The health of children in the Lutterworth area could be affected if distribution hub Magna Park is allowed to expand, campaigners claim.
They say air quality in Lutterworth will deteriorate because of hundreds of extra lorry journeys an enlarged Magna Park would bring.
And they point to a recent report which said high levels of air pollution can stunt the growth of children’s lungs.
Graham Logan, a member of Cotesbach Action Group, one of the anti-expansion groups, said: “Lutterworth already has some of the worst air quality in Leicestershire. It’s city centre air in a rural town.
“If Magna Park is basically allowed to double in size, that means more traffic and more pollution.”
Mr Logan pointed to a recent report which said the growth of children’s lungs in some city areas was being stunted by pollution, particularly nitrogen dioxide (NO2) from diesel vehicles.
The research led by Professor Chris Griffiths, principal investigator at the Medical Research Council and Asthma UK Centre, focussed on children in east London.
The research found a direct link between air pollutant exposure and reduced lung growth.
“It goes to show that you can’t just pour lorries into Magna Park” Mr Logan said. “An expansion is going to hit everyone’s quality of life in the area, whether it’s through clogged roads or health issues.
“A Magna Park expansion would impact on everyone’s lives.”
Magna Park, a business zone west of Lutterworth, is currently the size of 550 football pitches, and employs 9,300 people.
There are three separate plans to expand it which will be considered by Harborough District Council later this year and early next year.
* A plan from Magna Park owners IDI Gazeley for a 590-acre extension to the business zone.
* A separate IDI Gazeley plan for a huge warehouse for DHL which alone will cover 25 acres.
* A plan from a separate company - Barwood Development Ltd - for a business zone called Symmetry Park immediately to the south of Magna Park.
The proposals, if they are passed, would more than double the size of the existing Magna Park.
Maggie Pankhurst of protest group Villagers Against Any Magna Park Development (VAAMPD ) said: “You had an article in the Mail last week about the low unemployment rate in this area.
“Already the vast majority of people who work on Magna Park do not come from round here.
“We don’t need more jobs here, especially the overwhelmingly low-wage jobs of a distribution centre.
“Because Magna Park is not on a motorway, it means lorries and of course all the cars of Magna Park workers have to come through villagers like Ullesthorpe, my village.
“And of course there’s no railhead at Magna Park - unlike DIRFT, which is only nine miles away.”