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Pollution has happened because of the mixing of dangerous unnatural ingredients into the natural resources which causes imbalance in the ecosystem and thus various health hazards to the human beings and animals. Pollution is damaging the ecosystem and destroying the balance. This is all because of the industrialization, urbanization, deforestation, technological advancement, over population, etc. All these are the big reason of increasing level of toxic gases (causing air pollution), solids/liquids wastes (causing water, food and soil pollution) and sound (causing noise pollution). All are the reason of imbalance in the natural ecosystem in some direct or indirect ways.