Toxic invisible pollutants could be causing health problems across Solihull - with one councillor warning people not to be lulled into a false sense of security 'just because we can't see it'.
Cllr Max McLoughlin (Green, Shirley South) has argued that there is a dearth of official data in areas such as Solihull to assess the true "magnitude" of the problem, which has been linked to serious illness and reduced life expectancy.
He also voiced fears that people sometimes tried to "dismiss" the issue by pointing out that Britain no longer suffers the pea-soupers or other more obvious signs of toxic substances in our atmosphere.
"That's a very important point to make," said Cllr McLoughlin. "Some people talk about the fact that they used to be able to see pollution ... but the pollutants that are causing health problems today are invisible and just because we can't see it, doesn't change the fact we are breathing it in."
His comments come following the release of a new report, detailing those areas of the UK found to be in breach of World Heath Organisation (WHO) air pollution limits.
Solihull does not feature on the list of 31 towns and cities around the country which were found to be in excess of the limit.
Nearby Coventry and Royal Leamington Spa were among those locations which the international public health agency did identify as cause for concern - with fine particle air pollution levels above 10 micrograms per cubic metre.
The report has been released a couple of months after the council provided its first update on efforts to monitor nitrogen dioxide in the borough.
Solihull had previously stopped taking readings several years ago, but a new programme to assess the situation got underway last July. The first 12 months of data is set to be made available later in the year.
At the most recent Full Council meeting, the Leader of Solihull Council, Cllr Bob Sleigh, insisted that air quality was a "key priority" for the authority.
"[It] is not necessarily simply a matter for one organisation, it covers public health, it covers the health service itself ... what it also covers is people who employ lots of people, to make sure they are given an opportunity to move to new technologies to actually reduce some of those air quality issues in the borough.
"We actually stopped [monitoring air quality] because we hadn't got any exceedances but we are doing that again."
He said that, once collated, the figures would be used to identify any issues that needed to be addressed.
Cllr McLoughlin said he had serious misgivings that councillors had not been provided with the data to date at a scrutiny board earlier this year, although public health officers had argued that 12 months' worth of readings were needed in order to avoid a misleading picture.
With a more rural character than many other West Midlands authorities, Solihull has generally been perceived to have less of a problem than other parts of the region, although the council's own officers note that "research into the health effects of poor air quality has demonstrated that there is no entirely safe concentration of air pollution."
In addition, the Green group previously flagged up concerns about air pollution levels at sites on the Stratford Road and Coventry Road - two of the busiest routes through the borough.