atom which is missing one or more electrons is referred to as an ion, and energetic radiation capable of doing this is called ionizing radiation.
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Radiation Exposure
Every individual comes into contact with ionizing radiation from three general types of sources:
(1) naturally occurring (cosmic rays, minerals);
(2) naturally occurring but enhanced by human actions; and
(3) human generated (fallout).
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Health Impacts of Ionizing Radiation
Dose
High vs. low
Dose rate
Time span for a certain exposure may be more important than total dose.
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Health Impacts of Ionizing Radiation
Radiation Induced Mutations
Birth Defects
Radiation-Induced Cancer
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Radiation and Nuclear Power Generation
Nuclear power production involves a number of steps, referred to as the nuclear fuel cycle.
Mining the Uranium
Processing
Converting
Enriching
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Ultraviolet Radiation
Wavelengths of the electromagnetic spectrum ranging between 40-400 nanometers in length are categorized as ultraviolet (UV) light.
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Ultraviolet Radiation
Injury to the hereditary material of cells is the reason for the lethal or mutational effects which excess UV exposure can provoke in living organisms.
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Ultraviolet Radiation
Three major types of skin cancer account for over 700,000 new cases of the disease diagnosed in the U.S. each year.
Basal cell carcinoma
Squamous cell carcinoma
Malignant Melanoma
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Ultraviolet Radiation
Some Beneficial Effects
Needed to produce Vitamin D
Germicidal properties
Treat bacterial skin diseases
