mumbai

Updated: Jun 05, 2019 08:27 IST

Emission from industries, power plants and biofuel emission and open burning in the city accounted for 63% of particulate matter (PM) 2.5 sources in the Mumbai Metropolitan Region (MMR) in 2018.

Ahead of this year’s World Environment Day (June 5), data released by the System of Air Quality Weather Forecasting and Research (SAFAR) under the Indian Institute of Tropical Meteorology (IITM), Union earth sciences ministry, calculated source apportionment for PM 2.5 pollutant and PM10 in 2018 (see box).

“Air pollution sources in cities like Delhi and Pune are mainly from vehicular emissions. However, in Mumbai, the main problem is slum areas that use biofuel (black carbon for cooking) or burn waste openly,” said Gufran Beig, project director, SAFAR. “Combined with this, emission from industries was responsible for almost two-thirds of PM2.5 share in Mumbai’s air last year.”

According to the state, Mumbai’s slums occupy 12% of its geographical area while industries are spread across a little over 3%. “If the Centre’s policy of providing liquefied petroleum gas (LPG) to below poverty line families under the Pradhan Mantri Ujjwala Yojana (PMUY) is implemented properly across slum areas, it will help reduce a large proportion of particulate pollution. Secondly, stricter emission norms are needed for industrial emissions and for thermal power plants across MMR.”

SAFAR also released annual and seasonal data for PM10, PM2.5, and PM1 (smallest and deadliest PM) that witnessed an overall increase from 2017 to 2018. The PM levels were much above safe limits during all seasons except monsoon. Even the annual average of PM levels was above the safe limit. (see box)

The share of PM1 in winter in Mumbai in 2017 and 2018 was as high as 43 and 44 microgrammes per cubic metre, which was at par with levels in Delhi, and much above levels in Pune and Ahmedabad, said Beig. “PM1 is an ultrafine invisible killer pollutant. The share of PM1 in PM2.5 mainly comes from vehicular emission and fossil fuel burning. It is extremely hazardous for our respiratory system,” he said.

While SAFAR suggested recommendations to improve air quality, the Maharashtra Pollution Control Board (MPCB) said that MMR’s five-year air pollution action will tackle every emission source raised by SAFAR (see interview). “The situation in Mumbai is still under control as the city has a distinct advantage of sea breeze throughout disperses pollutants generated from man-made sources,” said Beig.

Owing to air pollution, city-based doctors said children were at twice the risk of adults to develop chronic obstructive pulmonary disease, bronchitis; hypersensitivity pneumonitis and asthma during post-monsoon and winter months. “Research suggests that continuous exposure to noxious particles weakens children’s lungs,” said Dr Sanjeev Mehta, pulmonologist, department of chest medicine, Lilavati Hospital in Bandra.

Independent researchers said a multisector time-bound clean air action plan needs to be executed.

“The power sector has to adopt new standards notified by the Centre this year. The PMUY scheme can address the major biofuel emission concern, but it needs to be leveraged so that it actually reaches every nook and corner of the city,” said Anumita Roy Choudhury, executive director, Centre for Science and Environment, Delhi.