How do industries pollute the environment?

Industries cause economic growth of a nation but also result in degradation of environment. Industries are responsible for following type of pollutions:

1. Air pollution — Industries release undesirable gases like sulphur dioxide, carbon monoxide, carbon dioxide etc. as well as dust particles, sprays and mist. Smoke is emitted by chemical factories, paper factories, brick kilns, refineries and smelting plants.
2. Water Pollution — It is caused by organic and inorganic industries wastes and affluents discharged into rivers. The main culprits in this regard are paper, pulp, chemical, textile and dyeing etc.
3. Thermal Pollution — When the hot water from factories and thermal plants is drained into rivers and ponds before cooling it raises the temperature of the water body resulting in thermal pollution. It adversely affects the aquatic ecosystem.
4. Noise Pollution — Noise of factories cause problems like blood pressure, hearing impairment, anger and other psychological issues. Industrial and construction activities, generators, drilling machines make a lot of noise.