The quality of the air in the National Capital Region has assumed alarming proportions for the second year in succession. The action that has been initiated by the authorities has turned out to be too little, too late. It reaffirms the gross negligence of the air quality index management. The Indian Medical Association had sounded an alert but the Delhi government passed the buck onto the Centre in terms of its obligation and responsibility, and then referred the matter to the Supreme Court. Despite the National Green Tribunal’s stringent stricture, a respite seems unlikely quite yet. The scenario has deteriorated considerably.

The closure of primary schools, the bar on the entry of trucks, implementation of odd-even vehicle movement in the NCR, creation of artificial clouds for rain are nothing but short-term measures. Concerned over the smog, the NGT has rightly banned all construction and industrial activities in Delhi-NCR and ordered adequate steps to minimise dust contamination by sprinkling water on the roads. Chief Minister Arvind Kejriwal’s tweet describing Delhi as a gas chamber is a simplifistic view of an intricate problem. The maintenance of air-quality standards is the primary duty of both the Centre as well as the state government. It has been a collective and colossal failure of the elected government, technocrats and bureaucrats.

In the wake of the disaster, the Union Environment Ministry constituted a seven-member committee to monitor the menace and recommend curbs. The Central Pollution Control Board (CPCB) and Environment Pollution (Prevention and Control) Authority (EPCA) will go ahead with the course of action after meticulously assessing the current situation. A combination of smoke from stubble -burning in Punjab and Haryana and the seasonal fog have resulted in the hazard. The ‘smog’ thus produced has entered the living rooms and Metro stations as well. ‘Emergency’ under the Graded Response Action Plan (GRAP) has officially been imposed.

The air that Indians breathe is turning more toxic by the day and an average of two deaths occur due to air pollution, according to the noted medical journal, The Lancet. This also substantiates the fact that over a million Indians die or are at the point of death due to air pollution and some of the worst polluted cities of the world are in India, including its capital.

The sub-particulate matter, PM 2.5, is at the root of the problem and climate-change is of course associated with this  phenomenon. The smog, the fog and smoke contamination in northern India is taking a heavy toll; every day two lives are lost because of air pollution.

The index in Delhi, Patna, Kolkata. Mumbai, and Chennai is far from satisfactory.

The Lancet has contradicted some Indian reports and has pointed out that coal-fired power plants contribute to 50 per cent of the external pollution. The emissions from vehicles, specifically the polynuclear aromatic hydrocarbons (PAH), are extremely carcinogenic. The report has mentioned the risk to human health and the need for effective environment management. This is direly imperative. According to WHO and UNEP (United Nations Environment), pollution in Delhi and Kolkata have reached alarming levels. The air we breathe is poisoned with anthropogenic and natural emissions. However, this is not a new problem. As long as man has lived in cities, he has developed a propensity to pollute the air. It is a problem that has emanated from a technological society. Climate-change has aggravated the situation.

Artificial impurities are largely injected into the atmosphere at or near the earth’s surface. The pollutant cleanses itself within a very short period because of the so-called “vertical missing ability”. Rain also helps remove the impurities, but acid rain can damage the environment. Therefore, any substance that is not part of the air’s “gaseous make-up” is regarded as a pollutant. Air-borne suspended particulate matter (SPM), respiratory particulate matter (RPM) and contaminant gases exist in the atmosphere in various degrees. Air pollution is not confined to a particular territory but is a trans-boundary phenomenon. In major urban cities of India, the quality of the air has been deteriorating rapidly over the past two decades.

The problem is particularly acute in the cities and suburbs where the air is unclean, according to the standards fixed by the World Health Organization. The burgeoning population is also a contributory factor. Emission from vehicles has been identified as the major source of pollution in the Delhi metropolitan region. It is responsible for nearly 60 per cent of the city’s total pollution level. The situation is appalling owing to the increasing number of vehicles and the limited space for their movement.

Domestic consumption of fossil fuels, sometimes out in the open, and pollutants from small industries and godowns, multistoried buildings and road construction, burning of agricultural waste, emission of SPM from thermal power stations are further accentuating the problem. The pollutants vary from one place to another. Its intensity is the highest in the heart of the city. The common air pollutants in Delhi are sulphur dioxide, oxides of nitrogen, carbon monoxide, hydrocarbons, peroxy acetyl nitrite (PAN) which cause irritation of the eyes, heavy metals and traces of the dangerous polynuclear aromatic hydrocarbons (PAH) which are carcinogenic in character.

The poor are acutely affected by pollution. The pavement dwellers, underprivileged and vulnerable groups are exposed to direct health hazards. In addition, the heavy air pollution leads to higher rates of mortality and morbidity. Lead petrol has been banned in most developed countries. But unleaded petrol has other disadvantages which need special attention. Lead-free petrol releases a higher level of aromatic organic compounds and a high concentration of benzene which is known to be potentially carcinogenic. According to WHO, the risk of cancer is substantial. Suitable measures need to be taken immediately to eliminate the emission of toxic benzene into the air.

How is it that millions manage to survive? One probable explanation is that the air pollutants are shared by millions of people and they act as biological filters. The body doesn’t immediately suffer any symptoms of danger, but they do arise after a prolonged period of time. The entire auto-emission regulatory process needs to be revamped immediately. Reduction of vehicular emissions through continuous check, strict enforcement of the law and periodical survey of the emission control equipment are imperative. The use of catalytic converters inside a

car exhaust system also has its benefits.

The use of lead-free petrol in cars without converters is a great risk to public health. Personal exposure to benzene at service stations should be minimised. All service stations must display warnings about the risk of benzene exposure. The vehicles that are running on outdated technology should be immediately abandoned. Planting more trees in the city can cleanse the air. The quality of fuel used in automobiles also helps curb air pollution.

Its samples need be analysed regularly. Finally, the success of mitigating air pollution depends largely on popular participation and awareness of the environmental health hazards emanating from auto-emission.

The writer, a former Reader in Chemistry at Presidency College, Kolkata, was associated with the UGC and UNICEF