Fatty acids, C18 unsaturated, ethyl & methyl esters

Endpoint summary

Additional information

Data on the aquatic toxicity of Fatty acids, C18 unsaturated, ethyl & methyl esters (EC 941-981-3) are only available for fish and aquatic invertebrates. 
In accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006, read-across to the structurally related substances Fatty acids, C16-18 and C18-unsatd., iso-Bu esters (CAS 84988-79-4) and Fatty acids, safflower-oil, ethyl esters (CAS 91051-53-5) was conducted to fulfil the standard information requirements. 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). According to Annex XI, Item 1.5, of Regulation (EC) No 1907/2006 substances can be considered to be similar if their physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity.

Fatty acids, C18 unsaturated, ethyl & methyl esters (EC 941-981-3) is an UVCB substance consisting of ethanol and methanol esterified with poly- and monounsaturated C18 fatty acids. The source substance Fatty acids, safflower-oil, ethyl esters (CAS 91051-53-5) consists of ethanol esterified with a linear, poly-unsaturated fatty acid chain with two double bonds. The source substance Fatty acids, C16-18 and C18-unsatd., iso-Bu esters (CAS 84988-79-4) is an UVCB substance comprising linear saturated and unsatured fatty acid chains (C14 – C18) esterified with a linear C4 alcohole. The read across substances cover the chain length as well as the characteristics of saturated and unsatured fatty acid chains of the source substance. Target and source substances are characterised by a low water solubility, low vapour pressure and comparable log Koc values. Thus, the substances are expected to have a similar environmental fate and ecotoxicity profile.
In accordance with Regulation (EC) No 1907/2006, Annex XI, 1.5, grouping and read-across the target substance Fatty acids, C18 unsaturated, ethyl & methyl esters (EC 941-981-3) is considered not harmful to aquatic organisms based on the results of the available read across studies conducted with fish, aquatic invertebrates and algae and long-term results on toxicity to aquatic invertebrates up to the limit of water solubility.

The existing data on the target substance substance Fatty acids, C18 unsaturated, ethyl & methyl esters (EC 941-981-3) indicate that the substance is not acutely toxic to fish and aquatic invertebrates. Comparable results were obtained in a short-term toxicity study on Cyprinus carpio conducted with Fatty acids, safflower-oil, ethyl esters (CAS 91051-53-5). The substance is not acutely toxic to fish. The acute toxicity to algae was investigated in a study on the source substance Fatty acids, C16-18 and C18-unsatd., iso-Bu esters (CAS 84988-79-4). No effect on the algal biomass was observed in a test assay using the water accommodated fraction (WAF) of the substance in the test solution.

Data on chronic toxicity to Daphnia magna are available for Fatty acids, C16-18 and C18-unsatd., iso-Bu esters (CAS 84988-79-4). No mortality of detrimental effect on the reproduction was determined for the substance (NOELR (21 d) ≥ 100 mg/L).

Data on the toxicity to microorganisms are available for Fatty acids, safflower-oil, ethyl esters (CAS 91051-53-5). Effects of the source substance on the respiration rate of activated sludge were not determined.

The available acute toxicity data of the read-across substances demonstrate that toxic effects of the target substance Fatty acids, C18 unsaturated, ethyl & methyl esters (EC 941-981-3) up to the limit of water solubility are not likely. Consequently, additional acute and chronic testing is omitted. Based on the results from structurally related read-across substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5) it can be concluded that Fatty acids, C18 unsaturated, ethyl & methyl esters (EC 941-981-3) has no toxic effect on freshwater organisms up to the limit of the water solubility (WS ≥0.021 mg/L)