All because of the ozone in the air of cities.
The concentration of ozone, which is the main component of urban smog, which directly affects the level of mortality in large cities. This is stated in the conclusions to a large-scale study of the relationship between air pollution and premature deaths of the inhabitants of the cities, reports the Chronicle.info with reference to League.no.
A strong oxidizer, ozone in many reactions, breaks down into toxic free radicals of oxygen. The concentration of this gas in large cities will grow in Sunny and calm weather due to the acceleration of photochemical reactions with substances-pollutants.
Taking data for 406 cities in 20 countries over the years 1985-2015 (analyzed over 45 million deaths), the researchers searched for a correlation between the number of deaths per day and the ozone levels, the number of particulates in the air, its temperature and humidity.
It was found that approximately 80% of citizens in the world are constantly influenced about threshold levels of ozone, and the increase of its concentration to 0.01 mg/m3 even for one or two days will increase the risk of premature death by 18%.
HELP. Ozone — a molecule consisting of three oxygen atoms. Blue poisonous gas with a pungent characteristic odor, perceptible even when diluted 1:100000. Highly toxic, a proven risk of its mutagenic and carcinogenic effect. Ozone is responsible for screening deadly ultraviolet radiation from the Sun. The greatest concentrations in the atmosphere at a height of from 18 to 35 km above sea level. The maximum allowable ozone concentration in the surface air at the standard who — 0.10 mg/m3 EU — 0,12, USA — 0,14, China — 0,16.