potassium titanium oxide (K2Ti6O13)

Long-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

fish short-term toxicity test on embryo and sac-fry stages

Type of information:

experimental study planned

Justification for type of information:

TESTING PROPOSAL ON VERTEBRATE ANIMALS

NON-CONFIDENTIAL NAME OF SUBSTANCE:
- Name of the substance on which testing is proposed to be carried out: potassium hexatitanate
- Name of the substance for which the testing proposal will be used [if different from tested substance]: none

- EC number: 432-240-0
- CAS number: 12056-51-8
- type: inorganic

CONSIDERATIONS THAT THE GENERAL ADAPTATION POSSIBILITIES OF ANNEX XI OF THE REACH REGULATION ARE NOT ADEQUATE TO GENERATE THE NECESSARY INFORMATION:
- Available GLP studies: No available GLP studies on the substance for the endpoint long-term toxicity to fish.
- Available non-GLP studies: No available non-GLP studies on the substance for the endpoint long-term toxicity to fish.
- Historical human data: Human data are not applicable since the endpoint for which the testing is proposed is the long-term toxicity to fish.
- (Q)SAR: in general, the long-term toxicity to fish can be predicted by the model "Fish, ChV" that is contained in the software ECOSAR (US EPA), as reported in the ECHA document "Practical Guide - How to use and report (Q)SARs 3.1. 2016." at Table c. Ecotoxicological endpoints. However, ECOSAR cannot be used for all chemical substances. The intended application domain is organic chemicals so, inorganic chemicals are outside the applicability domain. Potassium hexatitanate is an inorganic substance so it is outside of the applicability domain of the models and the available models are not suitable to predict the long term toxicity to fish for an inorganic substance.
Others software, with others models or other models for the prediction of the long-term toxicity testing on fish are not available, as reported in "Practical Guide - How to use and report (Q)SARs 3.1. 2016", p.32.

- In vitro methods: In accordance with ECHA's guidance on the information requirements and chemical safety assessment, charpter R7b; at present, there are no EU/OECD guidelines for in vitro tests of relevance to aquatic toxicity. There are ongoing efforts to develop and validate in vitro methods, which in future might be useful in a testing strategy for acute aquatic toxicity (e.g. ECVAM study on optimisation of cytotoxicity tests and CEFIC LRi study ECO 8 aiming to replacing the acute fish toxicity test using fish cell lines and fish embryos). The use of fish cells in environmental toxicology was reviewed at the ECVAM workshop (Castano et al., 2003, ECVAM workshop report 47) and ECETOC (2005).

- Weight of evidence: according to ECHA guideline "Practical guide 10: How to avoid unnecessary testing on animals. 2010", this approach may be applied if there is sufficient information from several independent sources leading to the conclusion that a substance has (or has not) a particular dangerous property, while the information from each single source alone is regarded insufficient to support this assertion.
As detailed above, no studies and no information related to long term toxicity to fish are available so, a weight of evidence approach cannot be performed.

- Grouping and read-across: since no studies related to long-term toxicity to fish are available from the similar substance (i.e. potassium octatitanate CAS: 59766-31-3, EC: 261-919-2), the read-across approach is not applicable.
- Substance-tailored exposure driven testing: not applicable - substance is used in wide-dispersive uses.
- Approaches in addition to above: not applicable.
- Other reasons: not applicable.

CONSIDERATIONS THAT THE SPECIFIC ADAPTATION POSSIBILITIES OF ANNEXES VI TO X (AND COLUMN 2 THEREOF) OF THE REACH REGULATION ARE NOT ADEQUATE TO GENERATE THE NECESSARY INFORMATION:

The need to conduct further testing (other than short toxicity tests) may be triggered by the results from a qualitative assessment, where a possible risk should be confirmed/rejected, e.g. when due to low water solubility of a substance, short term toxicity tests do not reveal any toxicity, long-term tests are performed - as reported in ECHA Guidance document Chapter R.7b: endpoint specific guidance. V. 3.0. 2016.

The substance of interest is poorly water soluble; the test available and reported in the technical dossier was performed according EU Guideline and it is GLP compliant. Under the test conditions (Temp. 20 °C and pH 6.2) the water solubility is below 1 mg/L.

Available short term toxicity data (i.e. short-term toxicity to fish, short-term toxicity to aquatic invertebrates and toxicity to aquatic algae and cyanobacteria), as reported in the technical dossier, were performed according to EU Method guidelines and it do not reveal any toxicity, so a long-term toxicity test to fish is proposed.

FURTHER INFORMATION ON TESTING PROPOSAL IN ADDITION TO INFORMATION PROVIDED IN THE MATERIALS AND METHODS SECTION:
- Details on study design / methodology proposed: According to ECHA Guidance R 7b, the specified test method (i.e. OECD 212) represents a suitable toxicity test for substances characterized by a log Kow less than 4.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 212 (Fish, Short-term Toxicity Test on Embryo and Sac-Fry Stages)

Deviations:

not specified

GLP compliance:

not specified

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

As suggested by the ECHA Guideline R7.b page 31, the reccommended species are Danio rerio, Pimephales promelas, Cyprinus carpio, Oryzias latipes and Oncorhynchus mykiss.

Description of key information

testing proposal