New Delhi: Delhiites could see poison in the air on Sunday. A thick layer of toxic smog enveloped the capital, turning the city into a gas chamber with air quality plunging to ‘severe-plus’ category for the first time this year.The city’s 24-hour average air quality index stood at 461, the second-worst recorded in Dec and the worst in nearly 13 months. Since the scale began in April 2015, only once has a higher AQI been recorded in Dec — 469 on Dec 21, 2017. For any month, the last time Delhiites a suffered worst AQI was on Nov 18 last year (494).High moisture, low temperatures and calm winds effectively trapped pollution close to the surface even as a grey smog screened out the sun for most of the day. Winds are predicted to pick up slightly post-noon on Monday, which could disperse some pollutants.

.