Disodium 7-[(4-amino-3-methoxyphenyl)azo]naphthalene-1,3-disulphonate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Remarks:

limited documentation regarding composition of test material

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Disodium 7-[(4-amino-3-methoxyphenyl)azo]naphthalene-1,3-disulphonate

EC Number:

265-529-3

EC Name:

Disodium 7-[(4-amino-3-methoxyphenyl)azo]naphthalene-1,3-disulphonate

Cas Number:

65151-26-0

Molecular formula:

C17H15N3O7S2.2Na

IUPAC Name:

disodium 7-[(4-amino-3-methoxyphenyl)diazenyl]naphthalene-1,3-disulfonate

Test animals

Species:

rat

Strain:

Sprague-Dawley

Remarks:

Crl: CD* (SD) IGS BR

Sex:

male/female

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

All animals were dosed once; the test substance was administered orally as a solution in distilled water

Doses:

200 and 2000 mg/kg bw

No. of animals per sex per dose:

Groups of fasted animals were treated as follows:

Dose Level(mg/kg bw) Number of Rats
2000 3 females
200 3 females
200 3 males

Control animals:

no

Details on study design:

2000 mg/kg was chosen as the starting dose.

All animals were dosed once only. The volume administered to each animal was calculated according to the fasted body weight at the time of dosing. Treatment of animals was sequential.
The animals were observed for deaths and clinical signs 30 minutes, 1, 2 and 4 hours after dosing and subsequently once daily for 14 days.
Individual body weights were recorded prior to dosing and 7 and 14 days after treatment.
All animals were subjected to gross necropsy

Statistics:

not necessary

Results and discussion

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LD50

Effect level:

>= 300 - <= 500 mg/kg bw

Based on:

test mat.

Remarks on result:

other: according to the conclusion of the author of the study report

Effect levels 2

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 200 - < 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: as derived by the assessor of the study report

Mortality:

All animals treated with 2000 mg/kg bw were found death during the day of dosing. No deaths were noted at a dose level of 200 mg/kg bw.

Clinical signs:

other: signs of systemic toxicity noted in females were ataxia, lethargy, hunched posture, decreased respiratory rate, laboured respiration and dark orange staining of the feces and urine. No signs of systemic toxicity were noted in males treated with 200 mg/kg

Gross pathology:

For the 200 mg/kg bw dose group no abnormalities were noted at necropsy; for the 2000 mg/kg dose group see table 3 below

Any other information on results incl. tables

Table 1     Individual Clinical Observations and Mortality Data

Dose Level mg/kg	Animal Number and Sex	Effects Noted After Dosing (Hours)				Effects Noted During Period After Dosing (Days)
		½	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
200	2-0 Female	0	0	0	FU	HFU	H	0	0	0	0	0	0	0	0	0	0	0	0
	2-1 Female	0	0	0	FU	HFU	H	0	0	0	0	0	0	0	0	0	0	0	0
	2-2 Female	0	0	0	FU	HFU	H	0	0	0	0	0	0	0	0	0	0	0	0
	3-0 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-1 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-2 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0=   No signs of systemic toxicity

H =  Hunched posture

F =   Dark orange stained feces

U =  Dark orange stained urine

Table 2     Individual Body Weights and Body Weight Changes

Dose Level mg/kg bw	Animal Number and Sex	Body Weight (g) at Day			Body Weight Gain (g) During Week
		0	7	14	1	2
200	2-0 Female	211	234	256	23	22
	2-1 Female	229	252	256	23	4
	2-2 Female	218	249	270	31	21
	3-0 Male	246	319	374	73	55
	3-1 Male	253	321	371	68	50
	3-2 Male	231	296	351	65	55

Table 3     Individual Necropsy Findings

Dose Level mg/kg bw	Animal Number and Sex	Time of Death	Macroscopic Observations
2000	1-0 Female	4 hours after dosing	lungs and gastric mucosa: haemorrhagic; liver and kidneys: dark; small and large intestine: red/orange liquid present
	1-1 Female	4 hours after dosing	lungs and gastric mucosa: haemorrhagic; liver and kidneys: dark; small and large intestine: red/orange liquid present
	1-2 Female	4 hours after dosing	lungs and gastric mucosa: haemorrhagic; liver and kidneys: dark; small and large intestine: red/orange liquid present

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

Considering that all animals treated with 2000 mg/kg bw were found dead and that no deaths were noted at a dose level of 200 mg/kg bw. the acute oral median lethal dose (LD50) between 300 and 500 mg/kg body weight derived by the author of the report was inexplicable without further explanation. Thus the actual value was considered to be above 200 and below 2000 mg/kg bw.. Taking this into account and applying the CLP translation table (ANNEX VII, Table 1.1) a classification as Acute Tox. Cat 4, H302 was considered to be adequate.

Executive summary:

Introduction

The study was performed to assess the acute oral toxicity of the test item in the Sprague-Dawley rat.

Methods

A group of three fasted females was treated with the test item at a dose level of 2000 mg/kg body weight. This was followed by a further group of three fasted females and three males respectively at a dose level of 200 mg/kg bw. Dosing was performed sequentially.

The test item was administered orally as a solution in distilled water. Clinical signs and body weight development were monitored during the study. All animals were subjected to gross necropsy.

Results

Mortality. All animals treated with 2000 mg/kg bw died.

Clinical Observations. Hunched posture and dark orange stained feces and urine were noted up to day 3 in females exclusively. 

Body Weight. All animals of the 200 mg/kg dose group showed expected body weight gain.

Necropsy. No abnormalities were noted at necropsy in the 200 mg/kg bw dose group. In all animals of the 2000 mg/kg bw dose group haemorrhagic lungs and gastric mucosa, dark lung and kidneys and red/orange liquid present in small and large intestine were observed.

Conclusion by the author of the report

According to the results of the study the acute oral median lethal dose (LD₅₀) of the test item in the female Wistar strain rat was estimated to be between 300 and 500 mg/kg bwt.