Dangerous haze

Action overdue on poor-quality city air

Come Diwali and the air quality in urban centres, notably in northern states including Delhi - already unfit to inhale - dwindles even further. The menace of air pollution around this time, though a recurring curse, is worse this year because of a combination of factors, many of which have remained unaddressed over the years. The festival of lights has coincided with the onset of winter and the paddy harvest season when the farmers tend to burn the residual crop stubble in their bid to get the fields ready in time for planting rabi crops. Besides, the humidity level in the air has also surged this year in the wake of a western disturbance that caused early snowfall in the hills and light rains in several northern states. These factors, coupled with the usual rise in pollution due to increased vehicular traffic and bursting of firecrackers around Diwali, results in the formation of smog that tends to hang closer to the ground, posing health hazards.

Unsurprisingly, hospitals are flooded with patients complaining of aggravation of asthma, bronchitis, wheezing and chronic obstructive pulmonary diseases (COPD). Doctors maintain that smog carrying high levels of fine particulate matter measuring less than 2.5 micrograms per cubic metre (PM 2.5), which can penetrate into the lungs, causes constriction of arteries and loss of oxygen in the blood to trigger angina and heart attacks. Worryingly, the level of PM 2.5 in the Delhi air in recent days has hovered between 200 and 500 micrograms which is three to eight times the safe limits. Even otherwise, a recent international study found that Delhi, followed by Patna, was the most polluted city in the world. Of the 20 most polluted cities, 13 were in India.

Action to check pollution, improve air quality and mitigate ill-effects on health has to be on several fronts. Curbing farm fires is a must to reduce the level of smoke that, in turn, triggers formation of even more perilous smog. Satellite images of north India released by the US National Aeronautics and Space Administration (NASA) over the years have shown that the incidence of biomass torching in Punjab, Haryana, and parts of Uttar Pradesh and Rajasthan is increasing rapidly. Though most of these states have in place the laws to stop burning of agricultural biomass, these laws are seldom enforced in order not to annoy farmers. Apart from the smoke, local emissions from the transport sector, firecrackers and other sources too need to be curbed. The number of polluting vehicles in Delhi is steadily swelling, and market-based solutions need to be found to this problem. This apart, an intensive public education campaign is needed to reduce pollution from fireworks and crackers. Such campaigns in the past, which focused specially on schoolchildren, had shown good results. At the individual level, the doctors advise people suffering from respiratory ailments to stay indoors as much as possible. The government, on its part, needs to constantly monitor air quality and issue suitable advisories for people to mitigate its adverse effects.