http://www.cancerresearchuk.org/about-us/cancer-news/news-report/2015-06-10-tobacco-additives-may-have-helped-promote-addiction
Tobacco researchers identified additives that could have made cigarettes more acceptable and addictive, according to a new analysis of tobacco company documents.
It suggests that chemical additives, called pyrazines, were identified and began to be included in the ‘recipe’ for some tobacco products in the 1960s and 70s to make low-tar, or ‘light’, cigarettes, taste richer and smoother.
“It fits into the familiar pattern of manipulation we’ve come to expect from an industry responsible for millions of deaths worldwide each year” – Professor Linda Bauld, Cancer Research UK
The analysis of documents from tobacco giant Philip Morris was carried out by a team from Harvard School of Public Health in Boston.
Writing in the journal Tobacco Control (link is external), they suggest that the compounds may also reinforce the addictive qualities of nicotine.
According to Professor Linda Bauld, cancer prevention expert at Cancer Research UK, the findings are not unexpected.
“It’s not surprising to see reports suggesting that a tobacco company may have been altering its deadly products to try to keep smokers hooked – it fits into the familiar pattern of manipulation we’ve come to expect from an industry responsible for millions of deaths worldwide each year,” she said.
Nicotine dependence is primarily caused by nicotine prompting the release of a brain chemical called dopamine – which is involved in pleasure, arousal and mood change.
But growing research suggests that nicotine alone can’t account for the intense addictive properties of smoking tobacco.
The investigation looked at internal documents from Philip Morris made available in the late 90s as a result of litigation. It also reviewed scientific research on the composition and role of cigarette additives.
The documents analysed go back as far as the late 60s, as tobacco’s dangers became apparent and ‘low tar’ products became more desirable.
They document how the company discovered that pyrazines could curb the harshness and irritating effects of tobacco smoke, thus easing the inhalation and uptake of nicotine.
Several pyrazine derivatives also seem to have a role in boosting the amount of dopamine released during smoking.
The researchers expressed their concern over the role the additives may play in nicotine dependence.
“The [effects of] pyrazine flavour additives might provide cues for reward-related learned behaviours, and could play a critical role in the development, maintenance, and relapse of tobacco dependence,” they wrote.
“Taken together, pyrazines appear to increase product appeal and make it easier for non-smokers to initiate smoking, more difficult for current smokers to quit, much easier for former smokers to relapse into smoking,” they wrote, concluding that this “may mask the risks of both active and passive smoking.”
Professor Bauld stressed that, no matter what additives are present in tobacco, “there’s no such thing as a ‘safe’ cigarette”.
“That’s why there needs to be continued, comprehensive, strategic action on smoking – on all fronts – to realise the vision of a society free from the harms of tobacco,” she said