Can Dhaka improve its air quality?

Many of those who live in Dhaka these days say that they will look at other cities to move out if there is any opportunity as they find the capital city unlivable due to its worsening air pollution.

"Living in Dhaka has become a personal battle because its air has become too unhealthy for living," says Mujibul Haque, a retired engineer.   

The residents of Dhaka breathed with the worst and unsafe air from January to March this year as they did during the same period in 2017.

During this 90-day period (January-March 2021), the air quality was recorded as 'hazardous' for 12 days, 'very unhealthy' for 58 days, 'unhealthy' for 19 days and 'unhealthy for sensitive groups' for one day in Dhaka, one of the most polluted cities in the world.

This awful scenario was found after the analysis of the Air Quality Index (AQI) data of the first three months of 2017-2021.

In 2021, the average daily AQI score was 261 in January, 231 in February and 211 in March, which hit the record high in the last five years.

The average AQI scores were 247, 193 and 170 in January-March 2017 respectively, according to the analysis made by Prof Dr Ahmad Kamruzzaman Majumder, Founder and Director of Centre for Atmospheric Pollution Studies (CAPS) run by Stamford University Bangladesh.

During the five years, the air quality was relatively better in 2020 as the average AQI scores were 235 in January, 220 in February and 175 in March in the year.

Besides, the average AQI scores were 240, 226 and 191 in the first three months of 2019, while 256, 224 and 183 in January-March of 2018.

In January 2021, the air quality in Dhaka was hazardous (score 300+) for seven days, while very unhealthy (score 200-300) for 23 days and unhealthy (151-200) for one day.

Dhaka's air quality was hazardous for three days, very unhealthy for 20 days and unhealthy during the remaining five days in February.

In March last, the air quality was hazardous for two days, very unhealthy for 15 days and unhealthy for 13 days and unhealthy for sensitive groups (score 101-150) for one day.

In the last three months, the highest average AQI score was 365 on January 20 and the lowest 144 on March 11, 2021.

Although the hazardous air quality poses serious health risks to residents, little is being done to keep people safe and check the air pollution. 

People are advised to avoid all outdoor exertion when the air quality is hazardous, said Dr Majumder, also chairman of the Department of Environmental Science of Stamford University. 

Dhaka that has long been grappling with poor air quality is frequently ranked the most polluted city or the second or third most polluted city in the world.

Covid-19 and poor air quality

Amid the Covid-19 pandemic, the poor air quality has emerged a matter of grave concern for the city dwellers as there is a correlation between severity of coronavirus virus infection and long-term exposure to air pollutants.

Air pollution consistently ranks among the top risk factors for death and disability worldwide.

With the deterioration in the coronavirus situation, the country's air quality now can pose a big challenge to the authorities concerned for saving the lives of people.

Experts say the exposure to a high level of air pollution weakens people's respiratory and immune systems, causes various cold-related diseases, making them more susceptible to Covid-19.

The World Health Organization (WHO) has also recently cautioned that the cities which have a higher level of air pollution should reinforce their preparedness against the deadly corona pandemic.

Experts also say the use of masks by all must be ensured by enforcing law and motivating people as it is the most effective way to protect oneself from pollution and Covid-19.

Air pollution and Diseases

Breathing polluted air has long been recognised that it increases one's chances of developing heart diseases, chronic respiratory diseases, lung infections and cancer, according to several studies.

As per the World Health Organization (WHO), air pollution kills an estimated seven million people worldwide every year, largely as a result of increased mortality from stroke, heart disease, chronic obstructive pulmonary disease, lung cancer and acute respiratory infections.

Generally, Dhaka's air starts getting fresh when monsoon rain begins from mid-June and the air remains mostly acceptable from June to October.

A report by the Department of Environment (DoE) and the World Bank in March 2019 pointed out that the three main sources of air pollution in Dhaka are brick kilns, fumes from vehicles and dust from construction sites.