Cyclohexanecarboxylic acid, 1-(2-ethylbutyl)-

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

November 23, 2010 - December 14, 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study has been performed according to OECD and/or EC guidelines and according to GLP principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

temporary deviations from the minimum level of relative humidity occurred (down to 33%)

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

temporary deviations from the minimum level of relative humidity occurred (down to 33%)

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Deviations:

yes

Remarks:

temporary deviations from the minimum level of relative humidity occurred (down to 33%)

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), 12 Nousan, Notification No 8147, November 2000, including the most recent partial revisions

Deviations:

yes

Remarks:

temporary deviations from the minimum level of relative humidity occurred (down to 33%)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1-(2-ethylbutyl)cyclohexane-1-carboxylic acid

EC Number:

619-508-4

Cas Number:

381209-09-2

Molecular formula:

C13 H24 O2

IUPAC Name:

1-(2-ethylbutyl)cyclohexane-1-carboxylic acid

Details on test material:

- Name of test material (as cited in study report): CAT-Acid
- Stability under test conditions: stable
- Storage condition of test material: at room temperature in the dark
- Density: 0.98 g/mL
- pH (1% in water, indicative range): 5.4-5.2

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: animal no. 2: Charles River France, L’Arbresle Cedex, France; animal no. 1 and 3: Charles River Deutschland, Kisslegg, Germany
- Age at study initiation: at least 6 weeks
- Weight at study initiation: at least 1.0 kg
- Housing: individually housed in labeled cages with perforated floors (Ebeco, Germany, dimensions 67 x 62 x 55 cm) and shelters (Ebeco, Germany, dimensions 40 x 32 x 23 cm)
- Diet (e.g. ad libitum): ad libitum; pelleted diet for rabbits (Global Diet 2030 from Harlan Teklad®, Mucedola, Milanese, Italy)
- Water (e.g. ad libitum): ad libitum; tap water
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18.6 – 19.8ºC
- Humidity (%): 33 - 50%; Temporary deviations from the minimum level of relative humidity occurred. As laboratory historical data do not indicate an effect of the deviations, the study integrity was not adversely affected.
- Air changes (per hr): approximately 15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12 hours artificial fluorescent light and 12 hours darkness per day

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: approximately 24 hours before treatment, the dorsal fur was clipped with electric clippers, exposing an area of approximately 150 square centimeters (10x15 cm)

Vehicle:

unchanged (no vehicle)

Controls:

other: adjacent areas of the untreated skin of each animal served as controls

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL

Duration of treatment / exposure:

4 hours

Observation period:

14 days

Number of animals:

3 females

Details on study design:

TEST SITE
- Area of exposure: the test substance was applied to the skin of one flank, using a metalline patch# of 2x3 cm
- Type of wrap if used: the patch was mounted on Micropore tape, which was wrapped around the abdomen and secured with Coban elastic bandage

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes, by using tap water
- Time after start of exposure: 4 hrs

SCORING SYSTEM: according to OECD 404

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

other: mean for animals #1, #2 and #3

Time point:

other: Mean value of score at 24, 48 and 72h after patch removal

Score:

1.3

Max. score:

4

Reversibility:

fully reversible within: 14 days

Remarks on result:

other: Individual mean scores: 1.7-1.0-1.3

Results 2

Irritation parameter:

edema score

Basis:

other: mean for animals #1, #2 and #3

Time point:

other: Mean value of score at 24, 48 and 72h after patch removal

Score:

0

Max. score:

4

Remarks on result:

other: Individual mean scores: 0-0-0

Results 3

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1.7

Max. score:

2

Reversibility:

fully reversible within: 14 days

Results 4

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

1

Reversibility:

fully reversible within: 7 days

Results 5

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1.3

Max. score:

2

Reversibility:

fully reversible within: 7 days

Results 6

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Results 7

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Results 8

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritant / corrosive response data:

See section "Any other information on results incl. tables"

Other effects:

No symptoms of systemic toxicity were observed in the animals during the test period and no mortality occurred.

Any other information on results incl. tables

	Animal #1 (sentinel)			Animal #2			Animal #3
Time after exposure	Erythema	Oedema	comments	Erythema	Oedema	comments	Erythema	Oedema	comments
1 hour	1	0	Sticky remnants of the test substance present	1	0	Sticky remnants of the test substance present	2	0	Sticky remnants of the test substance present
24 hours	2	0		1	0		2	0
48 hours	2	0		1	0		1	0
72 hours	1	0		1	0		1	0
7 days	1	0	Fissuring of the skin	0	0	Fissuring of the skin	0	0	Fissuring of the skin
14 days	0	0		0	0		0	0

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In an in vivo skin irritation study in rabbits, conducted in accordance with OECD 404 and GLP, 3 female rabbits were semi-occlusively exposed for 4 hours to 0.5 mL of the undiluted substance. Application resulted in very slight or well-defined erythema in the treated skin areas of the three rabbits. The skin irritation resolved within 7 days in two animals and within 14 days in the other animal. Fissuring of the treated skin site was observed for all animals only at 7 days after application. Based on the result of this study, the substance does not need to be classified for skin irritation/corrosion in accordance with the CLP Regulation.