The World Health Organization has released its 2016 update to the Global Urban Ambient Air Pollution Database, revealing which regions in the world have dirtiest air.
The database covers over 3,000 cities across the world, measuring fine particle matter (both PM2.5 and PM10 microns) in micrograms per cubic meter (mg/m3).
PM2.5 measurements can directly be linked to estimates of health risks, the WHO said, as the particles are so fine they can travel deep into lungs and cause a variety of ailments.
The WHO’s Air Quality guideline recommends a PM10 maximum annual mean level of 20 mg/m.
According to the body’s latest update, more than 80% of people living in urban areas that monitor air pollution are exposed to air quality levels that exceed this limit.
The global health body said the aim of the database is not necessarily to rank cities or countries, but to rather reflect the monitoring efforts undertaken in those countries.
However, the findings give a clear indication of where the world’s worst air pollution problems persist.
By far and large, Indian cities dominate the top ranks in the database, with a large amount of urban areas and heavy industrialisation. Other countries which feature with high rates of air pollution include Saudi Arabia, China, Pakistan and Iran.
Iranian city, Zabol, was top-ranked, with a P2.5 rate of 217 mg/m3.
In terms of African cities, Kampala (Uganda) and Kaduna (Nigeria) were among the top 50 most polluted cities.
South Africa’s air pollution
In South Africa, the number of regions that track air pollution have increased and been added to the database.
In 2013, Joburg, being the most populated urban region in the country was unsurprisingly ranked as having the most polluted air.
However, in the 2016 update, a new addition has overtaken Joburg’s economic capital to claim the top spot: Hartebeespoort.
Haretbeespoort is not an obvious candidate for ‘worst air pollution in South Africa’, though the region’s air quality problems have been raised several times over the past decade.
The region’s air quality is adversely affected by its proximately to Tshwane and Johannesburg (both remain high on the list – with Tshwane now second in South Africa, ahead of Joburg), as well as mining operations in area.
Overall, it was ranked as the 162nd most air-polluted area in the world, with a PM2.5 rate of 60 mg/m3.
Mining operations are one of the biggest reasons for many smaller South African urban areas featuring in the database.
These are South Africa’s most air-polluted regions
|#||Urban area||Province||PM2.5 (mg/m3)|
|13||Cape Town||Western Cape||16|
Source: Business Tech