Borax
Arabic bawraq; tincal
- Known today as
- Sodium borate, brought as the crude salt tincal from the lakes of Tibet.
- Kind
- Mineral
- Constituents
- sodium tetraborate, boric acid
- In other databases
- Wikidata search
Caution. Poisonous to children in quantity.
Borax: what was it used for?
A flux for goldsmiths; in medicine, mixed with honey as a paint for thrush in the mouths of infants.
Borax: what does modern science say?
Toxic in quantity, particularly to children; its use in medicines for the mouth has been abandoned, and the European Union counts it harmful to reproduction.
Borax: is it poisonous?
Yes, in some form or dose. Poisonous to children in quantity. Historical description, not medical advice; in a poisoning, call a poison centre.
Pharmacognosy & Toxicology
- Constituents
- Mechanism
- Boron compounds are cumulative poisons of the testes and the developing child in animals; in infants, boric acid absorbed through broken skin has killed.
- Toxic dose
- About 15–20 g of boric acid for an adult; far less for an infant.
- Standing
- Classed as toxic to reproduction in the European Union; boric acid eye washes survive at low strength.
- European Chemicals Agency (2010). Harmonised classification of boric acid and borates. Book, not indexed
Constituent names open the compound’s record at PubChem, and “ChEMBL” beside a name opens its record at ChEMBL, the European Bioinformatics Institute’s database of bioactive molecules. Where a mechanism line was checked against ChEMBL (ChEMBL 37, read 1 October 2026), the check is shown with the measured value and its source paper, or says plainly that nothing has been measured. Doses are as the references give them, for description only; this is not medical advice. Each source carries the result of its check against Crossref, PubMed, or the authority’s page: see Verification.
In Their Own Words
The 1911 Britannica says the Tibetan borax deposits were known from very early times, and that the crude material was exported to Europe under the name of tincal.
“The Tibetan mineral deposits have been known since very early times, and formerly the crude material was exported to Europe, under the name of tincal, for the preparation of pure borax and other boron salts.”
Encyclopædia Britannica, eleventh edition: Borax, “Borax”, Mineralogy. The 1911 Encyclopædia Britannica, as transcribed on Wikisource. The text, read in full
Culpeper notes that borax is used to solder gold, silver and copper, and says that given inwardly in small quantities it stops fluxes and the running of the reins.
“…besides the virtues it has to solder Gold, Silver, Copper, &c. inwardly given in small quantities, it stops fluxes, and the running of the reins”
Nicholas Culpeper, M.D., The Complete Herbal ... to which are now first annexed, the English Physician Enlarged, and Key to Physic, Catalogue of Simples in the New Dispensatory: Gums, Rozins, Balsams. A new edition. London: Thomas Kelly, 17, Paternoster Row, MDCCCL (Project Gutenberg eBook #49513). The text, read in part
Each passage is quoted from the text named, which the press fetched and read, and was checked word for word against a fresh copy of it; the link opens that copy. Passages are given as printed, without the editors’ footnote numbers, and with words broken across lines joined.
Sources
- Pomet, P. (1694). Histoire générale des drogues (English, A Compleat History of Druggs, 1712). Read in part · the text read
Verification
- Checked
- October 1, 2026
- Passes
- Every sentence read against its sources, in the pass over the remaining 343 entries
- The Standing line checked against the authority it names (EMA, WHO, FDA, CITES, Commission E)
- Every dated or regulatory claim checked by category across the database
- Sources
- 2 cited: 1 read in part, 1 book, not indexed.
- Corrections
- None were needed.
What was checked, how, and what was found is set out on the Verification page. A checked source is one whose record was found; it does not make the entry medical advice.
Cite This Entry
Version 1 · first published September 30, 2026
- Chicago
“Borax.” In Materia Medica, edited by B. C. P. Statema. Version 1. The Thinking Press, 2026–. Last modified September 30, 2026. https://thethinkingpress.org/materia-medica/borax.
- MLA
“Borax.” Materia Medica, edited by B. C. P. Statema, version 1, The Thinking Press, 30 Sept. 2026, thethinkingpress.org/materia-medica/borax. Accessed 8 Oct. 2026.
- APA
Borax. (2026, September 30). In B. C. P. Statema (Ed.), Materia medica (Version 1). The Thinking Press. Retrieved October 8, 2026, from https://thethinkingpress.org/materia-medica/borax
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See Also
Drawing on the same sources: Pomet
Nearby in the alphabet
Breve (A written prayer or holy names folded and worn on the body) · Borage (Borago officinalis) · Brewer’s yeast (beer, and wine) · Bogbean · Broom (Spartium junceum, or common broom, Cytisus scoparius) · Bloodstone (iron oxide, which streaks blood-red) · Brown roll-rim (of birch woods) · Bloodroot (the first flower of the spring woods from Canada to the South)
Historical description, not medical advice.