british american tobacco p.l.c. sustainability report 2009 - Spotlight on science: clinical study


Study title: “To compare the exposure levels of selected smoke constituents as determined by biomarkers of exposure, filter analysis, sensory perception and other parameters when smokers using commercial cigarettes are switched to novel cigarettes.”

For more information, please see the Current Controlled Trials website, where the study is registered, at Opens in new window.

The purpose of the study was to determine whether the reduced levels of toxicants in the tobacco smoke, as observed using machine smoking, would result in reduced exposure to those toxicants in smokers. A variety of approaches were used to reduce the smoke toxicants across the three prototypes being tested. These included tobacco treated to reduce the plant constituents that give rise to some toxicants, tobacco processed to include glycerol, which dilutes the smoke, and materials in the filter that trap volatile toxicants. This was the first clinical study in which we had tested these technologies.

One of the technical challenges we face will be to improve the tobacco treatment processes in order to produce sufficient amounts for use in larger studies.

The study involved 300 people of which 250 were smokers and 50 were non-smokers. The non-smokers acted as a control group so we could assess background levels of biomarkers in those not exposed to tobacco smoke. All attended a clinic where medical histories, smoking histories, and physiological measurements, such as blood pressure and lung function, were taken as well as samples of blood, urine and saliva.

The smokers were divided into two groups, one of which smoked 6mg ISO tar yielding conventional cigarettes and one of which smoked 1mg ISO tar yielding conventional cigarettes.

During the study, some smokers were asked to switch to one of three prototype products being tested. Others continued with their regular cigarettes. The aim was to determine whether the smokers who switched to a prototype product had lower levels of biomarkers of exposure for certain smoke toxicants in their biological fluids than those who continued to smoke their regular cigarettes.

We expect to complete the data analysis in 2010 and to submit the results for publication in a peer-reviewed journal.