Toxic mix making Delhi a gas chamber: study

A new study on air pollution in Delhi by a team of researchers led by the University of Surrey in the United Kingdom has found the city suffers from a ''toxic blend of geography, growth, poor energy sources and unfavourable weather that boosts its dangerously high levels of air pollution''.

The study also recommends all-round solutions instead of just focusing on vehicular pollution.

The study was recently published in the journal Atmospheric Environment. The team, which includes a professor from IIT Delhi, researched how Delhi's landscape, weather, energy consumption culture, and growing urban population combine to elevate concentrations of air pollutants, including ultra-fine particles, the most harmful to human health.

''Air pollution has been placed in the top ten health risks faced by human beings globally. Delhi has the dubious distinction of being regularly cited as the most polluted city in the world, with air pollution causing thousands of excess deaths in a year in this growing megacity,'' said Dr Prashant Kumar of the University of Surrey.

''While it might be easy to blame this on increased use of vehicles, industrial growth or a growing population, the truth is that Delhi is a toxic pollutant punchbowl with myriad ingredients, all of which need addressing in the round,'' said Kumar.

Classified as the world's fifth 'megacity', Delhi has a population of ''25.8 million'', which continues to grow. With this growth, the study predicted that the number of vehicles would increase from 4.7 million in 2010 to nearly 26 million by 2030.

The total energy consumption in Delhi has risen 57 per cent from 2001 to 2011, said researchers.

According to the report, as a landlocked megacity, Delhi has limited avenues for flushing polluted air out of the city. ''Coastal megacities such as Mumbai have at least a chance to 'replace' polluted air with relatively unpolluted sea breezes, whereas Delhi's surrounding regions are sometimes even more polluted than the city,'' said a statement from the University of Surrey.

''The picture of Delhi's pollution problem is complicated and is aggravated by some factors that are out of human control. However, in this growing city it is important that the population is protected in whatever ways they can be from health-endangering pollutants,'' said Kumar.

''There is also a cultural context … even the best technology will not succeed in reducing emissions and improving air quality if it is not considered in a broader framework of economic development,'' he said.