In pictures: Riyadh and Cairo are among the most polluted cities in the world

ArabiaWeather.com- There has been much talk recently about the air problem, which is defined as the exposure of the atmosphere to chemicals, physical particles, or biological compounds that cause harm and harm to humans and other living organisms, or lead to damage to the natural environment, which poses a threat to human life and ecosystems existing on planet Earth.

These pollutants may be in the form of solid particles, liquid droplets, or gases, in addition to that they may be natural or resulting from human activity, with a rate of 40% in the Arab world.

Recently, the German Broadcasting Corporation "Deutsche Welle" published a report on the countries that suffer the most from air pollution, explaining its causes and effects, quoting the World Health Organization, and both Riyadh and Cairo came among the most air-polluted cities in the world. The most polluted cities around the world:

The city of Ahwaz (the capital and center of Khuzestan Province) in Iran topped the list of cities most affected by air pollution in the world, due to the size of heavy industries in the city, which depend on oil, minerals and natural gas in the production process.

In second place came the city of Ulaanbaatar in Mongolia, as one of the cities that suffers most from the problem of air pollution, as fireplaces lit by citizens using coal and wood contribute to 70% of the air pollution in the city.

The Pakistani city of Lahore , and air pollution is one of the most important problems of the state of Pakistan in general, especially in "Lahore", its second largest city, due to the continuous burning of garbage and dust emanating from the surrounding desert environment, in addition to the high traffic density.

New Delhi - the capital of India, and the reason for air pollution there is the high traffic density, as the number of cars increased from 180,000 to more than 3.5 million in the last three decades, as well as the proliferation of coal-fired factories, which is the main reason behind air pollution there. As these factories contribute 80% of the causes of this pollution in the city.

The city of Riyadh, where most of the causes of air pollution are attributed to sand storms, in addition to pollutants resulting from transportation and industrial waste.

Cairo, where the high rate of air pollution is due to the huge traffic density and the prosperity of the industrial sector, which results in air pollution that causes high rates of respiratory diseases and chronic lung diseases.

The city of Dhaka - Bangladesh. Studies indicate that 15,000 people die annually due to air pollution there, as researchers have found that it contains the highest concentration of toxic "sulfur dioxide" gas there.

Moscow - the Russian capital, and the air molecules in Russia are characterized by a high percentage of hydrocarbons (fuels), while the western part of the city enjoys a better weather nature, thanks to the western winds that blow over the region regularly.

Mexico City - In Mexico, the increase in air pollution rates is due to its geographical location, as it is surrounded by mountain ranges from three directions, and it is considered one of the cities most affected by air pollution around the world due to the high proportion of "sulfur dioxide" gas and hydrocarbons.

Although Beijing , the capital of China, is one of the countries in the world that suffers the most from air pollution to the extent that citizens are constantly forced to wear protective masks while they are outside, the World Health Organization did not classify it among the 10 cities most suffering from the problem of air pollution around the world, as The most affected cities were among the smaller cities in terms of area and population density, especially in developing countries.