How bad is Delhi's air? We strapped a monitor to a rickshaw to find out

Suresh Kumar Sharma is an auto-rickshaw driver in Delhi, a city with some of the world’s dirtiest air – and where many locals don’t know how unhealthy it is. We monitored the dangerous PM2.5 particles surrounding Suresh’s rickshaw for 12 hours, then had his lungs tested: ‘I was shocked’

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