²¹⁰Po and ²¹⁰Pb Activity Concentrations in Cigarettes Produced in Vietnam and Their Estimated Dose Contribution Due to Smoking

Abstract

Smoking cigarettes contributes significantly to the increase of radiation in human body because 210 Po and 210 Pb exist relatively high in tobacco leaves. Therefore, these two radioisotopes in eighteen of the most frequently sold cigarette brands produced in Vietnam were examined in this study. 210 Po was determined by alpha spectroscopy using a passivated implanted planar silicon (PIPS) detector after a procedure including radiochemical separation and spontaneous deposition of polonium on a copper disc (the deposition efficiency of 210 Po on a copper disc was approximately 94%). Sequentially, 210 Pb was determined through the ingrowth of 210 Po after storing the sample solutions for approximately six months. The activity concentrations of 210 Po in cigarettes ranged from 13.8 to 82.6mBq/cigarette (the mean value was 26.4mBq/cigarette) and the activity concentrations of 210 Pb in cigarettes ranged from 13.9 to 78.8mBq/cigarette (the mean value was 25.8mBq/cigarette). The annual committed effective dose for smokers who smoke one pack per day was also estimated to be 295.4µSv/year (223.0µSv/year and 72.4µSv/year from 210 Po and 210 Pb, respectively). These indicated that smoking increased the risk of developing lung cancer was approximately 60 times greater for smokers than for non-smokers.