(+)-neomenthol

Endpoint summary

Description of key information

Skin Irritation:

Based on the available data for the structurally similar read across substances and applying the weight of evidence approach, it can be concluded that the target chemical will also tend to behave in a similar that of the read across substances. Therefore, (+)-Neomenthol was estimated to be irritating to skin.Comparing the above annotations with the criteria of CLP regulation,(+)-Neomenthol can be classified under the category “Category 2”.

Eye Irritation:

Based on the available data for the structurally similar read across substances and applying the weight of evidence approach, it can be concluded that the target chemical will also tend to behave in a similar that of the read across substances. Therefore, (+)-Neomenthol was estimated to be not irritating to eyes.Comparing the above annotations with the criteria of CLP regulation,(+)-Neomentholcan be classified under the category “Not Classified”.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

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

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Weight of evidence approach based on structurally similar substances

Justification for type of information:

Weight of evidence approach based on structurally similar substances

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

other: Weight of evidence approach based on structurally similar substances

Principles of method if other than guideline:

Weight of evidence approach based on structurally similar substances

GLP compliance:

not specified

Specific details on test material used for the study:

Name of the test chemical: (1S,2S,5R)-5-methyl-2-propan-2-ylcyclohexan-1-olCommon Name: (+)-NeomentholMolecular Formula: C10H20OMolecular Weight: 156.269 g/molSubstance Type: OrganicPhysical State: Solid

Species:

rabbit

Strain:

not specified

Type of coverage:

other: 1. open, 2. occlusive

Preparation of test site:

other: 1. hairless, 2. intact and abraded skin

Vehicle:

unchanged (no vehicle)

Controls:

not specified

Amount / concentration applied:

1. 0.05 ml2. 5 ml/kg

Duration of treatment / exposure:

1.The dosing was repeated between 5 and 10 times2. 24 hours

Observation period:

1. 2 weeks2. 24 hours

Number of animals:

1. 52. 4

Details on study design:

The study is based on the weight of evidence approach based on structurally similar chemicals

Irritation parameter:

overall irritation score

Basis:

mean

Reversibility:

not specified

Remarks on result:

positive indication of irritation

Irritant / corrosive response data:

Signs of irritation observed

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Conclusions:

Based on the available data for the structurally similar read across substances and applying the weight of evidence approach, it can be concluded that the target chemical will also tend to behave in a similar that of the read across substances. Therefore, (+)-Neomenthol was estimated to be irritating to skin.Comparing the above annotations with the criteria of CLP regulation,(+)-Neomenthol can be classified under the category “Category 2”.

Executive summary:

Based on the available studies for the structurally similar read across chemicals, weight of evidence approach was applied to assess the dermal irritation potential of (+)-Neomenthol

The dermal irritation potential of the structurally similar chemical was assessed in rabbits. Hairless sites on the skin of 5 White rabbits were intradermally injected with 0.05ml of the test chemical. The dosing was repeated between 5 and 10 times. Gross examinations were made at 24 and 48 hours, at 1 and 2 weeks and in some cases 1 month following dosing. Microscopic examination of the skin was performed after the gross examination.

Moderate reactions characterized by polymorphonucelar leukocytes, and plasma cells(without necrosis) were noted in 3 rabbits. Severe reactions as well as necrosis were noted in the other 2 rabbits.

Hence, the test chemical can be considered to be a skin irritant.

This is supported by the results of another dermal irritation study performed in rabbits to assess the irritation potential of structurally similar chemical. 5 ml/kg undiluted test chemical was applied to the intact and abraded skin of 4 rabbits under occlusive conditions for 24 hours. The readings for dermal reactions were taken after patch removal. Mild erythema was observed at 24 hours, but no edema. Hence, the test chemical can be considered to be irritating to rabbit skin.

Based on the available data for the structurally similar read across substances and applying the weight of evidence approach, it can be concluded that the target chemical will also tend to behave in a similar that of the read across substances. Therefore, (+)-Neomenthol was estimated to be irritating to skin.Comparing the above annotations with the criteria of CLP regulation,(+)-Neomenthol can be classified under the category “Category 2”.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin Irritation:

Based on the available studies for the structurally similar read across chemicals, weight of evidence approach was applied to assess the dermal irritation potential of (+)-Neomenthol

The dermal irritation potential of the structurally similar chemical was assessed in rabbits.

Hairless sites on the skin of 5 White rabbits were intradermally injected with 0.05ml of the test chemical. The dosing was repeated between 5 and 10 times. Gross examinations were made at 24 and 48 hours, at 1 and 2 weeks and in some cases 1 month following dosing. Microscopic examination of the skin was performed after the gross examination.

Moderate reactions characterized by polymorphonucelar leukocytes, and plasma cells(without necrosis) were noted in 3 rabbits. Severe reactions as well as necrosis were noted in the other 2 rabbits.

Hence, the test chemical can be considered to be a skin irritant.

This is supported by the results of another dermal irritation study performed in rabbits to assess the irritation potential of structurally similar chemical. 5 ml/kg undiluted test chemical was applied to the intact and abraded skin of 4 rabbits under occlusive conditions for 24 hours. The readings for dermal reactions were taken after patch removal. Mild erythema was observed at 24 hours, but no edema. Hence, the test chemical can be considered to be irritating to rabbit skin.

Based on the available data for the structurally similar read across substances and applying the weight of evidence approach, it can be concluded that the target chemical will also tend to behave in a similar that of the read across substances. Therefore, (+)-Neomenthol was estimated to be irritating to skin.Comparing the above annotations with the criteria of CLP regulation,(+)-Neomenthol can be classified under the category “Category 2”.

Eye Irritation:

Based on the available studies for the structurally similar read across chemicals, weight of evidence approach was applied to assess the ocular irritation potential of (+)-Neomenthol

An eye irritation study was conducted on rabbits to assess the degree of eye irritancy caused by the structurally similar according to Draize method.

The test substance was initially applied in 10, 20 and 30 % solution. The eyes of 4 animals were rinsed 1 minute after application with physiological saline, substance remained in the eyes of 4 animals. In a second step animals were treated with concentration of 40, 50 and 60 %.

No signs of eye irritation were observed. Hence, the chemical was considered to be not irritating to the eyes of rabbits.

This is supported by the results of another ocular irritation study performed on rabbits to determine the degree of irritation caused by the structurally similar chemical.

Undiluted 0.1 ml of the test chemical was instilled in the right eye of 6 New Zealand White rabbits. The untreated left eye served as control. Reactions were scored as per the Draize method against the control, on days 1–8.

The mean irritation scores of the test group were 6.0 (24-h), 2.0 (48-h), 0.3 (96-h), and 0.0 respectively. The effects were fully reversible within 8 days.

Hence, the test chemical can be considered to be not irritating to eyes.

Based on the available data for the structurally similar read across substances and applying the weight of evidence approach, it can be concluded that the target chemical will also tend to behave in a similar that of the read across substances. Therefore, (+)-Neomenthol was estimated to be not irritating to eyes.Comparing the above annotations with the criteria of CLP regulation,(+)-Neomentholcan be classified under the category “Not Classified”.

Justification for classification or non-classification

The results of the experimental studies from the structurally similar read across substances indicate a possibility that (+)-Neomenthol can be irritating to skin but not irritating to eyes.

Hence by applying the weight of evidence approach, (+)-Neomenthol can be considered to be irritating to skin and not irritating to eyes. It can be classified under the category “Not Classified” for eye irritation and “Category 2” for skin irritation as per CLP regulation.