Dr Arun Mitra
Unprecedented high levels of air pollution in north India during the months of October and November in 2017 raised serious alarm in the society as well as the government. This is because health is directly related to clean air quality besides clean drinking water and other causes that affect our surroundings. Therefore, every year during the months of October and November there is serious discussion on air quality, which is disturbed as the summer ends and winter sets in. For the last several years dense smog engulfed large part of north India including Punjab, Haryana, western UP, parts of Rajasthan, Himachal Pradesh and NCR Delhi during the months of October and November when summer ended and winter was about to set in. During the summer season air tends to go up in the atmosphere. But during October and November, because of fall in temperature, the particles do not rise in the atmosphere. They get suspended and mix with vapours. The sources of these particles are mainly vehicular emissions, industrial effluents and smoke coming out of burning of paddy straw in the fields. Low wind speed during this period and dry weather aggravate the problem.
As a result, there is a drop in the air quality, some times to dangerous levels. Air quality is measured as Air Quality Index (AQI). As per the Environmental Protection Agency (US), the AQI is calculated on the basis of five major pollutants – the ground level ozone, particulate matter, carbon monoxide, sulfur dioxide and nitrogen dioxide. The AQI levels have been graded in the range of 0-500. AQI levels from 0-50 are satisfactory and pose little or no risk. Moderate AQI is from 51-100. This poses risk to a very small number of people, particularly those who are sensitive to ozone. The levels from 101-150 can be harmful to persons who are already suffering from respiratory problems or heart diseases; children and elderly are at higher risk. From 151-200 are unhealthy levels for every citizen while the sensitive groups may experience more serious effects. Levels between 201 and 300 are health alert for more serious effects. AQI levels beyond 300 are an emergency situation. In this context the levels, which went up to 999 in the Punjabi Bagh area of Delhi on 8th November 2017, caused serious alarm.
Smog causes a feeling of suffocation, which occurs due to relative lowering of oxygen level in the surrounding air. The pollutants in smog can irritate respiratory system, causing coughing and feeling of irritation in throat. One may experience an uncomfortable sensation in the chest. The ozone in the smog can reduce lung functions and make it more difficult to breathe deeply and vigorously. There is aggravation of asthma, which may require medication. Ozone makes people more sensitive to allergens, which are the most common triggers for asthma attacks. It can aggravate chronic lung diseases such as emphysema and bronchitis and reduce the immune system’s ability to fight off bacterial infections in the respiratory system. Repeated short-term ozone damage to children’s developing lungs may lead to reduced lung function in adulthood.
Particulate matter includes microscopic particles and tiny droplets of liquid. Because of their small size, these particles are not stopped in the nose and upper lungs by the body’s natural defences but go deep into the lungs, where they may become trapped and cause irritation. Exposure to particulate matter can cause wheezing and similar symptoms in people with asthma or sensitive airways. Particulate matter can serve as a vector for toxic air pollutants. Carbon monoxide affects oxygenation of Hemoglobin by forming Carboxy-Hemoglobin.
As a result of all these there is loss of man days because the working capacity of the person goes down. Children are not able to attend school. Since the medical advisory in extreme circumstances like last year is to avoid outdoor activity, the productivity falls. In addition the health problems are aggravated as a result of accidents.
The time gap between harvesting of paddy and sowing of wheat crop is less. Therefore, the easiest method the farmers find is to burn the straw and then plough the field for the next crop even though the high temperature over the soil because of burning of straw residue destroys useful microorganisms causing huge loss of nitrogen, phosphorous, potash and many beneficial micro nutrients. As per estimates, there is loss of macro and micro nutrients to the tune of Rs.1,000 crores in Punjab alone per year due to burning of wheat and paddy straw. According to agricultural experts, paddy cultivable area in Punjab is about 65 lakh acre. On an average there is 30 quintal of yield per acre, which means 19.50 crore quintal of paddy is produced in the state. Different types of agricultural machinery required for management of straw, as per the guidelines of the NGT, costs around Rs 1,600 crores for Punjab. The central government had allocated only Rs. 695 crore to be given in two years. It is not possible for small and marginal farmers, who form nearly 1/3rd of land holdings, to purchase such machinery.
It is not correct to put the whole blame on farmers without addressing their grievances. The farmers have a feeling that by delaying the sowing of the next crop they are losing money due to reduced yields. Some experts suggest that if farmers are given a bonus of Rs.100 per quintal, which will cost the government around Rs 2,000 crores, there is a possibility that farmers could be convinced to shun this practice. Many young farmers are now concerned about the fertility of the soil as well as the health effects of smoke. The state and the central governments should share this responsibility. The overall cost has to be evaluated with the health cost borne by the people, which could be much higher because it involves cost on disease, loss of man days, loss of production, loss of schooling and mental stress.
The Punjab Government has taken initiative for Mission Tandrust Punjab (mission healthy Punjab) project. Special task forces have been made to check burning of paddy straw, which is one of the biggest sources of deterioration of air quality during this period. The government has also introduced special machines to harvest and cut the straw of the paddy into small pieces so that these can be ploughed in the fields. The Government has allocated subsidy on all types of straw management equipment to the extent of 80% where the farmers have formed groups and 50% for single farmers. This is a very welcome step and we expect positive outcome. More combines are needed fitted with straw management system, which will chop the straw and make it easy for the farmers to plough.
In addition, other urgent remedial measures have to be taken. The industry needs to be regulated firmly to reduce effluents. Vehicular emissions have to be brought down. We hope better quality air compared to last year in the coming few weeks. (IPA)