Air pollution in Dhaka city is five times higher than the tolerable level, according to a study of the Center for Atmospheric Pollution Studies (CAPS) at Stamford University.
The level of air pollution varies at different places. Farmgate area in Dhaka was the most polluted for four years, but Lalbagh of Old Dhaka took the position this year.
Farmgate is now in second position while air pollution at English Road of Old Dhaka, Segunbagicha, Shankar of Dhanmondi, Naya Paltan and Hazaribagh is on the top.
CAPS monitors air at 70 places in the capital between November and December.
The environment department fixed 70 places to monitor sound and air pollution.
Air monitoring devices of four organisations were used to assess the quality of air.
The quality of air is mainly determined by assessing Particulate Matter PM-1, PM-2 and PM-10 in the air.
The study has been done based on the level of air pollution determined by World Health Organisation (WHO).
Speaking to Prothom Alo, CAPS director professor Mohammad Kamruzzaman Majumder said, “Black smoke emissions from the huge number of old and unfit vehicles in the capital, smoke from the factories and polluted air moving in from across the border have polluted air in the capital city.”
“Earlier, we considered that brick kilns were the sources of 60 to 65 per cent air pollution in Dhaka,” he added.
The environment department so far has maintained that brick kilns are the main source of air pollution in Dhaka.
Other sources are dust, smoke emitted from vehicles and factories.
According to CAPS study, the amount of PM-2.5 is higher in the air of Dhaka. This comes from fossil fuel, that is, from smoke emitted from factories and vehicles.
Speaking to Prothom Alo, Dhaka University professor and air pollution researcher Abdus Salam said brick kilns remain operational for 100 days between November and March. But air in Dhaka city remains unhealthy for 300 days. So other sources including smoke from vehicles play a major role in polluting air in the capital.
The study of CAPS divides Dhaka city into four in categories of population and land use.
First, there are the sensitive areas where there are educational institutions, offices and hospitals. Particulate Matters (PM) in 20 Dhaka areas have been found more than four and half times higher what it should be.
Jagannath University is the most polluted area. The amount of Particulate Matter (PM-2.5) in the air is 366 micrograms per cubic meter. The amount is 366 micrograms in Dhanmondi Boys School and 350 in the secretariat respectively. The quality of air is comparatively better in Shahbagh and Uttara area.
More than four and half times higher PM has been found in the air of 20 residential areas.
The air in the Srinath Street of Lalabagh in Old Dhaka is mostly polluted. PM in the air have been found a total of 507 micrograms.
The air of Manipuripara of Farmgate and Dholpur of Jatrabari is the next most polluted.
The quality of air is comparatively good in Manikdi of Dhaka Cantonment and Gulshan area.
A total of 449 micrograms in the air have been found in the commercial Ulan area of Rampura. Then Islampur of Old Dhaka and Paltan are mostly polluted. The air is comparatively good in Banglamotor and Jasimuddin Road of Uttara.
PM exists 4.7 times higher than the normal level in 15 commercial areas.
Out of 20 mixed areas, PM (369 micrograms per cubic meter) in the air is found in front of police box at Farmgate. Bangsal and Naya Paltan come next.
The quality of air has been found better comparatively in New Market and Boro Maghbazar area.
PM is found more than five times higher in five industrial zones. The worst condition has been found in Dolaipar of Jatrabar, with 436 micrograms.
Director general of the environment department AKM Rafiq Ahmed said, “We have discussed with experts about the source of air pollution in Dhaka and its remedy.”
Experts have also priortised other sources than the brick kilns for air pollution in the capital, he said adding air pollution has not been reduced despite shutting down brick kilns.
Besides, thousands of trucks and long route vehicles enter Dhaka city from outside every night. These vehicles bring in huge amounts of sand and soil on their wheels. This contribute to the air pollution.
Rafique Ahmed said they are working on the control of these sources of air pollution.
Dhaka ranked the 2nd worst again in Air Quality Index (AQI) on Sunday.
The independent live air-quality index monitor, Air Visual, shows Dhaka’s AQI value as 241 around 9:30am.
Mongolia's Ulaanbaatar topped the list with an AQI score of 305 while Vietnam’s Hanoi and Pakistan's Lahore stood third and fourth in the list of poor air cities with AQI values 232 and 218 respectively.
Earlier, on 17 and 23 November, 26 December and 6, 29, 31 January and 9, 14, 18 and 19 February, Dhaka had topped the list. The city has been continuously among the five most polluted cities around the world.
*This report, originally published in Prothom Alo print edition, has been rewritten in English by Rabiul Islam.