Growing urbanisation and the consequent rise in air pollution is the most serious health hazard around the world. Cities are energy-guzzlers and emitters of polluting gases. Both of these have consequences for the environment which, if not addressed adequately and in time, may lead to loss of economic efficiency of the cities, the very reason for which people flock to them.
The irony of urbanisation cannot be missed in that what leads people to amass in a geographical location could be lost if it proceeds unchecked. So, it is imperative that the civic bodies maintain a fine balance between growth and quality of environment to ensure a good quality of life for the populace. Unfortunately, this is not the case with a majority of Indian cities.
Bengaluru has been on a trajectory of relentless growth since the dawn of economic liberalisation. No city in India has registered such phenomenal growth in terms of municipal area as well as demographic explosion. Though the shrinkage of green cover and deterioration of lakes has evoked considerable concern, ambient air quality has not received similar attention.
Ambient air is atmospheric air in its natural state. It is what one breathes in when the atmosphere is not contaminated by air-borne pollutants. Air gets polluted due to vehicular transport, domestic combustion, industrial processes and unscientific and unsafe disposal of garbage.
If the WHO statistics are any indication, ambient air pollution was responsible for 4.2 million deaths worldwide in 2016. Globally, air pollution is estimated to cause about 16% deaths due to lung cancer, 25% of deaths due to chronic obstructive pulmonary diseases (COPD), about 17% of deaths due to ischaemic heart disease and 24% deaths due to stroke.
The primary air pollutants emitted into the atmosphere are carbon monoxide, sulphur dioxide, nitrogen dioxide, volatile organic compounds, carbonaceous and non-carbonaceous particles. These are released into the air from factories in the form of vehicular emission and use of chemicals in varied forms. Besides, construction activity releases dust while trees are cause for dissemination of pollen and spores into the air. These constitute the particulate matter (PM).
Air Quality Index (AQI) is the authentic guide to check the quality of air on a daily basis. AQI measures the quality on a scale of zero to 500, the higher the AQI value, the greater the level of air pollution and threat to human health. An AQI of 50 represents good air quality with little potential to affect public health. Up to 100 AQI value is rated as ‘Moderate’ and is generally considered as satisfactory.
Anything above 100 is considered ‘Unhealthy for Sensitive Group’ as it may cause discomfort to sick people. Between 151 and 200, it is ‘Unhealthy’ for all. Between 201 to 300, it is rated as ‘Very Unhealthy’ and between 301 to 500 ‘Hazardous’.
The Karnataka State Pollution Control Board (KSPCB) has taken significant steps to generate quality data in the breathing zone at a height of 1.5 metres. This is different from monitoring ambient air quality at six metres height, which does not capture direct exposure to toxic and harmful pollution.
The board maintains Continuous Ambient Air Quality Monitoring Stations (CAAQMS) at seven places in Bengaluru among a total of 21 stations for continuous monitoring, others being monitoring through handheld (manual) particulate pollution meters providing an inexpensive way of performing sampling on a routine or ad hoc basis. The CAAQMS are at BTM Layout, BWSSB-Kadubeesanahalli, Bapujinagar, City Railway Station, Hebbal, Hombegowda Nagar, Jayanagar 5th Block, Peenya, Saneguruvahalli, and Silk Board Junction. The data is webcast every two hours.
While a majority of the CAAQMS show ‘moderate’ air pollution, air quality readings at the City Railway Station and Hebbal generally breach the ‘moderate’ level and court “Unhealthy for Sensitive Group” category. But on festive occasions like Deepavali, the air quality all across the city shoots up and ranges between 130 and 170.
Citizens’ participation
Experience shows that proactive measures such as ‘Bus Day’ organised by the BMTC exert a positive impact and bring down the level of pollutants.
Citizens could chip in by opting for carpooling; switching off lights when not in use, thereby saving energy; unplugging electrical gadgets if constant use is not required (gadgets such as microwave ovens, geysers, etc., consume passive energy); using paints with low or no volatile organic compounds; using natural air-fresheners like essential oils, natural cleansers like lime juice, baking soda; discouraging smokers from smoking indoors; voluntarily giving up private vehicles in favour of public vehicles; growing plants like peace lily, garden mum, aloe vera and participating in tree-planting drives.
And lastly, there is a need for ‘Eco-Spirituality’ for individuals in society. The essence of Eco-Spirituality is living with the truth (ecosystem) with a sense of intimacy, integration, inclusiveness and involvement between oneself and the ecosystem.
(The writers are members of the Bangalore Environment Trust)
