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Gallaher Limited Recently, you asked me to prepare some brief notes on our views on the Auerbach/Hammond work with some beagles. I have set down our views on this research , which are partly taken from a memorandum to Mr. Pritchard dated 25th February. I also attach for your information documents H465 , which has been prepared by Dr. Brian Davis, on the implications of the Auerbach work for Harrogate research. Our views are as follows:--
(1) We have had an opportunity of seeing both the Auerbach work and the work
at Battelle North West. Both research groups are using beagles which are made
to inhale fresh whole cigarette smoke. The main difference is that in
Auerbach's dogs a tracheostomy has been carried out and a tube inserted into
the trachea. This means that smoke can be involved directly through the
trachea into the lungs, thus bypassing the mouth and upper part of the trachea.
In contrast, the dogs at Battelle North West have no surgical treatment and are
trained to inhale the smoke from a smoking mask. Given the right animal
handler and a reasonable period of acclimatization (usually about a month) the
dogs appear to inhale the smoke without undue stress and the minimum of
restraint. The only obvious outward evidence of smoking is that they tend to
salivate. Those two contrasting methods are described because ideally most
biological research workers would prefer an animal model which does not resort
to surgery and therefore fairly severe trauma, with the possible risk of
introducing infection into a part of the body adjacent to that under test.
However, even when we bear this in mind, Auerbach's research is undoubtedly a
significant step forward and we have to remember that the control animals also
tolerated a tracheostomy without undue discomfort and trauma and there was no
evidence that these animals showed any signs of pre-cancerous or cancerous
changes.
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 (2) One of the striking features of the Auerbach experiment was that practically every dog which smoked suffered significantly from the effects of the smoke, either in terms of severe irritation and bronchitis, pre-cancerous changes or cancer. This, of course, is a much more extreme situation than in human being where only one in ten heavy smokers get lung cancer and one in five suffer from some form of respiratory infection, often describe as mild bronchitis. We can, therefore, question whether the beagle is in some way untypical of human behaviour and the only reasonable argument against this is that the dogs were given a much more massive dose compared with the human dose and in the case of Auerbach's work, since the smoke bypassed the mouth, which sets as a good trap for certain constituents of the smoke, the dog lung was subjected to a much greater effect from the smoke.
(3) However, in spite of the qualifications in one and two, we believe that
the Auerbach work proves beyond reasonable doubt that fresh whole cigarette
smoke is carcinogenic to dog lungs and therefore it is highly likely that it is
carcinogenic to human lungs. It is obviously impossible to be certain of the
extrapolation from an animal lung to a human lung, but we have to bear in mind
that the anatomy of the dog is relatively close to human anatomy and the type
of tumor found in the dog was the same type as found in heavy smokers.
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To sum up, we are of the opinion that Auerbach's work proves beyond all reasonable doubt the causation of lung cancer by smoke, even though in an ideal situation it would have been preferable to avoid a surgical technique, and to allow the animals to live out their life span. Nevertheless, there are certain short-comings of the experiment and it is easier to see these in hind-sight.
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