London has breached annual air pollution limits within a week for the third successive year.
Brixton Road, Lambeth took just five days of 2017 to register levels of pollutant nitrogen exceeding annual limits, making it the first air quality monitoring site to do so this year.
Putney High Street breached regulations by January 8 in 2016. In 2015 Oxford Street surpassed the annual limit in two days.
Under EU rules, sites are only allowed to exceed hourly limits on concentrations of nitrogen dioxide (NO₂) 18 times a year. NO₂ is a toxic gas produced by diesel vehicles that is linked to respiratory and heart problems.