Dosimetry modeling of cigarette smoking and cadmium body burden

Tobacco smoking may constitute a significant nonoccupational source of exposure to cadmium (Cd). Epidemiological studies found higher levels of Cd in urine in association with cigarette smoking suggesting that smoking might contribute significantly to metal body burden. In this study, a biokinetic model was used to predict renal cortex Cd and urine Cd levels associated with empirically based estimates of exposures to Cd in mainstream cigarette smoke. The biokinetic model predicted that smoking 10 cigarettes/day may elevate renal cortex and urine Cd levels 30-123% above the dietary baseline, depending upon intensity of puffing (International Organization for Standardization (ISO) or Health Canada Intense (HCI) smoking machine regimens). For ISO and HCI regimens, renal cortex Cd was predicted to increase 0.12 and 0.38 μg/g per cigarette smoked, respectively, with corresponding elevations in urine Cd of 0.0023 and 0.0069 μg/g creatinine, respectively. The biokinetic model predicted that HCI regimen smoking rates of 13 - 21 cigarettes/day might raise urine Cd levels by amounts observed in two epidemiological studies of smokers and never smokers (0.09-0.15 μg/g creatinine). Predictions based upon the CDBKM provide further support for plausibility of cigarette smoking contributing to the Cd body burden, which might be detectable as smoking-related increments in urine Cd levels.