In a shocking revelation, a study has disclosed that India's national capital Delhi, is breathing poison and dangerous air, stressing that among three
Indian cities, it has the highest concentration of mercury, which can directly affect the kidneys, heart, and cause neurological diseases. The Pune-based Indian Institute of Tropical Meteorology (IITM) conducted a six-year-long study and found that mercury levels in Delhi's air are quite higher than the natural background. However, the study pointed out that the mercury level saw a significant decline in Delhi during the period studied, as compared with previous years. But it also revealed that Delhi's mercury levels are among the highest in South Asia. Also Read: How Many Years of Life You Could Lose by Living in Delhi’s Toxic Air
What are Delhi's current and previous mercury levels?
Mercury is a toxic metal, and also among the top 10 chemicals of major public health concerns, according to the World Health Organisation (WHO). However, its levels vary according to the location, but its global background level is approximately 1.7 ng/m³ in the Northern Hemisphere and 1.3 ng/m³ in the Southern Hemisphere.
The study by the Pune-based institute analysed data from 2018 to 2024 on gaseous elemental mercury, which is a key atmospheric pollutant.
According to the researchers, on average, Delhi's air contained 6.9±4.2 ng/m³ as compared to 2.1±0.7 ng/m³ in Ahmedabad and 1.5 ±0.4 ng/m³ in Pune. If consumed, it can cause severe health-related problems.
This shows that each cubic metre of air in Delhi, which is nearly the amount a human breathes in an hour, has around seven billionths of a gram of mercury on average. Meanwhile, in Ahmedabad, it's around two billionths and 1.5 billionths in Pune.
Whom to blame?
Now, if we look at the reason behind this, it is shocking to know that humans themselves are causing this. The study stressed that coal, traffic and industries are the major reasons behind the increase in mercury level.
The research team revealed that 72 per cent to 92 per cent of mercury in these cities are because of human activities.
"Seasonal and nighttime spikes were especially prominent in Delhi and Ahmedabad during winter, linked to coal use, stubble burning, and stable atmospheric conditions," an IITM scientist said.
If exposure to Mercury continues for 5-10 years (even in small quantities), it can be really dangerous, the chair professor at the National Institute of Advanced Studies told TOI.
Moreover, it mainly harms the nervous system, digestive system, immune system, kidneys and lungs, Gufran Beig, the chair professor, said.
