Abstract Introduction In nuclear and radiological accidents there is a risk of radioactive contamination and accidental intake of radionuclides. Therefore, the individual monitoring of internal exposures is essential for the prompt response to an emergency situation. Individual monitoring allows classifying and evaluating the accident, preventing the increase of contaminated areas and number of affected people and assessing the efficacy of the remediation actions and the decontamination procedures. This study evaluated the use of gamma cameras for individual monitoring of photon-emitting radionuclides incorporated into the human body based on urine samples to apply as a prompt response in emergency situations. Methods For this, a gamma camera available in a military public hospital located in the city of Rio the Janeiro was calibrated using standard liquid sources of 57Co, 22Na, 137Cs and 54Mn supplied by the National Laboratory of Metrology (LMNRI) of the Institute of Radiation Protection and Dosimetry (IRD), all in a 1 L bottle geometry, simulating an urine bioassay. “Efficiency vs Energy” curves at 5, 10, 15 and 20 cm source-to-detector distances were obtained. Based on the “Efficiency vs Energy” curves Minimum Detectable Activities, Minimum Detectable Intakes and Minimum detectable committed effective dose were calculated for 106Ru, 103Ru, 131I, 134Cs and 137Cs at the four source-to-detector distances. Results The results showed that the gamma camera presents Minimum detectable committed effective dose bellow 1 mSv for 103Ru, 131I, 134Cs and137Cs. For 106Ru the Minimum detectable committed effective dose calculated ranged from 1.84 to 3.40 mSv, which is acceptable in emergency situations. Conclusions It has been concluded that the equipment evaluated in this work shows enough sensitivity for use as screening method in accident situations involving intakes of such radionuclides.

中文翻译：

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在紧急情况下使用伽马照相机根据尿样单独监测发射光子的放射性核素

摘要 引言 在核事故和放射性事故中，存在放射性污染和意外摄入放射性核素的风险。因此，对内照射进行个体监测对于迅速响应紧急情况至关重要。个人监测可以对事故进行分类和评估，防止污染区域和受影响人数的增加，并评估补救措施和净化程序的有效性。本研究评估了伽马相机在个人监测中基于尿液样本纳入人体的发射光子的放射性核素的用途，以便在紧急情况下迅速做出反应。为此，位于里约热内卢市的一家军事公立医院提供的伽马相机使用辐射防护和剂量学研究所国家计量实验室 (LMNRI) 提供的 57Co、22Na、137Cs 和 54Mn 标准液体源进行校准（ IRD)，全部​​装在 1 L 瓶几何形状中，模拟尿液生物测定。获得了 5、10、15 和 20 厘米源到探测器距离处的“效率与能量”曲线。根据“效率与能量”曲线，计算了 106Ru、103Ru、131I、134Cs 和 137Cs 在四个源到探测器距离处的最小可探测活动、最小可探测摄入量和最小可探测有效剂量。结果 结果表明，伽马相机对 103Ru、131I、134Cs 和 137Cs 的最小可检测待积有效剂量低于 1 mSv。对于 106Ru，计算的最小可检测待积有效剂量范围为 1.84 到 3.40 毫希，这在紧急情况下是可以接受的。结论 已经得出的结论是，这项工作中评估的设备显示出足够的灵敏度，可用作涉及摄入此类放射性核素的事故情况下的筛查方法。