CIGARETTE SMOKE

Te Awamutu Courier, Volume 56, Issue 4043, 4 May 1938, Page 3

CIGARETTE SMOKE

INVESTIGATIONS BY SCIENTISTS. Reference was made recently to a contrivance called, by its inventors, a “robot” cigarette smoker. This robot was an apparatus designed for use in an investigation entailing the analysis of cigarette smoke. Simulating the ordinary method of smoking, the apparatus could make so many “puffs” a' minute, each puff being of so many seconds’ duration. Each factor—that is, number and duration of puffs was capable of being varied at will between certain limits, and the strength, of the puff and the amount of air drawn through in a given time were variable. In other words, the apparatus could give a standardised method of smoking, a method free from the idosyncrasies and irregularities of an individual smoker. Such a standardised method when applied to cigarettes of the same batch of tobacco should give consistent results; the composition of the smoke from one cigarette should agree reasonably closely with that from any other. The ultimate objective of the investigation was not so much to obtain reliable and reproducible figures concerning the composition of the smoke as to gain facts and figures which might be used in assessing more accurately than hitherto the meaning of such terms as flavour, taste, and other physiological effects produced by smoking. The work is a typical example of many of the technical investigations of to-day which aim at supplying a manufacturer with useful facts and figures, and to this extent freeing him from having to rely on rule-of-thumb methods for the carrying-out of a process. Every manufacturer aims at turning out something which is of uniform standard, if for no other reason than that the public expects to be able to buy such. The extent to which this standardisation can be achieved is dependent largely on the extent to which the raw materials used in manufacture are themselves of standard quality. Now, in this matter, the tobacco manufacturer, as with many other manufacturers, is at a distinct disadvantage, since his raw material is of vegetable origin, dependent on crops

subject to seasonal and other variations. Not only do different countries produce different types of tobacco—every smoker knows th difference betwen Virginian and Turkish but even in the same region the quality of any one type varies with differences of soil, cultivation, curing, and so on. The cigarette maker tries to smooth out these variations, and experience has taught him how to assess them so that he can market a reasonably even grade of product by careful blending. His efforts, however, are still subject to the verdict of the smoking public, which expresses its views in terms of flavour, taste, &c., terms of somewhat capricious meaning, and unscientific in that they are not measurable. What is needed is a more exact correlation between the physiological effects and the composition of the inhaled smoke. Fortunately, an analysis of smoke can be made with a fair degree of accuracy, and it is hoped that when sufficient data have been collected grading and blending will be amenable to a more exact treatment.

When organic matter is heated m absence of, or with a limited supply of air, as is tobacco just behind the glowing portion of a cigarette, it undergoes a process known as destructive distillation—that is, it is decomposed, and some of the products formed escapes as vapors and gases. On cooling to air temperature, the gases remain as such, but the heavier vapours condense, partly, at least, to liquid droplets, producing a mist. In the case of tobacco, the permanent gases contain carbon dioxide, carbon monoxide, and apparently sometimes small amounts of sulphuretted hydrogen and prussic acid, while the condensable vapors contain acidic material such as acetic and formic acids, and alkaline material, bases of the type of aniline ammonia and nicotine. Alcohols and aldehydes are also present.

With such a number of substances it might be thought it would be idle to eject any exact concordance of taste with composition, but the question can, fortunately, it seems, be narrowed down considerably. It appeals that taste is, to a large extent, a question of the relative proportions of acidic to basic constituents in the smoke—a “good” tobacco yields a decidedly acid smoke, while a smoke which is excessively basic is harsh and irritating. As in many questions affecting taste and smell, a judicious balancing between nice and nasty seems to be the desideratum. Further, it seems that the acidic constituents are the more

readily absorbed in the mouth, the exhaled being more alkaline than the inhaled smoke.

Other factors have, of course, to be taken into consideration, and the question of the content of nicotine in the tobacco and in the smoke calls for special mention. The percentage of nicotine in tobaccos varies from about 1 to 3 per cent, and the general belief is that tobaccos containing a high percentags are “strong.” This belief is apparently ill-founded; in any case the word is too indefinite in meaning and smokers’ opinions are often in disagreement. Some smokers regard Levantine cigarettes as being stronger than Virginian, but the latter tobacco contains roughly twice the percentage of Nicotine.

Nicotine is an oily substance, freely soluble in water, and boiling at 250 degrees Centigrade. Its poisonous nature is well known. During the operation of smoking a fair proportion of the meeting in the leaf distils unchanged, and of this amount some, with steam and other vapours, condenses as it cools, and is retained in the butt, while some, of course, enters the mouth possibly 10 per cent. Ox the total in the tobacco.

Considering the nature of nicotine, it fc interesting to ascertain how this amount will vary with the manner of smoking. It is found that the amount is much greater when the volume anti duration of puff is increased. Thus, by increasing the amount of indrawn air in the ratios 10, 15, 20, the amounts of nicotine in the smoke arc increased in the ratios 117, 223, 280.

Incidentally, such figures illustrate the necessity of adopting a standardised method of smoking if uniformity in results is to be expected. As mentioned above, butts retain some of the distilled nicotine, and experiments show that they are richer than the original tobacco. Hence the wellknown advice, “Don’t Smoke Butts.”