Context   A recent study conducted by IIT Delhi in collaboration with Universities of California, Illinois and the Delhi based NGO Urban emissions has pointed out that the use of firewood, kerosene and also coal in the households contributed to about 40% of the PM 2.5 pollution in the Gangetic basin districts.   Background concepts to understand the issue   Concept 1: Particulate Matter 2.5 (PM 2.5)  

  • The particulate Matter 2.5 (PM2.5) refers to tiny particles or droplets in the air that are two and also approx one half microns or less in width.
  • PM2.5 pollutants are able to travel deeply into the respiratory tract, reaching the lungs and can cause several respiratory and cardio-vascular problems like lung irritation, shortness of breath, asthma and also heart disease.
  • In fact, there are outdoor and also indoor sources of the fine particles. Outside, fine particles primarily come from vehicular pollution, burning of fuels such as wood and coal and natural sources such as forest and grass fires. PM2.5 is also produced by common indoor activities like tobacco smoke, cooking with inefficient fuel like wood, etc.
  • It is more severe in urban areas
  • According to NAAQS, PM 2.5 should be below 40 micrograms/cubic meters. However, according to a 2017 Report, it averages around 125 micrograms/cubic meters in India.
  Concept 2: National Ambient Air Quality Standards (NAAQS)  
  • The ambient air quality (AAQ) refers to the condition or quality of air surrounding us in the outdoors.
  • National Ambient Air Quality Standards are the standards for ambient air quality set by the Central Pollution Control Board (CPCB) that is applicable nationwide (The CPCB has been conferred the power by the Air (Prevention and Control of Pollution) Act, 1981). It includes the following pollutants:
  1. SO2 (Sulphur dioxide)
  2. NO2 (Nitrogen dioxide)
  3. PM10
  4. PM2.5
  5. O3 (Ozone)
  6. Pb (Lead)
  7. CO (Carbon monoxide)
  8. NH3 (Ammonia)
  9. Benzene
  10. Benzo(a)Pyrene (BaP)- particulate phase only
  11. As (Arsenic)
  12. Ni (Nickel)
  • Furthermore, a new National Air Quality Index (NAQI) was launched in the October in the year of 2014 to disseminate information on air quality in an easily understandable form for the general public.
  • The measurement of air quality in AQI is based on eight pollutants. These are underlined in the list above.
  The Issue   Highlights of the Report    
  • The results showed that by eliminating household emissions the average outdoor air pollution levels could be reduced and PM2.5 could be brought within the NAAQS limits.
  • The mitigating at a household level is the easiest and also more practical way out for the government to reduce not only the household pollution but also the outdoor air pollution at the national scale.
  • The mitigating the use of household fuels can also reduce the air pollution-related deaths in the country by approx 13%, which is equivalent to the saving about 270,000 lives a year.  
  Case of Delhi NCR   However, even if this was achieved in the NCR, it would still not help achieve the pollution targets as several other factors complicate the issue for NCR:
  • Stubble burning in neighboring states
  • Industrial and power plant emissions
  • Brick kilns
  • Vehicular emissions
  Although most of these issues plague other areas as well, NCR is severely affected due to high density of these activities and there being no outlet due to land locked location of the NCR.   Accordingly, although eliminating household emissions will be a step in the right direction, the NCR needs a more multi-pronged approach to overcome the scourge of pollution.   National Clean Air Programme (NCAP)  
  • An initiative to contain PM 2.5 and other pollutants has already been started in 2019 under the NCAP. In fact, it is the time bound national level strategy for pan India implementation to tackle the increasing air pollution problem across the country in a comprehensive manner.
  • And the tentative national level target of approx. 20% - 30% reduction of PM2.5 and PM10 concentration by 2024 is proposed under the NCAP taking 2017 as the base year for the comparison of concentration.
    Vantage Point for PT   Well, in the cities of our country, which among the following atmospheric gases are normally considered in the calculating the value of Air Quality Index (AQI)?
  1. Carbon dioxide
  2. Carbon monoxide
  3. Nitrogen dioxide
  4. Sulphur dioxide
  5. Methane
Now select the correct answer using the code which is given below. (a) 1, 2 and 3 only (b) 2, 3 and 4 only (c) 1, 4 and 5 only (d) 1, 2, 3, 4 and 5   Explanation:   This question was asked in PT’2016.  In the National Air Quality Index, there are six AQI categories, namely Good, Satisfactory, Moderately polluted, Poor, Very Poor, and Severe. And, the AQI (Air Quality Index) considers the eight pollutants (PM10, PM2.5, NO2, SO2, CO, O3, NH3, and also Pb) for which short-term (up to 24-hourly averaging period) the National Ambient Air Quality Standards (NAAQS) are prescribed. So, the correct answer is (b).   Smart Strategy: Please also note that Carbon dioxide is not in the AQI (or even NAAQS) list. If you remembered this fact alone, then the above question could have been answered by elimination. CO2 is mentioned in options (a), (c) and (d) and hence, they all get eliminated, leaving you with the right answer which is (b).