People in the national capital inhaled “very poor” air on Tuesday, a dangerous marker in the air quality standard that could make even healthy adults sick.
A strong breeze until noon kept the quantity of air pollution a little down, but the level of fine particulate matter or PM2.5 crossed the 300-microgram mark by evening as the wind eased and tens of thousands of people joined the Diwali shopping rush.
Exhaust fumes from cars crawling on clogged streets put the air quality back on the “very poor” side.
The forecast is more alarming because foul air will continue to engulf Delhi until Diwali, the festival of light when pollution levels exceed all parameters as revelers burst millions of firecrackers.
The city of about 20 million, which ranks among the world’s top cities with foul air on a WHO list, has been struggling to clean up its air that contains a toxic cocktail of dust, smoke and gases from vehicle and factory exhausts and coal-fired power stations.
The condition worsens every autumn and winter as the city, buffeted by farmers burning crop stalks in neighbouring states and atmospheric changes, records higher levels of air pollution.
“Rising pollution levels is a regular winter trend. Things will get worse around Diwali,” an environment department official said.
The System of Air Quality and Weather Forecasting and Research (SAFAR) recorded 353 microgram of PM2.5 for a cubic metre of air at its Pusa monitoring station. Other stations registered similar figures, way exceeding the safe upper limit of 60 microgram. PM2.5 dust can cause grave respiratory disorders.
But one of the city’s most polluted corners, Anand Vihar, showed PM2.5 levels at 60 micrograms, according to the Delhi Pollution Control Committee. The good part was blighted by PM10 levels at 658 micrograms, when the permissible limit is 100.
PM10 dust is a bit bigger than PM2.5, but equally dangerous. People were advised to avoid outdoor activity, especially the elderly and young children, and use anti-pollution masks, health experts said.