NICOTINE OR TAR TITRATION IN CIGARETTE-SMOKING BEHAVIOR

A significant problem in assessing the relative relevance of nicotine and tar yield for compensatory smoking after switching from high to lo w yield cigarettes is that nicotine and tar yield are highly intercorr elated across conventional cigarettes and that the tar/nicotine ratios vary only within a modest range. A better differentiation between the impacts of nicotine and tar yield was expected by comparing in a labo ratory experiment a new low nicotine/medium tar cigarette (''Next'') w ith conventional low nicotine/low tar (ultra-light) cigarettes and wit h medium nicotine/medium tar cigarettes with respect to nicotine absor ption and physiological effects. Twelve females, habitually smoking me dium type cigarettes (greater-than-or-equal-to 0.7 mg nicotine) partic ipated in the study. Neither the number of cigarettes smoked under fie ld conditions nor the puffing behavior during the laboratory experimen t differed between the three types of cigarettes. In the laboratory, N ext produced only very small increases in plasma nicotine and changes in cardiovascular or EEG measures, whereas the effects of the medium c igarettes were in the expected range and those of the ultra-light ciga rettes about halfway in between. The nicotine absorption/nicotine yiel d and the CO absorption/CO yield ratios were similar for Next and the habitual cigarettes, but about twofold higher for the ultra-light ciga rettes. This suggests that gustatory and olfactory sensations, which a re supposed to be more dependent on tar than on nicotine yield, may pl ay a greater role for the regulation of smoking behavior than hitherto believed.