2-Pyridinecarboxylic acid, 4-amino-3,6-dichloro-

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 June 2001 to 30 August 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

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

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: JMAFF Primary Dermal Irritation Study, 2000

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

4-amino-3,6-dichloropyridine-2-carboxylic acid

EC Number:

604-721-7

Cas Number:

150114-71-9

Molecular formula:

C6H4Cl2N2O2

IUPAC Name:

4-amino-3,6-dichloropyridine-2-carboxylic acid

Test material form:

solid: particulate/powder

Details on test material:

- Appearance: tan powder

Specific details on test material used for the study:

Purity: 94.5%

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 17 - 18 weeks
- Weight at study initiation: 2.50 - 2.57 kg
- Housing: animals were individually housed in stainless steel cages
- Diet: 5 ounces of diet per day
- Water: ad libitum
- Acclimation period: at least 2 weeks

ENVIRONMENTAL CONDITIONS
- Temperature: 19 ± 3 °C
- Humidity: 40 - 60 % (relative)
- Air changes: 12 - 15 air changes per hour
- Photoperiod: 12 hours of darkness / 12 hours of light (06:00 to 18:00)

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Remarks:

the test material was moistened with 0.3 mL of 0.5 % aqueous methylcellulose

Controls:

no

Amount / concentration applied:

The day prior to study start, an area approximately 10 x 10 cm of the back of three New Zealand White rabbits was clipped free of fur. On day 1, a 0.5 g aliquot of the test material moistened with 0.3 mL of 0.5 % aqueous methylcellulose was applied to the back of each rabbit.

Duration of treatment / exposure:

4 hours

Observation period:

72 hours after test material removal.

Number of animals:

Three, one male and two females.

Details on study design:

TEST SITE
The test material was applied to the back of each rabbit and covered with a gauze patch (semi-occlusive dressing ~6 x 6 cm) with cotton backing. The gauze patch was held in place with an elastic jacket.

REMOVAL OF TEST SUBSTANCE
The jacket and patch were removed after four hours, and the back was wiped with a damp disposable towel to remove any residual test material.

SCORING SYSTEM
The application sites were graded for erythema and oedema within thirty minutes, and 24, 48, and 72 hours after test material removal. The grades for dermal lesions were assigned according to the Draize scoring system as follows:

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

> Oedema formation
0 = No oedema
1 = Very slight oedema (barely perceptible)
2 = Slight oedema (edges of area well-defined by definite raising)
3 = Moderate oedema (edges raised approximately 1 mm)
4 = Severe oedema (raised more than 1 mm and extending beyond the area of exposure)

OTHER EXAMINATIONS
Animals were weighed on the day of treatment and at study termination.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Results 2

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Results 3

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Results 4

Irritation parameter:

edema score

Basis:

animal #2

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Results 5

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritant / corrosive response data:

There were no signs of dermal irritation in any of the three rabbits during the study. The rabbits were removed from study 72 hours after unwrapping.

Other effects:

All rabbits gained body weight over the 72-hour period.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

There were no signs of dermal irritation in any of the three rabbits during the study.

Executive summary:

The skin irritation potential of the test material was investigated in a study which was conducted under GLP conditions and in accordance with the standardised guidelines OECD 404, EU Method B.4, EPA OPPTS 870.2500 and JMAFF (2000).

During the study aliquots of 0.5 g test material (moistened with 0.3 mL of 0.5 % aqueous methylcellulose) were applied to 1 male and 2 female New Zealand White rabbits for approximately 4 hours to the intact skin on the back of each rabbit. There were no signs of dermal irritation in any of the three rabbits during the study. The rabbits were removed from study 72 hours after unwrapping. All rabbits gained body weight over the 72-hour period.