Insufficient Air Quality Data
The city does not have required number of monitors to give us the real picture on air quality.
Map with locations of existing monitors
How is Bengaluru’s air quality monitored?
The city of Bengaluru currently has 23 air quality monitoring stations, of which 13 are manual stations and 10 are continuous stations. These operate under the National Air Quality Monitoring Programme, which is a national network of air quality monitors run by the Central Pollution Control Board. The monitors measure air quality including four pollutants – SO2, NO2, PM10 and PM2.5
What is the problem with the current set-up?
The number and distribution of monitors in a city determine the robustness of the air quality data available. There are different standards for assessing the right number of monitors, which consider the population, the size of the city, the type of pollutants to be measured, the variability of pollution concentrations, health implications for citizens, etc. Other factors which contribute to additional requirements are heavy industrialisation, heavy fuel usage, irregular terrain, high vehicular density and population density. A study by Air Pollution Knowledge Assessment states that the city air shed requires at least 41 continuous air monitoring stations (CAMS) to statistically, spatially, and temporally, represent the mix of sources and range of pollution in the city. Additional issues are in where these air quality monitors are located and the distribution network in the city, as well as in the accessibility of the data that these monitors generate for both citizens as well as researchers.
Gap in continuous monitors in Bengaluru as well as the larger region (APnA City Study, 2017)
How will enhancing the monitoring network help?
An improved air quality monitoring network will aid:
- Citizens to understand the air quality in their neighbourhoods
- Government departments to make informed decisions during project planning and take suitable mitigation measures
Inadequate understanding of sources of pollution
With no emission database, we don’t know the sources which contribute the most.
Sources of Air Pollution in Bangalore: TERI, 2010
A study by The Energy and Resources Institute (TERI) in 2006 revealed that vehicular pollution is the primary source of the dangerous PM2.5, which is inhalable particulate matter so fine, it is 30 times smaller than the width of a single strand of hair! A decade later, an Urban Emissions (UE) research in 2015 showed that vehicular exhaust and on road dust re-suspension, contributing to 56 percent of the PM2.5 levels. Vehicular pollution is consistent as the major contributor, while construction dusts replaced diesel generators as the second highest contributor.
PM, or particulate matter, is a mixture of solid particles and liquid droplets that is found in the air. The size of these particles gives rise to its name – so those with diameters less than 10 micro-metres are known as PM10, and those with diameters under 2.5 micro-metres are known as PM2.5. The smaller the particles are, the more harmful is the pollutant, since they are able to overcome the body’s natural defence barriers like nasal hair, mucous lining, etc and reach the lungs, from where they enter the blood stream.
PM stands for particulate matter, the term for a mixture of solid particles and liquid droplets found in the air. Some particles, such as dust, dirt, soot, or smoke, are large or dark enough to be seen with the naked eye. Others are so small they can only be detected using an electron microscope.
- PM10: inhalable particles, with diameters that are generally 10 micrometers and smaller; and
- PM2.5: fine inhalable particles, with diameters that are generally 2.5 micrometers and smaller.
How small is 2.5 micrometers? Think about a single hair from your head. The average human hair is about 70 micrometers in diameter – making it 30 times larger than the largest fine particle.
Source: United States Environmental Protection Agency
Insufficient low-cost sensor ecosystem
Low cost sensors are not accepted by regulators, while there is no independent evaluation of sensors.
For a large, densely populated city like Bengaluru, with complex land use patterns and distribution of traffic congestion hot-spots, the number of air quality monitors required is much higher than what we currently have. The city has 11 continuous air quality monitoring stations, which are not sufficient if one has to understand the spatio-temporal distribution of pollutants.
The hurdles in setting up more reference grade air quality monitors in the city are many, including difficulty in the government acquiring land, and more importantly the extremely high costs – a monitoring station which measures the four basic pollutants – SOX, NOX, PM10 and PM2.5 costs upward of INR 50 lakh.
A solution to this is the use of low cost monitors, which start close to INR 4000, and allow individuals and organisations to take monitoring into their own hands. However, because of a lack of calibration or certification protocol in India, the data from the low cost monitors is not considered reliable, and is not admissible for it to be published or acted on formally.
Policy & administrative challenges
Policy makers lack the evidence and capacity to tackle air pollution through a multi stakeholder approach.
The most important legislation in India aimed at monitoring and curbing air pollution is the Air (Prevention and Control of Pollution) Act, 1981. This law provides for the establishment of Central and State Pollution Control Boards entrusted with the responsibility of monitoring and reducing air pollution in India. These pollution control boards monitor various components of air pollution, such as the sulphur dioxide, nitrogen oxide, suspended particulate matter (SPM) and respirable particulate matter (RPM) content in the air to assess it. However, these bodies have become toothless tigers and have been unable to effectively reign in air pollution in the country. This is attributable to many factors, but the most important is the lack of sufficient enforcement and penalization powers of these Pollution Control Boards.
The fact that the sources of air pollutions cut across the jurisdictions of various government departments and agencies (like transport, construction, garbage collection, etc) poses further challenges in administration.
Limited citizen involvement
With not enough information on exposure and health impacts, the public perceives ambient air to be good.
Why do we need to engage the citizens?
An analysis of ambient air quality data from official monitoring stations of Karnataka State Pollution Control Board (KSPCB) by the Centre for Science and Environment (CSE) has shown an increase of 57% in particulate matter between 2010 and 2014. It also found that the citizens were exposed to much higher levels of PM2.5 than the permissible limits. Despite having an air quality comparable to that of Delhi’s if not worse, Bangalore finds it more acceptable than Delhi does. But why such a difference in the perception?
This false perception towards air quality can be attributed to many factors like lack of sufficient real-time data and access to it, low knowledge and awareness about the concept of AQI, ambient air quality and particulate matter (PM2.5, PM10), and the difference in the visibility of air pollution. While Delhi regularly gets shrouded in a veil of haze and smog without fail every year, Bangalore’s sky stays blue and clear almost around the year. Unlike Delhi and other cities in the Northern Plain where the infamous air pollution is also partly due to crop burning in the surrounding areas, Bangalore has no such external phenomenon to blame. In fact, the majority of air pollution in the city is due to vehicular emissions, waste burning and dust due to construction, given how rapidly the city is expanding and urbanizing. Many in the city are also under this impression that whatever respiratory or allergic ailments they get are due to high pollen concentrations, which may be true but it is also due to bad air quality.
This calls for making the citizens of Bangalore aware of how bad the city’s air quality is, why it is so, its potential health impacts and what they can do collectively and individually to make their air breathable.
Those affected worst contribute the least and are under-represented in decision making.
The report on Global Burden of Disease (GBD) estimates 2 million premature deaths annually in India due to ambient air pollution and household air pollution exposure (GBD (Global Burden of Disease), 2016). This places air pollution near or at the top of the list of all known risk factors for ill health in the country, above high blood pressure, smoking, child and maternal malnutrition, and risk factors for diabetes. However, given the current demographics in India skew towards a more youthful population, there may be a masking of the cumulative cardio-pulmonary effects of air pollution exposures, that will only be observable as latent effect decades later. If PM2.5 levels were to remain constant at current levels, it would suggest that the per-capita mortality attributable to PM2.5 in India would increase by 21% in the year 2030, aided and abetted by a dramatic increase in the age > 50 population. To even keep PM2.5 -attributable mortality rates (deaths per 100,000 people per year) constant, the average PM2.5 levels would need to be reduced by 20-30% over the next 15 years, particularly to reduce the increases in PM2.5 – attributable mortality in the elderly. Thus, significant improvements in indoor and outdoor air quality are required to produce a significant reduction in PM2.5 -attributable mortality in India (Apte et al., 2015).
These health impacts are uniform across citizens, but there are certain populations which are more vulnerable and exposed. These include children and elderly, those who have jobs which require them to be in places of high exposure like traffic policemen, driver particularly of buses and autos, municipality workers on ground, security guards, etc. Interestingly, athletes and fitness enthusiasts who exercise outdoors are also at a higher risk.