Fatty acids, C18-unsatd., dimers, hydrogenated, 2-ethylhexyl esters

Endpoint summary

Description of key information

Oral LD50 (OECD 423), rat = 5000 mg/kg bw 
Inhalation LC50 (OECD 436), rat > 5.3 mg/L air (RA CAS 68334-05-4)

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The available information comprises an adequate and reliable study, and is thus sufficient to fulfil the standard information requirements set out in Annex VII, 8.5, of Regulation (EC) No 1907/2006.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The available information comprises adequate, reliable (Klimisch score 2) studies from reference substances with similar structure and intrinsic properties and fromhydrolysis products. Read-across is justified either based on structural similarity or common precursors/breakdown products.

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Justification for grouping of substances and read-across

There are only limited data available on acute toxicity of Fatty acids, C18-unsatd., dimers, hydrogenated, 2-ethylhexyl esters (CAS 68440-06-2). In order to fulfil the standard information requirements set out in Annex VII and VIII, 8.5, in accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006, read-across from structurally related substances 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.

Overview of acute toxicity:

CAS	Chemical name	Molecular weight [g/mol]	Acute toxicity Oral	Acute toxicity Inhalation	Acute toxicity Dermal
68440-06-2 (a)	Fatty acids, C18-unsatd., dimers, hydrogenated, 2-ethylhexyl esters	789	Experimental result: LD50 = 5000 mg/kg bw (rat)	RA: CAS 68334-05-4	--
68334-05-4 (b)	Fatty acids, C18-unsaturated, dimers, 2-ethylhexyl esters	673	--	Experimental result: LC50 > 5.3 mg/L (rat)	--

(a) The substance subject to registration is indicated in bold font.

(b) Reference (read-across) substances are indicated in normal font. Lack of data for a given endpoint is indicated by “--“.

The above mentioned substances are considered to be similar on the basis of the structural similar properties and/or activities. The available endpoint information is used to predict the same endpoints for Fatty acids, C18-unsatd., dimers, hydrogenated, 2-ethylhexyl esters (CAS 68440-06-2). A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

Discussion

Acute oral toxicity

CAS 68440-06-2

A key acute oral toxicity study with Fatty acids, C18-unsatd., dimers, hydrogenated, 2-ethylhexyl esters (CAS 68440-06-2) is available and was performed according to OECD TG 423 and in compliance with GLP (Bradshaw, 2015). In this study following the acute toxic class method three female fasted Wistar rats were administered a single dose of 300 mg/kg bw of the test substance (CAS 68440-06-2) whereas another six females received one dose of 2000 mg/kg bw of the test substance in a stepwise procedure via oral gavage. The animals were observed for 14 days after administration. The acute oral LD50 value for females was estimated to be 5000 mg/kg bw according to the flowchart in Annex 2c of OECD TG 423. No mortalities were observed during the study and no signs of systemic toxicity were noted during the observation period in animals treated at a dose level of 300 mg/kg bw. Hunched posture was noted during the day of dosing in all animals treated at a dose level of 2000 mg/kg bw. All animals treated at a dose level of 2000 mg/kg bw appeared normal 1 day after dosing. No abnormalities were noted at necropsy. Based on the study results and according to EU classification criteria, the test substance is not to be classified.

 

Acute inhalation toxicity

CAS 68334-05-4

No data on acute inhalation toxicity is available with Fatty acids, C18-unsatd., dimers, hydrogenated, 2-ethylhexyl esters (CAS 68440-06-2). Therefore, read across from the structural analogue substance Fatty acids, C18-unsaturated, dimers, 2-ethylhexyl esters (CAS 68334-05-4) was applied. A reliable acute inhalation toxicity study was performed with Fatty acids, C18-unsaturated, dimers, 2-ethylhexyl esters (CAS 68334-05-4) according to OECD TG 436 and in compliance with GLP (Huygevoort, 2010). In this study following the acute toxic class method three Crl:WI(Han) rats of each sex were exposed to an aerosol with an analytical concentration of 5.3 mg/L of the test substance for 4 hours in an nose-only inhalation exposure chamber. No mortalities or any abnormal clinical signs were reported during the exposure or within the 14 days observation period. Additionally body weight gain in males and females was within the range expected for rats of this strain and age used in this type of study and no abnormalities were found at macroscopic post mortem examination of the animals. The acute inhalation LC50 value was calculated to be greater than 5.3 mg/L. Based on the results of the study and according to EU classification criteria, the test substance is not to be classified.

Justification for selection of acute toxicity – oral endpoint
The reliable GLP compliant OECD Guideline study was chosen.

Justification for selection of acute toxicity – inhalation endpoint
Hazard assessment is conducted by means of read-across from structural analogues/surrogates. All available studies are adequate and reliable based on the identified similarities in structure and intrinsic properties between source and target substances and overall quality assessment.

Justification for classification or non-classification

The available data on acute toxicity of Fatty acids, C18-unsatd., dimers, hydrogenated, 2-ethylhexyl esters do not meet the criteria for classification according to Regulation (EC) 1272/2008 and are therefore conclusive but not sufficient for classification.