The World Health Organisation considers a safe daily level to be 25 microgrammes per cubic metre.

世界卫生组织规定，日安全值为每立方米25微克。

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Prosecutor Michael Smith said Mr Shaw, 37, was breathalysed at the scene and gave a reading of 83 microgrammes per 100 millilitres.

BBC: Leeds & West Yorkshire

However, a recent review of evidence carried out by WHO found there were now concerns about a health impact at levels much lower than 10 microgrammes per cubic metre.

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Xinhua says that readings in Beijing for the tiniest pollution particles - called PM2.5 - reached more than 400 microgrammes per cubic metre on Thursday, which is considered "dangerous".

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