Significant ozone built up in Delhi poses health risk: CSE

New Delhi: A significant ozone build up has been witnessed this summer in several areas of the national capital, including the one where Delhi Chief Minister Arvind Kejriwal resides, increasing the public health risk, a green body warned Thursday.

A latest analysis done by Centre for Science and Environment (CSE) on the eve of World Environment Day on June 5 found that the area where Kejriwal resides was "highly vulnerable" to deadly ozone pollution, also "unacceptable" pollution levels were found in Lutyen's Delhi and around hospitals.

The CSE has called on the Delhi government to implement daily health alert and pollution emergency action.

"The neighbourhoods of the rich and the powerful are highly vulnerable to deadly ozone pollution. The ozone level in Civil Lines, where Delhi chief minister Arvind Kejriwal resides, is more than twice the standards and falls in the 'poor' category of the National Air Quality Index (NAQI)," a CSE statement said.

CSE carried out the analysis of real time air quality data available from the key monitoring locations of Delhi Pollution Control Committee (DPCC) for the period April and May 2015.

"The high ozone level has made the cocktail of toxic pollutants deadly. Without a time-bound implementation strategy and preventive action, this can deepen into a serious public health crisis. It will spare neither the rich nor the poor," head of CSE's air pollution programme, Anumita Roychowdhury said.

The analysis found that Civil Lines area where Kejriwal stays was an "ozone hotspot" and had fared the worst in terms of number of days exceeding the standard for ozone.

The eight-hourly average of ozone here peaked to 250 microgram per cubic metre, which was 2.5 times more than the standard. In April, 92 per cent of the days exceeded the standard while in May it was as high as 97 per cent, CSE said.

CSE's own monitoring in Lodi Estate in Lutyens' Delhi as well as at All India Institute of Medical Sciences (AIIMS) has brought out the vulnerability of these areas.

During the day, the peak one-hourly averages frequently crossed the standards at Lodi Estate. Near AIIMS, the peak one-hour average has been recorded at 266 microgramme/cubic metre between 12 noon and 1pm, CSE said.

"The Delhi Pollution Control Board (DPCC) should carry out regular monitoring in sensitive areas as well as in Lutyens' Delhi. Lack of air pollution data in this area breeds complacency among the rich and the powerful," it said.

The CSE said while ozone levels have increased steadily with the onset of summer, it doubled up very quickly in most locations in Delhi as soon as the heat wave hit in the first week of May.

The analysis said on several occasions and locations, very high peak levels have been noted, close to 2.5 to three times the standards.

"This is of serious concern as even short duration exposure to high ozone levels can cause great harm. This is one of the reasons why ozone standards are set for an eight-hours average as well as a one-hour average," Roychowdhury said.

The analysis found that in R K Puram, the eight-hourly average reached the high point of 240 microgramme/cubic metre, almost 2.5 times higher than the safe standard of 100 microgramme/cubic metre.

It also found that in Punjabi Bagh, : In this area, the number of days violating the standards was very high. In April, 73 per cent of the days exceeded the standard; in May, this had gone up to 84 per cent. In May, the number of days with poor air quality was 30 per cent -- on 13.33 per cent of the days it was even worse than that.

CSE said that ozone is an extremely harmful gas and just a few hours of exposure to it can trigger serious health problems. It said that it can have immediate health impacts, especially among those who are already suffering from respiratory and asthmatic problems.

"Ozone worsens symptoms of asthma, leads to lung function impairment and damages lung tissues. Chest pain, coughing, nausea, headaches and chest congestion are common symptoms. It can even worsen heart disease, bronchitis and emphysema," CSE said.

The CSE urged the Delhi government to implement daily health alert and pollution emergency action and inform the sensitive population (children, elderly and those suffering from respiratory and cardiac problems) about the high daily levels and enforce emergency pollution control measures.

There was also a need for an urgent national action to leapfrog vehicle technology and fuel quality and control dieselisation and introduction of Bharat Stage IV nation-wide by the end of 2015 and leapfrog to Euro VI by 2020.

"There is a need for time bound implementation strategy to scale up public transport, walking and cycling to reduce vehicles usage and numbers. Reduce numbers of vehicles and traffic volumes. Implement source-wise action plan across the NCR region," CSE said.