Particulate Matter (PM)

Particular Matter, also called particulates, are simply the sum of all solid and liquid particles suspended in the air. Many of these particulates are hazardous and only a part of them can be seen with the naked eye.  If we talk about inhalable particles we have usually a look at 3 different particle sizes:

PM1            smaller than 1 µm (dust, combustion particles, bacteria and viruses)
PM2.5        smaller than 2.5 µm (pollen, spores and other organic particles)
PM10         smaller than 10 µm (coarser fine dust and organic particles.

What we need to understand is the smaller the particle, the more harmful it is for our health. Our lungs are particularly vulnerable to PM1 as the inhaled particles travel to the deepest area of the lungs and a significant proportion of them pass through the cell membranes of the alveoli (the tiny sacks meant to exchange O2 and CO2) and enter the blood stream. This contributes to deadly diseases like heart attacks, lung cancer, dementia, emphysema, oedema and other serious diseases.


All of us have to be aware of the particulate pollution in the air and here it needs to be stressed that that includes the indoor pollution and not just outdoors!

According to the Environmental Protection Agency, the average American spends 93% of their life indoors, and it is pretty safe to say that this figure can be applied to pretty much all of the more economically developed countries (MEDC).

Many super fine particulates are produced by indoor activities like cooking, smoking or a caused by mold, pets or mites. The latest surveys show that the rates of allergy are increasing throughout the world, affecting up to 30-35% of people at some stage in their lives.

This increase was initially seen in countries such as the UK, Europe and USA, but can now be found in all countries undergoing industrial development. The pattern of allergy is also changing – initially, the increase was in asthma and allergic rhinitis (hay fever). However, recent studies have confirmed a significant increase in the incidence of food allergies, in particular among the children. In the UK, it is estimated that up to 50 per cent of children are diagnosed with an allergic condition.

Outdoors this particulates manifests in that what we call smog. Human-made smog is derived from coal, vehicular and industrial emissions, as well as from forest and agricultural fires and photo-chemical reactions of these emissions and are composed mainly of nitrogen oxides, sulfur oxides, ozone, smoke or particulates among others (less visible pollutants include carbon monoxide, CFCs and radioactive sources).

The World Health Organization (WHO) till today did not published any guideline values for particulate matter. Nevertheless most countries around the world have standards in place or work on setting up standards in acknowledgement of the constant growing negative effect on health and to protect the most sensitive groups of people, including infants, children and elderly persons with heart or lung diseases. To learn about the standards please refer to the section standards.

More and more countries restrict the type of vehicles what are allowed to enter a city area or pass through it.

That at least will help certain areas, but…..does it help you?

Source of air born particulate matter

Some particulates occur naturally, originating from volcanoes, dust storms, forest and grassland fires, living vegetation, and sea spray. But human activities, such as the burning of fossil fuels in vehicles, power plants and various industrial processes, and incinerating wastes generate the majority amount of particulates.

The source and the composition of particulates pollution is not the same around the world. When examining the individual sources of air pollution. “It is generally assumed that industry and transport are the worst air polluters. But that is evidently not the case on a global scale,” says Lelieveld. Much of the smog in India and China is caused by small domestic fires. “Although these are low-key activities, they add up, particularly if the majority of the population uses them,” he says. Overall, one-third of premature deaths worldwide are attributable to this inefficient form of combustion.

In 2015, it was detected that Indonesia cumulated more than 120,000 forest fires and in October more than 20,000 fire fighters were battling blazes across the country. Such an enormous amount of carbon emitted in the atmosphere does not have only made Indonesia suffer but effected the whole Asian region. In the worst hit areas of Sumatra and Kalimantan the levels of the Pollutant Standard Index (PSI) have pushed toward 2,000 – anything above 300 is considered hazardous.

By contrast, a leading cause of air pollution in Europe, Russia, Turkey, Japan and the eastern United States is, surprisingly, agriculture. Ammonia enters the atmosphere as a result of the use of fertilizers and intensive livestock farming. It then undergoes a number of reactions to form ammonium sulphate and ammonium nitrate. These substances, in turn, are a major factor in the formation of small airborne particles. In fact, agriculture is the cause of one-fifth of all deaths due to air pollution. In some countries, for example in the Ukraine, Russia and Germany, this figure is over 40 percent.

Other major sources are fossil-fuel fired power plants, industry, biomass combustion and motor vehicles. Taken together, they account for another third of premature deaths. Just under a fifth of premature deaths are attributed to natural dust sources, particularly desert dust in North Africa and the Middle East.

Keep in mind that around twice as many people die from the effects of vehicle emissions than from road accidents!