Study On ¹³⁷Cs Pollution In A Biological Sample Around A Nuclear Power Plant

¹³⁷Cs is one of the radioactive isotopes of cesium,with a half-life of 30.17a.Once it enters the environment,it will exist for a long time,and it is one of the radionuclides in the radioactive environment.Under natural environmental conditions,¹³⁷Cs enters the human body mainly through the food chain,and ¹³⁷Cs in the air can also enter the human body through such channels as respiration.The ¹³⁷Cs entering the human body will cause great damage effect on the human body.After entering the human body,it mainly stays in the bones and muscle tissues,which usually leads to soft tissue tumors to cause cancer.The chronic damage to the human body is also manifested in various tissues and organs inflammatory lesions.Human intake of more than 0.25Gy will cause damage to the nervous system and hematopoietic system,abnormal births and even sterilization,and intake of more than 6Gy will kill.Therefore,in terms of the radiation hazard of ¹³⁷Cs to human body,it is necessary to carry out long-term monitoring and control of ¹³⁷Cs content in living organisms.In order to study the degree of influence of the emitted radionuclide¹³⁷Cs on surrounding organisms during the operation of a nuclear power plant,this paper monitored the concentration of ¹³⁷Cs in the organisms around a nuclear power plant from May 2013 to November 2017,analyzed the monitoring data,and studied whether ¹³⁷Cs discharged during the operation of the nuclear power plant would cause harm to the surrounding ecological environment.This paper combines the final measurement data and compares it with the Tianwan Nuclear Power Plant and the national average.Among them,the samples of mutton,green vegetables,radish and rice have a range of（7-34）mBq/Kg,（9-33）mBq/Kg,（3-20）mBq/Kg and（6-13）mBq,respectively,with the average values of 17 mBq/Kg,16 mBq/Kg,13 mBq/Kg and 11 mBq/Kg.The range of ¹³⁷Cs in biological pine needles,oysters and mosses is（5-40）mBq/Kg,（8-12）mBq/Kg and（4-10）mBq/Kg,respectively,the average values are 23 mBq/Kg,10 mBq/Kg and 6mBq/Kg.The monitoring data values of all the samples of the subject were lower than the relevant monitoring data values of the Tianwan Nuclear Power Plant,and the changes of the ¹³⁷Cs content in all organisms were not significant during the five years.Therefore,it can be concluded that during the five years from 2013 to 2017 when the nuclear power plant was in operation,the radionuclide nuclide¹³⁷Cs emitted by the plant had little impact on the surrounding organisms and did not pollute the surrounding organisms.