4-(2,6,6-trimethylcyclohex-2-ene-1-yl)-but-3-ene-2-one

Endpoint summary

Description of key information

Skin Irritation:

Preliminary irritation tests were performed for the test chemical in guinea pigs to determine the concentration suitable for the sensitization study[injection challenge concentration (ICC) and application challenge concentration(ACC)]. In the preliminary irritation study, 4 Albino Hartley guinea pigs of the same sexwereinjected intradermally on the shaved flanks with 0.1 ml aliquots of a range of concentrations of tests material in a suitable solvent. The reactions were examined for size (two largest diameters), erythema and oedema 24 h later and the concentration giving slight but perceptible irritationwith no oedema was selected as the injection challenge concentration (ICC).0.1 ml of the test material in arange of concentrations in a suitable solvent were applied in small circular areas to the shaved flanks of 4 guinea pigs of the same sex.The reactions were examined for erythema 24 hours later and the highest concentration which caused no irritation was selected as the application challenge concentration (ACC). No signs of erythema and edema were observed at 0.1% ICC and 30% ACC concentrations. Hence, the test chemical was considered to be non-irritating to guinea pigs in the preliminary irritation tests performed for the sensitization study.

Eye Irritation:

An eye irritation test was conducted in three rabbits to assess the ocular irritation potential of the test chemical. A 0.1 ml aliquot of 100% and 5% the test chemical in DEP was instilled into one eye of each of three rabbits with no further treatment. The untreated eye served as a control. Observations for irritation were made immediately after instillation and again at 1, 2, 4, 24, 48 and 72 h after instillation. Very slight conjunctival irritation was observed in all three rabbits at instillation, which cleared by 24 hours. The instillation of test chemical did not cause any ocular irritation in 3 rabbits after 72 hours of observation. The test chemical can be considered as a non irritant to rabbit eyes.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

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 publication

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

Preliminary irritation study of the test chemical was performed in guinea pigs to determine the concentration suitable for the sensitization study.

GLP compliance:

not specified

Species:

guinea pig

Strain:

Hartley

Details on test animals or test system and environmental conditions:

Details on test animals:
- Sex: Male/female
- Weight at study initiation: 450 g
- Housing: Housed in wire mesh cages in pairs of the same sex
- Diet (e.g. ad libitum): Pelleted guinea pig diet, cabbage and hay ad libitum
- Water (e.g. ad libitum): water ad libitum

Type of coverage:

not specified

Preparation of test site:

other: Intradermal application: clipped and shaved flanks Dermal application: shaved flanks

Vehicle:

other: Vehicle used but no detailed information.

Controls:

not specified

Amount / concentration applied:

Amount: 0.1 ml
concentration applied: 30%

Duration of treatment / exposure:

Duration of treatment: 24hours

Observation period:

24 hours

Number of animals:

4 (same sex)

Details on study design:

TEST SITE
- Area of exposure:
Intradermal – shaved flanks
Topical - small circular areas on the clipped, shaved flanks

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

24 h

Reversibility:

not specified

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

no signs of irritation were observed

Interpretation of results:

other: not irritating

Conclusions:

No signs of erythema and edema were observed at 0.1% ICC and 30% ACC concentrations. Hence, the test chemical was considered to be non-irritating on guinea pigs in the preliminary irritation tests performed for the sensitization study.

Executive summary:

Preliminary irritation tests were performed for the test chemical in guinea pigs to determine the concentration suitable for the sensitization study[injection challenge concentration (ICC) and application challenge concentration(ACC)]. In the preliminary irritation study, 4 Albino Hartley guinea pigs of the same sexwereinjected intradermally on the shaved flanks with 0.1 ml aliquots of a range of concentrations of tests material in a suitable solvent. The reactions were examined for size (two largest diameters), erythema and oedema 24 h later and the concentration giving slight but perceptible irritationwith no oedema was selected as the injection challenge concentration (ICC).0.1 ml of the test material in arange of concentrations in a suitable solvent were applied in small circular areas to the shaved flanks of 4 guinea pigs of the same sex.The reactions were examined for erythema 24 hours later and the highest concentration which caused no irritation was selected as the application challenge concentration (ACC). No signs of erythema and edema were observed at 0.1% ICC and 30% ACC concentrations. Hence, the test chemical was considered to be non-irritating to guinea pigs in the preliminary irritation tests performed for the sensitization study.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

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 from peer reviewed journal

Qualifier:

equivalent or similar to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

To assess the ocular irritation potential of the test chemical in rabbits

GLP compliance:

no

Species:

rabbit

Strain:

not specified

Details on test animals or tissues and environmental conditions:

no data

Vehicle:

other: No vehicle for 100% concentration and DEP for 5% concentration

Controls:

yes, concurrent no treatment

Amount / concentration applied:

A 0.1 ml aliquot of 100% and 5% the testchemical in DEP

Duration of treatment / exposure:

not specified

Observation period (in vivo):

1, 2, 4, 24, 48 and 72 h after instillation.

Number of animals or in vitro replicates:

3

Details on study design:

SCORING SYSTEM: no data

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: after instillation

Reversibility:

fully reversible within: 24 hours

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

Very slight conjunctival irritation was observed in all three rabbits at instillation, which cleared by 24 h

Table 1: Summary of the eye irritation studies

Dose	Vehicle	Result
100%	No	No irritation observed
5%	DEP	No irritation observed

 

 

Interpretation of results:

other: not irritating

Conclusions:

Very slight conjunctival irritation was observed in all three rabbits at instillation, which cleared by 24 hours. The instillation of test chemical did not cause any ocular irritation in 3 rabbits after 72 hours of observation. The test chemical can be considered as a non irritant to rabbit eyes

Executive summary:

An eye irritation test was conducted in three rabbits to assess the ocular irritation potential of the test chemical. A 0.1 ml aliquot of 100% and 5% the test chemical in DEP was instilled into one eye of each of three rabbits with no further treatment. The untreated eye served as a control. Observations for irritation were made immediately after instillation and again at 1, 2, 4, 24, 48 and 72 h after instillation. Very slight conjunctival irritation was observed in all three rabbits at instillation, which cleared by 24 hours. The instillation of test chemical did not cause any ocular irritation in 3 rabbits after 72 hours of observation. The test chemical can be considered as a non irritant to rabbit eyes.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin Irritation :

Various studies have been summarized to determine the degree of dermal irritation caused by the test chemical in living organisms. These results include in vivo experimental studies on rabbits, guinea pigs, miniature swine and humans.

Preliminary irritation tests were performed for the test chemical in guinea pigs to determine the concentration suitable for the sensitization study[injection challenge concentration (ICC) and application challenge concentration(ACC)]. In the preliminary irritation study, 4 Albino Hartley guinea pigs of the same sexwereinjected intradermally on the shaved flanks with 0.1 ml aliquots of a range of concentrations of tests material in a suitable solvent. The reactions were examined for size (two largest diameters), erythema and oedema 24 h later and the concentration giving slight but perceptible irritationwith no oedema was selected as the injection challenge concentration (ICC).0.1 ml of the test material in arange of concentrations in a suitable solvent were applied in small circular areas to the shaved flanks of 4 guinea pigs of the same sex.The reactions were examined for erythema 24 hours later and the highest concentration which caused no irritation was selected as the application challenge concentration (ACC). No signs of erythema and edema were observed at 0.1% ICC and 30% ACC concentrations. Hence, the test chemical was considered to be non-irritating to guinea pigs in the preliminary irritation tests performed for the sensitization study.

This is supported by the results of the skin irritation study of the test chemical carried out in 6 Pitman-Moore improved strain miniature swine to determine its skin irritation potential.  The test animals were exposed to single application of 50 mg of neat test chemical on the clipped dorsal skin for 48 hours under occlusion.After 48 hours exposure period, the patches were removed and observations were made. Since the test chemical did not produce any skin reactions after 48 hours, the test chemical was considered to be non irritant to the skin of miniature swine.

The objective of the another study was to assess the irritant and/or corrosive effects of the test chemical after dermal application on the intact skin in Rabbits. The study was conducted according to OECD Guidelines 404. Three healthy young adult female rabbits were used for conducting acute dermal irritation/corrosion study. Body weights were re­corded on day 0 (prior to application) and at termination. Rabbits with good intact skin were selected for the study. The hairs of all the rabbits were clipped at contralateral sites, approximately 24 hours prior to treatment.A dose of0.5 ml of test item (as such) wasappliedto the skin,over an area of approximately 6 x 6 cm clippedof haironone side of rabbits.The other untreated side was kept as control area and0.5 ml of distilled water was applied at this site. At the end of 4 hours, the gauze patch was removed and test item application site was wiped with water without altering the integrity of the epidermis. Initially, the test item was applied to the clipped area of skin of one rabbit. The test site was covered with gauze patch.After 4 hours of exposure in Animal No. 1, there was very Slight erythema (barely perceptible) and No oedema observed at 1 hour of observation. At 24, 48 and 72 hours observation no erythema and oedema was observed in animal No 1.Hence the confirmatory test was conducted on additional two rabbits (No. 2 and 3)to confirm the non irritant nature of the test item. The patch was removed after 4 hours and rabbits were observed for erythema and oedemaat 1, 24, 48 and 72 hours after patch removal, evaluatedand graded as per draize method. In Animals No. 2 and 3 at 1 hour observation after post patch removal, revealed no erythema and oedema. At 24 and 48 and 72 hour observation animals showed no erythema post patch removal. No oedema was observed during the observation period. The overall irritation score of the substance was determined to be 0. Hence, it was concluded that the test chemical was non-Irritating to the skin of Female New Zealand White rabbits under the experimental conditions.

Another dermal irritation study was also carried out in rabbits to assess the irritation potential of the test chemical. Three rabbits received a single dermal application of 5% the test chemical in diethyl phthalate on abraded and intact skin. Untreated skin of the same rabbits served as a control. The skin sites were observed 24 and 48 or 72 h after application for signs of irritation. Application of 5% the test chemical in diethyl phthalate resulted in very slight to well defined erythema on abraded and intact skin of 2 rabbits at 24 hours which cleared by 72 hours. There was very slight edema on abraded and intact skin of 2 rabbits at 24 hours, which cleared by 72 hours. Since the observed effects were fully reversible within 72 hours, the test chemical can be considered to be not irritating to rabbit skin.

 

Considering the results of the in vivo studies, the test chemical can be considered to be not irritating to skin. Comparing the above annotations with the criteria of CLP Regulation, the test chemical can be classified under the category “Not Classified”.

Eye Irritation:

Various studies have been summarized to determine the extent of ocular damage caused by the test chemical in living organisms. These results include in vivo experimental studies on rabbits for the test chemicals.

An eye irritation test was conducted in three rabbits to assess the ocular irritation potential of the test chemical. A 0.1 ml aliquot of 100% and 5% the test chemical in DEP was instilled into one eye of each of three rabbits with no further treatment. The untreated eye served as a control. Observations for irritation were made immediately after instillation and again at 1, 2, 4, 24, 48 and 72 h after instillation. Very slight conjunctival irritation was observed in all three rabbits at instillation, which cleared by 24 hours. The instillation of test chemical did not cause any ocular irritation in 3 rabbits after 72 hours of observation. The test chemical can be considered as a non irritant to rabbit eyes.

This is supported by the results of another Eye irritation study was conducted in rabbits to evaluate the irritation potential of the test chemical. The study was performed according to Draize method. Neat test chemical (0.1 ml) was instilled in to the eyes of 3 rabbits.The untreated eyes served as controls. Animals were observed for effects after 1, 2, 4, 24, 48, and 72 h instillation of the test chemical. Fluorescein was used to check corneal damage.Neat test chemical produced very slight conjunctival irritation in all three rabbits at 0, 1, 2, and 4 hours. No other effects were observed. Hence, the test chemical was considered not irritating to rabbit eyes.

The above studies are further supported by the results of study performed to assess the irritant and/or corrosive effects of the test chemical when exposed by the ocular route in rabbits. The study was performed in accordance with OECD Guidelines 405. 3 New Zealand white rabbits were used for the study. Rabbits free from injury of eye were selected for the study. The eyes of all the rabbits were examined 24 hours prior to treatment. One eye of each rabbit served as control and other as treated. Control eye was left untreated whereas;0.1 ml of test item (as such)was instilled in the other (treated) eye of rabbits.The eye was observed at 1, 24, 48 and 72 hours after test item instillation.Ophthalmoscope was used for scoring of eye lesions. In the initial test,0.1 ml of test itemwas applied into the conjunctival sac of the left eye of Animal No.1. The right eye of the rabbit served as the control. As animal no. 1 showed ocular lesions at 1, 24 and 48 hours observation period. Hence the confirmatory test was conducted on additional two rabbits (Animal No. 2 and 3);0.1 ml of test itemwas instilled into the conjunctival sac of right eye and left eye served as the control. Ocular lesions were seen at 1, 24 and 48 hours in animal no. 2 whereas at 24 and 48 hours in animal no. 3 observation. Untreated eye of the treated rabbits was normal throughout the experimental period of 72 hours. The following grading scores were observed in treated eye of tested rabbits. Observation at 1 hour after instillation of test item revealed: Cornea-No ulceration or opacity in all 3 animals; Area of Opacity-Zero in all the animals;Iris:Normal in all the animals.Conjunctivae -Some blood vessels definitely hyperaemic (injected) in animal no. 1 and 2 whereas animal no.3 showed no ocular lesion;Chemosis:No swelling (Normal) were observed in all the animals. Observation at 24 hours after instillation of test item revealed: Cornea-No ulceration or opacity in all 3 animals; Area of Opacity-Zero in all the animals;Iris:Normal in all the animals.Conjunctivae -Diffuse, crimson color; individual vessels not easily discernible was observed in all the treated animals;Chemosis:Some swelling above normal (includes nictating membranes) was observed in animal number 1 and no swelling was observed in animal number 2 and 3. At 24 hours observation the rabbits were examined for corneal epithelium cell damage using sodium fluorescein strips and noticed 40 % and 15 % damage in animal no 1 and 2 whereas no damage was seen in animal no. 3. animals.Conjunctivae -blood vessels were normal in all the animals;Chemosis:No swelling was observed in all the animals. Observation at 48 and 72 hours after instillation of test item revealed: Cornea-No ulceration or opacity in all the animals; Area of Opacity-Zero in all the animals;Iris:Normal in all the animals. The individual mean score for Animal Nos. 1, 2 and 3 at 24, 48, 72 hours for Corneal opacity, iris, conjunctiva, chemosis were found  0.00, 0.00, 1.00; 0.33; 0.00, 0.00; 1.00, 0.00 and 0.00, 0.00, 1.00, 0.00,  respectively. Under the experimental conditions, the test chemical was assessed to be not irritating to eyes of rabbits.

Considering the results of the in vivo studies, the test chemical can be considered to be not irritating to eyes. Comparing the above annotations with the criteria of CLP Regulation, the test chemical can be classified under the category “Not Classified”.

Justification for classification or non-classification

Available studies for the test chemical indicate that the test chemical lacks the potential to cause any irritation to eyes and skin. Hence, the test chemical can be considered to be not irritating to eyes and skin. It can further be classified under the category "Not Classified” as per CLP regulation.