Fatty acids, C6-12, mixed tetraesters with heptanoic acid, pentaerythritol, 3,5,5-trimethylhexanoic acid and valeric acid

Endpoint summary

Additional information

There are no data available investigating the aquatic toxicity ofPentaerythritol tetraesters of n-C5, n-C7, n-C8, i-C9 and n-C10 fatty acids (EC 451-190-0). In order to fulfil the standard information requirements set out in Annex VII, 9.2.1.1, in accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006, read-across from a structurally related source substance 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 (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 a suitable source substance was selected for hazard assessment.

Based on the specification the target substance Pentaerythritol tetraesters of n-C5, n-C7, n-C8, i-C9 and n-C10 fatty acids (EC 451-190-0) is characterized by the alcohol component pentaerythritol tetraesterified with mainly fatty acids of C5, C7, C8, C9iso and C10. The source substance, selected to cover aquatic toxicity, is specified as followed:

Reaction product of pentaerythritol and trimethylolpropane with n-pentanoic acid, 2-methylbutyric acid, n-heptanoic acid, 3,5,5-trimethylhexanoic acid, n-octanoic acid and n-decanoic acid (hereafter referred to as PE/TMP tetra/tri C5, i-C5, C7, C8, i-C9, C10 ester) consisting of pentaerythritol tetraesters and trimethylolpropane triesters with the same fatty acids as specified for the target substance.

A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

Short-term aquatic toxicity data are available for all trophic levels from a suitable source substance. Long-term data are available for algae. Due to the very low water solubility a long-term study with aquatic invertebrates was considered necessary to evaluate the chronic toxicity. However, this study is still on-going. The Chemical Safety Assessment according to Annex I of Regulation (EC) No 1907/2006 will be re-evaluated as soon as the additional study is available.

Based on the available experimental data, the toxicity to aquatic organisms is low. Additionally, the exposure concentrations for aquatic organisms are expected to be very low, due to the efficient removal in sewage treatment plants since the substance is readily biodegradable. Moreover, the substance is characterised by low water solubility and has a potential for adsorption, which further contributes to the removal from waste water.

The short-term toxicity to fish was investigated in a standard guideline study (from the source substance PE/TMP tetra/tri C5, i-C5, C7, C8, i-C9, C10 ester). No mortality was observed after 96 h resulting in a LL50 > 100 mg/L (i.e. above the water solubility limit). In experimental studies with the same source substance according to OECD guidelines no immobilization of Daphnia magna and no inhibition of growth of aquatic algae were observed up to the limit of water solubility. Thus, EL50 values > 100 mg/L were recorded also for the short-term toxicity to aquatic invertebrates and to aquatic algae.

The necessity of long-term toxicity testing to fish will be evaluated after the chronic study with aquatic invertebrates is finalised. However, a long-term study with 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. Available information taken from an OECD 209 study (from the source substance PE/TMP tetra/tri C5, i-C5, C7, C8, i-C9, C10 ester) performed with activated sludge from sewage treatment plants did not indicate a risk since the respiration rate of microorganisms was not inhibited (NOEC (3 h) ≥ 1000 mg/L).

Based on the result from a structurally related source substance it can be concluded thatPentaerythritol tetraesters of n-C5, n-C7, n-C8, i-C9 and n-C10 fatty acids (EC 451-190-0)exhibits no toxic effects on freshwater organisms up to the limit of the water solubility. Data gaps were covered by read-across, in accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5 Grouping of substances and read-across. Read-across substances were chosen based on the similarity of the molecular structure and of physico-chemical properties. A detailed justification for the grouping of chemicals and read-across is provided in the technical dossier (see IUCLID Section 13).