مارچ 03, 2016
Bangladesh’s national environment agency has rung an alarm bell over air quality in Dhaka, deeming it “extremely unhealthy” as the dry season begins.
On 7 January 2018, Dhaka’s air pollution levels were at 330 on the Air Quality Index (AQI), which is maintained by Bangladesh’s Department of Environment (DoE), branding the capital’s air quality ‘extremely unhealthy’. The air quality had been ‘extremely unhealthy’ for four consecutive days.
Every single day between January 7 and 10, the degree of air pollution in Dhaka went up. On 7 January, air quality in capital was at 330 points according to the AQI. Next day, it was at 341 points, 355 points on January 9, and 372 points on January 10.
The AQI regards the range of 0–50 points as good air quality, 51–100 as moderately good, 101–150 cautionary, 151-200 as unhealthy, a range between 201–300 points indicate very unhealthy, and 301-500 indicates ‘extremely unhealthy’ air quality.
The DoE operates three continuous air monitoring stations (CAMs) in Dhaka – one in Sher-e-Bangla Nagar, one in Farmgate and the last in Darus Salam – to assess air quality. The CAMs monitor the concentration level of pollutants such as carbon monoxide, lead, nitrogen oxide, sulphur dioxide, and PM10 and PM2.5 – this is, respectively, particulate matter (dust, smoke, mist) that is 10 (PM10) and 2.5 (PM2.5) micrometers or less in diameter, respectively. It does not differentiate which precise pollutant is being measured in the AQI.
Nevertheless some pollutants are more worrying than others. In December, the 24-hour average for PM10 and PM2.5 concentrations were higher than Bangladesh’s average air quality standard, the department of the environment (DoE) said in its air quality report.
“The presence of other pollutants is not so serious. But the concentration of PM10 and PM2.5 in Dhaka’s air is most critical. The air quality is aggravating as the dry season arrives,” Ziaul Haque, a DoE director, told thethirdpole.net, adding that the smoke from brick kilns and vehicle emissions are the major causes of PM10 and PM2.5 in Bangladesh.
“If we could curb pollution from these two sources, air quality during the dry season would improve to a large extent,” said Haque.
This is not the first time Dhaka’s air quality has led to public health concerns. In the mega city of more than 16 million people, the air quality falls every year, causing a spike in the number of asthma and respiratory ailments. Dhaka’s air had already been deemed “extremely unhealthy” on 29 November 2017 when the AQI read 374.
Bangladesh has one wet season – from mid-April to mid-October – and one dry season. During the wet season, heavy rainfall occurs across the country. Almost every year rivers, canals, wetlands, low-lying areas – and sometimes mega cities like Dhaka and Chittagong – are inundated. The wind speed during this time is higher than during the dry season. Pollutants, especially particulate matter, are washed away from the air by the rain, improving air quality.
World Bank study
The World Bank has been carrying out a study on Bangladesh’s environment. While the preliminary findings of the bank’s “Unlocking Opportunities for Clean and Resilient Growth” report is yet to be made public, thethirdpole.net has obtained a copy.
According to the report, the health burden of air pollution caused by PM2.5 in urban areas stands at USD 1.93 billion, which is 1% of the country’s gross domestic product. Indoor PM2.5 air pollution causes an additional health burden of USD 1.11 billion, amounting to 0.6% of GDP.
The report states that brick kilns cause 38% of PM2.5 pollution in Dhaka, while motor vehicles cause 19% and road dust causes 18%. Soil dust and pollution from metal smelters account for 9% and 7% of PM2.5 air pollution respectively. Air pollution in Dhaka worsens as brick kilns start production during the dry season, according to the report.
Doctors’ dilemmas versus business opportunities
“The number of patients with asthma and other respiratory diseases reduces sharply with the start of the rainy season,” Rafiqur Rahman, the chief medical officer of the Jatiya Sangsad medical centre, told thethirdpole.net, adding that a strict ban on unfit vehicles in Dhaka would help reduce the national health cost, and the level of illness.
“Children and older people are worst affected by respiratory problems. Poor people who have no access to hospitals and clinics come to us for treatment,” said Mohammad Mohsin, the owner of the Ayesha medicine store in Dhaka’s Mirpur area.
“During the winter, the shopkeepers of many medicine stores start treating people with respiratory problems through nebulizers. When the rain starts, we see a 60% drop in sales of drugs, such as Monas, which are used to treat respiratory problems.”
It is not just the pharmacies and pharmaceutical companies who benefit from the increasing levels of smog in Dhaka – street hawkers also profit.
“In the summer, I sell locally-grown fruits such as mangos, pineapples and guava. But in the winter, I sell masks and handkerchiefs – people buy these to protect themselves from the dust and smoke,” Mohammad Mukul, a hawker, told thethirdpole.net. In Dhaka, hawkers selling masks often board buses stopped at traffic signals or stuck in traffic jams.
Most of the roads in Dhaka are dug up due to the construction of the metro rail and the elevated expressway.
“The authorities should ensure that the dug up portions of the road are covered. When the vehicles move along the road, the dust covers the whole area and people inhale it,” Mohammed Anisuzzaman, a stock market broker, told thethirdpole.net.
Anisuzzaman lives in the Mirpur neighbourhood, where most of the roads are dug up for development works. “Due to severe traffic jams, passengers need three hours to reach Motijheel from Miprpur – a distance of only 14 kilometres – and another three hours for the return journey. Every working day, commuters on the route inhale dust and smoke for six hours,” he said.
Another commuter, Mohammad Hasanul Karim, said that hundreds of trucks carry uncovered sand, earth and bricks in Dhaka after 10pm. When they travel at high speeds, the sand and soil drops on the road.
“In many cases, a layer of sticky soil develops on the road. The frequent movement of the vehicles dries up the layer and makes the soil into dust,” said Karim. “Nobody cares about it.”
It seems there are a variety of small issues that could be tackled to deal with the air pollution hazard, but so far the government has as yet to take the issue seriously.
Kamran Reza Chowdhury is a Dhaka-based journalist