Tackling Air Pollution: Do Telas Breathe Easy?

Delhi, the capital territory of India, has been dubbed the world's most polluted city. In 2022, a US-based survey of 7,000 cities worldwide found that Delhi's air pollution was the worst of any major city. The air pollution in Delhi is a public health emergency, with 2.2 million children suffering from irreversible lung damage and a high incidence of chronic respiratory diseases and asthma. The city's air quality index (AQI) has reached hazardous levels, with a reading of 493 in 2024—more than 30 times the World Health Organization's (WHO) limit. The primary sources of pollution in Delhi include vehicle emissions, road dust, industrial sources, and domestic fuel burning. Despite efforts to reduce pollution, such as shutting down schools and construction sites, the situation persists, and experts urge leaders to address transport and heavy industry as the root causes.

Delhi's air quality is the worst of any major city in the world

Delhi, India's capital, has consistently been ranked as the world's most polluted capital city. In 2023, Delhi's annual average PM 2.5 level was 92.7 µg/m3, earning it the top spot on the World Air Quality Report's list of 114 capital cities. The following year, Delhi maintained high pollution levels, with an annual average of 91.6 µg/m³, according to the same report.

The air quality in Delhi is a serious issue, with the city's residents dealing with a months-long spell of intense smog during the winter. This smog is caused by a combination of factors, including industrial and vehicular emissions, crop burning in neighbouring states, low wind speeds, and firecrackers during festivals. The situation has severe health implications, with air pollution causing neurological, cardiovascular, and respiratory diseases, lung capacity loss, and even cancer. The University of Chicago's Air Quality Life Index notes that the high levels of air pollution in northern India are reducing the life expectancy of over 510 million people by an average of 7.6 years.

The Indian government has attempted to address the air pollution issue, with local and national authorities implementing temporary measures during the winter months, such as sprinkling water and restricting vehicle entry into cities. However, these measures are often seen as band-aids that fail to address the root causes of the problem. Experts attribute the worsening air quality in India to rapid industrialisation and weak enforcement of environmental laws, with factories failing to follow pollution-control measures. Rapid construction has also been identified as a contributing factor to the rising levels of pollution.

Delhi's air quality is a pressing environmental challenge that poses significant health risks to its vast population. With vehicle emissions being a major contributor, there is a growing need to transition to sustainable transport and invest in clean energy generation. Addressing the root causes of air pollution and implementing long-term solutions are crucial to improving the air quality in Delhi and protecting the health and well-being of its residents.

Vehicle emissions, road dust, and industrial sources are major contributors to air pollution

Vehicle emissions are a major contributor to air pollution. Cars, trucks, and buses powered by fossil fuels emit more than half of the nitrogen oxides in the air and are a significant source of heat-trapping emissions. These emissions have been linked to adverse impacts on nearly every organ system in the body, and the exposure to pollution is inequitable, disproportionately affecting Latinos, Blacks, and lower-income households. Heavy-duty vehicles, such as trucks and buses, make up only about 10% of all vehicles on the road, yet they generate over 25% of global warming emissions, nearly 45% of NOx emissions, and almost 60% of direct PM2.5 emissions from on-road vehicles.

Particulate matter (PM), one of the major pollutants from motor vehicles, includes soot from vehicle exhaust. Fine particles, less than one-tenth the diameter of a human hair, can penetrate deep into the lungs and pose a serious threat to human health. Diesel exhaust is a significant contributor to PM pollution, and volatile organic compounds (VOCs) from vehicle emissions react with nitrogen oxides in the presence of sunlight to form ground-level ozone, a primary component of smog. While ground-level ozone can irritate the respiratory system, causing coughing, choking, and reduced lung capacity, PM2.5 pollution can increase the risk of premature death.

Road dust, including dust from unpaved roads and construction sites, is another significant source of air pollution, contributing about 38% of PM2.5 in cities. The increase in population leads to a rise in the number of vehicles, waste, and energy consumption, all factors that contribute to pollution. Industrial activities, agricultural practices like stubble burning, and poor waste management also play a role in air pollution, particularly in densely populated areas.

To combat vehicle emissions and improve air quality, the Environmental Protection Agency (EPA) has implemented stringent emissions standards for passenger vehicles and heavy-duty diesel vehicles, such as tractor-trailers and large buses. The EPA also provides funding through programs like the Diesel Emissions Act Reduction Program to support projects that aim to reduce harmful emissions from diesel engines and improve public health.

The Badarpur coal-fired power plant was a significant source of pollution, but it has since been shut down

The Badarpur Thermal Power Station, a coal-fired power plant in South Delhi, India, was a significant source of pollution in the city. The plant contributed only about 8% of Delhi's electric power but was responsible for 30-40% of the city's particulate matter pollution from the energy sector, according to a 2015 study by the Centre for Science and Environment. The plant's inefficiency was also noted, with the poor quality and high cost of coal contributing to its deteriorating performance.

The power plant's pollution was so severe that it was temporarily shut down during the Great Smog of Delhi to alleviate acute air pollution. The plant's proximity to the Yamuna River further exacerbated concerns, as the highly polluted water from the river adversely affected the plant's operations and contributed to the city's water pollution.

Recognizing the urgency of the situation, the government decided to retire the Badarpur plant, along with another NTPC coal-powered plant, the Rajghat power station. The Badarpur Thermal Power Station, which had an installed capacity of 705 MW, was permanently shut down on October 15, 2018. This decision was made due to the completion of the Tughlakabad substation, which could now take the load off the BTPS.

The closure of the Badarpur plant was not without its challenges and controversies. There were concerns about the potential loss of employment for thousands of workers in the power sector. Additionally, charged electric panels at the plant posed a fire hazard, and officials involved in the closing process expressed uncertainty about the technical aspects of safely shutting down the plant. Nevertheless, the retirement of the Badarpur coal-fired power plant marked a significant step towards reducing air pollution in Delhi and improving the health and well-being of its residents.

Stubble burning by farmers is a widely blamed cause of Delhi's smog

Delhi, the capital territory of India, has been found to be the most polluted major city in the world. The air pollution in Delhi has been described as a "toxic smog" that has reached hazardous levels. The poor air quality in Delhi has been linked to the premature deaths of about 2 million people every year and is the fifth-largest killer in India.

Stubble burning by farmers has been widely blamed for causing Delhi's smog. The burning of crop residue by farmers in Delhi's neighbouring states, such as Punjab, Haryana, Madhya Pradesh, and Uttar Pradesh, has been identified as a significant contributor to the city's air pollution. While the percentage contribution of stubble burning to Delhi's pollution has been debated, with some data placing it at around 1-2%, other sources have reported it as high as 38%. This discrepancy may be due to variations in the scale used to convert pollutant concentrations into Air Quality Index (AQI) scores. The impact of stubble burning on Delhi's air quality is particularly notable during the harvest seasons in the neighbouring states, with the number of farm fires in these states significantly impacting the air quality in Delhi.

The Indian government has implemented various measures to mitigate the impact of stubble burning on Delhi's air quality. These measures include distributing crop residue management machines, establishing a farm residue biomass supply chain, and implementing a graded response action plan (GARP) to address peak pollution levels. GARP includes strategies such as limiting vehicular movement and closing educational institutions. Additionally, the government has also focused on raising awareness among farmers about the impact of stubble burning and promoting alternative methods for managing crop residue.

While stubble burning is a significant contributor to Delhi's smog, it is important to recognize that other factors also play a role in the city's poor air quality. Vehicular emissions, industrial activities, residential practices, road dust, construction, and garbage burning are all significant sources of pollution in Delhi. The complex interplay of these factors underscores the need for coordinated action by state and central governments to implement effective strategies to improve air quality and protect public health in the capital.

Emergency measures to reduce pollution include closing schools, stopping construction, and banning certain vehicles

Banning certain vehicles is one emergency measure that has been implemented in various cities to reduce air pollution. For example, Beijing banned cars one day a week during the 2008 Olympics, and Paris banned cars with even-numbered license plates on one day and cars with odd-numbered license plates on another. However, the effectiveness of these measures has been questioned. In Mexico City, a regular ban on cars did not lead to a significant reduction in pollution as people found creative ways to get around the restrictions, such as using less fuel-efficient vehicles.

Another strategy to reduce pollution is to implement measures that discourage driving and encourage the use of public transportation or active transportation, such as biking. For example, Paris made public transportation and bike-sharing free during a car ban. While this may not be financially or politically sustainable in the long term, it can be an effective short-term solution during emergency pollution events.

In addition to banning certain vehicles, closing schools can also be an emergency measure to reduce pollution. Schools can implement strategies to reduce traffic-related pollution exposure, especially for schools located near heavily traveled roads or other sources of vehicular pollution. Working together with the community, schools can develop plans to mitigate the health risks associated with extreme weather events and infectious diseases.

Finally, stopping construction activities can also help reduce air pollution. Construction is a significant contributor to air pollution, and organizations in the sector have a shared responsibility to limit their emissions. Strategies to reduce pollution from construction include improving waste management and disposal, using modern equipment that produces less noise and pollutants, and implementing noise barriers and personal protective equipment (PPE) to reduce the impact of noise pollution on workers and local residents.

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