Bradford’s clean air zone has reduced air pollution and saved the health service about £30,700 a month in its first year, a study has found. Low emission or clean air zones are often controversial, especially when they are first proposed. The expansion of London’s ultra-low emission zone became a major election issue, spawning disinformation, protest, vandalism and even the bombing of a traffic camera. More than 300 low emission zones operate in the UK and Europe. There is substantial evidence that they can reduce air pollution from traffic, but fewer studies have examined if they actually improve health. Prof Rosie McEachan, the director of NHS Born in Bradford, who led the study, said: “There was a lot of scepticism. We wanted to evaluate if these types of policies improve health and the environment while providing value for money.” The Bradford zone covers 22.4 sq km, making it the second largest in England. From September 2022, older, more polluting lorries, buses and taxis have had to pay if they drove in the zone. McEachan said: “20% of the city population live inside the zone. These families tend to be the poorest, and most likely to suffer ill health. They are also less likely to cause pollution in the first place.” The researchers studied nearly 200,000 visits to GPs and to the emergency department at the Bradford Royal Infirmary. After one year of the zone, nitrogen dioxide from traffic was lower, GP visits for respiratory illnesses were down by 25% and those for heart problems decreased by 24%. This added up to an average of 732 fewer visits a month, compared with pre-Covid levels, and the trend showed that benefits were increasing over time. There were fewer patients with breathing problems at the Bradford Royal Infirmary emergency department, too, but no change was found for cardiovascular visits. The analysis was made more difficult by changes in traffic patterns during Covid restrictions. The researchers therefore had to use a period before lockdowns as their baseline. They also analysed trends, not just the number of cases, and looked at changes as vehicles were upgraded ahead of charging. Health benefits were found across the whole city, not just inside the zone. McEachan said: “I’m not surprised that we see a benefit across the whole city. The zone works by encouraging people to upgrade vehicles, which has benefits for wider areas, not just within the zone. For example, as a result of the clean air plan, Bradford has the cleanest taxi fleet in the UK.” Other studies in London and Germany found that cleaner vehicles used inside these zones were also driven in the surrounding area, spreading the benefit.