Chemical laboratory tests are used to assess the extent to which levels of various smoke toxicants have been reduced compared to a conventional cigarette
Our current research focuses both on developing potentially less harmful tobacco products – whether combustible (such as cigarettes) or smokeless – and the science required to assess them.
Our research into products that are smoked focuses on understanding cigarette smoke chemistry and smoking behaviour, and evaluating the biological indicators (known as biomarkers) of exposure and harm, in order to develop and test potentially less harmful tobacco products. These are often referred to as potential reduced-exposure products or PREPs, a term introduced by the US Institute of Medicine (IOM).
The science is not simple for products that are smoked and we still cannot be certain what might constitute a reduced-harm cigarette. There are three scientific challenges that will take time to resolve:
- Identifying which toxicants in smoke are the most significant for disease and devising the methods to measure smokers’ exposure to them;
- Developing products that may reduce exposure to these significant toxicants and demonstrating that they do;
- Assessing whether this reduced exposure actually reduces the potential risk of tobacco-related disease.
Before a product can be described as a PREP, it must be evaluated through a set of agreed tests known as an assessment framework. Currently, there is no recognised assessment framework for PREPs and we are working to develop one that will be acceptable to independent bodies.
Our approach assumes that a considerable amount of data will be needed to provide independent bodies with a reasonable level of confidence that a PREP will result in some reduction in risk and possibly in harm. That data will come from laboratory studies, clinical studies and long term evaluation.
Laboratory and clinical studies
Chemical laboratory tests are used to assess the extent to which levels of various smoke toxicants have been reduced compared to a conventional cigarette.
Biological tests can then give an early indication of whether a new product could reduce exposure to smoke and have a lesser biological effect.
Tests can also be undertaken to compare a new product to conventional tobacco products and provide assurance that the risk of harm has not increased for other reasons. While some laboratory testing methods are already established, others still need to be developed and validated.
2009 clinical study
In 2009 we began a clinical study involving three cigarette prototypes designed with combinations of new technologies that reduce some of the toxicants in smoke, as measured by smoking machines.
The study targets well-recognised toxicants implicated in smoking-related diseases, although it is too early to know if we have targeted all the relevant toxicants or reduced them enough to make a difference to potential health effects.
Because people don’t smoke the same way as machines do, the study aims to find out if exposure to the toxicants is also reduced when the prototypes are smoked by real smokers in their normal way.
Our scientists have used several modifications to reduce the toxicants including leaf treated to reduce tobacco constituents that give rise to some of the toxicants in smoke, tobacco processed to include glycerol to dilute the smoke and modified filter materials.
The aim is to determine whether smokers who switch to a prototype product have lower levels of biomarkers of exposure in blood, saliva and urine than those who smoke regular cigarettes.
While the study can find out whether the modified cigarettes do help to reduce exposure to toxicants, it will not tell us whether they are less harmful. There is a lot more work to be done over the coming years before we can assess whether lower toxicant exposure might reduce the risk of smoking related diseases.
Epidemiological evidence, particularly from Sweden, suggests that using smokeless snus is substantially less hazardous than cigarette smoking because it is not associated with increased risks of lung cancer, oral cancer and chronic obstructive pulmonary disease. However, smokeless does not mean harmless.
Our research programme on snus is focused on two areas:
- laboratory studies on the chemistry and toxicology of snus
- consumer studies on dependence, use and risk perception.
We publish research in peer-reviewed journals, present our findings and views at scientific conferences and we seek to collaborate with others – particularly members of the academic and public health communities – to improve the breadth and quality of our research.
We also have a science website, through which we share our research findings with external audiences. The site is written by scientists for scientists with an interest in tobacco-related research or related disciplines. We welcome comments from the scientific community on this website and our research.