Delhiites woke up to grey skies on Monday as air pollution reached the severe category again after a few days of relatively cleaner air last week.
The Air Quality Index (AQI) for Delhi was recorded at 426 at 4 p.m. by the Central Pollution Control Board (CBCB), up from 171, which was ‘moderate’, on Sunday. Levels of particulate matter shot up to around four times the standards.
According to the System of Air Quality and Weather Forecasting and Research (SAFAR) index, the 24-hour rolling average level of PM10 at 9 p.m. was 412 micrograms per cubic metre (ug/m3), over four times the standard of 100 ug/m3. Similarly, the level of fine particulate matter PM2.5 was recorded at 299 ug/m3, almost five times the standard of 60 ug/m3.
In a statement, SAFAR said there had been a “significant intrusion of biomass [stubble] generated pollution” on Monday.
However, the air quality was forecast to go down to ‘very poor’ on Tuesday, a day before Diwali.
Meanwhile, environmentalists stressed the need to reduce emissions, particularly vehicular pollution. Anumita Roychowdhury, executive director of the Centre for Science and Environment, said while other sources of pollution — power plants, construction etc. — had been curbed, vehicles had not been touched.
Bursting crackers
With firecrackers on Diwali expected to increase pollution this week, doctors braced for the potential rush of patients. Recent studies have indicated that exposure to particulate air pollution also may be associated with acute heart attack.
“We are gearing up for increased patient flow during Diwali and are currently dealing with patients who are coming in with the adverse effect of high air pollution,” said Anil Bansal from the Delhi Medical Association.
He added that short-term particulate exposure contributed to acute coronary events in patients with underlying coronary artery disease. PM1, PM2.5 and PM10 are risk factors of all-cause, cardiovascular, stroke, respiratory, and COPD mortality. PM1 accounts for the vast majority of short-term PM2.5- and PM10-induced mortality.
Smaller size fractions of PM have a more toxic mortality impact.
Studies have shown that there is increasing evidence for the role of environment in pathogenesis in many diseases.
Those at risk
Children below five years of age and adults older than 50 years are most at risk.
A global assessment of the burden of disease from environmental risks by the WHO has shown that 23% of global deaths and 26% of deaths among children under five are due to modifiable environmental factors.
“The air quality is particularly poor in the early morning when pollution is extremely high. This is also the time when many people venture out to exercise or drop their school children. It is imperative to use a mask and also make people aware of the harmful effects of air pollution,” said K.K. Aggarwal, the former president Indian Medical Association.
Post-Diwali
Delhi’s air quality is expected to deteriorate to ‘severe plus emergency’ category after Diwali, stated SAFAR.
Air quality will be “bad” on November 8 even if “partial toxic crackers” are burned compared to last year, said the agency.
(With PTI inputs)