In an upward revision, the World Health Organisation has said that 4,9 million people die of smoking-related illnesses per year, nearly a fifth more than it had estimated two years ago.
The UN health agency also said its projection of 10 million deaths annually by the year 2030 was too low.
When WHO first started work on the convention two years ago, the estimated annual death toll stood at four million.
Other findings reflected
The new figure reflects research findings on the role of tobacco in tuberculosis and heart deaths in China and India, said Derek Yach, WHO executive director for non-communicable diseases.
The agency issued the figures in advance of a crucial round of talks opening next week in Geneva on an international anti-tobacco treaty.
The so-called Framework Convention on Tobacco Control is meant to be completed by next May. It includes provisions to clamp down on advertising and promotion, on second-hand smoking and on smuggling.
There continues to be disagreement over how tough the treaty should be and it is hoped that some of the differences will be ironed out in the two-week-long talks.
"This is a critical moment for the negotiations," said WHO Director-General Gro Harlem Brundtland in a statement. "The technical work is now complete. The time has come for all countries to show their determination about curbing the tobacco epidemic."
She urged governments to step up efforts to reach an effective agreement by the target date.
"Delays mean more deaths, and more children falling prey to tobacco," she added.
War on youth smoking
For WHO, the most important indicator of the death toll in the decades to come is youth smoking.
The health agency is helping to fund the Global Youth Tobacco Survey to assess the true scale of tobacco consumption among schoolchildren in countries around the
Results so far have been sobering: a US survey conducted in 2000 found that 23 percent of students in grades 6-12 used tobacco.
Tobacco companies stand accused of deliberately targeting young people by depicting smoking as glamorous and cool - a charge they vigorously deny.
China holds the key
Regardless of any decisions at the Geneva conference, the death rates will continue to rise to reflect the surge in smoking in developing countries, WHO admits.
"The death rates of today represent the smoking rates of 15-20 years ago. The smoking rates of today are the death rates of 15-20 years hence," said Yach.
China holds the key to the future death toll. There are currently 320 million smokers and one million deaths per year in the world's most populous nation.
An estimated 60-65 percent of men smoke and only 10-20 percent manage to kick the habit - far lower than in most European countries - according to Yach.
The government is slowly moving to institute controls such as smoke-free schools and restrictions on smoking in public places.
China, like India, want a ban on cigarette vending machines. But China's tobacco tax is a bigger source of revenue than income tax, which limits the incentive for the Beijing government to push through draconian measures to persuade people to quit. – (Sapa)
Degeneration of mental function
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