The use of high-risk radioactive materials in medical, research, and commercial applications has increased by about 30 percent in the U.S. in the last 12 years, and the government should improve security, tracking, and accountability to reduce health and security risks — while also supporting the development of nonradioactive alternatives to replace them — says a new report from the National Academies of Sciences, Engineering, and Medicine. Radioactive Sources: Applications and Alternative Technologies says the U.S. Nuclear Regulatory Commission’s (NRC) system for categorizing and regulating these radioactive materials fails to adequately protect society, and should be overhauled to take into account the long-term health impacts and socio-economic effects of possible misuse or malicious use — such as a “dirty bomb” scenario.