PUFF-BY-PUFF DETERMINATION OF THE pH OF WATER-EXTRACTABLES FROM MAINSTREAM PARTICULATE PHASE AND WHOLE MAINSTREAM SMOKE OF REFERENCE AND COMMERCIAL CIGARETTES

Abstract Two methods used for a puff-by-puff determination of the pH of water-extractables of cigarette smoke were compared. Particulate and whole smoke data for Kentucky Reference Cigarettes 1R3F, 1R4F, and 1R5F and for a commercial cigarette brand were collected. Mainstream particulate for each puff was collected separately on glass-fiber filter pads. The pads were extracted with deionized water (particulate method) or deionized water purged with exhaust from the smoking machine (whole smoke method) and the pH was measured. Particulate-method pH was inversely related to the amount of particulate collected, allowing for true comparisons between individual puffs from the same cigarette and between cigarette types. The whole smoke method lacked the sensitivity to distinguish between samples and is of little use as a comparative tool, probably because of the large contribution of carbon dioxide.