From Tiananmen Square to Oxford Circus, a global menace is stalking the unsuspecting: spat-out gum. As the authorities lose their patience, pressure is mounting on gum makers to invent non-polluting chewing gum - or be faced with the clean-up bill.
No gum control: Central London's remains of the day
Anyone who has ever tried to get up from a train seat only to find themselves still attached via a smelly string of someone else's chewing gum will need no convincing that gum can become a messy business.
But people spitting their gum out on the street causes its own set of problems, and the authorities finally seem to have had enough.
In China, military police have got down on their hands and knees to scrape discarded gum from Tiananmen Square. Chinese authorities are spending £100,000 trying to develop a strong enough chemical to shift the problem.
These are not guaranteed methods for gum removal
Small print at bottom of page of gum removal tips on NACGM website (see links)
In Singapore, a ban on chewing gum introduced in 1991 is still in place, although those who have medical certificates are allowed to carry on chewing.
In the UK, where £281m of chewing gum is purchased by consumers each year, councils up and down the country are determined to do something about it.
Glasgow City Council is one of those which wants the government to tax chewing gum to pay for the costs of removal. It spends £200,000 on cleaning gum off its streets.
And at the other end of the country, the picturesque market town of Barnstaple in north Devon is similarly plagued. Councillors who are sick of the unsightly pavement mosaic of trodden-in gum are desperate to find a solution, and are spending £16,000 on a one-off clean-up in the hope of putting people off dropping it again.
Central Beijing: Concerted effort to remove offending items
Tony Le Riche, town clerk for Barnstaple Town Council, says: "We are a holiday destination, the focal point for holiday makers who come to north Devon. So we want to try to maintain the characteristic beauty of the town."
Any number of other cities and towns - Leicester, Falkirk, Oswestry, Northampton, and Brighton among them - are in the same position.
Central London is no different. Oxford Street, bustling with shoppers, office workers and tourists all year round, poses particular problems for Westminster City Council. A spokesman says: "It's a serious filth that threatens the environment. We have 3,000 litter bins in Westminster, but people choose to drop their gum on the pavement instead of putting it in the wrapper.
"We spend a great deal of money removing it, which would be better spent on other services. We need a massive behavioural change to stop this problem."
The problem lies in the nature of the gum. The very properties which make it suitable to be chewed for hours on end are those which make cleaning it up a problem. Councils employ a number of different methods - spraying with jets of hot or cold water, treating with chemicals, even laser removal. Often they have to resort to scraping it off, but any of these can cause damage to pavements which are old or for some reason delicate.
High pressure hoses doing the job in Brighton
The bill for all this comes to £150m a year. The UK Government is hoping gum manufacturers will volunteer to help fund the clean-up, but is reported to be considering imposing a £50 fine on anyone dropping gum. If no voluntary deal is made, a new tax could be imposed on the gum makers, which they warn will be passed on to consumers. Some councils would go further if they could and ban gum altogether.
Research and development
So the prospect of a non-polluting gum certainly has its attractions. Food development expert Professor Martin Chaplin of London South Bank University says it is clearly possible to make a less sticky gum, which could be more easily removed.
But, he says, if it was any less acceptable to consumers than present gum, there would be no incentive to manufacturers to develop it. "Stickiness is part of its appeal," he says, warning that in any case, "making it less sticky against one material, eg pavement, does not mean the same with others, eg clothes".
His preferred route would be to make it biodegradable, but again he wonders who would pay for the research and development, or the costs of production which would almost certainly be higher than conventional gum.
You dirty, dirty people
Amy Chezem, of the US Association of Chewing Gum Manufacturers, says gum makers recognised the problem is a worldwide one, and are spending cash in trying to find a solution.
"A lot of manufacturers are researching how to tackle the problem," she says. "Some advances have been made, but I think the prospect of a biodegradable gum is some way off. We are trying though."
Until that time, most hopes are resting on being able to change people's behaviour.
Ginette Unsworth, of environmental campaign group Encams (formerly the Tidy Britain Group), says there is only one long-term solution.
"That is to stigmatise it so much that people will feel uncomfortable dropping it."
So chewers beware... be prepared for some seriously hard stares.
Send your views on this story using the form below:
A few months ago students of the Manchester Metropolitan University highlighted the problem of gum on the pavements by drawing colourful rings around the offending mess with chalk. This was a very good visual statment that certanly made me think twice about the problem and yes I always put my gum in the bin now.
John Clarke, Manchestrer England
Sticky chewing gum discarded on the pavements is a big problem in my home town of Stafford, where we did have a nice pedestrian zone which is bnow mottled with discarded gum, but no worse a problem than the one caused by people who discard their cigarette buts at will on the pavement or through their open car windows whilts driving. Personally I vote for on-the-spot fines for anyone caught doing either of these disgusting habots.
Having read the article I looked at the sole of my shoe to find someone's discarded gum with someone's fag butt stuck to it. Very pleasant! The streets are littered with used gum and it was about time that the manufacturers paid a price which reflected the true environmental costs of the product that they sell. Let's tax the cause to pay for the effect.
James Callander, Pathhead, Scotland
It should be banned altogether. if i threw an empty crisp packet on the floor, someone would probably make a comment. BUT, if i spat out some gum or threw a finished cigarette on the floor, no-one would bat an eyelid. It is a disgusting habit which should just be banned. The idea about making the people who chew gum pay for the clean-up via tax is a good idea.
I've been chewing gum for almost 25 years now and I've never dropped a piece of gum in a place where it could cause a problem to somebody else (honest!) If I can bin my gum over the years, why can't everyone else?
You chew it, you bin it.
It would cost a fraction of the clean-up costs to prevent the problem by employing people to patrol the streets who have the power to issue fines to those dropping gum (or other litter). Currently people are rarely fined for littering, as there is no-one with any powers around to see it happening.
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