air pollution seminar

AIR POLLUTION

By : SUDHEESH.K.P

Roll No.:

34

Semester,Branch:

S6,CT EVENING

Institution

KGPTC WESTHILL

Introduction

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.AIR POLLUTION

E-mail:[email protected]

Introduction

Air pollution is the introduction of particulates, biological molecules, and many harmful substances into Earth's atmosphere, causing diseases, allergies, death to humans, damage to other living organisms such as animals and food crops, or the natural or built environment. Air pollution may come from anthropogenic or natural sources.The atmosphere is a complex natural gaseous system that is essential to support life on planet Earth.


PollutantsAn air pollutant is a substance in the air that can have adverse

effects on humans and the ecosystem. The substance can be solid particles, liquid droplets, or gases. A pollutant can be of natural origin or man-made. Pollutants are classified as primary or secondary. Primary pollutants are usually produced from a process, such as ash from a volcanic eruption. Other examples include carbon monoxide gas from motor vehicle exhaust, or the sulfur dioxide released from factories. Secondary pollutants are not emitted directly. Rather, they form in the air when primary pollutants react or interact. Ground level ozone is a prominent example of a secondary pollutant. Some pollutants may be both primary and secondary: they are both emitted directly and formed from other primary pollutants.


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


There are two types of pollutants

•Primary pollutants•Secondary pollutants


Primary PollutantsE-mail:[email protected]

Major primary pollutants produced by human activity include:


• Sulfur oxides (SOx) - particularly sulfur dioxide, a chemical compound with the formula SO2. SO2 is produced by volcanoes and in various industrial processes. Coal and petroleum often contain sulfur compounds, and their combustion generates sulfur dioxide. Further oxidation of SO2, usually in the presence of a catalyst such as NO2, forms H2SO4, and thus acid rain. This is one of the causes for concern over the environmental impact of the use of these fuels as power sources.

{Sulfur Dioxide Pollution

Sulfur dioxide(SO2)E-mail:[email protected]

• Nitrogen oxides (NOx) - Nitrogen oxides, particularly nitrogen dioxide, are expelled from high temperature combustion, and are also produced during thunderstorms by electric discharge. They can be seen as a brown haze dome above or a plume downwind of cities. Nitrogen dioxide is a chemical compound with the formula NO2. It is one of several nitrogen oxides. One of the most prominent air pollutants, this reddish-brown toxic gas has a characteristic sharp, biting odor.

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 2014 - global air quality levels(released 14 December 2015)

Nitrogen dioxide(NO2)E-mail:[email protected]

• Carbon monoxide (CO) - CO is a colorless, odorless, toxic yet non-irritating gas. It is a product of incomplete combustion of fuel such as natural gas, coal or wood. Vehicular exhaust is a major source of carbon monoxide.

Carbon dioxide in Earth's atmosphere if half of global-warming emissions are not absorbed.(NASA simulation; 9 November 2015)

{

Carbon monoxide(CO)E-mail:[email protected]

• Volatile organic compounds (VOC) - VOCs are a well-known outdoor air pollutant. They are categorized as either methane (CH4) or non-methane (NMVOCs). Methane is an extremely efficient greenhouse gas which contributes to enhanced global warming. Other hydrocarbon VOCs are also significant greenhouse gases because of their role in creating ozone and prolonging the life of methane in the atmosphere. This effect varies depending on local air quality. The aromatic 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.


• Particulates, alternatively referred to as particulate matter (PM), atmospheric particulate matter, or fine particles, are tiny particles of solid or liquid suspended in a gas. In contrast, aerosol refers to combined particles and 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. Averaged worldwide, anthropogenic aerosols—those made by human activities—currently account for approximately 10 percent of our atmosphere. Increased levels of fine particles in the air are linked to health hazards such as heart disease, altered lung function and lung cancer.

Particulate matterE-mail:[email protected]

• Persistent free radicals connected to airborne fine particles are linked to cardiopulmonary disease.

• Toxic metals, such as lead and mercury, especially their compounds.


• Chlorofluorocarbons (CFCs) - harmful to the ozone layer; emitted from products are currently banned from use. These are gases which are released from air conditioners, refrigerators, aerosol sprays, etc. On release into the air, CFCs rise to the stratosphere. Here they come in contact with other gases and damage the ozone layer. This allows harmful ultraviolet rays to reach the earth's surface. This can lead to skin cancer, eye disease and can even cause damage to plants.

Chlorofluorocarbons (CFCs)E-mail:[email protected]

• Ammonia (NH3) - emitted from agricultural processes. Ammonia is a compound with the formula NH3. 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. Ammonia, either directly or indirectly, 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


• Odours — such as from garbage, sewage, and industrial processes Radioactive pollutants - produced by nuclear explosions, nuclear events, war explosives, and natural processes such as the radioactive decay of radon.


Secondary pollutants include:


• Particulates created from gaseous primary pollutants and compounds in photochemical smog. Smog is a kind of air pollution. Classic smog results from large amounts of coal burning in an area caused by a mixture of smoke and sulfur dioxide. Modern smog does not usually come from coal but from vehicular and industrial emissions that are acted on in the atmosphere by ultraviolet light from the sun to form secondary pollutants that also combine with the primary emissions to form photochemical smog.

Beijing air on a 2005-day after rain (left) and a smoggy day (right)

Santiago Chile smog winter

SmogE-mail:[email protected]

• Ground level ozone (O3) formed from NOx and VOCs. Ozone (O3) is a key constituent of the troposphere. It is also an important constituent of certain regions of the stratosphere commonly known as the Ozone layer. Photochemical and chemical reactions involving it drive many of the chemical processes that occur in the atmosphere by day and by night. At abnormally high concentrations brought about by human activities (largely the combustion of fossil fuel), it is a pollutant, and a constituent of smog.

Ozone (O3)E-mail:[email protected]

• Peroxyacetyl nitrate (PAN) - similarly formed from NOx and VOCs.E-mail:[email protected]

Minor air pollutants include:

• A large number of minor hazardous air pollutants. Some of these are regulated in USA under the Clean Air Act and in Europe under the Air Framework Directive

Nitrogen dioxide diffusion tube for air quality monitoring. Positioned in London City.

• A variety of persistent organic pollutants, which can attach to particulates

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State parties to the Stockholm Convention on Persistent Organic Pollutants


https://en.wikipedia.org/wiki/Nitrogen_dioxide

https://en.wikipedia.org/wiki/London

SourcesThere are various locations, activities or factors which are responsible for

releasing pollutants into the atmosphere. These sources can be classified into two major categories.Anthropogenic (man-made) sources: These are mostly related to the burning of multiple types of fuel.

• Stationary sources include smoke stacks of power plants, manufacturing facilities (factories) and waste incinerators, as well as furnaces and other types of fuel-burning heating devices. In developing and poor countries, traditional biomass burning is the major source of air pollutants; traditional biomass includes wood, crop waste and dung.


• Controlled burn practices in agriculture and forest management. Controlled or prescribed burning is a technique sometimes used in forest management, farming, prairie restoration or greenhouse gas abatement. Fire is a natural part of both forest and grassland ecology and controlled fire can be a tool for foresters. Controlled burning stimulates the germination of some desirable forest trees, thus renewing the forest.

Air pollution in New Delhi

Delhi has been compared to a gas chamber since November 2016.

While some attribute this to the careless use of firecrackers during Diwali, other factors could be burning of solid waste in and around Delhi, vehicular emissions, dust by the roadside and around construction sites in Delhi and stubble burning in Punjab and Haryana.

2016 Air pollution level hit record high in New Delhi in the past week following Diwali celebration.

Air quality monitoring, New Delhi, India.

Diwali is a festival of lights and not pollution


• Mobile sources include motor vehicles, marine vessels, and aircraft.

• Fumes from paint, hair spray, varnish, aerosol sprays and other solvents


• Military resources, such as nuclear weapons, toxic gases, germ warfare and rocketry


• Waste deposition in landfills, which generate methane. Methane is highly flammable and may form explosive mixtures with air. Methane is also an asphyxiant and may displace oxygen in an enclosed space. Asphyxia or suffocation may result if the oxygen concentration is reduced to below 19.5% by displacement.


Natural sources:

• Dust from natural sources, usually large areas of land with little or no vegetation

• Methane, emitted by the digestion of food by animals, for example cattle

Dust storm approaching Stratford, Texas.{E-mail:[email protected]

• Radon gas from radioactive decay within the Earth's crust. Radon is a colorless, odorless, naturally occurring, radioactive noble gas that is formed from the decay of radium. It is considered to be a health hazard. Radon gas from natural sources can accumulate in buildings, especially in confined areas such as the basement and it is the second most frequent cause of lung cancer, after cigarette smoking.


• Smoke and carbon monoxide from wildfires

• Vegetation, in some regions, emits environmentally significant amounts of Volatile organic compounds (VOCs) on warmer days. These VOCs react with primary anthropogenic pollutants—specifically, NOx, SO2, and anthropogenic organic carbon compounds — to produce a seasonal haze of secondary pollutants. Black gum, poplar, oak and willow are some examples of vegetation that can produce abundant VOCs. The VOC production from these species result in ozone levels up to eight times higher than the low-impact tree species.


• Volcanic activity, which produces sulfur, chlorine, and ash particulates


https://en.wikipedia.org/wiki/Sulfur

Effects

Acid Rain• 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).

• It can have harmful effects on plants, aquatic animals and infrastructure.

• Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids.

• Some governments have made efforts since the 1970s to reduce the release of sulfur dioxide and nitrogen oxide into the atmosphere with positive results. Nitrogen oxides can also be produced naturally by lightning strikes, and sulfur dioxide is produced by volcanic eruptions.

• Acid rain has been shown to have adverse impacts on forests, freshwaters and soils, killing insect and aquatic life-forms, causing paint to peel, corrosion of steel structures such as bridges, and weathering of stone buildings and statues as well as having impacts on human health.

Acid RainE-mail:[email protected]

Acid RainNatural phenomena• emissions from volcanoes.• biological processes that occur on the

land, in wetlands, and in the oceans.• electrical activity in the atmosphere

such as lightning.• Acidic deposits have been detected in

glacial ice thousands of years old in remote parts of the globe


Acid RainHuman activity• The principal cause of acid rain is sulfur and nitrogen

compounds from human sources, such as electricity generation, factories, and motor vehicles.

• Electrical power generation using coal is among the greatest contributors to gaseous pollutions that are responsible for acidic rain.

• The gases can be carried hundreds of kilometers in the atmosphere before they are converted to acids and deposited.

• In the past, factories had short funnels to let out smoke but this caused many problems locally; thus, factories now have taller smoke funnels. However, dispersal from these taller stacks causes pollutants to be carried farther, causing widespread ecological damage.


Acid Rain

Acid clouds can grow on SO2 emissions from refineries, as seen here in Curaçao. Since 1998, Harvard

University wraps some of the bronze and marble statues on its campus, such as this "Chinese stele", with waterproof covers every winter, in order to protect them from erosion caused by acid rain and acid snow

Acid rain can have severe effects on vegetation. A forest in Europe.

{Effect of acid rain on statues


Acid RainHuman health effects• Acid rain does not directly affect human health.• The acid in the rainwater is too dilute to have direct adverse

effects. However, the particulates responsible for acid rain (sulfur dioxide and nitrogen oxides) do have an adverse effect.

• Increased amounts of fine particulate matter in the air do contribute to heart and lung problems including asthma and bronchitis.


Ozone Depletion• 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.

{Image of the largest Antarctic ozone hole ever recorded (September 2006), over the Southern pole

Ozone DepletionE-mail:[email protected]

Ozone Depletion

Layers of the atmosphere (not to scale). The Earth's ozone layer is mainly found in the lower portion of the stratosphere from approximately 20 to 30 km (12 to 19 mi).

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Ozone Depletion

Biological effects

• Ozone depletion would magnify all of the effects of UV on human health, both positive (including production of Vitamin D) and negative (including sunburn, skin cancer, and cataracts). In addition, increased surface UV leads to increased tropospheric ozone, which is a health risk to humans.

NASA projections of stratospheric ozone concentrations if chlorofluorocarbons had not been banned

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Global Warming• Global 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

Global WarmingE-mail:[email protected]

Global Warming

2015 – Warmest Global Year on Record (since 1880) – Colours indicate temperature anomalies (NASA/NOAA; 20 January 2016).


Global Warming

Map of the Earth with a six-metre sea level rise represented in red.{


Warning………

Deaths from air pollution in 2004


Solution!• Understand the concept of Reduce, Reuse and

Recycle: Air Problems Caused By Incineration Of Waste Materials.Do not throw away items that are of no use to you. In-fact reuse them for some other purpose. For e.g. you can use old jars to store cereals or pulses. Many people would like to believe that waste disappears when it is burnt. In fact the burnt waste is transformed into ashes and gas.

• Use public mode of transportation: Encourage people to use more and more public modes of transportation to reduce pollution. Also, try to make use of car pooling. If you and your colleagues come from the same locality and have same timings you can explore this option to save energy and money.

• Conserve energy: Switch off fans and lights when you are going out. Large amount of fossil fuels are burnt to produce electricity. You can save the environment from degradation by reducing the amount of fossil fuels to be burned. Use energy efficient devices. CFL lights consume less electricity as against their counterparts. They live longer, consume less electricity, lower electricity bills and also help you to reduce pollution by consuming less energy.


Solution!• Emphasis on clean energy resources: Clean energy

technologies like solar, wind and geothermal are on high these days. Governments of various countries have been providing grants to consumers who are interested in installing solar panels for their home. This will go a long way to curb air pollution.


Solution!E-mail:[email protected]

ThanksE-mail:[email protected]

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