Air quality in New Delhi deteriorated alarmingly a day after Diwali as pollution levels spiked more than five times higher than normal leaving many at the risk of respiratory problems.

The Respirable Suspended Particulate Matter, which directly affects breathing, has gone up by five times from the national ambiance air quality standard, stated scientists from System of Air quality and Weather Forecasting and Research.

"The 24-hours average of PM10 was recorded at 427 mg per cubic metre and PM2.5 was at 278 mpcm, almost five times higher than the prescribed standard of 100 mpcm and 60 mpcm respectively," said senior scientist Dr Gufran Beig at SAFAR, which is jointly run by the Indian Institute of Tropical Meteorology and India Meteorological Department.

"These pollutants can harm the heart and brain as well. People with existing heart or lung diseases such as asthma, chronic obstructive pulmonary disease, congestive heart disease, or ischemic heart disease are at increased risk of admission to hospitals based on the severity of already existing problem," he said.