Air Pollution Awareness: A Historical Perspective

Air pollution has been a problem for thousands of years, with the ancient Romans referring to their city's smoke cloud as infamous air. However, it was not until the Industrial Revolution that outdoor air pollution started to become a significant issue, particularly in Britain and Northern Europe, due to the large-scale burning of coal. In the 1940s, Los Angeles, with its million-plus cars, experienced its first smog incident, which residents feared was a Japanese chemical attack. This was followed by smog incidents in Donora, Pennsylvania in 1948, and London in 1952, which led to the passing of the Clean Air Act in 1956 in the UK and 1963 in the US. In the 1960s, acid rain was identified as the number one air-related issue, and scientists began investigating the causes, finding a clear link to pollutants such as sulphur and nitrogen oxide.

Air pollution has been a concern since ancient times

Ancient Romans were dealing with smog, with residents of ancient Rome complaining about the city's noxious smoke cloud, which they referred to as "gravioris caeli" ("heavy heaven") and "infamis aer" ("infamous air"). The philosopher and statesman Seneca wrote about the negative effects of Rome's air pollution, and the ancient Roman justice system also got involved, with the jurist Aristo declaring that a cheese shop could not discharge smoke into the buildings above it.

In the New Stone Age, people who carved flint from limestone in stone mines may have suffered from silicosis due to breathing in stone powder all day. Lead poisoning has also been detected in hominids who lived about 200,000 years ago in what is now Zambia, caused by lead seeping from a nearby seam into their water source.

In the 1280s, there were complaints about smoke from burning coal in London, and attempts to ban burning during the reign of Queen Elizabeth I failed. In the 16th century, Spanish conquistadors mining silver in what is now Bolivia used amalgamation, a technique that released lead plumes into the air.

By 1940, Los Angeles had more than a million cars, and on July 26, 1943, the city experienced a smog incident that residents feared was a Japanese chemical attack. This led to the establishment of the first air pollution control district in the country four years later. In 1963, the US Congress enacted the first Clean Air Act, and national emissions standards for cars were set two years later.

While air pollution has been a concern for millennia, the Industrial Revolution accelerated the magnitude of emissions and the geographical spread of contributing countries, with highly polluted cities becoming the defining issue.

Industrial Revolution accelerated air pollution

Air pollution has been recognised as a threat to human health since as early as 400 BC, when it was discussed by Hippocrates. The Industrial Revolution, which began in the late 18th century, accelerated the magnitude of emissions of primary pollutants and the geographical spread of contributing countries. The shift to a manufacturing-based economy led to increased production and efficiency, and advanced transportation systems. This progress came at a cost, as the Industrial Revolution also marked the start of our intensive use of fossil fuels, which has driven climate change and global warming.

The Industrial Revolution introduced electricity, steel production, and the internal combustion engine, driving mass production and the growth of heavy industries. This led to exponential increases in energy consumption and resource extraction, with each phase of industrialisation adding to the cumulative environmental strain. As a result, there were significant increases in air pollution, deforestation, and greenhouse gas emissions, particularly carbon dioxide (CO2). Over the entire industrial era, approximately 2.3 trillion tonnes of CO2 were released into the atmosphere, with human activities currently releasing over 30 billion tonnes of CO2 annually.

The widespread adoption of coal, oil, and later natural gas, fuelled the growth of industries, but it also contributed to the ongoing environmental crisis. As machinery and technology advanced, emissions grew, and continue to grow, causing climate change that is now difficult to reverse. The Industrial Revolution set a precedent for industrial practices that continue today, with global emissions dominated by East and South Asia in the early 21st century.

The effects of air pollution on human health have been well-documented, with constant exposure to polluted environments increasing the risk of developing health issues and premature death. This has been referred to as a "silent public health emergency" by the Head of the World Health Organisation, and has been observed in the accelerated forest loss across several European countries, including the Czech Republic, Poland, and Germany.

Air pollution and its health impacts

Air pollution has been recognised as a threat to human health since as early as 400 BC. Written accounts from the eighteenth century onwards show the growing scale of poor air quality in urban centres and industrial areas. The Industrial Revolution accelerated the magnitude of emissions and the geographical spread of contributing countries, with highly polluted cities becoming a defining issue.

The harmful effects of air pollution were also observed in Roman times, with residents of ancient Rome referring to the smoke cloud over their city as "gravioris caeli" ("heavy heaven") or "infamis aer" ("infamous air"). The philosopher and statesman Seneca wrote of the "oppressive atmosphere" and "poisonous fumes" of Rome.

In the 1940s, Los Angeles, with its over one million cars, experienced its first smog incident, which residents feared was a Japanese chemical attack. This led to the establishment of California's first air pollution control district. In 1963, the United States Congress enacted the first Clean Air Act, and two years later, national emissions standards for cars were set.

Air pollution is the presence of contaminants in the atmosphere, such as dust, fumes, gas, mist, odour, smoke, or vapour, in quantities that can be harmful to human health. The main pathway of exposure is through the respiratory tract, leading to inflammation, oxidative stress, immunosuppression, and mutagenicity in cells throughout the body, impacting the lungs, heart, and brain, among other organs. Fine particulate matter, or particle pollution, is a critical pollutant that leads to negative health impacts. These fine particles can penetrate deep into the lungs and even enter the bloodstream, affecting other organs. Short-term spikes in fine particle pollution can be deadly, and researchers estimate that PM2.5 is responsible for over 50,000 premature deaths in the United States annually.

Ozone, another pollutant, is a powerful lung irritant that can cause inflammation and damage to the respiratory system. High ozone levels can cause breathing problems such as chest tightness, coughing, and shortness of breath, even in healthy young adults.

Air pollution has also been linked to deforestation and the loss of biodiversity. In the 1980s, experts noticed accelerated forest loss across several European countries, with a particular impact on the health of forests in the Czech Republic, Poland, and Germany. This prompted the scientific community to investigate the link between worsening air quality and deforestation.

Today, air pollution is recognised as the worst pollution-related epidemic in the world, responsible for at least seven million deaths every year. Constant exposure to polluted environments increases the risk of developing health issues and premature death.

The rise of cities and air pollution

Air pollution has been a concern since the time of Hippocrates, around 400 BC. Written accounts from the following two millennia also discuss air pollution, and from the 18th century onwards, measurements show the scale of poor air quality in urban centres.

The rise of cities is closely linked to the growth of industry and manufacturing, which in turn has led to increased air pollution. The Industrial Revolution, which began around 1820, saw the emergence of new manufacturing processes, including the mechanised factory system, chemical manufacturing, and iron production. This transition led to an increase in emissions and pollutants, with cities becoming hotspots of poor air quality.

As cities expanded and industrial activities intensified, the magnitude of air pollution escalated. The burning of coal, the use of steam power, and the growing number of automobiles all contributed to the deteriorating air quality in urban areas. By the 1940s, the negative impacts of exhaust fumes from automobiles became evident when Los Angeles experienced its first smog incident. This prompted the establishment of the first air pollution control district in the United States.

The issue of air pollution continued to gain attention in the following decades, with the enactment of the Clean Air Act in 1963 and the setting of national emissions standards for cars in 1965 in the United States. However, cities remained heavily affected by poor air quality, and the problem extended beyond local boundaries. Acid rain, a consequence of air pollution, became a pressing environmental issue in the 1960s and 1970s, affecting North America and Europe. The long-range transport of pollutants, such as sulphur and nitrogen oxide, from power plants contributed to this issue.

Today, air pollution remains a significant concern, particularly in low- and middle-income cities. According to the World Health Organization (WHO), more than 80% of people living in urban areas that monitor air pollution are exposed to air quality levels that exceed WHO guidelines. The rise in outdoor air pollution is linked to various sources, including transport, industry, construction, farming, and wood-burning in homes. As a result, the health risks associated with air pollution are substantial, including respiratory diseases, heart disease, lung cancer, and asthma.

To address these issues, cities have implemented various strategies, including reducing industrial smokestack emissions, transitioning to renewable energy sources, and promoting sustainable modes of transportation. While progress has been made in some regions, air pollution continues to rise at an alarming rate in many parts of the world, particularly in fast-growing cities in the developing world.

Global efforts to control air pollution

Air pollution has been recognised as a threat to human health since as early as 400 BC. The Industrial Revolution accelerated the magnitude of emissions of primary pollutants, and highly polluted cities became the defining issue. The Great Smog of London in 1952 was a culmination of this.

Since the mid-20th century, there have been increasing global efforts to control air pollution. The Clean Air Act was enacted in the US in 1963, and national emissions standards for cars were set two years later. California has been a leader in regulating air pollution, and Los Angeles, which was smogged in 1943, established the first air pollution control district in the country. The US EPA has also been instrumental in reducing air pollution, with the Clean Air Act Amendments of 1990 achieving large health benefits, and a 2011 report finding that pollution reductions under the Act prevented 205,000 early deaths in 1990 alone.

In Europe, acid rain became the number one air-related issue in the 1960s and 1970s. It was found to be a direct consequence of air pollution, affecting the environment and contributing to the loss of biodiversity. This discovery led many countries to step up their efforts to reduce emissions, and an international framework was instituted: the 1979 Convention on Long-range Transboundary Air Pollution. Europe and North America took important steps to control and reduce emissions of sulphur and nitrogen oxide.

The Climate and Clean Air Coalition (CCAC) is a global network created in 2012, which includes governments, intergovernmental organisations, businesses, scientific institutions and civil society organisations. The Coalition helps partners create policies and practices to deliver substantial reductions in short-lived climate pollutant emissions. The CCAC promotes measures such as replacing wood stoves and burners with pellet stoves, banning open-field burning of agricultural waste, and recovering and using fugitive emissions during oil and natural gas production.

The World Health Organisation (WHO) also plays a role in global efforts to control air pollution. The WHO Global Air Quality Guidelines (AQG) offer global guidance on thresholds and limits for key air pollutants that pose health risks. The guidelines also provide interim targets to promote a gradual shift from high to lower concentrations, with associated health benefits.

In addition, there are local initiatives to address air pollution. In Nigeria, the Rural Women for Energy Security (RUWES) is a group of over 2 million women working to protect themselves and their families from dangerous air pollution by creating clean energy enterprises and providing affordable clean energy solutions.

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