2-hydroxy-4-(methylthio)butyronitrile

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From: 1 September 1998 To: 25 September 1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Test material

Test material information

Constituent 1

Reference substance name:

2-hydroxy-4-(methylthio)butyronitrile

EC Number:

241-756-3

EC Name:

2-hydroxy-4-(methylthio)butyronitrile

Cas Number:

17773-41-0

Molecular formula:

C5H9NOS

IUPAC Name:

2-hydroxy-4-(methylsulfanyl)butanenitrile

Details on test material:

- Name of test material (as cited in study report): 2-hydroxy-4-méthylthiobutyronitrile
- Physical state: pale yellow liquid
- Analytical purity: 75.77% (TOS) / 74.5 % (HPLC)
- Purity test date: no data
- Lot/batch No.: MO69
- Expiration date of the lot/batch: no data
- Storage condition of test material: at room temperature

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River France, 76410 Saint-Aubin-lès-Elbeuf, France.
- Age at study initiation: approximately 3 months old
- Weight at study initiation: the animals had a mean body weight of 353 +/- 12 g for males and 349 +/- 11 g for females.
- Housing: individually in polycarbonate cages
- Diet : ad libitum, 106 pelleted diet (UAR, 91360 Villemoisson-sur-Orge, France)
- Water : ad libitum, water filtered by a FG Millipore membrane (0.22 micron)
- Acclimation period: at least 5 days before the beginning of the study


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 +/- 2
- Humidity (%): 30 to 70
- Air changes (per hr): 12
- Photoperiod : 12 hrs dark / 12 hrs light


IN-LIFE DATES: From: 1 September 1998 To: 25 September 1998

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

corn oil

Induction 2

Concentration / amount:

intradermal induction: 1 %
cutaneous induction: application of 0.5 ml of undiluted test substance
cutaneous challenge: application of 0.5 ml of undiluted test substance

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

corn oil

Challenge 2

Concentration / amount:

intradermal induction: 1 %
cutaneous induction: application of 0.5 ml of undiluted test substance
cutaneous challenge: application of 0.5 ml of undiluted test substance

No. of animals per dose:

Control group: 5 males and 5 females
Treated group: 10 males and 10 females

Details on study design:

RANGE FINDING TESTS:
Intradermal test: 50, 25, 10, 5, 1 and 0.1 %
Cutaneous test: 100 and 50 %

MAIN STUDY
A. INDUCTION EXPOSURE
* Intradermal induction:
- On day 1, 3 injections are realized into each side of the enterscapular area:
- 0.1 mL of Freund's complete adjuvant at 50 % in 0.9% NaCl
- 0.1mL of the test item at 1 % (for treated group) or 0.1mL of vehicle (for control group)
- 0.1mL of a mixture 50/50 (V/V) of Freund's complete adjuvant in 0.9% NaCl and the test item at 1 % (for treated group) or the vehicle (for control group).

* Cutaneous induction:
- On day 7, local irritation is induced by application of Sodium Laurylsulfate 10 % in Vaseline
- On day 8, occlusive application on the scapular area of 0.5 mL of the undiluted test item (for treated group) or vehicle (for control group) for 48hours

B. CHALLENGE EXPOSURE D22
On day 22, 24hours occlusive application on the scapular area of 0.5mL of the undiluted test item on the right flank and 0.5mL of the vehicle on the left flank.
Reactions are evaluated 24 and 48 hours after removal of the dressing

Challenge controls:

No

Positive control substance(s):

yes

Remarks:

2,4-Dinitro Chlorobenzene (DNCB)

Results and discussion

Positive control results:

The sensitivity of the guinea-pigs in CIT experimental conditions was checked with a positive sensitizer, 2,4-Dinitro Chlorobenzene (DNCB) in a recent study (CIT/Study No. 17335 TSG- September 1998). During the induction period the reference substance DNCB was applied at the concentration of 0.1% (w/w) (day 1) and 1% (w/w) (day 8) in corn oil. For the challenge application, DNCB was applied at the concentration of 1% (w/w) in corn oil.
The species and strain used for positive control showed satisfactory sensitization response in 90 % animals treated with DNCB

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

0.5 ml of the vehicule

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 0.5 ml of the vehicule. No with. + reactions: 0.0. Total no. in groups: 10.0.

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

0.5 ml of the vehicule

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 0.5 ml of the vehicule. No with. + reactions: 0.0. Total no. in groups: 10.0.

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

0.5 ml of the undiluted test substance

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 0.5 ml of the undiluted test substance. No with. + reactions: 0.0. Total no. in groups: 20.0.

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

0.5 ml of the undiluted test substance

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 0.5 ml of the undiluted test substance. No with. + reactions: 0.0. Total no. in groups: 20.0.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

Under these experimental conditions and according to the Magnusson and Kligman method, the test item, 2,4-Dinitro Chlorobenzene (undiluted), induced positive skin sensitization reactions in 0 /20 guinea pigs and is considered as not sensitizing.

Executive summary:

The delayed contact hypersensivity of 2,4-Dinitro Chlorobenzene was evaluated in Guinea pigs according to OECD N°406 guideline (Magnusson and Kligman test). The induction phase has been realized both by intradermal route on day 1 (1 % in vehicle) and by cutaneous route on day 8 (%) in 2 groups of guinea pigs: 5 males and 5 females for control group and 10 males and 10 females for treated group. The challenge phase was realized on day 22 by cutaneous application of undiluted test substance on the right flank (vehicle on the left flank); the cutaneous reactions were scored 24 and 48 hours after the challenge phase. One animal of the treated group was found dead on day 9. No clinical signs was observed prior to death. Macroscopic examination of the main organs of the animal found dead during the study revealed no apparent abnormalities. As mortality occurred after intradermal injections of the test substance in the preliminary test, this death could be attributed to the toxicity of the test substance. The body weight gain of the treated animals was normal when compared to that of the control animals. In conclusion, the test item was considered as not sensitizing in guinea pigs.