(Z)-N-octadecyldocos-13-enamide

Endpoint summary

Description of key information

Oral: RA-A CAS 16260-09-6 and CAS 13276-08-9, OECD 401, rat: LD50 > 2400 mg/kg bw

Dermal: RA-A CAS 16260-09-6, OECD 402, rat: LD50 > 2000 mg/kg bw

Inhalation: no study available

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Remarks:

Summary of available data used for the endpoint assessment of the target substance

Adequacy of study:

key study

Justification for type of information:

refer to the analogue justification provided in IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 400 mg/kg bw

Based on:

test mat.

Remarks on result:

other: Source 13279-08-9 and 16260-09-6, Notox C.V., 1986a,b

Interpretation of results:

other: CLP/EU GHS criteria are not met, no classification required according to Regulations (EC) No 1272/2008.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

GLP guideline studies with structurally related substances according to the criteria of Regulation (EC) No 1907/2006. Annex XI, paragraph 1.5.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

refer to the analogue justification provided in IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: Source 16260-09-6, Harlan Laboratories Ltd., 2012

Interpretation of results:

other: CLP/EU GHS criteria are not met, no classification required according to Regulations (EC) No 1272/2008.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

GLP guideline study with a structurally related substance according to the criteria of Regulation (EC) No 1907/2006. Annex XI, paragraph 1.5.

Additional information

There is no data available on the acute toxicity of (Z)-N-octadecyldocos-13-enamide (CAS 10094-45-8). In order to fulfil the standard information requirements set out in Annex VII and VIII, 8.5, and in accordance with Annex XI, 1.5 of Regulation (EC) No 1907/2006, read-across from structurally related substances was conducted in accordance with the Read-Across Assessment Framework (RAAF) (ECHA, 2017).

A detailed justification for the analogue approach is provided in the technical dossier (see IUCLID section 13.2).

 

Oral

There are two studies available for the acute oral toxicity of the structurally related substances (Z)-N-octadec-9-enylhexadecan-1-amide (CAS 16260-09-6) and N-octadecylstearamide (CAS 13276-08-9), which were used for read-across based on an analogue approach.

The acute oral toxicity of (Z)-N-octadec-9-enylhexadecan-1-amide (CAS 16260-09-6) was investigated in a GLP-conform study performed according to OECD 401 (Notox C.V., 1986b). The test substance diluted in corn oil was administered to 5 Wistar rats per sex at a limit dose of 2400 mg/kg bw by oral gavage. During the 14-day observation period, no mortality and no clinical signs were observed, except for lethargy which was frequently observed among the animals on Day 1 after treatment. The weekly body weight gain of the animal was normal during the study, and no substance-related gross abnormalities were noted at necropsy. Based on these observations, the oral LD50 value in male and female rats was > 2400 mg/kg bw.

In an acute oral toxicity study with N-octadecylstearamide (CAS 13276-08-9) according to OECD 401 performed under identical conditions as described above, oral gavage administration of the test substance in corn oil to 5 male and 5 female Wistar rats at a limit dose of 2400 mg/kg bw did not result in any mortalities, clinical signs of toxicity, changes in body weights and gross pathological findings during the 14-day observation period (Notox C.V., 1986a). Therefore, the oral LD50 value in male and female rats was > 2400 mg/kg bw.

In addition, there are two repeated dose studies available with (Z)-N-octadecyldocos-13-enamide (CAS 10094-45-8) in which male and female rats were treated with the test substance by gavage for approx. 5 weeks and via the diet for 13 weeks, respectively (Covance Laboratories Limited, 2021; Quintiles Toxicology, 1998). Neither study did reveal any adverse effects of repeated oral administration of the test substance demonstrated by NOAELs of≥1000 mg/kg bw/day. Therefore, acute toxicity after oral administration is not expected for (Z)-N-octadecyldocos-13-enamide (CAS 10094-45-8).

 

Inhalation

In accordance with Regulation (EC) 1907/2006, Annex VIII, Section 8.5.2, column 2, testing by the inhalation route is appropriate if exposure of humans via inhalation is likely taking into account the vapour pressure of the substance and/or the possibility of exposure to aerosols, particles or droplets of an inhalable size. The substance (Z)-N-octadecyldocos-13-enamide is a solid with very low vapour pressure (4.9E-05 Pa at 20 °C) and does not contain respirable particles in a significant amount. Thus, exposure of humans via inhalation is unlikely. Therefore, testing for acute toxicity by the inhalation route is not appropriate and should be avoided for reasons of animal welfare. In addition, reliable data for acute toxicity via the oral and dermal route is available for structurally related substances according to Regulation (EC) No 1907/2006, Annex XI, article 1.5.

 

Dermal

A reliable study on the acute dermal toxicity of the structurally related substance (Z)-N-octadec-9-enylhexadecan-1-amide (CAS 16260-09-6) is available, which is used for read-across based on the analogue approach.

An acute dermal toxicity study with (Z)-N-octadec-9-enylhexadecan-1-amide (CAS 16260-09-6) was performed according to OECD 402 and under conditions of GLP (Harlan Laboratories Ltd., 2012). Five RccHan:WIST rats per sex were exposed to the test substance diluted in archis oil at a limit dose of 2000 mg/kg bw for 24 h under semiocclusive dressing. During the 14-day observation period, no mortality and clinical signs of toxicity were observed, and no gross pathological changes were noted at necropsy. All animals showed the expected body weights during the study, except for one male which showed bodyweight loss during the first week but expected gain in bodyweight during the second week. Very slight erythema was noted at the test sites of 4/5 females (score 1) which abated after 5 days in 3 females and after 8 days in the fourth. There were no signs of dermal irritation noted at the test sites of the remaining animals. Based on the results of this study, a dermal LD50 value > 2000 mg/kg bw was derived for male and female rats.

 

Based on the available data on acute oral and dermal toxicity of the structural analogues, it can be concluded that (Z)-N-octadecyldocos-13-enamide (CAS 10094-45-8) does not exert acute toxicity via the oral and dermal route, either.

Justification for classification or non-classification

The available data on the acute toxicity of (Z)-N-octadec-9-enylhexadecan-1-amide (CAS 16260-09-6) and N-octadecylstearamide (CAS 13276-08-9), which are structurally related substances to (Z)-N-octadecyldocos-13-enamide (CAS 10094-45-8) according to the criteria of Regulation (EC) No 1907/2006, Annex XI, 1.5, do not meet the criteria for classification according to Regulation (EC) No 1272/2008; therefore, (Z)-N-octadecyldocos-13-enamide (CAS 10094-45-8) is not expected to exert acute toxicity, either, and the data are conclusive but not sufficient for classification.