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

Maharashtra BoardEnglish MediumSTD 8SciencePollution of air and water.5 Marks
Question
How do industries cause water pollution?
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Answer

Industries cause water pollution in the following ways:
  • Industries such as oil refineries, paper factories, textile and sugar mills and chemical factories discharge harmful chemicals into rivers and streams. These chemicals include arsenic, lead and flourides which are very toxic to plants and animals.
  • The soil is also affected by impure water which causes changes in acidity of soil and affects the growth of worms and plants etc.
  • Some industries and power plants releases hot water into the rivers. Hot water can also be considered as a pollutant. It raises the temperature of the water body and adversely affects the plants and animals living in it.

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