2-methyl-3-butenenitrile

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Not stated

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Draize method but the purity is not indicated. Comparable to guideline, with acceptable restrictions (24-h exposure, observations at 25 and 48 h only, occlusive dressing).

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1981

Report date:

1981

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

: 24 hours of application, only two time points instead of three, and occlusive coverage instead of semi-occlusive. No details on test material, condition and animals.

Principles of method if other than guideline:

Draize test: Local tolerance test in rabbit, evaluation of the index of primary cutaneous irritation on intact skin.

GLP compliance:

not specified

Remarks:

study performed before GLP statement.

Test material

Test material information

Constituent 1

Reference substance name:

2-methyl-3-butenenitrile

EC Number:

240-596-1

EC Name:

2-methyl-3-butenenitrile

Cas Number:

16529-56-9

Molecular formula:

C5H7N

IUPAC Name:

2-methylbut-3-enenitrile

Details on test material:

- Name of test material (as cited in study report): 2-methyl-3-butenenitrile
- Substance type: no data
- Physical state: light yellow liquid
- Impurities (identity and concentrations): no data
- Composition of test material, percentage of components: no data
- Purity test date: no data
- Expiration date of the lot/batch: no data
- Stability under test conditions: no data
- Storage condition of test material: no data
- Other: no data

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: no data
- Age at study initiation: no data
- Weight at study initiation: From 2.5 kg to 3.5 kg
- Housing: no data
- Diet (e.g. ad libitum): no data
- Water (e.g. ad libitum): no data
- Acclimation period: no data


ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data


IN-LIFE DATES: no data

Test system

Type of coverage:

occlusive

Preparation of test site:

other: abraded or scarified

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5g (or 0.5 mL)
- Concentration (if solution): no data


VEHICLE
no vehicle

Duration of treatment / exposure:

24 hours

Observation period:

25 and 72 hours

Number of animals:

4

Details on study design:

TEST SITE
- Area of exposure: circle of 3 cm of diameter
- % coverage: no data
- Type of wrap if used: aluminium with gaze maintain with adhesive tape and enveloping bandage


REMOVAL OF TEST SUBSTANCE
- Washing (if done): no
- Time after start of exposure: 24 hours


SCORING SYSTEM: Draize scoring.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Remarks:

intact skin

Time point:

other: Overall 25 and 72 hrs

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Remarks on result:

other: See details in Tables 7.3.1/1 and 7.3.1/2

Results 2

Irritation parameter:

edema score

Basis:

mean

Remarks:

intact skin

Time point:

other: Overall 25 and 72 hrs

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Remarks on result:

other: See details in Tables 7.3.1/1 and 7.3.1/2

Results 3

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: Overall 25 and 72 hrs

Score:

0.06

Max. score:

12

Reversibility:

fully reversible within: 72 hrs

Remarks on result:

other: this index is equal to the sum of the scores for erythema and edema at 25 and 72 hrs after the application for the both intact and abraded skin, divided by 16 (number of treated rabbits multiplied by 4).

Irritant / corrosive response data:

On the treated intact skin, no effect was observed: mean score was 0.0 for erythema and edema. On the treated abraded skin, a very slight and transient erythmea was observed for one animal. No edema was seen on the abraded skin of the other animals. See details in Tables 7.3.1/1 and 7.3.1/2

Other effects:

No data

Any other information on results incl. tables

Table 7.3.1/1:Mean irritant/corrosive response data for each animal with intact skin at each observation time up to removal of animals from the test

 

Score at time point / Reversibility	Erythema Max. score 4	Edema Max. score 4
25 h after the start of test item application	0/0/0/0	0/0/0/0
72 h after the start of test item application	0/0/0/0	0/0/0/0
Average 25h, 72h (mean of all animals)	0.0	0.0
Reversibility*)	c/c/c/c	c/c/c/c
Average time (hrs) for reversion	-	-

 

 

Table 7.3.1/2: Mean irritant/corrosive response data for animals with abraded skin at each observation time up to removal of animals from the test

 

Score at time point / Reversibility	Erythema Max. score 4	Edema Max. score 4
25 h after the start of test item application	0/0/1/0	0/0/0/0
72 h after the start of test item application	0/0/0/0	0/0/0/0
Average 25h, 72h	0.125	0.0
Reversibility*)	-/-/c/-	-/-/-/-
Average time (hrs) for reversion	-/-/72/-	-

*) Reversibility: c. = completely reversible; n.c. = not completely reversible; n. = not reversible

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under these test conditions, no irritant response was detected, 2-methyl-3-butenenitrile was not classified as a skin irritating according to EU criteria.

Executive summary:

In a dermal irritation study performed similarly to the OECD test guideline No. 404, 4 New Zealand White rabbits were exposed to 0.5 mL of undiluted 2 -methyl-3 -butenenitrile. Skin was shaved before application; on each animal one area was intact whereas the other was abraded. Test sites were covered with an occlusive dressing for 24 hours and weren’t washed after this period. Changes were observed at 25 and 72 hours. Irritation was scored by the method of Draize. On the treated intact skin, no effect was observed. Mean score was 0.0 for erythema and edema.

Under the condition of this test, 2 -methyl-3 -butenenitrile is not a skin irritant. Thus no classification is required according to EU legislation (Regulation 1278/2008/EC and Directive 67/548/EEC).