The security of medical radioactive sources, both open and sealed, is an important consideration for reducing the risk of an intentional or inadvertent additional radiation dose to the public, according to the principle of keeping any additional radiation dose as low as reasonably achievable. The detection and following radiological investigation of the misuse of iodine-125 (I), a medically used radionuclide, in Germany is described in detail with the aim of sharing experience and raising awareness. The misuse of I shows that the security of I is not guaranteed completely at the present time.

中文翻译：

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医疗放射性同位素的误用：德国的125I标记扑克牌，案例研究。

根据将任何额外的辐射剂量保持在合理可实现的最低水平的原则，医用放射源（无论是敞开的还是密封的）的安全性是减少对公众有意或无意增加辐射剂量的风险的重要考虑因素。为了分享经验和提高认识，详细描述了在德国对医疗用放射性核素碘125（I）的滥用进行的检测和放射学调查。对I的滥用表明，当前不能完全保证I的安全性。