Air pollution measures are to be reassessed in one of Kent's most polluted towns ahead of a decision over whether to scrap certain monitoring sites.

Dartford council continues to plot a path towards improving the air its residents breathe as it draws up a new air quality action plan.

Assessment of the latest 2019 data from roadside monitoring sites painted a cleaner image of the borough after it was revealed nitrogen dioxide (NO2) pollution levels were down on the year before.

Of the 52 monitoring locations in place, only seven breached the annual objective set at 40ug/m3 of NO2, which is currently legally binding under EU law.

It reestablished a downward trend of emissions – mostly produced by motor vehicles – that had been observed prior to 2018 when there had been nine breaches. This is compared to eight breaches in 2017 and 15 in 2016.

The latest air quality annual status report was considered by Dartford council at a policy overview meeting held last week.

Prior to the discussion councillors heard from environmental officers that while improvements in levels of air pollution have been seen across the borough in the last ten years, pollution levels remain high including at the Overy Liberty junction in the town centre.

They concluded: "A new air quality action plan is therefore required to set out new measures to seek further improvements."

But officers noted steady improvements were being made and are believed to have been driven by a change in transport use with a small but noticeable uptake in electric vehicles and a gradual shift away from diesel powered cars.

It was also revealed preliminary discussions with Bureau Veritas, which provides air quality testing services to the council, had indicated the authority may be in a position to consider revoking some of its monitoring sites.

The council is under a legal duty to report breaches and set up an Air Quality Management Area (AQMAs) at known hotspots.

Once one has been declared, it has to draw up a plan to manage the pollution and open that up to public scrutiny.

Dartford council currently has four AQMAs located at the approach to the Dartford Crossing, Dartford Town Centre, London Road, and the Bean Interchange.

Unfortunately, owing to the Covid-19 pandemic, work to review the existing sites has not progressed as quickly as was initially intended.

Nick Chapman, environmental protection officer, told councillors: "Once we have the recommendations from Bureau Veritas we will be bringing another report back which will explain recommendations for any AQMA that may be altered or changed.

"We may even determine that some may need to be increased. But we will be bringing a report back to explain that and for a decision by members."

This, it was said, would allow councillors, residents and other interested businesses and individuals an opportunity to consider the implications of any suggested measures and allow "the council to determine which actions it will seek to implement".

The leading cause of NO2 pollution is emissions from road traffic, which is also a major source of climate-wrecking emissions.

Exposure to excessive amounts of the gas irritates the airways of the lungs and can worsen the symptoms of respiratory diseases.

Cllr Danny Nicklen (Con), who represents Ebbsfleet where 15,000 homes are planned between now and 2031, said the volume of traffic and emissions, near the Dartford Crossing and the expanding Bean junction, is "already considerable".

He asked whether monitoring sites were being considered here as well as taking into consideration the planned London Resort theme park, which he said would "throw another dynamic into the mix".

Environmental officer Nick Chapman, said they were looking at and factoring in anticipated developments as part of the data.

He added: "Clearly the theme park, London Resort, will have a significant part to play in future, and we will be looking closely at the assessments that come forward in terms of air quality."

Last year it was revealed Dartford , Gravesham and Medway were among the worst affected areas for pollution with an increased risk of death .

The figures were released by Public Health England and based on levels of fine particulate matter called PM2.5.

It revealed Dartford had the second highest average daily level of air pollution of all local authorities in the south east of England . That's the equivalent of smoking 144 cigarettes a year.

However, the council does not currently monitor particles smaller than PM10 and does not have equipment capable of assessing PM2.5.

When quizzed on this aspect by Cllr Laura Edie (Lab), the council's environmental officer James Fox said they did have three monitoring stations for PM10 but this would require "quite an expensive retrofit" to convert to PM2.5.

It was added monitoring for these particles was currently only an obligation for central government rather than local councils.

Research commissioned by the British Heart Foundation has shown PM2.5 can have a detrimental effect to heart health, exacerbating existing conditions and increasing the risk of heart attacks and strokes.

Residents at Brent Way, near the Dartford Crossing, have repeatedly called for interventions against toxic fumes they can "smell and taste" .

Last year an alliance of parents, activists, cyclists and a countryside charity mounted a protest at the bridge to raise the profile of issues related to emissions.

It was organised with the help of Dartford mum Mandy Garford, who set up the Dartford Clean Air project after her newborn baby was left on life support following a severe respiratory infection.

The mum-of-four previously said before the incident she was a "passive bystander" but felt compelled to act in the face of growing evidence.

And now she has hinted there could be a scientific link between poor air quality and the severity of Covid-19.

Mrs Garford said: "People become unwell as a result of our air pollution, from low birth weight to respiratory illnesses, cancer, diabetes and even dementia.

"Multiple studies from around the world have suggested that there is a link between poor air quality and both the occurrence and severity of Covid-19."

"The case to effectively tackle air pollution has never been more urgent than during a respiratory pandemic."

She went on to explain during the beginning of lockdown Dartford residents were reporting being able to breathe better.

"There was a noteable change in the air quality," she said, before adding "slowly the traffic has crept back and the pollution with it."

"The case to effectively tackle air pollution has never been more urgent than during a respiratory pandemic."

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