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

Endpoint summary

Additional information

There are no data available investigating the aquatic toxicity of Fatty acids, C14-18, C14-18-alkyl esters (CAS 85566-24-1). In order to fulfil the standard information requirements, in accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006, read-across from structurally related substances was conducted.

In accordance with Article 13 (1) of Regulation (EC) No 1907/2006, "information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI are met.” In particular for aquatic toxicity, information shall be generated whenever possible by means other than vertebrate animal tests, which includes the use of information from structurally related substances (grouping or read-across).

Having regard to the general rules for grouping of substances and read-across approach laid down in Annex XI, Item 1.5, of Regulation (EC) No 1907/2006 whereby substances may be predicted as similar provided that their physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity.

The target substance and all source substances are considered to be similar on the basis of the structural similar properties and/or activities. The available endpoint information on the source substances is used to predict comparable results for the target substance Fatty acids, C14-18, C14-18-alkyl esters (CAS 85566-24-1).
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. A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

All available experimental studies available for the suitable source substance were performed according to internationally accepted guidelines. They cover all three trophic levels of an aquatic ecosystem. No toxicity was observed up to the limit of water solubility in all available experimental studies. The water solubility of the target substance was determined to be < 0.02 mg/L at 20 °C, pH 6.3.

The short-term toxicity to fish was determined in standard OECD guideline studies according to OECD 203 or EU Method C.1 (from the source substances CAS 95912-87-1, CAS 3234-85-3 and CAS 95912-86-0). No mortality was observed after 96 h resulting in a LL(C)50 > 100 mg/L or > 10000 mg/L (i.e. above the water solubility limit). The same was recorded for the short-term toxicity to aquatic invertebrates and to aquatic algae. No immobilization of Daphnia magna and no inhibition of growth of aquatic algae were observed in experimental studies according to OECD guidelines up to the limit of water solubility.

Due to the low water solubility, long-term testing with aquatic invertebrates was considered to be necessary to assess the aquatic toxicity. The available study performed with the suitable source substance Fatty acids, C8-10, C12-18-alkyl esters (CAS 95912-86-0) resulted in a NOELR (21 d) ≥ 10 mg/L indicating no effects on reproduction up to the limit of water solubility.

Long-term toxicity testing to fish was not considered to be necessary since there was no evidence from the available data that fish are more sensitive compared to aquatic invertebrates. No toxicity to fish was observed in the available acute tests. Thus, in order to avoid unnecessary vertebrate testing, no long-term testing with fish was proposed.

The degradation process in commercial sewage treatment plants is not suspected to be inhibited by the target substance. An experimental study with the source substance Fatty acids, C8-10, C12-18-alkyl esters (CAS 95912-86-0) did not indicate inhibition of respiration of activated sludge microorganisms.

Based on the result from structurally related read-across substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5) it can be concluded that the target substance Fatty acids, C14-18, C14-18-alkyl esters exhibits no toxic effects on freshwater organisms up to the limit of the water solubility. As it can be seen in the data matrix of the analogue justification in IUCLID Section 13, all reliable data from the source substances support the read-across by showing a consistent pattern of results.