2-(6-methoxybenzofuran-2-yl)-1,3-dimethyl-5-(methylsulphonyl)1H-benzimidazolium acetate

Skin irritation / corrosion

Administrative data

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:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1977

Report date:

1977

Materials and methods

Principles of method if other than guideline:

The patch test technique described in the "Appraisal of the Safety of Chemicals in Foods, Drugs and Cosmetics" (1959), the US Association of Food and Drug Officials (AFDO)

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Fluorescent Brightener 363

IUPAC Name:

Fluorescent Brightener 363

Test animals

Species:

rabbit

Strain:

Himalayan

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 1.5 to 2 kg.
- Housing: animals were housed individually in metal cages.
- Diet: rabbit food - NAFAG, Gossau SG -, ad libitum.
- Water: ad libitum.
- Acclimation period: animals were adapted to our laboratories for a minimum of 8 days.

ENVIRONMENTAL CONDITIONS
- Temperature: 22 ± 1 °C
- Relative humidity: 55 ± 5 %
- Photoperiod: 14 hours light cycle day.

Test system

Type of coverage:

occlusive

Preparation of test site:

other: abraded and intact

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

0.5 g

Duration of treatment / exposure:

24 hours

Observation period:

72 hours

Number of animals:

3 male and 3 female rabbits

Details on study design:

TEST SITE
- Area of exposure: two days before treatment the entire back and the flank of the rabbits were shaved with an electric clipper and immediately before treatment the shaven skin on the left side was slightly scarified. For treatment gauze patches of 2.5 x 2.5 cm with test material were applied to the prepared abraded and non abraded skin.
- Type of wrap if used: the patches were covered with an impermeable material and were fastened to the body of the rabbit with adhesive tape.

OBSERVATION TIME POINTS
The skin irritation was scored immediately and 48 hours after removal of the dressings (24 and 72 hours after initiation of treatment).

SCORING SYSTEM
The severity of skin irritation was rated as follows: a mean value of less than 2 indicated mild, from 2 to 6 moderate and above 6 severe skin irritation.
The primary irritation index is the mean value of the sum of the scores for erythema and edema from all 6 rabbits 24 and 72 hours after initiation of treatment. The maximum possible score is 8

Erythema and eschar formation
No erythema 0
Very slight erythema (barely perceptible) 1
Well defined erythema 2
Moderate to severe erythema 3
Severe erythema (beet redness) to slight eschar formation (injuries in depth) 4
Maximum possible erythema score 4

Edema formation
No edema 0
Very slight edema (barely perceptible) 1
Slight edema (edges of area well defined by definite raising) 2
Moderate edema (raised approximately 1 mm) 3
Severe edema (raised more than 1 mm and extending beyond area of exposure) 4
Maximum possible edema score 4

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal: 6/6

Remarks:

both intact and abraded skin

Time point:

24/48/72 h

Score:

< 2.3

Reversibility:

fully reversible within: 72 hrs in the case of abraded skin

Remarks on result:

no indication of irritation

Remarks:

in the case of intact skin

Results 2

Irritation parameter:

edema score

Basis:

animal: 6/6

Remarks:

both intact and abraded skin

Time point:

24/48/72 h

Score:

< 2.3

Reversibility:

fully reversible within: 72 hrs in the case of abraded skin

Remarks on result:

no indication of irritation

Remarks:

in the case of intact skin

Irritant / corrosive response data:

The primary skin irritation index in the experiment was established to be 0.1. The test material caused therefore a mild skin irritation to rabbits.

Any other information on results incl. tables

Skin irritation in individual rabbits

Animal	Reaction	Intact skin		Abraded skin
		24 hrs	72 hrs	24 hrs	72 hrs
Male 1	Erythema	0	0	0	0
Male 2	Erythema	0	0	0	0
Male 3	Erythema	0	0	2	0
Female 4	Erythema	0	0	0	0
Female 5	Erythema	0	0	1	0
Female 6	Erythema	0	0	0	0
Male 1	Oedema	0	0	1	0
Male 2	Oedema	0	0	0	0
Male 3	Oedema	0	0	0	0
Female 4	Oedema	0	0	0	0
Female 5	Oedema	0	0	0	0
Female 6	Oedema	0	0	0	0

Applicant's summary and conclusion

Interpretation of results:

other: not classified, according to the CLP Regulation (EC) No 1272/2008

Conclusions:

Mild skin irritant.

Executive summary:

The skin irritation of the test item was evaluated in a study conducted according to the patch-test technique described in the "Appraisal of the Safety of Chemicals in Foods, Drugs and Cosmetics" (1959) of the US Association of Food and Drug Officials (AFDO). Six rabbits (3 males/3 females) of the Russian breed, weighing 1.5 to 2 kgs, were shaved on the whole back and flanks two days before treatment with an electric clipper. The shaven skin on the left side was slightly scarified immediately before treatment. A gauze patch of 2.5 x 2.5 cm with the test substance was applied to the prepared skin. The patches were covered with an impermeable material and were fixed to the body with adhesive tape. The substance was applied to each side in quantities of 0.5 g. The gauze patches were removed 24 hours after the application. The reaction of the skin was appraised upon removal and 72 hours after it. The primary irritation index as the measure of the acute skin irritation provoked by the substance is defined as the average of all the ratings found after 24 and 72 hours on the intact and slightly scarified skin. No erythema or edema were seen with the exposed intact skin. Slight irritation was observed with abraded skin of 3 rabbits. The primary irritation index was 0.1.

Conclusion

Mean values from gradings at 24, 48 and 72 hours after patch removal were lower than 2.3 in all the tested animals, for both intact and abraded skin and for both erythema/eschar and oedema reactions; therefore, the test item does not meet the criteria to be classified as irritating, according to the CLP Regulation (EC) No 1272/2008.