Data from the World Health Organization has given information on the cities with the worst air pollution in the world.
These findings are based on levels of fine particulate matter (PM2.5) in the atmosphere of these cities. PM2.5 can affect the health of people who inhale them. It can cause irritations in the respiratory tract, but it can also cause worse respiratory and cardiovascular diseases.
The cities on this list have the highest levels of fine particulate matter in their air. They far exceed the PM2.5 levels recommended by the WHO, which is 18 micrograms per cubic meter compared with 10 micrograms per cubic meter (µg/m³).
Al Jubail has 152µg/m³ of PM2.5 in its atmosphere, which ranks the city fifth among the cities with the worst air pollution.
Riyadh's air has 156gµg/m³ of PM2.5. Riyadh is Saudi Arabia's capital, with a population of 6,506,700 as of 2016.
Allahabad has 170gµg/m³of PM2.5. It is the most populated city in the state of Uttar Pradesh. Delhi, another Indian city, used to have the worst air pollution in the world, but it now has a relatively low level of PM2.5 at 122gµg/m³.
Gwalior is another densely-populated Indian city. It has 176gµg/m³ of fine particular matter in its atmosphere.
Zabol has 217µg/m³ of PM2.5 in its atmosphere. It thus takes first place among the cities with the worst air pollution.
Air pollution is almost like a fact of life when living in urban areas. Most people who live in cities have to live with air quality that far exceeds the WHO's air pollution limits. These limits determine whether air quality is safe or not. Exceeding these limits means that the air in certain areas can negatively impact the residents' health.
According to the WHO's data, nearly all cities in low-income and middle-income countries exceed safe PM2.5 levels. Cities are usually host to a lot of people because of education or job opportunities. This means that a lot of people are at risk of developing respiratory and cardiovascular conditions.
This data is just about the presence of PM2.5. The findings may be different if we look at other pollutants such as ozone or airborne ammonia. Beijing and Los Angeles have high recorded levels of ozone. Karachi actually holds the title for worst ozone pollution. Delhi, meanwhile, may not have the worst air pollution anymore, but it does still have high levels of ammonia in its air.
Though we can expect to live with bad air pollution when we live in cities, it doesn't mean that it's acceptable. These cities with the worst air pollution in the world have large populations, which means that a lot of people are literally breathing in something that can cause them harm. In the interest of public health, governments around the world need to put more work into improving the air quality in their urban areas.
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