Hevesy, Georg Karl von (1885–1966)

Hungarian-born Swedish chemist, discoverer of the element hafnium. He was awarded the Nobel Prize for Chemistry in 1943 for his use of a radioactive isotope (see radioactivity) to follow the steps of a biological process.

Hevesy was born in Budapest and educated in Germany, Switzerland, and the UK, studying at Manchester under nuclear physics pioneer Ernest Rutherford in 1911. He worked in Copenhagen at the Institute of Physics under Niels Bohr 1920–26 and 1934–43. During the German occupation of Denmark in World War II, Hevesy escaped to Sweden and became professor at Stockholm.

Hevesy first used radioactive tracers to study the chemistry of lead and bismuth salts. During the early 1930s, he began experiments with this technique on biological specimens, noting the take-up of radioactive lead by plants, and going on to use an isotope to trace the movement of phosphorus in the tissues of the human body. He used heavy water to study the mechanism of water exchange between goldfish and their surroundings and also within the human body. Using radioactive calcium to label families of mice, he showed that, of calcium atoms present at birth, about 1 in 300 are passed on to the next generation.