[9][10] The Manhattan Project began shortly after the discovery, with most early research (pre-1944) carried out using small samples manufactured using the large cyclotrons at the Berkeley Rad Lab and Washington University in St.

Both uranium and plutonium were eventually determined to be fissile, but in each case they had to be purified to select for the isotopes suitable for an atomic bomb.

"[11] By his request, the Rad Lab at Berkeley made available 1.2 mg of plutonium by the end of October 1943, most of which was taken to Los Alamos for theoretical work there.

However, this plutonium was mixed with large amounts of uranium fuel and destined for the nearby chemical processing pilot plant for isotopic separation (enrichment).

[12] Plutonium handling mishaps occurred in 1944, causing alarm in the Manhattan Project leadership as contamination inside and outside the laboratories was becoming an issue.

[12] In August 1944, chemist Donald Mastick was sprayed in the face with a solution of plutonium chloride, causing him to accidentally swallow some.

In a memo to Robert Stone at the Chicago Met Lab, Seaborg wrote "that a program to trace the course of plutonium in the body be initiated as soon as possible ... [with] the very highest priority.

[12] Albert Stevens, after a (mistaken) terminal cancer diagnosis which seemed to include many organs, was injected in 1945 with plutonium without his informed consent.

[17][12] The fact that he had the highly radioactive plutonium-238 (produced in the 60-inch cyclotron at the Crocker Laboratory by deuteron bombardment of natural uranium)[17] contributed heavily to his long-term dose.

R. T. Carpenter had chosen 238Pu as the fuel for the first RTG (radioisotope thermoelectric generator) to be launched into space as auxiliary power for the Transit IV Navy navigational satellite.

[20] This made available the excess Savannah River 238Pu production for Space Electric Power use just in time to meet the needs of the SNAP-27 RTG on the Moon, the Pioneer spacecraft, the Viking Mars landers, more Transit Navy navigation satellites (precursor to today's GPS) and two Voyager spacecraft, for which all of the 238Pu heat sources were fabricated at Mound Laboratories.

[22] An addition to the Special Metallurgical building weapon component production facility was completed at the end of 1964 for 238Pu heat source fuel fabrication.

[23] In the United States, when plutonium-238 became available for non-military uses, numerous applications were proposed and tested, including the cardiac pacemaker program that began on June 1, 1966, in conjunction with NUMEC.

[27] In a letter to the New England Journal of Medicine discussing a woman who received a Numec NU-5 decades ago that is continuously operating, despite an original $5,000 price tag equivalent to $23,000 in 2007 dollars, the follow-up costs have been about $19,000 compared with $55,000 for a battery-powered pacemaker.

Via agreement with Minatom, the US must use plutonium for uncrewed NASA missions, and Russia must use the currency for environmental and social investment in the Chelyabinsk region, affected by long-term radioactive contamination such as the Kyshtym disaster.

[39][40] In February 2013, a small amount of 238Pu was successfully produced by Oak Ridge's High Flux Isotope Reactor,[41] and on December 22, 2015, they reported the production of 50 grams (1.8 ounces) of 238Pu.

[42][43] In March 2017, Ontario Power Generation (OPG) and its venture arm, Canadian Nuclear Partners, announced plans to produce 238Pu as a second source for NASA.

Rods containing neptunium-237[44] will be fabricated by Pacific Northwest National Laboratory (PNNL) in Washington State and shipped to OPG's Darlington Nuclear Generating Station in Clarington, Ontario, Canada where they will be irradiated with neutrons inside the reactor's core to produce 238Pu.

[45][46] In January 2019, it was reported that some automated aspects of its production were implemented at Oak Ridge National Laboratory in Tennessee, that are expected to triple the number of plutonium pellets produced each week.

The RTG was invented in 1954 by Mound scientists Ken Jordan and John Birden, who were inducted into the National Inventors Hall of Fame in 2013.

[50] RTG technology was first developed by Los Alamos National Laboratory during the 1960s and 1970s to provide radioisotope thermoelectric generator power for cardiac pacemakers.