Determination of Radioactivity concentrations in sediments and Biota of East Bank of River Arvand and Northern Coast of Persian Gulf.
2007
Pur Ahmad Jaktaji, Jalal | Motallebi Moghanjuqi, Abbas Ali | Shah Hosseini, Sorayya | Nikuyan, Ali Reza | U`fi, Fereydun | Eskandari, Gholam Reza | Khalife Nil Saz, Mansur | Reza`i, Mohsen
Gamma-ray spectrometric measurements were performed on sediment samples from the coast of Khuzestan province (south east of Iran, neighbor to Iraq and Kuwait) to study the concentration of natural as well as man-made radioactive sources. The coast of Khuzestan, which extends for some 400km is mainly soft areas of mud flats within different ecosysrems including river mouth, estuaries, creeks and small bays. Suspended material from the Iranian rivers including Arvand (Karun), Bahmanshir, Jarrahi and Zohreh has settled to form these extensive soft areas. Eighty three samples were taken at different points along the coast in undisturbed areas at intervals of about 5 km. Collection was carried out during low-tide, where it was possible to collect sediments from the wet region that was covered by sea water during the high tide. The average activity concentration of the radionuclides 226Ra (30 Bq/Kg), 232Th (11 Bq/Kg), 238U (18 Bq/Kg) and 137Cs (2.6 Bq/Kg) along the shore of Khuzestan reaches are much less than the values commonly assigned as the world average. Nevertheless in case of 40K which is usually considered as the oil pollution finger print, the result (481 Bq/Kg) was higher than world average which could be due to large Kuwaiti oil spill and also fallout and deposition of tremendous amount of fly ashes resulted from ignited Kuwaiti oil fields during the 2nd Persian Gulf war (1990-91). For man-made 137Cs and naturally occurred 232Th, the western and eastern parts of Khuzestan shore showed higher concentrations than the middle part (Khooriat or creeps). For oil pollution finger print radionuclide 40K and Gulf war resulted 238U (anti armor shells), there were no significant differences (P0.05) among the 3 regions.
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