Red Fort facing damage from air pollution
New Delhi: Severe air pollution in the national capital has begun to visibly damage one of India’s most iconic heritage monuments — the Red Fort. A new study has found that toxic air has led to the formation of “black crusts” on the 17th Century Mughal-era structure, threatening its intricate carvings and sandstone walls.
Study reveals alarming findings
The research, published in the peer-reviewed journal Heritage in June, was conducted between 2021 and 2023 by experts from India and Italy. Their findings show that pollution-related deposits, measuring between 0.05mm and 0.5mm thick, have accumulated on the fort’s surfaces due to chemical interactions between airborne pollutants and the stone.
Researchers also noted evidence of blistering, flaking, and deterioration on arches, vaults, windows and delicate carvings. These changes, if left unaddressed, could irreversibly harm the UNESCO-listed monument that draws millions of visitors each year.
Red Fort’s historic significance
Built by Mughal emperor Shah Jahan in the 17th Century, the Red Fort is a key symbol of India’s history. It became the site of India’s first flag hoisting by Prime Minister Jawaharlal Nehru on 16 August 1947, a tradition that continues on Independence Day.
The fort, with its massive red sandstone walls, is among Delhi’s most visited monuments. However, its cultural and historic value is now at risk due to Delhi’s worsening air quality.
Pollution threat to heritage monuments
Delhi frequently ranks among the world’s most polluted cities, with winter smog making headlines almost every year. Conservationists have long warned about the damage caused by particulate matter (PM2.5 and PM10) to heritage monuments.
The Supreme Court had in 2018 flagged similar concerns when the Taj Mahal’s white marble was found to be turning yellow and even greenish-brown due to air and water pollution. The court had urged the Uttar Pradesh government to take immediate conservation steps.
Recommendations for protection
The Red Fort study recommends early interventions such as applying protective stone sealants in highly affected areas. It also stresses the need for systematic monitoring and cleaning to prevent the progressive accumulation of black crusts.
“The formation of a black crust begins as a thin deposit that can be removed in early stages. However, once the deposits grow thicker, they can permanently damage the stone,” the study warns.
Conclusion
The findings highlight a growing challenge for conservation authorities — how to preserve India’s historical treasures in the face of rapid urbanisation and persistent pollution. Without urgent action, Delhi’s toxic air could leave permanent scars on the Red Fort, undermining not only its beauty but also its historical legacy.