The History of Air Pollution: How Air Quality Has Changed Since 400BC

Did you know every breath you take affects the air around you? 

As long as there have been humans, we’ve impacted the air around us. Just breathing, you’re releasing 500L of carbon dioxide (CO2) into the atmosphere. And that’s not including any other activities we engage in. 

Throughout history, air quality has become increasingly important.  

While it’s not always visible, we’ve made it easier to understand as our technology has evolved to monitor air quality better. In this week’s blog, we wanted to explore the history of air pollution around the world and how far we’ve come—from laws in Ancient Rome to modern air quality policies. 

How Older Civilizations Tackled Air Pollution 

While air pollution has been a topic of discussion for many years, it would be easy to think that it is a relatively modern problem. Unfortunately, that isn’t true. Air pollution has been a problem throughout history for many reasons.  

Let’s look at what air pollution has looked like throughout time, starting with Ancient Roman.  

400 BC

Air pollution was an issue that Romans experienced—the smoke they experienced was often referred to as gravioris caeli (“heavy heaven”) and infamis aer (“infamous air”).

Philosopher and statesman, Seneca, wrote, “No sooner had I left behind the oppressive atmosphere of the city and that reek of smoking cookers which pour out, along with clouds of ashes, all the poisonous fumes they’ve accumulated in their interiors whenever they’re started up, than I noticed the change in my condition.”  

Stephen Mosley, a lecturer at the School of Cultural Studies at Leeds Metropolitan University, even noted that the Roman courts considered civil claims over smoke pollution 2,000 years ago. For example, the jurist Aristo declared that a local cheese shop couldn’t expel smoke into buildings above it and the fumes were bothering residents. 

Later, in 535, the Roman empire even created early clean air policies. Emperor Justinian proclaimed clean air’s importance as a birthright and stated, “By the law of nature, these things are common to mankind—the air, running water, the sea.”  


Even pre-industrialized London saw the negative impacts of burning coal and the increased development of smog in the 1200s. With the growth of cities came a higher demand for coal as a fuel source—drastically impacting air pollution.

Today, there is still a strong misconception that air quality is only a recent problem, even though we’ve seen it’s been an issue long before that. 


When Europeans left the continent for the New World, they also brought air pollution. In 1572, Spanish conquistadors started mining silver in what is now Bolivia, and they used a technique that grinds ore into powder which shot lead plumes into the air 

Centuries later, researchers at Ohio State University discovered the dust in ice cores from Peru. This provided evidence that air pollution due to human impact was widespread long before the Industrial Revolution. 


By the 1600s, smoke from burning coal was causing damage to the architecture in London and other major cities. The invention and eventual widespread use of the steam engine further accelerated air pollution.  

Large industrial cities began pumping vast pollution into the atmosphere. The concentration of particulate matter also rose dramatically in London between 1760 and 1830. With the industrial revolution more people flocked to cities which contributed to air pollution in those areas. 

In 1800, there were only 6 cities worldwide with a population of more than 500,000 people. But by 1900, there were 43 cities. Residents of emerging industrial hubs soon felt the acrid smoke sting their eyes and impact their breathing. Air pollution continued to rise in the 1800s, causing respiratory illness and higher death ratesparticularly in areas that burned more coal.  

How Recent Civilizations Tackled Air Pollution 

Next, let’s talk about air pollution in the last 100 years. More recently, a lot has changed around the world when it comes to air quality monitoring. And that’s because of a lot of different factors, like industrial accidents and the increasing knowledge about how air pollution impacts our health. 

Now, many countries are focused on how they can reduce air pollution in their communities. 


On March 18, 1937, a gas explosion killed almost 300 students and teachers at a school in New London, Texas. The school was a new steel-and-concrete building, one of the wealthiest in the country.

Yet, it was reduced to rubble because no one was alerted of the danger building in the basement—a simple gas leak. 

At the time, the school was heated by tapping into a local gas company’s residue gas line, a common money-saving practice. Unfortunately, a faulty connection caused a leak of the gas. It filled the basement undetected before it was ignited by a maintenance employee, causing the catastrophic explosion. 

This incident resulted in the mandated use of mal odorants to be added to all natural gas for commercial and industrial use. Today, mercaptan is a harmless chemical that is used to give the gas its distinctive rotten egg odor.  


In the early 1940s, a new polluter contributed to the decreasing air quality—automobiles. By 1940, the city of Los Angeles had more than a million cars. However, no one realized the effect of exhaust on air quality at the time.  

Because of this lack of understanding, many residents feared the new smog they were experiencing in July of 1943 resulted from a chemical attack. Four years later, they established the country’s first air pollution control district and California went on to become a leader in regulating air pollution. 

1950s Onwards 

In October 1948, the city of Donora, Pennsylvania, was impacted by heavy smog that resulted in 20 deaths and 6,000 becoming sick. Across the world, in December of 1953, a thick smog also took over London—killing 4,000 people. 

Both countries reacted with strong air quality policies. The Air Pollution Control Act was established in the US in 1955 and provided funds for research and technical support on the scope and sources of air pollution in the US.  

Then, the Clean Air Act was established in 1965 in the UK and aimed at reducing pollution due to smoke. Smoke-free areas were established throughout the city of London, burning coal was restricted, and homeowners were offered grants for switching heating sources.  

In 1961, a National Survey was established in the UK and was the world’s first coordinated national air pollution monitoring network. It kept track of black smoke and sulfur dioxide at 1200 sites across the UK. Then in 1987, the World Health Organization established  Air Quality Guidelines for Europe which addressed acceptable values of 28 air pollutants. 

Of course, air pollution wasn’t only an issue in North America and Europe.  

Back in 1958 was the beginning of Mao’s Great Leap Forward, where he planned to completely industrialize China in the span of only 5 years.

After 3 years, it came to an endbut the environmental damage had already been done. Despite the failure, it set the country on the track toward industrialization and China’s air pollution suffered as a result.  

So, What’s the Lesson in All of This? 

Well, air pollution is not a new problem. We’ve had a problem with it ever since we collected in cities and started using tools to improve our quality of life. While coal, cars, and natural gas have given many new luxuries in the modern world—it comes at a cost. 

Thankfully, there are communities and organizations working to reduce air pollution through things like air quality monitoring. At PurpleAir, we’ve made it our mission to help make air quality data accessible to all, so we can see the big picture and make better decisions for our communities. 

Worried About Your Air Quality?  

Monitor the particulate Matter levels around the world with our free, real-time PurpleAir Map or join PurpleAir's mission to make air quality data accessible to everyone by investing in an air quality monitor for your home.  

Together, we can be informed and make changes in our daily habits and the community to improve air quality.