1H-Imidazole-1-ethanol, 4,5-dihydro-, 2-nortall-oil alkyl derivs.

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Between 31 March 2000 and 14 April 2000.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

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:

1H-Imidazole-1-ethanol, 4,5-dihydro-, 2-nortall-oil alkyl derivs.

EC Number:

263-171-2

EC Name:

1H-Imidazole-1-ethanol, 4,5-dihydro-, 2-nortall-oil alkyl derivs.

Cas Number:

61791-39-7

Molecular formula:

Not applicable (a generic molecular formula cannot be provided for this specific UVCB substance).

IUPAC Name:

2-{2-[(8Z)-heptadec-8-en-1-yl]-4,5-dihydro-1H-imidazol-1-yl}ethan-1-ol; 2-{2-[(8Z)-heptadec-8-en-1-yl]-4,5-dihydro-1H-imidazol-1-yl}ethyl (9Z)-octadec-9-enoate

Details on test material:

Sponsor's identification: PR 9061
Date received: 03 March 2000
Description: light amber liquid
Storage conditions: room temperature in the dark

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

Three New Zealand White rabbits supplied by David Percival Ltd, Moston, Sandbach, Cheshire, UK were used. At the start of the study the animals
weighed 2.75 to 3.13 kg and were twelve to sixteen weeks old. After a minimum acclimatisation period of five days each animal was given a number
unique within the study which was written with a black indelible marker-pen on the inner surface of the ear and on the cage label.

The animals were individually housed in suspended metal cages. Free access to mains drinking water and food (STANRAB SQC Rabbit Diet, Special Diets Services Ltd, Witham, Essex, UK) was allowed throughout the study.

The temperature and relative humidity were set to achieve limits of 17 to 23°C and 30 to 70% respectively. Any occasional deviations from these targets were considered not to have affected the purpose or integrity of the study. The rate of air exchange was approximately fifteen changes per hour and the lighting was controlled by a time switch to give twelve hours continuous light and twelve hours darkness.

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit):
0.5 ml of the test material

- Concentration (if solution):
Not applicable.

Duration of treatment / exposure:

3 minutes, 1 hour and 4 hours

Observation period:

72 hours

Number of animals:

3

Details on study design:

On the day before the test each rabbit was clipped free of fur from the dorsal flank area using veterinary clippers. Only animals with a healthy intact
epidermis by gross observation were selected for the study.

One rabbit was initially treated. Three suitable test 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 (BLENDERM: approximate size 2.5 cm x 4.0 cm). To prevent the animal interfering with the patches, the trunk of the rabbit was wrapped in an elasticated corset (TUBIGRIP) 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. Any residual test material was removed by gentle swabbing with cotton wool soaked in 74% Industrial Methylated Spirits.

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 three minutes.

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 according to the scale of Draize J H, (1977) "Dermal and Eye Toxicity Tests" In: Principles and Procedures for Evaluating the Toxicity of Household Substances, National Academy of Sciences, Washington DC p.31. (Please see table in "further information on materials and methods" below)

An additional observation was made on Day 7 to assess the reversibility of skin reactions.

Interpretation of Results
Calculation of Primary Irritation Index and Grading of the Irritancy Potential Using the Draize Scheme
The scores for erythema and oedema at the 24 and 72-hour readings (4-hour exposure) were totalled for the three test rabbits (12 values) and th is
total was divided by six to give the primary irritation index of the test material. The test material was classified according to Draize J H (1959) "Dermal Toxicity" In: Appraisal of the Safety of Chemicals in Foods, Drugs and Cosmetics. Association of Food and Drug Officials of the United States, Austin, Texas, p.47:

Primary Irritation Index Classification of Irritancy
0 Non-irritant
> 0 to 2 Mild irritant
> 2 to 5 Moderate irritant
> 5 to 8 Severe irritant

If irreversible alteration of the dermal tissue is noted In any rabbit, as judged by the Study Director, which may include ulceration and clear
necrosis or signs of scar tissue, the test material is classified as corrosive to rabbit skin. Classification according to Draize may, therefore, not be
applicable.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

other: Erythema/Eschar Formation after 4 hours exposure.

Basis:

animal: 164 female

Time point:

other: Scoring only possible at 24 hour observation.

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks:

at seven days: Sunken, hardened, dark brown/black coloured scab resembling a crater; scab undulating; animal killed.

Remarks on result:

other: Adverse dermal reactions precluded evaluation of erythema.

Results 2

Irritation parameter:

other: Erythema/Eschar Formation after 1 hour exposure

Basis:

animal: 164 female

Time point:

other: Scoring only possible for 24 and 48 hour observation (scored the same on both evaluations).

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks:

at seven days: hardened dark brown/black scab, animal killed.

Remarks on result:

other: Adverse dermal reactions precluded evaluation of erythema.

Results 3

Irritation parameter:

other: Erythema/Eschar Formation after 3 minutes exposure.

Basis:

animal: 164 female

Time point:

other: mean of 24, 48 and 72 hour observations.

Score:

0

Max. score:

4

Reversibility:

not fully reversible within: seven days

Remarks on result:

other: slight desquamation noted on seven day observation.

Results 4

Irritation parameter:

other: Erythema/Eschar Formation after 3 minutes exposure.

Basis:

animal: 32 female

Time point:

other: mean of 24, 48 and 72 hour observations.

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Remarks on result:

other: Observation at seven days not performed.

Results 5

Irritation parameter:

other: Erythema/Eschar Formation after 3 minutes exposure.

Basis:

animal: 36 male

Time point:

other: mean of 24, 48 and 72 hour observations.

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 24 hours: effects noted at one hour observation.

Remarks on result:

other: Observation at seven days not performed.

Results 6

Irritation parameter:

other: Oedema Formation after 4 hours exposure.

Basis:

animal: 164 female

Time point:

other: Scoring only possible at 24 hour observation.

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: Adverse dermal reactions precluded evaluation of oedema.

Results 7

Irritation parameter:

other: Oedema Formation after 1 hour exposure.

Basis:

animal: 164 female

Time point:

other: Scoring only possible for 24 and 48 hour observation (scored the same on both evaluations).

Score:

2

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: Adverse dermal reactions precluded evaluation of oedema.

Results 8

Irritation parameter:

other: Oedema Formation after 3 minutes exposure.

Basis:

animal: 164 female

Time point:

other: mean of 24, 48 and 72 hour observations.

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 24 hours: effects noted at one hour observation.

Results 9

Irritation parameter:

other: Oedema Formation after 3 minutes exposure.

Basis:

animal: 32 female

Time point:

other: mean of 24, 48 and 72 hour observations

Score:

0

Max. score:

4

Reversibility:

other: No effects noted.

Remarks on result:

other: Observation at seven days not performed.

Results 10

Irritation parameter:

other: Oedema Foramtion after 3 minutes exposure.

Basis:

animal: 36 male

Time point:

other: mean of 24, 48 and 72 hour observations

Score:

0

Max. score:

4

Reversibility:

other: No effects noted.

Remarks on result:

other: Observation at seven days not performed.

Irritant / corrosive response data:

4- hour exposure
The individual scores for erythema/eschar and oedema are given in Table 1 in remarks on results including tables and figures.
Moderate to severe erythema and moderate oedema were noted at the treated skin site at the 1-hour observation with severe erythema and severe oedema at the 24-hour observation. Haemorrhage of the dermal capillaries was noted at the treated skin site at the 1 and 24-hour observations. Loss of skin elasticity and flexibility were noted at the treated skin site at the 24-hour observation. Hardened dark brown/black coloured scab was noted at the treated skin site at the 48 and 72-hour observation with sunken, hardened, dark brown/black coloured scab resembling a crater at the 7-day observation. The scab appeared undulating at the 72-hour and 7-day observations. Skin reactions prevented accurate evaluation of erythema and oedema
at the treated skin site at the 48, 72-hour and 7-day observations.

1 - hour exposure
The individual scores for erythema/eschar and oedema are given in Table 2 in remarks on results including tables and figures.
Moderate to severe erythema and slight oedema were noted at the treated skin site at the 1-hour observation with severe erythema and slight oedema at the 24 and 48-hour observations. Haemorrhage of the dermal capillaries was noted at the treated skin site at the 1, 24 and 48-hour observations. Loss of skin elasticity and flexibility were noted at the treated skin site at the 24 and 48-hour observations. Hardened dark brown/black coloured scab, preventing accurate evaluation of erythema and oedema was noted at the treated skin site at the 72-hour and 7-day observation.

3 minute exposure
The individual scores for erythema/eschar and oedema are given in Table 3 in remarks on results including tables and figures.
Very slight erythema and very slight oedema were noted at the treated skin site at the 1-hour observation. Slight desquamation was noted at the treated skin site at the 7-day observation.

Any other information on results incl. tables

Table 1

Individual Skin Reactions Following 4 -Hour Exposure Period.

Skin Reaction	Observation Time	Individual Scores – Rabbit Number and Sex (Bodyweight kg)
		164 Female (3.13)
Erythema/Eschar Formation	1 Hour	3Hd
	24 Hours	4HdLeLf
	48 Hours	?eSt
	72 Hours	?eStSw
	7 Days	?eSuSwK
Oedema Formation	1 Hour	3
	24 Hours	4
	48 Hours	?od
	72 Hours	?od
	7 Days	?od
Classification                                                      :                          CORROSIVE

Hd = dermal haemorrhage over the majority of the treatment site

Le = loss of skin elasticity

Lf = loss of skin flexibility

St = hardened dark brownlblack coloured scab

Su = sunken, hardened, dark brown/black coloured scab resembling a crater

Sw = scab undulating

?od = adverse dermal reactions precluded evaluation of oedema

?e = adverse dermal reactions precluded evaluation of erythema

K = animal killed. Reactions considered irreversible. Test material therefore classified as corrosive. Animal killed for humane reasons in accordance with company policy and Home Office guidelines.

Table 2

Individual Skin Reactions Following 1 -Hour Exposure Period.

Skin Reaction	Observation Time	Individual Scores – Rabbit Number and Sex (Bodyweight kg)
		164 Female (3.13)
Erythema/Eschar Formation	1 Hour	3Hd
	24 Hours	4HdLeLf
	48 Hours	4HdLeLf
	72 Hours	?eSt
	7 Days	?eSt K
Oedema Formation	1 Hour	2
	24 Hours	2
	48 Hours	2
	72 Hours	?od
	7 Days	?od

Hd = dermal haemorrhage scattered over the treatment site

Le = loss of skin elasticity

Lf = loss of skin flexibility

St = hardened dark brown/black colnured scab

?od - adverse dermal reactions precluded evaluation of oedema

?e = adverse dermal reactions precluded evaluation of erythema

K= animal killed. Reactions considered irreversible. Test material therefore classified as corrosive. Animal killed for humane reasons in accordance with company policy and Home Office guidelines.

Table 3

Individual Skin Reactions Following 3 -Minutes Exposure Period.

Skin Reaction	Observation Time	Individual Scores – Rabbit Number and Sex (Bodyweight kg)
		164 Female (3.13)	32 Female (2.76)	36 Male (2.75)
Erythema/Eschar Formation	1 Hour	1	1	1
	24 Hours	0	1	0
	48 Hours	0	0	0
	72 Hours	0	0	0
	7 Days	0D	-	-
Oedema Formation	1 Hour	1	0	0
	24 Hours	0	0	0
	48 Hours	0	0	0
	72 Hours	0	0	0
	7 Days	0	-	-

D = slight desquamation

- no data, observation not performed

Applicant's summary and conclusion

Interpretation of results:

Category 1B (corrosive) based on GHS criteria

Conclusions:

The test material was classified as a CORROSIVE to rabbit skin (based on one rabbit only).

Executive summary:

A study was performed to assess the irritancy potential of the test material to the skin of the New Zealand White rabbit. The method used followed the recommendations of the OECD Guidelines for Testing of Chemicals No. 404 "Acute Dermal Irritation/Corrosion" (adopted 17 July 1992) and Method B4 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC).

The results may be used as a basis for classification and labelling under Annex VI of Council Directive 67/548/EEC (as adapted to technical progress by Commission Directive 93/21/EEC) relating to the classification, packaging and labelling of dangerous substances.

A single 4-hour, semi-occluded application of the test material to the intact skin of one rabbit produced reactions indicative of dermal corrosion. The reactions included severe erythema, severe oedema and scabbing.

3-minute and 1-hour semi-occluded applications of the test material to the intact skin of one rabbit produced no corrosive effects.

The test material was classified as a corrosive to rabbit skin (based on one rabbit only).

The test material was also classified as corrosive according to EU labelling regulations. The symbol "C" and risk phrase R 34 "CAUSES BURNS" are required.