Poor air quality as a result of traffic build up along Warwick Road in Kenilworth is getting worse as numbers have rocketed above recommended levels in two years.
And exhaust fumes from family cars have been blamed as the biggest contributors to the worsening problem.
Warwick Road is the main route for cars and lorries passing through the town and was part of the Low Emissions Zone study to monitor traffic flow and problems.
The new report released to Warwick District Councillors shows emission levels at 44 micrograms -higher than the national guideline of 40 for healthy air quality.
But the figure has shot up from just 29 micrograms in 2010 causing concern about the future.
Councillors will now look into the report to try to find a way around the problems.
Richard Hall, Warwick District Council’s head of health and community protection, admitted that originally it was assumed heavy goods vehicles and buses would be responsible for most of the nitrogen dioxide emissions.
But it is domestic diesel exhausts that are instead the main problem.
Mr Hall said: “Domestic diesel fuel is the main culprit, but with the increasing efficiency of engines the level of emissions has come down.
“What our report shows is that simply banning HGV vehicles from a town is not going to improve air quality - instead we need to look at ways of reducing the number of cars.
“In Warwick, as in other towns, enclosed streets are the reasons the levels of nitrogen dioxide build up.
“These levels only extend for a short distance and can quickly disperse.”
District councillor Ann Blacklock (Lib Dem) said they would now have to work with Warwickshire County Council, which is responsible for traffic, to tackle the issue.
“The problem is we don’t want this traffic just going down other roads to disperse the problem,” she said.
“Sadly there are a lot of lorries that use Warwick Road as a short cut or convenient route through Kenilworth. They are not stopping in the town.
“People walking and shopping won’t be affected, but it is the people working on Warwick Road and in The Square all day long who will suffer as a result.”
John Brightley from the Friends of the Earth in Kenilworth said:“Friends of the Earth encourages people to walk, cycle or use public transport as much as possible so that emissions are minimised. We support council policies to help this happen.”
The results should build a stronger case for park and ride schemes and cycle lanes.
Increasing air pollution is one of their key arguments against the thousands of extra homes being considered in the revised district plan.