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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

One experimental study is available, in which the ready biodegradability of the target substance Fatty acids, C18-unsaturated, 2-hexyldecyl ester was investigated according to OECD guideline. However, since the key study conducted with the target substance was not GLP compliant, an additional read-across to a study conducted with the structurally and chemically closely related source substance Fatty acids, C16 - 18, 2-hexyldecyl esters (CAS 101227-09-2) was performed in order to support the key findings and to fulfill the standard information requirements laid down in Annex VII of the REACh Regulation (EC) No. 1907/2006. The source substance is characterized by similar fatty acid and alcohol components and is therefore considered a suitable representative for the assessment of the ready biodegradability of the target substance. Read-across was conducted in accordance with Regulation (EC) No 1907/2006 Annex XI, 1.5 and a detailed justification of the analogue approach is provided in IUCLID section 13.

The target substance Fatty acids, C18-unsaturated, 2-hexyldecyl esteris characterized by high molecular weight (> 500 g/mole), very low water solubility (< 0.56 µg/L), a low estimated vapour pressure (< 0.0001 Pa at 20 °C, QSAR, ARChem SPARC v4.6), and a high estimated log Kow (QSAR, Vega v1.1.3). Experimental results from a standard biodegradation study showed that the target substance is readily biodegradable (94.6% within 28 d, OECD 301 B, CO2 evolution), which is confirmed by the read-across study with the source substance Fatty acids, C16 - 18, 2-hexyldecyl esters, CAS 101227-09-2 (90% degradation in 28 d, OECD 301 D). Thus, abiotic degradation via hydrolysis as well as evaporation and indirect photodegradation in air are not relevant environmental pathways.

According to the Guidance on information requirements and chemical safety assessment, Chapter R.7b, readily biodegradable substances can be expected to undergo rapid and ultimate degradation in most environments, including biological Sewage Treatment Plants (STPs) (ECHA, 2017). Due to ready biodegradability and high potential for adsorption, the substance can be effectively removed in conventional STPs by biodegradation and sorption to biomass. Furthermore, the Guidance also states that once insoluble chemicals enter a standard STP, they will be extensively removed in the primary settling tank and fat trap and thus, only limited amounts will come into contact with activated sludge microorganisms. Therefore, only negligible amounts of the substance are expected to be released into the environment through conventional STPs, if at all. Whatever fraction is released into the aquatic environment will undergo extensive biodegradation and will preferentially distribute into the sediment compartment through sorption to organic matter, leading to a rapid reduction of the bioavailability of the substance in water. Thus, the relevant route of uptake in aquatic organisms is expected to predominantly occur by ingestion of particle bound substance, but the bioavailability of the substance is presumably very low based on its physico-chemical properties.


Overall, the available information on the environmental behavior, in combination with data from a similar substance, provide sufficient information to cover the data requirements set out in Regulation (EC) No. 1907/2006, Annex VII.