Ozone Depletion, Indoor & Outdoor Air Pollution

ART of ozone depleting substances?

75 - 150 years. Ozone depletion will continue until the mid 21st century.

Asbestosis, _____, mainly in ____

Asbestosis, lung cancers, mainly in workers exposed to high levels

Human health effects of nitrogen oxides

Damage to lung tissue and reduction in lung function. Other impacts from ozone include damaged vegetation and reduced crop yields. NOx and sulfur dioxide react with other substances in the air to form acids, which fall to earth as rain, fog, snow or dry particles. Additional nitrogen accelerates "eutrophication," which leads to oxygen depletion and reduces fish and shellfish populations. One member of the NOx, nitrous oxide, is a greenhouse gas. It accumulates in the atmosphere with other greenhouse gasses causing a gradual rise in the earth's temperature.

How can we control acid deposition?

Decrease emissions of SOx and NOx

Air quality is worse in _____

Developing countries

How is ozone formed and destroyed?

Diatomic oxygen is split, O atoms combine with oxygen molecules, and additional UV splits ozone into O2 and O, which recombines to form O3.

What are fugitive sources?

Do not go through pipe or smokestack

What is ozone measured in?

Dobson Units (DU)

What are some landmark events of outdoor air pollution?

Donora, Pa 1948. London, England 1952.

What wavelength of UV radiation is damaging for life on land?

0.1 - 0.4 micrometers

___ Cl atom can destroy ____ molecules

1 Cl atom can destroy 100,000 O3 molecules

How many parts per billion is one DU?

1 DU = 1 ppb

How can we use flue gas scrubbing to reduce SOx?

Lime injected into exhaust

Describe the Montreal Protocol (1987).

Limited production of O3 depleting substances. Signed by over 150 countries. Not all countries signed, most notably China and India. Increased standard of living in those countries has increased CFC's.

Define chronic

Long term or repeated exposures causes adverse effects (asbestos). Effects show up later.

What are the effects of acid deposition in forest ecosystems?

Loss of nutrients from soil, stresses trees, makes them susceptible to drought and parasites, disrupts whole ecosystem.

What is a health effect of radon?

Lung cancer

Define residual volume

Air remains after exhalation, not exchanged

Describe percent change in emissions?

All emissions are going down

Environmental effects of carbon monoxide

Although carbon monoxide is only a weak greenhouse gas, its influence on climate goes beyond its own direct effects. Its presence affects concentrations of other greenhouse gases including methane, tropospheric ozone and carbon dioxide.

Define acute

Cause adverse effect after one short-term exposure (formaldehyde). Effects are immediate

Define CDC

Centers for Disease Control

Who is most at risk of Indoor pesticide use/ IPM?

Children are most at risk

How can we reduce radon?

Close entry routes; cracks, drains, increase ventilation

What does the epiglottis do?

Closes off trachea during swallowing

What is the Chimney effect?

Contaminants drawn in due to pressure differences.

Describe The Amendments to Clean Air Act (1990).

Ended US production of CFC's CCl4, and methyl chloroform. Refrigerants can be collected and reused. New products (HFCs and HCFCs): less damaging to the ozone layer, but are more expensive.

What did the 1970 Clean Air Act do?

Established NAAQS and AQI

What is the major function of the human respiratory system?

Exchange gases with the environment.

Human health effects of VOCs (Volatile Organic Compounds)

Eye, nose, and throat irritation; headaches, loss of coordination, nausea; damage to liver, kidney, and central nervous system. Some organics can cause cancer in animals; some are suspected or known to cause cancer in humans. Key signs or symptoms associated with exposure to VOCs include conjunctival irritation, nose and throat discomfort, headache, allergic skin reaction, dyspnea, declines in serum cholinesterase levels, nausea, emesis, epistaxis, fatigue, dizziness.

What type of issue is outdoor air pollution now, and what are the major parts/problems?

Now a global issue (acid deposition, ozone depletion).

What is the formula for: O atoms combine with oxygen molecules?

O + O2 --> O3

Ozone produced

O2 + O = O

What is the formula for diatomic oxygen splitting?

O2 --> O + O

What is the formula for: Additional UV splits ozone into O2 and O, which recombines to form O3?

O3 --> O2 + O --> O3

Describe CFC's

Originally developed as a refrigerant, used in air conditioners, refrigerators. Non toxic, chemically stable, cheap. Other uses: aerosols, foams. No longer used for aerosols, still widely used as refrigerants.

Define Formaldehyde

Outgassed from furniture, drapes, upholstery, carpets, wallpaper

Where and when is the "Ozone Hole" Ozone depletion the most severe?

Over Antarctica, in Antarctic spring (Sept - Oct)

Environmental effects of ozone, smog

Ozone also affects sensitive vegetation and ecosystems, including forests, parks, wildlife refuges and wilderness areas. In particular, ozone harms sensitive vegetation, including forest trees and plants during the growing season. Visit the ecosystems page for more information.

Sources of ozone, smog

Ozone develops in the atmosphere from gases that come out of tailpipes, smokestacks and many other sources. When these gases come in contact with sunlight, they react and form ozone smog.

What is the worst OAP problem in Chapel Hill area?

Ozone in the summer

What happens when UV passes through the ozone layer?

Ozone is formed and destroyed

Why is indoor air pollution generally worse than outdoor air pollution?

People spend more time indoors. More concentrated indoors. HVAC systems encourage microbial growth. Air is recirculated, buildings are insulated.

Describe remediation of acid deposition

Periodic addition of lime to acidified lakes (costly)

What are the two types of smog?

Photochemical smog and Sulfurous smog

Why is the "Ozone Hole" ozone depletion the most severe at that time and place?

Polar vortex, air is isolated. Extreme cold forms polar stratospheric clouds, ties up Cl. Energy from spring sunlight releases Cl, starts destruction of O3.

What are secondary pollutants?

Pollutants that are modified after emission (acid deposition, smog - photochemical reaction activated by UV light).

What are primary pollutants?

Pollutants that are released directly into the air.

Precipitation is naturally ____

Precipitation is naturally acidic. (H2O + CO2 --> H2CO3)

What is acid rain?

Precipitation with pH < than naturally occurring rain (5.6)

How do cars contribute to air pollution?

Produce NOx, CO, previously Pb. Diesel source of PM.

How can we control air pollution?

Reduce automobile numbers and use. Stricter emissions standards and enforcement. Low emissions cars, improve gasoline, modify fuel. Public transportation, car pools. Catalytic converters, remove CO, NOx (cars only).

Where is peak ozone concentration?

30 km above the equator; 15 km above poles (12-18 miles)

How to control IAP

Reduce source (no smoking). Air filters, indoor plants, ventilation, exhaust. Clean and maintain HVAC, dehumidifiers

Environmental effects of particulate matter (PM)

Reduced visibility (haze). Increased acidity of lakes and streams. Nutrient balance changes in coastal waters and river basins. Reduced levels of nutrients in soil. Damage to forests and crops. Reduced diversity in ecosystems. Damage to stone and other materials

What does the National Emissions Standards for Hazardous Air Pollutants

Regulates emissions from point sources. For specific substances [air toxics HAPs with known or suspected serious health effects (mutagens, carcinogens, neurotoxins, teratogens)]. Tend to be localized, from point sources (ex. ammonia, chlorine, asbestos, arsenic, mercury, benzene).

What is the Stack effect?

Rising warm air replaced by cooler air from outside.

How long has outdoor air pollution been a regional problem?

Since the industrial revolution

How long has outdoor air pollution been a local problem?

Since the use of fire

What is smog?

Smoke + fog

Define ETS

Smoking is the most preventable cause of premature death in the US

What are CCl4, methyl chloroform, methyl bromide used in?

Solvents used in dry cleaning

How does industry contribute to air pollution?

Source of NOx, SOx, PM

What are non-point area sources?

Sources that can be broadly identified, but not specifically, (ex. cities).

What are point sources?

Sources that can be easily and exactly identified, (ex. power plants).

What are the two types of anthropogenic sources of OAP ?

Stationary (fixed) or mobile (cars, planes, ships)

Environmental effects of sulfur dioxide

Sulfur dioxide and nitrogen oxides are the major precursors of acid rain, which has acidified soils, lakes and streams, accelerated corrosion of buildings and monuments, and reduced visibility. Sulfur dioxide also is a major precursor of fine particulate soot, which poses a significant health threat.

What does burning release in sulfurous smog?

Sulfur oxides (SOx), mostly sulfur dioxide (SO2).

Define ambient

Surrounding

What happens when a number of occupants exhibit symptoms of IAP?

Symptoms disappear when they leave building

____ meant to ____ contributed to acid rain

Tall stacks meant to dilute pollution contributed to acid rain.

How do pollutants get in?

may originate in building. May enter through cracks, windows, doors, HVAC. Chimney effect. Stack effect.

Define UVC

wavelength = 0.28 - 0.1 micrometers, most energetic, absorbed in stratosphere, doesn't reach Earth's surface

Define UVA

wavelength = 0.4 - 0.32 micrometers; least energetic, not affected by stratospheric ozone

Describe photochemical smog

(LA type). from car emissions reacting with sunlight. Strong oxidants; harm respiratory system, damage crops and trees.

Describe sulfurous smog

(London type, gray air, industrial). From burning coal, oil.

Nitric oxide combines with O2 to form nitrogen dioxide

2NO + O2 = 2NO2

How can we reduce NOx?

Burn at lower temperatures

Define mortality

Death

Air quality is better in ____

The US

How does actual gas exchange occur?

Through diffusion

Define tidal volume

regular breathing (approximately 500 ml)

What do ozone depleting chemicals contain?

Either chlorine or bromine

What is the top ozone depleting substance?

Nitrous oxides

What type of ozone is good?

Stratosphere ozone

Define vital capacity

Total volume that can be exchanged

What type of reaction is ozone depletion?

A catalytic chain reaction

Define criteria

Based on scientific research

How does radon enter buildings?

Enters buildings through cracks, holes, well water or in bricks

What did Eastern Europe (Soviet Block countries) burn?

High S coal

What do the alveoli do?

Increase surface area for gas exchange

What does NAAQS stand for?

National Ambient Air Quality Standards

Equation of ozone depletion:

Cl + O3 --> ClO + O2 O3 + UV light --> O2 + O O + ClO --> Cl + O2 -------------------------------- Net: 2O3 --> 3O2

What are some sources of NOx?

Transportation (cars, trucks, buses)

What is Cl's role in ozone depletion?

Cl atom is a product and a reactant

What is OAP influenced by?

topography, meteorology, seasons (temperature inversions)

What are some anthropogenic sources of outdoor air pollution (in order)?

transportation, power plants, industry

Define UVB

wavelength = 0.32 - 0.28 micrometers; can cause damage, mostly absorbed by the ozone

Environmental effects of VOCs

A consequence of the uncontrolled emission of VOCs, in general, and solvents, in particular, is that they may act as greenhouse gases and hence there may be climate change consequences.

What are average stratospheric ozone levels?

About 300 DU

Acid rain is caused by emissions of ___ and ___ converted into ___ and ___

Acid rain is caused by emissions of SO2 and NOx converted into H2SO4 and HNO3.

What did the 1990 amendments to the Clean Air Act add provisions for?

Acid rain, urban smog, HAPs, ozone protection, and CFCs, and trade allowances for SOx

Human health effects of outdoor air pollution.

Acute: irritation of eyes, skin, and respiratory system. Aggravates asthma and emphysema (COPD), contributes to CV disease. Increases susceptibility to respiratory infection (pneumonia, bronchitis). Chronic: permanently decreases lung function, raises risk of lung cancer.

What are the effects of acid deposition in aquatic ecosystems?

Affects fish, amphibians, arthropods

What are some environmental effects of outdoor air pollution?

Affects plant growth (productivity), crop yields, and disrupts food web. Acidification of aquatic ecosystems, eutrophication. Decreases visibility and clarity.

What does AQI stand for?

Air Quality Index

What respiratory problems are affected by air pollution?

Asthma, chronic bronchitis, lung cancer, emphysema

Human health effects of carbon monoxide

At low concentrations, fatigue in healthy people and chest pain in people with heart disease. At higher concentrations, impaired vision and coordination; headaches; dizziness; confusion; nausea. Can cause flu-like symptoms that clear up after leaving home. Fatal at very high concentrations. Acute effects are due to the formation of carboxyhemoglobin in the blood, which inhibits oxygen intake. At moderate concentrations, angina, impaired vision, and reduced brain function may result. At higher concentrations, CO exposure can be fatal.

Sources of lead (Pb)

At the national level, major sources of lead in the air are ore and metals processing and piston-engine aircraft operating on leaded aviation fuel. Other sources are waste incinerators, utilities, and lead-acid battery manufacturers. The highest air concentrations of lead are usually found near lead smelters.

What is the average indoor level of radon?

Average indoor level = 1.3 pCi/L, average outdoor level = 0.4 pCi/L, EPA "action level" is 4.0 pCi/L,

Define Legionnaire's Disease

Bacteria spread through HVAC system (American Legion Convention in Philidelphia)

Why doesn't the AQI measure levels of Pb?

Because it's not as much of a concern because it's not in anything that is currently being manufactured (not in gas, paint, etc. anymore).

Why are children especially affected by outdoor air pollution?

Because their immune systems aren't fully developed yet; they have a lower VC; weak system; they're smaller than adults, so a smaller concentration of pollution is able to affect them more drastically.

Why are amphibians and lichens good indicator species?

Because they are especially sensitive , so they react quicker to changes in the environment.

Human health effects of ozone, smog

Breathing ozone can trigger a variety of health problems including chest pain, coughing, throat irritation, and congestion. It can worsen bronchitis, emphysema, and asthma. Ground level ozone also can reduce lung function and inflame the linings of the lungs. Repeated exposure may permanently scar lung tissue.

What causes the most damage to the ozone?

CFC's (chlorofluorocarbons/"Freon")

How can we use technology to reduce SOx?

Ca reacts with sulfur to form calcium sulfate (CaSO3)

How does acid deposition harm humans?

Can harm human health (respiratory system), damage buildings

What are the human health effects of ozone loss?

Cataracts, increased incidence of skin cancers, weakened immune systems

What are the categories of AQI and what do they mean?

Green = good. Yellow = moderate. Orange = unhealthy for sensitive groups. Red = unhealthy. Purple = very unhealthy.

What type of ozone is bad?

Ground level ozone

What are some sources of indoor air pollution?

HVAC - Bacteria and molds. Insulation - asbestos, fiberglass fibers. Pesticides. Treated lumber, carpets - formaldehyde. Tobacco smoke - ETS. Faulty furnaces -CO. Radon gas. Paint, solvents, cleaning products - VOCs.

What are some symptoms of IAP?

Headache, dizziness, nausea, fatigue. Skin, eye, throat irritation, rash. Sinus congestion, shortness of breath, coughing, sneezing. Acute vs chronic effects. Some persons are more sensitive than others.

Sources of VOCs (Volatile Organic Compounds)

Household products including: paints, paint strippers, and other solvents; wood preservatives; aerosol sprays; cleansers and disinfectants; moth repellents and air fresheners; stored fuels and automotive products; hobby supplies; dry-cleaned clothing.

Define morbidity

Illness or disease

In 2011, the EPA began ___ under the ___, this is still ____

In 2011, the EPA began regulating greenhouse gases under the CAA, this is still under heavy debate.

Where are some Radon hotspots?

In PA, NJ, NY. Also in NC mountains.

Human health effects of lead (Pb)

In addition to exposure to lead in air, other major exposure pathways include ingestion of lead in drinking water and lead-contaminated food as well as incidental ingestion of lead-contaminated soil and dust. Lead-based paint remains a major exposure pathway in older homes. Learn more about lead in paint, dust and soil.

What are the effects of ozone loss caused by?

Increased UV radiation reaching Earth

How can we use trade allowances to reduce SOx?

Market based system to encourage reduction in SO2

Sources of sulfur dioxide

Industrial activity that processes materials that contain sulfur (ex. generation of electricity from coal, oil or gas that contains sulfur). Some mineral ores also contain sulfur, and sulfur dioxide is released when they are processed. Industrial activities that burn fossil fuels containing sulfur can be important sources of sulfur dioxide. Present in motor vehicle emissions, as the result of fuel combustion (not as big of a problem now).

Define Radon

Inert, radioactive gas, breakdown product of uranium

What are the environmental effects of ozone loss?

Interferes with photosynthesis, lowers productivity, less food available to food web, results in lower crop yields, lowers productivity of phytoplankton, disrupts marine food webs

Human health effects of sulfur dioxide

Irritates the nose, throat, and airways to cause coughing, wheezing, shortness of breath, or a tight feeling around the chest. The effects of sulfur dioxide are felt very quickly. Those most at risk of developing problems if they are exposed to sulfur dioxide are people with asthma or similar conditions.

Human health effects of particulate matter (PM)

Irritation of the airways, coughing, and difficulty breathing. Reduced lung function. Aggravated asthma. Chronic bronchitis. Irregular heartbeat. Nonfatal heart attacks. Some cancers

What does the NAAQS do?

It sets acceptable concentrations for 6 "criteria" pollutants. These pollutants - 1) Threaten public health/the environment over board areas (non-point). 2) Are emitted in large quantities. 3) CO, Pb, Nitrogen oxides NOx, Ozone, Particulate matter, SOx.

Radon is a breakdown product of a radioactive element. What are some of the human health effects of radon?

Lung cancer, radiation poisoning/sickness, reduced lung capacity, shortness of breath.

How is radon measured?

Measured in pCi/L(picocuries per liter)

What does AQI do?

Measures levels of 5 criteria pollutants. Forecast of daily air pollution levels. Purpose to educate and protect public - focuses on health effects. Limitations - doesn't cover chronic or synergistic effects.

Define spirometer

Measures respiratory function

__, ___ air exceed WHO standards ___

Mexico City, Beijing: air exceeds WHO standards 350 days/year.

Define asbestos

Mineral used as building material, flame retardant

How can we use limestone injection to reduce SOx?

Mix coal with limestone before burning

Define Sick Building Syndrome

More common in newer buildings; unhealthy indoor environment.

Where is sulfurous smog mostly located?

Mostly in stagnant air, cloud cover, high humidity

Burning forms nitric oxide

N2 + O2 = 2NO

Does precipitation always have to be wet?

NO - can be rain, snow, sleet, fog, dew, or acid particles

Nitrogen oxide breaks down

NO2 + UV radiation = NO + O

Environmental effects of nitrogen oxides

NOx and sulfur dioxide react with other substances in the air to form acids, which fall to earth as rain, fog, snow or dry particles. Additional nitrogen accelerates "eutrophication," which leads to oxygen depletion and reduces fish and shellfish populations. One member of the NOx, nitrous oxide, is a greenhouse gas. It accumulates in the atmosphere with other greenhouse gasses causing a gradual rise in the earth's temperature.

What is NOx, and what is its major source?

Nitrogen oxides, especially from jet contrails

Sources of nitrogen oxides

Nitrous oxide is emitted when people add nitrogen to the soil through the use of synthetic fertilizers. Agricultural soil management is the largest source of N2O emissions in the United States. Nitrous oxide is emitted when transportation fuels are burned. Nitrous oxide is generated as a byproduct during the production of nitric acid, which is used to make synthetic commercial fertilizer, and in the production of adipic acid, which is used to make fibers, like nylon, and other synthetic products. Nitrous oxide emissions occur naturally through many sources associated with the nitrogen cycle.

What areas are most affected by acid deposition?

Northeast US, Canada, Scandinavia

What happened in Donora, Pa in 1948?

The 1948 Donora smog was a historic air inversion resulting in a wall of smog that killed 20 people and sickened 7,000. Hydrogen fluoride and sulfur dioxide emissions from U.S. Steel's Donora Zinc Works and its American Steel & Wire plant were frequent occurrences in Donora. What made the 1948 event more severe was a temperature inversion, a situation in which warmer air aloft traps pollution in a layer of colder air near the surface.

What happened in London, England in 1952?

The Great Smog of '52 or Big Smoke[1] was a severe air-pollution event that affected London during December 1952. A period of cold weather, combined with an anticyclone and windless conditions, collected airborne pollutants mostly from the use of coal to form a thick layer of smog over the city. It is known to be the worst air-pollution event in the history of the United Kingdom,[3] and the most significant in terms of its effect on environmental research, government regulation, and public awareness of the relationship between air quality and health.[2] It led to several changes in practices and regulations, including the Clean Air Act 1956.

If prevailing winds are responsible to transporting the ingredients for acid rain, what part of the country would have the worst effects?

The Northeast would have the worst effect

What causes the expansion of the lungs?

The diaphragm and the rib muscles

Where is ozone concentration thinnest?

The equator

What are the major organs of the human respiratory system?

The lungs

What purpose does the ozone layer serve for life on land?

The ozone shields life on land from damaging UV radiation

Where is the hole in the ozone layer?

The poles

The resulting acid rain can be carried ____ by ___

The resulting acid rain can be carried long distances by prevailing winds.

Simplified chemistry of ozone depletion explanation:

The same UV radiation that drives ozone formation/destruction breaks apart CFCs and releases Cl atoms.

Sources of particulate matter (PM)

There are many sources of PM. The air pollutant can originate from natural processes, like forest fires and wind erosion, and from human activities, like agricultural practices, smokestacks, car emissions, and construction. Examples include dust, dirt, soot, soil, and smoke.

How have further revisions been perceived by industries and environmentalists?

They have been challenged

How often does the process of ozone being formed/destroyed occur?

This process occurs constantly, and absorbs UV radiation

Of the three types of UV emissions, which one do we need to worry about the most? Why?

UVB, because this is the type of radiation that would normally be filtered by ozone, but that is now reaching the surface of the Earth in significant quantities.

Sources of carbon monoxide

Unvented kerosene and gas space heaters; leaking chimneys and furnaces; back-drafting from furnaces, gas water heaters, wood stoves, and fireplaces; gas stoves; generators and other gasoline powered equipment; automobile exhaust from attached garages; and tobacco smoke. Incomplete oxidation during combustion in gas ranges and unvented gas or kerosene heaters may cause high concentrations of CO in indoor air. Worn or poorly adjusted and maintained combustion devices (e.g., boilers, furnaces) can be significant sources, or if the flue is improperly sized, blocked, disconnected, or is leaking. Auto, truck, or bus exhaust from attached garages, nearby roads, or parking areas can also be a source.

What did the New Source Review require older industries and refineries to do?

Upgrade their pollution controls if they are going to modify their facilities.

Where is OAP the worst?

Urban and industrialized areas

Who do synergistic effects mostly affect?

Urban dwellers, some occupations like miners and textile workers.

How to reduce PM

Use bag filters, electrostatic precipitators, ash must be landfilled.

How to lower SOx

Use low sulfur, alternative energy, improve conservation, efficiency. Fluidize bed combustion.

What are Halons?

Used in fire extinguishers, refrigerants, and foams

What are some natural sources of outdoor air pollution?

Volcanoes, pollen, microorganisms, dust storms, wildfires.

Define WHO

World Health Organization

Where is sulfurous smog the worst?

Worse in less developed countries with inadequate pollution control.

What is the worst problem in less developed countries?

Worst problem in LDC is particulate matter from burning biomass

Can a Cl atom be used over?

Yes

What are some sources of SO2?

coal powered plants, industrial plants

What did the burning of high S coal in Eastern Europe result in?

forest decline due to acid rain, major human health problems