bat science - Product and technologies development
We seek to apply the findings of our fundamental research to developing technologies which could be included in the development of products that could eventually be classified as potential reduced-exposure products (PREPs).
Much of the detail of this work is commercially confidential, although on this website we describe the areas we are investigating.
Developing new PREP technologies is challenging and can be divided into two very broad categories:
- overall reduction in the amounts of toxicants generated by the cigarette; and
- selective reduction of a range of smoke constituents after they are generated.
Both strategies may be needed to develop products of the future.
The uses and limitations of filters
Yield reductions - as measured on standardised smoking machines - have been achieved in today’s conventional cigarettes by using, among other things, cigarette filters, filter ventilation and, to some extent, expanded tobacco.
Using different filters enables some toxicants to be selectively removed and is an area of active research for future products.
The traditional cellulose acetate filter reduces overall tar levels but is also effective at removing a proportion of phenolic compounds. Incorporating activated charcoal into the filter reduces some volatile smoke components. The addition of other compounds into filters that may remove some classes of toxicants is being investigated.
But many of the toxicants in cigarette smoke exist in the smoke particles. Their low volatility means that selective removal through use of filter materials is not physically possible.
Conversely, some of the gases in smoke such as carbon monoxide are too volatile for filtration to effect significant reductions. For these constituents we are exploring alternative approaches involving modifications to the materials burnt in the cigarette.
Changes to cigarette paper
Changes in combustion by altering paper characteristics can lead to reductions in some gas phase components such as carbon monoxide. The potential may exist to make other changes to effect reductions in toxicants with similar physical properties.
New approaches to tobacco itself
Most toxicants arise from the burning of tobacco. These have to be targeted by discovering - and then attempting to change - the precursor compounds in the tobacco blend. This is not an easy task and it is being approached from a number of angles.
We are attempting to identify tobaccos with intrinsically lower levels of toxicants by understanding geographical variations in the chemistry of the tobacco leaf and the effects of processing post-harvest.
The use of modern plant biotechnology to produce genetically modified tobacco may also offer some potential to reduce a number of toxicants. A number of toxicants such as the heavy metals and the tobacco specific nitrosamines are present in the tobacco plant and genetic modification may offer new ways of reducing these.
We are also developing novel tobacco processing techniques to potentially reduce the levels of toxicant precursors in tobacco before it goes into the cigarette.
Another approach is the development of additives that can be incorporated into the tobacco blend in order to modify the chemistry of the smoke as the cigarette burns.
Patents
Like all areas of technological development, new and inventive areas of candidate PREP related technology are patentable. Details of some examples of candidate PREP related technology, patented by British American Tobacco, are shown below.
Please note however, that patent applications have to be filed early in the development of the concept to which they relate, before the idea is published in any way, and hopefully ahead of the competition. This means that a concept as described in a patent application is often unproven in many ways - for example in terms of scaled-up manufacture and customer appeal, let alone the research needed to determine whether the impact of the technology will reduce harm.
The patents referred to are, therefore, examples of innovations created in the context of potentially reduced-risk product research and development, and not of innovations with demonstrated harm reduction potential over time.
| Type | Patent | Description |
|---|---|---|
| Filter Material | British American Tobacco Investments International Patent Application No. WO 2005/118133 | A cigarette filter contains an additive comprising gold and a mixed oxide of zinc and aluminium. The additive is a catalyst that oxidises carbon monoxide in tobacco smoke to form the less harmful CO2. |
| Activated Carbon | British American Tobacco Investments International Patent Application No. WO 2006/103404 | Certain activated carbons with a pore volume of at least 0.9 cc/g and a pore structure in which 15-65% of the pore volume is in mesopores (2-50 nm diam.), the rest being in micropores (< 2nm diam.) or macropores (> 50nm) show improved selective adsorption towards HCN and butadiene. |
| Tobacco Substitute | British American Tobacco Investments International Patent Application No. WO 1998/057556 | A smoking mixture with reduced tobacco content is made up of tobacco, an aerosol generator, for example triethylene glycol diacetate, or glycerol di- or triacetate, an inorganic filler material, for example calcium carbonate, and binder for example an alginate. |
| Tobacco Treatment | British American Tobacco Investments International Patent Application No. WO 2001/65954 | Nitrosamines are removed selectively from tobacco by an extraction process using supercritical carbon dioxide at elevated pressure and temperature. |
| Tobacco processing | British American Tobacco Investments & MIP Technologies AB International Patent Application No WO 2005/112670 | Molecularly imprinted polymers that specifically recognise and bind to nitrosamines are prepared by reacting a functional monomer (e.g. methacrylic acid) with a cross-linking agent (e.g. ethylene glycol dimethacrylate) in the presence of a nitrosamine structural analogue material, and then removing the analogue material. The resulting material may be used to extract TSNA’s from tobacco extracts. |
