Pollution is the introduction of contaminants into the natural environment that changes the physical, chemical or biological characteristics of air, land, and water, which harmfully affect human life.
The occurrence of unwanted physical, chemical and biotic changes Which generally cause imbalance in our ecology or environment through the air, land or water is called environmental pollution or pollution. The pollution may be either natural or artificial (man made). The substances or factors through which changes occur are called pollutants and generally pollutants have been divided into two groups
The pollutant is anything including a chemical, geochemical substance or a biological product that has undesired effects or adversely affects the usefulness of a resource
In the normal way there are two basic types of pollutants-
(i) Non-degradable pollutants:
Non-degradable pollutants are those which either do not degrade or degrade extremely slowly in the natural environment. Such as aluminum cans, mercury salts, DDT, etc.
The pollutants of this group do not decompose (reduce) into the simpler products and these pollutants are generally toxics and enter into the chain of food of the organisms and poise them. The substances like DDT, pesticide, insecticide, mercury, lead, arsenic, aluminium, plastic, radioactive substances, wastes etc are the examples of non-biodegradable pollutants.
(ii) Biodegradable pollutants:
Biodegradable pollutants Such as the domestic sewage which rapidly decomposed by the natural process or Some artificial System that enhance nature’s great capacity to decompose and recycle.
The pollutants of this group are decomposed by various microorganisms like bacteria, fungi etc. and the decomposed substance enters into a bio-geo-chemical cycle. These decomposed substances become the part of pollution (pollutants), whenever such substances are excessively produced then these are not absorbed. Various substance like residues of domestic kitchen, Faeces (stools) and urine, agricultural residues in the form of by-product paper, wood, cloths etc. are the examples of biodegradable pollutants.
Types of pollution :
On the basis of the pollution spread various types of pollution of our environment can be classified in the following groups-
Different types of pollution are
noise pollution are given below:
The air is basically a mixture of oxygen, nitrogen, CO2 etc and these gases have a definite ratio and the occurrence of imbalance in their ratio produces air pollution.
Source : The source of pollution can be classified into two groups
1. Natural source :
The natural source of air pollution are forest fire, ashes of volcano, dessert sandy storm, decomposition of organic substance, flying pollen grains in air etc.
2. Artificial (man made) source :
Various components like population explosion, deforestation, urbanization, industrialization etc. are the artificial (man made) sources of air pollution. Also through various human activities like man made gases-carbon monoxide (CO), sulphur dioxide (SO2), hydrocarbon, nitrogenous oxides and some others like lead, arsenic, asbestos, dust particles, radioactive substances etc. are major air pollutants which spread air pollution rapidly.
★Release or occurrence of any foreign materials or gases in the atmosphere, which may be harmful to man, animals, and vegetation, etc., is known as air pollution.
★Important sources of air pollution are power and heat generating system, producing the large quantity of waste gases, use of insecticides and fungicides, etc.
★Motor vehicles alone contribute about 60% of air pollution in major cities like Mumbai, Delhi, Kolkata, and Chennai.
★Particulate air pollutant is any materials suspended in the atmosphere. They consist of fine solids or liquid droplets suspended in the air.
★One of the most harmful effects of smoke is the smog formation, which makes fog heavier and darker.
★Photochemical smog Hydrocarbons and nitrogen oxides, when mixed in the atmosphere formed ozone and complex organic gases in the presence of UV radiation in sunlight. This, in turn, causes photochemical smog. It comprising of O3, H2O2, PAN, etc.
★Smog is a mixture of smoke and fog arises from many sources including factories, oil refineries, etc.
★Photochemical smog is responsible for causing eye-watering ‘ and respiratory distress in human beings.
★Cigarette smoke, motor vehicles, industrial plants are the common sources of carbon monoxide (CO).
★Carbon monoxide is the most poisonous gas which causes suffocation because hemoglobin combines with CO.
Hb + CO -> Carboxyhaemoglobin
★Large amount of carbon monoxide, when inhaled leads to symptoms as laziness, exhaustion of body, headache, etc.
★Burning of fossil fuels is the main cause of sulfur dioxide pollution.
★ Sulfur dioxide causes different respiratory distress in animals.
Losses Due to Air Pollution
1. The presence of larger amount of carbon monoxide (CO) in air causes, harassment, irritation, headache, chronic mental sickness, uncomfortable surrounding etc. The haemoglobin of the blood directly reacts with carbon monoxide (CO) and forms a complex carboxyl haemoglobin stable compound, which is deadly poisonous (toxic). In human beings it causes too much suffocation and in few cases sometimes demise (death) occurs.
2. Ultra violet rays are appearing on the earth’s surface in excess amount due to the depletion of ozone layer. The human eyes and their immune system can damage through ultraviolet rays and even skin cancer may be happened through it specially to white people. Indirectly it causes global acid rain, ecological imbalance, non-availability of the global edible oils etc.
3. Acid rain is caused by air pollution and it appears in the presence of nitrogen and sulphur dioxide which are damaging the historical monument, buildings, idols etc. The acid rain makes the soil acidic and the fertility of the soil start to spoil Which adversely affects the agricultural productivities.
4. Through the smoke emission pipe of the motor vehicles free lead releases in the open atmospheric air which causes disease like anthrax, accezema etc. in the human beings.
5. Some pesticides also produce pollution by entering inside the food chain of the organisms and increase their concentration in the organisms. This process is called Bio-magnification and because of it in kidney, brain and in the circulatory system various . types of disorders (defects) appear.
6. Arsenic makes the plants poisonous Which causes the animals death on eating the plants.
7. Fossil fuels (coal, petroleum etc) When burnt then carbon dioxide (CO2) and methane (CH4) gases are produced and they prevent the thermal radiations emitting from the earth’s surface to go outside from the atmosphere. Thus the temperature of the earth increases and consequently the weather abruptly changes and see level also increases. Thus a substantial increase of temperature may cause to melt the glaciers and ice floated peaks and a devastating flood may appear.
8. The emergent SO2 gas from the outlets of factories may produce the severe pain in the respiratory tracks and can damage the lungs of human beings.
acid rain is any form of precipitation with high levels of nitric and sulfuric acids. it can occur in the form of snow fog and even dry materials that settle to earth most. Acid rain is caused by human activities when people burn fossil fuels sulfur dioxide and nitrogen oxides are released into the atmosphere these gases react with water oxygen and other substances to form sulfuric and nitric acid. Winds may spread these acidic solutions over hundreds of miles after it falls to earth.
Acid rain enters water systems as runoff and sinks into the ground this can make water toxic to prey fish, clams fish and other aquatic animals. The rest of the food chain including non aquatic species such as birds is often affected as well as a drain also harms forests by damaging trees leaves robbing. The soil of essential nutrients and making it hard for trees to take up water by designing cleaner power plants and using fewer fossil fuels.We can reduce the number of pollutants that create acid rain.
SO2 (oxidised)→SO3 + H2O→H2SO4
NO (oxidized)→NO2 + H2O→HNO3
★Acid rain damages buildings and statues of limestone.
★Acid rain is also harmful to some aquatic forms.
★If there is an increase in CO2 concentration, then the thick layer of this gas prevents the heat from being re-radiated out. This thick CO2 layer thus functions like the glass panels of a greenhouse allowing the sunlight to filter through but preventing the heat from being re-radiated in outer space. This is so called greenhouse effect.
★ Carbon dioxide is chiefly produced by the burning of fossil fuels like coal, petroleum and natural gas.
★Carbon dioxide contributes the maximum to the greenhouse effect on earth.
★Green-house effect is related to global warming.
★Both methane (CH4) and chlorofluorocarbons (CFCs) are major greenhouse gases.
★Layer of the atmosphere (about 30-50 km above earth surface in the stratosphere) which provides a thermal blanket and radiation shield to the earth by absorbing much of the incoming shortwave radiation, which is very harmful to the living organism, especially in causing skin cancer contains the ozone.
★In 1975, atmospheric scientists first discovered the formation of the ozone hole, maximum over Antarctica.
★Chlorofluorocarbons and chlorofluoromethanes (CFMs) released into the stratosphere, where they dissociate to release free chlorine atom that causes depletion of ozone.
Water pollutants : Various compounds of calcium and magnesium and some other substances are dissolved in the natural sources of water and make the water impure. Some microorganisms like protozoa, bacteria and other microbes also pollute the water. The oil in water, heavy metals, detergents, domestic wastes, radioactive wastes etc. come under the category of the water pollutants.
★The presence of some inorganic, organic, biological, radiological or physical foreign substances or particles, in the water that tends to degrade its quality, is called water pollution.
★Most of our water bodies as ponds, lakes, streams, rivers, sea, oceans have become polluted due to industrial growth, urbanization and other man-made problems.
The chief sources of water pollution are
★ It consists of excreta of animals.
★A major source of water pollution is raw or partially discharged sewage thrown into natural resources of water, e.g., rivers, lakes, streams, etc.
★ The industries that cause pollution are printing, electroplating, soap manufacture, rubber, plastics etc.
★ Caustic soda and chlorine factories release heavy metals, such as mercury, cadmium, chromium, copper, lead, etc.
★Mercury poisoning occurred in Minamata city, Japan in 1953, where more than 100 persons died or suffered serious nerve damage from eating fish taken from Minamata Bay.
★Cadmium poisoning is called Itai-Itai (ouch-ouch) in Japan.
Effect of Heavy Metal Water Pollution
★Adding a large amount of inorganic fertilizers to crop fields results in fertilizer pollution.
★ Nitrite poisoning or methemoglobinemia occurs in infants and farm animals by poisoning of nitrite.
★Eutrophication It means the enrichment of nutrients by human activity.
★Eutrophic it refers to lakes that are highly productive in terms of organic matter formed and well supplied with nutrients.
★Biological Oxygen Demand (BOD) is the amount of oxygen required for biological oxidation by microbes in any unit volume of water.
★The greater the amount of organic matter in water, higher the BOD.
★The excessive use of pesticides causes water pollution by penetrating through the soil and getting dissolved in soil water.
★Spraying of DDT on crops produces pollution of air soil and water.
★Biological amplification (magnification) Increase in the concentration of a persistent chemical by the organisms at successive trophic levels in a food chain.
★Biological monitoring Direct measurement of changes in the biological component of habitat based on the evaluation of the number and/or distribution of organisms or species.
Losses Due to Water Pollution
1. The disease like Typhoid, Cholera, Hepatitis, Jaundice etc. spread due to water pollution.
2. The acid and alkali present in the water can destroy microorganism and in it self purification process of the water of rivers is also disrupted.
3. The mercury, arsenic and lead present in the polluted water exhibit the toxic activities for the organisms (living beings).
4. Exterior flowing excreta (faces) or stools mixes With water promotes the growth of the algae and it spreads on the surface of the water. Whenever algae’s die these start to decompose and there exists the deficiency of oxygen in the water, consequently aquatic creatures begin to die.
5. The pollutants chromium and cadmium are the main components of the marine water pollution and sometimes marine organisms (living beings) die.
The deformed structure of the land or soil which is mainly causes by the solid waste substances is called soil pollution. The solid (waste) substances usually come from homes, animal houses, industries, agriculture and from some other places. The heap of these waste substances comprises ashes, glasses, the residues of fruits and green vegetables, paper, cloths, plastic, rubber, leather, bricks, sands, metals, residues of animal houses etc. Also various chemicals like compounds of sulfur and lead spread in air are appeared on the land and mixed up With soil and the soil is polluted. Also to enhance (increase) the soil fertility, various types of pesticides, insecticides, germicides etc. are utilized and these chemical substances collectively pollute the soil. These chemical substances adversely affect the fertility of the soil slowly and steadily and enter into the food Chain of the almost all organisms.
The heap of solid wastes not only deforms the natural beauty of the ecosystem but also damages our surroundings. Also pigs, dogs, rats, flies, mosquitoes etc frequently and randomly move and spread bad smell through these heap of wastes. Non-biodegradable wastes disrupt the water supply and contaminate the water up to some extent and it becomes the ultimate destination of the reproductive activities of the mosquitoes and flies. The mosquitoes are the vectors of various diseases like Dengue, Malaria, Kalazar etc Which usually reside in the polluted water.
★Soil is the most important component of the Earth.
All the plants grow over Earth’s crust (soil).
★ These plants serve as food for herbivore animals, thus supports the animals living on earth.
★Any foreign substance (organic pollutants) that enters the soil will adversely affect soil productivity.
★Three types of soil pollutants may be found in nature
(a) Pollutants that are washed out of the atmosphere when came in contact with it, may pollute the soil and Create soil pollution.
(b) Pesticides, insecticides, and biocides, sprayed over the crops may find their way along with water to the soil.
(c) Nitrogenous fertilizers, mixed with soil to increase its productivity may sometimes have negative effects on the soil.
★One of the major soil pollution problems in large cities is the disposal of plastics.
★Plastic articles are non-biodegradable.
★An unstable atomic nucleus may undergo spontaneous disintegration or decay. This process produces radiation and the atoms that undergo disintegration are said to be radioactive.
★Radiation is energy, which travels in waves or particles.
★Radiation can be measured in Curies.
★Atmospheric radiation [natural and man-made sources), background radiation (cosmic rays, nucleotides such as Radium 223, Uranium 238, Carbon 14) and man-made radiation (X-rays, nuclear Weapon testing) etc are some of the major sources of ionizing radiations.
★Exposure of man of radiation may cause cancer, genetic damage, and infant mortality.
★The most outstanding danger at present for the survival of living beings on earth is a radiation hazard.
★Chernobyl disaster occurred in Ukraine, USSR 011 26th April 1986. It was an explosion at the nuclear power station releasing huge amount of radioactive substances into the atmosphere.
★Strontium-90, a radioactive pollutant causes bone cancer and degeneration of tissues in human beings.
★ Iodine-131, radioactive isotopes are used in the detection of thyroid cancer.
★Mothers who received abnormal doses of X-rays for diagnostic purposes during their pregnancy tend to produce Mongol children.
★Due to radioactive pollution, radiation stress leads to the reduction in species diversity at the ecosystem level.
Sound or Noise Pollution:
The unwanted loud voices or noises listened all around the surroundings by the human beings form the sound pollution
Source :– The chief source of the sound pollution is loudness or sharp noises, Whatever be the process of generation, it doesn’t matter. There are so many examples like cooler, scooter, TV, car, train, rocket, domestic equipment’s, aircraft, loudspeaker, washing machine etc. are the sources of the sound pollution. But some normal voices or music produced by the musical instruments, like from guitar, harmonium etc. which are sweeter and joyful for the heart, mind and soul are not the part of sound pollution.
★ Noise pollution means the unwanted sound dumped into the atmosphere.
★ The main sources of noise pollution are factories and industries, transportation (air, rail, and road), community and religious activities.
★There are two basic properties of sound
★ It is the strength of sensation of sound perceived by the individual.
★ It is measured in decibels (dB).
Sound Level at Various Sources
★Sounds beyond 80 dB can be safely regarded as pollution as it harms a hearing system.
★The World Health Organisation (WHO) has fixed 45 dB as the safe noise level for a city.
★ Loudness is also expressed in sones.
1 sone = loudness 0f 40 dB sound pressure at 1000 Hz.
★Number of vibrations per second.
★It is denoted as hertz (Hz).
★The noise has the adverse effect on man reducing hearing capacity, flushing the skin and constricting stomach muscles.
★Deafness can be caused due to continuous noise exposure.
★Noise also produces ulcers, headache, heart diseases, high blood pressure, nervousness, etc.
Losses Due to Sound or noise Pollution:
1. A longer duration of loudness or noise may adversely affect the audibility ability and sometimes human beings may become deaf.
2. Sometimes too noisy voices causes the activities like irritation, ill-temperateness, headache, sleeping disorder etc.
3. Also due to the sharp loudness blood pressure and heart beat of the human bodies abruptly increase.
4. Sound pollution sometimes causes accumulation of cholesterol inside the arteries and consequently blood pressure increases. Thus ill-temperdness, anger, frustration, excitement etc. appear.
5. If human beings remain in the sharp loudness for a longer duration then laziness and stupidness come into existence.
6. Also a sharper loudness causes the secretion of the hormone adrenal which become more frequent.
7. The reproductive and metabolic activities are adversely affected if human beings continuously remain in a loud sound for a longer duration.
8. Sound pollution causes feable sence organs and nervous system.