Chemical Place

Sodium Thiosulfate


As a component in hand warmers and other chemical heating pads that produce heat by exothermic crystallization of a super-cooled solution.

​In bacteriological water assessment, as it promotes the survival of coliform organisms by neutralizing residual chlorine.

In the tanning of leather.

​To demonstrate the concept of supercooling in physics classes: Sodium thiosulfate, when heated, dissolves in its own water of crystallisation. This solution can be cooled to room temperature without recrystallisation. When crystallization is induced by the addition of a small seed crystal, the sudden temperature rise can be experienced by touch.

As part of patina recipes for copper alloys.

​Often used in pharmaceutical preparations as an anionic surfactant to aid in dispersion.As an ingredient to table salt, (example: small packets of iodized salt.

Medical Uses:

It has been used as treatment of calciphylaxis in hemodialysis patients with end-stage renal disease. There is apparently an incompletely understood phenomenon whereby this causes severe metabolic acidosis in some patients.

It is used as an antidote to cyanide poisoning.

​Thiosulfate serves as a sulfur donor for the conversion of cyanide to thiocyanate (which can then be safely excreted in the urine), catalyzed by the enzyme rhodanase.

​It is used in the management of extravasations during chemotherapy. Sodium thiosulfate prevents alkylation and tissue destruction by providing a substrate for the alkylating agents that have invaded the subcutaneous tissues. The dose may be 2 ml of 0.17 M (a solution of 4 ml 10% sodium thiosulfate and 6 ml sterile water for injection). It may be instilled subcutaneously into multiple sites using a small-gauge needle. Data are limited on this method with few recommendations.

​In foot baths for prophylaxis of ringworm, and as a topical antifungal agent.

In measuring the volume of extracellular body fluid and the renal glomerular filtration rate

Neutralizing bleach, chlorinated water, and related treatments:

It is used to dechlorinate tap water for myriad purposes notable water treatment plants prior to release into rivers. The reduction reaction is analogous to the iodine reduction reaction. Treatment of tap water lowers chlorine levels for use in aquaria and swimming pools and spas (example: following superchlorination)