5',5'''-[ethylenebis(p-phenyleneazo)]bis[1',2'-dihydro-6'-hydroxy-4'-methyl-2'-oxo-1,3'-bipyridinium] dilactate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Remarks:

source of read across

Adequacy of study:

key study

Study period:

From 10th January to 14th February, 1991

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

1981

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Similar substance 01

IUPAC Name:

Similar substance 01

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK) Ltd., Manston, Kent, U.K.
- Age at study initiation: five to eight weeks old.
- Weight at study initiation: males weighed 150 - 162 g and the females 141 - 151 g.
- Fasting period before study: overnight fast immediately before dosing and for approximately two hours after dosing.
- Housing: animals were housed in groups of five by sex in solid-floor polypropylene cages with sawdust bedding.
- Diet: Rat and Mouse Expanded Diet No. 1, Special Diet Services Limited, Witham, Essex, U.K., ad libitum.
- Water: ad libitum.
- Acclimation period: minimum acclimatisation period of at least five days.

ENVIRONMENTAL CONDITIONS
- Temperature: 17 - 21 °C. On occasions the temperature was below the lower limit specified in the protocol (19 °C). This did not affect the purpose or integrity of the study.
- Relative humidity: 38 - 52 %
- Air changes: approximately 15 changes per hour.
- Photoperiod: the lighting was controlled by a time switch to give 12 hours continuous light and 12 hours darkness.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

TEST ITEM PREPARATION
For the purpose of the study, the test material was freshly prepared, as required, as a suspension at the appropriate concentration in distilled water. Homogeneity was assured by the use of a Silverson Homogeniser.
The composition and stability of the test material and the stability of the preparations were not determined.

DOSAGE MAIN STUDY
- Concentration: 500 mg/l
- Volume: 10 ml/kg

DOSAGES RANGE-FINDING STUDY
- Concentration: 500, 200, 20, 2.5 mg/l
- Volume: 10 ml/kg

Doses:

MAIN STUDY: 5000 mg/kg bw
RANGE-FINDING STUDY: 5000, 2000, 20, 25 mg/kg

No. of animals per sex per dose:

MAIN STUDY: 5 males and 5 females per dose per group.
RANGE-FINDING STUDY: 1 male and 1 female per dose per group.

Details on study design:

MAIN STUDY
- Duration of observation period following administration: deaths and overt signs of toxicity were recorded at 0.5, 1, 2 and 4 hours after dosing and then daily for 14 days.
- Frequency of observations and weighing: individual bodyweights were recorded on the day of treatment (Day 0) and on Days 7 and 14.
- Necropsy of survivors performed: at the end of the study animals were killed by cervical dislocation and subjected to gross pathological examination. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded. No tissues were retained.

RANGE-FINDING STUDY
- Aim: a range-finding study was performed using pre-selected dose levels to determine the highest dose that caused no deaths.
- Substance administration: all animals were dosed once only by gavage using a metal cannula attached to a graduated syringe. The volume administered to each animal was calculated according to its fasted bodyweight at the time of dosing.
- Observations: deaths and overt signs of toxicity were recorded at 0.5, 1, 2 and 4 hours after dosing and then daily for five days. Individual bodyweights were recorded on the day of dosing to allow calculation of individual treatment volumes. No necropsies were performed.
- Results: the results of the range-finding study indicated that the acute oral median lethal dose of the test material was greater than 5000 mg/kg bw. Based on this information, a dose level of 5000 mg/kg bodyweight was selected for the main study.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

MAIN STUDY
No deaths were recorded.

RANGE-FINDING STUDY
No deaths occurred.

Clinical signs:

MAIN STUDY
No signs of systemic toxicity were noted during the study. Brown coloured staining of the fur was commonly noted during the study.

RANGE-FINDING STUDY
Signs of systemic toxicity noted in the male treated with 5000 mg/kg were gasping respiration, noisy respiration, hunched posture, red/brown stains around mouth, lethargy and decreased respiratory rate.
There were no clinical signs of toxicity noted in the female treated with 5000 mg/kg or animals treated with 2000, 200 or 25 mg/kg

Body weight:

MAIN STUDY
AII animals showed expected gain in bodyweight during the study.

Gross pathology:

MAIN STUDY
No abnormalities were noted at necropsy.

Applicant's summary and conclusion

Interpretation of results:

other: not classified, according to the CLP Regulation (EC 1272/2008)

Conclusions:

LD50 (male and female) > 5000 mg/kg bw

Executive summary:

A study was performed to assess the acute oral toxicity of the test material in the Sprague-Dawley strain rat. The method used followed that described in the OECD guideline 401.

Following a range-finding study, a group of ten fasted animals (five males and five females) was given a single oral dose of test material, as a suspension in distilled water at a dose level of 5000 mg/kg bodyweight. The animals were observed for fourteen days after the day of dosing and were then killed for gross pathological examination. There were no deaths. No signs of systemic toxicity were noted during the study. All animals showed expected gain in bodyweight during the study. No abnormalities were noted at necropsy. The acute oral median lethal dose Sprague-Dawley strain rat was found to be higher than 5000 mg/kg bw.

Conclusion

LD50 (male and female) > 5000 mg/kg bw