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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 500-687-1 | CAS number: 162303-51-7
Short-term toxicity to aquatic invertebrates
Administrative data
Link to relevant study record(s)
Description of key information
Testing is not scientifically justified as this substance is hydrolytically unstable.Thus, toxicity of the decomposition products is used as a key value in CSA.
Key value for chemical safety assessment
Fresh water invertebrates
Fresh water invertebrates
- Effect concentration:
- 1 300 mg/L
Additional information
When this substance comes in contact with water or moisture, a complete hydrolysis will take place with no significant reaction products other than n-butanol and hydrated titanium dioxide (half-life < 2 hours, Brekelmans 2013). The organic decomposition product n-butanol is readily biodegradable and not persistent based on the log Kow value of 0.84. The CSA indicates that toxicity of this substance is similar to the main degradation product n-butanol.
Key studies (short-term toxicity to daphnia and algae) conducted for the analogue category member (titanium tetraisopropanolate CAS 546-68-9) justify that these organometallic titanates hydrolyse during toxicity testing and the aquatic toxicity is similar to the alcohol released in water. Category and read-across justifications are presented in the annexes of the CSR. Therefore, a short-term toxicity study on invertebrates is unjustified, and the key value for CSA is obtained from the studies conducted for n-butanol.
Two categories of highly water reactive titanates and moderately water reactive titanates are formed from the eight analogue organometallic titanates, because they all are hydrolytically unstable, and have mechanistic reasoning for read-across from the degradation products within the categories. The source substance for this target substance is n-butanol. The analogue organometallic titanate (bis(ethyl acetoacetato-O1', O3') bis(2 -methylpropan-1 -olato)titanium from the category of moderately water reactive titanates contains and releases 2-methylpropan-1-ol, which is an analogue to n-butanol released from this target substance. The structural analogy of 2-methylpropan-1-ol (CAS no 78 -83 -1) and n-butanol (CAS no 71-36-3) has also used to support the environmental hazard assessments of these alcohols in OECD SIDS initial assessment reports published by UNEP ( UNEP publications 2001 & 2004). Therefore, the toxicity of 2 -methylpropan-1 -ol is used in this weight of evidence approach to evaluate the toxicity of the target substance together with n-butanol data.
Based on the published study results, the 48-h EC50 (immobilisation) of n-butanol to Daphnia magna is 1983 mg/l (with 95 % CL of 1897 - 2072 mg/l) and the 24-h EC50-value 2237 mg/l (95 % CL 2117 -2363 mg/l), respectively ( Kuehn et al. 1989). According to Bringmann, G. & Kuehn, R. (1977), the 24-h EC50 (immobilisation) to D.magna is 1855 mg/l. Similar results have also been reported for 2 -methylpropan-1-ol (the 48 -h EC50, 1300 mg/l with CL 95 % 1200 -1400 mg/l; Elnabarawy et al. 1986).
In conclusion, as a conservative approach the lowest toxicity value of the degradation products is used as key value for CSA.
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.
