Fatty acids, C14-18, C14-18-alkyl esters

Short-term toxicity to fish

Description of key information

No effects up to the limit of water solubility (< 0.02 mg/L at 20 °C, pH 6.3).

Additional information

Since no studies investigating the short-term toxicity of Fatty acids, C14-18, C14-18-alkyl esters (CAS 85566-24-1) to fish are available, in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5 a read-across to the structurally related source substances Fatty acids, C16-18, C12-18-alkyl esters (CAS 95912-87-1), Tetradecanoic acid, tetradecyl ester (CAS 3234-85-3) and Fatty acids, C8-10, C12-18-alkyl esters (CAS 95912-86-0) was conducted. The source substances are representative to evaluate the short-term toxicity of the target substance to fish. The target substance is characterized as an ester of mainly C14 fatty acid/C14 alcohol, C16 fatty acid/C14 alcohol and C16 fatty acid/C16 alcohol. The three source substances are structurally very similar to the target substance. Fatty acids, C16-18, C12-18-alkyl esters (CAS 95912-87-1) is a UVCB substance consisting of C16-C18 fatty acids esterified with C12-C18 alcohol. Tetradecanoic acid, tetradecyl ester (CAS 3234-85-3) is a mono-constituent substance of a C14 fatty acid esterified with C14 alcohol. Fatty acids, C8-10, C12-18-alkyl esters (CAS 95912-86-0) is a UVCB substance consisting of mainly C8-C10 fatty acids esterified with C12-C14 alcohol. This read-across is justified in detail in the overall summary (IUCLID Section 6.1) and within the analogue 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 substance was used for the assessment.

The first study was performed according to OECD 203 (GLP) and investigated the short-term toxicity of tetradecyl myristate (CAS 3234-85-3) to freshwater fish (Teigeler, 2012).The zebra fish Danio rerio was exposed for 96 h to a limit Water Accommodated Fraction (WAF) concentration of nominal 100 mg/L.GC/EI-MS analysis resulted in a measured initial concentration of 0.189 µg/L which dropped below the detection limit of 0.1 µg/L at the end of exposure after 96 h. No mortality was observed resulting in a LL50 of > 0.189 µg/L (measured initial concentration) and > 100 mg/L (nominal), respectively.

The second study with the read-across substance Fatty acids, C8 - 10, C12 - 18-alkyl esters (CAS 95912-86-0) was performed according to OECD 203 (GLP; Salinas 2013). Danio rerio was exposed to a nominal concentration of 100 mg/L for 96 h (Water Accommodated Fraction). No mortality was observed after 96 h of incubation resulting in a LL50 (96 h) > 100 mg/L (nominal) and a NOELR (96 h) ≥ 100 mg/L (nominal).

The third study with the read-across substance fatty acids, C16-18, C12-18-alkyl esters (CAS 95912-87-1) was performed according to the EU Method C.1 (GLP) with the zebrafish Brachydanio rerio (Stelter, 1994). A static exposure regime was chosen. Three concentrations of nominal 1000, 3000 and 10000 mg/L were directly applied to the test vessels without a filtration step. Undissolved test material floated on top of the water surface but no effects were observed by the dissolved and even by the undissolved test substance present in the water. Thus, a LC50 (96 h) of > 10000 mg/L (nominal) was derived.

Based on the available results from structurally related source substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5) which are characterized by a similar ecotoxicological profile and comparable structure, it can be concluded that Fatty acids, C14-18, C14-18-alkyl esters will not exhibit short-term effects to fish up to the limit of water solubility.