β,4-dimethylcyclohex-3-ene-1-propan-1-al

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 April 2005 and 18 May 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

β,4-dimethylcyclohex-3-ene-1-propan-1-al

EC Number:

229-846-0

EC Name:

β,4-dimethylcyclohex-3-ene-1-propan-1-al

Cas Number:

6784-13-0

Molecular formula:

C11H18O

IUPAC Name:

3-(4-methylcyclohex-3-en-1-yl)butanal

Test material form:

liquid

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: David Percival Ltd, Moston, Sandbach, Cheshire, UK.
- Age at study initiation: twelve to twenty weeks old
- Weight at study initiation: 2.0 to 3.5 kg
- Housing: The animals were individually housed in suspended cages
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 23°C
- Humidity (%): 30 to 70%
- Air changes (per hr): at least fifteen changes per hour
- Photoperiod (hrs dark / hrs light): lighting was controlled by a time switch to give twelve hours continuous light (06:00 to 18:00) and twelve hours darkness

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

0.5 mL

Duration of treatment / exposure:

3 minutes, 1 hour and 4 hours

Observation period:

Approximately one hour following the removal of the patches, and 24, 48 and 72 hours later

Number of animals:

3

Details on study design:

TEST SITE: One rabbit was initially treated. Three suitable sites were selected on the back of the rabbit. At each test site a quantity of 0.5 ml of the test material was introduced under a 2.5 cm x 2.5 cm cotton gauze patch and placed in position on the shorn skin. Each patch was secured in position with a strip of surgical adhesive tape. To prevent the animal interfering with the patches, the trunk of the rabbit was wrapped in an elasticated corset and the animal was returned to its cage for the duration of the exposure period. One patch was removed at each of three time points: 3 minutes, 1 hour and 4 hours after application. After consideration of the skin reactions produced in the first animal, two additional animals were treated with 0.5 ml of test material. One patch was applied to the back of each rabbit, and was allowed to remain in contact with the skin for a period of four hours.

REMOVAL OF TEST SUBSTANCE: Any residual test material was removed by gentle swabbing with cotton wool soaked in distilled water.

OBSERVATION TIME POINTS AND SCORING: Approximately one hour following the removal of the patches, and 24, 48 and 72 hours later, the test sites were examined for evidence of primary irritation and scored.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 2

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 3

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 4

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 14 days

Remarks on result:

other: At day 14 only some desquamation is seen

Results 5

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 14 days

Remarks on result:

other: At day 14 only some desquamation is seen.

Results 6

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 14 days

Remarks on result:

other: At day 14 only some desquamation is seen.

Other effects:

Other skin reactions were a light brown discoloration of the epidermis, desquamation and loss of skin elasticity. One treated skin site appeared normal at the 14-day observation. Desquamation is seen at day 7 with erythema in 2/3 animals. At day 14 only some desquamation is seen, without inflammation.

Any other information on results incl. tables

Individual Skin Reactions Following 4-Hour Exposure:

			Individual Scores - Rabbit Number and Sex
Skin Reaction	Observation	Time				Total
			15 Male	62 Male	63 Male
	1 Hour		1	2	2	(5)
	24 Hours		1	2	2	5
Erythema/Eschar	48 Hours		1	2 Br	2	(5)
Formation	72 Hours		1 Le	2BrLe	2Br	5
	7 Days		OD	lD	lD	(2)
	14 Days		OD*	OD*	OD*	0
	1 Hour		0 -	I	1	(2)
	24 Hours		0	1	1	2
	48 Hours		0	1	1	(2)
Oedema Formation
	72 Hours		0	1	1	2
	7 Days		0	0	0	0
	14 Days		0	0	0	0
Sum of24 and 72-hour Readings (S)			14
Primary Irritation Index (S/6)			14/6 = 2.3
Classification			MODERATE IRRITANT

Individual Skin Reactions Following 1-Hour and 3-Minute Exposures:

		Individual Scores - Rabbit Number and Sex
		15 Male
Skin Reaction	Observation Time	1-Hour Exposure	3-Minute Exposure
	1 Hour	1	0
	24 Hours	1	0
Erythema/Eschar	48 Hours	1	0
Formation	72 Hours	1 Le	0
	7 Days	OD	0
	14 Days	OD*	0
	1 Hour	0	0
	24 Hours	0	0
	48 Hours	0	0
Oedema Formation	72 Hours	0	0
	7 Days	0	0
	14 Days	0	0

 () = Total values not used for calculation of primary irritation index

Br= Light brown discolouration of the epidermis

Le = Loss of skin elasticity

D = Moderate desquamation

D* = Slight desquamation

Applicant's summary and conclusion

Interpretation of results:

other: Not a skin irritant in accordance with EU CLP (EC no 1272/2008 and its amendments)

Conclusions:

The test substance is not classified to be a skin irritant under the conditions of the study.

Executive summary:

The study was performed to assess the irritancy potential of Limoxal following single, 3-minute, 1 and 4-hour, semi-occluded applications to the intact rabbit skin according to the OECD Guideline 404 in compliance with GLP.
No corrosive effects noted after the 3-minute and 1-hour semi-occluded applications of test material to intact skin of one rabbit. A single 4 hour semi-occluded application of test material to the intact skin of 3 rabbits resulted in well-defined erythema and very slight to slight edema. The mean erythema and oedema scores over 24, 48 and 72 hours were 1 and 0 for one rabbit and 2 and 1 for other two rabbits. In all cases, erythema was reversible within 14 days and oedema was reversible in 7 days in all the animals. Other skin reactions were a light brown discoloration of the epidermis, desquamation and loss of skin elasticity. One treated skin site appeared normal at the 14-day observation. Desquamation is seen at day 7 with erythema in 2/3 animals. At day 14 only some desquamation is seen, without inflammation. Therefore the substance does not need to be classified for skin irritation.