5,6,7-TRIMETHYLOCTA-2,5-DIEN-4-ONE

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 04 November 2003 to 24 November 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(2E,5Z)-5,6,7-trimethylocta-2,5-dien-4-one

Cas Number:

357650-26-1

Molecular formula:

C11H18O

IUPAC Name:

(2E,5Z)-5,6,7-trimethylocta-2,5-dien-4-one

Constituent 2

Reference substance name:

(2E,5E)-5,6,7-trimethylocta-2,5-dien-4-one

Cas Number:

847144-75-6

Molecular formula:

C11H18O

IUPAC Name:

(2E,5E)-5,6,7-trimethylocta-2,5-dien-4-one

Test material form:

liquid

Specific details on test material used for the study:

Batch No. 9000530064
Aspect: Slightly yellow liquid
Purity: 96.7%
Expiry date: 12-Sept-2004

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Elevage Scientifique des Dombes F-01400 Chatillon sur Chalaronne / France
- Age at study initiation: 12-13 weeks (male) / 18 weeks (females)
- Weight at study initiation: 1997 g (male) / 2639 & 2493 g (females)
- Housing: Individually in stainless steel cages equipped with feed hoppers and drinking water bowls. Wood blocks (RCC Ltd, Füllinsdorf) and haysticks 4646 were provided for gnawing.
- Diet (e.g. ad libitum): Pelleted standard Provimi Kliba 3418 rabbit maintenance diet ad libitum
- Water (e.g. ad libitum): community tap water from Füllinsdorf, ad libitum
- Acclimation period: 7 days, under laboratory conditions after health examination. Only without any visual signs of illness were used for the study.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17-23°C
- Humidity (%): 30-70%
- Air changes (per hr): 10-15 per hours
- Photoperiod (hrs dark / hrs light): 12 hours light and 12 hours dark

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL
- Concentration (if solution): Test material was used undiluted

Duration of treatment / exposure:

4 hours

Observation period:

14 days (1 hour, 24 hours, 48 hours, 72 hours, 7 days, 10 days and 14 days)

Number of animals:

3 (one male, two females)

Details on study design:

TEST SITE
- Area of exposure: 4 cm x 4 cm
- % coverage: Not precised
- Type of wrap if used: The patch was covered with a semi-occlusive dressing. The dressing was wrapped around the abdomen and anchored with tape.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The skin flushed with lukewarm tap water
- Time after start of exposure: 4 hours

OBSERVATION TIME POINTS
1 hour, 24 hours, 48 hours, 72 hours, 7 days, 10 days and 14 days.

SCORING SYSTEM:
- Method of calculation:
The skin reaction was assessed according to the numerical scoring system listed in the EEC Commission Directive 92/69/EEC, July 31, 1992 at approximately 1, 24, 48 and 72 hours, 7 days, 10 days and 14 days after the removal of the dressing, gauze patch and test item.

EEC COMMISSION DIRECTIVE 92/69/EEC, JULY 31, 1992
Grading of Skin Reactions
ERYTHEMA AND ESCHAR FORMATION
No erythema ...................................................................................................................................... 0
Very slight erythema ......................................................................................................................... l
Well-defined erythema ...................................................................................................................... 2
Moderate to severe erythema ............................................................................................................ 3
Severe erythema (beet redness) or eschar formation (injuries in depth preventing erythema)
reading .............................................................................................................................................. 4
OEDEMA FORMATION
No oedema ........................................................................................................................................ 0
Very slight oedema (barely perceptible) ........................................................................................... 1
Slight oedema (edges of area well-defined by definite raising). ........................................................ 2
Moderate oedema ( edges raised approximately 1 mm) ..................................................................... 3
Severe oedema (raised more than 1 mm and extending beyond the area of exposure) ..................... 4

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2.33

Max. score:

4

Reversibility:

fully reversible within: 14 days

Remarks on result:

positive indication of irritation

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2.33

Max. score:

4

Reversibility:

fully reversible within: 10 days

Remarks on result:

positive indication of irritation

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 10 days

Results 4

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 5

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1.67

Max. score:

4

Reversibility:

fully reversible within: 7 days

Irritant / corrosive response data:

The mean score was calculated across 3 scoring times (24, 48 and 72 hours after patch removal) for each animal for erythema/eschar grades and for oedema grades, separately. The mean erythema/eschar score of the three animals was 2.33, 2.33 and 2.00, respectively and the mean oedema score was 2.00, 2.00 and 1.67, respectively.

Very slight to well-defined erythema was observed in all animals at the 1-hour reading. Well defined erythema was noted in all animals 24 and 48 hours after treatment. The severity of redness of the skin increased in two animals at the 72 hours examination. Very slight to well defined erythema was still evident in all animals at the 7 day reading and very slight erythema persisted in one animal up to 10 days after treatment.

Very slight to slight swelling (oedema) was observed in all animals at the 1-hour reading. Slight swelling was visible in all 24 and 48 hours after treatment and very slight to slight swelling was still apparent in all animals at the 72 hours examination.

Scaling was noted in all animals from 7-day reading up to 14 days after treatment, the end of the observation period for all animals.

Other effects:

No staining produced by the test item of the treated skin was observed
Neither alterations of the treated skin were observed nor were corrosive effects evident on the skin.
The body weights of all rabbits were considered to be within the normal range of variability

Any other information on results incl. tables

Table 1: Skin irritation scores - individual values

Animal Number	Sex	Evaluation Interval*	Erythema	Oedema	Scaling
1 2 3	M F F	1 hour	1 1 2	1 2 2	0 0 0
1 2 3	M F F	24 hours	2 2 2	2 2 2	0 0 0
1 2 3	M F F	48 hours	2 2 2	2 2 2	0 0 0
1 2 3	M F F	72 hours	3 3 2	2 2 1	0 0 0
1 2 3	M F F	7 days	2 1 1	0 0 0	x x x
1 2 3	M F F	10 days	1 0 0	0 0 0	x x x
1 2 3	M F F	14 days	0 0 0	0 0 0	x x x

* Examinations were performed at the specific times after removal of the dressing

x = Scaling present

Table 2: Skin irritation scores - Individual mean values after 24, 48 and 72 hours

Animal Number	Sex	Erythema	N	Oedema	N
1 2 3	M F F	2.33 2.33 2.33	3 3 3	2.00 2.00 1.67	3 3 3

N = number of available data points

Table 3: Skin irritation scores - assessment according to EEC Guidelines

Evaluated intervals	Erythema	Oedema
24 hours 48 hours 72 hours	Irritating	Irritating

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Conclusions:

Based upon the referred classification criteria (Commission Directive 2001/59/EC of August 06, 2001), GR-85-2517 is considered to be "irritating" to the rabbit skin

Executive summary:

The primary irritation potential of GR-85 -2517 was investigated according to OECD test guideline No. 404. The test item was applied by topical semi-occlusive application of 0.5 mL to the intact left flank of each of three young adult New Zealand White rabbits. The duration of treatment was four hours. The scoring of skin reactions was performed 1, 24 48 and 72 hours, as well as 7, 10 and 14 days after removal of the dressing.

The mean score was calculated across 3 scoring times (24, 48, 72 hours after patch removal) for each animal for erythema/eschar grades and for oedema grades, separately. The mean erythema/eschar score of the three animals was 2.33, 2.33 and 1.67, respectively and the mean oedema score was 2.00, 2.00 and 2.00, respectively.

The application of GR-85 -2517 to the skin resulted in moderate signs of irritation. These effects included erythema, oedema and scaling. The oedema completely disappeared 7 days after treatment, the erythema 14 days after treatment and the sclaling were still evident 14 days after treatment, the end of the observation period for all animals. The test item caused no staining of the treated skin. No corrosive effects were noted on the treated skin of any animal at any of the measuring intervals and no other clinical signs of the test item related effects were observed.

Based upon the referred classification criteria (Commision Directive 2001/59/EC of August 06, 2001), GR-85 -2517 is considered to be "irritating" to rabbit skin