2-Pyridinecarboxylic acid, 4-(acetylamino)-3,6-dichloro-, methyl ester

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28 December 2012 to 5 January 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted to GLP 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:

2013

Report date:

2013

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:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Appearance: Variable coloured powder
- Storage conditions of the test material: Ambient (18 to 36 °C)
- pH: The pH of the test material as a 10 % aqueous solution was 5.05

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 7 to 8 months
- Weight at study initiation: 2.61 to 2.72 kg
- Fasting period before study: No
- Housing: The rabbits were housed individually in rabbit cages (size: approximately 65 cm long x 65 cm deep x 45 cm high) with a noryl shallow cage body and facilities for pelleted feed and drinking water. The litter collection trays (noryl waste tray) were changed daily (except on Sundays). A noryl perforated raised shelf was provided to the animals for enrichment.
- Diet (e.g. ad libitum): Rabbit feed was provided ad libitum in a stainless steel feed hopper.
- Water (e.g. ad libitum): Deep bore-well water passed through activated charcoal filter and exposed to UV rays in a water filter-cum-purifier was provided to animals ad libitum in 750 mL bottles with sipper tubes. The water in the bottles was replenished once daily and the water bottles were changed once a week.
- Acclimation period: Five days under laboratory conditions.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 to 23 °C
- Humidity (%): 65 to 66 % (relative)
- Air changes (per hr): 12 to 15 air changes/hour
- Photoperiod (hrs dark / hrs light): 12 hours of light and 12 hours of dark

IN-LIFE DATES: From: 28 December 2012 To: 05 January 2013

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Remarks:

The test material was made into a paste with Milli-Q water

Controls:

other: The adjacent untreated skin of each animal served as the control site.

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g

VEHICLE
- Amount(s) applied (volume or weight with unit): The test material was made into a paste by moistening with 0.25 mL of Milli-Q water.

Duration of treatment / exposure:

4 hours

Observation period:

72 hours

Number of animals:

3 male animals

Details on study design:

TEST SITE
- Area of exposure: An approximately 6 cm² intact test site was selected on each animal on the left dorsolateral trunk surface. Approximately 24 hours before treatment, the fur (about 14 x 19 cm) was clipped with an electric clipper and care taken to avoid abrading the skin. After clipping and prior to application, the test site was checked for any abnormalities according to the “Primary Skin Irritation Scoring System”; all the test sites were found to be normal.
- Type of wrap if used: The test material paste was applied on 6 ply cotton gauze (2 x 3 cm). The entire trunk of each animal was then wrapped with non-irritating semi-occlusive adhesive tape to avoid dislocation of the patch. Each rabbit was restrained using an Elizabethan collar for 4 hours post application of the test patch.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Test patches were removed and the test sites were washed with de-ionised water to remove any residual test material.
- Time after start of exposure: Following the 4 hour exposure period.

SCORING SYSTEM:
The test sites were examined for signs of erythema and oedema within 60 minutes and at intervals of approximately 24, 48 and 72 hours after test patch removal according to the "Primary Skin Irritation Scoring System" developed by Draize, et al. (1944).

OBSERVATIONS
- Clinical Observations: The rabbits were observed for clinical signs of toxicity and mortality 4 times (at hourly intervals) on the day of test material application and once daily thereafter until the end of the observation period.
- Body Weights: Body weights were recorded at the start of acclimatisation, day 1 of treatment (just before test material application) and at termination of observation.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Remarks:

of 3 animals

Time point:

other: Mean score at 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Remarks on result:

other: The erythema score was 0 at every time point for each animal

Results 2

Irritation parameter:

edema score

Basis:

mean

Remarks:

of 3 animals

Time point:

other: Mean score at 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Remarks on result:

other: The oedema score was 0 at every time point for each animal

Irritant / corrosive response data:

There were no skin reactions observed in all three rabbits at 1, 24, 48 and 72 hours post removal of the 4-hour test patch.

Other effects:

There were no clinical signs of toxicity observed, and none of the animals died, during the course of the study.
The body weight of all three rabbits increased throughout the observation period. See Table 1.

Any other information on results incl. tables

Table 1: Body Weight

Rabbit Number	Body weight (kg)
	At start of acclimatisation	At treatment	At termination of observation
RB9678	2.53	2.61	2.70
RB9679	2.63	2.70	2.73
RB9680	2.65	2.72	2.76

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of this study, the test material caused no irritation to the skin of male New Zealand White rabbits and requires no classification in accordance with EU criteria.

Executive summary:

The potential of the test material to cause skin irritation/corrosion in male New Zealand White rabbits was assessed in accordance with the standardised guidelines OECD 404 and US EPA OPPTS 870.2500 under GLP conditions.

0.5 g of the test material was made into a paste with 0.25 mL of Milli-Q water and applied to the clipped, intact skin of 3 animals in a semi-occlusive fashion for 4 hours.

The degree of irritation was evaluated and scored according to the Draize (1944) scale at 1, 24, 48 and 72 hours following removal of the test patch.

There were no clinical signs of toxicity or mortality and all animals gained weight. Neither erythema nor oedema was noted during the observation period under the conditions of the study.

Under the conditions of this study, the test material caused no irritation to the skin of male New Zealand White rabbits and requires no classification in accordance with EU criteria.