The Taj Mahal one of the seven wonders of the world is located in Agra . It is made of white marbles . The effect of pollutants on it has become a matter of concern for archeologists and environmentalists . Motor vehicles and the industries located in and around Agra for rubber processing , chemicals , Iron foundries , Mathura oil refinery have been responsible for producing pollutants like SO₂ , NO₂ smoke , dust , soot etc . These gases react with the rain to form acid rain . Acid rains corrode the marble of the Taj Mahal . Suspended Particulate Matter (SPM) , such as the soot particles emitted by mathura oil refinery has turned the marble from white to yellow . Taking this in to account , the Supreme Court of India has suggested several steps to save the Taj . They are :
(i) Switch over to cleaner fuels like CNG and LPG .
(ii) Use unleaded petrol in vicinity of Taj Mahal .
(iii) Shift polluting industries to the outside of Agra city .