Hexadecyl (R)-12-hydroxyoleate

Endpoint summary

Description of key information

Oral: LD50 > 2000 mg/kg bw 
Inhalation: LC50 > 5.7 mg/L
Dermal: LD50 > 2000 mg/kg bw

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 adequate, reliable (Klimisch score 2) and consistent studies from reference substances with similar structure and intrinsic properties. Read-across is justified based on common precursors and breakdown products of hydrolysis and consistent trends in environmental fate, ecotoxicological and toxicological profile (refer to the endpoint discussion for further details).
The selected study is thus sufficient 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.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The available information comprises an adequate and reliable study (Klimisch score 2) from a reference substance with similar structure and intrinsic properties. Read-across is justified based on common precursors and breakdown products of hydrolysis and consistent trends in environmental fate, ecotoxicological and toxicological profile (refer to the endpoint discussion for further details).
The selected study is thus sufficient to fulfil the standard information requirements set out in Annex VIII, 8.5, in accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006.

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The available information comprises an adequate and reliable study (Klimisch score 2) from a reference substance with similar structure and intrinsic properties. Read-across is justified based on common precursors and breakdown products of hydrolysis and consistent trends in environmental fate, ecotoxicological and toxicological profile (refer to the endpoint discussion for further details).
The selected study is thus sufficient to fulfil the standard information requirements set out in Annex VIII, 8.5, in accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006.

Additional information

Justification for read-across

Data on the acute oral, inhalation and dermal toxicity of Hexadecyl (R)-12-hydroxyoleate (CAS 10401-55-5) are not available. The assessment of acute toxicity was therefore based on studies conducted with analogue (source) substances as part of a read across approach, which is in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5. For each specific endpoint the source substance(s) structurally closest to the target substance is/are chosen for read-across, with due regard to the requirements of adequacy and reliability of the available data. Structural similarities and similarities in properties and/or activities of the source and target substance are the basis of read-across. A detailed justification for the analogue read-across approach is provided in the technical dossier (see IUCLID Section 13).

Acute oral toxicity

CAS 72576-80-8

The potential to exhibit acute oral toxicity of Hexadecanoic acid, isooctadecyl ester (CAS 72576-80-8) was assessed in a study performed according to OECD 401 (Bouffechoux, 1999). 5 rats/sex were administered 2000 mg/kg bw of the test substance by gavage. No mortality occurred. No clinical signs were observed during the 14-day observation period and the body weights were comparable between the control group and treatment group. A gross pathology examination was not performed. Based on the results of the conducted study, the oral LD50 value is considered to be > 2000 mg/kg bw.

CAS 3234-85-3

Basic data on an acute oral toxicity study are reported from a study performed by Cade (1976) according to a protocol similar to OECD 401. 5 rats/sex/dose were administered 5000 mg/kg bw Tetradecanoic acid, tetradecyl ester (CAS 3234-85-3) as a 50% solution in corn oil by gavage. One male died on Day 4; however, no information regarding the cause of death was reported. No clinical signs were observed in the remaining animals during the 14-day observation period and the body weight gain was within the expected range for this strain and study type. No unusual findings were reported during the macroscopic examination. Based on the results of the study, the oral LD50 value is considered to be > 5000 mg/kg bw.

Acute inhalation toxicity

CAS 26399-02-0

The acute inhalation toxicity of 2-Ethylhexyl oleate (CAS 26399-02-0) was assessed in a study performed according to OECD guideline 436 and under GLP conditions (Van Huygevoort, 2010). 3 rats/sex were administered 5.7 ± 0.4 mg/L (analytical concentration) of the test substance as an aerosol via nose-only exposure for 4 h. The nominal concentration was 15.4 mg/L and the MMAD was 2.5-2.6 µm. No mortality occurred. The animals had a hunched posture on Day 2; no further clinical signs were observed during the 14-day observation period. The body weight gain was within the range that is normal for this strain and study type. No findings were reported during the macroscopic examination. Based on the results of the conducted study, the inhalation LC50 value is considered to be > 5.7 mg/L (analytical concentration).  

Acute dermal toxicity

CAS 3687-46-5

An acute dermal toxicity study (limit test) was performed with Decyl oleate (CAS 3687-46-5) according to OECD guideline 402 and under GLP conditions (Beerens-Heijnen, 2010). 2000 mg/kg bw of the test substance was applied to the skin of 5 Wistar rats/sex under an occlusive dressing for 24 h. No mortality occurred. Piloerection was noted in 2/5 males on Day 1 and chromodacryorrhoea was noted in 3/5 males on Day 1 - 2. No clinical signs were noted in females. The body weight increases were within the range expected for rats used in this type of study and no treatment-related findings were reported during the necropsy and histopathological examination. Focal erythema was observed on the treated skin for up to 4 days during the first week in 4/5 females. Scales or scabs were noted on the treated skin area in 5/5 females and 3/5 males for up to 9 days during Day 7-15 of the observation period. The dermal LD50 value is considered to be > 2000 mg/kg bw.

Overall conclusion for acute toxicity

The reliable data available for the source substances indicate a very low level of acute toxicity following the oral, inhalation and dermal route, as LD50 and LC50 values were greater than the currently applied limit values. Therefore, as the available data did not identify any hazard for acute toxicity, Hexadecyl (R)-12-hydroxyoleate is not expected to be hazardous following acute exposure.

Justification for selection of acute toxicity – oral endpoint
Hazard assessment is conducted by means of read-across from structural analogues. The selected study is the most adequate and reliable study based on the identified similarities in structure and intrinsic properties between the source and target substance and overall quality assessment (refer to the endpoint discussion for further details).

Justification for selection of acute toxicity – inhalation endpoint
Hazard assessment is conducted by means of read-across from a structural analogue. The selected study is the most adequate and reliable study based on the identified similarities in structure and intrinsic properties between the source and target substance and overall quality assessment (refer to the endpoint discussion for further details).

Justification for selection of acute toxicity – dermal endpoint
Hazard assessment is conducted by means of read-across from a structural analogue. The selected study is the most adequate and reliable study based on the identified similarities in structure and intrinsic properties between the source and target substance and overall quality assessment (refer to the endpoint discussion for further details).

Justification for classification or non-classification

According to Article 13 of Regulation (EC) No. 1907/2006 "General Requirements for Generation of Information on Intrinsic Properties of substances", information on intrinsic properties of substances may be generated by means other than tests e.g. from information from structurally related substances (grouping or read-across), provided that conditions set out in Annex XI are met. Annex XI, "General rules for adaptation of this standard testing regime set out in Annexes VII to X” states that “substances whose physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity may be considered as a group, or ‘category’ of substances. This avoids the need to test every substance for every endpoint". Since the analogue concept is applied to Hexadecyl (R)-12-hydroxyoleate (CAS 10401-55-5), data will be generated from information on reference source substance(s) to avoid unnecessary animal testing. Additionally, once the analogue read-across concept is applied, substances will be classified and labelled on this basis.

Therefore, based on the target substance information and analogue read-across approach, the available data on acute toxicity do not meet the classification criteria according to Regulation (EC) 1272/2008 and are therefore conclusive but not sufficient for classification.