London smog
London has already breached its annual pollution limit in just one week into 2016Reuters

Former London mayor, Boris Johnson, has been accused of burying an air quality report during his tenure, which revealed that hundreds of schools were in areas that surpassed the EU's air pollution limits. According to the leaked report titled, Analysing Air Pollution Exposure in London, around 433 out of 1,777 primary schools were located in areas that exceeded EU limits for nitrogen dioxide pollution, out of which 83% were deprived schools.

Although the report was completed in 2013 it was allegedly not released under Johnson's tenure. However, a spokeswoman for Mayor Sadiq Khan said, "This shocking report reveals a snapshot of the true ‎impact that our polluted air has on some of London's most vulnerable communities.

"It is difficult to understand why the last mayoralty decided to cover it up and not fully release it in 2013 – they clearly didn't want Londoners to know the dire state of pollution in the capital."

"The mayor is fully committed to cleaning up our air and protecting Londoners' health and is shocked to learn that important scientific evidence like this have been locked and ignored at City Hall," she added.

Khan plans to make the report public and pursue the issue of air pollution levels in the city. The research was commissioned by Aether, an independent consultancy that examined air pollution data from 2010. However, the researchers did mention that the affected schools would reduce by 2020, as air improvement measures took effect.

The report was authored by Katie King and Sean Healy and was commissioned by the Greater London Authority (GLA). The report also claimed that London has constantly breached EU limits since 2010, but is expected to meet the standards by 2025.