Severe air pollution is choking Dhaka – but much of it could be easily tackled

Bangladesh’s national environment agency has rung alarm bells over air quality in Dhaka, deeming it “extremely unhealthy” as the dry season begins.

On January 7, 2018, Dhaka’s air pollution level was at 330 on the Air Quality Index, which is maintained by the Department of Environment, branding the capital’s air quality “extremely unhealthy”. The air quality had been “extremely unhealthy” for four consecutive days.

Every day between January 7 and 10, the degree of air pollution in Dhaka went up. On January 7, air quality in the 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 as cautionary, 151-200 as unhealthy, 201–300 points as very unhealthy and 301-500 as “extremely unhealthy”.

The environment department operates three continuous air monitoring stations, or CAMs as they are better known, in Dhaka – at Sher-e-Bangla Nagar, Farmgate and Darus Salam – to assess air quality. The CAMs monitor the concentration levels of pollutants such as carbon monoxide, lead, nitrogen oxide, sulphur dioxide as well as PM10 and PM2.5, which refers to particulate matter (dust, smoke, mist) that is 10 and 2.5 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 environment department 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,” Ziaul Haque, the environment department’s director, told The Third Pole, adding that the smoke from brick kilns and vehicle emissions was 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.”

This is not the first time Dhaka’s air quality has led to public health concerns. In this mega city of more than 16 million people, air quality falls every year, causing a spike in asthma and respiratory ailments. Dhaka’s air had already been deemed “extremely unhealthy” on November 29, 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 speeds during this time are 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 are yet to be made public, The Third Pole has obtained a copy.

According to the report, the health burden of air pollution caused by PM2.5 in urban areas stands at $1.93 billion, which is 1% of the country’s gross domestic product. Indoors, PM2.5 air pollution causes an additional health burden of $1.11 billion, amounting to 0.6% of the GDP.

The report states that brick kilns cause 38% of PM2.5 pollution in Dhaka, while motor vehicles cause 19% and road dust 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’ dilemma

“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, said, 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 and poor people who have no access to hospitals and clinics come to us for treatment,” said Mohammad Mohsin, owner of Ayesha medicine store in Dhaka’s Mirpur area. “During the winter, many medicine stores start treating people with respiratory problems through nebulisers. When the rain starts, we see a 60% drop in the sales of drugs such as Monas, which are used to treat respiratory problems.”

It is not just pharmacies and pharmaceutical companies that benefit from the increasing levels of smog in Dhaka – street hawkers do too. “In the summer, I sell locally-grown fruits such as mangos, pineapples and guava,” Mohammad Mukul, a hawker, said. “But in the winter, I sell masks and handkerchiefs – people buy these to protect themselves from the dust and smoke.”

In Dhaka, hawkers selling masks often board buses stopped at traffic signals or stuck in traffic jams.

Irresponsible behaviour

Most roads in Dhaka have been dug up for the construction of the metro rail and the elevated expressway. “The authorities should ensure that the dug up portions of the road are covered,” Mohammed Anisuzzaman, a stock market broker, said. “When the vehicles move along the road, the dust covers the whole area and people inhale it.”

Anisuzzaman lives in the Mirpur neighbourhood, where most roads have been dug up for development works. “Due to severe traffic jams, passengers need three hours to reach Motijheel from Miprpur – a distance of only 14 km – 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 hundreds of trucks carry uncovered sand, soil and bricks in Dhaka after 10 pm. When they travel at high speeds, the sand and soil drops onto the roads. “In many cases, a layer of sticky soil develops on the road,” he said. “The frequent movement of the vehicles dries up the layer and makes the soil into dust. Nobody cares about it.”

It seems there are a number of small problems that could be tackled to deal with the air pollution hazard, but so far the government has not taken them seriously.

Kamran Reza Chowdhury is a journalist based in Dhaka.

This article first appeared on The Third Pole.