Dhaka Hits Top of IQAir's Ranking As Most Polluted City

Amid the winter, the 'very unhealthy' air of Bangladesh's capital Dhaka registered as the worst in the world on Saturday morning. Five cities around the world register exceptionally high levels of air pollution, according to the observations of international air technology company IQAir.

Dhaka's air went from 'unhealthy' to 'very unhealthy' at 10 am on Saturday. Over the next two hours, Dhaka climbed to the top of the rankings, followed closely by India's Kolkata and Delhi. At 10 am, Dhaka's air quality registered at 279. It worsened to 281 at 11 pm and averaged at around 276 around noon.

The capital's Purbachal area recorded the worst air quality on Saturday, fluctuating between 'very unhealthy' (201-300) and hazardous (301+). An area's air quality index, or AQI, is measured by the amount of fine particulate matter (PM-10) and ultrafine particulate matter (PM 2.5) suspended in the air. The air quality assessment assigns scores to different cities worldwide based on how many micrograms of PM 2.5 are present per cubic metre of air.

The higher the AQI, the more dangerous the air is for humans. IQAir says 0-50 is 'good', 51-100 is 'moderate', 101-150 is 'unhealthy for sensitive groups', 151-200 is 'unhealthy', 201-300 is 'very unhealthy' and over 301 is 'hazardous'. Cities in the US, Japan, Canada and Australia registered the best air quality on Saturday.

Dhaka regularly ranks among the cities with the worst air quality in the world. The air pollution is nasty in winter, posing a danger to public health. Experts blame pollution for the uptick in hospital patients around this time.

The pollution is also affecting the severity of the winter, they say. They recommend taking precautions such as wearing masks to reduce the effect. Dhaka's air quality has registered as 'very unhealthy' for 21 days in January. Last Friday, it reached the 'hazardous' level of 317.