Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 253-523-3 | CAS number: 37482-11-4
Toxicity to microorganisms
Administrative data
Link to relevant study record(s)
Description of key information
The 17-h EC50 value and the 17-h EC10 value are 160.2 mg/L and 76.9 mg/L, respectively in microorganisms (P. putida)
Key value for chemical safety assessment
Additional information
No data on aquatic toxicity is available for sodium 2 -mercaptoethanolate (target chemical). Read across can however be made to 2- mecaptoethanol (CAS 60 -24 -2). The (sodium) 2-mercapthoethanolate ion is a conjugated base, the read across substance 2-mercaptoethanol its undissociated acid. With a pKa value of ca. 9.5 for both substances, in an aqueous environment with pH 7, they will be present almost exclusively as 2-mercaptoethanol. Further, no effects on aqueous toxicity from the sodium cation is to be expected.
The toxicity to microorganisms was examined in a study according to DIN 38412 (part 8) (BASF, 1988). In this study cultures of Pseudomonas putida were exposed to the substance at test substance concentrations of 0 (control), 15.63, 31.25, 62.5, 125, 250 and 500 mg/L for 17 hours. After the exposure period the biomass measured (as optical density at 436 nm) and possible inhibition on growth investigated. From this study a 17-h EC50 value of 125 mg/L and 17-h EC10 value of 60 mg/L were derived. These data are used as key values for assessment. After correction for molecular weight difference (for read-across) the 17-h EC50 and 17-h EC10 values are 160.2 mg/L and 76.9 mg/L, respectively.
In addition a publication is available that describes the toxicity of, among others, 2-mercaptoethanol to microorganisms under anaerobic (methanogenic) conditions (Skylar, 1999). The toxicity of the target compounds was studied with regard to their influence on aceticlastic methanogenic activity of anaerobic sludge at test concentrations of 0 (control), 500, 1000, 2000, 5000, 7500 and 10000 mg/L. A 24 -h IC50 of 2800 mg/L was determined. After correction for molecular weight difference (for read-across) the 24 -h IC50 is 3588 mg/L.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
