Air Pollution's History In India: A Troubled Past

Air pollution in India has been a serious environmental issue for decades, with 21 of the world's 30 most polluted cities in 2019 located in India. The problem has many sources, including industrial and vehicular emissions, construction dust, waste burning, and the use of wood and dung for cooking and heating. In rural areas, biomass burning for cooking and warmth is a major contributor, with indoor air pollution causing 300,000 to 400,000 deaths annually. Large-scale crop residue burning in agriculture is another significant source of pollution, while tyre pyrolysis plants also contribute to the problem. India's air pollution issues have evolved since the 1990s, with a growing number of vehicles and industrial sources, despite tightening emission norms.

The use of fuelwood, agricultural waste, and biomass cakes

India is the world's largest consumer of fuelwood, agricultural waste, and biomass for energy purposes. India's national average annual per capita consumption of fuel wood, agricultural waste, and biomass cakes was 206 kilograms of coal equivalent. The overall contribution of fuelwood, including sawdust and wood waste, was about 46% of the total, with the remaining 54% being agricultural waste and biomass dung cakes. Traditional fuel (fuelwood, crop residue, and dung cake) dominates domestic energy use in rural India, accounting for about 90% of the total. In urban areas, traditional fuel constitutes about 24% of the total. India burns ten times more fuelwood annually than the United States, and the Indian stoves in use are less efficient, producing more smoke and air pollutants per kilogram equivalent.

Fuelwood and biomass cakes are used for cooking and general heating needs. These are burnt in cookstoves known as chulhas, which are present in over 100 million Indian households and are used two to three times daily. Some reports, including one by the World Health Organization, claim that 300,000 to 400,000 people die of indoor air pollution and carbon monoxide poisoning in India due to biomass burning and the use of chulhas. The carbon-containing gases released from biomass fuels are many times more reactive than cleaner fuels such as liquefied petroleum gas.

Biomass burning is a significant contributor to India's air pollution, particularly in rural areas. According to a study, residential biomass burning accounts for up to 90% of the annual anthropogenic PM2.5 emissions in the Indo-Gangetic Plain (IGP), which is home to over half of India's population. The residential energy emissions come primarily from the 78% of people who burn biomass (usually agricultural residues, fuel wood, and dung cakes) for cooking and heating, as it is the most affordable energy source for low-income households.

To address the issue of biomass burning, the Indian government has implemented initiatives such as the Pradhan Mantri Ujjwala Yojana (PMUY), which provides LPG connections and cylinders to households. While PMUY has been successful in creating LPG connections, many households find it challenging to fund the refill of their LPG cylinders despite the incentives. As a result, there are low refill rates, indicating a potential return to biomass burning.

In addition to government initiatives, small interventions such as burning crop residue one hour earlier in the day can provide broad public health benefits by reducing the number of premature deaths caused by particulate matter exposure.

Industrial and vehicular emissions

India is currently the world's fourth-largest emitter of greenhouse gases, contributing 7.08% of global emissions. It is the third most polluted country in the world, with 13 of its North Indian cities among the 15 most polluted cities globally. The country's air pollution is caused by industrial and vehicular emissions, construction, dependence on thermal power, waste burning, and the use of wood and dung for cooking and heating.

Vehicular emissions are a major cause of air pollution in India's urban areas, contributing 27% of the country's overall air pollution. They are the primary source of carbon monoxide (CO), which is a highly toxic, colourless, and odourless gas that arises from the incomplete combustion of fossil fuels. Vehicular emissions also contribute to high levels of nitrous oxide (NOx) in Indian cities, which is linked to respiratory diseases and asthma. The annual sales of cars in India are projected to triple by 2030, increasing exposure to vehicular exhaust emissions.

To mitigate vehicular emissions, the Indian government introduced the Bharat Stage Emission Standards (BSES) in 2000, based on European standards. These standards aim to reduce tailpipe emissions and improve engine design and fuel efficiency. The implementation of BS-VI norms is expected to significantly reduce NOx, HC + NOx, and PM levels. However, the current and future batches of internal combustion engines (ICE) will likely remain a significant contributor to on-road fleets until 2040 and beyond, requiring tighter emission standards and modifications to vehicle testing parameters.

Industrial emissions account for 51% of India's air pollution. The use of fuelwood, agricultural waste, and biomass cakes for cooking and heating is prevalent in over 100 million households, releasing carbon-containing gases and contributing to the Asian brown cloud. India burns ten times more fuelwood than the United States, and the inefficient stoves used produce more smoke and air pollutants. Additionally, unsanctioned tyre pyrolysis plants contribute to severe air pollution and health problems.

To address industrial emissions, India has taken steps towards electrification and the adoption of cleaner technologies. The government has proposed a gradual rollout of ethanol-blended fuel, aiming for an E10 fuel supply by April 2022 and the introduction of E20 fuel by April 2025. The country has also launched initiatives such as the National Clean Air Programme (NCAP), aiming to reduce particulate pollution by 20-30% by 2024, and the creation of green ecological corridors to combat pollution.

Construction dust and debris

Air pollution in India has been a serious environmental issue for decades. In 2019, India was the world's second most polluted country, with 21 out of the 30 most polluted cities in the world. A study based on 2016 data found that at least 140 million people in India breathe air that is ten times or more over the WHO safe limit.

Construction dust can contain harmful substances such as metals, silica, asbestos, and other toxic substances. Regular exposure to construction dust can lead to various health issues for construction workers, including asthma, COPD, silicosis, and even lung cancer. Site managers play a crucial role in reducing exposure to construction dust and debris. Some methods to minimise dust include spraying down outdoor sites with water, using water trucks to wet haul roads, and applying polymers to topsoil before spraying with water.

In addition to controlling dust at the source, it is essential to protect workers from hazardous substances. Personal protective equipment (PPE), such as dust masks and respirators, is essential in preventing the inhalation of dust and other particulates. Employers must ensure workers receive medical exams to ensure proper fitting and usage of respirators before exposure to dust. Other technological advancements, such as smart clothing that detects CO2 levels and monitors vital signs, can also enhance worker safety.

While India grapples with the challenges of construction dust and debris, there are efforts to improve waste management and recycling. For example, the Gujarat Metro Rail Corporation is buying recycled waste to construct the Ahmedabad Metro, and some companies are using drones and remote-controlled vehicles to reduce human exposure to hazardous areas. However, issues such as the disappearance of waste en route to recycling plants and the lack of standardisation in waste product markets across states persist.

Crop residue burning

India is the world's second most polluted country. Fine particulate air pollution (PM2.5) shortens an average Indian's life expectancy by 5.3 years. Of the 30 most polluted cities in the world, 21 were in India in 2019. Air pollution contributes to the premature deaths of 2 million Indians every year. The main contributors to India's particulate air pollution include industrial and vehicular emissions, construction dust and debris, dependence on thermal power for electricity, waste burning, and the use of wood and dung by low-income and rural households for cooking and heating.

The Indian government has attempted to address this issue through various measures and campaigns, including burning bans, fines, and promoting sustainable management methods such as converting crop residue into energy. However, these regulations have had limited efficacy due to socioeconomic factors and the tight schedule of the harvest-to-sowing transition.

Effective solutions to crop residue burning require the implementation of sustainable management practices with government interventions and policies. Composting, biochar production, and mechanization are a few effective techniques to reduce crop residue burning while retaining the nutrients in the soil. Additionally, active stakeholder involvement, including the education and empowerment of farmers, along with technical solutions and product manufacturing, can assist in addressing this issue.

Overall, crop residue burning is a significant contributor to India's air pollution crisis, and addressing this issue through sustainable practices and government initiatives is crucial for improving air quality and public health in the country.

Poor enforcement of anti-pollution laws

India has long struggled with air pollution, which has emerged as a serious environmental issue. In 2019, India was the world's second most polluted country, with 21 of the 30 most polluted cities in the world. The country's air pollution is caused by a range of factors, including industrial and vehicular emissions, construction dust, waste burning, and the use of traditional fuels such as fuelwood, agricultural waste, and biomass cakes for cooking and heating.

While India has implemented various initiatives and policies to combat air pollution, such as the National Clean Air Programme (NCAP) launched in 2019, the enforcement of these anti-pollution laws has been poor. This is due to a variety of factors, including weak state capacity, inadequate legal authority, and corruption.

One critical constraint is the Indian government's weak state capacity, or its ability to design, implement, and enforce rules and policies. While India has strong environmental laws on paper, the institutions responsible for implementation are often immature or ineffective. The pollution control boards (PCBs) in India, for instance, lack the financial and administrative capacity to adequately address pollution issues.

In addition, the enforcement of anti-pollution laws is further complicated by the federal nature of the air quality problem, which requires coordination between various state governments and the central government. This coordination is particularly challenging when it comes to issues such as crop burning, where the potential political costs of enforcing strict laws might not be borne by the ruling party.

Moreover, corruption is prevalent in the construction industry, making it difficult to regulate and enforce anti-pollution measures. Contractors are often required to implement dust control measures, such as spraying water and cordoning off construction areas, but these measures are not always effectively enforced.

The poor enforcement of anti-pollution laws has had severe consequences for public health in India. According to a Lancet study, nearly 1.67 million deaths and an estimated loss of US$28.8 billion in output were attributed to worsening air pollution in 2019. The availability of timely and accessible air pollution data is also limited, hindering the ability to address the issue effectively.

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