Qualité de l’air à Battaramulla

Is Battaramulla badly affected by air pollution?

Battaramulla is located in the suburbs of Colombo, the commercial capital of Sri Lanka and the largest city by population size. It is considered as one of the fastest developing areas within the extended Colombo district (one of twenty five different districts present throughout the country), and is home to many places of administration and business, as well as having large residential areas that are shared by many important figures and government officials.

Regarding the quality of Battaramulla’s air, it has come in repeatedly over the years with a poor level of air pollution present, placing it into the upper echelons of the worlds most polluted cities as of 2020, in fact making its way into the top 500 most polluted cities, coming in at 486^th place with its yearly PM2.5 average reading of 27.1 μg/m³.

This reading would classify Battaramulla as being in the ‘moderate’ pollution bracket, which requires a PM2.5 reading of anywhere between 12.1 to 35.4 μg/m³ to be classified as such. This rating is color coded as yellow, as per all the air quality maps and graphs in use throughout the IQAir website, and indicates a level of air pollution whereby the general public may not be at any major risk, however vulnerable individuals may start to experience respiratory irritation and other related illnesses.

In late May and early June of 2021, a serious incident occurred off the coast of Colombo, with a cargo ship carrying large amounts of chemicals and plastic materials catching fire. Whilst the fallout from this will be discussed in more detail, the resulting pollution given off has devastated the local environment and coastline in which it occurred. Many chemical compounds and fine particles not typically seen from ‘regular’ pollution sources (such as cars, factories and the burning of organic matter) would have been released into the atmosphere, many of which would have a severe impact on the various ecosystems in the area, as well as having grave effects on the health of Colombo’s citizens, and any surrounding areas where the vast clouds of smoke may have drifted.

Whilst PM2.5 has already been used as a unit of measurement as shown above (due to it being one of the most dangerous forms of air pollution present and thus a salient measure of the air pollution level, especially when used to calculate yearly averages), US AQI is also used prevalently. US AQI itself is a number aggregated from the volume of several main pollutants typically found in the air, with PM2.5 being one of these components, along with nitrogen dioxide (NO₂), sulfur dioxide (SO₂), ozone (O₃) and PM10, a larger or more coarse form of particulate matter that can still cause many health symptoms to those who are exposed, yet is of significantly less danger than PM2.5 due to the size difference.

In early June of 2021, whilst the ship fire incident was still making headlines around the world, Battaramulla presented with a US AQI reading of 80, placing it into the higher end of the ‘moderate’ pollution bracket. Whilst the moderate rating used in PM2.5 rankings is taken in microns per meter cubed (μg/m³), US AQI uses a different ratings system, with moderate air pollution levels requiring a reading of anywhere between 51 to 100 to be classified as such. Whilst this reading of US AQI is not overtly disastrous by any means, there are numerous pollution readings on record from past years that show that Battaramulla does indeed have a significant problem with its air quality levels, with the reasons why being discussed in short.

Has Battaramulla been affected by the ship fire off the coast of Colombo?

Whilst Battaramulla has not been directly affected due to the greater distance from the coastline off Colombo, the resulting fallout from this disaster will cause many ongoing issues, with industries such as tourism (already badly affected by the covid-19 outbreak) and fishing being seriously disrupted, with surrounding areas of the coastline having been permeated by large amounts of chemical granules and plastic pellets. The result is that the damage has tended more towards the water and land, and although the air quality would have been at an extremely dangerous level whilst the fire raged on (before it was doused on a Friday of late May), strong coastal winds would have been quick to blow the resulting plumes of smoke away, with any resulting long term effects from these air pollutants having yet to be witnessed.

Other significant causes of air pollution in Battaramulla include the massive overuse of cars, with many of them being old and of extremely poor quality, due to less stringent road regulations present in Battaramulla and throughout Sri Lanka. Others would be emissions from factories and power plants, along with burning organic material such as wood, charcoal or even dried animal dung in certain households, with the resulting smoke clouds causing large spikes in the PM2.5 levels throughout the region.

What are some of the different types of pollution found in Battaramulla?

Besides the main chemicals that go into the US AQI collective, other ones present would be ones such as black carbon and volatile organic compounds (VOCs), both of which are formed from the incomplete combustion of fossil fuels as well as organic material. Black carbon is the main component of soot and would thus be released in large quantities by vehicles and other combustion sources.

Huge amounts of both of these would have been released from the ship fire, with some examples of VOCs including chemicals such as benzene, formaldehyde, styrene and xylene. Other highly dangerous contaminants that would have been released would be microplastics, burnt plastic fumes, dioxins, furans, and heavy metals such as lead and mercury, along with polycyclic aromatic hydrocarbons.

When does Battaramulla have its worst pollution levels?

Observing the pollution levels collected over the course of 2020, it can be seen that Battaramulla had a distinct period of time in which the PM2.5 count was much higher than the rest of the year. The first three months all came in with elevated numbers, with January through to March coming in at 38.7 μg/m³, 45.8 μg/m³ and 41.8 μg/m³ respectively.

These readings placed the months into the ‘unhealthy for sensitive groups’ bracket, which requires a PM2.5 reading of anywhere between 35.5 to 55.4 μg/m³ to be classified as such. This is color coded as orange, same as the US AQI equivalent (which requires its own level of entry at 101 to 150 on the US AQI scale). This indicates that the first three months of the year would have the highest levels of haze, smoke and hazardous clouds of fine particles present, causing respiratory distress to both the general public and those with pre-existing health conditions.

Does Battaramulla see an improvement in its air quality?

Battaramulla has shown a poorer level of air quality from 2019 through to 2020, coming in with a yearly average of 21.4 μg/m³ in 2019, followed by 27.1 μg/m³ in 2020. This indicates that despite heavily reduced movement and tourism in 2020 due to covid-19, Battaramulla still managed to maintain higher levels of air pollution.

However, over the course of 2020, Battaramulla did show small improvements throughout the year, with the months of May through to September coming in with lower readings of PM2.5, indicating a better quality of air. Out of all of these months, September came in with the cleanest reading at 15.7 μg/m³, only a few units from being moved down to the ‘good’ air quality ratings bracket (color coded as green and requiring a PM2.5 reading of 10 to 12 μg/m³ to be classified as such).