Schools closed this morning in Beijing, China, after government officials were forced to issue the city’s first ever “red alert” for pollution.  

Classes were cancelled and residents were advised to stay indoors as the air quality in the capital had reached hazardous levels.

The warning meant that about a third of the city’s cars were ordered off the road and construction sites were shut down in a bid to improve the air quality.

Beijing’s Municipal Bureau of Environmental Protection said that the pollution would cloak the Chinese capital for several days.

According to reports, the air quality index showed that smog particles had reached more than 250 micrograms per cubic metre, a level deemed “very unhealthy” and 10 times the World Health Organisation’s maximum safe level.

The problem of air pollution affecting schools is not limited to China, however. Just last week, research by Policy Exchange and King’s College London showed that nearly one in four schoolchildren were breathing air deemed to be unsafe by EU standards.

The toxic level of pollution can lead to asthma, poor lung development and other respiratory problems.

The issue is a particular cause for concern for schools and parents because children’s lungs are less developed and more susceptible to damage caused by pollution.

Richard Howard, author of the report, said: “The case for tackling air pollution in London is clear. London’s air is unhealthy to breathe. Children are particularly vulnerable to unsafe levels of air pollution.”

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