Last update Nov. 17, 2022



Very unsafe. Contraindicated. Use of an alternative or cessation of breastfeeding. Read the Commentary.

It is a radioisotope of phosphorus that, under its various forms (Phosphorus-32P, Sodium Phosphate 32P and Chromic Phosphate 32P), is used intravenously in the treatment of polycythemia vera, chronic myeloid leukemia, chronic lymphocytic leukemia, bone metastases, malignant effusions and ovarian or prostate carcinoma. It is also used in the diagnosis of tumors. Intra-articular injection has been used in rheumatoid arthritis and other arthropathies. (Martindale)

It is excreted in breast milk. The potential radiation dose for the infant that was measured two days after the maternal administration was less than 180 microSv (18 mrem), therefore less than 1 milliSv. (Mountford 1994) and in another study it was 50 - 60 mrad daily. (Carlson 1983)

If we want to limit exposure to 0 mili Servers (mSv), you should stop breast-feeding for a period equivalent to from 5 to 10 biological half-lives. It is also possible to determine the radioactivity in milk samples.
Since the annual natural background radiation we receive is around 6 mSv (1 mGy, 100 mrad) (ARSAC 2020), for a more conservative approach we should wait just long enough to achieve an infant exposure of less than 1 mSv (0.1 rem, 0,1 rem, 0,17 mGy, 17 mrad).

Given its long elimination half-life, -11 days for Sodium Phosphate P32 and 14 days for Phosphorus P32- (Mountford 1994), an interruption of breastfeeding of 55 to 70 days would be necessary to avoid irradiating the infant, with milk being expressed and discarded in the meantime, thereby which makes it impossible to continue breastfeeding.


We do not have alternatives for Фосфор-32.

Suggestions made at e-lactancia are done by APILAM team of health professionals, and are based on updated scientific publications. It is not intended to replace the relationship you have with your doctor but to compound it. The pharmaceutical industry contraindicates breastfeeding, mistakenly and without scientific reasons, in most of the drug data sheets.

Jose Maria Paricio, Founder & President of APILAM/e-Lactancia

Your contribution is essential for this service to continue to exist. We need the generosity of people like you who believe in the benefits of breastfeeding.

Thank you for helping to protect and promote breastfeeding.

José María Paricio, founder of e-lactancia.

Other names

Фосфор-32 is Sodium phosphate (32P) in Greek.

Is written in other languages:

Фосфор-32 is also known as


Variable Value Unit
Molecular weight 35 daltons
Tmax 2 hours
264 - 343 hours


  1. ARSAC. Administration of Radioactive Substances Advisory Committee. Notes for Guidance on the Clinical Administration of Radiopharmaceuticals and Use of Sealed Radioactive Sources. Section 7 Conception, Pregnancy and Breastfeeding, p. 53-58. ARSAC Support Unit. Centre for Radiation, Chemical and Environmental Hazards. Public Health England. 2020 Consulted on Dec. 4, 2023 Abstract Full text (link to original source) Full text (in our servers)
  2. Mountford PJ, Wells CP, Hall FM, Coakley AJ. Potential radiation dose to a breast-fed infant following administration of sodium 32P-phosphate to the mother. Nucl Med Commun. 1984 Jul;5(7):473-6. Abstract
  3. Carlson JA Jr, Jose B, Sharma SC, Osborne RP. Radioactivity in breast milk after intraperitoneal chromic phosphate for the treatment of early ovarian cancer. Am J Obstet Gynecol. 1983 Dec 1;147(7):840-1. No abstract available. Abstract

Total visits


Help us improve this entry

How to cite this entry

Do you need more information or did not found what you were looking for?

   Write us at

e-lactancia is a resource recommended by El Parto Es Nuestro of Spain

Would you like to recommend the use of e-lactancia? Write to us at corporate mail of APILAM