A gradual reduction of nicotine levels of cigarettes was proposed by Benowitz and Henningfield in 1994.10
Whereas this proposal envisioned a reduction to non-addicting nicotine dosage levels over a decade or longer, recent research studies using reduced nicotine content cigarettes to aid smoking cessation have raised the possibility that more rapid lowering of nicotine content might be equally or more effective.11
A reduced nicotine cigarette policy would have to apply to all manufactured cigarettes and potentially to tobacco sold for roll-your-own cigarettes, small cigars and perhaps ultimately to all other combustible tobacco products in a particular country.
One of the assumptions implicit in a nicotine reduction strategy is that there is a threshold nicotine exposure that is necessary to produce reinforcing effects and to sustain addiction. It is likely that there is no single threshold that applies to all people. There is considerable individual variability in dose sensitivity to all drugs, including nicotine. The key questions is: what level of nicotine reduction is required to prevent novice smokers from becoming addicted and to help established smokers to be readily able to control their use of cigarettes—that is, to quit smoking more easily when they decide to do so?
The Food and Drug Administration (FDA) was given the authority to regulate cigarette addictiveness through the Family Smoking Prevention and Tobacco Control Act.12
Although it precludes ‘reducing nicotine to zero’, the law does not prohibit the FDA from setting standards for nicotine content that would prevent cigarettes from being capable of causing addiction. Currently, most manufactured cigarettes contain 10–15 mg of nicotine per cigarette. On average, smokers systemically absorb 10% of the nicotine contained in the rod, with a typical systemic intake of 1–2 mg of nicotine per cigarette.13
We made an initial estimate that reducing the total nicotine content of cigarettes to 0.5 mg per rod would minimise the addictiveness of cigarettes.10
It was assumed that these doses would not produce psychoactive and rewarding effects, but such effects might occur at lower doses in non-tolerant children and adolescents.14
A more recent analysis suggests that the maximum allowable nicotine content per cigarette that minimises the risk of central nervous system effects contributing to addiction may be lower.8
Sofuoglu and LeSage reviewed the question of nicotine addiction threshold as a target for tobacco control.15
They noted the challenges of determining daily addiction thresholds and suggested that the threshold for nicotine regulation should be based on the amount of nicotine per unit dose (eg, per puff from a cigarette) that produces reinforcement—the ‘nicotine reinforcement threshold’. There are undoubtedly many other tests that may be employed to determine the maximum allowable level of nicotine per cigarette, just as many methods are used to comprehensively assess the addictiveness of drug products.16–18
Regardless of which methods are used, the standards for cigarette design, including nicotine content, need to ensure that no populations of concern (including children) would derive reinforcing effects from cigarette smoking or be readily capable of obtaining sufficient nicotine to produce addiction. Furthermore, it will be important that the policy be implemented with sufficient flexibility to further reduce the allowable nicotine level if surveillance and relevant biomarkers indicated that reinforcement and addiction continued to occur.