Titanium tetrakis(2-ethylhexanolate)

Endpoint summary

Additional information

Titanium tetrakis(2-ethylhexanolate) is hydrolytically unstable. The progress of the hydrolysis was followed by monitoring 2-ethylhexanol, the main degradation product of the substance (Brekelmans M.J.C. 2013). Recoveries of 2-ethylhexanol were used to evaluate the hydrolytic stability of the substance. The other non-hazardous degradation product (hydrated titanium oxide) is insoluble lacking bioavailability in aquatic environment, and therefore not further considered in CSA.

Because of the rapid hydrolysis, the intrinsic properties of aquatic toxicity are related to the main degradation product (2-ethylhexanol). Key studies for the analogue category member (titanium tetra(octanolate), branched and linear, CAS 68526 -83 -0) justify that these organometallic titanates hydrolyse during toxicity testing and the aquatic toxicity is similar to the alcohol released in water. Due to the rapid hydrolysis in aqueous test media, the degradation products (isooctyl alcohols isomers and hydrated titanium dioxides) toxicity to the freshwater invertebrates and algae were investigated based on the measured isooctyl alcohols isomers concentrations and the equivalent test item concentrations.

This read-across substance is an analogue substance grouped together with the target substance into the category of highly water reactive titanates. It contains commercial solvent (alcohols C7 -9-iso, C8-rich, CAS no 68526 -83 -0). This solvent contains 93 % of isooctanol being also an analogue substance with 2 -ethylhexanol; an isomer of octyl alcohol. Category and read-across justifications are presented in the annexes of the CSR.

Based on the high reactivity of this substance in water, the short-term and long-term aquatic toxicity testing was considered scientifically unjustified and the read-across data from the main degradation product (2-ethylhexanol) and the analogue category member was used as a key value in CSA.

Short-term toxicity to fish:

•96-h LC50 (mortality) to Leuciscus idus melanotus (golden orfe), 17.1 mg/L based on measured concentrations (read-across from 2-ethylhexanol; Scholz 1991)

Short term toxicity to invertebrates:

•48-hour LC50 (immobilisation) to Daphnia magna, 40 mg/L based on measured concentrations (read-across from 2-ethylhexanol (Scholz 1991) and the analogue category member titanium tetra(octanolate), branched and linear; OECD 202 (Tobor-Kapłon 2013)

Toxicity to algae:

•72h-NOEC (growth rate) to Scenedesmus subspicatus, 2 mg/l based on measured concentrations (read-across from 2-ethylhexanol (Scholz 1991) and the analogue category member titanium tetra(octanolate), branched and linear; OECD 201 (Tobor-Kapłon 2013)

•72h-EC50 (growth rate) to Scenedesmus subspicatus, 16.6 mg/l based on measured concentrations (read-across from 2-ethylhexanol (Scholz 1991) and the analogue category member titanium tetra(octanolate), branched and linear; OECD 201 (Tobor-Kapłon 2013)

Toxicity to microorganisms:

•16 h-Toxicity Threshold (cell multiplication) to Pseudomonas putida, 110 mg/l based on nominal concentrations (DIN 38412 part 8; read-across from 2-ethylhexanol; Bringmann &Kuhn 1980 and Staples 2001)