New Delhi is not the most polluted city in the world, the head of environment measurement index said, denying previous reports that claimed the Indian capital to have surpassed Beijing's pollution levels.
The Environmental Preference Index did not have comparative data - a crucial factor for ranking cities, head of the organisation Dr Angel Hsu, told BBC. But there is no denying that New Delhi is highly polluted. India still ranks among the 178 highly polluted countries. India was at 174 and China at 176.
Dr Gufran Beig, chief scientist at India's System of Air Quality Weather Forecasting and Research, also did not agree with the report. He said the average concentration of smaller dust particles (PM2.5) - that penetrate directly into the lungs - was 210 microgram per cubic metre (m/cum) in Delhi this month. This means that it was not even half of Beijing's PM2.5 level that was recorded this year.
Yale and Columbia University researchers prepare the Environmental Preference Index. "The EPI does not rank cities, nor do the data in the EPI provide any information on city-level performance," said Dr Hsu of the Yale Center for Environmental Law and Policy, who is also the project director of the index.
He said that they had no data from India. "Beijing reports [pollution] data on an hourly basis over a publicly accessible platform. Delhi's reporting is not as consistent or transparent, making direct comparison impossible. Delhi may or may not have dirtier air than Beijing, but it is clearly behind in how it makes air quality information available to its citizens," Dr Hsu added.
"Our pollution levels do not need to get worse than Beijing's for us to wake up and take action. Delhi's air is bad, very bad, and it's getting worse by the year," Dr Sarath Guttikunda, director of Delhi-based Urban Emissions Info said, reports BBC.
