اندازه گيري پرتوزايي خاك هاي سطحي شرق نيروگاه سوخت فسيلي شازند

Measurement of Radioactivity of Surface Soil in the East of Shazand Power Plant

زﻣﯿﻨﻪ و ﻫﺪف: اﻧﺴﺎن ﻫﺎ ﻫﻤﻮاره در ﻣﻌﺮض ﭘﺮﺗﻮﻫﺎي ﯾﻮنﺳﺎز ﻗﺮار دارﻧﺪ. ﯾﮑﯽ از ﻣﻨﺎﺑﻊ اﯾﻦ ﭘﺮﺗﻮﻫﺎ، ﺗﺎﺑﺶﻫﺎي ﻫﺴﺘﻪاي ﻣﺮﺑﻮط ﺑﻪ وﯾﮋه ﻫﺴﺘﻪﻫﺎي ﭘﺮﺗﻮزاي ﻣﻮﺟﻮد در آب، ﺧﺎك، ﺳﻨﮓ و ﮔﯿﺎﻫﺎن اﺳﺖ. ﻋﻨﺎﺻﺮ ﭘﺮﺗﻮزا ﺑﺎﮔﺴﯿﻞ ﺗﺎﺑﺶﻫﺎي ﻫﺴﺘﻪاي ﺑﺎﻋﺚ ﺑﺮوز ﺑﯿﻤﺎريﻫﺎﯾﯽ ﻧﻈﯿﺮ ﺳﺮﻃﺎن و ﻧﺎﻫﻨﺠﺎريﻫﺎي ژﻧﺘﯿﮑﯽ ﻣﯿ ﮕﺮدﻧﺪ. ﺑﻨﺎﺑﺮاﯾﻦ ﻣﻄﺎﻟﻌﻪ و ﺑﺮرﺳﯽ ﭘﺮﺗﻮزاﯾﯽ ﺧﺎك از اﻫﻤﯿﺖ زﯾﺎدي ﺑﺮﺧﻮردار اﺳﺖ. روش ﺑﺮرﺳﯽ: در اﯾﻦ ﭘﮋوﻫﺶ34 ﻧﻤﻮﻧﻪ ﺧﺎك از ﺣﺪﻓﺎﺻﻞ ﻧﯿﺮوﮔﺎه ﺳﻮﺧﺖ ﻓﺴﯿﻠﯽ ﺷﺎزﻧﺪ ﺗﺎ ﺷﻬﺮ اراك ﻣﻮرد ﻣﻄﺎﻟﻌﻪ ﻗـﺮار ﮔﺮﻓـﺖ. ﻓﻌﺎﻟﯿـﺖ وﯾـﮋه ﻫﺴﺘﻪﻫﺎي ﭘﺮﺗﻮزا از روش ﺑﯿﻨﺎبﻧﮕﺎري ﮔﺎﻣﺎ و ﺑﺎ اﺳﺘﻔﺎده از آﺷﮑﺎرﺳﺎز ﻓﻮق ﺧﺎﻟﺺ ژرﻣﺎﻧﯿﻮﻣﯽ )HPGe( ﺑﺎ ﺑـﺎزدﻫﯽ ﻧﺴـﺒﯽ 30% ﺗﻌﯿـﯿﻦ ﮔﺮدﯾـﺪ. ﻣﻘﺎدﯾﺮ ﻓﻌﺎﻟﯿﺖ وﯾﮋه ﻋﻨﺎﺻﺮ ﭘﺮﺗﻮزا، ﻓﻌﺎﻟﯿﺖ ﻣﻌﺎدل رادﯾﻢ و آﻫﻨﮓ دز ﺟﺬﺑﯽ در ﻫﻮا ﺑﺮاي ﮐﻠﯿﻪ ﻧﻤﻮﻧﻪﻫﺎ ﻣﺤﺎﺳﺒﻪ ﺷﺪ. ﯾﺎﻓﺘﻪﻫﺎ: ﻣﻘﺪار ﻓﻌﺎﻟﯿﺖ وﯾﮋه ﻫﺴﺘﻪﻫﺎي ﭘﺮﺗﻮزاي 226Ra و 232Thو 40K و 137Cs درﻧﻤﻮﻧﻪﻫﺎي ﺟﻤﻊآوري ﺷﺪه ﺑﻪ ﺗﺮﺗﯿﺐ درﻣﺤﺪوده 18/92±1/91ﺗﺎ 43/11±2/69 و 25/31±2/16 ﺗﺎ 54/27±3/65 و 230/17±9/96 ﺗﺎ728/25±18/03 و 1/49< ﺗﺎ 9/52±0/88ﺑﺮﺣﺴﺐ ﺑﮑﺮل ﺑﺮﮐﯿﻠﻮﮔﺮم ﺗﻐﯿﯿﺮ ﻣﯽﮐﻨﺪ. ﻣﻘﺪار آﻫﻨﮓ دز ﺟﺬﺑﯽ در ﻫﻮا در ارﺗﻔﺎع ﯾﮏ ﻣﺘﺮي و ﻓﻌﺎﻟﯿﺖ ﻣﻌﺎدل رادﯾﻮم ﺑﻪ ﺗﺮﺗﯿﺐ از 40/57±1/38 ﺗﺎ

Background and Objective: Human beings are always exposed to ionizing radiation. One of the sources of this radiation is the nuclear radiation from terrestrial radioactive nuclide in water, soil, rock and plants. Nuclear radiation emission from radionuclides causes diseases like cancer and genetic abnormalities. Therefore, studies of soil radioactivity are of great importance. Method: In this research, 34 soil samples were studied between the Shazand Power Plant and Arak city. The specific activities radionuclides were determined using gamma ray spectrometry method, with employing a high purity germanium detector (HPGe) model GCD30195 with 30% relative efficiency. Finding: The specific activity of 226Ra, 232Th, 40K and 137Cs in these samples varied from 18.92± 1.91 to 43.11± 2.69, 25.31± 2.16 to 54.27±3.65, 230.17±9.96 to728.25± 18.03 and <1.49 to 9.52±0.88 in Bq/kg respectively. Absorbed dose rate in air one meter height from ground and radium equivalent were calculated as 4.57± 1.38 to 79.68 ±2.07 in nGy/h and 84.14± 3.08 to 157.74± 4.50. Conclusion: The average of radium equivalent for soil samples was calculated as 116.38±18.38 Bq/kg which is the same level of world average (131.69). Maximum radioactivity observed in 3 to 7 km distance from Power Plant. The results of this study indicate that the radiation of the soil does not pose a threat to the health of the inhabitants.