In 2007/08, Dundee City Council spent £22,101 on the clean-up process. That rose to £24,011 in 2008/09 and by 2009/10 the cost stood at £24,458 – enough to provide a post for a new teacher, with change to spare.

Hardly a pavement in the city centre is free of the tell-tale white blobs and the council has tried to take steps to deal with the problem.

Special Gummi bins have been provided on lampposts in the city centre for the past two years

The problem, however, is persuading people to use them.

Once the gum has been spat out onto the roadway it takes up to five years to degrade and poses an unpleasant and unhygienic obstacle for passers-by to negotiate until it dries on to the road surface.

It then becomes hard to dislodge through standard street cleaning and can only be removed by labour intensive manual scraping or the use of expensive steam and chemical cleaners. In fact, though the cost of a piece of gum is just a few pence, it can cost anything up to £2 to clean up.

“There are a number of designated chewing gum bins placed in the city centre which are there to encourage people to place their gum in the bins instead of dropping it on the pavements, where it is very difficult and costly to remove,” said a council spokeswoman.

“Although these bins are there to remind people chewing gum to dispose of it wisely, it can also be placed in normal bins.”

It is little consolation that the problem is not confined to Dundee. Indeed, it’s been estimated the amount of gum spat out onto pavements in the UK each year would be enough to build three Big Ben clock towers — an image which no doubt rang a bell with London Mayor Boris Johnson when he called a “summit” to discuss the issue with gum manufacturers and clean-up experts earlier this month.

A recent survey by over 50s organisation Saga did not offer a solution to the problem of chewing gum litter louts, but did suggest a way to transfer the burden to those causing the problem. It found 82% of people in that age group would support a tax levy on chewing gum to cover the clean-up operation.