We have seen that the main sources of air pollution are (1) motor vehicles, (2) industries- particularly their chimney wastes, and (3) fossil fuel based plants, as thermal power plants. Steps are to be taken to control pollution at source as well as the release of pollutants in the atmosphere. Biodegradable pollutants alone are not responsible for water pollution, though these indicate level of pollution (through BOD values). Besides these, a substantial pollution load is contributed by non degradable or slow degrading pollutants, such as heavy metals, mineral oils, biocides, plastic materials etc. that are dumped into water. For biodegradable pollutants, pollution may be controlled at source by their treatment for reuse and recycling.
Now we are experiencing the phenomena called Global Warming or simply the exceeding of to much heat due to the increase of carbon emission of the vehicles and factories. As we expected, it can lead to different event like occurence of too much typhoon. Human is powerful in this world they can do whatever they want but we don't know that in all the things we do there is a consequences just Confucius says in his Golden Rule " Do unto others as you would have them do unto you." And now human activities can affect not only the people but our blue planet because they keep on destructing our evironment as a result, the generation that will inherit our planet will see no more.