Air Pollution By: Sarah Kreps

Air Pollution is the most widespread and obvious kind of pollution.

147 million metric tons of air pollution (excluding CO2 and wind blown dust and soil) are released into the air from human activity alone in the United States

Over 2 billion metric tons are released worldwide.

Pollutes is a Latin word meaning, to make foul, unclean, or dirty.

Air Pollutants can come from natural sourcesvolcanoes sea spraydecaying vegetation

However in many cities 90% of air pollution is (anthropogenic) human produced.

Human Caused Pollutants

Primary pollutants- pollutants released directly from the source into the air, already in a harmful form

Secondary pollutants- modified to a hazardous form after they enter the air, formed by chemical reactions as components of the air interact. solar radiation provides the energy that powers the reactions.

Fugitive emissions- pollutions that do not come through a smoke stack. ex. Strip mining, rock crushing, and construction building

Clean Air Act of 1970’s- designated seven major pollutants (sulfur dioxide, carbon monoxide, particulates, hydrocarbons, nitrogen oxide, photochemical oxidants, and lead) for which maximum ambient air- the air around us levels are mandated.

The seven pollutants are criteria pollutants and contribute the largest volume of air-quality duration and threat to human welfare and health.

Sulfur CompoundsNatural sources of sulfur come from evaporation of sea water,

erosion of sulfate-containing dust, and fumes from volcano eruptions.

114 million metric tons of sulfur is released yearly into the atmosphere.

Human sources of sulfur comes from the burning of coal and oil, the purification of gasses and oils, and industrial process.

China and the United States are the largest sources of anthropogenic (human caused) sulfur pollution

Sulfur dioxide- is a colorless corrosive gas that is directly damaging to both plants and animals. When it reacts with water droplets in the atmosphere it can form sulfuric acid, a major component in acid rain.

Nitrogen CompoundsNitrogen oxides- highly reactive gasses formed

when nitrogen in fuel or combustion air is heated to temperatures above 650 degrees Celsius, in the presences of oxygen, or when bacteria in soil or water oxidize nitrogen-containing compounds.

Emissions for nitrogen oxides is around 230 million metric dons worldwide.

Extra nitrogen causes excessive fertilization and encouraging growth of weedy species that crowd out native varieties.

Carbon OxidesThe predominate form of carbon in the air is carbon dioxide.Steady increasing about .5 percent in the atmosphere due to human

activities. Carbon Oxides are playing a major role in the global climate warming that could potential had disastrous effects.

90% of CO2 released each year is from respiration, and is usually converted into oxygen through photosynthesis.

Human caused CO2 pollution is estimated at 7-8 billion metric tons of carbon by the burning of fossil fuels.

Carbon monoxide- is a colorless, odorless, and nonirritating but highly toxic gas produced by incomplete combustion of fuel, incineration of biomass or solid waste, or partially anaerobic decomposition of organic materials. 1 billion metric tons of CO is released annually (1/2 is from human activities)

Particle MaterialAerosol- is any system of solid particles or liquid

droplets suspended in gaseous medium, often described as particulate material.

These include dust, ash, soot, lint, smoke, pollen, spores, algal cells, and other suspended materials.

Anthropogenic particle emissions is about 362 million metric tons per year worldwide.

Metals and HalogensMany toxic metals are used and mined in the

manufacturing process or occur as trace elements in fuels, especially coal.

These metals are released to the air in the form of metal fumes or suspended particles by fuel combustion, ore smelting, and disposal of waste.

Lead in gasoline caused huge human health effects as well as environmental. By banning lead in gas pollution was significantly cut down, and children's IQ’s were higher and lead in their blood was lower.

Volatile Organic CompoundsVolatile Organic Compounds- are organic chemicals that

exist as gases in the air.Plants are the largest source of VOC’s releasing 350

million metric tons of isoprene and 450 million metric tons of terpenes each year.

400 million metric tons of methane are released through natural wetlands, rice paddies, and by bacteria in the guts of termites and ruminant animals.

28 million metric tons are emitted through human activities, most from burning hydrocarbons from transportation, power plants, chemical plans, and petroleum refineries.

Photochemical OxidantsPhotochemical Oxidants- are products of secondary

atmospheric reactions driven by solar energy. One of the single most important reaction is the

formation of the singlet (atomic)oxygen by splitting nitrogen dioxide.

This creates atomic oxygen then reacts with another molecule of O2 to make ozone.

Ozone- formed in the stratosphere provides a valuable shield for the biosphere by absorbing incoming ultraviolent radiation.

Air ToxinsHazardous air pollutants (HAP’s)- toxins monitored by

the EPA because they are especially dangerous. They include, carcinogens, neurotoxins, mutagens, teratogens, and endocrine disrupters, most of which are persistent bioaccumulation toxic chemicals.

Most of these compounds are metal compounds, chlorinated hydrocarbons, or volatile organic compounds.

Toxic Release Inventory- collected by the EPA it is a collection of a report on the toxins given off by factories and industrial plants all over the United States.

Aesthetic degrations- includes any undesirable changes in the physical characteristics or chemistry of the atmosphere.

Noise, odors, and light pollution are examples of atmospheric degradation that may not be live threatening but reduce the quality of our lives.

Indoor PollutionIndoor contaminates can some time be

just as dangerous if not more dangerous then pollutants outside.

Smoking is the most important air pollution, it kills of 400,000 people each year.

Total cost for early deaths and smoking-related illnesses in the United States are world 100billion dollars annually

Temperature inversions trap Pollutants

Temperature inversions- occur when a stable layer of warmer air overlays cooler air, reversing the normal temperature decline with increasing height and preventing convection currents from dispersing pollutants.

the most stable inversions and photochemical smog can be observed in Los Angles.

Cities create dust domes and heat islands

Sparse vegetation and high levels of concrete and glass in urban areas allow rainfall to run off quickly and create high rates of heat absorption during the day and radiation at night.

Tall buildings create convective updraft that sweep pollutants into the air.

Temperature in large cities are a couple degrees warmer then the area surrounding it.

Causing a “heat island”

Wind Currents Cary Pollutants

Dust and contaminants can be carried great distances by the wind.

Areas down from industrial areas have serious contaminants, even if they have so source of pollution themselves.

70% of the mercury that fall of the United States is from Asia.

Asians pollution problems as grown so bad that they now have a “brown cloud” that blocks sunlight and disrupts the El Nino/ Southern Oscillation patters in the Pacific Ocean

Stratospheric ozone- levels over the south pole were dropping precipitation during September and October every year as the sun reappears at the end of the long polar winter.

This ozone depletion had been occurring at least since the 1960’s but was not recognized because earlier researchers programmed their instruments to ignore changes in the ozone levels that were presumed to be erroneous.

Chlorofluorocarbons- and other halogen gases are the principal agents of ozone depletion.

5 to 6 million people a year die prematurely from an illness related to air pollution such as heart diseases, and repertory complications

15 to 17 percent more likely if you live in a polluted city to develop one of these illnesses

Suffering ill health from air pollutants depends on the intensity and duration of the of the exposure

The United Nations estimates that 1.3 billion people around the world live in areas where the outdoor air is dangerously polluted.

2 million children under the age of 5 die from acute repertory diseases worsened by air pollution

Particulate material in the air can lead to:heart attacks, asthma, bronchitis, lung cancer, immune suppression, and abnormal fetal development.

Diesel engines remain the biggest unregulated producers of soot in the united states.

The most common route of exposure for air pollutants is by inhalation, but direct absorption through the skin or contamination of food and water are also important

Breathing in these chemicals can lead to…Bronchitis- a persistent inflammation of bronchi and

bronchioles that cause mucus buildup, a painful cough, and involuntary muscle spasms that constrict airways

Chronic obstructive lung disease- airways become permanently constricted and alveoli are damaged or destroyed.

Irritants in the air are so widespread that half of all lungs examined at autopsy in the US have some degree of alveolar deteriation.

Two ways air pollution damages plants1) Directly toxic, damage sensitive cell

membranes, discoloration, dead spots, and if strong enough the whole plant could die.

2) Low pollutant levels will show smaller yields of crops that are more sensitive such as soy beans.

Acid precipitation- the deposition of wet acidic solutions or dry acidic partials from the air.

Normal water has an acidity of 5.6 pH while acid rain water is well below that.

Aquatic effectsAir pollution in the atmosphere and in the form of acid rain strongly effects

aquatic life.Eggs and Fry of fish are easily killed when the pH in their body of water

changes the slightest bit.Lakes at high altitude have no fish because the acidity of the water is way to

high to support life because of the acid rain.Forest damageRapid decline of forest in North America and Europe can be traced to acid rain.Forest that are above 6,000 feet are beginning to lose there needles, and the

tree density. Forest in Europe have become depleted of natural buffering reserves of basic cations such as calcium and magnesium in there soil.

Buildings and MonumentsOld sculptures and monuments are being destroyed by the strong acidity and

defects of acid rain.Limestone and marble are easily broken down by the rain. And the Parthenon

in Athens and Coliseum are slowly dissolving away.

Pollution affect rural areas as well as cities. Even national parks suffer from air pollution. Visibility has suffered, at the grand canyon visibility use to be around 300km and now is only 20 km.

Human Pollution has cause a “haze blob” that spreads over 3,000km of the eastern United States

If all operations shut down for a couple of day visibility would improve from 15 km to 150km.

Air Pollution Control

Particulate removal- can be used to filter emisions These can be up to 99% efficient in removing partialsSulfur removal- is the most important because it has become

the most damaging to human health.Switching from high sulfur coal to low sulfur coal is an easy

way to reduce emissions. Nitrogen oxides- can be reduced in both internal combustion

engines and industrial boilers as much as 50% by carefully controlling the flow of air and fuel

Hydrocarbon controls -mainly involve complete combustion or controlling evaporation.

Alternative energy-solar wind

Legislation

Clean Air Act was the first national legislation to control air pollution in the United States. provided federal loans to combat pollution in individual states.

It is intended to monitor human health effects of pollution as well.

Cap and trade- lets facilities facing coasty cleanup bills to pay others with lower costs to reduce the emissions on their behalf, it has worked effectively for sulfur dioxide.

In 1980’s 97 areas did not meat regulations for air pollution now the number has dropped significantly to 41.

In the developing world air pollution is one the rise and will become even a more prominent threat over the next couple of years.

As areas in the third world become more industrialized there air pollution will rise as well.