An article by Ludovica Iaccino, International Business Times UK.

To celebrate the World Environment Day on 5 June, a day designated by the UN to raise awareness of environmental issues, IBTimes UK looks at some of the countries with the highest rates of pollution.

According to World Health Organisation (WHO) air pollution – both indoor and outdoor – is the leading cause of death worldwide.

The main causes of pollution are: uncontrolled emissions from motor vehicles, dust, industrial waste, garbage, brick kilns, cooking stoves, burning of wood, coal and bio-mass.

WHO examined the concentration of fine particulates – tiny pieces of solid or liquid matter suspended in the atmosphere – of 2.5 micrometres or less in diameter (PM2.5).

These particulates are small enough  to pass into the bloodstream and cause diseases such as emphysema and cancer.

PM 2.5 is the best indicator of assessing health impacts from air pollution.

The concentration of air pollution is measured in micrograms per cubic metre of air (ug/m3).

India

The levels of air pollution in Delhi were measured at 163 ug/m3 – the worst air conditions in the world.

This concentration of air pollution is far greater than what is usually considered safe.

“Too many urban [centres] today are so enveloped in dirty air that their skylines are invisible,” Flavia Bustreo, WHO Assistant Director-General for Family, Children and Women’s Health, said.

Half of the top 20 cities in the world with the highest levels of PM2.5 are in India, according to WHO.

Bangladesh

The Bangladeshi city with the highest air pollution rate was Narayonganj with a rate of 89 ug/m3, followed by Gazipur (87 ug/m3) and Dhaka (86 ug/m3).

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