Patna was the second most polluted city in India on Sunday, recording an air quality index (AQI) of 316, which is classified as 'very poor'.
Other cities in the state that recorded 'poor' AQI are Siwan (282), Muzaffarpur (233), Hajipur (232) and Bettiah (221).
Greater Noida in UP was the most polluted city in the country with an AQI of 346, according to the Central Pollution Control Board (CPCB) bulletin at 4 pm.
'Very poor' air quality causes respiratory illness on prolonged exposure, according to the CPCB.
AQI is an assessment of air quality that takes into account pollutants, including PM 2.5 -- particulate matter less than 2.5 microns, and PM 10.
Bihar State Pollution Control Board (BSPCB) chairman Devendra Kumar Shukla told PTI, "It is true that the air quality has deteriorated in certain cities of the state. It is because of low wind speed, ongoing construction activities without following pollution control measures and recent fire incidents in Patna and surrounding areas." He said civic bodies will have to start sprinkling water to check the deteriorating AQI in the state capital.
"Rain will certainly bring some immediate relief. The BSPCB will soon intensify its drive to check deteriorating AQI levels in certain cities of the state," he added.
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