YSU Institute of Learning In Retirement
YSU Metro College

Air Quality--
Don’t Hold Your Breath

Alan M. Jacobs, Ph.D., P.G.

Professor and Chair

Department of Geological and Environmental Sciences

What did I do?

l   Environmental projects for State of Illinois

l   Engineering projects around the world

l   Abandoned mine inspections (down-hole TV) in the Appalachian region

l   Superfund site assessments and cleanups

l   Academia- Indiana, Carnegie-Mellon, and YSU

Air Quality--
Don’t Hold Your Breath

Alan M. Jacobs, Ph.D., P.G.

Professor and Chair

Department of Geological and Environmental Sciences

Food, water, air

 

l   We can do without:

–   Food for a few weeks

–   Water for a few days

 

l   But we can not do without:

–   Air for only a few minutes

If we were to hold our breath…

l    1 second

l    2 seconds

l    3 seconds

l    4 seconds

l    5 seconds

l    6 seconds

l    7 seconds

l    8 seconds

l    9 seconds

l    10 seconds

l    11 seconds

l    12 seconds

l    13 seconds

l    14 seconds

l    15 seconds

l    16 seconds

 

Oxygen Needs

l   Even though you can breath, the gases you breath in should have sufficient oxygen.

l   OSHA defines oxygen deficiency as less than 19.5%.

l   Too much oxygen, >23.5% and there is a greater risk of fire.

 

Oxygen Deficiency

l   Oxygen need: OSHA: 19.5-23.5%

–   Adverse health effects <16%; not detectable until it is too late

–   Impaired judgment, lack of coordination, increased breathing and heart rate

–   Severe deficiency can cause nausea, vomiting, unconsciousness, brain damage, and death

Cause of O2 Deficiency

l   Displaced by other gases

–   Heavier than air in low-lying places

 

l   Consumed by chemical or biological processes

–   Consumption by chemical processes (fire, slow oxidation, biological decay)

Origin of Oxygen?

l   Plants (photosynthetic organisms) produce oxygen and carbohydrates from water and carbon dioxide with energy from sunshine and the help of chloroplasts (green cells).

 

Carbon dioxide + Water          Carbohydrates + Oxygen

 

l   Respiration reverses the process and releases energy stored in carbohydrates.

 

 

Oxygen Pollution

l   >3.5 billions years B.P. no photosynthesis

l   at 3.5 billion first record of oxidized iron

l   3.5 to 2.0 billion- rocks absorbed all excess oxygen (red beds, oxide ores)

l   0.5 billion years B.P. oxygen accumulates in the atmosphere, ozone increases, and life proliferates.

 

 

NATURAL SOURCES OF AIR POLLUTION

l   Volcanoes - Ash and acidic components

l   Natural Fires - Smoke

l   Sea Spray - Sulfur

l   Vegetation - Volatile organic compounds

l   Bacterial Metabolism - Methane

l   Dust

–   Pollen

l   Viruses and Bacteria

 

Conventional Pollutants

l    Clean Air Act (1970) designated seven major (conventional) pollutants for which maximum ambient air levels are mandated.

–    Particulate Matter

–    Metals and Halogens

–    Nitrogen Oxides

–    Carbon Oxides

–    Volatile Organic Compounds

–    Sulfur Dioxide

–    Photochemical oxidants

Conventional Pollutants

l   Particulate Matter

–   Atmospheric aerosols (solid or liquid)

l   Respirable particles smaller than 2.5 micrometers are among most dangerous.

–   Anthropogenic particulate emissions amount to about 362 million metric tons annually.

Conventional Pollutants

l   Metals

–   Many toxic metals occur as trace elements in fuel.

l   Lead Emissions: 2 million metric tons.

–   Mercury

l   Bioaccumulation in aquatic ecosystems.

–   Nickel, beryllium, cadmium, arsenic…

l   Halogens (Fluorine, Chlorine, Bromine)

–   CFC’s

Conventional Pollutants

l   Nitrogen Compounds

–   Nitrogen oxides are reactive gases formed when nitrogen is heated above 650o C in the presence of oxygen, or when nitrogen compounds are oxidized.

l   Annual Emissions: 230 million metric tons

Conventional Pollutants

l   Carbon Oxides

–   Predominant form of carbon in the air is carbon dioxide. 

l   Increasing levels due to human activities.

l   Annual Emissions: 7-8 billion metric tons

–   Carbon monoxide is a colorless, odorless, toxic gas produced by incomplete fuel combustion.

l   Annual Emissions: 1 billion metric tons

Conventional Pollutants

l   Volatile Organic Compounds

–   Organic chemicals that are easily vaporized

–   Natural- methane

–   Anthropogenic - vinyl chloride (used for plastics), industrial solvents, dry-cleaning fluids, liquid fuels, formaldehyde, chloroform.

Conventional Pollutants

l   Sulfur Compounds

–   Natural sources of sulfur in the atmosphere include evaporation from sea spray, volcanic fumes, and organic compounds.

–   Predominant form of anthropogenic sulfur is sulfur-dioxide from fossil-fuel combustion.

l   Annual Emissions: 114 million metric tons

Conventional Pollutants

l   Photochemical Oxidants

–   Products of secondary atmospheric reactions driven by solar energy.

l   Ozone formed by splitting nitrogen dioxide.

l   Gases from sulfur and nitrogen oxides that produce acid rain

Hazardous Air Pollutants

l   asbestos

l   mercury

l   beryllium

l   benzene

l   VCM (vinyl chloride monomer)

l   arsenic

l   radionuclides

l   coke oven discharges

Air Pollution

 

Sources of Air Pollution
Mini-Workshop 1

Sources of Air Pollution-- Answers

Most to Least

l   Autos and trucks

l   Fossil fuel generating stations

l   Steel mills, smelters, refineries, paper mills

l   Gone are concerns from home heating and refuse burning

 

What do we do?

l   Particulate removal

l   Sulfur removal

l   Stack scrubbing

l   Control the combustion process

Particulate Removal

l   Bag House - Remove particles physically by trapping them in a porous mesh which allows air to pass through but holds back solids.

l   Electrostatic Precipitators - Fly ash particles pick up electrostatic charge as they pass between large electrodes in waste stream, and accumulate on collecting plate.

Sulfur Removal

l   Pretreatment of fuels

l   Switch from soft coal (with a high sulfur content) to low sulfur coal.

l   Change to another fuel (natural gas).

Stack Scrubbing

l   Converting those gases that contain unwanted pollutants going through the stack to a residue of liquid paste or powder.

l   Then the residue must be managed as a “solid waste.”

Combustion Control

l   In industry, control combustion temperatures and catalysts to avoid unwanted products discharged up the stacks.

l   For highway vehicles, control the combustion temperature and catalysts to avoid unwanted products discharge out the tailpipe.

 

Mini-Workshop 2

l   How does the proper use of catalytic converters on automobiles improve the health of the public?

Catalytic Converter- Answers

l   Run the engine hot at peak efficiency you minimize carbon monoxide and unburned hydrocarbons– however,

l   This produces the maximum amount of nitrogen oxides.

l   The catalyst (platinum, rhodium, or palladium) combines the CO with the NOx and produces nitrogen gas and carbon dioxide.

Health Effects

l    Overload of body defenses, fibrosis, irritation, inflammation or destruction of tissue, ulceration, pulmonary edema, hypersensitivity reactions, paralysis of the mucociliary escalator (SOx and NOx), mucous buildup, difficulty breathing, bacterial buildup, acute bronchitis, emphysema, pneumonia, cancer, displace or inhibit oxygen usage, depress the central nervous system.

Particulates- Inhalation

l   Bodies reaction to irritation of respiratory tissues is to sneeze or cough (expelling the particulates)

l   Nearly all particles >10 microns are removed by nasal hairs and mucous secretions; most > 3 microns are removed by mucociliary escalator

l   Some <3 suspended in lung cells and some deposited and difficult to remove.

Gases and Vapors - Inhalation

l   Some of the water-soluble gases and vapors will dissolve on mucous membranes;

l   Diluted and insoluble gases and vapors will enter the lung cells and then proceed to the bloodstream;

l   Hot or cold gases can damage respiratory tissues throughout respiratory tract.

Air Quality Hot Topics

l   Indoor Air Quality- Sick Building Syndrome

l   Acid Rain

l   Global Warming

 

Indoor Air Quality

l    Sick Building Syndrome (SBS) vs. Building Related Illness (BRI)

l    Sealed windows and inadequate ventilation

l    Synthetic fabrics

l    Combustion and cooking

l    Household chemicals

l    Outdoor sources entering through ventilators

l    Mold spores, pollen, bacteria, pet dander

l    Dry cleaning chemicals

l    Smoking- Vote NO on Issue 4; YES on Issue 5!

Indoor Air Pollution

l    EPA found indoor concentrations of toxic air pollutants are often higher than outdoor.

 

l    Less developed countries

also suffer from indoor air

pollution.

 

Acid Deposition

l   What is pH?  A measure of acidity or alkalinity.  Either condition causes a substance to be corrosive.

–   pH scale ranges from 0-14.

l   7 = Neutral; 

l   <7 = Acidic;

l   >7 = Basic (alkaline)

Acid Rain

l    Sulfuric acid from sulfur dioxide [SOx]

l      Nitric acid from NOx

l    From liquid rain or particulates

l    From lightning, vegetation, volcanoes, coal burning, autos

l    High stacks distribute pollutants

l    Unpolluted pH=5.6

l    Corrosive effects, leach heavy metals from sediments

l      Buffered by calcareous terrain

Acid Precipitation

Acid Deposition

l   Aquatic Effects

l   In lakes, reproduction is the most sensitive stage in fish life cycles.

l   Acidic lake water makes metals in the lake sediment dissolve and be more likely to be absorbed into the bodies of aquatic life.

Acid Deposition

l   Forest Damage

–   Air pollution and depositions of atmospheric acids are believed to be important causes of forest destruction in many areas.

l   Buildings and Monuments

–   Limestone and marble are destroyed by air pollution at an alarming rate.

–   Corroding steel in reinforced concrete weakens buildings, roads, and bridges.

Mini-Workshop 3

l   Why do unpolluted waters (unaffected by acid rain) have a pH of 5.6, and not 7.0?  7.0 is neutral.

Unpolluted at 5.6- Answer

l   Carbon dioxide in the air (at 0.035 %)

l   Combines with water vapor to produce carbonic acid (club soda)

l   Equilibrium between water vapor in the air and surface waters.

l   This is not acid rain, which must have a pH of less than 4.6.

Global Warming

l    Balance of CO2 and other heat-trapping (greenhouse) gases (methane, nitrous oxides, CFCs, water vapor) is disturbed by human activity

l    Is this enough to change climates?

l    Earth history has seen global warming and cooling with the ice ages

l    For additional discussion please see my website:

<http://www.cc.ysu.edu/~amjacobs/>