Global study reveals mixed success in tackling deadly air pollution

A group of researchers from the University of Leeds and other scientific centres worldwide have developed detailed charts that present PM2.5 concentrations in the capitals of all countries. The data for these studies come from computer simulations and satellite observations. Thanks to these methods, scientists could estimate how the concentration of particulate matter in the air has changed since the beginning of the industrial revolution. The data can be seen on a particular map available here.

The research results show that some successes have been achieved in improving air quality, but at the same time, they point to many challenges that still lie ahead of us. Dr Kirsty Pringle from the University of Edinburgh (United Kingdom) emphasises: "Air pollution is often called the 'invisible killer', but these images make the invisible visible, showing the changes in particulate matter pollution over the decades."

Professor Jim McQuaid from Leeds’ School of Earth and Environment adds: "The bottom line is that air pollution is one of the world's leading risk factors for death, it is thought to contribute to one in ten deaths globally. Our Air Quality Stripes show the huge range in trends and concentrations around the world. The stripes demonstrate that there is still more work to be done to reduce people’s exposure to poor air quality, and in some places a great deal more."

Scientists draw several key conclusions from their research. First, air quality in Europe, particularly in its western part, is improving due to legal regulations and technological progress. However, the situation is worsening in Central Asia and some African regions. Scientists believe that rapid urbanisation, industrialisation, and the lack of adequate legal regulations are to blame.

Researchers emphasise that there are enormous differences in air quality around the world. In some places, pollution comes from other sources, such as forest fires or desert dust, in addition to human activities.

The World Health Organisation (WHO) recommends that the average annual PM2.5 concentration not exceed five micrograms per cubic metre. This would indicate excellent air quality; however, it is essential to remember that medicine does not recognise a safe level of PM2.5. Unfortunately, at present, 99% of the world's population lives in places where the concentration exceeds the value indicated by WHO. The highest levels of PM2.5 are usually found in low and middle-income countries.

PM2.5 particles, which were the subject of this analysis, are hazardous because they can penetrate deeply into the body, reaching various tissues. They have even been found in the blood of newborns.

Long-term exposure to high concentrations of this particulate matter can lead to respiratory diseases such as asthma, chronic obstructive pulmonary disease, or lung cancer. It can also trigger and even worsen cardiovascular diseases, leading to heart attacks and strokes. Research also shows that PM2.5 can negatively affect foetal development and cause premature deaths. Consequently, limiting exposure to PM2.5 is crucial for protecting public health.