(a) (i) Pollution; is the release of toxic or harmful substances into the environment by their natural forces or man and other animals to an extent that causes biological damage to man and his resources.
(1) Pollutants of air are: Smoke, fumes, dust, harmful gases e.g sulphurdioxide, hydrogen sulphide, ammonia, chlorine/nitrogen oxides, carbon monoxide, pollen grains and soot.
(2) Pollutants of water are: sewage, excreta/faeces, pesticides, chemical wastes/chemicals from factories, fertilizers, slurry/waste from farms, petroleum/ crude oil, heated water, oil spillage.
(b)(i) Effects of water pollution on organisms are:
(1) Destruction or death of valuable aquatic species such as sea birds, fishes e.t.c.
(2) Food chain is affected, or disrupted.
(3) Pollutants encourage bacterial growth leading to reduced amounts of dissolved oxygen/biological oxygen demand in water. This leads to death of fishes and other organisms.
(4) Causes algae blood or putrification while water is rendered unsafe for domestic, drinking, industrial use or recreation.
(5) It also leads to migration of water animals.
(ii) Ways of preventing water pollution:
(1) There should be efficient and proper sewage disposal system.
(2) Dumping of refuse or petro-chemical by-products into rivers/streams/ponds or seas should be avoided.
(3) The use of efficient techniques to deal with or prevent oil spillage should be adopted.
(4) Industries should be sited away from residential areas and water bodies.
(5) Government /local authorities should strictly monitor all industrial wastes and carry out public enlightenment.
(6) Industrial effluents and hot water should be re-cycled.
(c)(i) Sources of noise pollution are:
(1) Factory or industrial noise.
(2) Aeroplane/aviation noise (taking off and landing of aeroplanes).
(3) Railway engine/locomotive noise.
(4) Automobile/ car horns/sirens.
(5) High pitched musical sounds from loud speakers/drumming.
(6) Noise from mills/sawmills/ grinding mills/electronic gadgets and generators.
(7) Artillary shots /shelling/canon shots.
(8) Thunder noise.
(ii) Effects of noise pollution on man:
(1) Loss of hearing /deafening /hard hearing/hearing difficulty.
(2) Emotional disorder/anxiety / fright and lack of concentration.
(3) High blood pressure/hypertension.
(4) General irritation/short temper.
(5) Changes in behaviour.