Methyl N-[4-[(2-bromo-6-chloro-4-nitrophenyl)azo]phenyl]-N-(3-methoxy-3-oxopropyl)-β-alaninate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

December 1978

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

no

Remarks:

Study pre-dates GLP

Type of study:

not specified

Justification for non-LLNA method:

Study available is over 12 years old.

Test material

Test material information

Constituent 1

Reference substance name:

Methyl N-[4-[(2-bromo-6-chloro-4-nitrophenyl)azo]phenyl]-N-(3-methoxy-3-oxopropyl)-β-alaninate

EC Number:

261-874-9

EC Name:

Methyl N-[4-[(2-bromo-6-chloro-4-nitrophenyl)azo]phenyl]-N-(3-methoxy-3-oxopropyl)-β-alaninate

Cas Number:

59709-38-5

Molecular formula:

C20H20BrClN4O6

IUPAC Name:

methyl N-[4-[(2-bromo-6-chloro-4-nitrophenyl)azo]phenyl]-N-(3-methoxy-3-oxopropyl)-β-alaninate

Test material form:

solid: granular

Details on test material:

Disperse Brown 19

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

female

Details on test animals and environmental conditions:

Ten young female Hartley-Dunkin albino guinea pigs obtained from Redfern Animal Breeders, Jasons Farm, Old Hay, Brenchley, Kent were used for this study. They were conditioned to the laboratory environment for not less than 6 days and on the day before initial treatment they were weighed. At this time the body weights of the guinea pigs were within the range 300 - 430 g. Three animals were marginally over the body weight range required by the protocol.

Diet
The animals were allowed free access to amins water and food (Guinea pig Diet-Standard supplemented with Vit. C., BP Nutrition (U.K.) Ltd., Stepfield, Witham, Essex).

Environment
All animals were housed in a single air-conditioned room maintained at a temperature of 22 + 3°C, relative humidity 50 + 10% and exposed to natural lighting conditions. They were caged in groups of 2 in grid floor polypropylene boxes.

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, open

Vehicle:

N,N-dimethylformamide

Concentration / amount:

0.1 ml of a 10% w/v solution

Day(s)/duration:

3 days

Adequacy of induction:

not specified

Challenge

No.:

#1

Route:

epicutaneous, open

Vehicle:

N,N-dimethylformamide

Concentration / amount:

0.2 ml
10% w/v, 1% w/v and 0.1% w/v

Day(s)/duration:

1 day

No. of animals per dose:

6 animals

Details on study design:

The test article (0.1 ml of a 10% w/v solution in dimethylformamjde) was applied daily by means of a glass syringe to the outer surface of the ears of 6 guinea pigs (animal numbers 1 - 6) for three days
(days 1, 2 and 3). On Day 8, 0.2 ml of the challenge solutions (10% w/v, 1% w/v and 0.1% w/v in dimethylformamide) was applied topically to 1 cm diameter circular areas on the clipped flanks of each of the same 6 animals. Solutions of test article were also applied in the same way on Day 8 to the clipped flanks of control animals (animal numbers 7 - 10) which had no previous treatment on the ears. The-applications were made on both flanks of all 10 guinea pigs, with each concentration being applied to each flank. The highest concentration was applied closest to the posterior end of the animal while the lowest concentration was applied nearest the anterior end.
The erythema produced on each site was assessed 24 hours later (Day 9) and graded on a 6 point scale.

Challenge controls:

The highest concentration was applied closest to the posterior end of the animal while the lowest concentration was applied nearest the anterior end.

Positive control substance(s):

not specified

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

10% w/v

No. with + reactions:

0

Total no. in group:

6

Clinical observations:

None specified

Remarks on result:

no indication of skin sensitisation

Results 2

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

1% w/v

No. with + reactions:

0

Total no. in group:

6

Clinical observations:

None specified

Remarks on result:

no indication of skin sensitisation

Results 3

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

0.1% w/v

No. with + reactions:

0

Total no. in group:

6

Clinical observations:

None specified

Remarks on result:

no indication of skin sensitisation

Results 4

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

10% w/v

No. with + reactions:

0

Total no. in group:

4

Clinical observations:

None specified

Remarks on result:

no indication of skin sensitisation

Results 5

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

1.0% w/v

No. with + reactions:

0

Total no. in group:

4

Clinical observations:

None specified

Remarks on result:

no indication of skin sensitisation

Results 6

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

0.1% w/v

No. with + reactions:

0

Total no. in group:

4

Clinical observations:

None specified

Remarks on result:

no indication of skin sensitisation

Any other information on results incl. tables

Skin reactions at challenge phase

Test article: Disperse Brown 19

Vehicle: dimethylformamide

Concentration: 10% w/v, 1% w/v and 0.1% w/v

Animal number and sex	Weight (g)	Skin reactions assessed at 24 hours after application
		10% w/v	1% w/v	0.1% w/v
1 2 3 4 5 6 7 control 8 control 9 control 10 control	410 410 430 321 308 318 340 355 344 351	0 0 0 0 0 0 0 0 0 0	0 0 0 0 0 0 0 0 0 0	0 0 0 0 0 0 0 0 0 0

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

No erythema was noted in any of the test or control animals. The test article was not considered to be a strong sensitiser.

Executive summary:

A study was carried out to determine the skin-sensitising potential of test article in the albino guinea pig. The study was performed in accordance with Standard Operating Procedures.

 

Ten young female Hartley-Dunkin albino guinea pigs were used for this study. They were conditioned to the laboratory environment for not less than 6 days and on the day before initial treatment they were weighed. At this time the body weights of the guinea pigs were within the range 300 - 430 g. Three animals were marginally over the body weight range required by the protocol.

 

The test article (0.1 ml of a 10% w/v solution in dimethylformamjde) was applied daily by means of a glass syringe to the outer surface of the ears of 6 guinea pigs (animal numbers 1 - 6) for three days (days 1, 2 and 3).

On Day 8, 0.2 ml of the challenge solutions (10% w/v, 1% w/v and 0.1% w/v in dimethylformamide) was applied topically to 1 cm diameter circular areas on the clipped flanks of each of the same 6 animals. Solutions of test article were also applied in the same way on Day 8 to the clipped flanks of control animals (animal numbers 7 - 10) which had no previous treatment on the ears. The applications were made on both flanks of all 10 guinea pigs, with each concentration being applied to each flank.

The highest concentration was applied closest to the posterior end of the animal while the lowest concentration was applied nearest the anterior end.

The erythema produced on each site was assessed 24 hours later (Day 9).

 

Results

No erythema was noted in any of the test or control animals. The test article was not considered to be a strong sensitiser.