The resultant haze also traps other pollutants, which has led to an overall rise in pollution in Delhi, as per the latest Central Pollution Control Board (CPCB) findings. Further, traditionally less-polluted residential areas are registering an increase in pollutants.

In 2007, Delhi had RSPM levels of 159 miligrams per metre cube in residential areas. In the 2007 list, the second most polluted cities were Ludhiana (Punjab) and Khurja (UP) with RSPM at 201 mg/metre cube. Delhi was at number 13 on the list.

By 2008, the RSPM in residential areas in Delhi shot up to 200 mg/metre cube, which is comparable with some of the most polluted cities in India. This is much higher than the ‘safe’ standard for residential areas: 60 mg per metre cube.

“RSPM is a dangerous pollutant. It consists of respirable particles which are below 10 microns in size. In Delhi, RSPM levels have gone up due to numerous construction activities and vehicular pollution,” says S D Makhijani, Director, CPCB. “RSPM is also caused by natural dust. However, the smaller the particle, the more dangerous it is for human health,” he says. RSPM gets injested in the trachea and is known to trigger asthma attacks and affect the heart and lungs. Haze in residential areas is considered a larger danger to public health (as opposed to industrial areas). Respiratory problems in children are on the rise due to an increase in pollution.

Other pollutants like Nitrogen Oxide and Suspended Particulate Matter (particles larger than 10 microns) have also gone up in 2008 in the residential areas surveyed: Pitampura, Sirifort, Janakpuri and Nizamuddin. SPM, which also contributes to the haze and difficulty in breathing, is at an average of above 400 mg/ metre cube, while in 2007 it was around 350 mg/metre cube.

Surprisingly, pollutions levels in one of the most polluted areas in Delhi, the Bahadur Shah Zafar Marg, have gone down slightly. RSPM levels remained same at 211 miligram per metre cube, but SPM has gone down from 464 to 450 mg/metre cube. Carbon Monoxide, caused by incomplete vehicular combustion, has gone down here from 2463 to 2249 mg/metre cube, which the CPCB attributes to better car engines and traffic management.