Why is the air polluted?

Air pollution is a global problem that is increasingly coming to the fore. Why is the air polluted in the first place and how does it happen?

In a nutshell,air is polluted by solid and liquid particles (plus some gases) suspended in the air. The origin of these particles is varied and can come from exhaust gases, vehicles, pollen, industry, firewood, mold, volcanoes and forest fires. These suspended particles in the air are called aerosols and they are the cause of polluted air both here and elsewhere in the world.

In the following, we will take a closer look at why and how air pollution occurs, what are the main pollutants and what consequences can polluted air have on us.

Causes of air pollution

Any particle that enters the air or is formed as a result of chemical reactions can be an aerosol. A large number of these aerosols enter the atmosphere during the burning of fossil fuels (example: coal, oil and wood). Other common sources of aerosols are car and factory exhaust, fires, molds, dust and pollen. These particles can originate directly from these sources, or (as mentioned earlier) result from certain chemical reactions in the air. This type of pollutant is called PM particles.

At the beginning of the article, we mentioned that certain gases can also be the cause of air pollution. The most widespread example of this is ozone, which is a particularly big problem and one of the main sources of pollution in cities. We know two types of ozone: "good" ozone and "bad" ozone - depending on where it is located in our atmosphere. We all know that good ozone, which is located high above us and protects us from harmful UV rays or radiation. But the closer ozone gets to the ground, the worse it is for us. Why? Because when various particles in the air react with ozone, smog is produced - yes, it's that grayish fog that we often see in heavily polluted industrial zones. This type of ozone is also called ground-level ozone.

It is probably no surprise to anyone that smog is extremely harmful both to us and to our environment. Smog is a very big irritant to our lungs and eyes, which further aggravates all respiratory problems such as allergies and asthma. Long-term exposure to smog can also lead to premature death. Some of the latest ozone studies show that ozone causes damage to our bodies long after we are no longer exposed to it (even if we feel fine).

The other two, slightly less widespread (but just as dangerous), types of air pollutants are:

• Sulfur dioxide. The source of sulfur dioxide is coal-fired power plants and non-ferrous ore smelters.
• Carbon monoxide. The main source of carbon monoxide is the burning of carbon fuels.

Diseases caused by polluted air

So far we have found that there are quite a few different types and sources of polluted air. There remains, of course, another very important question, namely how exactly polluted air can harm us or what diseases it can cause us.

To begin with, let's look at some recent statistics from the WHO (World Health Organization) on this topic. They found that global air pollution is to blame for:

• 29% of all deaths and illnesses related to lung cancer,
• 17% of all deaths and illnesses due to acute lower respiratory tract infection,
• 24% of all stroke deaths,
• 25% of all deaths are due to ischemic heart disease,
• 43% of all deaths and diseases related to chronic obstructive pulmonary disease (COPD).

The pollutants that threaten our health the most are the four main groups listed in the previous chapter - PM particles, ozone, sulfur dioxide and carbon monoxide.

However, not all groups of people are equally exposed to air pollution diseases. The elderly, children and people with pre-existing respiratory problems are the most affected. The latter are particularly exposed to ground-level ozone, as it greatly worsens the existing situation. There is also a growing body of new evidence that suggests that air pollution also affects diabetes and neurological development in children.

Vir: nijz.si

I would also stop for a moment on PM particles. These are those solid or liquid particles (in the beginning we mentioned them as aerosols) suspended in the air. Namely, we know three main groups of PM particles - PM10, PM2.5 and PM1 particles. The difference between them is only in size (particle diameter). PM10 are up to 10 micrometers in diameter. PM2.5 particles have a diameter of up to 2.5 micrometers and PM1 particles have a diameter of up to 1 micrometer.

The bottom line is this: the smaller these harmful particles are, the more dangerous they are to health. As a result, PM1 particles are among the most dangerous. Why? The finer the particles, the more difficult they are to disperse and therefore can more easily penetrate deeper into our bloodstream, where they cause even more damage. PM10 particles (ie the largest) can enter and stay in our respiratory tract, PM2.5 can reach even deeper into the respiratory tract due to their smaller size. Finally, we have PM1 particles (that's a lot of viruses and bacteria), which even penetrate into the cardiovascular flow, where they can cause cardiovascular diseases.

Measures to reduce air pollution (indoors)

In Slovenia, we have relatively less polluted air than in some other areas of the world - nevertheless, it is never superfluous to take extra care of your health. Reducing the amount of polluted air is one of those things that we have a lot of influence on individually.

The main air pollution problem for humans (perhaps surprisingly) is indoor air pollution. In addition to the previously mentioned sources of pollution, additional complications arise here due to two additional factors, namely;

•  Inadequate ventilation - if we don't have a sufficient supply of fresh air from outside, there can be a problem of more difficult dilution of emissions from internal sources of pollution.
• Room temperature and humidity - high temperature and humidity increase the concentration of certain types of pollutants.

The US Environmental Protection Agency (EPA) recently researched that indoor air pollution is 2x - 5x higher than outdoor pollution. This is quite a scary figure when we consider how much time (on average) we actually spend behind the four walls of our home!

So, what can we do on an individual level to reduce indoor air pollution? Here are some simple steps:

1. Frequent opening of windows: good ventilation or Air flow is the key to improving indoor air quality. Try to open the window as often as possible (when it is not too cold or when the concentration of pollen in the air is not too high).
2. Limitation of smoking - ideally, of course, smoking should be completely stopped behind the four walls, and this activity should be moved entirely to at least the balcony. But if this is not possible, try to smoke as little as possible at home. Cigarette smoke, in addition to a strong and lasting smell, is also a problem due to the so-called "passive smoking".
3. Think of a doormat if you don't happen to have one yet. It may sound funny at first, but wiping your shoes on the carpet greatly reduces the number of pollutants introduced into our homes.
4. More frequent cleaning with a vacuum cleaner - this is especially important if you have a furry friend at home.
5. Using a microfiber cloth instead of a regular cloth - a microfiber cloth will capture much more dust (PM10 particles) than a regular, cotton cloth.
6. More plants in the room! – plants are a very healthy (and also cheaper alternative) to air purifiers. Although they have a limited ability to purify the air, they still remove a wide range of chemical compounds from the air.
7. Consider investing in more environmentally friendly cleaners - many of the cleaners that most of us use on a daily basis contain many harmful chemicals that linger in the air. The main problem here is formaldehyde and volatile organic compounds, which are very harmful to our body (if we inhale them).
8. Consider an air purifier - Air purifiers are currently the best way to drastically reduce airborne pollutants. Nevertheless, you have to be careful here, because there are many types of air purifiers on the market, not all of which are suitable for every situation. Currently, 2 types of air purifiers are most popular: HEPA filters and ionizers. If you are interested in the difference between HEPA filters and ionizers in more detail, you can read a separate entry on this topic on our blog - you can find the link if you click here.

These are just some of the main measures you can take today to drastically improve the air quality at home. At the end of the day, these measures do not require a lot of work and time, but they offer a very large contribution. In any case, prevention is better than cure in this case.

stay healthy,

IONEX team