Chinese authorities remove pollution documentary "Under the Dome" from online video sites

Environmental expose "Under the Dome" garnered hundreds of millions of views within days of its release but was removed on Saturday

Pollution in China is consistently among the worst in the world (Getty Images)

Chinese authorities have taken the damning pollution documentary “Under the Dome” offline after it gained hundreds of millions of views within days of its release.

The 103-minute documentary by Chinese journalist Chai Jing explores the social and health costs of pollution in the country following a year-long investigation.

She speaks plainly to an audience throughout the video, in a style reminiscent of Al Gore’s “An Inconvenient Truth”.

As one of the first in-depth studies of the extent of China’s pollution problems, it is viewed by many as a potential watershed moment that could spark national debate and change.

As well as including basic facts and figures about pollution, the film also examines the effects of smog and lax industrial practices outside of Beijing in lesser-reported provinces.

She shows villagers in Shaanxi province, whose health was put severely at risk by dangerous pollutants from nearby coal plants, including a six-year-old girl who tells her she has never seen stars or blue sky.

Chinese air pollution can create heavy smogs such as this one in Lianyungang (Getty Images)

Self-funded by Chai, an investigative journalist, the documentary also gains unprecedented access to factories where she manages to document regulations being broken on camera and she sharply criticises the Chinese government’s lax environmental laws.

As of Saturday, the film had been removed from popular Chinese mainland video sites such as Youku.

Neither Youku nor Ms Chai responded immediately when asked to comment, the Reuters news agency reported.

In 2010 outdoor air pollution contributed to 1.2 million premature deaths in China, the 2010 Global Burden of Disease Study found. Curbing pollution, particularly from coal-burning factories, remains a daunting challenge for the country.