” “If PM 2.5 levels touch 22.5 micrograms /cubic metre, breathing that air is considered equivalent to smoking one cigarette,” Arvind Kumar, chairman, Centre for Chest Surgery and Lung Transplantation at Sir Ganga Ram Hospital, New Delhi, said.
“Calculated thus, residents in polluted cities such as Delhi or Chennai are smoking an average of 8 to 10 cigarettes every day. Nearly half of my lung ailment patients in Delhi are now drawn from among non-smokers because of the high pollution levels in the city,” he said.”
The Hindu

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Pollution exceeds permissible limits: study