Increased traffic from low traffic neighbourhoods has led to safe air pollution levels being breached in parts of Oxford, new figures have revealed. 

An Oxford City Council report released on Thursday morning showed unsafe levels in six city locations, with St Clement’s near The Plain – adjacent to East Oxford LTNs – being the worst affected for abnormal levels of nitrogen dioxide. 

Nitrogen dioxide is directly associated with conditions such as asthma and chronic lung disease. 

The council has released new official data for 2022 which has shown that overall nitrogen dioxide levels decreased by 8.3 per cent on average in the city and a 22 per cent reduction in air pollution took place when compared with pre-pandemic levels.

Oxford Mail: Maggie Brown, an Oxford resident who suffers with asthma holding her inhaler Maggie Brown, an Oxford resident who suffers with asthma holding her inhaler (Image: Ed Halford)

However, the council’s data revealed that St Clement’s Street and The Plain saw a 10 per cent increase in 2022, resulting in the area breaching the UK’s annual legal limit.

READ MORE: Oxford LTNs and pollution: 'Suffering' residents feel 'trapped'

The report said this data indicates the street has “seen the impacts of LTNs” through traffic displacement.

LTNs were introduced with the aim of reducing through traffic and encouraging more people to make local journeys by cycling or on foot.

Average nitrogen dioxide levels for the year were exceeded at five other locations within the city according to the new data.

These were the Northern Bypass/Horspath Industrial Estate, Brasenose Farm/ Eastern Bypass, Headington Hill/Headington Road, the Southern Bypass Road and Wolvercote Meadows.

These findings come after the Oxford Mail released a special report on pollution in the city, in which residents said pollution had become “really bad” and stationary traffic was clogging up roads since LTNs were installed.

The council has highlighted that St Clement’s is the only location that is within an area of high public exposure.

READ MORE: Councillors 'silenced' over Oxford United stadium move

The report has further uncovered that major roads near LTNs have been seeing the impact of traffic displacement through rises in nitrogen dioxide levels.

The monitoring site on Cowley Road, where it crosses with James Street, recorded an increase of 35 per cent in nitrogen dioxide levels.


Oxford Mail: Sign up to Ed Halford's free weekly Politics newsletter here Sign up to Ed Halford's free weekly Politics newsletter here (Image: Newsquest)

The report explictly stated this increase was “most likely the result of this being the only road that moves across the three LTNs” so vehicles have been diverting from the surrounding LTNs.

No significant changes in NO2 levels were seen on Hollow Way Road, Oxford Road/Between Town Road or Oxford Road/Cowley Police Station.

All the areas monitored within the East Oxford LTNs showed a decrease in NO2, with Divinity Road and Prince Street seeing a 33 and 24 per cent reduction in pollution levels respectively.

Within the St Marys neighbourhood LTN, both Howard Street and Hurst Street saw a 19 per cent reduction in NO2 levels.

Roads within the Zero Emission Zone pilot area also saw decreases in nitrogen dioxide levels, with a 14 and 18 per cent reduction taking place on Cornmarket Street and St Michael's Street.

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Despite the breaches to legal limits in six locations, senior council officials welcomed the overall reduction of pollution levels in the city.

County council cabinet member for travel, Duncan Enright, said: “We are pleased to see Oxford City Council’s latest air quality annual report and its timely publication on Clean Air Day - especially as it shows improvement in air quality across the city.

Oxford Mail: Councillor Duncan Enright Councillor Duncan Enright

“The new electric bus fleet will take us even further towards the healthy streets we want to see.”

City councillor and cabinet member for zero carbon Oxford, Anna Railton, said: “Our latest data has found that during 2022, air pollution levels reduced overall across the city, not only compared to 2021 data, but also compared to pre-pandemic levels- and despite an increase in traffic levels.”

The full report ‘Air Quality Annual Status Report 2022’ can be found on Oxford City Council’s website.

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Ed specialises in writing political stories for the Oxford Mail and The Oxford Times. 

He joined in the team in February 2023, after completing a History undergraduate degree at the University of York and studying for his NCTJ diploma in London.

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