Air Pollution: Past Efforts, Present Results

Air pollution is a pressing issue that has been detrimental to human health and the planet, causing approximately seven million deaths annually. While the Industrial Revolution in the 1800s brought about a significant increase in pollution, it was not until the mid-1900s that public awareness and efforts to combat air pollution gained momentum. Since then, various steps have been taken worldwide to address this issue, with notable actions including the implementation of the Clean Air Act in the United States in 1970, which has helped reduce harmful emissions from transportation, power plants, and manufacturing. Europe and North America also took steps to control and reduce emissions of sulphur and nitrogen oxide in the latter half of the 20th century. Despite these efforts, air pollution remains a significant challenge, with modern societies still heavily reliant on polluting activities and energy sources.

The US Clean Air Act, 1970

The US Clean Air Act, established in 1970, has been pivotal in reducing air pollution in the country. It is the primary federal air quality law in the US, aimed at reducing and controlling air pollution on a national scale. The Act has undergone several amendments since its inception, with significant changes in 1977 and 1990, building upon the earlier Clean Air Acts of 1963 and 1970.

The 1970 Clean Air Act played a crucial role in addressing the public health and welfare risks posed by hazardous air pollutants. It authorised the US Environmental Protection Agency (EPA), established in 1970, to regulate emissions and safeguard public health. The EPA was tasked with determining the most significant air pollutants and setting National Ambient Air Quality Standards (NAAQS) to govern the acceptable levels of these pollutants in the ambient air. This marked a shift in the federal government's role in air pollution control, with the EPA developing extensive regulations and programs to implement the law's mandates.

The Act also required states to develop State Implementation Plans (SIPs) to outline their strategies for achieving the NAAQS by 1977. These plans considered local conditions, such as geography, industrial activity, transportation, and housing patterns, allowing for a cooperative federal model between the EPA and state governments. The EPA provided approval for each SIP, ensuring that states met the national minimum criteria.

The Clean Air Act of 1970 had a significant impact on reducing emissions from transportation, power plants, and manufacturing. Notably, the EPA's early actions included eliminating lead from US gasoline, a milestone achievement in public health. The Act also provided the EPA with enforcement authority, allowing for the maintenance and improvement of air quality over time.

While the Clean Air Act has been instrumental in reducing air pollution, challenges remain. The transition to cleaner fuels and industrial processes is crucial to effectively controlling air pollution and mitigating its health and environmental impacts. Additionally, addressing climate change-fueled wildfires and extreme heat is essential to protect public health and reduce air pollution in vulnerable communities.

Sulphur and nitrogen oxide emission control

Sulphur and nitrogen oxides are two of the six common air pollutants, known as criteria pollutants, which are subject to primary and secondary National Ambient Air Quality Standards under the federal Clean Air Act. Sulphur dioxide (SO2) is a toxic gas emitted during the burning of fossil fuels or other materials containing sulphur. It is harmful to human health and the environment, contributing to respiratory illness and damaging trees, plants, and sensitive ecosystems.

Nitrogen oxides (NOx) are primarily emitted as nitric oxide (NO) and, to a lesser extent, nitrogen dioxide (NO2). These pollutants are also harmful to human health and the environment, and they are predominantly emitted by power stations and motor vehicles.

Sulphur Oxide Emission Control

Sulphur oxide emissions have been addressed through various methods:

• Fluidized Bed Combustion: This technique involves burning crushed coal in a bed of limestone or dolomite particles, which absorb sulphur released during combustion, forming CaSOx. This process reduces sulphur oxide and nitrogen emissions while increasing efficiency and decreasing the size and weight of the boiler.
• Clean Gaseous Fuel: In some industries, a clean dust-free gaseous fuel is produced by gasifying coal with steam and air. While this method does not remove all sulphur, it reduces the amount of sulphur oxide pollution compared to burning coal directly.
• Federal Regulations for Diesel Fuels: Regulations have been implemented to reduce the sulphur content in diesel fuels, leading to significantly lower sulphur oxide emissions from diesel vehicles and equipment.
• European Emission Control Areas: The establishment of these areas, particularly in the North and Baltic Seas, has helped reduce sulphur oxide emissions near ports. However, compliance rates are lower in open waters, and nitrogen oxide emissions have increased.

Nitrogen Oxide Emission Control

Nitrogen oxide emissions have been a challenge to control due to the increasing number of road vehicles. However, some measures have been effective:

• Use of Gas in Electricity Generation: In the early 1990s, the shift from coal and oil to gas in electricity generation resulted in a significant reduction in nitrogen oxide emissions from the sector until 2000.
• Improved Fuel and Power Stations: The use of cleaner fuel and more modern power stations has contributed to lowering nitrogen oxide emissions.

Anti-pollution demonstrations

Air pollution is a pressing environmental issue, and countries have taken action to tackle it. However, despite some progress, it remains a significant concern.

One notable example of action taken against air pollution is the Clean Air Act, enacted in the United States in 1970. This legislation empowers the Environmental Protection Agency (EPA) to regulate harmful air pollutant emissions, safeguarding public health. This has successfully reduced emissions from transportation, power plants, and manufacturing. However, challenges such as wildfires and extreme heat, exacerbated by climate change, have emerged, affecting air quality.

While historical efforts are significant, they are insufficient to address the current magnitude of the problem. The transition to cleaner fuels and industrial processes is essential to effectively control air pollution. This includes adopting renewable energy sources, improving fuel efficiency, and transitioning to electric vehicles.

To accelerate progress, anti-pollution demonstrations and protests have played a pivotal role in advocating for change. Greenpeace, an environmental organization, has been at the forefront of many of these efforts. Here are some examples of their initiatives:

• Greenpeace Thailand: Collaborating with EnLaw, EARTH, BioThai, and other organizations, Greenpeace Thailand urged the Thai government to address the country's air pollution problem, specifically targeting PM2.5 levels. They are also involved in the Thailand Solar Fund project, promoting solar panels on hospital rooftops and supporting renewable energy.
• Greenpeace Romania: Activists from Greenpeace Romania protested in Bucharest, specifically targeting critical sectors contributing to high pollution rates: energy, construction, waste, and traffic.
• Greenpeace Africa: In Dakar, Senegal, Greenpeace volunteers demanded clean air, drawing attention to the health impacts of air pollution from fossil fuels, which cause approximately 4.5 million deaths annually. During a cricket match between England and South Africa, activists delivered air pollution masks to the Proteas captain and unfurled a banner stating, "Toxic air is not just a game #BowlOutAirPollution."
• Protests in the United Kingdom: Protests have occurred across the UK, with surfers, families, and other citizens expressing their discontent with water companies due to poisoned drinking water and polluted lakes. Demonstrations have also taken place to oppose sewage discharges into English seas and rivers, with thousands of protesters joining a march in London for clean water.
• Protests in the Netherlands: Farmers in the Netherlands voiced their opposition to the government's plan to tackle nitrogen pollution, which included significant reductions in the numbers of pigs, cattle, and chickens.

These demonstrations and protests reflect a global awareness of the urgency to address air pollution and the detrimental impacts it has on human health, the environment, and the economy. They serve as a catalyst for change, urging governments and industries to implement more sustainable practices and policies.

Transition to cleaner fuels

Transitioning to cleaner fuels and industrial processes is the most effective way to control air pollution. This involves switching to renewable energy sources such as wind and solar power, improving fuel efficiency in vehicles, and replacing gasoline-powered cars and trucks with electric vehicles. This approach not only limits air pollution at its source but also helps curb global warming, thereby mitigating the worst health impacts of air pollution.

In the United States, the Clean Air Act has played a crucial role in reducing air pollution since its passage in 1970. Despite attempts by fossil fuel interests and industry-friendly lawmakers to weaken its protections, the Act has driven significant progress in improving air quality. For instance, new passenger vehicles today are 98-99% cleaner for most tailpipe pollutants compared to the 1960s. Fuels have also become much cleaner, with lead eliminated and sulfur levels reduced by more than 90%.

The Clean Air Act has spurred the deployment of clean technologies and innovations that reduce emissions and control costs. Power plants, in particular, have made substantial cuts in emissions that cause acid rain and harm public health. Additionally, mobile and industrial pollution sources release far less toxic pollution than they did in 1990.

The transportation sector, a major source of carbon pollution, has also seen significant improvements. The Environmental Protection Agency (EPA) has set carbon emissions standards for passenger cars, trucks, and buses, leading to the development and implementation of technologies such as the automotive catalytic converter. These standards have resulted in cleaner vehicles, with new cars, SUVs, and pickup trucks being roughly 99% cleaner for common pollutants like hydrocarbons, carbon monoxide, nitrogen oxides, and particle emissions compared to 1970 models.

To further reduce air pollution from transportation, individuals can also make conscious choices. Driving less, carpooling, biking, using public transportation, and transitioning to electric vehicles are all effective ways to decrease vehicle exhaust, a major source of air pollution. Additionally, proper vehicle maintenance, such as fixing exhaust and oxygen sensor problems and maintaining correct tire pressure, can help reduce pollution.

EPA standards for aircraft

Air pollution is one of the most pressing environmental issues in the world today, and it has been a concern for several centuries. The Industrial Revolution, which began in the early 19th century, marked a significant shift towards new manufacturing processes, chemical manufacturing, iron production, and increased use of steam engines. This transition led to a rise in air pollution, particularly in Great Britain, other European countries, and the United States.

In the 20th century, Europe and North America were the most affected by air pollution due to their high emissions of sulphur and nitrogen oxide. However, the second half of the century saw a profound economic transformation in Asia, with several countries becoming global economic leaders. As a result, Asia now accounts for nearly 40% of the global economy, and Central, East, and South Asia have overtaken North America and Europe in terms of emissions.

Despite these challenges, efforts have been made to address air pollution. The Clean Air Act, established in 1970 in the United States, authorizes the Environmental Protection Agency (EPA) to regulate harmful air pollutants and protect public health. This Act has been successful in reducing emissions from transportation, power plants, and manufacturing. Additionally, there has been a 90% decline in SO2 emissions in Europe and North America since their peak in the 1970s.

To address air pollution from aircraft specifically, the EPA has implemented several standards and regulations:

• The EPA has finalized greenhouse gas (GHG) emission standards for airplanes used in commercial aviation and large business jets. These standards align with the international carbon dioxide (CO2) emissions standards set by the International Civil Aviation Organization (ICAO). Aircraft covered by this rule contribute to 10% of all transportation GHG emissions and 3% of total US GHG emissions.
• The EPA collaborated with the National Highway Traffic Safety Administration (NHTSA) to enable the production of a new generation of clean vehicles, including aircraft, by reducing GHG emissions and improving fuel efficiency.
• The EPA proposed findings that GHG emissions from certain classes of engines used in aircraft contribute to air pollution, endangering public health and welfare under Section 231(a) of the Clean Air Act. This was a step towards adopting GHG standards and setting international CO2 emissions standards for aircraft.
• The EPA has been working with the ICAO to find the best way to regulate CO2 emissions from airplanes and collaborate on international air pollution standards for aircraft.

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