Bangladesh 4th most polluted in world
Bangladesh has been ranked fourth among 91 countries with worst urban air quality in the latest air pollution monitoring report of World Health Organisation (WHO).
Moreover, three Bangladeshi cities have been put among the top 25 cities with poorest air.
The 2014 version of the Ambient Air Pollution (AAP) database consists mainly of urban air quality data of 1600 cities from 91 countries.
Pakistan has been shown as the worst country in the category with Qatar and Afghanistan ranked second and third. Iran, Egypt, Mongolia, United Arab Emirates, India and Bahrain take the other spots in the worst ten.
In the city-wise assessment, Narayanganj has been marked as the 17th city with worst air quality whereas Gazipur and Dhaka have been ranked 21st and 23rd respectively.
In the report, six of the top 10 cities with highest air pollution were from neighbouring India with Delhi taking the first spot.
The other Indian cities in the top chart are Patna in the second spot, Gwalior third, Raipur fourth, Ahmedabad ninth and Lucknow tenth. Pakistan's Karachi has taken the fifth position.
The report says that almost 90 percent of people living in the cities are being exposed to dangerous levels of air pollution.
Outdoor air pollution killed 3.7 million people in 2012 and the WHO says it is now the world's largest single environmental health risk.
The report also states only 12 percent of people are living in cities that conform to the WHO air quality guideline levels.
The report was more extensive than a similar database released by the WHO in 2011.
The report was prepared on the basis of the monthly air quality monitoring data of 2013 of the Department of Environment (DoE), Bangladesh.
The DoE has set up air quality monitoring stations in eight cities, including Dhaka, Narayanganj, Gazipur, Rajshahi, Chittagong, Khulna and Sylhet.
Though Narayanganj has the highest level of gaseous pollutants, the report shows the air of the northern metropolis Rajshahi contains the highest level of dust particles.
Among the gaseous pollutants which the DoE measures are carbon monoxide (CO), sulphur dioxide (SO2), oxides of nitrogen (NOx) and ozone (O3), methane and non-methane pollutants.