THE scale of Farnham’s air pollution crisis has been laid bare, after an opposition councillor claimed new figures purport to show the town’s air quality is “by far the worse in Surrey” - producing higher mean levels of nitrogen dioxide (NO2) than even the M25.

A draft copy of Surrey County Council’s new ‘Low Emissions Strategy’ has revealed the annual mean concentration of nitrogen dioxide (NO2) in the Farnham Air Quality Management Area (AQMA) has risen to 50.4 micrograms per cubic meter of air (µg/m3), 26 per cent above the legal limit of 40 µg/m3.

This ranks Farnham the third worst AQMA in Surrey, behind only the M25 in Runnymead (53 µg/m3) and the A23 at Hooley (57 µg/m3). But Farnham Residents borough councillor Jerry Hyman believes as the data is based on “old figures”, the true picture is likely far worse - making Farnham the most polluted town in Surrey.

Waverley withdrew its 2016 annual air quality status report in August last year after the Farnham Society and Farnham-based air quality expert David Harvey raised concerns over its accuracy, and later referred the results of an independent audit of its air quality monitoring and reporting arrangements to Surrey Police, whose investigation is still ongoing.

The council has since published raw data from 19 diffusion tubes placed across Farnham online - revealing that levels of nitrogeon oxide in the Farnham AQMA were 61 per cent higher in November and December 2017 than Waverley claimed a year earlier.

Responding to the leaked figures, the councillor for Farnham Castle, Mr Hyman told The Herald: “The table shows Farnham air quality to be third worst in Surrey, based on old Waverley Borough Council figures - so Farnham would be worst with only a 15 per cent increase. “As the latest data suggests the true NO2 levels here are far higher, and it’s unlikely that a normal lab bias of a few per cent would affect that much, we might reasonably assume that the true figures for 2017 would have shown Farnham AQMA to be the worst in Surrey.”

Surrey’s strategy also reveals the Farnham AQMA affects 483 properties, roughly 10 times as many as the M25 and A23 Hooley AQMAs, and apportions the source of Farnham’s nitrogeon oxide emissions to 40 per cent ‘background’, 46 per cent ‘cars and LGVs’ and six per cent ‘HGVs’, adding the “level of reduction required will depend entirely on what types of vehicle are targeted”.

Levels of NO2, mostly produced by diesel vehicles, have been illegally high in Farnham since at least 2004, when an air quality management area was declared following the discovery of excessive levels of the toxic pollutant - particularly in The Borough. Since then, Waverley has been duty-bound to submit an annual report to the Department of Environment, Food and Rural Affairs (Defra).

A borough council spokesman said: “Waverley is still awaiting the outcome of the police investigation and will continue to support them with their enquiries.

“Since withdrawing the 2016 Air Quality Report due to concerns over its accuracy, the council has put a number of measures in place to ensure the accuracy of air quality monitoring in the borough.

“Accurate diffusion tube data is published on our website, but caution should be taken when looking at the figures as they are raw data, have not been adjusted in accordance with Defra guidance and therefore don’t provide a true picture of what is happening. “The council needs a full year of data to provide an accurate portrayal of the air quality levels across the borough.

“The council believes the Farnham figure of 50.4 g/m3, released in the report as part of the county council’s Low Emissions Transport Strategy consultation, is not representative of the whole Farnham AQMA but only of one location and therefore shows a worst case scenario. “We will question this figure in the report with the county council to be sure.

“Regardless, our residents’ health is extremely important to us and the council recognises more needs to be done to improve air quality levels in the Farnham AQMA.

“The council set up the Waverley Air Quality Steering Group and Farnham Air Quality Working Group to work with the county council, other relevant agencies, local councillors and community representatives to find solutions to help improve the issue.

“We believe highway infrastructure improvements and encouraging people to use more environmentally friendly forms of transport are the way to improve the air quality levels and the groups will be working on a revised action plan covering these themes over the coming months.”

It comes after new research, published last week, linked air pollution to changes in the structure of the heart of the sort seen in early stages of heart failure.

Nitrogeon oxide has long been linked to an increased risk of cancer, asthma, stroke and heart disease, diabetes, obesity, and changes linked to dementia. But according to researchers, exposure to NO2 and fine particulate matter, known as PM2.5 and PM10, can now be specifically linked to an increase in the size of two of the chambers of the heart, the left and right ventricle. Similar changes can affect the performance of the heart and are often seen before heart failure takes hold.

These findings could help to explain why areas with dirty air often record higher mortality rates. A Defra report in 2015 attributed 23,500 early deaths a year in the UK to nitrogeon oxide.