1-[[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 Sep 2010 to 20 Oct 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

April 24, 2002

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Version / remarks:

August 1998

Test guideline 3

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

May 30, 2008

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

1-[[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole

EC Number:

262-104-4

EC Name:

1-[[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole

Cas Number:

60207-90-1

Molecular formula:

C15H17Cl2N3O2

IUPAC Name:

1-{[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl}-1H-1,2,4-triazole

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Number of animals per test: 3 (males)
- Age at treatment: ~17 weeks
- Acclimatization: Under laboratory conditions after health examination. Only animals without any visual signs of illness were used for the study.
- Housing: Rabbits were individually housed in AAALC approved metal wire rabbit cages (65x65 cm with height of 45 cm). Cages are of an open wire structure and cages are placed together to allow some social interaction with rabbit(s) in adjoining cages.
- Diet: ad libitum.
- Water: The animals received municipal tap water, as for human consumption, ad libitum, from an automatic system. The drinking water is routinely analysed and is considered not to contain any contaminants that could reasonably be expected to affect the purpose or integrity of the study.

ENVIRONMENTAL CONDITIONS
- Temperature: 17.1-21.4°C
- Relative humidity: 40 -87%
- Ventilation: 15-20 air exchanges/hour.
- Lighting periods: 12 hours daily, from 6.00 a.m. to 6.00 p.m.

IN-LIFE DATES: 29 Sep 2010 to 20 Oct 2010

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 g per animal

Duration of treatment / exposure:

4 hours

Observation period:

3 weeks

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: 2.5 cm x 2.5 cm back and the flanks of the animal
- Type of wrap if used: Adhesive hypoallergenic plaster; the entire trunk of the animals was wrapped with plastic wrap held in place with an elastic stocking

REMOVAL OF TEST SUBSTANCE
- Washing: The dressing was removed and the skin was flushed with lukewarm tap water to clean the application site
- Time after start of exposure: 4 hours

OBSERVATION TIME POINTS
- 1, 24, 48, 72 hours, 1, 2 and 3 weeks after the end of exposure.

SCORING SYSTEM:
- Scoring system: The skin reaction was assessed according to the numerical scoring system listed in the Commission Directive 2004/73/EC, April 29, 2004 which was based on the Draize scoring system.
- Method of calculation: 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. An animal was positive when the mean score was 2 or greater. The test was positive for irritation when at least 2 animals were positive for the same endpoint (erythema/eschar or oedema).

OBSERVATIONS:
- Viability/mortality, clinical signs and dermal findings were recorded.
- Body weights were recorded at the beginning and at the end of experiment.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal: #1, #2 and #3

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 3 weeks

Results 2

Irritation parameter:

edema score

Basis:

animal: #1 and #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Results 3

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.66

Max. score:

4

Reversibility:

fully reversible within: 1 week

Results 4

Irritation parameter:

overall irritation score

Basis:

animal: #1, #2 and #3

Time point:

24/48/72 h

Score:

1.22

Max. score:

8

Remarks on result:

probability of mild irritation

Irritant / corrosive response data:

At observations 1 hour after patch removal, very slight oedema (score 1) was observed in 2 animals. Oedema persisted in 1 animal and was observed at the 24- and 48 hour observations. Very slight erythema (score 1) was recorded in all animals from 1 hour after patch removal and at all subsequent observations up to and including the 1 week observations. At the 2 week observations very slight erythema (score 1) was still observed in 2 animals. Dry cracked skin surface was observed in all animals at the 1 week observation and in 1 animal at the 2 week observation.
As signs of irritation were observed after 2 weeks, irreversibility could not be determined and the study was therefore extended by 1 week. All animals fully recovered and showed no local signs at the 3 weeks observation.

Any other information on results incl. tables

Table 1. Skin Irritation Scores - Individual Values

Sex	Evaluation Interval*	Erythema	Oedema	Cumulative
				Score	Mean
male		1	1	2.00
male	1 hour	1	0	1.00	1.67
male		1	1	2.00
male		1	0	1.00
male	24 hours	1	0	1.00	1.33
male		1	1	2.00
male		1	0	1.00
male	48 hours	1	0	1.00	1.33
male		1	1	2.00
male		1	0	1.00
male	72 hours	1	0	1.00	1.00
male		1	0	1.00
male		1	0	1.00
male	1 week	1	0	1.00	1.00
male		1	0	1.00
male		1	0	1.00
male	2 weeks	1	0	1.00	0.67
male		0	0	0.00
male		0	0	0.00
male	3 weeks	0	0	0.00	0.00
male		0	0	0.00

* Examinations were performed at the specified times after removal of the dressing.

Table 2. Skin Irritaion Scores – Mean Values After 24, 48 and 72 hours

Animal number	Sex	Erythema	N	Oedema	N	Primary Skin Irritaion Index
1	male	1	N	0	3	1.22
2	male	1	N	0	3
3	male	1	N	0.66	3
Mean score		1		0.22

N – number of available datapoints

Clinical observations

No clinical signs of systemic toxicity were observed in the animals during the study.
The body weights of all rabbits were considered to be within the normal range of variability.
No intercurrent deaths occurred throughout the study.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

According to the Draize classification criteria the test substance is considered to be a “mild- irritant” to rabbit skin (P.I.I. = 1.22) in the primary skin irritation potential test performed in compliance with GLP and according to the OECD 404 guideline.

Executive summary:

The primary skin irritation potential of test substance was investigated in compliance with GLP and according to the OECD 404 guideline. The animals were treated by topical semi-occlusive application of 0.5 g to the intact shaved flank of 3 young adult New Zealand White rabbits. The duration of treatment was 4 hours. The scoring of skin reactions was performed 1, 24, 48, 72 hours, 1, 2 and 3 weeks after removal of the dressing. The primary irritation index was calculated by totalling the mean cumulative scores at 24, 48 and 72 hours and then dividing by the number of data points.

The primary irritation index was 1.22. At observations 1 hour after patch removal, very slight oedema (score 1) was observed in 2 animals. Oedema persisted in 1 animal and was observed at the 24- and 48 hour observations. Very slight erythema (score 1) was recorded in all animals from 1 hour after patch removal and at all subsequent observations up to and including the 1 week observations. At the 2 week observations very slight erythema (score 1) was still observed in 2 animals. Dry cracked skin surface was observed in all animals at the 1 week observation and in 1 animal at the 2 week observation. As signs of irritation were observed after 2 weeks, irreversibility could not be determined, and the study was therefore extended by 1 week. All animals fully recovered and showed no local signs at the 3 weeks observation.

The study was terminated after the 3 weeks observation as no signs were observed in the treated animals.

According to the Draize classification criteria the test substance is considered to be a “mild- irritant” to rabbit skin (P.I.I. = 1.22) in the primary skin irritation potential test performed in compliance with GLP and according to the OECD 404 guideline.