Air Pollution Prepared by : Kholoud Thiab Dr : Raed Al Kowni.

Air PollutionPrepared by : Kholoud Thiab

Dr : Raed Al Kowni

Content-Atmosphere.

-Atmosphere layers.

-Air pollution.

-Major categories of air pollution sources.

-Effects of air pollution.

-Air Pollution & Health.

-The major air pollutants.

-Acid rain.

-Air toxics.

-Indoor air pollution.

-Control of air pollution.

-The atmosphere is a complex natural gaseous system (78% nitrogen and 21% oxygen with traces of water vapor, carbon dioxide, argon, and various other components) surrounding the planet Earth essential to support life on planet by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variation).

Atmosphere layers: -Exosphere

-Thermosphere

-Mesosphere

-Stratosphere : ozone layer

-Troposphere.

-Stratospheric ozone depletion due to air pollution has been recognized as a threat to human health as well as to the Earth's ecosystems.

-Air pollution is the introduction of particulates, biological molecules, or other harmful materials into

the Earth's atmosphere, possibly causing disease, death to humans, damage to other living organisms

such as food crops, or the natural or built environment.

Major categories of air pollution sources1 -stationary sources include:

-point sources :emit pollution from controllable site.

-fugitive sources :generate air pollution from open area exposed to wind.

-area sources :area which had several sources of pollutants.

2 -mobile sources include:

Automobile, trucks, buses, ships, air craft and any thing pollute air and moves from place to place.

Effects of air pollution

Air pollution affect of many aspect of our

environment include visual qualities, vegetation,

animals, soils, water quality, natural and

artificial structures and human health .

Air Pollution & Health

-Lung Function , Lung Growth, Lung disease

-Inflammatory Markers

- Blood Viscosity & Irregularities in Heartbeats

- Pulmonary Deaths

- Cardiovascular Deaths

-Mortality

-Cardiovascular disease

-Cystic fibrosis

-Cancer

The major air pollutants

*Primary pollutant :emitted directly into the air .they

include particulates, carbon monoxide, sulfur dioxide,

nitrogen oxides and hydrocarbons.

*Secondary pollutant :produced from reaction between

primary pollutant and normal atmosphere compound .such

as ozone forms over urban area through reaction of primary

pollutants, sunlight and natural atmosphere gases .

Primary Pollutant

-Sulfur oxides (SOx) : colorless, odorless gas, produced by

volcanoes and in various industrial processes. Coal and

petroleum often contain sulfur compounds, and their combustion

generates sulfur dioxide. SO4 combines with water to form acid

rain ,toxic to plants and animals.

- Nitrogen oxides (NOx) ,nitrogen dioxide, and nitric oxide: yellow

brown to reddish gas . Nox converted to nitrates in atmosphere causing

acid rain . expelled from high temperature combustion, and are also

produced during thunderstorms by electric discharge.

-Carbon monoxide (CO) : colorless, odorless, toxic.9o%

natural 10%from incomplete combustion of fuel and

cigarettes . Vehicular exhaust is a major source of carbon

monoxide.

Combines with hemoglobin in blood →reduce ability to

carry oxygen.

.

-methane (CH4): is an extremely efficient greenhouse

gas which contributes to enhanced global warming .

-non-methane (NMVOCs) : benzene, toluene and

xylene are suspected carcinogens and may lead to

leukemia with prolonged exposure. 1,3-butadiene is

another dangerous compound often associated with

industrial use.

particulate matter (PM) : tiny particles of solid or liquid

suspended in a gas. Some particulates occur naturally,

originating from volcanoes, dust storms, forest and grassland

fires, living vegetation, and sea spray. Human activities, such

as the burning of fossil fuels in vehicles, power plants and

various industrial processes also generate significant amounts

of aerosols. Increased levels of fine particles in the air are

linked to health hazards such as heart disease, altered lung

function and lung cancer.

Ammonia (NH3) - emitted from agricultural processes. It is

normally encountered as a gas with a characteristic pungent

odor. Ammonia contributes significantly to the nutritional

needs of terrestrial organisms by serving as a precursor to

foodstuffs and fertilizers.it is also a building block for the

synthesis of many pharmaceuticals. Although in wide use,

ammonia is both caustic and hazardous. In the atmosphere,

ammonia reacts with oxides of nitrogen and sulfur to form

secondary particles.

Lead : exposure to lead occurs through inhalation air and ingestion of

lead in food, water, soil or dust.

It accumulates in blood, bone and soft tissue and can adversely affect

kidney, liver, nervous system and other organs.

*Excessive exposure to lead cause:

-Neurological impairment such as seizures, Mental retardation and

behavioral disorders.

*Recent studies indicated that lead may be factor in high blood pressure

and heart disease.

*Lead deposited on leaves of plants presented a hazard to grazing animal

and to human through ingestion.

Secondary pollutants

ozone (O3) : is a key constituent of the troposphere, highly

poisonous gas with strong odor.

*Breathing O3 Irritates Airways affect respiratory and nervous

systems.

*O3damage plants → leaf mottling and reduce growth.

-Photochemical oxidant : arising from atmospheric

interaction of nitrogen dioxide and sunlight .

Formation of ozone

Symptoms

-Cough

–Sore or scratchy throat

–Pain with deep breath, or chest pain

–Fatigue

Ozone Causes Inflammation

•Ozone reacts completely in surface layer

•Forms reactive oxygen molecules

•Influx of white blood cells – neutrophils, eosinophils

•Damages cells that line the airway

•Effect is greater 24 hours after exposure

Acid rain

is a rain or any other form of precipitation that is unusually acidic,

meaning that it possesses elevated levels of hydrogen ions (low pH ≤

5.6). It can have harmful effects on plants, aquatic animals and in forest.

Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide,

which react with the water molecules in the atmosphere to produce

acids .

H2O (l) + CO2 (g) is in equilibrium with H2CO3 (aq)

H2O (l) + H2CO3 (aq) is in equilibrium with HCO3− (aq) + H3O+ (aq)

Combustion of fuels produces sulfur dioxide and nitric

oxides. They are converted into sulfuric acid and nitric

acid.

SO2 + OH· → HOSO2·

HOSO2· + O2 → HO2· + SO3

SO3 (g) + H2O (l) → H2SO4 (aq)

Acid rain

Adverse effects

Surface waters and aquatic animals : damage fish and other

aquatic animals. biodiversity is reduced.

Soils : Soil biology and chemistry can be seriously damaged by

acid rain. Some microbes are unable to tolerate changes to low

pH and are killed . The enzymes of these microbes are

denatured (changed in shape so they no longer function) by the

acid .

.

Human society : Acid rain can damage buildings, historic

monuments, and statues, especially those made of rocks, such as

limestone and marble, that contain large amounts of calcium

carbonate. Acids in the rain react with the calcium compounds

in the stones to create gypsum, which then flakes off.

Forest ecosystem : slowed tree growth, leaves turn brown and

fall off, death of trees.

Air toxics

Air toxics include gases, metals and organic chemicals that are

emitted in relatively small volume (example: benzene).

They cause respiratory, neurological, reproductive and immune

disease and may be carcinogenic

The effect on individual health depend on:

-duration and frequency of exposure.

-toxicity of chemicals.

-concentration of pollutant.

-mode of exposure.

Indoor air pollution

-The pollution com from our homes, schools and other

building that we are spend time in it.

-Formaldehyde is the major cause of indoor air

pollution.

Sources of indoor air pollution

-building materials.

-cigarette smoking.

-pesticides.

-Volatile organic from paints, furniture, rugs, insulation.

Symptoms of indoor air pollution

-irritation of mucous membrane.

-coughing.

-dizziness.

-nausea.

-death.

Solution to indoor air pollution

-use ventilation system.

-Source removal: no smoking.

-Source modification: more efficient stove design.

-Pollutant removal: filters.

-Education.

-Designing building to minimize indoor air pollution.

Control of air pollution

-planting more trees.

-reducing vehicle exhausts.

-using less polluting fuels.

-removal of particulate matter using electrostatic precipitator,

cyclone filter.

-industrial area should be cited far away from residential area.