IndiaA black, sooty crust is causing significant decay to the sandstone walls of Humayun's Tomb, a UNESCO World Heritage site in Delhi. Researchers from IITs at Roorkee and Kanpur identified the cause as prolonged exposure to polluted air, which leads to the formation of a gypsum-based crust on the sandstone. This crust accelerates the monument's deterioration by trapping pollutants like soot, dust, and metal particles from vehicle emissions, construction, and industrial activity. The study highlights that the damage is most severe in sheltered areas of the monument where pollutants accumulate, while more exposed areas experience less buildup due to natural washing by rain. Similar findings were previously observed at Delhi's Red Fort, indicating that this issue is not unique to Humayun's Tomb but part of a broader pattern of environmental degradation affecting historical structures in the city.
Bias read (Center): The article focuses on environmental degradation of a heritage site due to air pollution, with no explicit political framing or bias toward any ideological stance. The emphasis is on scientific research and technical explanations rather than political actors or policies.
