|Dunhill Early Morning Pipe Tobacco, 1990's Murray (Photo credit: wikipedia)|
Some of these additives may cause tobacco dependence as tobacco is the main source of nicotine that is widely available. They can affect the addiction or dependency these products can cause or simply make smoking more attractive for the people.
The number of additives is so great, and the chemical mixtures that are produced so complex that to measure the individual effects of additives used in cigarettes is very difficult and expensive. Much of the research is limited and made by the tobacco and cigarette industry itself, so no one can be sure in their results.
How can we assess tobacco additives, what is the effectiveness of current methods and what is currently known of their effects?
Questions on tobacco additives that we will look at more in deep
- What are the ingredients of tobacco products ?
- How can we analyze tobacco products and their ingredients?
- The development of nicotine addiction it depend on the dose?
- Additives they make the most addictive tobacco ?
- What other factors can increase the addictiveness of tobacco products ?
- Additives they make tobacco more attractive ?
- What additional research is needed ?
- The answers to these questions are a faithful summary of the scientific opinion produced in 2006 by the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) :
- " Addictiveness and Attractiveness of Tobacco Additives" More ...
Smoking is both addictive and harmful. For example The EU directives provide a regulatory framework for tobacco products to protect public health. The latter includes the possibility of banning additives, as some are likely to increase the addictiveness of tobacco products.
This report examines the criteria used to evaluate the additives , their role in tobacco products , and how the design of these products can affect their addictiveness and attractiveness.
2. What are the ingredients of tobacco products ?
The majority of smokers smoke cigarettes. A cigarette is a widely manufactured commercial product, carefully designed to deliver a specific dose of nicotine. The cured tobacco is processed and packed to create a standardized tobacco product. The characteristics of each brand depends on the type and the mix of tobacco used, how they are dried, the additives used and other technical characteristics of the cigarette. These factors can affect for example the amount of various substances contained in the smoke, combustion characteristics, and the nicotine delivery dependent of the smoke particle size.
In recent decades, the additives were introduced in increasing numbers and cigarettes now contain about 10% additives. There were nearly 600 different additives officially recognized. They affect the characteristics of the smoke, as its color, pungency, smell and aroma.
The main tobacco additives are sugars, which are also naturally present, and humidifiers. They also include preservatives and many flavors such as cocoa, licorice, menthol and lactic acid.
The hand-rolled cigarettes ( also known as: Roll-your-own cigarettes, RYO, roll-ups, rolls ) cigars, water pipes and smokeless tobacco products, may also contain additives and are only a small portion of the total tobacco products available on the market.
3 . How can we analyze tobacco products and their ingredients?
Tobacco products are addictive and their addictive power is higher than that of pure nicotine. There remains a need to establish methods to measure the addictiveness of tobacco with and without additives. However, it is difficult to distinguish experimentally the possible health effects of those artificial chemical additives and the ones normally present in tobacco smoke.
Tests in animals and humans are used to evaluate the additives content and properties. While studies on humans can bring more light to both the addictiveness and attractiveness, studies on animals can only relate to the first of these two factors by obvious reasons.
|Nicotine (Photo credit: wikipedia)|
It is difficult to conduct systematic experiments in which specific additives are present or absent. Testing of the addictiveness of tobacco products on people poses serious ethical problems, especially if one wants to study their effects on children or non-smokers. For these reasons, current methods of assessment of additives are not adequate .
4 . The development of nicotine addiction depends on the dose?
The addiction to nicotine has been studied in great detail, since multiple studies have been conducted on the absorption and the metabolism of nicotine present in the smoke and the variety of its effects on the chemical neurotransmitters in the brain. While studies on animals indicate that the pure nicotine is only weakly addictive, data on the human use of the drug indicates that the addictive potential of the tobacco is very high.
Individual responses also vary widely, but the nicotine dependence is correlated with the number of cigarettes smoked per day.
Studies on animals show that the reaction to the nicotine is dose-dependent: it deepens with the increasing of the dose and then decreases again - the dose- dependency has therefore the shape of an inverted U. This trend is similar to those presented by other drugs.
5 . Are additives making the tobacco more addictive?
Here are some of the ways additives increase the additiveness of tobacco:
- directly by increasing the overall content of nicotine
- increasing the bioavailability of nicotine, so the reaction of the body is more intense
- facilitating the ingestion of the cigarette smoke
- producing substances in the smoke that increase nicotine addictiveness
- altering the properties of tobacco smoke, such as the size of smoke particles.
None of the tobacco additives was identified as addictive by itself. But some might have an strong influence on nicotine addiction. There is mainly research data on sugars, which are added to many tobacco products, but which are also naturally occurring in tobacco leaves .
The combustion of tobacco generates many chemicals and sugars called aldehydes, including acetaldehyde. It is believed that the latter increases the levels of a particular class of neurotransmitters, such as dopamine, by inhibiting the enzyme that normally reduces the production of dopamine in the body. However, it is not conclusive shown that the presence of aldehydes in the smoke are directly increasing the levels of these chemicals in the blood, so further research is needed.
Ammonia and its compounds are added to certain tobacco products to reduce the acidity of the smoke. It was believed that this would increase the absorption of nicotine, which is inhibited in an acid medium. However this addition seems to affect the absorption of nicotine through the mouth, whereas smokers absorb most of the nicotine through the lungs. The ammonia-enriched tobacco products do not appear to increase the levels of nicotine in the blood significantly.
6 . What other factors can increase the addictiveness of tobacco products ?
Aside from additives, the way cigarettes are made, affects the composition of the smoke, including tar level, carbon monoxide and nicotine content, and the size of smoke particles .
The particle size can affect the nicotine exposure, because smaller particles penetrate deeper into the lungs . If more air is mixed with the smoke by designing a better ventilated cigarette, the absorption of nicotine is reduced by smoke dilution.
However, smokers tend to smoke enough to receive the dose of nicotine they need, regardless of the composition of the smoke. If the cigarette delivers less nicotine they inhale harder and more often.
7 . Additives are making tobacco products more attractive?
Additives can make the act of smoking more attractive - for others as for the smoker - and reduce the odor persists, as well as mask the smell of smoke. They can make it easier for someone to start smoking by making the smoke lighter, sweeter and less pungent in the throat. The bitterness can be altered by changing the proportion of nicotine relative to tar, or by adding flavors that give the impression that a brand of cigarettes is particularly "soft".
It is very difficult to assess the role of specific substances in increasing of the attractiveness of smoking. Most of the information that is available is mainly on the menthol, used by popular brands of cigarettes mostly in the United States. Menthol reduces the bitterness and promotes a deeper inhalation of smoke. In the United States, a much higher proportion of African Americans smoke menthol cigarettes than European Americans.
The available data don't allow any conclusion regarding the overall effect of additives on the use of tobacco products. The prevalence of smoking ( i.e. the number of smokers ) is stable or declining in most EU Member States. 2006 statistics show that 27.5% of adults smoked in the EU - 33.2 % of men and 21.8% women - about the same level as in 2002 . Average smoking is more common in the Member States of Eastern Europe .
It is possible that the aromas are used to target young people, and there is evidence that young smokers are more likely to use flavored cigarettes. However, statistics show that British preferences in terms of brands for adults and children are smoking rather similar . It also seems that in the UK market, which is dominated by local brands, cigarettes sold as " additive free " could be more successful.
8 . What additional research is needed ?
It remains for further studies to be carried out on certain aspects of additives, addiction and attractiveness of tobacco products. It would be useful to consider the following questions:
The composition of smoke from tobacco products other than cigarettes
Neurophysiology of tobacco addiction
The role of sugars in the addictiveness of tobacco products
The criteria for measuring the attractiveness of tobacco products and additives
Studies of the favorite brands of new smokers and the reasons for choosing these brands.
Studies of this type could be conducted through European collaborative projects , or creating a European Institute for Research on drug use .