Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Sodium methanethiolate (CAS No. 5188-07-8) is the sodium salt of methanethiol (CAS No. 74-93-1) and is safer and easier to handle. Upon addition to water, sodium methanethiolate dissociates to the methanethiolate anion and sodium cation. Depending on pH, equilibrium then exists between the methanethiolate anion and methanethiol itself (protonated, neutral form). At environmentally relevant pHs, the substance exists almost entirely in the protonated form, methanethiol. Because the compounds are identical at environmental and biological pH values, toxicity and fate data from either compound can be used to read across to the other compound.