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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 824-774-1 | CAS number: 148124-40-7
Endpoint summary
Administrative data
Description of key information
EDTA is not readily biodegradable according to OECD criteria. In standard OECD 301D tests, EDTA complexes with a stability constant lower than 10E13 like EDTA-Na4, EDTA-CaNa2, EDTA-MnK2 etc. less than 60% biodegradation was observed after 28 days indicating that these substances should be not classified as readily biodegradable but in the same tests > 60% biodegradation was observed after 60 days in the prolonged (enhanced) tests indicating that these compexes, having stability constants < 10E13, are not persistent.
The EDTA-Fe(OH)K2 complex has a stability constant >10E12 and is therefore expected to be persistent according to OECD criteria, when tested in standard ready biodegradability tests. At lower environmentally more representative concentrations however significant biodegradation may occur. The level of this stability constant threshold dependents on the concentration balance between the starting complex and free metal ions (alkali and alkaline earth metals) in the matrix. The lower the starting concentration of the EDTA-metal complex the higher this stability constant threshold for biodegradation. EDTA-Iron complexes have a stability constant close to 10E23 and are expected to be persistent in standard ready biodegradability tests also at much lower test concentrations. The EDTA-Iron complexes are however senstive to photodegradation and at pH>7, iron tends to precipitate as Iron hydroxides liberating EDTA for degradation. The higher the pH the higher the decomplexation rate.
Additional information
EDTA is not readily biodegradable according to OECD criteria. It was shown that with natural river water as inoculum, in standard OECD 301D tests, EDTA complexes with a stability constant lower than 10E13 like EDTA-Na4, EDTA-CaNa2, EDTA-MnK2 etc. less than 60% biodegradation was observed after 28 days indicating that these substances should be not classified as readily biodegradable but in the same tests > 60% biodegradation was observed after 60 days in the prolonged (enhanced) tests indicating that these compexes, having stability constants < 10E13, are not persistent.
This stability constant threshold of 10E13 will be dependent on the concentration balance between the starting complex and free metal ions (alkali and alkaline earth metals). The lower the starting concentration of the EDTA-metal complex the higher this stability constant threshold for biodegradation.
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.
