As parents walk with their children next to four lanes of fume-belching traffic in Kingston, Oliver Lord sighs. “We shouldn’t be setting a carer with a car against a mum looking after her son with asthma in hospital,” says Lord, who is head of strategy for the Clean Cities campaign. He and other campaigners are dismayed at how clean air has become a political battleground, with tensions rising over plans to extend an ultra-low emission zone (Ulez) to cover the whole of Greater London. Last week, Sadiq Khan, the mayor of London, was confronted by protesters carrying a sign depicting him with a swastika and a hammer and sickle at a public meeting in Ealing, west London. Khan himself did little to calm matters, claiming that people with legitimate objections to the Ulez expansion had been “joining hands” with the far right. “Some of those outside are part of the far right,” he said. “Some are Covid deniers. Some are vaccine deniers and some are Tories.” The unlikely coalition of London Ulez opponents ranges from Jacob Rees-Mogg, the MP for North East Somerset, and Conservative-controlled councils in and around London to anti-vaccination activists including Richard Fairbrass of Right Said Fred and Piers Corbyn. But it includes plenty of ordinary people too, from builders and sales managers to chefs and carers. Consumer finance expert Martin Lewis, speaking alongside Khan at an event on the cost of living last month, also raised concerns. “The reasons behind [expanding Ulez] are good, but the timing is pretty tough to do it this year in a cost of living crisis.” The Ulez was Boris Johnson’s plan, originally confined to the city centre, but expanded in 2021 by Khan to cover inner London. Drivers of the most polluting cars and vans must pay £12.50 a day or face a fine, while HGVs and buses pay £100. Since then, the majority of the most polluting vehicles have gone from inner London and emissions of nitrogen dioxide (NO2) are 26% lower. City Hall points out that only 6% of vehicles pay the charge. The mayor intends to expand the zone on 29 August and has launched a £110m scrappage scheme with up to £2,000 compensation for low-income drivers and up to £9,500 for van-driving small businesses and charities. Yet that will not be enough to help tradespeople and key workers. Perhaps seeing an opportunity to make life awkward for a political opponent, the Conservative government has rejected the Labour mayor’s request to top up the scrappage fund, despite giving similar amounts for schemes in Manchester as well as in Bradford and Birmingham. Surrey county council has allied with other Tory-controlled outer London boroughs – Bexley, Bromley, Harrow and Hillingdon – to launch a legal challenge to the extension. If the Ulez extension is stymied, it would leave residents of places like Kingston-upon-Thames still breathing some of the most toxic air in the capital. Depending on the weather, roads in outer London have “a lot more pollution than we may see in inner London, just simply because the vehicles are cleaner”, according to Prof Frank Kelly, head of Imperial College’s Environmental Research Group. Standing next to one of the roadside air pollution monitors that measures pollution along Cromwell Road in Kingston, Oliver Lord points to rows of flats and a school next to three lanes of traffic. “This has been showing illegal levels of nitrogen dioxide for 12 years, even though they were meant to end in 2010,” he says. “A whole generation of kids has grown up in Kingston with harmful levels of air pollution.” This particular air pollution monitor – a curious combination of tubes, funnels and vents on a box at the side of the Cromwell Road – shows an annual average of 43 micrograms per cubic metre – four times the guideline set by the World Health Organization. Jonathan Hudson, a cardiology registrar at Kingston hospital, said people wrongly assumed that air pollution mainly created lung problems. “Air pollution is a risk factor for heart disease,” he said. “People can think they’re living very healthy lives, eating a good diet and doing exercise. But if you’re on a cycle ride down the Cromwell Road, you’re inhaling fumes that have a very detrimental effect on your heart.” Rosamund Adoo-Kissi-Debrah has campaigned for clean air for the last 10 years since the death of her daughter Ella at the age of nine. She had asthma, and her mother had to perform CPR to resuscitate her “time after time”, she told the Observer. When Ella died, a coroner ruled she had been a victim of air pollution, and the government pledged to act. “And they haven’t done what they’re meant to do,” she says. “How much have they contributed to the scrappage scheme? Zero. Londoners pay huge amounts in excise duty. Where’s our money? Don’t be playing games with Londoners. “Poor people are being used. People on universal credit aren’t driving cars – they’re waiting at bus stops in the fumes.” Adoo-Kissi-Debrah said ministers should “listen to Chris Whitty”, after England’s chief medical officer said indoor spaces should be monitored for air quality. Although Surrey county council is part of the lawsuit trying to stop the Ulez, the council’s cabinet member for transport, Matt Furniss, says the council agreed with the principle. “Our concerns are about the significant financial and social impact on Surrey residents and businesses who need to cross the boundary every day,” he says. The council wants the mayor to extend the scrappage scheme to some of estimated 160,000 cars in Surrey which are not Ulez compliant, extend public transport into the county, exempt key workers from the charge and fund better bus routes in Surrey. “That’s why we’ve launched the legal action to get the Mayor of London and TfL to engage with us,” he adds. Khan, though, is pressing on. “If it’s good enough for those in central London, why isn’t it good enough for those in outer London?” he told the meeting in Ealing. “Clean Air is a human right, not a privilege.”