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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 240-934-8 | CAS number: 16893-85-9
Ecotoxicological Summary
Administrative data
Hazard for aquatic organisms
Freshwater
- Hazard assessment conclusion:
- PNEC aqua (freshwater)
- PNEC value:
- 0.9 mg/L
- Assessment factor:
- 10
- Extrapolation method:
- assessment factor
Marine water
- Hazard assessment conclusion:
- PNEC aqua (marine water)
- PNEC value:
- 0.9 mg/L
- Assessment factor:
- 10
- Extrapolation method:
- assessment factor
STP
- Hazard assessment conclusion:
- PNEC STP
- PNEC value:
- 51 mg/L
- Assessment factor:
- 10
- Extrapolation method:
- assessment factor
Hazard for air
Hazard for terrestrial organisms
Soil
- Hazard assessment conclusion:
- PNEC soil
- PNEC value:
- 11 mg/kg soil dw
- Assessment factor:
- 10
Hazard for predators
Additional information
Short term toxicity tests have been performed on disodium hexafluorosilicate. Toxicity to fish, algae and microorganism has been determined. However, there are no available data on long term toxicity to the aquatic environment, which are preferred to derive PNECs. Due to the presence of hydrolysable groups on its chemical structure, fluorosilicate anions are not expected to remain in solution long under environmental conditions. Instead, fluoride anions will be formed. Thus, the performance of such tests is unjustified, since there are reliable studies on sodium fluoride or hydrogen fluoride. Read-across to sodium fluoride is appropriate. Thus, PNECs will be derived based on long term studies on NaF.
Conclusion on classification
Aquatic toxicity values experimentally obtained for disodium hexafluorosilicate are the following: 96h EC50 (fish)= 37.5 mg/l 48h EC50 (daphnia)= 35.4 mg/l 72h ErC50 (alga)= 18 mg/l. The three of them are between 10 and 100 mg/l.
The substance readily dissociates in water and undergoes further hydrolysis is hydrolisable at environmental conditions, providing fluoride. Thus, the substance is unstable in water and therefore rapidly degradable. Moreover, as its bioaccumulation potential cannot be assessed, it is then justified to use biodegradation and bioaccumulation results on fluorides for assessment.
As indicated in endpoint 5.3.1, BCF for fluorides is lower than the threshold of 2000, meaning that the substance is considered not bioaccumulative.
Considering all data together, disodium hexafluorosilicate shall not be classified for aquatic toxicity.
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.
