4-aminoazobenzene

Carcinogenicity

Administrative data

Endpoint:

carcinogenicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable publication which meets basic scientific principles

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Rat skin carcinogenesis by topical applications of some azo dyes

Author:

Fare G.

Year:

1966

Bibliographic source:

Cancer Res 26: pp.2406-8

Reference 2

Reference Type:

secondary source

Title:

4-Aminoazobenzene. BUA-Stoffbericht 217

Author:

Beratergremium für Altstoffe (BUA).

Year:

1998

Bibliographic source:

BUA der Gesellschaft dt. Chemiker, S. Hirzel Wissenschaftliche Verlagsgesellschaft, Stuttgart.

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 451 (Carcinogenicity Studies)

Deviations:

yes

Remarks:

only one dose used, only one sex used, only 6 animals used

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

4-aminoazobenzene

EC Number:

200-453-6

EC Name:

4-aminoazobenzene

Cas Number:

60-09-3

Molecular formula:

C12H11N3

IUPAC Name:

4-[(E)-2-phenyldiazen-1-yl]aniline

Details on test material:

Aminoazobenzene: Recristallized prior to use

Test animals

Species:

rat

Strain:

other: Albino outbred from own breeding

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: own breeding
- Age at study initiation: 3 to 4 months old
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum

Administration / exposure

Route of administration:

dermal

Vehicle:

acetone

Details on exposure:

TEST SITE
- Area of exposure: between scapulae
- % coverage: no data
- Type of wrap if used: no data
- Time intervals for shavings or clipplings: Hair was shaved every 2 months in the early stages but much more frequently when tumors began to appear.

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 1 ml
- Concentration (if solution): 0.2% solution
- Constant volume or concentration used: yes


VEHICLE
- Amount(s) applied (volume or weight with unit): 1 ml
- Concentration (if solution): 100%


USE OF RESTRAINERS FOR PREVENTING INGESTION: no

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

mean time of treatment 123 weeks

Frequency of treatment:

twice per week

Post exposure period:

no post exposure period

Doses / concentrations

Remarks:

Doses / Concentrations:
1 ml of 0.2% solution in aceton
Basis:
analytical conc.

No. of animals per sex per dose:

6 male animals

Control animals:

yes, concurrent vehicle

Positive control:

no

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: No data

DETAILED CLINICAL OBSERVATIONS: No data

DERMAL IRRITATION (if dermal study): Yes

BODY WEIGHT: No data

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: No

CLINICAL CHEMISTRY: No

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes

Results and discussion

Results of examinations

Details on results:

Result (carcinogenicity): positive

Effect levels

Dose descriptor:

conc. level:

Effect level:

0.2 other: %

Sex:

male

Basis for effect level:

other: Skin tumors

Remarks on result:

other: Effect type: carcinogenicity (migrated information)

Any other information on results incl. tables

6 male rats treated twice weekly with Aminoazobenzene:

Mean time 1st lesion noted: 97th week

Mean length of treatment: 123 weeks

Tumor incidence: 0/6 ear duct; 6/6 skin

Total yield of skin tumors in group, postmortem: 5 epidermoid cysts; 4 squamous carcinoma; 8 basal carcinoma; 2 anaplastic carcinoma; 1 squamous papiloma; 3 miscellaneous