Mumbai: After two days of satisfactory air, Mumbai’s air quality deteriorated sharply on Friday, with the city’s overall Air Quality Index (AQI) rising to 130 from 67 on Thursday and 70 on Wednesday — the steepest single-day spike recorded in the last three months. The reading pushed the city back into the moderate air category, undoing the brief mid-week gains. According to air quality standards, prolonged exposure at this level may cause breathing discomfort among sensitive groups.Within the city, Worli emerged as the most polluted locality at 278, slipping into the poor bracket. Bandra Kurla Complex followed at 160, while Kurla recorded 155. In contrast, Sion registered the cleanest air at 69, remaining in the satisfactory category. Byculla and Colaba recorded AQI levels of 79 each, and Mazgaon stood at 89, reflecting relatively better conditions than other pockets.The deterioration extended across the Mumbai Metropolitan Region. Navi Mumbai’s AQI rose to 112 from 88 on Wednesday and 93 on Thursday. Within Navi Mumbai, Sanpada was the most polluted at 129, while Kalamboli recorded the cleanest air at 77. Thane witnessed a pronounced spike, climbing to 132 after four consecutive days in the 80-90 range, thereby entering the moderate category. Despite wind speeds of 16.7 kmph — typically favourable for pollutant dispersion — air quality worsened across the region.Sunil Dahiya, founder and lead analyst at Enviroclysts, an environmental research organisation, said the pollution readings recorded on Friday were virtually double those seen on Wednesday and Thursday. “Across Wednesday, Thursday and Friday, wind speed and other meteorological conditions remained largely the same. What changed was the wind direction, with the early hours recording inland winds from the southeast, which are comparatively more polluted than winds from the west and north-west that originate from the sea,” he said, adding that another reason for particular pockets in the city is the “valley effect” created by clusters of skyscrapers which disrupts wind flow, preventing pollutants from dispersing and creating concentrated pockets of pollution in areas such as BKC and Worli, which routinely top AQI charts.
