Fatty acids C18-C22 (even numbered), tetraesters with pentaerythritol

Endpoint summary

Additional information

There are no ecotoxicological data available for fatty acids C18-C22 (even numbered), tetraesters with pentaerythritol. Therefore, read-across to the structurally related substances fatty acids, C16-18 and C18-unsatd., esters with pentaerythritol (CAS 85711-45-1), 2,2-bis[[(1-oxoisooctadecyl)oxy]methyl]-1,3-propanediyl bis(isooctadecanoate) (CAS 62125-22-8), decanoic acid, mixed esters with heptanoic acid, octanoic acid, pentaerythritol and valeric acid (CAS 71010-76-9), pentaerythritol tetraoleate (CAS 19321-40-5) and fatty acids, C16-18 and C18-unsatd., tetraesters with pentaerythritol (CAS 68604-44-4) was conducted in order to fulfill the standard information requirements in compliance with Annex XI, 1.5, of Regulation (EC) No 1907/2006. Based on the high degree of similarity between the structural and physico-chemical properties of the target and source substances, these are considered as suitable representatives for the assessment of the short-term toxicity to fish, short and long-term toxicity to aquatic invertebrates, algae and toxicity to microorganisms of the target substance. A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

All experimental studies available for the source substances were performed according to internationally accepted guidelines. The lowest endpoint for short-term toxicity to fish was determined to be LC50 > 100 mg/L (nominal). For aquatic invertebrates the EL50 was determined to be > 100 mg/L (nominal) and the NOELR ≥ 1 mg/L (nominal). For algae the EL50 was determined to > 100 mg/L and the NOELR ≥ 100 mg/L (nominal). An EC50 and EC10 of > 10000 mg/L were determined for microorganisms.

In addition, aquatic toxicity of the substance is unlikely to occur due to the low bioavailability of the substance in water. Based on the high potential for adsorption, the substance can be effectively removed in conventional sewage treatment plants (STPs) by sorption to biomass. The low water solubility (< 0.518 mg/L at 20 °C, OECD 105) and high estimated log Kow (> 10, QSAR, VEGA 1.1.3) indicate that the substance is highly lipophilic. If released into the aquatic environment, the substance undergoes extensive sorption on organic matter. Thus, the bioavailability in the water column is reduced rapidly. The relevant route of uptake of the substance in aquatic organisms is expected to be predominantly by ingestion of particle bound substance. However, as the substance has a high molecular weight of 1370.31 – 1426.42 g/mol, it is unlikely that it is readily absorbed, due to the steric hindrance to cross biological membranes.

Based on the available results from structurally related source substances, a low bioavailability of the substance and a steric hindrance of crossing biological membranes, it can be concluded that fatty acids C18-C22 (even numbered), tetraesters with pentaerythritol will not exhibit aquatic effects up to the limit of water solubility.