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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 215-170-3 | CAS number: 1309-42-8
Endpoint summary
Administrative data
Description of key information
Magnesium has no short-term toxicity to fish. The key and supporting studies found that magnesium hydroxide has a very low toxicity to all fish tested (LC50 > 100 mg/L).
Also, for Daphnia no short-term toxicity was shown, the EC50 values were above 100 mg/L.
According to the study on algae, both the EC50 for growth rate reduction (ErC50: 72h) and the EC50 for yield inhibition (EyC50: 72h) exceeded an analytically confirmed concentration of 100 mg/L, the NOEC is 100 mg/L.
Magnesium hydroxide was not toxic to waste water (activated sludge) bacteria at a loading rate of 100 mg/l. The 3-hour EC50 of magnesium hydroxide exceeded a loading rate of 100 mg/l.
Long-term toxicity of fish or daphnia is unlikely to occur based on the physico-chemical properties of magnesium hydroxide, the breakdown pathway of the substance and the fact that magnesium ions are ubiquitous in the natural environment.
Magnesium hydroxide is of low acute toxicity to aquatic organisms and does not meet the criteria to be classified as dangerous under the CLP Regulation (EC) No 1272/2008 nor does it meet the criteria to be classified as persistent, bioaccumulative or toxic under the REACH Regulation.
Additional information
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.
