AIR POLLUTION Presented by MOHD ZAKIR ALI VISAKHAPATNAM

AIR POLLUTION Presented by MOHD. ZAKIR ALI VISAKHAPATNAM

ENVIRONMENT § sum of all social, economical , biological, § § physical or chemical factors which constitute the surroundings of man who is both creator and moulder is called environment. Environment consists of Abiotic Biotic and Energy components

SEGMENTS OF ENVIRONMENT n Atmosphere the protective thick gaseous layers surrounding the earth n Hydrosphere It deals with water which includes sea, rivers, oceans, lakes etc. n Lithosphere The solid components of the earth which includes soil, rocks, and other nonliving things. n Biosphere It deals with living things present in atmosphere and hydrosphere.

Types of Pollution 1. 2. 3. 4. Air Pollution Water pollution Soil pollution Sound pollution

COMPOSITION OF ATMOSPHERE • The natural air consists of N 2 = 78. 84% O 2 = 20. 94% CO 2 = 0. 03% Ar. & others= 1%

Air pollution n Direct or indirect introduction of any material in to the atmosphere in an amount that effects the quantity and composition of the outside atmosphere resulting in detrimental effect on human beings and non-living things is called air pollution

Air pollution is most important from public point of view, because every individual person breathes approximately 22000 times a day inhaling about 15 to 22 kgs of air daily. The polluted air causes ill effects.

CAUSES OF AIR POLLUTION NATURAL CAUSES n Volcanic eruptions n Burning of forests n Storms n Virus & bacteria n Earthquakes n n n MAN-MADE CAUSES Increase in human population Rapid industrialization Deforestation Transportation services Agricultural activities Radioactive substances

INDUSTRIAL POLLUTION

VOLCANIC ERUPTION

LAVA

POLLUTANT n The excess concentration any unwanted gaseous substance present in atmosphere that causes harmful effect to the living and nonliving things is called pollutant.

Classification of pollutants 1. primary pollutants The substances which are produced at the source it self and enters into the atmosphere directly. co 2, co, NOx, sox 2. Secondary pollutants. The primary pollutants undergo chemical reaction in presence of sun light and produce a new toxic substances are called secondary pollutants PAN, PBN and any photochemical smog.

Types of pollutants Gaseous pollutants CO, CO 2, NOx, SOx, CFC’s, HF, Hydrocarbons and all other vapours. l Particulates dust, smoke, l Aerosols mist, fog , fumes & gases and smog l

Effects of air pollution n Carbon monoxide: It combines with haemoglobin and forms carboxyhaemoglobin which leads to death. n It causes headache, nausea, hard breathing, cardiovascular disorders and lung cancer.

SULPHUR OXIDES • It causes respiratory problems like bronchitis • It causes chlorosis, necrosis, plasmolysis, and retards growth of plants. • It causes acid rains • It causes corrosion of metals

Carbon dioxide: It leads to rise in global warming. due to which the icebergs melt , water levels increases in oceans and submerge cities Islands may disappear

Nitrogen oxides l l These oxides form PAN and PBN by undergoing chemical reaction in the presence of sun light. They lead to acid rains which damage crops and structures and causes skin cancer, eye irritation and asthma.

Effects of air pollution on plants • Acid rain destroys crops and forests. • SO 2: it causes bleaching of leaves. • NO 2 : it causes bleaching of leaves and reduced fruit production. • HF: it damages the crops.

Effects of air pollution on property u SO 2: it causes corrosion and damages marble structures, eg. , Tajmahal. u NO 2 & H 2 S: cause corrosion of buildings and darkening of painted surfaces.

General effects air pollution l Green house effect l Ozone depletion l Acid rain

DEPLETION OF OZONE LAYER u u The ozone layer is present in stratosphere which is extended from 11 to 15 km from the surface of earth It protects the living things from UV radiation OZONE LAYER is depleted by various pollutants NOX, CFC’s present in the atmosphere. Due to depletion of ozone layer the UV radiation passes on to the surface of the earth and it effects 1. Gobal temperature 2. Rate of photosynthesis 3. Causes skin diseases

Ozone is mainly broken down by chemicals called Chlorofluorocarbons and also by nitrogen oxides. CFC's ironically were first used in large quantities because they were thought to be safe and inert (unreactive) chemicals. They are a group of chemically similar gases used in refrigeration systems, air conditioners, aerosols, solvents and in the production of some types of packaging. Nitrogen oxides are a by-product of fuel burning, e. g. aircraft exhausts. CFC's don't occur naturally, they are man-made chemicals. They are very useful when they are where they are supposed to be, and doing what they are supposed to be doing. But once released into the atmosphere they are a serious pollutants. The actual reactions that destroy ozone are very complicated. They take place on the surface of the ice particles of the Polar Stratospheric Clouds and it takes only a small amount of CFC to destroy an awful lot of ozone.

ionosphere mesosphere stratosphere troposphere Depletion of ozone layer EARTH

Control of air pollution Air pollution can be controlled by § Periodical checking of industrial machinery § Periodical checking of automobile engines. § Industrial zoning i. e. , separation of industries from cities & towns by forests. § Reduction of smoke at source itself, such as installing electrostatic precipitators, etc. , § By growing more trees