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What causes pollution in the air? 9 definitive reasons for air pollution!

    Do you want to know what causes pollution in the air and why we should be so concerned about it? Then you have come to the right place! In this article I teach you all about what causes pollution in the air and what you can do to help…

    What causes pollution in the air?

    Climate change, sustainability, global warming… these are words and phrases you hear on a regular basis these days, and for good reason. Over the years, human activity has caused irreversible damage to the planet we call home, and we need to act fast in order to try and prevent further damage from occurring in the future. One type of climate damage we need to look at is air pollution, and in today’s article I’ll be looking at exactly what causes pollution in the air – and what we can do about it…

    What is air pollution?

    What causes pollution in the air? 9 definitive reasons for air pollution!

    Air pollution refers to the air being filled with dangerous substances, which come from natural and man-made sources.

    According to the World Health Organisation, ‘almost all of the global population (99%) breathe air that exceeds WHO guideline limits and contains high levels of pollutants, with low- and middle-income countries suffering from the highest exposures.

    Air quality is closely linked to the earth’s climate and ecosystems globally. Many of the drivers of air pollution (i.e. combustion of fossil fuels) are also sources of greenhouse gas emissions. Policies to reduce air pollution, therefore, offer a win-win strategy for both climate and health, lowering the burden of disease attributable to air pollution, as well as contributing to the near- and long-term mitigation of climate change’.

    Why is it important to combat air pollution?

    Air pollution is bad for the planet and for our health. In all forms, air pollution is said to cause around 6.5 million global deaths per year – pollutants get into our bodies and cause cell inflammation, which then leads to respiratory disease and various types of cancer among other illnesses. Children are particularly impacted by air pollution, as are people who live in rural areas.

    Preventing premature deaths and ensuring people have good health and well-being are all part of the United Nations’ 17 Sustainable Development Goals – they also have goals aimed at climate action and life on land. These goals were put in place to work towards a thriving planet populated by healthy and happy individuals living safe, sustained and long lives. Combating what causes pollution in the air will go some way to helping achieve these goals!

    What causes pollution in the air?

    What causes pollution in the air? 9 definitive reasons for air pollution!

    There are said to be 9+ causes of air pollution; some are, of course, more damaging than others – and they won’t all be found in the same places. The air in the countryside will see a different type of pollution than city air, for example. But all of what causes pollution in the air is dangerous and needs to be addressed at some level. Below, I’ll dive into nine of the major causes of air pollution and what we might be able to do about them.

    Burning fossil fuels

    You will likely already know about the damage caused by burning fossil fuels, and it is one of the leading problems when it comes to what causes pollution in the air. When coal, oil and gas is burned to produce energy for transport and electricity purposes, it comes with a harmful byproduct: CO2. They also lead to the release of nitrogen oxides, mercury, dust, sulphur dioxide and more. In turn, all of this results in smog, acid rain, and dirty/smelly air – when inhaled, this can limit the heart’s ability to pump enough oxygen around the body. This is where illness comes into play!

    This is why there is such a focus on clean and renewable energy currently – it is really important if we want a healthy and sustainable planet.

    Industrial emissions 

    Since the industrial revolution, our planet has been suffering the effects of industrial emissions – if we are looking at what causes pollution in the air, this is another strong example. This refers to any sort of emission which comes from industry production; fossil fuels are one example, alongside emissions related to waste management, livestock rearing, and much more. 

    What causes pollution in the air? 9 definitive reasons for air pollution!

    Limits have been put in place for businesses in many countries to say how many emissions they are allowed to be responsible for per year; these limits apply to businesses like petrol stations, foundries, car manufacturing plants and more. Following these limits, as well as working towards processes which don’t emit such harmful pollutants, is really important.

    Indoor air pollution

    It’s not just the outdoors we need to think of – in terms of what causes pollution in the air, we also need to think about what goes on inside. Polluted air isn’t just about smog and gas, but also more tangible things. If somebody is smoking a cigarette indoors, the air in that room or building becomes polluted. Other examples include toxic cleaning products, poor ventilation, wood stoves and so on. Anything which negatively changes the make up of the air is technically classed as air pollution, and it can come from really small and simple things which we might not even consider.

    According to Asthma + Lung UK, ‘anyone can be affected by indoor air pollution. If you live with a lung condition, such as COPD, asthma, or bronchiectasis, you’re more likely to be affected by poor air quality as your lungs are more sensitive – although not everyone has the same reactions to the dust, dirt and gases in our homes. 

    If you have a severe lung condition you might find it harder to move around, so may spend more time indoors. This means you may have more contact with things that affect the air you breathe indoors. These could include cigarette smoke, cleaning products or mould.

    Children are particularly vulnerable to poor indoor air quality as their lungs are still developing. Children’s airways are smaller, so inflammation caused by indoor and outdoor air pollution can cause them to narrow more easily than in older people’.

    Switching to eco-friendly cleaning products, and not smoking indoors, are both great ways to reduce indoor air pollution.

    Microbial Decaying Process

    Have you heard of the microbial decaying process? Chances are you might not have done, but it’s quite simple to wrap your head around. It refers to decomposition, and it definitely needs to be considered when we talk about what causes pollution in the air. Essentially, if we didn’t have microbes (these tiny, tiny living things which require a microscope to even be seen…) then our planet would be overrun with corpses. A scary thought, right? Microbes work really hard to break down dead plant or animal matter, and they recycle it into phosphorus, carbon and nitrogen among other substances.

    But when these microbes start naturally decaying living organisms, we experience air pollution from them – particularly due to the release of methane gas.

    Burning of waste

    What causes pollution in the air? 9 definitive reasons for air pollution!

    When there are poor waste management systems in place, people end up needing to burn rubbish before they essentially become buried under trash. Delhi in India is a sad example of this, and other places with a high level of poverty are much the same. When this rubbish and waste is burned instead of being properly disposed of, toxins are released into the air – this is a major player in terms of what causes pollution in the air.

    Soot, carcinogens and black carbon are all released; this is bad enough in the long term, but in the short term it can cause major skin irritation, breathing difficulties, headaches, nausea and more.


    Staying on the topic of fires when we look at what causes pollution in the air, wildfires are terrible for this. Wildfires are devastating in so many ways, causing loss of life as well as damaging property and income sources across the globe every year. And as the climate changes and our planet gets hotter, they are only becoming more and more common. Some of the worst we’ve seen in recent years have been in Greece, Australia, California, Russia and Canada.

    In terms of air pollution, wildfires create a lot of smog; often it is farmland which is being burned, and agricultural waste causes a lot of further pollution when it burns. The smog makes it difficult to breathe, and also hard to see which can cause accidents – the impact of a wildfire is felt for a long while after the blaze has been brought under control.


    Transport is probably one of the things which springs to mind straight away when you consider what causes pollution in the air; planes, cars, buses, lorries and so on all cause high levels of air pollution. Let’s just look at cars for now – your car releases many harmful substances such as particulate matter, carbon monoxide, hydrocarbons and nitrogen oxide every time you drive it. And when you think about how many millions of cars are on the roads in cities and suburbs across the world, it is no wonder that our air is so polluted…

    Air quality is measured at local levels, and some areas have put zones in place to ensure they are able to try and reduce the amount of air pollution caused by cars and other vehicles on the road. London, for example, has a ‘congestion charge zone’ where you are charged for driving in certain areas. This £15 daily charge is to encourage people to avoid using their cars here so they can improve the air quality.

    If everybody looked at their own driving habits, we would begin to see an increase in air quality. Carpooling (sharing cars when driving to work, for example) or using public transport instead of your car is a great way to positively impact the current levels of air pollution. 

    On a larger scale, the production of electric cars is increasing rapidly with some countries vowing to do away with petrol/diesel/gas-powered vehicles entirely in the near future. Following on from that, the air travel industry is continuing with their research into, and implementation of, sustainable aviation fuels.

    Agricultural activities 

    What causes pollution in the air? 9 definitive reasons for air pollution!

    Another one to add to the list of what causes air pollution is any form of agricultural activity. Air quality in rural and farming areas is notoriously low; fertilisers and pesticides are used to encourage crops to grow, for example, but they mix with the air and the rain and get carried on the wind, causing air pollution. These substances are bad for the quality of the air, and when ingested are dangerous to both humans and animals.

    Of course, agricultural waste is often burned too – as mentioned earlier, burning waste is one of the other biggest causes of air pollution. With the banning of pesticides and better waste management systems in place, hopefully agriculture will have less of an impact on our air pollution levels in the future.

    Animals themselves contribute to what causes air pollution when they are farmed. According to FAIRR, farming livestock contributes approximately 6 billion tons of greenhouse gases to our atmosphere every year. By cutting down on meat, there will be less demand for animal products and in turn less impact from farming…

    Construction and demolition

    Two more causes of air pollution are both construction and demolition. These two processes cause a lot of particulate matter to be released into the air, as well as a lot of dust. These issues are generally only temporary, but they are still hazardous (especially for children and the elderly) because of the haze they create which leads to both reduced vision and difficulty breathing. 

    Air quality control is important at building sites, and again there are certain limits and standard construction companies must abide by when doing their work. 

    What causes pollution in the air? To sum up

    When it comes to what causes pollution in the air, you can see that there are plenty of culprits. If you enjoyed learning about how our air quality has decreased over time, and how we can perhaps start to change this, you might enjoy the following blog posts from me…