Nota: il ministro della Sanità Veronesi fa una intensa campagna contro il fumo, ma non ci dice che qualcuno concima il tabacco da decenni con concimi radioattivi... sarà per la legge sulla Privacy?

Applied Radiation and Isotopes 52 (2000) 23-26
Evaluation of the contribution of smoking to total blood polonium-210 in Saudi population
E.I. Shabana (a), M.A. Abd Elaziz (b), M.N. Al-Arifi (c), A.A. Al-Dhawailie (c), M.M-A. Al-Bokari (a)

a) Institute of Atomic Energy Research, King Abdulaziz City for Science and Technology, PO Box 6086, Riyadh 11442, Saudi Arabia
b) Clinical Pharmacology Department, College of Medicine, Mansoura University, Mansoura, Egypt
c) College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
* Corresponding author. Tel.: +966-1-488-3555; fax: +966-1-481-3887.
E-mail address: eshabana@kacst.edu.sa (E.I. Shabana).

Received 12 April 1999; received in revised form 15 May 1999; accepted 25 May 1999

Articolo.completo.in.formato.PDF

Abstract

A preliminary study of 210Po concentrations in the blood of some smokers and nonsmokers is presented in order to evaluate the contribution of smoking to total blood 210Po in Saudi population. Blood samples were collected from 30 volunteers and analyzed by high resolution a-spectrometry using a radiochemical technique. The technique is based on the separation of polonium from other components of the sample by wet ashing with an HNO3 /H2 O2 oxidizing mixture and spontaneous deposition on a silver disc under the relevant conditions for a-particle counting. The results indicated that a significant fraction (about 30%) of blood 210Po is related to smoking.

(c) 2000 Elsevier Science Ltd. All rights reserved.
www.elsevier.com/locate/apradiso

1. Introduction

Phosphate rocks contain 0.1-0.4 lb of uranium/ton of rock (UNSCEAR, 1988). Natural uranium can substitute for Ca in the phosphate rock structure, and over a period of time, accumulates in the phosphate reserves. Therefore, U and U long-lived decay products (226Ra, 210Pb and 210Po) are present in fertilizers manufactured from phosphate rock (Shreve, 1967). High phosphate fertilizers are used for tobacco farming in industrial countries. Tobacco was found to concentrate 210Po from the soil (Singh and Nilekani, 1976). This radiotoxic isotope is found in the soil and in the tobacco leaves and increases with the repeated application of phosphate fertilizer to the soil (Singh and Nilekani, 1976, Marmorstein, 1986). The higher the phosphate levels in the fertilizer used, the higher the concentration of 210Pb and 210Po in the tobacco leaves. Since the 1960's investigators have reported (Kilthau, 1996) that 210Po and 210Pb are present in the gaseous and particulate phases of tobacco smoke and contribute to cancer risk due to their deposition in the lungs. The nuclides are absorbed into the blood and distributed to the different body organs, thus increasing the local radiation exposure. About 10% of the 210Po of cigarettes was found in the main stream smoke filter and about 18% in the butt (Mussalo-Rauhamaa and Jaakkola, 1985). The released 210Po is much more radiotoxic than the b-emitter 210Pb, and the radiation dose to man has been widely studied because of the high incidence of lung cancer among smokers (Rajewsky and Stahlhofen, 1966; Martell, 1974; Marmorstein, 1986; Gairola et al., 1993). It has been suggested (Marmorstein, 1986) that 210Po which emits a-radiation accounts for many, if not all, cigarette smoke-induced lung cancer. There are different environmental pathways to 210Po intake by man. It has been reported (Kilthau, 1996; Marmorstein, 1986) that the content of other carcinogens in today's tobacco has been greatly reduced by changes in tobacco processing methods and modern cigarette fiters, but have little effect on reducing radioactivity. In addition to smoking, other pathways for 210Po intake may be through diet and/or 222Rn gas inhalation which is naturally released from the ground and building materials into the atmosphere. It has been reported (Little and McGandy, 1966; Bulman et al., 1995) that a significant fraction of the isotope present in food is absorbed into the blood. It is time to renew the study and reporting of the radiation health hazards of tobacco smoking. This article presents a preliminary study, which forms the first ever report on the evaluation of the contribution of smoking to the total blood 210Po in Saudi population.

(...)

4. Conclusion

This preliminary study indicates that in the Saudi population a significant part (about 30%) of 210Po in blood is related to smoking. Its average concentration in smokers was 1.8320.63 pCi/l compared with 1.2920.61 pCi/l for non-smokers. Other environmental factors, such as 222 Rn gas inhalation and dietary factors, may make significant contributions. The values reported here can also serve as a base-line to evaluate concentration found in blood of individuals possibly exposed to high environmental levels of 210Po or its parent isotopes.

References

Bulman, R.A., Ewers, L.W., Matsumoto, K., 1995. Investigation of the potential bioavailability of 210Po in some foodstuffs. Science of Total Environment 173 (174), 151.

Gairola, C.G., Wu, H., Gupta, R.C., Diana, J.N., 1993. The mainstream and sidestream cigarette-smoke induced DNA adducts in C7B1 and DBA mice. Environ. Health Prespect. 99, 253.

Henshaw, D.L., Heyward, K.J., Thomas, J.P., Fews, A.P., 1984. Comparison of the a-activity in the blood of smokers and non-smokers. Nucl. Tracks and Rad. Measurements 8, 453.

Holtzman, R.B., 1960. Some determinations of RaD and RaF concentrations in human bone. Argonne National Laboratory Report, 6199.

Kilthau, G.F., 1996. Cancer risk in relation to radioactivity in tobacco. Radiologic Technology 67, 217.

Little, J.B., McGandy, R.B., 1966. Measurement of 210Po in human blood. Nature 211, 842.

Marmorstein, J., 1986. Lung cancer: is the increasing incidence due to radioactive polonium in cigarettes? . South Med. J. 79, 145.

Martell, E.A., 1974. Radioactivity of tobacco trichomes and soluble cigarette smoke particles. Nature 249, 215.

Mussalo-Rauhamaa, H., Jaakkola, T., 1985. Plutonium-239, 240Pu and 210Po content of tobacco and cigarette smoke. Health Physics 49, 296.

Radford, J.R., Hunt, E.P., Sherry, V.R., 1963. Analysis of teeth and bones of a-emitting elements. Radiation Research 19, 298.

Rajewsky, B., Stahlhofen, W., 1966. Polonium-210 activity in the lungs of cigarette smokers. Nature 209, 1312.

Shaheed, K., Somasundaram, S.S.N., Hameed, P.S., Iyengar, M.A.R., 1997. A study of 210 Po distribution aspects in the reverine ecosystem of Kaveri, Tiruchirappalli, India. Environ. Pollution 95, 371.

Shreve, R.N., 1967. Chemical Process Industries, 3rd ed. McGraw-Hill, New York.

Singh, D.R., Nilekani, S.R., 1976. Measurement of polonium activity in Indian tobacco. Health Physics 31, 393.

UNSCEAR, 1988. United Nations Scientific Committee on the Effects of Atomic Radiation.

Vittum, E.K., Minto, W.L., Fink, R.M., 1950. Biological studies with polonium, radium and plutonium. Natl. Nucl.Energy Ser. Div. VI 3, 8.