A claim that Newcastle is the second most polluted city in all of Europe has been labelled “completely unreliable and misleading” by furious city leaders.

Research published by air quality monitoring business Airly on Thursday put Newcastle behind only the Romanian city of Cluj for the concentration of dangerous nitrogen dioxide (NO2) in its air.

But the ranking, released on Clean Air Day, sparked anger among Newcastle City Council chiefs, who claim that the data “does not provide an accurate representation”.

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Civic centre officials complained that Airly appeared to have used average pollution figures from only four locations in the city.

While Airly’s analysis on the severity of the problem has been angrily denied, city council bosses have been grappling with a pollution crisis over recent years – with poor air quality linked to more than 300 deaths on Tyneside annually.

Clean Air Zone tolls of up to £50 a day for some high-polluting vehicles are due to come into force later this year, after a government order to bring down illegal emissions levels.

Among the other green initiatives planned for Newcastle is the pedestrianisation of much of the city centre, including the Blackett Street bus route and the iconic Grey Street, while next week could also see plans approved for a rollout of more ‘Low Traffic Neighbourhoods’ across Newcastle.

General view of the morning traffic traveling into Newcastle City Centre on the Redheugh Bridge.

A spokesperson for Newcastle City Council said: “The so-called league table published by Airly today is completely unreliable and misleading.

“Despite Newcastle having hundreds of validated air quality monitoring devices, it would appear they have taken average figures from only four monitoring locations, including one at a tunnel, over a very short period of time and have only looked at certain cities.

“This does not provide an accurate representation or appropriate comparison of levels of air pollution across cities in Europe.

“Like many cities, Newcastle is acting to address air pollution. Reducing traffic levels in residential areas and outside of schools, creating better-connected walking and cycling routes and improving public transport networks are just some of the actions that we are putting in place.

“We’re also taking action in our city centre, with a Clean Air Zone (CAZ) due to be introduced and additional plans to remove motor vehicles from key areas.

“Air pollution has very serious health implications for us all and we are committed to addressing this through the powers at our disposal. It’s hugely disappointing that oversimplified and generalised analysis detracts from the important issue of raising awareness and demonstrating to people the reality of the situation and the need for us all to do our bit.”

Airly’s index of NO2 concentration gave Newcastle a score of 17.05 in the European Common Air Quality Index (CAQI), the second highest behind Cluj’s 17.53.

Leeds, Edinburgh, London, Dundee, and Slough were the other UK locations named in the top 20 cities most polluted with NO2 as of May 2021.

The pollutant is released through the burning of fossil fuels, including to power vehicles, and can have a range of harmful effects on the lungs.

Airly CEO and co-founder Wiktor Warchałowski commented: “With 62% of the world’s governments sharing no real-time air quality, we wanted to take this initiative and show everyone what’s happening in the air around us on Clean Air Day.

“The data isn’t great for large parts of Europe but there is certainly an opportunity to tackle the problem.

General view of the morning traffic traveling into Newcastle City Centre on the Tyne Bridge

“People need to change their habits especially with the use of cars and local authorities need to start by monitoring the problem then put in place appropriate policies to manage problem hotspots”.

Airly also produced analysis of the 20 cities with the highest concentration of PM10 particulate matter, none of which were in the UK.

Tay Pitman, of the Newcastle Green Party, claimed that Newcastle leaders "haven’t taken advantage" of chances to cut pollution in the city.

She said: "The pandemic has shown us that by reducing the number of short car journeys into the city, air quality improves.

"We’ve had an ideal opportunity to implement a bolder version of the CAZ, reduce residential speed limits, create Low Traffic Neighbourhoods and more, safe cycle routes, yet the City Council haven’t taken advantage of this.

"They announced the CAZ late in 2019 and they’ve been stalling on implementing it ever since.

"Air pollution killed 317 people in Newcastle in 2017. Air pollution affects everyone and it’s vital that the city council puts the health of our people and planet first by finding the courage to implement measures to reduce private car journeys."