2,2-bis[[(1-oxopentyl)oxy]methyl]propane-1,3-diyl divalerate

Short-term toxicity to fish

Description of key information

No toxic effects to freshwater fish up to the limit of water solubility.

Additional information

In accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5 a read across to four structurally related category members pentaerythritol tetraesters of n-decanoic, n-heptanoic, n-octanoic and n-valeric acids (CAS-No. 68424-31-7), decanoic acid, mixed esters with heptanoic acid, octanoic acid, pentaerythritol and valeric acid (CAS No. 71010-76-9), fatty acids, C5-9 tetraesters with pentaerythritol (CAS 67762-53-2) and fatty acids, C8-10 mixed esters with dipenaterythritol, isooctanoic acid, pentaerythritol and tripentaerythritol (CAS 189-200-42-8) in order to fulfil the data requirements according to Annex VII-IX. This read-across is justified in detail in the overall summary (IUCLID chapter 6.1) and within the category justification in IUCLID Section 13. In this case of read-across, the best suited (highest degree of structural similarity, nearest physico-chemical properties) read-across substances were used for the assessment. All read-across substances have the same alcohol component, i.e. pentaerythritol (CAS 189200-42-8 additionally contains dipenaterythritol and tripentaerythritol), and are tetra-esters with a fatty acid chain length within the range of C5 – C10 comparable to the target substance with chain length of C5.

In the first key study, the short term toxicity of CAS 68424-31-7 to freshwater fish was investigated in a semi-static limit test (Combert and Caunter, 1991) conducted according to a guideline similar to OECD 203 using Salmo gairdneri as a test organism. This study determined LC50 (96h) > 1000 mg/L (nominal). The test material did not dissolved completely in the dilution water. No mortality was observed within the tested concentration (1000 mg/l nominal) during 96h exposure under test conditions. Based on these results it can be concluded that no toxicological effects on freshwater fish are expected up to limit of water solubility.

In a further study with decanoic acid, mixed esters with heptanoic acid, octanoic acid, pentaerythritol and valeric acid (CAS No. 71010-76-9) the short-term toxicity to freshwater fish was investigated according to OECD 203 under static conditions using Brachydanio rerio as test organism (Lili, 2009). Nominal test concentrations of 100 and 150 mg/L were applied. Test substance monitoring using TOC analysis measured test concentrations of 0.696 and 0.704 mg/L, respectively. Undissolved test material was not removed from the test system; however, this is considered negligible, because no mortality was observed in any treatment and the control throughout the test period of 96 h. Hence, the 96 h-LC50 is determined to be > 0.704 mg/L (measured value, arithmetic mean) and thus above the limit of water solubility (< 0.02 mg/L).

Furthermore, short-term toxicity of fatty acids, C5-9 tetraesters with pentaerythritol (CAS 67762-35-2) to freshwater fish was investigated in a study according to OECD 203 under static conditions using Cyprinus carpio as test organism (Migchielsen, 2012). A nominal test concentration of 100 mg/L (prepared as WAF) was applied. Test substance monitoring measured a concentration of 4.8 mg/L. The final test solution was slightly hazy with a floating layer; however, this is considered negligible, because no mortality was observed in the treatment throughout the test period of 96 h. Hence, the 96 h-LL50 is determined to be > 100 mg/L (nominal) and > 4.8 mg/L (measured) and thus above the limit of water solubility (< 0.006 mg/L, purified water).

In addition, an acute study with fatty acids, C8-10 mixed esters with dipenaterythritol, isooctanoic acid, pentaerythritol and tripentaerythritol (CAS 189200-42-8) was conducted according to EPA OTS 797.1400 (fish acute toxicity test, 1987) under semi-static conditions using Pimephales promelas as test organism (Targia, 1994). The monitoring of the test substance concentrations confirmed that the substance is poorly soluble in water. As the test substance concentration was not found to be stable during the test, the effect values are related to the nominal concentration. Hence, the 96 h-LC50 is determined to be > 5 mg/L (nominal) and thus above the limit of water solubility (< 0.15 mg/L).

Based on these results from structurally related read-across substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5) which are characterized by a similar ecotoxicological profile, it can be concluded that 2,2-bis[[(1-oxopentyl)oxy]methyl]propane-1,3-diyl divalerate (CAS-No.15834-04-5) will not exhibit short-term toxic effects to freshwater fish up to the limit of water solubility.

As it can be seen in the data matrix of the category justification in section 13 and the overall summary, all reliable data in the category support the hazard assessment of each category member by showing a consistent pattern of results; no toxicological effects up to the limit of water solubility.