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For example, factories consume a lot of water and electricity and release harmful chemicals in air, land, and water,
                   thus contaminating the atmosphere. Water pollution caused by factories and other industries can be the most
                   serious problem. They also pollute the air through fossil fuel emissions. These emissions include carbon dioxide,
                   methane, and nitrous oxide, which are harmful to living beings.
                 Pollutants are of two types:

                             Pollutants that can decompose                     Pollutants that cannot decompose

                 Pollutants that break  down  into simpler, harmless  Pollutants which  cannot  be broken down  into  simpler
                 substances naturally  (by the action  of  moisture and  and  harmless substances are called  non-biodegradable
                 bacteria) are called biodegradable pollutants.      pollutants. The harmful effect caused by these pollutants
                                                                     will be there for hundreds of years.

                 Examples: vegetable waste, sewage waste, paper, wood,  Examples: plastics, insecticides, pesticides, chemicals like
                 cattle dung, agricultural waste from organic farms, etc.  mercury or lead, aluminium, glass, etc.
                 Some of the other factors responsible for polluting the environment are as follows:

                 •  Exhaust fumes released from vehicles pollutes the air.
                 •  Excessive use of chemicals in agriculture (like insecticides and fertilisers) affect the alkalinity of the soil or the soil
                   pH. It adversely affects the health of microorganisms and other organisms in the soil.

                 •  Plastic waste like bottles, bags, etc., thrown on land and sea pollutes the water and destroys the flora and fauna.
                 •  Dangerous gases (chlorofluorocarbons or CFCs, methane, carbon dioxide, etc.) released into the air.
                 The various types of pollution are summarised in Table.

                 Types of Pollution
                 Factors                 Land Pollution             Water Pollution             Air Pollution
                 What it is?             •  Damage to the land      •  Adding harmful substances  •  Addition of harmful
                                            because of harmful        and disease causing          gases and particles
                                            substances is known as    bacteria and other           in air results in air
                                            land pollution.           microorganisms to rivers,    pollution.
                                                                      lakes, and oceans results in
                                                                      water pollution.

                 What happens because  •  Diseases, such as         •  Diseases, such as        •  Heart and breathing
                 of this pollution?         dysentery, cholera and    dysentery, diarrhoea,        problems and cancers
                                            typhoid                   jaundice, typhoid, etc.   •  Climate change
                                         •  Less land is available for   •  Local earnings, like
                                            use of forests, farms or   tourism, fishing etc. are
                                            homes                     adversely affected
                                                                    •  Less drinking water

                 Why does it happen?     •  Cutting down forests    •  Throwing waste in water  •  Burning of fuels
                                         •  Harmful pesticides and   •  Leakage from sewer lines  •  Smoke from traffic
                                            fertilisers             •  Release of waste water   •  Burning waste and
                                         •  Mining and heavy          from houses, farms and       remains of crops
                                            construction              factories                 •  Pesticides and
                                         •  Release of sewage,      •  Accidental oil leakage from   fertilisers
                                            toilet waste, waste from   ships                    •  Smoke from factories
                                            houses/factories, and                               •  Dust from construction
                                            chemical waste


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