If such growth continues, by about April next year, enough mobiles will have been manufactured to supply half of the world's 6.5 billion people. Hong Kong, with the highest penetration rate - 125.1 per cent - is setting the tone for all and sundry to follow.

Roll back the clock to 1991, when the International Telecommunication Union estimated there were just 16 million mobile subscribers worldwide, and you get a sense of where we have come from - and, more frighteningly, where we are heading.

It's enough to make your ears bleed, just thinking of the clamour of all those ringtones.

There is a problem with mobiles that is even more worrying than the noise they make, though. Although seldom mentioned in Hong Kong, it's starting to concern the more environmentally conscious denizens of our planet.

The typical user in a developed society gets sucked, by clever advertising, into buying a new phone every 18 months - I dare not think what the rate is in Hong Kong. So there are a lot of old models about.

Being in the heart of mobile-hungry Asia, when we trade in a phone - or give it to a kindly looking old woman in the street - it will generally get sold on again, to live another day.

But the fate of those that get drenched by a wave at Shek O beach (as one of mine did) or meet a sticky end in a glass of beer (as did its successor) is a rubbish bin. Herein lies the problem: mobile phones, like computers and most other things electronic, are full of hazardous materials. The typical mobile and its accessories contain cadmium - the seventh most dangerous substance known to humanity - and a host of other metals that should not, under any circumstances, get into your bloodstream in sizeable amounts: lead, nickel, mercury, manganese, lithium, zinc, arsenic, antimony, beryllium, copper, gold and silver.

None of these are biodegradable. When mobiles are tossed into a landfill, such metals can leach into the soil, then find their way back to us through the food chain. This information should serve as adequate warning never to ingest your mobile.

Fortunately, the clever people of Finland - who gave us the mobile manufacturer Nokia - have come up with a solution for phones that do not work and cannot be salvaged. In the small town of Savanlinna, near the border with Russia, they staged the seventh mobile-phone-throwing world championship at the weekend.

More than 100 competitors - from as far afield as Canada and Belgium - took part. The gold medal winner was a Finn, Lassi Etelatalo, who threw his old Nokia 89 metres.

To prove that the titles are as much about showmanship as exercise, Dutchman Elie Rugthoven failed to register the second-farthest throw - but still won silver because of a superb phone-juggling performance.

I am not one to brazenly steal someone else's idea, so will instead borrow this brilliant method of combining athleticism with protecting the planet from toxic waste - by adapting it to Hong Kong's particular environment.

I hereby propose the inaugural Phone Flinging Festival, a compulsory contest of accuracy for people with more than one mobile. They will be required to throw their excess handsets into the open cargo holds of planes bound for the headquarters of mobile phone manufacturers - the people who should sort out the mess they've created.

Peter Kammerer is the Post's foreign editor.