The City of Lincoln Council has described “danger” signs in the city centre warning of a health risk due to high pollution as “misleading”.
Around six signs can be found at the bottom of Lindum Road and down Broadgate at traffic lights and pedestrian crossings.
They appear to include the city council’s logo and warn people that air pollution in the area may “adversely effect” their health or “cause premature death”.
No one has yet come forward to claim responsibility for the signs.
City council officials said the authority is not responsible for the signs and added that air quality has improved in the city.
The council were not able to share up-to-date air quality readings for the Broadgate area when approached.
Ian Wicks, pollution control officer at the authority, said: “Firstly, the signs are misleading in that anyone walking or cycling in the city centre is highly unlikely to be exposed to the limits of Nitrogen Dioxide that have been imposed by the government.
“In fact, we’ve been working on air quality for many years and the situation has got a lot better in that time, even leading to the city’s Air Quality Management Area being reduced in size.
“Where there are areas of increased pollution in the city, the principal source is road traffic. We are therefore working with Lincolnshire County Council on the development of their revised Transport Strategy to keep Lincoln as free from traffic as possible.
“Once the Lincoln Eastern Bypass is open, it will alleviate traffic in the Broadgate area, and this in turn will improve air quality further.”
The authority currently has an Air Quality Management Area in place which covers Broadgate and other main roads in the city.
It means the city council monitors the areas as they are likely to exceed the air quality objectives.
The authority is expected to declare a climate emergency tonight at its full council meeting.
It would become only the second authority in the region to do so after North Kesteven District Council called an emergency earlier this month.
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