Nomadlozi Dladla wakes up most mornings in her hometown of Kriel in Mpumalanga, in wonder that she is still alive.

She is caught between a rock and a hard place. “This place is so polluted but due to work prospects we cannot relocate to any other place. At least here we have jobs,” she explains.

The mining town has earned itself the dubious honour of being rated the world’s second-largest hot spot for sulphur dioxide emissions, according to a Greenpeace India report, based on Nasa satellites tracking SO2 hot spots around the world...