India's Pollution: Understanding The Complex Causes

India is one of the most polluted countries in the world, with 1.4 billion people exposed to unhealthy levels of air pollution. In 2019, 21 of the 30 most polluted cities in the world were in India, and the air pollution caused by industrial and vehicular emissions, construction, and waste burning is responsible for more than 2 million deaths a year. This is due to a combination of unique geographical factors and rising emissions, with the problem being particularly acute in the north of the country, where the Himalayas trap pollutants.

Industrial and vehicular emissions

India is one of the most polluted countries in the world. In 2019, 21 of the 30 most polluted cities in the world were in India. A 2016 study found that at least 140 million people in India breathe air that is 10 times or more above the WHO safe limit. India is the fourth-largest emitter of greenhouse gases (GHG), contributing 7.08% of global emissions. It also ranks third among countries with the worst air quality.

Vehicular emissions are a major contributor to India's poor air quality. India is the fifth-largest car manufacturer in the world, and in 2019, it had one of the highest compound annual growth rates (10%) of vehicle registration. The transport sector accounts for a quarter of India's total emissions, with road transport accounting for three-quarters of transport emissions (and 15% of total global CO2 emissions). Vehicular emissions contribute 20-30% of Particulate Matter (PM) 2.5 at the breathing level of air quality. PM2.5 refers to particles with a diameter of less than 2.5 micrometres that remain suspended in the air for longer. Vehicles in India contribute about 290 gigagrams (Gg) of PM2.5 annually. The transport sector also accounts for 8% of India's total Greenhouse Gas (GHG) emissions, and in Delhi, it exceeds 30%. Carbon monoxide (CO) is a highly toxic, colourless, and odourless gas that arises from the incomplete combustion of fossil fuels. Vehicular emissions are the primary source of CO in highly polluted cities like New Delhi. Nitrous oxide (NOx), which arises from the high-temperature combustion of fossil fuels, is also commonly found in Indian cities like New Delhi, Bangalore, Mumbai, and Kolkata, and is linked to vehicular pollution. NOx contributes to the formation of ground-level ozone, which is highly correlated with respiratory diseases and asthma.

The use of private cars and trucks is steadily increasing in India, and there is a continued reliance on gasoline and diesel. Two-wheelers dominate India's vehicle fleet, but their emissions are starting to decline due to fast electrification. India's Prime Minister has set the goal of reaching net-zero carbon emissions by 2070. To achieve this, ambitious policies are needed to reduce energy demand and transition to electric vehicles (EVs). EV sales are projected to reach nearly 35% of total vehicle sales in 2030, and policies must aim for a 50% share to meet the 2070 goal. The transition to EVs can significantly reduce citizens' exposure to air pollution. However, the current and future batches of internal combustion engine (ICE) vehicles will likely remain a substantial part of the on-road fleet until 2040 and beyond. This requires tightening emissions standards and modifying technical parameters for vehicle testing to reduce emissions.

India has implemented various initiatives to address air pollution, including the National Clean Air Program, which aims to reduce particulate matter pollution by 30% by 2024. The country is also developing Real Driving Emissions (RDE) procedures to overcome the limitations of laboratory tests that may not reflect real-world driving conditions. The Indian Drive Cycle (IDC) and the Modified Indian Drive Cycle (MIDC) are driving cycles used for vehicle testing and certification, but they may not cover all the complex driving conditions in India. The Bharat stage (BS) emission standards regulate the output of air pollutants from internal combustion engines and spark-ignition engine equipment, including motor vehicles. Additionally, policies such as the fitness test for older passenger and commercial vehicles aim to reduce emissions from older, less efficient vehicles.

Construction dust and debris

India is one of the most polluted countries in the world. In 2022, six of the world's top ten most polluted cities were located in India, and in 2019, 21 of the 30 most polluted cities were in India. The air pollution in India is so severe that it is visible, and it is estimated to cause the premature deaths of 2 million Indians every year.

One of the main contributors to India's particulate air pollution is construction dust and debris. The country is largely under construction, with projections suggesting that around 70% of the buildings in India's cities by 2030 are yet to be built. This means that controlling the dust produced by roads and worksites is an important, yet often neglected, part of clearing the air.

The process of mixing concrete, for example, is estimated to contribute 10% of the coarse pollutants in Delhi's air. A study of 19 large Delhi construction sites found that the air quality around all of them exceeded safe limits by at least three times. Construction and demolition operations contribute to windblown dust, which can remain in the air for days or even weeks. The dust from these sites, as well as the production of raw materials such as bricks and concrete, is a significant source of harmful pollutants in the city's atmosphere.

The Indian government has set forth guidelines to minimize the impact of construction sites on the environment, but there is a lack of adherence and enforcement. Construction companies are required to submit reports on their compliance with the Ministry of Environment and Forests guidelines, but builders often cut corners, and cities like Delhi lack the capacity to safely process the amount of construction waste produced.

The issue of construction dust and debris is not unique to Delhi, as other parts of India are also experiencing the impacts of infrastructure development. The question of how to address this source of pollution is complex, as banning construction work can further stir up dust and debris, and halting infrastructure development in a growing country like India seems counter-productive and unsustainable.

Dependence on thermal power for electricity

India's dependence on thermal power for electricity is a significant contributor to its pollution problem. Thermal power plants emit a large amount of carbon and other harmful emissions, such as boiler slag, flue gas desulphurization materials (FGD), fly ash, and bottom ash. In fact, over 86.35% of the total installed capacity of Indian thermal power stations is produced from coal, and the country's coal-fired power plants emit 50-120% more CO2 per kWh than their EU counterparts.

The coal used in Indian power plants is of low calorific value and high ash content, resulting in a higher consumption rate than power plants in other countries. For example, Indian power plants consume about 0.7 kg of coal per kWh of power generation, while US thermal power plants consume about 0.45 kg of coal per kWh. This high ash content is a major cause of environmental pollution, and the formation of coal combustion by-products (CCBs) has a considerable impact on the environment and human health.

The states that produce the most thermal electricity, such as Jharkhand, Chhattisgarh, and Odisha, bear a disproportionate pollution burden compared to the consuming states. This is because India's electricity and environmental regulatory structures do not compensate these states for the pollution generated by their central sector thermal power plants. As a result, the net exporting states of central sector power producers bear the full burden of pollution, while the net importing states enjoy clean electricity.

The Indian government has recognized the need to reduce emissions and has committed to achieving 50% of its cumulative electric power installed capacity from non-fossil fuel-based energy resources by 2030. The government also plans to retire coal-based plants that are at least 25 years old and contributing to excessive pollution. However, as of 2020, there was no retirement plan for the captive power sector, which accounts for a significant portion of India's thermal power generation.

In conclusion, India's reliance on thermal power for electricity, especially coal-fired power plants, is a major contributor to its pollution problem. The high ash content of Indian coal, the inefficient nature of the power plants, and the lack of compensation for polluting states all contribute to the environmental and health impacts of thermal power generation in India.

Waste burning

India is the third-largest waste-generating country in the world, and open waste burning is a widely established practice of waste disposal in developing nations. Municipal solid waste burning contributes significantly to air pollution, releasing harmful particulate matter (PM2.5 and PM10), carbon monoxide, and other non-methane, volatile organic compounds (NMVOC). The fumes and particulate matter released from these fires pose severe health risks, including respiratory problems, cardiovascular complications, and cognitive impairment.

Open waste burning is a critical aspect of plastic pollution, and toxic fumes from burning plastic waste are harmful to both human and environmental health. In addition, paddy-residue burning is associated with poor air quality in northwest India during October and November each year. The burning of garden waste is also a common occurrence across many cities.

India has made progress in tackling indoor air pollution, phasing out kerosene lamps, and encouraging the use of cleaner fuels such as Liquefied Petroleum Gas (LPG) for cooking. However, residential fuel usage, including the burning of cow dung, is still a major source of air pollution.

Without strong policies to promote recycling and upcycling of non-biodegradable waste, and the conversion of biodegradable waste to biogas, open waste burning is likely to become India's largest source of air pollution by 2035. To prevent this, measures are needed to reduce unsegregated organic waste and promote the processing of waste into biogas. Decentralized waste management systems can also help reduce the burden on centralized locations and lower the likelihood of dumping and burning.

Use of wood and dung for cooking and heating

India has a serious problem with air pollution, and one of the main contributors is the use of wood and dung for cooking and heating. Over two-thirds of India's 1.3 billion people continue to rely on carbon-emitting biomass and dung-based fuel for cooking. This has led to a million deaths a year from indoor pollution. The World Health Organization's Household Air Pollution and Health report states that over 50% of premature deaths among children under five are due to pneumonia caused by particulate matter (soot) inhaled from household air pollution.

The use of wood and dung for cooking and heating has serious adverse consequences for health, the environment, and a nation's economic development. The smoke from burning wood and dung contains harmful pollutants, including particulate matter (soot), hydrocarbons, carbon monoxide, and oxides of nitrogen. These pollutants can cause respiratory and cardiovascular diseases such as asthma, bronchitis, COPD, lung cancer, and heart attacks. The smoke from burning wood and dung also contributes to the haze and smoke observed above rural and urban India.

The problem is especially acute in rural areas, where women invest valuable time and effort in collecting fuel instead of focusing on their children's education or income generation possibilities. Entrenched beliefs and the easy availability of cow dung for free also make it harder to solve the problem. Most villagers think that since cow dung is easily available and free, they should not have to spend money on cleaner alternatives like LPG (cooking gas) connections or gas stoves.

According to ecologist Meena Kapahi, indoor air pollution is responsible for a high degree of morbidity and mortality and warrants immediate intervention by the general public and policymakers. Kapahi's report, "Indoor Air Pollution: Sources, Health Effects, and Mitigation Strategies," highlights the need for education and grassroots-level change to eradicate the problem.

To address the issue of indoor air pollution from burning wood and dung, India faces the challenge of providing access to adequate and affordable energy. Initiatives by local government bodies and NGOs can help reduce dependence on natural resources. For example, the International Fund for Agricultural Development's initiative in the state of Odisha sets a good example.

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