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Administrative data

Description of key information

Acute toxicity: oral

LD50 was considered to be 2432.88 mg/kg bw (2031.12 - 2923.92) when rats were treated with 2-isopropyl-5-methylcyclohexanone orally.

Acute toxicity: inhalation

The study need not be conducted because exposure of humans via inhalation is not 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.

Acute toxicity: dermal

LD50 was considered to be > 5000 mg/kg bw when rabbits were treated with 2-isopropyl-5-methylcyclohexanone by dermal application. 

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records
Reference
Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Justification for type of information:
Data is from peer-reviewed journal
Reference:
Composition 0
Qualifier:
according to
Guideline:
other: as below
Principles of method if other than guideline:
Acute oral toxicity study of 2-isopropyl-5-methylcyclohexanone in rats
GLP compliance:
not specified
Test type:
other: No data
Limit test:
no
Test material information:
Composition 1
Specific details on test material used for the study:
- Name of test material (as cited in study report): 2-isopropyl-5-methylcyclohexanone
- Molecular formula (if other than submission substance): C10H18O
- Molecular weight (if other than submission substance): 154.2512 g/mole
- Substance type: Organic
- Physical state: Liquid
Species:
rat
Strain:
not specified
Sex:
not specified
Details on test animals and environmental conditions:
No data available
Route of administration:
oral: unspecified
Vehicle:
not specified
Details on oral exposure:
No data available
Doses:
2432.88 mg/kg bw
No. of animals per sex per dose:
No data available
Control animals:
not specified
Details on study design:
No data available
Statistics:
No data available
Preliminary study:
No data available
Sex:
not specified
Dose descriptor:
LD50
Effect level:
ca. 2 432.88 mg/kg bw
Based on:
test mat.
95% CL:
2 031.12 - 2 923.92
Remarks on result:
other: 50% mortality observed
Mortality:
50% mortality observed in treated rats at 2432.88 mg/kg bw
Clinical signs:
No data available
Body weight:
No data available
Gross pathology:
No data available
Other findings:
No data available
Interpretation of results:
GHS criteria not met
Conclusions:
LD50 was considered to be 2432.88 mg/kg bw (2031.12 - 2923.92) when rats were treated with 2-isopropyl-5-methylcyclohexanone orally.
Executive summary:

In a acute oral toxicity study, rats were treated with 2-isopropyl-5-methylcyclohexanone in the concentration of 2432.88 mg/kg bw orally. 50% mortality observed in treated rats at 2432.88 mg/kg bw. Therefore, LD50 was considered to be 2432.88 mg/kg bw (2031.12 - 2923.92) when rats were treated with 2-isopropyl-5-methylcyclohexanone orally.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
2 432.88 mg/kg bw
Quality of whole database:
Data is Klimisch 2 and from peer reviewed journal

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:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Justification for type of information:
Data is from peer-reviewed journal
Reference:
Composition 0
Qualifier:
according to
Guideline:
other: No data
Principles of method if other than guideline:
Acute dermal toxicity study of 2-isopropyl-5-methylcyclohexanone in Rabbit
GLP compliance:
not specified
Test type:
other: No data
Limit test:
yes
Test material information:
Composition 1
Specific details on test material used for the study:
- Name of test material (as cited in study report): 2-isopropyl-5-methylcyclohexanone
- Molecular formula (if other than submission substance): C10H18O
- Molecular weight (if other than submission substance): 154.2512 g/mole
- Substance type: Organic
- Physical state: Solid
Species:
rabbit
Strain:
not specified
Sex:
not specified
Details on test animals and environmental conditions:
No data available
Type of coverage:
not specified
Vehicle:
not specified
Details on dermal exposure:
No data available
Duration of exposure:
No data available
Doses:
No data available
No. of animals per sex per dose:
No data available
Control animals:
not specified
Details on study design:
No data available
Statistics:
No data available
Preliminary study:
No data available
Key result
Sex:
not specified
Dose descriptor:
LD50
Effect level:
> 5 000 mg/kg bw
Based on:
test mat.
Remarks on result:
other: No mortality observed
Mortality:
No mortality was observed in trreated rabbits at 5000 mg/kg bw
Clinical signs:
No data available
Body weight:
No data available
Gross pathology:
No data available
Other findings:
No data available
Interpretation of results:
GHS criteria not met
Conclusions:
LD50 was considered to be > 5000 mg/kg bw when rabbits were treated with 2-isopropyl-5-methylcyclohexanone by dermal application.
Executive summary:

In an acute dermal toxicity study, rabbits were treated with 2-isopropyl-5-methylcyclohexanone in the concentration of 5000 mg/kg bw orally. No mortality observed in treated rabbits at 5000 mg/kg bw. Therefore, LD50 was considered to be > 5000 mg/kg bw when rabbits were treated with 2-isopropyl-5-methylcyclohexanone by dermal application. 

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
5 000 mg/kg bw
Quality of whole database:
Data is Klimisch 2 and from peer reviewed journal

Additional information

Acute oral toxicity:

In different studies, 2-isopropyl-5-methylcyclohexanone has been investigated for acute oral toxicity to a greater or lesser extent. Often are the studies based on in vivo experiments data in rodents, i.e. most commonly in rats for 2-isopropyl-5-methylcyclohexanone. The predicted data using the OECD QSAR toolbox has also been compared with the experimental studies.

In a study conducted by Opdykeet al(Food and Cosm. Toxicology Vol 14, 1976, Pp 475-476,1976), acute oral toxicity was evaluated in rats by using 2-isopropyl-5-methylcyclohexanone in the concentration of 2432.88 mg/kg bw orally. 50% mortality observed in treated rats at 2432.88 mg/kg bw. Therefore, LD50 was considered to be 2432.88 mg/kg bw (2031.12 - 2923.92) when rats were treated with 2-isopropyl-5-methylcyclohexanone orally.

In another prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, rats were treated with 2-isopropyl-5-methylcyclohexanone orally. The estimated LD50 was considered to be 2200 mg/kg bw when rat were treated with 2-isopropyl-5-methylcyclohexanone orally.

Also it is further supported by another prediction done by SSS (2017) using Danish QSAR, the acute oral toxicity in rats was predicted for 2-isopropyl-5-methylcyclohexanone. LD50 value was estimated to be 2067.4 mg/kg bw for rats for24 hours.

This is further supported by experimental datagiven by U.S. Department of Commerce (9180), rats were treated with 2-isopropyl-5-methylcyclohexanone at 2180 mg/kg bw orally. 50 % mortality observed at 2180 mg/kg bw. Therefore, LD50 was considered to be 2180 mg/kg bw when rat were treated with 2-isopropyl-5-methylcyclohexanone orally.

Thus, based on the above predictions and studies on 2-isopropyl-5-methylcyclohexanone, it can be concluded that LD50 value is greater than 2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 2-isopropyl-5-methylcyclohexanone can be “Not-classified” for acute oral toxicity.

Acute toxicity: inhalation

The study need not be conducted because exposure of humans via inhalation is not 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.

Acute dermal toxicity:

Different studies for the target substance 2-isopropyl-5-methylcyclohexanone [(±)-menthone] and its read across substances were reviewed for acute dermal toxicity endpoint and the same are presented below as a weight of evidence approach:

In an acute dermal toxicity study, cited in Food and Cosmetic Technology Vol 14, pg 475-476 (1976), rabbits were treated with 2-isopropyl-5-methylcyclohexanone in the concentration of 5000 mg/kg bw orally. No mortality observed in treated rabbits at 5000 mg/kg bw. Therefore, LD50 was considered to be > 5000 mg/kg bw when rabbits were treated with 2-isopropyl-5-methylcyclohexanone by dermal application. 

Data from ChemIDplus database indicates the determination of acute dermal toxicity of the structurally similar substance 2-sec-Butyl cyclohexanone (CAS 14765-30-1) was carried out in rabbits. No mortality was observed till the last tested concentration. Hence, the acute dermal LD50 value of the substance2-sec-Butyl cyclohexanone is considered to be > 5000 mg/kg for rabbit skin.

Another study from the same database ChemIdplus states the results of acute dermal toxicity of the other read across substance 2-Cyclohexylcyclohexanone (CAS 90-42-6) in rats. No mortality was observed till the last tested concentration. Hence, the acute dermal LD50 value of the substance 2-sec-Butyl cyclohexanone is considered to be >7800 mg/kg for rat skin.

Based on the above results and by applying weight of evidence approach, it can be concluded that the LD50 value is greater than 2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 2-isopropyl-5-methylcyclohexanone can be considered as “Not-classified” for acute dermal toxicity.

Justification for classification or non-classification

Based on the above available data for target 2-isopropyl-5-methylcyclohexanone (CAS no 1074-95-9) is likely to non hazardous by oral route of exposure and considered to not toxic by oral and dermal route as per the criteria mentioned in CLP regulation.