Sodium 4(-2-hydroxy-1-naphthylazo)naphthalenesulphonate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 11 Feb. 2004 to 3 Mar. 2004

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method B.1 bis (Acute Oral Toxicity - Fixed Dose Procedure)

Version / remarks:

29 December 1992

GLP compliance:

yes

Test type:

fixed dose procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Sodium 4(-2-hydroxy-1-naphthylazo)naphthalenesulphonate

EC Number:

216-760-3

EC Name:

Sodium 4(-2-hydroxy-1-naphthylazo)naphthalenesulphonate

Cas Number:

1658-56-6

Molecular formula:

C20H13N2NaO4S

IUPAC Name:

NA

Test material form:

solid: particulate/powder

Test animals

Species:

rat

Strain:

Sprague-Dawley

Remarks:

Hsd

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Interfauna Ibérica, S.L. [Ctra. Sant Miquel del Fai, km 3, Apartado 38, 08182-Sant Feliu de Codines, Barcelona (Spain)]
- Age at study initiation: five weeks old.
- Weight at study initiation:
preliminary test: ♀ 117-122 g
main test: ♂ 125 - 136 g; ♀ 112 - 124 g
- Fasting period before study: during the study period, the food was withdrawn approximately 16-18 hours before the administration. After 3-4 hours following treatment, the rats were once more allowed free access to food.
- Housing: in Makrolon cages (59.0 x 38.5 x 20.0 cm) with Ultrasorb sawdust bedding.
- Diet: the rats had free access to a standard diet for rats, SAFE A04C (Scientific Animal Food Engineering, 91360-Villemoisson sur Orge, France, Batch: 31118).
- Water: tap. water for drinking was available ad libitum in bottles.
- Acclimation period: 7 days, during which animals had veterinary examination.

ENVIRONMENTAL CONDITIONS
-Temperature: 21 - 24 °C
-Humidity: 30-60 % (occasionally 70 %)
-Photoperiod: 12 hours of light (7:00 am to 7:00 pm) and 12 hours of darkness every 24 hours.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Volume administration: 10 ml/kg

Doses:

Preliminary study: 500 and 2000 mg/kg b.w
Main study: 2000 mg/kg b.w

No. of animals per sex per dose:

2 females in the preliminary test and 5 per sex per single dose in the main test

Control animals:

no

Details on study design:

- Duration of observation period following administration: 7 day for the preliminary test and 14 days for the main test.
- Frequency of observations: the day of administration frequently and during the following days twice a day both for the preliminary test and the main test.
- Observation: included, but were not limited to, changes in skin or fur, eyes and mucous membranes, respiratory, circulatory, central nervous and autonomic nervous systems, somatomotor activity and behaviour in order to note any possible clinical response.
- Frequency of weighing: before administration, daily on the next three days, and afterwards at weekly intervals, before sacrifice at the end of the study period.
- Sacrifice: by intraperitoneal injection of sodium pentobarbital.
- Necropsy: included the inspection of the intact animal and all superficial tissues, followed by the observation of the viscera of the cranial, thoracic and abdominal cavities.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

not determinable due to absence of adverse toxic effects

Mortality:

No mortality was recorded both in preliminary and main studies.

Clinical signs:

PRELIMINARY TEST
Both animals showed hunched back and ataxia during the day oftreatment. The animal treated at the dose of 500 mg/kg also showed piloerection for the 15 minutes after the treatment. The animal treated at 2000 mg/kg showed red pasty faeces, similar to the colour of the test item, from 3-4 hours after the administration.
The day after the treatment, the animal treated at 2000 mg/kg showed red faeces.
No clinical signs were recorded in the animals treated at the doses of 500 and 2000 mg/kg, from the second day ofthe observation period.

MAIN TEST
All the animals treated at 2000 mg/kg presented hunched back and ataxia from 5-30 minutes after the administration in most of the cases. In all them diarrhoea and/or red pasty faeces, similar to the colour of the test item, was also recorded from 2-3 hours after the treatment. The day after the administration, red coloured faeces were still observed in three males and two females.
No clinical signs were recorded in the animals administered at the dose of 2000 mg/kg from the second day of the observation period.

Body weight:

PRELIMINARY TEST
The body-weight gain of the animals treated at these doses was normal. At the beginning of the test, the animals weighed 122 and 117 g and at the end of the observation period, seven days after the administration, they weighed 174 and 157 g, respectively.

MAIN TEST
The mean body-weight gain was normal.

Gross pathology:

No macroscopic alterations were detected during the necropsies done on all the animals of the Main Study.

Applicant's summary and conclusion

Interpretation of results:

other: not classified according to the CLP Regulation (EC) No 1272/2208

Conclusions:

The LD50 (oral) was found to be greater than 2000 mg/kg bw.

Executive summary:

The substance was tested for acute toxicity, according to the EU Method B.1. bis (Fixed Dose Procedure). In the Preliminary Study the test item was administered to one female at the dose of 500 mg/kg. As no mortality was recorded in this animal, another female was administered at the dose of 2000 mg/kg and also survived the treatment. In the Main Study, five males and five females were treated at the dose of 2000 mg/kg. No mortality was recorded and no signs of toxicity were observed during the experiment.

The LD50 (oral) was found to be greater than 2000 mg/kg bw.