Extreme air pollution in some cities in the country has been creating serious health hazard to people.
Air becomes extremely unhealthy in some cities since the winter as the presence of pollutant particles in its air even on a normal day is 4-8 times higher than the safe limit.
Air pollution is a major threat to human health worldwide and toxic air pollutants are linked to high risk of stroke, heart ailment, cancer and respiratory diseases, including asthma, experts said.
Higher amount of harmful particles has been found in the air of Dhaka, Gazipur, Narayanganj, Chittagong and Barisal during the winter in different tests.
According to health experts, commuters and pedestrians suffer from various health problems due to air pollution caused by dust and smog in the capital.
Many development works, especially road digging for sewerage line, elevated expressway and flyover, have been taking place in Dhaka.
The development works are producing a huge amount of dust in the city. Many city dwellers are seen wearing masks for protestion against dust.
Experts said air pollutants can go to lungs and cause inflammation immediately.
It can also affect cardiovascular function like heart rate variability, experts said.
Dr Abdul Matin, an associate professor of Shaheed Suhrawardy Medical College, told that problem in respiratory tract, sinusitis, allergy, dust allergy, rhinitis, throat infection, asthma, pneumonia, bronchiolitis, nose blockage, persistent cough and renal damage are caused by breathing dust and unhealthy air.
He said when anyone inhales polluted air, they can develop such diseases. Huge dust has been produced this year due to road digging, he said.
People in Dhaka are facing several problems arising from air pollution. Impact on human health and deterioration of ecosystem are common problem of air pollution in a local margin.
The number of air pollution-related deaths has increased in Bangladesh, says a new report — the State of Global Air 2017 prepared by the US-based Health Effects Institute (HEI). In South Asia, ozone deaths in India are 13 times higher than in Bangladesh and 21 higher than in Pakistan. Ozone-attributable deaths in India are 107,800 while 7,800 in Bangladesh.
Globally, air pollution is estimated to cause more than 4.2 million early deaths. Of them, 1.1 million deaths occur in India alone while 0.12 million in Bangladesh.
Department of Environment Director (air quality management) Ziaul Haque said the presence of pollutant partials in the air of Dhaka and other major cities has usually increased during winter.
Many brick kilns surrounding the capital start their operation during winter, causing air pollution, he said, adding that road digging and construction works also give dust to air and in the winter it becomes unbearable.
“Brick kiln is responsible for 58 percent air pollution while road dust and soil dust 18 percent, vehicle 10 percent, burning biomass 8 percent and other sources 6 percent,” he said. Ziaul Haque said they are trying to check air pollution and have directed the authority to do their development work by taking several precautionary measures.
The monthly average concentration level of PM2.5 and PM10 measured at different CAMS were found 102-237µg/m3 and 166-397µg/m3 respectively during the month of January, 2017, according to Clean Air and Sustainable Environment (CASE) Project.
That concentration level of those was found 86.5-206 µg/m3 and 160-345 µg/m3 respectively during the month of December, 2016. 24-hour average PM levels in all cities monitored are found higher compared to the previous month because of dry season and lower wind speed, it said.
In Bangladesh, the AQI is based on five criteria pollutants — Particulate Matter (PM10 and PM2.5), NO2, CO, SO2 and Ozone (O3). The other levels in AQI are Moderate (51-100), Caution (101-150), Unhealthy (151-200), Very Unhealthy (201-300), and Extremely Unhealthy (301-500).
According to CASE data, the air was extremely unhealthy in Dhaka (416 points in AQI), Narayanganj (821), Gazipur (440), Chittagong (312), and Barisal (349) and Sylhet (237) on January 18. In Dhaka, air quality measure CAMS has been setup in Sangshad Bhaban, Farmgate and Darus-Salam area.