Measurement of 137Cs in soils of Tehran province

Background: an amount of artificial radionuclidehas been released into the environment as fallout,resulting from atmospheric nuclear weapon tests,nuclear accidents such as chernobyl and togetherwith air currents have polluted the world. materialsand methods: 37 surface soil samples of tehranprovince were collected in the period between juneand september 2008, by implementing methods andstandard instruments. the concentration of theartificial radionuclides (137cs) in the soils of tehranprovince were determined by gamma spectroscopy(hpge), and the data were analyzed both quantitativelyand qualitatively. the results have beencompared with other radioactivity measurements.results: the concentration of 137cs found in top soils(0-5 cm), in the depth of (12.5-17.5 cm) and in thedepth of (27.5- 32.5 cm), ranged from 0.29-28.82bq.kg-1, 0.3-19.81 bq.kg-1, 0.8-7.43 bq.kg-1,respectively. the total average of 137cs activity, in theabove depths was, 11.30, 4.87 and 1.8 bq.kg-1,respectively. conclusion: considering the obtainedresults from high average values of 137cs in europeand its relation to chernobyl accident, and the higheraverage concentration of 137cs in tehran province,can also be attributed to chernobyl accident due tothe proximity of iran to the place of the accident'soccurrence.