Contamination of Bikini Lagoon by the Baker shot of Operation Crossroads, Bikini Atoll, July 25, 1946.  A radioactive puffy surgeon fish takes its own x-ray (fish was placed on photographic film overnight).  Brightest area is the stomach filled with fresh algae.  The rest of the body has absorbed and distributed enough fission product radioactivity to make the entire fish radioactive.  The fish was alive and apparently healthy when caught.
Anonymous military photographer
1946
Joint Task Force One, <i>Operation Crossroads: the Official Pictorial Record</i>, 1946, p 216.