Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

There are no data available on the biodegradation of Fatty acids, rape-oil, mixed esters with 1,4:3,6-dianhydro-d-glucitol, sorbitan and sorbitol (CAS 93334-10-2). 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 one structurally related 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.

Based on the specification the target substance Fatty acids, rape-oil, mixed esters with 1,4:3,6-dianhydro-d-glucitol, sorbitan and sorbitol is characterized by the alcohol components sorbitol, sorbitan and 1,4:3,6-dianhydro-d-glucitol esterified as mono (mainly), -di- or tri-ester with mainly fatty acids of C18 and C18 unsaturated. The source substance, selected to cover biodegradation is specified as followed:

-         Sorbitan oleate (CAS 1338-43-8) consists of sorbitan and C18 unsaturated fatty acid.

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

The target substance Fatty acids, rape-oil, mixed esters with 1,4:3,6-dianhydro-d-glucitol, sorbitan and sorbitol (CAS 93334-10-2) is characterised by a low vapour pressure (VP < 0.0001 Pa at 20 °C, SPARC (v4.6)), a low water solubility (832 µg/L ± 208 µg/L at 20 °C, pH=6.3) and a high log Koc indicating a high adsorption potential to soil and sediment particles (log Koc > 3, MCI method, KOCWIN v2.00). Based on the result from the selected source substance, the target substance is readily biodegradable (71.1 - 84.5% after 28 d (OECD 301B). Thus, it is expected that an extensive elimination of the substance in sewage treatment plants will occur. In the case insoluble chemicals enter a standard Sewage Treatment Plant (STP), they will be extensively removed in the primary settling tank and fat trap and thus, only limited amounts will get in contact with activated sludge organisms, according to the Guidance on information requirements and chemical safety assessment, Chapter R.7b (ECHA, 2012b). As a result of the high adsorption potential of the substance (log Koc > 3, MCI method, KOCWIN v2.00) a 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, 2012b). In conclusion, the concentration of the substance in conventional STP effluents is presumably marginal. Abiotic degradation via hydrolysis is considered as not relevant for the substance. Moreover, the substance is not volatile (vapour pressure < 0.0001 Pa at 20 °C) and thus evaporation to the air and subsequent transport through the atmosphere to other environmental compartments is not likely. However, if Fatty acids, rape-oil, mixed esters with 1,4:3,6-dianhydro-d-glucitol, sorbitan and sorbitol is released into air, the substance is susceptible to indirect photodegradation in air by OH-radicals as half-lives of less than 24 hours were calculated for the main components of the substance (Müller, 2014).

Based on the low water solubility and metabolism via enzymatic hydrolysis of the substance a relevant uptake and bioaccumulation in aquatic organisms is not expected. The test substance will be hydrolysed and the cleavage products can be further metabolized. In conclusion, bioaccumulation and biomagnification through the food chain of the substance is not expected. Please refer to IUCLID Section 5.3 for a detailed overview on bioaccumulation of Fatty acids, rape-oil, mixed esters with 1,4:3,6-dianhydro-d-glucitol, sorbitan and sorbitol.

As it can be seen in the data matrix of the analogue justification in IUCLID Section 13, all reliable data from the target and the source substance support the read-across by showing a consistent pattern of results.