Delhi ranks sixth among India’s most polluted cities. This Haryana city tops October list

DElhi ranked as the 6th to the highest degree polluted metropolis in the rural area in oct, behind Ghaziabad and Noida, according to a new study.Dharuhera in Rewari district of Haryana emerged as the most polluted city, recording a monthly average PM2.5 concentration of 123 µg/m³, the Monthly Air Quality Snapshot released by the Centre for Research on Energy and Clean Air (CREA) on Tuesday showed.The snapshot is based on continuous ambient air quality monitoring station (CAAQMS) data and offers a comprehensive overview of India’s air quality.Also Read | Delhi AQI stays 'very poor', likely to worsen this week: What's behind the air quality drop?What did the findings reveal?The findings showed a sharp decline in air quality nationwide, with the Indo-Gangetic Plain (IGP), especially the National Capital Region (NCR) experiencing the most severe deterioration, according to an official statement.Delhi recorded an average PM2.5 concentration of 107 µg/m³ in October, three times higher than its September average of 36 µg/m³.Despite stubble burning contributing “less than 6 per cent” to Delhi’s PM2.5 levels in October, the steep rise shows the impact of year-round emissions and the need for long-term solutions beyond short seasonal actions such as the Graded Response Action Plan (GRAP), the study noted.Also Read | 2 years since Delhi saw ‘good’ air: Alarming data amid pollution woesDharuhera, Rohtak, Ghaziabad and Noida: Top 4Dharuhera, which topped the list, exceeded the National Ambient Air Quality Standard (NAAQS) limit on 77% of the days in October. It also saw two ‘Severe’ days and nine ‘Very Poor’ days.After Dharuhera, the most polluted cities were Rohtak, Ghaziabad, Noida, Ballabgarh, Delhi, Bhiwadi, Greater Noida, Hapur and Gurgaon. Four cities each from Uttar Pradesh and Haryana featured in the top 10, all within the NCR.Which were the cleanest cities?At the other end of the spectrum, Shillong in Meghalaya was the cleanest city in October, with an average PM2.5 concentration of 10 µg/m³.The top 10 cleanest cities included four from Karnataka, three from Tamil Nadu, and one each from Meghalaya, Sikkim and Chhattisgarh.Out of 249 cities, 212 recorded PM2.5 levels below India’s NAAQS of 60 µg/m³. However, only six cities met the World Health Organization’s (WHO) daily safe guideline of 15 µg/m³.Air quality classifications also shifted sharply in October: cities in the ‘Good’ category (0–30 µg/m³) fell from 179 in September to 68, while those in the ‘Satisfactory’ range (31–60 µg/m³) rose from 52 to 144.Cities in the ‘Moderate’ bracket (61–90 µg/m³) increased from 4 to 27, nine cities moved into the ‘Poor’ category (91–120 µg/m³), and one city entered the ‘Very Poor’ range (121–250 µg/m³).