branched-nonyl 3,5,5 trimethylhexanoate

Endpoint summary

Description of key information

Oral: based on a weight of evidence approach, no hazard was identified since all available data showed LD50 values > 2000 mg/kg bw.
Inhalation: no study available
Dermal (OECD 402), rat: LD50 > 2000 mg/kg bw/day (based on read-across from CAS 3687-46-5)

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 functional groups, common precursors/breakdown products and similarities in physicochemical and toxicological properties (refer to endpoint discussion for further details). However, the information from these independent sources is consistent and provides sufficient weight of evidence for hazard assessment leading to an endpoint conclusion in accordance with Annex XI, 1.2, of Regulation (EC) No 1907/2006. Therefore, the available information as a whole is 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 study available

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 substances with similar structure and intrinsic properties. Read-across is justified based on common functional groups, common precursors/breakdown products and similarities in physicochemical and toxicological properties (refer to 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 grouping of substances and read-across

There are no data available on the acute toxicity of isononyl isononanoate. In order 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, 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	Acute toxicity oral	Acute toxicity inhalation	Acute toxicity dermal
(previously 42131-25-9) (a)	Isononyl isononanoate	ca. 285	WoE: RA: CAS 10233-13-3 RA: CAS 59219-71-5 RA: CAS 111937-03-2	Waiving	RA: CAS 3687-46-5
10233-13-3 (b)	Isopropyl laurate	242.41	Experimental result: LD50 >5000 mg/kg bw	Experimental result LC50 >5.3 mg/L air (analytical)	--
59219-71-5	3,5,5-trimethylhexyl 3,5,5 -trimethylhexanoate	284.48	Experimental result: LD50 >4350 mg/kg bw	--	--
111937-03-2	Isononanoic acid, C16-18 alkyl esters	382.66; 410.72	Experimental result: LD50 >5000 mg/kg bw, (mouse) LD50 >17010 mg/kg bw (rat)	--	--
3687-46-5	Decyl oleate	422.73	Experimental result: LD50 >2000 mg/kg bw, mouse	--	Experimental result: LD50 >2000 mg/kg bw)

(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 isononyl isononanoate.

A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

 

Discussion

Acute oral toxicity

CAS 10233-13-3

An acute oral toxicity study (limit test) with isopropyl laurate (CAS 10233-13-3) was performed according a protocol similar to OECD 401 (Dufour, 1991). A group of 5 female NMRI EOPS mice received single oral doses of 5000 mg/kg bw. No mortalities were observed during the 6-day study period. No signs of clinical toxicity were reported. The animals showed the expected gain in body weight. The acute oral LD50 in mice was considered to be > 5000 mg/kg bw.

CAS 59219-71-5

The acute oral toxicity of 3,5,5-trimethylhexyl 3,5,5-trimethylhexanoate (CAS 59219-71-5) was assessed an study performed according a protocol similar to OECD 401 (Masson, 1986). 5 female NMRI EOPS mice were administered 5 mL/kg bw test substance by gavage. Limited data was given and no individual results were reported. There was no mortality and no clinical signs were observed. The acute oral LD50 was set at > 5 mL/kg bw, equivalent to 4350 mg/kg bw (based on the density 0.87 g/cm3).

CAS 111937-03-2

In a study comparable to OECD 401, 5 female mice were administered 5000 mg/kg bw isononanoic acid, C16-18 alkyl esters (CAS 111937-03-2) (Dufour, 1991). No mortality occurred. No clinical signs were observed and the body weight was not affected during the 7-day observation period. No necropsy examinations were performed at sacrifice. The acute oral LD50 was considered to be > 5000 mg/kg bw.

In a study performed by Potokar (1970), 10 male rats/dose were administered 10 mL/kg bw isononanoic acid, C16-18 alkyl esters as a 50% solution of the test substance in olive oil and 19.9 mL/kg bw of the undiluted test substance (equivalent to 8.55 and 17.01 g/kg bw, respectively). No mortality occurred, and no clinical signs were reported during the 7-day observation period. Based on the limited data available, the acute oral LD50 was considered to be > 17.01 g/kg bw.

Acute inhalation toxicity

This information is not available.

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 (Beerens-Heijnen, 2010). 2000 mg/kg bw of the test substance was applied to the skin of 5 Wistar rats/sex/dose under an occlusive dressing for 24 hours. No mortality occurred. Piloerection and/ or chromodacryorrhea were noted in all males on Day 1 and/or 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. Erythema was observed on the treated skin for up to 4 days during the first week in 3/5 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 acute dermal LD50 is considered to be > 2000 mg/kg bw.

Conclusions for acute toxicity

No acute toxicity data is available for isononyl isononanoate. Therefore, assessment of acute toxicity via the oral and dermal route is conducted by means of read-across. No mortality was observed in acute oral toxicity studies performed with the analogue substances isopropyl laurate (CAS 10233-13-3), 3,5,5-trimethylhexyl 3,5,5-trimethylhexanoate (CAS 59219-71-5) and isononanoic acid, C16-18 alkyl esters (CAS 111937-03-2) (Dufour, 1991; Dufour, 1991; Masson, 1986; Potokar; 1970). Based on the results of these studies, the overall oral acute LD50 is > 4350 mg/kg bw. In an acute dermal toxicity study performed with the analogue substance decyl oleate (CAS 3687-46-5), no mortality was observed and the acute dermal LD50 was considered to be > 2000 mg/kg bw (Beerens-Heijnen, 2010).

No information is available for acute inhalation toxicity, since human exposure by inhalation is unlikely given the low vapour pressure (0.004-0.045 Pa at 20 °C) and uses of isononyl isononanoate.

Justification for selection of acute toxicity – oral endpoint
Hazard assessment is conducted by means of read-across from structural analogues and based on the weight of evidence from all available studies.

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 source and target substance and overall quality assessment (refer to the endpoint discussion for further details).

Justification for classification or non-classification

Based on read-across from the structurally similar substances, the available data on oral and dermal toxicity do not meet the classification criteria according to Regulation (EC) 1272/2008 or Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.

There are no data available on acute inhalation toxicity.