2,2-bis[[(1-oxoheptyl)oxy]methyl]propane-1,3-diyl bisheptanoate

Endpoint summary

Additional information

Data investigating the ready biodegradability of 2,2-bis[[(1-oxoheptyl)oxy]methyl]propane-1,3-diyl bisheptanoate (CAS 25811-35-2) are not available. In order to fulfil the standard information requirements set out in Annex VII, 8.5, in accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006, read-across from structurally related substances was conducted. 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 state that 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 target substance and source substances show structural similarities and are characterised by similar physico-chemical properties. The target and source substances are esters of a mono-, di-, tri-, tetra-functional alcohol with one or more carboxylic (fatty) acid(s) chain(s). The fatty acid moiety comprises carbon chain lengths from C5- C18. A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

All source substances are poorly soluble in water (WS < 1 mg/L), not volatile (<0.1 Pa) and have a high adsorption potential (log koc > 3).

2,2-bis[[(1-oxoheptyl)oxy]methyl]propane-1,3-diyl bisheptanoate (CAS 25811-35-2) is poorly soluble in water (< 0.05 mg/L) and has a low vapour pressure of (VP: < 0.001 Pa, SPARC v4.6). The substance is furthermore characterised by a high adsorption potential (log 8.34, MCI; KOCWIN v2.00). Based on the results reported for the read across substances, 2,2-bis[[(1-oxoheptyl)oxy]methyl]propane-1,3-diyl bisheptanoate (CAS 25811-35-2) (76 – 96% ; OECD 301B).

Therefore an extensive elimination of the substance in sewage treatment plants is probable. According to the Guidance on information requirements and chemical safety assessment, Chapter R.7b (ECHA, 2012) insoluble chemicals will be extensively removed in in the primary settling tank and fat trap of standard Sewage Treatment Plants (STP) and thus, only limited amounts will get in contact with activated sludge organisms. Due to the high adsorption potential of the substance (log Koc >3) removal from the water column to a significant degree by adsorption to sewage sludge can be expected (Guidance on information requirements and chemical safety assessment, Chapter R.7b, (ECHA, 2012). Therefore the substance concentration in the STP effluent is probably very low. An abiotic degradation of the substance by hydrolysis is not probable due to the predicted half-lives > 1 year of the main components (HYDROWIN v2.00). The substance is not expected to be present in the atmosphere due to the low vapour pressure. Therefore photodegradation is presumably not relevant. Nevertheless the substance is susceptible to indirect photodegradation in air by OH-radicals as indicated by calculated half-lives <24 h for the main substance components (AOPWIN v1.92).

Due to the low water solubility, rapid environmental biodegradation and metabolisation via enzymatic hydrolysis a relevant uptake and bioaccumulation in aquatic organisms is not expected. Enzymatic breakdown will initially lead to the free fatty acid and the free alcohol (e. g. pentaerythritol). From literature it is well known, that these hydrolysis products will be metabolised and excreted in fish effectively (Heymann, 1980; Lech & Bend, 1980; Lech & Melancon, 1980; Murphy & Lutenske, 1990). This is supported by a low calculated BCF/BAF value of 0.895 L/kg ww (BCFBAF v3.01, Arnot-Gobas, including biotransformation, upper trophic). Please refer to IUCLID Section 5.3 for a detailed overview on bioaccumulation .

A detailed reference list is provided in the technical dossier (see IUCLID, section 13) and within CSR.