3,5-xylidine

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 JAN 1990 - 09 JAN 1990

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Reference 2

Reference Type:

secondary source

Title:

Xylidine, BUA Stoffbericht 161

Year:

1994

Bibliographic source:

BUA, Beratergremium für umweltrelevante Altstoffe (BUA) der Gesellschaft Deutscher Chemiker, S.Hirzel Verlag 1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Principles of method if other than guideline:

Slight modifications from the guidelines (e.g: more accurate description and scoring of corneal defects, additional examination of aqueous humour) this does not affect the validity of the study.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

3,5-xylidine

EC Number:

203-607-0

EC Name:

3,5-xylidine

Cas Number:

108-69-0

Molecular formula:

C8H11N

IUPAC Name:

3,5-dimethylaniline

Test material form:

liquid

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Interfauna U.K. Ltd. Wyton, Huntingdon, England
- Age at study initiation: adult
- Weight at study initiation: 3.1 - 3.2 kg
- Housing: the rabbits were individually housed in stainless steel cages with flat rod bases or polyethylene cages with perforated bases, under standardized conventional conditions. Excrement trays beneath the cages contained low dust (wood) bedding (type S 8/15, Ssniff spezialdiaten GmbH, Soest). Bedding was regularly spot checked for contaminants at the instance of the Department of Laboratory Animal Services and changed at least twice weekly.
All the animals in this study were kept in one room. For capacity reasons, rabbits treated with other test substances were also housed in the same room. Adequate separation, clear cage and individual marks, as well as appropriate organization of working procedures ensured that the test animals were not mixed up.
- Diet (e.g. ad libitum): Standard diet Ssniff K 4, approx. 100 - 120g per animal/day; once per day in the morning. The nutritive composition and contaminant content of the standard diet were routinely spot checked and analysed at the instance of the department of laboratory animal services.
- Water (e.g. ad libitum): Tap water; ad libitum. The tap water was of drink water quality (Drink water ordinance of May 22, 1986, Federal Law Gazette (Bundesgesetzblatt) part I, page 760). The drink water was regularly examined at the instance of the Quality Assurance, Bayer AG. The results of the feed and water analyses provided no evidence of interference with the study objective. Drink water was supplied either in polycarbonate bottle containing approx. 750mL or from automatic watering.
- Acclimation period: Prior to the initiation of the treatment the animals were kept for at least 14 days in the quarantine station of the Dpartment of the Laboratory Animal Services and monitored for diseases. During this period pooled faeces specimens were examined for Coccidia oocysts.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 ± 3 °C
- Humidity (%): approx 50 %
- Air changes (per hr): approx 10 times per hour
- Photoperiod (hrs dark / hrs light): 12 hours, artificial illumination from 6 to 18hrs CET
The humidity and air temperature were continuously recorded using a calibrated thermohygrograph (type 252, Lambrecht Co. Gottingen). Occasional excursions from these conditions, e.g., due to cleaning of the room, had no detectable influence on the outcome of the study.

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent negative control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 500 μg of the test substance was applied to a hypoallergenic Hansmed patch (Beiersdorf no. 2342 PV3).

NEGATIVE CONTROL: A further patch was moistened with water

Duration of treatment / exposure:

4 h

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: dorsolateral area of the trunk (6 x 6 cm) of each of three rabbits.
- Type of wrap if used: Each animal was loosely held in place with a semi occlusive dressing (Fixomull - stretch klebevlies, Beiersdorf no. 2293) for the duration of the exposure period. Thus, access by the animal to the patch and resultant ingestion/ inhalation of the test substance was prevented.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The exposed skin areas were carefully washed with water without altering the existing response, or the integrity of the epidermis
- Time after start of exposure: 4 hours

OBSERVATION TIME POINTS: 1h, 24h, 48h, 72h and 7 days

SCORING SYSTEM:
- Method of calculation: DRAIZE

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal:

Time point:

other: 1 h

Score:

0

Remarks on result:

no indication of irritation

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 1 h

Score:

0

Remarks on result:

no indication of irritation

Results 3

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Remarks on result:

no indication of irritation

Results 4

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Remarks on result:

no indication of irritation

Results 5

Irritation parameter:

erythema score

Basis:

mean

Time point:

7 d

Score:

0

Remarks on result:

no indication of irritation

Results 6

Irritation parameter:

edema score

Basis:

mean

Time point:

7 d

Score:

0

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

The substance was found to be not irritating on semi occlusive application on the skin of white rabbits for 4 h.

Any other information on results incl. tables

Evaluation of results

For each animal the DRAIZE scores recorded approx. 24, 48 and 72 hours after application were added. The total of these three values was divided by three to give the irritation index. This index was separately calculated for erythema/eschar formation and for edema formation. Where three animals were used, interpretation was based on the individual indices obtained from the two most sensitive animals. Where more than three animals were used, the mean irritation index was calculated by averaging the total scores of all rabbits tested. If delayed reactions occurred, or where no irritation indices could be calculated (e.g. due to coloration by the test substance) other interpretation criteria were applied.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

EU GHS criteria not met

Conclusions:

All three animals did not show any signs of irritation such as erythema or edema on the skin of white rabbits.

Executive summary:

Skin irritation test was done according to OECD Guideline 404 under GLP compliance. 3 of New Zealand white rabbits were exposed to the test item for 4 hours semi occlusive. Observation was done 1, 24, 48, 72hr and 7days after the exposure. All three animals did not show any signs of irritation such as erythema or edema on the skin.