N-tert-butylbenzothiazole-2-sulphenamide

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1983

Report date:

1983

Materials and methods

Principles of method if other than guideline:

Repeated Insult Patch test (modified Shelanski (4 x 4 method))

GLP compliance:

not specified

Type of study:

patch test

Justification for non-LLNA method:

The study was reported 1983. At this time an OECD guideline for a LLNA was not available.

Test material

Test material information

Constituent 1

Reference substance name:

N-tert-butylbenzothiazole-2-sulphenamide

EC Number:

202-409-1

EC Name:

N-tert-butylbenzothiazole-2-sulphenamide

Cas Number:

95-31-8

Molecular formula:

C11H14N2S2

IUPAC Name:

N-(1,3-benzothiazol-2-ylsulfanyl)-2-methylpropan-2-amine

Details on test material:

purity: 97.4 %

In vivo test system

Test animals

Species:

human

Sex:

male/female

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, semiocclusive

Vehicle:

petrolatum

Concentration / amount:

200 mg of the test material tested as a 60 % preparation in petrolatum

Challenge

Route:

epicutaneous, semiocclusive

Vehicle:

petrolatum

Concentration / amount:

200 mg of the test material tested as a 60 % preparation in petrolatum

No. of animals per dose:

54 volunteers

Details on study design:

The potential for TBBS to cause primary skin irritation and/or sensitization was assessed in 54 volunteer human subjects. This chemical was tested as a 60 % preparation in petrolatum.

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

200 mg

No. with + reactions:

15

Total no. in group:

54

Clinical observations:

mild to intense inflammatory changes

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 200 mg. No with. + reactions: 15.0. Total no. in groups: 54.0. Clinical observations: mild to intense inflammatory changes.

Results 2

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

200 mg

No. with + reactions:

13

Total no. in group:

54

Clinical observations:

mild to intense inflammatory changes

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 200 mg. No with. + reactions: 13.0. Total no. in groups: 54.0. Clinical observations: mild to intense inflammatory changes.

Results 3

Key result

Group:

negative control

Remarks on result:

other: Human patch test - no negative control group was included

Results 4

Key result

Group:

positive control

Remarks on result:

other: Human patch test - no positive control group was included

Any other information on results incl. tables

Forty-five subjects completed the study. During the induction period, eleven subjects demonstrated intense irritation consisting of erythema and induration. These responses were considered indicative of an allergic reaction. Due to the severity of reaction during the induction period, these eleven subjects were not tested during the portion of the induction phase which followed their response. Following the single 24 hour challenge application, six subjects demonstrated slight to moderate erythema. Twenty-four hours after removal of the test material, mild to intense inflammatory changes were observed in 15 individuals. At 48 hours after removal, responses were still noted in 13 subjects. These responses were considered characteristic for allergic contact dermatitis.

In conclusion, the test substance, tested as a 60 % preparation in petrolatum, produced sensitization in 13/54 subjects who completed the study. No evidence of primary irritation was observed.This chemical was considered to be a strong skin sensitizer.

Applicant's summary and conclusion

Interpretation of results:

Category 1A (indication of significant skin sensitising potential) based on GHS criteria

Conclusions:

The test substance, tested as a 60 % preparation in petrolatum, produced sensitization in 13/54 subjects who completed the study. No evidence of primary irritation was observed.This chemical was considered to be a strong skin sensitizer.

Executive summary:

Forty-five subjects completed the study. During the induction period, eleven subjects demonstrated intense irritation consisting of erythema and induration. These responses were considered indicative of an allergic reaction. Due to the severity of reaction during the induction period, these eleven subjects were not tested during the portion of the induction phase which followed their response. Following the single 24 hour challenge application, six subjects demonstrated slight to moderate erythema. Twenty-four hours after removal of the test material, mild to intense inflammatory changes were observed in 15 individuals. At 48 hours after removal, responses were still noted in 13 subjects. These responses were considered characteristic for allergic contact dermatitis.

In conclusion, the test substance, tested as a 60 % preparation in petrolatum, produced sensitization in 13/54 subjects who completed the study. No evidence of primary irritation was observed.This chemical was considered to be a strong skin sensitizer.