Over the past two decades, India’s most famous tourist attraction Taj Mahal located in Agra (U.P), has become a matter of concern. Experts have warned that pollutants in air are discolouring its white marble. So, it is not only living organisms that get affected by polluted air but non-living things like buildings, monuments and status also get affected. The industries located in and around Agra like rubber processing, automobile, chemicals and especially the Mathura oil refinery, have been responsible for producing pollutants like sulphur dioxide and nitrogen dioxide.

These gases react with the water vapour present in the atmosphere to form sulphuric acid and nitric acid. The acid drop down with rain, making the rain acidic. This is called acid rain. Acid rain corrodes the marble of the monument. The phenomenon is also called “Marble Cancer”. Suspended particulate matter, such as the root particles emitted by Mathura oil refinery, has contributed towards the yellowing of the marble. The Supreme court has taken several steps to save the Taj. It has ordered industries to switch to cleaner fuels like CNG (Compressed Natural Gas) and LPG liquified Petroleum Gas). Moreover the automobiles should switch over to unleaded petrol in the the Taj zone.