Weather change is also a major cause of asthma, chronic abstractive pulmonary disease and other breathing problems.
Eleven-year-old Isha Akhter and her father were waiting at the Asthma Centre of Dhaka Shishu Hospital. The fourth-grader has been suffering from cough and breathing problems for the last few days.
She uses a mask to avoid dust on her way to school, but still, her condition is not improving. So her father, Md Harun Islam, a resident of Mirpur, brought her to the hospital.
Experts said children are at greater health risks caused by air pollution in Dhaka.
Professor Abdus Salam of the Department of Chemistry at the University of Dhaka has been doing research on air pollution for 20 years.
Talking to The Business Standard, he said that the air quality in Dhaka has deteriorated due to the increase in dust and industrial smoke.
The absence of rain has also impacted the air quality, he said, adding that this is causing many diseases, including cancer, and children are at the greatest risk of health hazards.
The chemistry department examined air pollution levels at 10 educational institutions in the capital and found that the number of harmful particles in the air of classrooms and school compounds is four to five times higher than the standard set by the World Health Organisation.
Researchers examined 250 children aged between nine and ten and found that 16.8 percent were suffering from cough, six percent from asthma or breathing problems and 5.6 percent from migraine or headaches.
Besides, 55 percent of the children who previously had no history of breathing problems are not breathing normally now.
Doctors at the Asthma Centre of Dhaka Sishu Hospital told The Business Standard the number of child patients having asthma or breathing problems has increased in the hospital recently.
Adults suffering too
Adults are also facing difficulties and health hazards due to the falling air quality of Dhaka. In the last few days, the National Institute of Diseases of the Chest and Hospital, and Shaheed Suhrawardy Medical College and Hospital have seen an increasing number of patients with many problems, including breathing problems and asthma.
Dr Sadia Sultana at the National Institute of Diseases of the Chest and Hospital told The Business Standard that weather change is also a major cause of asthma, chronic abstractive pulmonary disease, and other breathing problems.
"We are mostly getting elderly patients," she said, adding that those who have a previous history of asthma and breathing problems are also coming to the hospital.
Brick kilns key source of pollution
According to the Air Quality Index (AQI), at 8am on Monday, Dhaka's score was 242, which is very unhealthy. For eight days in November, it was ranked as the city having the most polluted air.
According to a report from the State of Global Air 2019, 1.23 lakh people died in Bangladesh in 2017 due to air pollution.
Masks do not protect people from pollution if the AQI passes 200, doctors said. Such air quality can cause long-term headaches, severe breathing problems, kidney issues, cancer, and other major health hazards.
According to experts, air pollution is mainly caused by brick kilns and construction projects.
Dr Lelin Chowdhury, an expert on preventive medicine, said 56 percent of air pollution is caused by brick kilns.
He said brick kilns need to be controlled to improve the air quality.
"Fitness of vehicles needs to be monitored strictly and trees must be planted to improve the air quality of the city," added Dr Lelin.