- Dhaka's air is thick with dust, worsened by no rain
- Poor air quality is causing health issues early this winter
- November to February are the most polluted months
Dhaka's air is thick with dust, particularly noticeable over the past few days due to the lack of rain in November.
The hazy layer of dust in the atmosphere is visible even when looking at the open sky.
According to the Center for Atmospheric Pollution Studies (CAPS), air quality from November to February has been the most hazardous over the past nine years.
On November 16, Dhaka’s Air Quality Index (AQI) score spiked to 269 – the highest this year so far, CAPS says.
This poor air quality has led to health complications even before the full onset of winter.
Data analysis:
Dhaka’s AQI score stood at 160 at 11:30am on Wednesday, ranking it eighth among the world’s most polluted cities.
It was much worse at one point in the previous morning, at 234, making it the fourth most polluted city.
The Air Quality Index categorizes air quality into six levels: 0–50: good; 51–100: moderate; 101–150: unhealthy for sensitive groups; 151–200: unhealthy; 201–300: very unhealthy; and above 300: hazardous.
A nine-year analysis reveals that January consistently experiences the most hazardous air quality in Bangladesh. However, the months from November to February are marked by particularly unhealthy air, making them the most polluted period of the year.
Data from the United States embassy in Dhaka over the past nine years indicates the following average AQI levels: 250 in January, 177 in November, 218 in December, and 221 in February.
Notably, January 2023 recorded the worst monthly AQI score average in 106 months, at 281.
In comparison, the least polluted month over this period was July 2021, with an average AQI score of 76.
Besides, the annual AQI averages were 159 in 2021, 160 in 2022, and 171 in 2023.
Contributing factors:
The lack of November rain has worsened air quality by increasing dryness and reducing the ability of trees to trap dust as they shed their leaves.
Additionally, winter marks the onset of the construction season in Dhaka, further elevating dust and pollution levels.
Dr. Ahmad Kamruzzaman Majumder, the founder of CAPS, highlighted Roadwork and infrastructure repairs, large-scale construction projects, brick kilns, industrial emissions, exhaust from unfit vehicles, and open burning of waste as the key contributors to the city’s air pollution.
He stressed the need for effective pollution control measures, warning that without immediate action, air quality in December could deteriorate further.
Health impacts:
Meanwhile, allergies become most severe during winter; people who suffer from dust and cold allergies usually experience the greatest discomfort during this season.
In Dhaka, the combination of cold weather and increased dust particles in the air exacerbates the situation.
Since the COVID-19 pandemic, the habit of wearing masks has increased globally, including in Dhaka, and doctors are again recommending the use of masks with the onset of the air pollution season.
Medicine specialist Dr MH Choudhury Lelin told this correspondent that air pollution caused three types of harm: immediate, medium-term, and long-term.
He said immediate effects included exacerbation of respiratory illnesses such as sneezing, coughing, and asthma.
“Allergies intensify, fungal infections increase, lung inflammation worsens, and diseases like pneumonia and tuberculosis become more common.”
Lelin added that medium-term effects involved the progressive deterioration of lung capacity. The fine particles responsible for air pollution reduced the elasticity of the lungs and could enter the bloodstream, impairing the liver and kidneys, he said.
“The primary long-term concern is lung cancer. Therefore, awareness and caution are crucial in this regard. Among other major risks, pregnant women face an increased chance of miscarriage, and there is also evidence of lower birth weights in infants.”
