According to latest findings the pollution levels of the city have surpassed the standard limits by two-fold. According to Mumbai Pollution Control Board(MPCB) logs, pollution levels particularly nitrogen oxide (NOx) and suspended particulate matter (SPM) have been exceptionally pernicious the past few days. Last week the SPM shot up to as high as 286 micrograms per cubic metre. NOx was recorded at 211 micrograms per cubic metre. "Anything above 100 micrograms of SPM and 80 micrograms of NOx in a cubic metre of air is bad for human health," said an MPCB official. Sounding a disquieting note, he added that in certain parts of the city pollution levels are perennially higher than the standard limits.
When the weather gets cooler, SPM levels do tend to rise because of inversion.
Normally, the air near earth's surface is warmer than that in the upper atmosphere. During inversion, however, there is cold air near the surface, which gets trapped under warmer air.
Experts say a dip in the mercury is not the only cause of Mumbai's poor air quality increasing vehicular density and construction pollution are equally to blame. "Pollution norms for vehicles may be in place, but their sheer numbers in Mumbai override those and lend to the addition in SPM levels," says Dr Pratibha Pawar, professor of physiology. "Vehicles emit more pollution when moving slow. In Mumbai, the problem gets amplified due to bumper-to-bumper traffic. Also, there is always some construction, renovation or restoration work happening, which is an even greater source of pollution," Dr Pawar continued.It must also be noted that the SPM and NOx readings were made at Bandra and Sion stations. Both these areas suffer major traffic issues. This is why pollution levels are high in these areas.
