The world’s 100 most polluted cities are all in Asia. In November 2024, air pollution in India’s largest cities, such as New Delhi and in areas of Pakistan was very intense, with the result that local authorities urged residents to stay in their homes.

However, air pollution is… omnipresent and we are exposed to it whether we are walking the streets of a city full of factories or we are stuck in a traffic jam or again we are in a rural area, where the residents light a fire in the fireplace to keep warm.

So for many people in the most polluted areas it is difficult to avoid polluted air.

Why is the “cloud” dangerous?

“Photochemical smog,” as the smog that forms over big cities due to air pollution is called, occurs when toxic chemicals at ground level interact with solar radiation. And it’s particularly dangerous because people can’t help but inhale it.

Combustion processes – from a factory, a car engine or anywhere else – release toxic gases into the atmosphere. In this way, microscopic particles are dispersed in the atmosphere, which end up in our lungs, are absorbed by our blood and can cause us serious health problems in the long term.

Short-term exposure can worsen existing conditions, such as asthma and other respiratory problems and infections, by damaging lung function. Long-term exposure can, on the other hand, cause chronic diseases, from cancer to strokes and heart attacks.

In fact, exposure to air pollution is dangerous for all adults regardless of age – although children and the over 65s are even more at risk.

A study last May of lower-emission areas in Germany found that children who breathed clean air from conception to one year of age were less likely to need medical care in their first five years of life.

“Exposure to air pollution at such a young age can have long-term effects on children’s lives,” says researcher Hannah Klauber.

Previous research has also shown that children who are more exposed early in life tend to perform worse in school, do less well in competitions and overall even end up with lower earnings as adults.

“We have found in many studies that there is no safe level of air pollutants,” Klauber tells DW. “So any increase in particulate matter leads to serious implications for human health.”

Air quality in an area is measured through a special assessment process, which often shows some differences from country to country, as the criteria are usually set by national governments. Of course, there are several countries that simply follow the criteria set by the World Health Organization.

Can we protect ourselves from the cloud?

Those in areas with intense photochemical smog cannot do much to completely protect themselves from its effects.

In some cities with heavy air pollution, such as New Delhi, it is the local authorities themselves who often place restrictions on citizens’ activities – for example by closing schools, limiting the number of vehicles allowed to circulate or banning outdoor work – or simply urge citizens to avoid exposure to pollution as much as possible.

However, according to Rajib Dasgupta, professor of public health at Jawaharlal Nehru University in New Delhi, such restrictions are only temporary solutions.

“It is not a problem to be dealt with by personal interventions or restrictions on citizens. Large-scale state-initiated actions are needed, which will include many sectors of society,” the professor tells DW.

Globally, some such efforts are indeed being made at the level of governments. The EU agreed in June on new standards regarding air pollution, while similar efforts are underway in Asia, especially in the areas facing the biggest problems, such as Beijing.

In 2013, Beijing authorities came up with a plan to make the city’s public transportation electric. In this way, the smog and pollution in the city was significantly reduced. However, pollution levels still exceed government and global air quality standards. India has also taken similar measures.

However, Dasgubta openly criticizes governments, arguing that no significant progress has been made: “States do not seem to be able to act. And this is not due to a lack of money, but to the absence of will.”

Edited by: Giorgos Passas