Air pollution: its causes,effects and pollutants

Preview:

Citation preview

14.3: Air Pollutants

14.3.1: list major air pollutants;14.3.2: describe sources and explain

effects of air pollutants;14.3.3: describe how incineration of waste material contributes to

the problem of airpollution giving examples from

daily life;14.3.4: suggest what the government

should do more to control air pollution resulting

from auto exhaust;

Air

Air is the Earth's atmosphere. It is the clear gas in which living things live and breathe. It has an indefinite shape and volume. It has no color or smell. It has mass and weight. It is a matter as it has mass and weight. Air creates atmosphere pressure.

14.3.1: list major air pollutants;

What is air pollutants?• A substance in the air that can

cause harm to humans and the environment is known as an air pollutant. Pollutants can be in the form of solid particles, liquid droplets, or gases. In addition, they may be natural or man-made.

Six major air pollutants

• Carbon monoxide (CO)• Ozone (O3)• Nitrogen dioxide (NO2)• Sulfur oxides (SOx)• Carbon dioxide (CO2 )• Lead (Pb)

Major sources of pollutants

14.3.2: describe sources and

explain effects of air pollutants;

There are two types of pollutants:

Primary pollutantsSecondary pollutants

Primary pollutants:  Primary pollutants are those gases or particles that are pumped into the air to make it unclean. They include carbon monoxide from automobile (cars) exhausts and sulfur dioxide from the combustion of coal. Primarily air pollutants can be caused by primary sources or secondary sources. The pollutants that are a direct result of the process can be called primary pollutants. A classic example of a primary pollutant would be the sulfur-dioxide emitted from factories

• SOME PRIMARY

POLLUTANTS…………….

CARBON MONOXIDE (CO)

Nitrogen Dioxide

•reddish, brown gas•produced when nitric oxide combines with oxygen in the atmosphere•present in car exhaust and power plants•affects lungs and causes wheezing; increases chance of respiratory infection

NITROGEN DIOXIDE (N02)

SULPHUR DIOXIDE (S02) 

GREEN HOUSE GASES

Carbon Dioxide•Carbon dioxide, a greenhouse gas, is the main pollutant that is warming Earth. Though living things emit carbon dioxide when they breathe, carbon dioxide is widely considered to be a pollutant when associated with cars, planes, power plants, and other human activities that involve the burning of fossil fuels such as gasoline and natural gas. In the past 150 years, such activities have pumped enough carbon dioxide into the atmosphere to raise its levels higher than they have been for hundreds of thousands of years.

Chlorofluorocarbons (CFCs)

PARTICULATE MATTER

Secondary pollutants: 

When pollutants in the air mix up in a chemical reaction, they form an even more dangerous chemical. Photochemical smog is an example of this, and is a secondary pollutant. Secondary pollutants are the ones that are caused by the inter mingling and reactions of primary pollutants. Smog created by the interactions of several primary pollutants is known to be as secondary pollutant.

SOME SECONDARY AIR

POLLUTANTS…………………

GROUND LEVEL OZONE

SMOG

Smog is caused when car emissions and industrial pollution interact with sunlight. Smog is often

caused by heavy traffic, high temperatures, sunshine and calm winds. These are few of the factors behind increasing

level of air pollution in atmosphere. During the

winter months when the wind speeds are low, it helps the smoke and fog to become

stagnate at a place forming smog and increasing pollution levels near the ground closer to where people are respiring.

It hampers visibility and disturbs the environment. The

atmospheric pollutants or gases that form smog are

released in the air when fuels are burnt. When sunlight and

its heat react with these gases and fine particles in the atmosphere, smog is formed.

SMOG. Smog is another common secondary pollutant. Smog is a yellowish or blackish fog formed mainly by a mixture of pollutants in the atmosphere which consists of fine particles and ground level ozone. Smog which occurs mainly because of air pollution, can also be defined as a mixture of various gases with dust and water vapor. Smog also refers to hazy air that makes breathing difficult.

POLLUTANT SOURCES EFFECTS

Smog affects plant life and the health of animals and humans. It is harmful to humans, animals, plants and the nature as a whole. Smog lead to bronchial diseases.Heavy smog results in a low production of the crucial natural element vitamin D leading to cases of rickets among people. Smog can be responsible for any ailment from minor pains to deadly pulmonary diseases such as lung cancer. Smog is well known for causing irritation in the eye. It may also result in inflammation in the tissues of lungs; giving rise to pain in the chest. Other issues or illnesses such as cold and pneumonia are also related to smog. The human body faces great difficulty in defending itself against the harmful effects of smog.

SMOG

FORMATION OF SMOG

EFFECTS OF SMOG

Any visible or invisible particle or gas found in the air that is not part of the original, normal composition.

Air pollution occurs when gases, dust particles, fumes (or smoke) or odor are introduced into the atmosphere in a way that makes it harmful to humans, animals and plant. This is because the air becomes dirty (contaminated or unclean). 

The Earth is surrounded by a blanket of air (made up of various gases) called the atmosphere. The atmosphere helps protect the Earth and allow life to exist. Without it, we would be burned by the intense heat of the sun during the day or frozen by the very low temperatures at night

.Anything additional gas, particles or odors that are introduced into the air (either by nature or human activity) to destroy this natural balance can be called air pollution.Things that pollute the air are called pollutants. Examples of pollutants include nitrogen oxides, carbon monoxides, hydrocarbons, sulphur oxides (usually from factories), sand or dust particles, and organic compounds that can evaporate and enter the atmosphere.

Causes Of Air Pollution

What causes air pollution?Air pollution can result from both human and natural actions. Natural events that pollute the air include forest fires, volcanic eruptions, wind erosion, pollen dispersal, evaporation of organic compounds and natural radioactivity. Pollution from natural occurrences are not very often.

Human activities that result in air pollution include:1. Emissions from industries and manufacturing activitiesHave you seen a manufacturing company before? You will notice that there are long tubes (called chimneys) erected high into the air, with lots of smoke and fumes coming out of it. Waste incinerators, manufacturing industries and power plants emit high levels of carbon monoxide, organic compounds, and chemicals into the air. This happens almost everywhere that people live. Petroleum refineries also release lots of hydrocarbons into the air.

INDUSTRIAL EMISSION

2. Burning Fossil FuelsAfter the industrial age, transportation has become a key part of our lives. Cars and heavy duty trucks, trains, shipping vessels and airplanes all burn lots of fossil fuels to work. Emissions from automobile engines contain both primary and secondary pollutants. This is a major cause of pollution, and one that is very difficult to manage. This is because humans rely heavily on vehicles and engines for transporting people, good and services.

Fumes from car exhaust contain dangerous gases such as carbon monoxide, oxides of nitrogen, hydrocarbons and particulates. On their own, they cause great harm to people who breath them. Additionally, they react with environmental gases to create further toxic gases.

BURNING FOSSIL FUELS

3.Agricultural activities:Ammonia is a very common by product from agriculture related activities and is one of the most hazardous gases in the atmosphere. Use of insecticides, pesticides and fertilizers in agricultural activities has grown quite a lot. They emit harmful chemicals into the air and can also cause water pollution.

AGRICULTURAL ACTIVITIES

4. Mining operations: 

Mining is a process where in minerals below the earth are extracted using large equipments. During the process dust and chemicals are released in the air causing massive air pollution. This is one of the reason which is responsible for the deteriorating health conditions of workers and nearby residents.

MINING OPERATIONS

5. Indoor air pollution: Household cleaning products, painting supplies

emit toxic chemicals in the air and cause air pollution. Have you ever noticed that once you paint walls of your house, it creates some sort of smell which makes it literally impossible for you to breathe?

Suspended particulate matter popular by its acronym SPM, is another cause of pollution. Referring to the particles afloat in the air, SPM is usually caused by dust, combustion etc. Cooking and heating with solid fuels on open fires or traditional stoves results in high levels of indoor air pollution. Indoor smoke contains a range of health-damaging pollutants, such as small particles and carbon monoxide. According to Global Health Risks: Mortality and burden of disease attributable to selected major risks indoor air pollution is responsible for 2.7% of the global burden of disease.

INDOOR POLLUTION

What are the effects of air

pollutions ?

Acidification: Chemical reaction involving air pollutants can create acidic compounds which can cause harm to vegetation and buildings. Sometimes, when an air pollutant, such as sulfuric acid combines with the water droplets that make up clouds, the water droplets become acidic, forming acid rain. When acid rain falls over an area, it can kill trees and harm animals, fish, and other wildlife.Acid rain destroys the leaves of plants.When acid rain infiltrates into soils, it changes the chemistry of the soil making it unfit for many living things that rely on soil as a habitat or for nutrition. Acid rain also changes the chemistry of the lakes and streams that the rainwater flows into, harming fish and other aquatic life.

ACID RAIN

ACID RAIN

Eutrophication:

Rain can carry and deposit the Nitrogen in some pollutants on rivers and soils. This will adversely affect the nutrients in the soil and water bodies. This can result in algae growth in lakes and water bodies, and make conditions for other living organism harmful. Eutrophication is a condition where high amount of nitrogen present in some pollutants gets developed on sea’s surface and turns itself into algae and adversely affects fish, plants and animal species. The green colored alga that is present on lakes and ponds is due to presence of this chemical only.

5.Effect on Wildlife:  • Just like humans, animals also

face some devastating effects of air pollution. Toxic chemicals present in the air can force wildlife species to move to new place and change their habitat. The toxic pollutants deposit over the surface of the water and can also affect sea animals.

WILD LIFE AFFECTED BY POLLUTION

6. Depletion of Ozone layer:  Ozone exists in earth’s stratosphere

and is responsible for protecting humans from harmful ultraviolet (UV) rays. Earth’s ozone layer is depleting

due to the presence of chlorofluorocarbons, hydro

chlorofluorocarbons in the atmosphere. As ozone layer will go thin, it will emit

harmful rays back on earth and can cause skin and eye related problems.

UV rays also have the capability to affect crops.

CFCs CAUSE OZONE DEPLETION

Respiratory and heart problems:

The effects of Air pollution are alarming. They are known to create several respiratory and heart conditions along with Cancer, among other threats to the body. Several millions are known to have died due to direct or indirect effects of Air pollution. Children in areas exposed to air pollutants are said to commonly suffer from pneumonia and asthma.

AIR POLLUTION AFFECTING HUMAN

GREEN HOUSE EFFECT In the result of air pollution number of

green house gases are increase rapidly. The man-made (or

anthropogenic) component of the greenhouse effect is caused by man’s activities that emit greenhouse gases

to the atmosphere.The most important of these is the burning of fossil fuels. Fossil fuels contain carbon, and when they are burnt this carbon combines with

oxygen in the atmosphere to form carbon dioxide.

GREEN HOUSE EFFECT CAUSE GLOBAL WARMING

WHAT IS GLOBAL WARMINGGlobal warming is an occurrence which results to the rise in the average temperature of the earth's atmosphere. Due to extreme pollution from factories and automobiles in the earth's atmosphere, greenhouse gases like carbon dioxide and nitrous oxide form a thick layer in the upper atmosphere and traps the sun's rays from being reflected back to outer space. This eventually leads to a rise in temperatures as the sun warms the earth. Global warming also called the greenhouse effect occurs as a result of the gradual increase of the air temperature in the earth's lower atmosphere. The gases from the greenhouses escape to the atmosphere to form a blanket' that prevents the suns radiations from going to the stratosphere thus keeping the earth an average of 33 degrees centigrade warmer than it would be if this greenhouse effect did not occur. Some green house gases are like carbon dioxide, methane, Nitrous oxide and Chlorofluorocarbons

Ground-level ozone:Chemical reactions involving air pollutants create a poisonous gas ozone (O3). Gas Ozone can affect people’s health and can damage vegetation types and some animal life too.

EFFECTS OF GROUND LEVEL OZONE

Particulate matter:Air pollutants can be in the form of particulate matter which can be very harmful to our health. The level of effect usually depends on the length of time of exposure, as well the kind and concentration of chemicals and particles exposed to. Short-term effects include irritation to the eyes, nose and throat, and upper respiratory infections such as bronchitis and pneumonia. Others include headaches, nausea, and allergic reactions. Short-term air pollution can aggravate the medical conditions of individuals with asthma and emphysema. Long-term health effects can include chronic respiratory disease, lung cancer, heart disease, and even damage to the brain, nerves, liver, or kidneys. Continual exposure to air pollution affects the lungs of growing children and may aggravate or complicate medical conditions in the elderly.

EFFECT OF PARTICULATE MATTER ON HUMAN HEALTH

14.3.3: describe how incineration of waste material contributes to the problem of air

pollution giving examples from daily

life;

Air Problems Caused By Incineration Of Waste Materials.

Incinerator plants are the source of serious toxic pollutants: dioxins; furans; acid gases; particulates; heavy metals; and they all need to be treated very seriously. There must be absolute prioritization given to human health requirements and protection of the environment. The emissions from incinerator processes are extremely toxic.Some of the emissions are carcinogenic… We must use every reasonable instrument to eliminate them altogether.

Many people would like to believe that waste disappears when it is burnt. In fact the burnt waste is transformed into ashes and gas. (A large incinerator produces the equivalent of 300 wheelie bins of exhaust gases from its chimneys every second). As this happens, chemical reactions lead to the formation of hundreds of new compounds, some of which are extremely toxic. The number of substances released from a waste incinerator may run into thousands. So far, scientists have identified a few hundred substances as hazardous. Numerous studies confirm that a typical incinerator releases a cocktail oftoxic chemicals, including dioxins, lead, cadmium, mercury and fine particles, into the atmosphere

14.3.4: suggest what the government

should do more to control air pollution

resultingfrom auto exhaust;

Controlling Air

Pollution.

Government (or community) level preventionGovernments throughout the world have already taken action against air pollution by introducing green energy. Some governments are investing in wind energy  and solar energy, as well as other  renewable energy, to minimize burning of fossil fuels, which cause heavy air pollution.Governments are also forcing companies to be more responsible with their manufacturing activities, so that even though they still cause pollution, they are a lot controlled. Companies are also building more energy efficient cars, which pollute less than before. Government should provide local transport to people to reduce burning fossil fuels.

Air pollution prevention, monitoring and solution.

Solution efforts on pollution is always a big problem. This is why prevention interventions are always a better way of controlling air pollution. These prevention methods can either come from government (laws) or by individual actions. In many big cities, monitoring equipment have been installed at many points in the city. Authorities read them regularly to check the quality of air.

Recommended