P-32 is a radioactive isotope of phosphorus with a half-life of 14.29 days. Radioactive decay of P-32 produces beta-particles (electrons) which are able to penetrate tissue at a range of 3-8 mm. Phosphate ion P-32 has many applications in medicine and biology. P32 sodium phosphate was approved by the FDA for the treatment of polycythemia vera, chronic myelocytic leukemia, and chronic lymphocytic leukemia. P32-phosphate may also be used in the palliative treatment of selected patients with multiple areas of skeletal metastases. As metabolic uptake of phosphorus is selectively increased in malignant tissues, P-32 was also used for cancer diagnostics.