2-ethyl-2-(hydroxymethyl)-1,3-propanediyl dioleate

Endpoint summary

Additional information

There are no data available investigating the aquatic toxicity of 2-ethyl-2-(hydroxymethyl)-1,3-propanediyl dioleate (CAS 25111-05-1). 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 available information on the source substances is used to predict the same endpoints for 2-ethyl-2-(hydroxymethyl)-1,3-propanediyl dioleate (CAS 25111-05-1). The target substance is characterized by C18 unsaturated fatty acid esterified trimethylolpropane (TMP) (mainly di- and triester). The selected source substances are structurally very similar to the target substance and are thus adequate for the assessment of aquatic toxicity. Fatty acids, C16-18 even numbered and C18-unsatd. triesters with propylidynetrimethanol (former CAS 57675-44-2) is characterized by C18, C18 unsatd fatty acids triesterified with TMP. Fatty acids, C8-10 (even), C14-18 (even) and C16-18 (even)-unsatd., triesters with trimethylolpropane (former CAS 85186-89-6) mainly consists of C18:1 FA triesterified with TMP. The third source substance Fatty acids, C16-18 (even numbered) and C18-unsatd., branched and linear, di- and triesters with trimethylolpropane (former CAS 85005-23-8) is characterized as a triester of TMP and C16-C18 and C18 unsatd. branched and linear fatty acids. The fourth source substance Fatty acids, C16-18 and C18 unsatd., triesters with trimethylolpropane (CAS 68002-78-8) is characterized by C18 unsatd fatty acids triesterified with TMP.
A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

All available experimental data on the source substances performed according to internationally accepted guidelines indicate no evidence of acute and chronic toxicity to aquatic organisms. Data for all three trophic levels are available. 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 1.26 µg/L - 13.54 µg/L at 20 °C, pH=6.3 (OECD 105), mean: 7.40 µg/L.

The short-term toxicity to fish was determined in standard OECD guideline studies with freshwater and marine fish (from the source substances Fatty acids, C16-18 even numbered and C18-unsatd. triesters with propylidynetrimethanol (former CAS 57675-44-2), Fatty acids, C8-10 (even), C14-18 (even) and C16-18 (even)-unsatd., triesters with trimethylolpropane (former CAS 85186-89-6) and Fatty acids, C16-18 (even numbered) and C18-unsatd., branched and linear, di- and triesters with trimethylolpropane (former CAS 85005-23-8)). No mortality was observed after 96 h up to the limit of water solubility. 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 (from the source substances Fatty acids, C16-18 even numbered and C18-unsatd. triesters with propylidynetrimethanol (former CAS 57675-44-2) and Fatty acids, C8-10 (even), C14-18 (even) and C16-18 (even)-unsatd., triesters with trimethylolpropane (former CAS 85186-89-6).

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, C16-18 and C18 unsatd., triesters with trimethylolpropane (CAS 68002-78-8) resulted in a NOELR (21 d) ≥ 0.11 g/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. The experimental studies with the source substances Fatty acids, C16-18 even numbered and C18-unsatd. triesters with propylidynetrimethanol (former CAS 57675-44-2, Fatty acids, C8-10 (even), C14-18 (even) and C16-18 (even)-unsatd., triesters with trimethylolpropane (former CAS 85186-89-6) and Fatty acids, C16-18 (even numbered) and C18-unsatd., branched and linear, di- and triesters with trimethylolpropane (former CAS 85005-23-8) 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 2-ethyl-2-(hydroxymethyl)-1,3-propanediyl dioleate 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 suitable source substances support the read-across by showing a consistent pattern of results.