In one of the more poignant scenes from Under the Dome — a documentary about China’s environmental catastrophe that has descended on the national consciousness like a thick smog — a six-year-old girl living in the coal mining province of Shanxi is asked if she has ever seen the stars. The child of China’s economic miracle says she has not. Chai Jing, who made the documentary, describes how she often keeps her own daughter at home “like a prisoner” to protect her from the noxious particles swirling outside.

“One morning I saw my daughter banging on the window,” she says. “The day will come when she asks me, ‘Why do you keep me here?’” The answer to that question, as Chinese people are ever more aware, is that there has been a high price to pay for the country’s admittedly startling economic development. The Lancet estimated that air pollution contributed to the premature deaths of 1.2m people in 2010, 40 per cent of the global total.

Air pollution is not the half of it. Soil is poisoned, rivers are choked with effluence (or diseased animal carcases), fauna and flora are disappearing. The World Bank has estimated that, in 2009, the cost of air pollution alone in terms of disease, premature death and lost income was 3.3 per cent of gross domestic product. If you took the figure literally, China’s “real” growth rate this year would fall below 4 per cent.