(a) Describe causes and effects of water pollution. (10mks) (b) Describe the various control measures for water borne diseases. (10mks)

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a)
  • Agrochemical from neighboring farms causes eutrophication e.g. pesticides; poison the fish and plants life (living organism)
  • siltation – reduce photosynthesis; clog gills of fish; causes turbidity
  • -industrial wastes e.g lead, mercury (heavy metals)hence poisoning; are fixed in the food chain that gets its way to man
  • untreated sewage – causes eutrophication;  reduce oxygen in water; causes decomposition; causes diseases; increases turbidity reducing light penetration
  • spilt oil from tankers or used oil from garage; limits supply of oxygen to aquatic life; covers stomata of plants; clogging gills and feathers of bird
  • hot water – kills organisms; reduces concentration of oxygen
10 MARKS
b)
  • proper sanitation
  • proper hygiene
  • boiling drinking water
  • avoid coming into contact with water bare footed
  • draining stagnant water
  • washing fruits with clean water
  • proper cooking of food
  • destroying the vectors
  • proper storage of food / cover food .
10 MARKS

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