A new study of London’s air quality has revealed that the air in every borough breaches World Health Organization (WHO) guidelines on the toxic pollutant nitrogen dioxide.
Analysis by City Hall reveals that at 100 per cent of the 1,823 sites measured across the capital, nitrogen dioxide levels exceed the WHO’s recommended limit of 10 µg/m3.
Some 14 boroughs were also found to have five or more locations which breached the more stringent, legal limit of 40 µg/m3.
The borough with the highest percentage of places measured which breached that legal limit was Merton, with 27 per cent of sites exceeding it, followed by Brent (26 per cent) and Croydon (25 per cent) – though the number of places measured within each borough varied significantly. Just 15 sites were measured in Barnet, while 131 were measured in Newham.
The single highest concentration of nitrogen dioxide was found on Harlesden High Street, where 116.5 µg/m3 was measured on average, adjusted for bias.
NOW READ: Residents called to help borough become more resilient to climate change
It was followed by a site in Romford town centre, near the railway station (71.3 µg/m3) and by a location at the junction of Wembley High Road with Ealing Road (64.5 µg/m3).
The data was collected using nitrogen dioxide diffusion tubes – small, low-cost devices which enable the pollutant’s levels to be monitored over a wide network of locations. The tubes were placed both on roadsides and at “background” locations away from roads.
Every borough was included in the data collection – with the exceptions of Bexley and Harrow, where the boroughs’ councils did not install air quality monitors, City Hall said.
The data comes from 2021. In October of that year, Mayor Sadiq Khan expanded the Ultra low emission zone (Ulez) from central London to cover the area within the North and South Circular roads.
The data shows a similar average concentration of nitrogen dioxide in both inner and outer London – which City Hall said “showed the need to take action right across the city”.
Mr Khan is planning to expand the Ulez to cover the whole of Greater London on August 29. The zone requires owners of older, more polluting vehicles to pay a daily charge of £12.50 to drive their cars.
The Mayor said: “London’s toxic air is leading to children growing up with stunted lungs and causes around 4,000 premature deaths a year – with the greatest number of attributable deaths in London’s outer boroughs.”
He said the data “is yet more shocking proof that London’s air quality has been in serious breach of the recognised global standard – and it’s a problem in every single part of the capital”.
He added: “I have made tackling toxic air pollution a priority since I was first elected in 2016, and we have made huge progress since then. However, I am determined to do all I can to ensure that children now and the next generation of Londoners can grow up breathing cleaner air – wherever they live in the capital.
“This is why I made the difficult decision to expand the Ulez London-wide – to help save lives and to give all Londoners the right to breathe cleaner air.”
Hirra Khan Adeogun, Head of Car Free Cities at the climate charity Possible, said the data “shows just how much work there is still left to do on driving down air pollution and emissions in London”.
She added: “The Ulez expansion will certainly help by making our streets healthier and greener but we need to go further.
“Dedicated cycle lanes, road user charging, and investing in public transport, these are things that will help secure our climate and secure the long-term health of Londoners.”
A legal challenge to the Ulez expansion will be heard in the high court later this year, after a judgment permitted a group of five councils to proceed.
Four London borough councils – Hillingdon, Bexley, Bromley, Harrow – and Surrey county council were granted permission to challenge the policy earlier this month.
The five councils believe the plans are unlawful, arguing that there was a failure to follow statutory procedures and a failure to consider the potential for inclusion of non-Londoners in the new £110 million scrappage scheme.
The Mayor’s office said the expansion plans would continue “without delay”.
City Hall Conservatives said that the London-wide Ulez would have a “disastrous” impact on people’s finances.
Tony Devenish AM, City Hall Conservatives environment spokesperson, said: “The science is clear: Sadiq Khan’s Ulez expansion would have a negligible effect on air quality, while having a devastating impact on low income families, businesses and charities.
“Sadiq Khan should scrap this disastrous plan and start tackling air pollution where it is, instead of taxing people where it isn’t.”
For the latest headlines from the City of London and beyond, follow City Matters on Twitter, Instagram and LinkedIn.