Registration Dossier
Registration Dossier
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EC number: 213-427-4 | CAS number: 947-42-2
Ecotoxicological Summary
Administrative data
Hazard for aquatic organisms
Hazard for air
Hazard for terrestrial organisms
Hazard for predators
Additional information
Diphenylsilanediol (CAS 947-42-2) is part of a group of organosilicon substances, the ecotoxicity of which is determined by a non-polar narcosis mechanism of toxicity, and as such log Kow drives toxicity. Substances in this group include silanols and alkoxy- and chloro-silanes having secondary features that do not affect the toxicity of the substances. The side chains of the registered substance are aryl (phenyl). There is evidence that the phenyl groups’ toxicity is related to log Kow alone, as for other neutral organics (narcotics) and thus does not enhance toxicity. Additional information is given in the following supporting report: PFA, 2016y, Peter Fisk Associates, Analogue Report - Ecotoxicity of substances with ‘low-functionality’ side chains attached to silicon ,
PFA.300.003.004, attached in Section 13 of the IUCLID 5 dossier.
The registered substance is a silanediol containing two phenyl groups and is not susceptible to hydrolysis. It has a low predicted log Kow (2 at 20°C) and is moderately soluble in water (predicted water solubility of 510 mg/l), although the concentration dissolved in water is limited to about 25 - 100 mg/l by condensation reactions (see section 4.8 of IUCLID for more information). The substance is not readily biodegradable, based on read-across data.
Reliable measured data are available for the registration substance for short-term toxicity to fish, aquatic invertebrates and aquatic algae.
Conclusion on classification
The substance has reliable short-term E(L)C50values of 39 mg/l in fish, 24 mg/l in invertebrates and 9 mg/l in algae. A reliable NOEC value of 1.1 mg/l with algae is also available. No chronic studies are available for fish or invertebrates.
The substance does not hydrolyse in water and is not readily biodegradable.
These data are consistent with the following classification under Regulation (EC) No 1272/2008 (as amended) (CLP):
Acute toxicity: Not classified.
Chronic toxicity: Category 2, H411: Hazardous to the aquatic environment
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.
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