India's Air Pollution: Causes And Concerns

India has become the most polluted country on Earth, with 1.24 million deaths attributed to air pollution in 2017. The problem is most acute in the north of the country, where the Himalayas form a barrier, preventing poor air from dissipating. The main causes of India's air pollution include vehicular emissions, industrial emissions, thermal power plants, construction dust, waste burning, and the burning of wood and cow dung for cooking and heating by poor households.

Industrial and vehicular emissions

India's rapid economic growth has come at a cost to human health and the environment. Industrial and vehicular emissions are key contributors to India's air pollution crisis.

Industrial Emissions

Industrial emissions are a major source of air pollution in India. In 2011, India was the third-largest producer of greenhouse gases after China and the United States. Industrial pollution accounts for 51% of India's air pollution.

The Indian government has implemented policies to address this issue, such as the Air (Prevention and Control of Pollution) Act in 1981, which, unfortunately, has failed due to poor enforcement. In 2019, India launched the National Clean Air Programme, aiming for a 20-30% reduction in PM2.5 and PM10 concentrations by 2024.

The International Institute for Energy Conservation is also working with government, industrial, and utility partners to build air quality monitoring and tracking capacity and implement cost-effective air pollution reduction strategies in the states of Gujarat and Odisha.

Vehicular Emissions

Vehicular emissions are a significant contributor to India's air pollution, particularly in urban areas. The transport sector accounts for a quarter of India's total emissions, with road transport responsible for three-quarters of that figure. In Delhi, transport emissions exceed 30% of the city's total emissions.

Vehicles contribute about 290 gigagrams (Gg) of PM2.5 annually and around 8% of India's total greenhouse gas emissions. The use of adulterated fuel blends in taxis and auto-rickshaws, which is common in South Asia, increases emissions of harmful pollutants.

To combat this issue, the Indian government has mandated the manufacture, sale, and registration of only BS-VI (BS6) vehicles from April 2020. A gradual rollout of ethanol-blended fuel is also proposed, with E10 fuel supply by April 2022 and phased rollout of E20 from April 2023 to April 2025.

Construction dust and debris

The dust and debris from construction sites can spread onto nearby roadways and into the surrounding ecosystem, affecting air quality and wildlife populations. A range of construction activities contribute to this, including the use of diesel generators, vehicles, and heavy equipment, which produce diesel engine exhausts. In addition, noxious vapours from oils, glues, thinners, paints, treated woods, plastics, cleaners, and other hazardous chemicals are commonly used on construction sites, further adding to air pollution.

The Indian government has implemented measures to address this issue. The Ministry of Environment and Forest has made it mandatory for construction projects over a certain size to obtain environmental clearances and implement dust preventive measures. Construction site owners are also required to follow the C&D Waste Management Rules, 2016, which outline proper waste collection, transportation, storage, and processing into recycled or reusable products. However, there has been a lack of adherence to these guidelines, and enforcement remains a challenge.

Initiatives like the Green Building Movement by the Indian Green Building Council (IGBC) offer rating systems that incentivize construction projects to adopt more environmentally friendly practices. These include energy savings, water efficiency, CO2 emissions reduction, improved indoor air quality, and resource stewardship. Additionally, construction companies are being asked to submit reports on their compliance with guidelines on preventing dust and garbage accumulation on their sites.

To protect workers' health, it is important to provide respiratory protective equipment, such as N95 respirators or powered air-purifying respirators (PAPRs), when working in areas with high levels of airborne pollutants. Other protective gear, such as safety goggles and coveralls, is also crucial to minimize skin and eye contact with hazardous substances. Implementing wet methods, such as wet cutting and sweeping, can help minimize dust generation during construction activities. Proper waste management and green construction practices can also play a significant role in reducing air pollution and creating healthier work environments.

Thermal power plants

India's air pollution is a complex issue with many contributing factors. One significant contributor is thermal power plants, which produce a range of harmful emissions.

India's electricity generation sector is the fifth largest in the world, with thermal power plants accounting for 66% of the country's electricity generation. Coal is the primary fuel of choice, contributing to the high levels of emissions from these plants. In 2010-2011, 111 coal-fired power plants with a capacity of 121 GW consumed 503 million tons of coal, leading to the generation of an estimated 580 kilotons of PM2.5, 2100 kilotons of SO2, 2000 kilotons of NOx, and high amounts of other pollutants.

The impact of these emissions on human health and the environment is significant. Air pollution has been linked to reduced life expectancy and various health issues such as chronic obstructive pulmonary disease, heart attacks, strokes, asthma, and cognitive impairment. It also affects agriculture, with increased ozone pollution damaging crops and reducing yields.

To address the pollution from thermal power plants, India has implemented emission standards and regulations. The 2015 emission standards, for example, aimed for a 48% decrease in NOx and SOx, a 40% reduction in PM, and a 60% reduction in mercury emissions. However, there have been challenges in enforcing these standards, and public debates around air pollution often focus on episodic events rather than the year-round baseload pollution from power plants.

It is important to recognize that addressing air pollution in India requires a comprehensive approach that considers various sources, including power plants, industrial emissions, vehicle exhaust, construction dust, waste burning, and the use of solid fuels for cooking and heating in households. By implementing effective regulations, adopting cleaner technologies, and transitioning to renewable energy sources, India can mitigate the pollution from thermal power plants and improve air quality for its citizens.

Fuel adulteration

The use of adulterated fuel has severe consequences for air quality and public health. It increases tailpipe emissions of harmful pollutants, including hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), and particulate matter (PM). Kerosene, in particular, results in higher emissions of HC, CO, and PM, even in catalyst-equipped cars, due to its higher sulfur content and more challenging combustion properties. These emissions contribute to the formation of the Asian brown cloud, which has delayed the onset of the monsoon in India.

Additionally, the unregulated air toxin emissions, benzene, and polyaromatic hydrocarbons (PAHs) are well-known carcinogens, posing long-term health risks to the population. Beyond air pollution, fuel adulteration also reduces engine life and increases maintenance costs for vehicles, further impacting the economic and environmental sustainability of transportation in India.

To address the issue of fuel adulteration, policy interventions are necessary to remove the financial incentives for blending. This could involve restructuring tax rates on different types of fuels to narrow the price gap between gasoline and alternatives. Additionally, stricter enforcement of fuel quality standards and regulations can help deter the use of adulterated fuel blends.

Furthermore, investing in clean energy alternatives and improving access to reliable electricity and clean-burning fuel technologies, particularly in rural areas, can provide viable substitutes for traditional biomass burning practices, reducing the overall demand for adulterated fuels. These comprehensive approaches are essential to mitigating the environmental and health impacts of fuel adulteration in India.

Biomass burning

The burning of agricultural waste, such as crop residue and wheat residue, is also a major source of biomass burning emissions. In India, around 24% of total primary crop residue is openly burned in farms, releasing particulate matter, trace gases, VOCs, and greenhouse gases into the atmosphere. This is particularly prevalent during the summer and post-monsoon seasons, where studies have shown that post-monsoon fires contribute significantly to regional air pollution and population exposure in and around cities like Delhi.

The problem is exacerbated by the lack of pollution control devices in traditional cookstoves and open-field burning, resulting in the unconstrained release of pollutants into the air. The emissions from biomass burning are not limited to rural areas but also affect semi-urban and urban regions, contributing to the compromised air quality in many Indian cities.

While efforts to shift to cleaner cooking fuels, such as LPG, have resulted in a decline in emissions from residential cooking, biomass burning remains the largest contributor to India's air pollution. The unique geography of Northern India, with the Himalayas forming a barrier, further prevents the dispersal of pollution, trapping it in a "big, massive bowl".

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