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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 231-449-2 | CAS number: 7558-80-7
Endpoint summary
Administrative data
Description of key information
Additional information
Typically the purity of sodium dihydrogenorthophosphate is > 90% (dry weight, after excluding water). All impurities present at >1% are other inorganic phosphates or other related inorganic substances, similar to the Registered substance, and which do not significantly affect its toxicological and ecotoxicological properties. There are no hazardous impurities present within the substance at levels >0.1%.
Sodium dihydrogenorthophosphate has a melting point of >450°C and is considered to be very soluble (>50.2 <52 % (w/w) at 20°C). The pH of this solution, observed in the water solubility study, was between pH3.6 to pH 4. The water solubility study conducted on sodium dihydrogenorthophosphate made the following observations:
The test material studied is essentially sodium dihydrogenorthophosphate following a degree of basification. For example, if an existing, acidic sample solution of sodium dihydrogenorthophosphate was adjusted towards a basic pH by the addition of sodium hydroxide, the resulting salt formed would be that of disodium hydrogenorthophosphate. As water solubility data for this analogous salt exists (>23.8 < 25.1 % (w/w) at 20°C, pH 9.2. O’Connor BJ, 2009, Harlan Laboratories Ltd, 2920/0004) and as it incorporates the environmentally relevant pH of interest, it can be concluded that the solubility of the sodium dihydrogenorthophosphate would decrease slightly as the pH increased over the pH range of 4 to 9. However, it must be noted that solubility would still remain high (in the range 23.8 to 25.1% w/w at 20°C, pH 9.2) and such a decrease would only be observed if significant buffering capacity was present which prevented the formation of an acidic solution as formed on dissolution of the test material.The temperature range of 10 to 30°C had no significant influence on the observed solubility of the test material.
Sodium dihydrogenorthophosphate is not considered to possess any of the following hazardous physico-chemical properties: autoflammability and/or self-ignition, flammability, explosiveness and oxidising properties.
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.
