1. CONSEQUENCES OF RAW SEWAGE & NITRATE FERTILIZERS

2. SEWAGE 1.FROM HOUSE A. HUMAN WASTE B. KITCHEN WASTE 1. FOOD RESIDUE 2. DETERGENTS 2. INDUSTRIAL WASTE A. ACIDIC & ALKALINE CHEMICALS B. TOXIC METALS ( Cr, Cu, Zn)

3. 3. WATER POLLUTION A. ANIMAL SLURRIES LEAKAGE FROM FARM WASTE B. RUN OFF WTAER FROM FARM FIELDS ( ARTIFICIAL FERTILIZERS ) Raw sewage & nitrate polluted run off water discharged into a river causes:

4. 1.SUSPENDED SOLIDS effect - reduction in penetration of sun - O2 demand increased during decomposition of organic material 2. PHOSPHATES effect – eutrophication (rapid growth of algae)

5. 3. HEAVY METALS effect – toxic to aquatic organisms & humans if drunk 4. MICROORGANISMS ( viruses, bacteria, fungi, & protozoa ) effect – disease if drunk

6. 5. DETERGENTS effects - foam on surface of water to affect aeration - eutrophication 6. NITROGENOUS COMPOUNDS effects - NH4 are toxic to fish - eutrophication - algal bloom encouraged

7. - algal respiration at night increases BOD (biochemical oxygen demand) results if depletion of dissolved O2 in the water - death in algal bloom results in increase of BOD (while algae is being broken down)

8. - certain blue-green bacteria produce toxins during algal bloom growth - high nitrate concentrations and toxic if water is drunk