Fatty acids, rape-oil, mixed esters with 1,4:3,6-dianhydro-d-glucitol, sorbitan and sorbitol

Short-term toxicity to aquatic invertebrates

Description of key information

Taking all available information into account the substance is unlikely to pose a risk for aquatic invertebrates.

Additional information

Since no studies investigating the short-term toxicity of Fatty acids, rape-oil, mixed esters with 1,4:3,6-dianhydro-d-glucitol, sorbitan and sorbitol (CAS 93334-10-2) to aquatic invertebrates are available, in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5 a read across to the structurally related analogue substances sorbitan stearate (CAS 1338-41-6), sorbitan oleate (CAS 1338-43-8) and Sorbitan, (Z)-9-octadecenoate (2:3) (CAS 8007-43-0) was conducted.
This read-across is justified as all substances share a comparable structure. 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 sorbitan stearate (CAS 1338-41-6) is characterized as a mono-, di- and tri-ester of sorbitan with C16-C18 fatty acids. Sorbitan oleate (CAS 1338-43-8) consists of sorbitan and C18 unsaturated fatty acid, whereas Sorbitan, (Z)-9-octadecenoate (2:3) (CAS 8007-43-0) is an ester (mono, di and tri) of sorbitan, sorbitol and 1,4:3,6-dianhydro-d-glucitol with C18 unsaturated fatty acid. Further justification is given within the endpoint summary 6.1 and within the analogue justification in section 13.

The first study with the marine copepod Acartia tonsa was performed according to a proposal for ISO guideline 14669 and GLP conditions with the source substance sorbitan oleate (CAS 1338-43-8) (Hudson, 1999). A. tonsa was exposed to nominal concentrations up to 10000 mg/L. Test concentrations were prepared as Water Accommodated Fractions (WAFs). No effects were recorded after 48 h and an LL50 of > 10000 mg/L was derived.

The second study with the freshwater species Daphnia magna was performed according to a standard method (Circular on Test Methods of New Chemical Substances) and GLP with the source substance sorbitan stearate (CAS 1338-41-6; Ministry of the Environment, Government of Japan, 2006). D. magna was exposed to filtered test solutions with nominal concentrations up to 1000 mg/L. No effects were recorded at the end of the study resulting in an EL50 (48 h) > 1000 mg/L based on mobility.

The third study with the source substance Sorbitan, (Z)-9-octadecenoate (2:3) (CAS 8007-43-0) was performed according to the OECD Guideline 202 and GLP (Hudson, 2003). The test organism Acartia tonsa was exposed to the test substance in a static system for 48 h, at nominal test concentrations of 1000, 1800, 3200, 5600 and 10000 mg/L. Immobilisation was observed at the highest loading rate, and an LL50 (48 h) of 7756 mg/L was derived. Although the test solutions were prepared as water accommodated fractions (WAF), physical effects caused by undissolved test material cannot be excluded. The sudden increase in mortality from 0% at concentrations up to 1000 - 5600 mg/L to 100% at 10000 mg/L, is more likely to be caused by the amount of undissolved test material in the test solution, leading to immobilisation of the daphnia, rather than a systemic toxic effect. 

Based on the results from structurally related read-across substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5) it can be concluded that Fatty acids, rape-oil, mixed esters with 1,4:3,6-dianhydro-d-glucitol, sorbitan and sorbitol will not exhibit short-term effects to aquatic invertebrates up to the limit of water solubility.