POLONIUM-210 IN CIGARETTE SMOKE.

Tests of several brands of Indian cigarettes using a smoking simulator device revealed the presence of **2**1**0Po in inhaled smoke. While **2**1**0Po intake by a person smoking 20 cigarettes per day is considerably higher than the quantity inhaled in normal breathing, it amounts to a small fraction of the maximum permissible intake through air of this radionuclide for individuals in population at large. Average annual doses to the pulmonary compartment due to smoking of 20 cigarettes per day with the lung as the critical organ were computed using the model set up by the Task Group on Lung Dynamics of the International Commission on Radiological Protection; the doses range from 2 to 115 millirems/year for different brands.