4-[[2-methoxy-4-[(4-nitrophenyl)azo]phenyl]azo]phenol

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From March 25, 1976 to April 22, 1976

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:

1976

Report date:

1976

Materials and methods

Principles of method if other than guideline:

Female SPF Wistar rats were administered a single dose of the test substance as a liquid dispersion (20% purity) via gavage. Rats were not fed from 16 h pre-test to 2 h post-application. There were 10 rats per group, exposed to nominal concentrations of 1250, 2500, 4000, 6300 and 10000 mg/kg bw (equivalent to 250, 500, 800, 1260 and 2000 mg a.i./L). The animals were then observed during 14 days for mortality and clinical signs. Bodyweights were recorded weekly. Moribund rats were dissected and evaluated macroscopically. The same procedure was carried out for all remaining rats at the end of the study.

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4-[[2-methoxy-4-[(4-nitrophenyl)azo]phenyl]azo]phenol

EC Number:

243-325-5

EC Name:

4-[[2-methoxy-4-[(4-nitrophenyl)azo]phenyl]azo]phenol

Cas Number:

19800-42-1

Molecular formula:

C19H15N5O4

IUPAC Name:

4-[[2-methoxy-4-[(4-nitrophenyl)azo]phenyl]azo]phenol

Test material form:

liquid

Remarks:

aqueous preparation of test substance

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

Body weight: 80 - 115g

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Doses:

1250, 2500, 4000, 6300, 10000 mg/kg (concentration (%): 25)

No. of animals per sex per dose:

10

Control animals:

no

Details on study design:

Post - observation: 14 days

Statistics:

Probit analysis

Results and discussion

Effect levels

Effect levels 1

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

4 529 mg/kg bw

Based on:

test mat.

95% CL:

ca. 3 511 - ca. 5 843

Effect levels 2

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

905 mg/kg bw

Based on:

act. ingr.

Remarks:

20% test substance purity

95% CL:

ca. 702 - ca. 1 169

Mortality:

Doses (mg/kg bw):
- 1250: 0/10
- 2500: 2/10
- 4000: 5/10
- 6300: 5/10
- 10000: 10/10

Clinical signs:

other: Directly after gavage, a yellow discoloration of the urine was observed. Moribund animals showed irregular breathing and disturbance of their balance.

Gross pathology:

No macroscopic lesions were found except for a rusty brown discoloration in the stomach and intestine.

Applicant's summary and conclusion

Executive summary:

A study was conducted to determine the acute oral toxicity of the test substance to rats. Female SPF Wistar rats were administered a single dose of the test substance as a liquid dispersion (20% purity) via gavage. Rats were not fed from 16 h pre-test to 2 h post-application. There were 10 rats per group, exposed to nominal concentrations of 1250, 2500, 4000, 6300 and 10000 mg/kg bw (equivalent to 250, 500, 800, 1260 and 2000 mg a.i./L). The animals were then observed during 14 days for mortality and clinical signs. Bodyweights were recorded weekly. Moribund rats were dissected and evaluated macroscopically. The same procedure was carried out for all remaining rats at the end of the study. Directly after gavage, a yellow discoloration of the urine was observed. Moribund animals showed irregular breathing and disturbance of their balance. At test end, no macroscopic lesions were found except for a rusty brown discoloration in the stomach and intestine. Bodyweight data results were not discussed. Under the study conditions, the LC50 was determined to be 4529 mg/kg bw, equivalent to 905 mg a.i./kg bw (Hollander, 1986).