Studies on the deposition and distribution of catechol from whole cigarette smoke in BC3F1Cum mice

Tritiated catechol has been used to follow the pharmacokinetics and metabolic fate of inhaled catechol in cigarette smoke in $\text{BC3F1}\text{Cum}$ mice. The presence of ³H]catechol in the smoke was verified by silica gel chromatography, high-performance liquid chromatography, and gas chromatography/mass spectrometry. Mice were exposed to 10% ($\text{v}\text{v}$) 2R1 cigarette smoke on the Walton Horizontal Smoking Machine under standard conditions of 35 ml puff volume, 2 sec/puff, 10 puffs/cigarette. The deposition and distribution of inhaled catechol were determined in all internal tissues, urine, and feces. Data showed that clearance was occurring during the 10-min smoke exposure period. Immediately after exposure, over 50% of the radioactivity was found in the blood, with 10% found in the lung, and approximately 12% in the respiratory tract. Over 91% of the inhaled radioactivity was found in the urine 120 min after exposure. Less than 0.5% of the total dose was found in the lung at this time. We conclude that catechol in smoke is rapidly absorbed, redistributed, and excreted from mice exposed to whole cigarette smoke.