A salted bomb is a nuclear weapon designed to function as a radiological weapon by producing larger quantities of radioactive fallout than unsalted nuclear arms. This fallout can render a large area uninhabitable. The term is derived both from the means of their manufacture, which involves the incorporation of additional elements (eg, sodium-23) to a standard atomic weapon, and from the expression "to salt the earth", meaning to render an area uninhabitable for generations. The idea originated with Hungarian-American physicist Leo Szilard, in February 1950. His intent was not to propose that such a weapon be built, but to show that nuclear weapon technology would soon reach the point where it could end human life on Earth.
No intentionally salted bomb has ever been atmospherically tested, and as far as is publicly known, none has ever been built. However, the UK tested a one-kiloton bomb incorporating a small amount of cobalt as an experimental radiochemical tracer at their Tadje testing site in Maralinga range, Australia, on September 14, 1957. The Soviet triple "taiga" nuclear salvo test, as part of the preliminary March 1971 Pechora–Kama Canal project, converted significant amounts of stable cobalt-59 to radioactive cobalt-60 by fusion-generated neutron activation and this product is responsible for about half of the gamma dose measured at the test site in 2011. The experiment was regarded as a failure and was not repeated.
