Ans: The corrosion of the Taj Mahal due to acid rain is called ‘marble cancer’. Industrilization in the surroundings of Taj Mahal has been the major threat. Because of these indutries many pollutant gases are releasing into the atmosphere. Gases, like methane, nitrous oxide and water vapour, also contribute to the greenhouse effect, and, along with carbon dioxide, are collectively called the greenhouse gases.
Taj Mahal is regarded as the 'jewel' of India. But, it is under threat due to the industries in and around Taj. The industries located in and around Agra, like rubber processing, 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 . When these acids react with water in the rain, they form acid rain. This acid rain s very corrosive in nature. The yellowing of the Taj Mahal is due to the deposition of soot particles that are emitted from the Mathura oil refinery.