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FOOTNOTE: *Uranium 235 (U-235) and plutonium 239 (Pu-239) are the radioactive elements used in atom bombs. Uranium enrichment is the process by which the concentration of U-235 in natural uranium is increased, eventually to weapons-grade material. From 33 to 55 lbs. of U-235 at roughly 93% purity can be used in a Hiroshima-size bomb. Reprocessing is the chemical procedure for extracting Pu-239 from the spent uranium fuel of nuclear reactors, where the plutonium is produced as a waste product. A breeder reactor uses plutonium as fuel rather than uranium: by atomic fission, additional uranium placed in the breeder is converted into more plutonium than was consumed in the original reaction.
FOOTNOTE: *France and China have not signed, on the grounds that the treaty is inherently discriminatory against nonweapons states.