D5. Particle of Plutonium in Lung Tissue. The black star in the middle of this picture shows tracks made by alpha rays emitted from a particle of plutonium embedded in the lung tissue of an ape. Alpha rays do not travel very far. They are harmless outside the body, but once inside they can damage more than 10,000 cells within their range. Alpha emitters are among the most deadly of radioactive materials. Radon gas, radium, plutonium, and polonium are alpha emitters. After 1,000 years, the main hazard from irradiated nuclear fuel is due to its long-lived alpha emitters. The tracks in the photograph were made by bursts of alpha-radiation over a 48-hour period. Lawrence Radiation Laboratory, Berkeley, California. 20 September 1982.
These photographs by Robert Del Tredici are protected by copyright and are available for purchase as high-quality digital prints on archival paper or as silver gelatin prints from bdeltredici@hotmail.com.