Indian people relax on the lawns near smog enveloped government offices on Rajpath in New Delhi on December 2, 2015.
December 24, 2015 12:12 AM EST

India’s capital New Delhi, already widely considered the world’s worst-polluted city, hit a new low this week when it recorded its most polluted day of the year on Wednesday.

Pollution levels across the city were placed in the government’s highest “severe” category, reports the Press Trust of India (PTI) news agency.

Delhi’s citizens encountered exceedingly high levels of PM 2.5 and PM 10 — two types of particles known to be harmful to human health — with the former reaching 295 micrograms per cubic meter and the latter going up to 470. Acceptable upper limits for the two pollutants have been set at 60 and 100 micrograms per cubic meter respectively.

The pollution even exceeded the levels seen in late November during the Indian festival of Diwali, commonly celebrated by bursting firecrackers.

Although the cause of the dip in air quality is not conclusively known, experts told PTI that it was likely caused by the burning of dry leaves for warmth during the biting winter faced by most of northern India.


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