Phosphorus P-32 (P-32) is the phosphorus isotope whose nucleus consists of 15 protons and 17 neutrons. Phosphorus P-32 is one of the most commonly used research emitters and is the one with the highest energy. Its use in molecular biology has become widespread by the use of specific high-activity nucleotides to mark DNA. Phosphorus P-32 may also be used in phosphorylation reactions. More precisely, it is used in the study of the migration of fertilizers (phosphates) in soils. In the medical field, phosphorus P-32 has been used for the treatment of polyglobulia, but this is increasingly rare. Emitted by phosphorus P-32, beta particles directly damage cellular DNA and, by ionizing intracellular water to produce several types of cytotoxic free radicals and superoxides, indirectly damage intracellular biological macromolecules, resulting in tumor cell death.