The Silent Killer - World’s Most Polluted City

 In 2014, The World Health Organization studied the air quality of 1,600 cities in 91 countries. New Delhi, India, was ranked number 1 as the most polluted city in the world. Beyond the findings for Delhi, 13 of the top 20 cities with the highest annual averages of PM2.5 in the WHO study were also in India. The figures were alarming and concerning! 

Using satellite-based remote sensing technology and ground-level data from the Central Pollution Control Board, Dr. Michael Greenstone and his team from WHO produced an insightful study (Greenstone et al., 2015) showing that 660 million people (more than half of India’s population at that time) lived in areas that highly exceed India’s standards for fine particulate pollution. Large portions of India, particularly in the north along the Indo-Gangetic plain, were heavily polluted and in non-compliance with India’s National Air Quality Standards (NAAQS.)

Since 2014, this data has been updated yearly by the W.H.O. Though New Delhi subsequently got displaced from the top of the list, this transition wasn’t due to any action taken to clean its air but because W.H.O. started tracking other more polluted cities worldwide. In November 2016, Delhi’s air was actually the worst it had been in the past 17 years, forcing the Indian government to declare an “emergency situation” and temporarily close schools, construction sites, and power stations until the pollution came under control. These emergency measures were followed only partially, making the situation worse and the pollution levels static at harmful levels. In later years till 2020 (before Covid-19), very stringent measures had to be adopted by the government to curb large-scale construction and waste dumping, checking vehicle emissions, etc. This was also called for because severe bronchial infections and life-threatening diseases were emerging among small children, and many neonatal and maternal deaths and low birth weights were attributed to extreme pollution levels.   

All such efforts were negated due to the Covid-19 that halted many measures and forced the already in effect rules to be abandoned. As a result 2022, in the World Air Quality Report prepared by IQAir, New Delhi ranked fourth on a list of 50 of the world’s most polluted cities regarding PM2.5 levels. IQAir is a Swiss air quality technology company that prepares annual world air quality reports based on data from monitoring stations operated by governments and other institutions worldwide. The data showed that New Delhi had an average PM2.5 level of 92.6 ug/m3, whereas the WHO guideline for annual PM2.5 levels is 5ug/m3. Even after this report, from 2018 to 2022, New Delhi continued to top the IQAir list of the most polluted capital cities. In 2022, New Delhi’s average PM2.5 level was the highest in November. The 2022 report is based on PM2.5 data from 7323 cities and 131 countries. 

Now what causes the toxic and dangerous levels of air pollution in New Delhi? Air pollution in Delhi’s National Capital Region (N.C.R.) comprises a complex mix of pollution from human activities (vehicle emissions, industry, construction, and residential fuel burning) and natural sources like dust. The burning of post-harvest stubble is also a significant contributing factor to this pollution. The heavy concentration of particulate matter is greatly affected by meteorological conditions – in the winter, cold air causes “inversions” that stagnate the air and trap pollution close to the ground. Air flow patterns from Afghanistan and Pakistan collect emissions as they move over the densely urbanized regions of Punjab and Haryana, where farmers burn the straw in their fields and pull this pollution into New Delhi. Pre-monsoon dust storms also contribute to air pollution in the region. City activities also majorly contribute to air pollution. The Delhi-NCR generates more than 11,300 tons per day of municipal solid waste, much of which is eventually burned, adding particulate pollution to the air. Rapid urbanization results in massive infrastructure projects, which add to the dust and particulate pollution. In addition, Delhi has more than 13.4 million vehicles on its roads, with an additional 1,700 added each day, resulting in a breakdown “hotspot.”. Coupled with unregulated construction, industrial non-treated waste disposal, and poorly managed dumping sites that emit toxic fumes, the situation has reached the brink of destruction. Something urgent, immediate, and drastic is needed to reverse the damage.   

In conclusion, we can discern that air pollution in New Delhi has truly gone beyond the national and international prescribed safe limits and is a ticking time bomb unless tackled with strict laws and strict enforcement of nonpolluting measures. A study has also been done to ascertain and confirm that the components of pollution that harm health are usually worst in the winter. Coupled with winter stubble burning and Diwali fireworks, a substantial increase in pollution during the cold weather poses unique risks and challenges. Ground-level ozone, however, peaks in June. Pollution levels often peak around midnight, too, since the air is stiller than daytime. Efforts to mitigate air pollution in New Delhi that began around 2015 have shown varying short-term success. However, an effective long-term strategy has yet to be identified or adopted. In 2022 and 2023, a new wave of policies is in the process of being discussed. The government realizes the impediment to the previous measures and looks to institute new regulations. Finally, no effort shall succeed if human greed and human need surpass the need for environmental sustainability. Hence a public partnership, industrial cooperation, and legislative application are all crucial components of fighting air pollution in and around New Delhi.