Fatty acids, C18-unsatd., dimers, 2-ethylhexyl esters

Endpoint summary

Additional information

Justification for grouping of substances and read-across

There are no data available the toxicity to reproduction of Fatty acids, C18-unsatd., dimers, 2-ethylhexyl esters (CAS 68334-05-4). In order to fulfil the standard information requirements set out in Annex X, 8.7, 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 human toxicity, information shall be generated whenever possible by means other than vertebrate animal tests, which includes the use of information from structurally related substances and/or common chemical precursors or similar hydrolysis/breakdown products (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 and/or common chemical precursors or similar hydrolysis/breakdown products.

The read-across is either based structural similarity or on the metabolism of Fatty acids, C18-unsatd., dimers, 2-ethylhexyl esters (CAS 68334-05-4), in particular on the fact that the substance undergoes enzymatic ester hydrolysis resulting in the formation of Fatty acids, C18-unsatd., dimers and 2-ethylhexanol. A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

Endpoint specific data matrix:

ID	CAS	Short term toxicity to fish	Long term toxicity to fish	Short term toxicity to aquatic invertebrates	Long term toxicity to aquatic invertebrates	Toxicity to aquatic algae	Toxicity to microorganisms
Target Substance	68334-05-4	Experimental result:LL50 > 100 mg/L	RA: 68783-41-5	Experimental result:EL50 > 100 mg/L	Waiving	Experimental result:EL50 > 100 mg/L	Experimental result:NOEC ≥100 mg/L
Source 1	68783-41-5	RA: 61788-89-4	Experimental result: NOEC ≥ 0.85 mg/L	RA: 61788-89-4 RA: 68937-90-6	Waiving	RA: 61788-89-4 RA: 68937-90-6	RA: 61788-89-4

Acute tests evaluating the toxicity of of Fatty acids, C18-unsatd., dimers, 2-ethylhexylesters (CAS No. 68334-05-4) to aquatic organisms from three different trophic levels are available. For all three trophic levels (fish, aquatic invertebrates and algae) no toxicity within the range of water solubility was observed.

Long-term tests evaluating the toxicity of Fatty acids, C18-unsatd., dimers, 2-ethylhexylesters to aquatic organisms are only available for algae. The results of this test show no chronic effects within the range of water solubility. Furthermore, the results of a study assessing the chronic toxicity to fish of a structurally related substance show no effects up to the limit of the water solubility.

There is no long-term test on aquatic invertebrates available for Fatty acids, C18-unsatd., dimers, 2-ethylhexylesters (CAS No. 68334-05-4). The chemical safety assessment according to Annex I of Regulation (EC) No 1907/2006 does not indicate the need to investigate further the long-term toxicity to aquatic invertebrates. Thus, in accordance to Annex IX, column 2 no further long-term toxicity test to aquatic invertebrates is proposed. Available short-term studies for fish, daphnia and algae, indicate no potential for aquatic toxicity (no effects up to the limit of the water solubility). Moreover, the long-term NOELR from the algal growth study and the NOEC of the fish study performed with a structurally related substance are clearly above the limit of water solubility (< 1 mg/L).  

One GLP study conducted according to OECD guideline 209 over a period of 3 hours with activated sludge of a predominantly domestic sewage is available for Fatty acids, C18-unsatd., dimers, 2-ethylhexyl esters. No effects were observed under conditions tested up to limit of the water solubility. Thus, the test substance has only a low toxicity for activated sludge microorganisms and no inhibition of the degradation activity of activated sludge in sewage treatment plants is anticipated.

General conclusion

No effects on aquatic organisms were observed in the available studies for Fatty acids, C18-unsatd., dimers, 2-ethylhexylesters in any of the three trophic levels (fish, daphnia, algae) up to the limit of water solubility, neither in the short-term toxicity tests nor in long-term tests with algae and fish. Furthermore, toxic effects on microorganisms are not expected.