The Mayor of London, Sadiq Khan, today hailed the success of his bold air quality policies which have led to the capital’s air pollution levels falling to within the legal limit for the first time.

In 2019, leading experts at Kings College London estimated that without additional action it would take 193 years for London to meet legal limits, but Sadiq has achieved this aim in just nine years – 184 years early.

New air quality data from Defra (Department for Environment, Food and Rural Affairs), published today, reveals that London met the Air Quality Standards regulations for the first time in 2024 (1). This is assessed through modelling and Defra’s approved air quality monitoring networks (2).

Sadiq has achieved this important milestone almost 200 years ahead of predictions, demonstrating the transformative impact of his bold policies to improve London’s air quality and protect Londoners’ health and the environment. Since he took office in 2016, following the implementation of his ambitious policies, such as ULEZ (Ultra Low Emission Zone), levels of toxic NO2 at roadsides has nearly halved (3).

In London, around 4,000 premature deaths per year were previously attributed to toxic air (4) and a recent report from the Royal College of Physicians estimates that air pollution costs the UK more than £27 billion per year (5). Air pollution increases the risk of developing asthma, lung cancer, heart disease and stroke, and there is growing evidence that air pollution exposure increases the risk of developing dementia (6). Reaching this milestone of achieving legal limits, years ahead of where we would have been without action, shows that bold policy can produce important benefits.

Despite huge pressure from many different quarters, from politicians to vested interests, the Mayor pressed on with expanding the ULEZ to all of London and it’s proven to be even more effective at cutting air pollution than previously predicted.