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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 205-187-4 | CAS number: 135-37-5
Toxicity to aquatic algae and cyanobacteria
Administrative data
Link to relevant study record(s)
Description of key information
One reliable guideline study with the actual substance was performed by Dow according to the guideline. This study is considered the key study.The ErC50 (4d) was concluded 399 mg/L and the NOEC(4d) was 12 mg/L based on nominal concentration. These values were confirmed by other studies with a structurally similar substance Na3NTA, see read across justification.
In addition, BASF (1999) provided results of 72 hr EC50 of >91.5 mg/L (biomass and growth) and 72 hr ErC10 of 74.8 mg/L Na3NTA for Scenedesmus subspicatus. The study was performed according to OECD 201 and GLP and can be considered supportive, see the read across justification.
Key value for chemical safety assessment
- EC50 for freshwater algae:
- 399 mg/L
- EC10 or NOEC for freshwater algae:
- 12 mg/L
Additional information
Toxicity data for algae of substances with chelating properties should always be considered with care. Direct toxicity or indirect toxicity via (micro)nutrient deprivation might not always be clearly demonstrated in algal studies.
From the available information - incl structural analogue Na3NTA- it can be concluded that EDG is not acutely nor chronically toxic to algae (chronic endpoint > 10 mg/L). However, it was shown that both hardness (Weaver, 1967) as well as the nutrient composition of the test medium (Millington, 1988) can affect the outcome; soft water showing higher toxicity, ISO/BBM medium showing less toxicity compared to OECD or EPA medium composition.
Although the Millington (1988) study might not be that reliable wrt concluding the EC50 or EC10 value, it does allow comparison under the same circumstances wrt algal test media. In addition, the study by Bringmann & Kuhn (1977) - despite its flaws - confirms the conclusion above (WoE).
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.
