In the latest damaging disclosure for the tobacco industry, researchers from Ash, the anti-smoking group, and the Imperial Cancer Research Fund have found documents showing that the industry has known since the late 1970s that smokers compensate for the lower dose of nicotine and tar in cigarettes such as Silk Cut Ultra or Marlboro Lights by taking more or deeper puffs.
The charities claim that the manufacturers have cynically designed cigarettes to give low tar readings but deliver high tar and nicotine to the smoker. Tar and nicotine levels are measured by a smoking machine that takes standard puffs through its steel "mouth". But smokers do not smoke like machines and tend to inhale more deeply or suck more often when nicotine levels are low.
Dr Martin Jarvis, of the ICRF Health Behaviour Unit, said: "It is scandalous that the tobacco companies have known this for so long, but continued to develop products designed to make compensation easy, while at the same time marketing them with a healthy ... image."
Low-tar cigarettes do not contain low-tar tobacco, but have ventilation holes around the filter so that more air is drawn in. To satisfy their craving for nicotine, smokers may subconsciouslyblock the holes in the filter with fingers or saliva.
Silk Cut Ultra is rated at 1mg of tar, against 12mg for a conventional Benson and Hedges cigarette, but that did not mean that it carried one twelfth of the risk, Dr Jarvis said. Tests had shown that blocking the ventilation holes raised the tar level to 12mg.
Silk Cut Ultra was featured in an advertising campaign at the turn of the year which used the slogan "JAN ONE", to suggest that switching to the brand would be a good New Year's resolution, instead of giving up.
Dr Jarvis said: "The numbers on the cigarette packs are worse than useless and may be dangerous and misleading. Because of compensation for nicotine, smokers can and do get as much nicotine from these low-yielding cigarettes as from standard ones. It is worrying that people may be switching to these products rather than quitting.
"We hope that smokers will recognise that low-tar cigarettes are at best a fool's paradise and at worst a con-trick and begin the process of giving up."
Tobacco industry documents dating from the late 1970s and early 1980s show that executives recognised the compensation effect. A British American Tobacco memo in 1977 asked: "Are smokers entitled to expect that cigarettes shown as lower delivery in league tables will in fact deliver less to their lungs than cigarettes shown higher?" It answered its own question in a 1984 memo: "Irrespective of the ethics involved, we should develop alternative designs (that do not invite obvious criticism) which will allow the smoker to obtain significant enhanced deliveries should he so wish."
Clive Bates, director of Ash, said: "So-called low-tar cigarettes are a grotesque confidence trick that has been running for 20 years. Brands described as mild, light and low should not even be on the market."
He said he had written to Tessa Jowell, minister for public health, seeking the immediate removal of the tar and nicotine numbers, a new pack warning about nicotine addiction, an end to branding that implied a health benefit and regulations to control the harmful components of tobacco.
John Carlisle, spokesman for the Tobacco Manufacturers' Association, said: "Low-tar cigarettes have been produced in response to consumer demand but the way they are smoked is up to the consumer. If they choose to tamper with the filter there is nothing we can do about it."Reuse content