Tobacco companies are funding research into infertility in a bid to counter widespread evidence that smoking drastically undermines the chances of conceiving.
Philip Morris, one of the world's largest cigarette firms, is being accused by the anti-smoking lobby of attempting to deceive smokers into believing they can improve their chances of having children if they take vitamin supplements.
Campaigners such as the anti-smoking charity Ash say that tobacco giants have turned their attention to treatments which may boost fertility in a "cynical" attempt to change their image.
The criticism is in response to the publication of a Philip Morris-backed study this week which concludes that taking supplements of the mineral selenium, which is found in shellfish, as well as vitamin E tablets can boost fertility in men who have low-quality sperm.
However, the study, carried out by experts in Montreal in Canada, fails to make any mention of the fact that smoking drastically undermines sperm quality and that any benefits of vitamin and mineral supplements would be cancelled out by the effects of cigarettes.
The research comes as changing attitudes to smoking in the West have forced tobacco companies to seek out new markets in the developing world.
Cigarette sales in western Europe and North America have collapsed amid tougher anti-smoking laws, higher tobacco taxes and a growing awareness of the health implications. In Britain the number of smokers has fallen dramatically over the past 30 years or so. Where half the male population smoked in 1974, by 2003 that figure was down to 28 per cent; numbers of women smokers have fallen from 41 per cent to 24 per cent over the same period.
In turn, cigarette manufacturers are focusing their attention on eastern Europe, Africa and the Far East.
Tobacco companies have also been accused of turning a blind eye to cigarette smuggling in order to flood new markets with their product. And they have faced criticism for launching aggressive marketing campaigns, which would be banned in the West, linking tobacco with sex, youth and glamour.
Health workers say that the tobacco firms are taking advantage of looser trading restrictions and lower levels of health education to ensnare a new captive market of nicotine addicts.
"By funding research they create the impression that there is an ongoing debate about the health impact of smoking," said John Britton, professor of epidemiology at Nottingham University.
"They fund research in the developed world which affords a certain credibility, but all the time they carry on pushing the product in poor countries."
The new research is the latest in a series of studies used by the tobacco lobby in an attempt to downplay the potential health hazards of smoking.
In 1999, research carried out by the Parkinson's Institute in California showed that smoking may lessen the risk of Parkinson's disease. The study of 161 pairs of twins suggested that smokers were apparently protected from Parkinson's and was seized upon by pro-smoking campaigners.
But the doctors who carried out the research said that it was not possible to say which chemicals were responsible for the lower rate of disease, and stopped short of recommending cigarettes to prevent Parkinson's. Other studies quoted by pro-smoking campaigners have suggested that smoking may reduce the risk of hypertension and certain forms of cancer. They have also suggested that smokers' children may suffer from lower levels of eczema and asthma.
Dr Sinead Jones, who recently authored a report on smoking and reproductive health for the British Medical Association, said that the tobacco industry was more interested in maintaining its market than deepening medical knowledge. "The links between smoking and lung cancer were first detected in the 1950s, and since then the tobacco companies have been very active funding research, to increase their credibility in the scientific community and to confuse people about the risks of smoking," she said
"The real reason they invest in research is to increase their profits."
And a spokeswoman for Ash said it was "ludicrous" to urge people to take vitamin supplements to improve fertility if they are smokers. "They are very good at masking contradictions. It is bizarre when smoking is one of the most important causes of infertility problems and the first thing a GP would advise is to quit."
This is not the first time that the benefits of selenium have been highlighted by research which is either funded by or has links to the tobacco industry. The mineral has already been shown to lower the incidence of lung, colorectal and prostate cancer.
The power of tobacco companies to plug their products has been greatly reduced since the introduction of worldwide bans on overt advertising of cigarettes.
Since December 2004, all cigarette advertising in the UK has been banned apart from small images of products on vending machines, and tomorrow the House of Lords will vote on measures to restrict smoking in public places.
In response, tobacco companies have become increasingly inventive in finding new ways of raising awareness and marketing their products.
Smoking is one of the major causes of infertility in both men and women. Some studies have found that substances in cigarette smoke are toxic to the testes and ovaries. Smoking also reduces the quality of sperm. Women smokers also take longer to conceive, while the rate of miscarriage is substantially higher.
But Philip Morris denied that its motives were cynical in helping to fund the fertility research, which was carried out by researchers at the Hospital Saint-Luc du Chum, in Montreal.
A spokesman said that the company's aim was to improve public health and that it had no influence over the research that it funded.
"We make a product that is addictive and causes disease and one of our goals is to reduce the harm," he added. "There is no attempt to hide the fact we are funding research. This is always made clear so that the findings are transparent and independent."
Additional reporting by Hazel Francis
Beyond satire: 'I speak on behalf of cigarettes...'
Dialogue from Thank You For Smoking released in the UK last week. Nick Naylor (played by Aaron Eckhart) is a spokesman for the tobacco lobby
Nick Naylor: I speak on behalf of cigarettes.
Child: My mommy says that cigarettes kill.
NN: Now, is your mommy a doctor?
NN: Is she some kind of scientific researcher?
NN: Now she doesn't exactly sound like a credible expert, does she?
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