Fatty acids, coco, 2-ethylhexyl esters

Short-term toxicity to fish

Description of key information

No toxic effects up to the limit of water solubility for Lepomis macrochirus (EPA 660/3-75-009 (1975))

Additional information

Only an incomplete study report is available on the fish toxicity of Fatty acids, coco, 2-ethylhexyl esters (CAS No. 92044-87-6)S. The assessment of fish toxicity was therefore based on studies conducted with the structurally most similar category members, for which data is available, dodecanoic acid hexyl ester (CAS No. 34316-64-8) and isopropyl myristate (CAS No. 110-27-0), as part of a read across approach, which is in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5. Grouping of substance and read across approach. Further justification is given within the endpoint summary 6.1 and within the category justification section 13. In this case of read-across, the best suited (highest degree of structural similarity, nearest physico-chemical properties) read-across substance was entered into IUCLID. Nevertheless, as can be seen in the data matrix of the category justification in Section 13, all reliable data in the category support the hazard assessment for this endpoint, by showing a consistent pattern of results.

The key study with isopropyl myristate (CAS No. 110-27-0) was performed according to the guideline EPA 660/3-75-009 (1975) (Sousa, 1979). The test organism Lepomis macrochirus was exposed to the test substance in a static system for 96 hours, at the nominal test concentrations of 78, 130, 220, 360, 600 and 1000 mg/L. No mortality occurred at any of the test concentrations during the test period, and the LC50 was reported to be > 1000 mg/L.

The key study conducted with dodecanoic acid hexyl ester (CAS No. 34316-64-8) was performed according to the guideline ISO 7346-1 (similar to OECD 203), in a semi-static system, using Brachydanio rerio as test organism (Guhl, 2005). The fish were exposed to nominal test concentrations of 100, 300, 700, 1000, 3000 and 10000 mg/L during 96 hours. Significant mortality occurred at the two highest test concentrations, and an LC50 of 2200 mg/L was derived. However, the test concentrations in this study were far above the saturation limit of the test substance, and undissolved test material was not removed from the test solutions. The sudden increase in mortality from 0% at concentrations 100 – 1000 mg/L to 70% at 3000 mg/L is better explained by a physical effect, caused by the amount of undissolved material in the test solution, rather than a systemic toxic effect. It is therefore probable that no toxic effects occurred up to the limit of water solubility of the test substance.

The study with Fatty acids, coco, 2-ethylhexyl esters (CAS No. 92044-87-6), used as supporting study, was performed as a limit test according to OECD guideline 203 (Sewell, 1992). The test organism Oncorhynchus mykiss was exposed to the test substance in a semi-static system for 96 hours, at the nominal test concentration of 2 mg/L, which was the highest concentration that could be achieved with the amount of solvent permitted by the guideline. The LC50 was determined to be above 2 mg/L and thus above the water solubility of the test substance (<0.05 mg/L).

Thus, based on theabove mentioned results, and due to the structural and profile similarities of the two substances, as are explained with in the overall endpoint summary 6.1 it can be concluded that no toxicological short-term effects on fish are expected up tothe limit ofwater solubility for Fatty acids, coco, 2-ethylhexyl esters (CAS No. 92044-87-6).