Data reveals air in every London borough breaches guidelines established by the World Health Organisation (WHO) as diffusion tubes placed across the capital detected excessive levels of nitrogen dioxide, a toxic pollutant.
An analysis by City Hall reveals that 100% of the 1,823 tubes that were tested had levels of nitrogen dioxide above the recommended limit of 10 µg/m3. Moreover, at least fourteen boroughs were found to have five or more localities which breached the legal limit of 40 µg/m3.
The Findings: London’s worse off areas
Data was gathered through the use of low-cost nitrogen dioxide diffusion tubes, which enabled the tracking of pollutant levels across a vast network of locations. These tubes were placed at roadside and background sites. All boroughs were part of the data collection, except for Bexley and Harrow, where air quality monitors were not installed by the councils.
The data pertains to the year 2021, during which Mayor Sadiq Khan extended the Ultra-low emission zone (Ulez) from central London to include the regions within the North and South Circular roads. The data indicates that there was a comparable average concentration of nitrogen dioxide in both inner and outer London, demonstrating the necessity of taking action throughout the entire city, according to City Hall.
Merton had the highest proportion of locations surveyed that surpassed the legal limit, with 27% exceeding it. This was trailed by Brent (26%) and Croydon (25%).
However, the number of sites examined within each borough varied significantly. Newham had 131 locations measured, while only 15 were measured in Barnet.
The highest concentration of nitrogen dioxide was recorded on Harlesden High Street in Brent, with an average measurement of 116.5 µg/m3, adjusted for bias. The second and third highest concentrations were recorded near Romford railway station (71.3 µg/m3) and the intersection of Wembley High Road with Ealing Road (64.5 µg/m3).
The Plan
Mayor of London, Sadiq Khan, is already planning to expand the Ulez boundary to cover the whole of Greater London in August.
The zone requires owners of older, more polluting vehicles to pay a daily charge of £12.50 to drive their cars. The Mayor said this new 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”.
Hirra Khan Adeogun, Head of Car Free Cities at the climate charity Possible, supports the expansion of the Ulez boundaries and believes that this will make streets “healthier and greener”. However, she added that there is much more work left to do – “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.”
However, this data has also led to the Conservatives vocalizing their opposition to Sadiq Khan’s plan to widen the Ulez boundary – 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”.
Final thought
The dangers of toxic air manifest as both health problems and environmental detriment. Tackling air pollution has become a priority for Sadiq Khan, expanding the Ulez boundary is just one plan he has set out for improving environmental standards.