1948: Biological Applications of Tracer Elements, Vol. XIII
Organizer: Milislav Demerec
The history of using radioactive atoms as tracers in physical and chemical reactions has a long history, dating back to 1913 when George de Hevesy and Frederic Paneth carried out the first radioactive-tracer experiment at the Vienna Institute of Radium Research. The importance of radioactive tracers (deuterium, tritium and radioactive phosphorous32P) for metabolic studies was clear prior to the Second World War but the isotopes were difficult to make. This changed with the development of nuclear piles and the great effort devoted to nuclear physics and chemistry after the war. The discovery of 14C in 1940 by Martin Kamen (who attended the meeting) and its ready production in nuclear piles was a very important milestone. Demerec recognized that other meetings had been held on tracers but, he claimed, this Symposium would be the first to focus on biological experimentation rather than on the physics and chemistry of making tracers.
Unfortunately, Demerec persisted in printing contributions in alphabetical order of authors, but George de Hevesy's detailed historical paper was presumably the opening contribution (de Hevesy had won the Nobel Prize for Chemistry in 1931). The power of the tracer approach for unraveling biochemical syntheses is illustrated by the presence of two future Nobelists
reporting on the early stages of their research. Melvin Calvin (Chemistry, 1961) had just started using 14C to determine how, during photosynthesis, the carbon of carbon dioxide makes its way into carbohydrates in the plant, while Konrad Bloch (Physiology or Medicine, 1964) described his work on lipid synthesis.
That the world had changed and the Cold War had begun, would have been evident to participants who talked to Martin Kamen. Kamen's political views had made him suspect to government security. In 1944, he was dismissed summarily from the Manhattan project and was forced to testify before the House Un-American Activities Committee. His US passport was withdrawn in 1948, not to be reissued until 1955. In 1995, Kamen was received the Enrico Fermi Medal, nation's oldest prize for achievements in science and technology, from President Clinton.
— Jan A. Witkowski