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Pollution of air and water. — Science STD 8 — Question

Maharashtra BoardEnglish MediumSTD 8SciencePollution of air and water.5 Marks
Question
State the harmful effects of water pollution.
✓

Answer

Pollution is not a distant phenomenon anymore. It is affecting the quality of our day to day lives.
Following are harmful effects of water pollution:
  • The chemicals such as arsenic, lead and flourides discharged by the industries are very toxic to plants and animals.
  • The hot water released by certain industries raises the temperature of the water body. It adversely affects the plants and animals living in it.
  • The fertilizers act as nutrients for the algae to grow. When these algae die, they act as a nutrient for decomposers like bacteria. As a result of this process, a lot of oxygen in the water gets used up and leads to the deficiency of Oxygen in the water. This may kill the aquatic organisms.
  • Water contaminated with sewage may contain bacteria, viruses, fungi and parasites which can cause diseases like cholera, typhoid and jaundice.

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