Detection And Risk Assessment Of Foodborne Radionuclides In Beijing

In order to make up for the empty space in the risk assessment of radionuclides in daily diets,based on the internationally accepted risk analysis paradigm,radionuclide-based biokinetics,combined with human digital models and human radiation dosimetry models,this paper has established an evaluation method for the effective dose of food-borne radionuclides in humans.When the assessment method is quantified,the accumulated equivalent dose of each organ involved in the biodynamic model of the radionuclide is multiplied by the corresponding tissue weight coefficient and accumulated to obtain the ingestion dose coefficient of the radionuclide in the human body.The ingestion dose coefficient combined with food consumption and the content of radionuclides in various foods obtained through testing are cumulatively added according to the type of food,and finally an internal irradiation effective dose caused by ingestion under the corresponding dietary structure is obtained,and complete its risk assessment.Among them,the biodynamic model of different radionuclides in the human body was combineed with the unique characteristics of each radionuclide as far as possible,and comprehensively considered the cumulative absorbed dose and radiation sensitivity of the organ.It should be pointed out that the accumulated equivalent dose and the corresponding tissue weight coefficient for each organ in the biological dynamic model are based on the idea of compartment distribution and one-way catenary structure,then combined with the human body of "No.1 China Digital Man" to finish simulations.Based on ICP-MS,the radionuclide content in high-risk foods in Beijing was detected,and the detection results of the natural radionuclide 238U and 232Th,artificial radionuclides 90Sr in various high-risk foods in Beijing were systematically obtained for the first time.In combination with the established method for evaluating the effective dose of foodborne radionuclides in human body,this paper also completed the monitoring of the risk of radionuclides in daily foods in Beijing.According to the detection results,the risk assessment of radionuclide internal exposure to different age groups in Beijing was completed.Based on the assessment method above,a rapid assessment software RASFRI for the effective dose of food-borne radionuclides was developed based on the client-remote server interaction model using eclipse-4.6.2.The software covers Po-210,Ra-226,U-238,Th-232,Sr-89,Sr-90,I-131,Cs-137,Pu-239,to facilitate the relevant departments for food safety in the timely monitoring of radionuclides and risk management.