Air too polluted for 9 out of 10

It is a portrait of a world that suffocates, one delivered by the last World Health Organization report on air pollution, published yesterday, 92% of the world's population, more than 9 out of 10 people, breathing polluted air, in where the most dangerous fine dust - those with a diameter less than 2.5 microns - exceed the standard safety levels.

The data were collected in more than 3,000 cities in the world, both with satellite technology is, where possible, with measurements at ground level (not always available in the poorest countries). Are the most accurate information ever on the health of our atmosphere.

LIMITS SFORATI. A yearly average concentration of PM 2.5 greater than 10 micrograms per cubic meter is considered to be sub-standard and dangerous to health. Over six million deaths a year worldwide are attributable to the effects of pollution on the outside and inside buildings.

THE POVERTY FACTOR. More than 90% of these deaths occur in low and middle income countries from where the problem of the external pollution is added to coal-fired cookers, stoves and other unhealthy systems for heating and cooking. The regions of Southeast Asia and the Western Pacific (including China, Malaysia and Vietnam) report the most alarming data.

MYTHS debunked. Particulate matter 2.5 is a powder that can penetrate deep into the lungs and cardiovascular system. Recent studies have found magnetic tracks due to smog even in the brain. Stay indoors in intense smog days does not seem to greatly improve the health effects: to do damage is indeed prolonged exposure to particulate matter.

There is no evidence that masks prevent inhalation, and rural areas do not seem immune from the phenomenon: the pollution is worse in the cities but in the countryside the situation is not as rosy as it seems.

BULLETS IN THE VACUUM. In short, there is enough to cause concern, concludes the WHO. Which calls on governments to take urgent and drastic measures to reduce road traffic, encourage cooking methods that are cleaner and better management of municipal waste.