6. What else can enhance addictiveness of tobacco products?
Apart from their composition, other features of cigarette design can affect the composition of smoke and the size of smoke particles. The tar, nicotine and carbon monoxide levels in smoke are influenced by the ventilation through the paper and filter used in cigarettes, the packing of the tobacco and the precise shape of a cigarette.
Particle size is a likely influence on exposure to nicotine. Smaller particles are more likely to enter and deposit in the lower levels of the airways in the lungs. Increased ventilation can also affect nicotine dose by diluting the smoke.
However, smokers tend to compensate for lower doses of nicotine by puffing harder and more often, and breathing in the smoke more deeply. They may even block ventilation holes with their fingers to increase smoke concentration.
Research findings on particle size are complex, and incomplete, but particle deposition depends on respiration rate and inhalation depth as well as size. However, overall it appears unlikely that reducing nicotine dose makes addiction less likely. In fact, the reverse may be true. Animal studies suggest that cigarettes with high ventilation, often marketed as “light” or “low tar” may favour addiction because frequency of smoking is increased.