Intro: Delhi has been found to be the worst city in terms of fine suspended particles in the air by the World Health Organisation which can cause serious diseases. To avoid this situation, Government of India has launched a real time Air Quality Index.
While addressing the two day meet of the State Ministers of Environment on April 6 at Delhi, the Prime Minister launched a real time Air Quality Index (AQI). It is a matter of deep concern that the World Health Organisation (WHO) has found Delhi to be the worst city in terms of fine suspended particles in the air. The air that we breathe contains gases, water vapour and particulate matter, dust and biological matter such as viruses, bacterias, pollens etc. While the heavier particles may fall off due to gravity, microscopic particles viz. PM10 and PM 2.5 being so light get suspended in the air for long.
People allergic to different pollutants in the air may develop not only breathing trouble but also more serious diseases. The health impact under the severe pollution level may cause respiratory problems even in otherwise healthy people and serious problems in people with lung or heart disease.
Nano-particles such as those emitted by diesel engines can pass through the cell membrane and thus travel to any organ including the brain. These particles also get loaded with cancer causing chemicals. A large study conducted in Europe found that with every increase of 10 μg/m3 in PM10 and PM 2.5 incidences of lung cancer increases by 22-36 per cent, respectively.
As per WHO estimates fine particulate air pollution causes 3 per cent of all deaths from cardiovascular disease, 5 per cent from cancer of trachea, bronchus and lungs and 1 per cent in children below 5 years of age from acute respiratory infections, worldwide. Traffic exhausts have been found to cause 7.4 per cent of all heart attacks. We must also take into account the deaths and diseases particularly of the housewives in the villages caused by air pollution from burning of firewood and coal etc. It is important therefore, that like the food that we eat and the water we drink, the air that we breathe should also be free from harmful pollutants. It is a time for the government to reconsider subsidy on diesel or make the retrofit diesel engines with diesel particulate filter compulsory. Though, a major step was already taken on April 8, 2015 Delhi has been asked to ban all diesel vehicles older than 10 years by the National Green Tribunal saying, “Pollution level is at an alarming level and residents of Delhi deserve better.” The tribunal also said such vehicles coming from other states should also not be allowed to enter Delhi.
Union Minister of Environment, Forests and Climate Change, Shri Prakash Javadekar on September 17 last year had launched the national Air Quality Index with eight parameters instead of just three that were being monitored earlier. These included PM10, PM2.5, NO2, SO2, CO, O3, NH3, and Pb. AQI is measured on 0-500 points on six ranges from good to severe. Central Pollution Control Board (CPCB) has been monitoring air quality in 127 cities against SO2, NO2, suspended particulate matter and inhalable suspended particulate matter/PM10, but only twice a week. AQI is based upon four centres in Delhi, four cities in UP including Agra, Kanpur, Lucknow and Varanasi, and one each in Andhra Pradesh, Gujarat, Haryana, Karnataka and Tamil Nadu.
Environmental Protection Agency (EPA) of USA is monitoring Air Quality Index worldwide, using New Cast which computes 12 hourly averages but by assigning heavier weightage to the more recent hours, instead of 24 hour flat average. Even Beijing is monitoring AQI in our cities and putting them up on web.
PM (which stands for Particulate Matter Suspended in the Air) may contain nitrates (NO2), sulphates (SO2), organic chemicals, metals, soil and dust. Microscopic Inhalable Suspended Particles viz. PM10-those less than 10 microns or micrometers in size (human hair is 60-70 micron in diameter) may keep floating. Those smaller than 2.5 microns (PM 2.5) are particularly harmful as they maybe inhaled and through lungs get into our blood stream. They also cause fog and haze. These particles contained in soot and smoke etc. may come from wood fires, power plants, industries and automobiles etc. Besides causing health problems they may make lakes and streams acidic; deplete soil nutrients; damage forests and farm crops, river basins and sea coast; and effect the eco-systems. They may also stain and damage stone like marble of heritage sites such as the Taj Mahal. Aerosols (PM mixed with water vapour) effects weather and climate. The failure of the Indian monsoon has been linked to the suppression of evaporation of water from the Indian Ocean due to the semi-direct effect of anthropogenic aerosol
Carbon Monoxide(CO) and Carbon Dioxide (CO2) and Ozone (O3) together with water vapour and methane etc., are the greenhouse gases that makeup the gaseous blanket surrounding the earth. The heat coming from the sun is absorbed on the surface, the warmed surface emits heat which is absorbed and radiated in all directions including back to the earth, by this blanket. By digging up and burning the carbon containing fossil fuels like coal, gas and oil for 80 per cent of energy usage, we are releasing seven billion tons of carbon a year into the atmosphere, thereby thickening the blanket. As a result the earth may also become warmer; the Poles may melt and mean sea level may rise. The climate may change.
Presently, levels of CO2 in this blanket exceed 400 parts per million and is feared to rise to 500 ppm or 1 trillion tons by 2050 almost double of the pre-industrial world. Besides some of the measures suggested in Smart Energy (Organiser dated April 12, 2015), one of the most important ways to arrest this is Carbon Capture and Storage (CCS) back into the earth.
800 power plants of 1 GW each adopting CCS can save 25 billion tons carbon from entering atmosphere over 50 years. The captured gas can be used to take out the remaining oil from the spent fields. Raising capacity factor of 1,600 coal fired plants from 40 to 60 per cent, reducing electricity usage in homes and building by 25 per cent, driving 2 billion cars for half the mileage and at double the fuel economy are some other ways of saving carbon emissions. Still other ways of doing so would increase solar power 700 fold, wind power 80 fold for making hydrogen for cars, and 40 fold to displace coal, increase today’s nuclear energy to twice level etc. Of course if are able to use nuclear fusion to generate electricity or improve the efficiency of Photo Voltaic (PV) cells our dependence on coal and oil would be reduced. Given the huge finds of oil and gas in the western hemisphere, we will continue to use them. But carbon emissions from gas are much less as compared to coal. We must make all out efforts to arrest further increase in carbon emissions.
JP Dubey (The writer is a columnist having expertise on