A Study of Natural Radioactivity and Gamma Radiation Hazard in Tobacco Leaves and Cigarettes in Oyo State, Nigeria
F. C. Akinyose, P.Tchokossa, M. M. Orosun, S. O. Oluyide, O. Olatunji, and G. Martins (pp. 147-157)
Abstract
A study of natural radioactivity on tobacco was studied in order to assess the natural radioactivity content and the gamma radiation hazard in locally produced tobacco leaves and cigarette product in Oyo State, Nigeria, using a well-calibrated Canberra NaI(Tl. The leaves were gotten from two farms known to be two of the major suppliers of the leaves to the dominant tobacco company in Nigeria, and the products were gotten from the market. The radionuclides detected and quantified in this study came from the naturally occurring 238U and 232Th decay series, as well as nonseries 40K. The overall average values of the activity concentration due to 40K, 238U, and 232Th were 57.51, 24.03, and 14.57 Bq kg− , 1 respectively, for tobacco leaves and 48.37, 17.52, and 12.39Bq kg−1, respectively, for cigarette products. Also, the mean external radiation hazard index (Hext) was 0.13 and 0.11 for leaves and cigarette samples, respectively, while the mean internal radiation hazard index (Hint) was 0.20 and 0.15 for the two samples. The estimated values of these radiation indices were less than unity, and this implies that the health risk due to these radionuclides and their short-lived progenies are negligible.