Disodium 7-amino-4-hydroxy-3-[[4-[(4-sulphonatophenyl)azo]phenyl]azo]naphthalene-2-sulphonate

Endpoint summary

Description of key information

The acute toxicity of the substance has been determined in adequate studies in the rat following oral and dermal administration. No studies are available for inhalation.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1981

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

no

Test type:

acute toxic class method

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

Adult, young, albino, Wistar ITA177 SPF strain are used. Rats have been bred and kept in rooms with spf conditioning. The temperature is 24+-1 ° C and the humidity is 65+-5%.
The lighting is artificial, following periods of light and darkness of 12 h.

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Details on oral exposure:

All rats remain fasting approximately 18 hours before and 4 hours after administration. The rest of the time they received UAR D-04 sterilized feed and demineralised water "as libitum".
Rats are administered orally by means of a esophageal probe, the product suspended or dissolved in a solution of 1% tween 80 and 2% carboxymethylcellulose in distilled water.
Liquid products, if possible, are given undiluted.
Dose levels are chosen in progression and the products are administered according to the individual body weights of the rats (mg / kg or ml / kg).
The maximum dose used is 16 mg / kg or 16 ml / kg. The volume administered when using vehicle is 10 ml / kg. At high doses, the volume can be increased to a maximum of 40 ml / kg to facilitate the suspension of the product.
The control group receives only vehicle at the maximum volume administered.

Doses:

4 mg/kg bw, 8 mg/kg bw, 11.3 mg/kg bw, 16 mg/kg bw

No. of animals per sex per dose:

10 animals per dose

Control animals:

yes

Details on study design:

Body weights are recorded for each rat immediately prior to administration, and thereafter at weekly intervals.
Animals are often observed on the day of the administration, and then at least once a day for 14 days.
Symptoms of reaction to treatment are recorded in terms of approximate time of onset, duration and intensity.
The circumstances of each death are recorded and the autopsy performed, which includes the opening of the abdominal and thoracic cavities, as well as the cranial cavity if the observations indicate neurotoxic activity. The organs are examined microscopically and the observed alterations are noted.
All surviving animals at the end of the observation period are sacrificed and undergo the same autopathic examination.
The 14-day observation period will be extended if the general condition of the animals is not considered satisfactory or if delayed toxicity is noted.
The LD50 value is calculated from the mortality data found using the method of Litchfield and Wilcoxon.

Preliminary study:

The preliminary study has an experimental design similar to the one of the study, but using a smaller number of animals (2 males and 2 females per group).
If the LD50 is found to be equal to or greater than 16 g / kg (16 ml / kg in the case of liquid) during the preliminary study, the exact value of LD50 is not determined.
If LD50 is found to be only slightly lower than 16 g / kg (16 ml / kg in the case of liquids), its value is determined even if four dose levels are not administered.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

14.8 mL/kg bw

Based on:

act. ingr.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

2 516 mg/kg bw

Based on:

act. ingr.

Mortality:

The day after the adminsitration the observed mortality was:
Dose 16ml/kg: 60% (4 males, 2 females)
Dose 11,3 ml/kg: 20% (1 male, 1 female)
Dose 8 ml/kg: 10% (1 male)
Dose 4 ml/kg: 0%

Clinical signs:

other: Not observed

Gross pathology:

Not observed

Interpretation of results:

GHS criteria not met

Conclusions:

The substance has been found to have a LD50 of 14.8 (11.3-19.3) ml / kg when administered orally.
Rats died on the first day after administration without showing external signs of toxicity. There were no macroscopic alterations at autopsies.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 516 mg/kg bw

Quality of whole database:

The study is a not GLP compliant one, but the Klimisch score is 1

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Quality of whole database:

There isn’t any test available for acute inhalation toxicity. According to the column 2 of annex VIII, the choice for the second route will depend on the nature of the substance and the likely route of human exposure. Information on dermal toxicity is provided, as considered more relevant for this substance.

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

yes

Specific details on test material used for the study:

For the purpose of the study the test item was ground to a fine powder using a mortar and pestle and weighed out according to each animal’s individual body weight. The test item was moistened with distilled water prior to application.
The absorption of the test item was not determined.

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

3.3.1 Animal Information
Five male and five female Wistar (RccHanTM:WIST) strain rats were supplied by Envigo RMS (UK) Limited, Oxon, UK. On receipt the animals were randomly allocated to cages. The females were nulliparous and non-pregnant. After an acclimatization period of at least 5 days the animals were selected at random and given a number unique within the study by indelible ink-marking on the tail and a number written on a cage card. At the start of the study the animals weighed at least 200 g, and were 8 to 12 weeks of age. The weight variation did not exceed ±20% of the mean weight for each sex.
3.3.2 Animal Care and Husbandry
The animals were housed in suspended solid floor polypropylene cages furnished with woodflakes. The initial two animals were housed individually throughout the study. The further group of eight animals (four male and four female) were housed individually during the 24-Hour exposure period and in groups of four, by sex, for the remainder of the study. Free access to mains drinking water and food (2014C Teklad Global Rodent diet supplied by Envigo RMS (UK) Limited, Oxon, UK) was allowed throughout the study. The diet, drinking water and bedding were routinely analyzed and were considered not to contain any contaminants that could reasonably be expected to affect the purpose or integrity of the study.
The temperature and relative humidity were set to achieve limits of 19 to 25ºC and 30 to 70% respectively. The rate of air exchange was at least fifteen changes per hour and the lighting was controlled by a time switch to give 12 hours continuous light and 12 hours darkness.
The animals were provided with environmental enrichment items which were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.

Type of coverage:

semiocclusive

Vehicle:

water

Details on dermal exposure:

Applied on an area of shorn skin (approximately 10% of the total body surface area).

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5 males, 5 females

Control animals:

no

Details on study design:

On the day before treatment the back and flanks of each animal were clipped free of hair.

In the absence of data suggesting the test item was toxic, one male and one female rat were initially treated with the test item at a dose level of 2000 mg/kg.

The appropriate amount of test item, moistened with distilled water, was applied as evenly as possible to an area of shorn skin (approximately 10% of the total body surface area). A piece of surgical gauze was placed over the treatment area and semi-occluded with a piece of self-adhesive bandage. The animals were caged individually throughout the study. Shortly after dosing the dressings were examined to ensure that they were securely in place.

After the 24-Hour contact period the bandage was carefully removed and the treated skin and surrounding hair wiped with cotton wool moistened with distilled water to remove any residual test item.

As no mortalities were noted a further group of animals (four males and four females) was similarly treated with the test item at a dose level of 2000 mg/kg body weight to give a total of five males and five females. The animals were caged individually for the 24-Hour exposure period. After the 24-Hour contact period the bandages were carefully removed and the treated skin and surrounding hair wiped with cotton wool moistened with distilled water to remove any residual test item. These animals were returned to group housing for the remainder of the test period.

The animals were observed for deaths or overt signs of toxicity 30 minutes, 1, 2 and 4 hours after dosing and subsequently once daily for 14 days.

After removal of the dressings and subsequently once daily for 14 days, the test sites were examined for evidence of primary irritation and scored according to the following scale:

EVALUATION OF SKIN REACTIONS:
Erythema and Eschar Formation
No erythema, 0
Very slight erythema (barely perceptible), 1
Well-defined erythema, 2
Moderate to severe erythema, 3
Severe erythema (beef redness) to slight eschar formation (injuries in depth), 4

Edema Formation
No edema, 0
Very slight edema (barely perceptible), 1
Slight edema (edges of area well-defined by definite raising), 2
Moderate edema (raised approximately 1 millimeter), 3
Severe edema (raised more than 1 millimeter and extending beyond the area of exposure),4

Any other skin reactions, if present were also recorded.
Individual body weights were recorded prior to application of the test item on Day 0 and on Days 7 and 14.
At the end of the study the animals were killed by cervical dislocation. All animals were subjected to gross necropsy. 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.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

no indication of skin irritation up to the relevant limit dose level

Mortality:

There were no deaths.

Clinical signs:

other: There were no signs of systemic toxicity.

Gross pathology:

No abnormalities were noted at necropsy

Other findings:

Dermal Irritation. No signs of dermal irritation were noted at the test sites of the two initial treated animals. Very slight erythema was noted at the test sites of the further group of eight animals. Other signs of dermal irritation noted were small superficial scattered scabs, glossy skin and scab lifting to reveal glossy skin

Interpretation of results:

GHS criteria not met

Conclusions:

The acute dermal median lethal dose (LD50) of the test item in the Wistar strain rat was found to be greater than 2000 mg/kg body weight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The study is a GLP compliant and has Klimisch score 1

Justification for classification or non-classification

Acute oral toxicity

Based on the results of acute oral toxicity testing, the substance has not to be classified for this hazard class following the criteria of the EU Regulation 1272/2008 (CLP Regulation). The criteria in CLP Regulation stablishes the limit for classification as Acute Tox Oral Category 4 in 2000 mg/kg, and the value obtained is >2000 mg/kg bw.

 

Acute inhalation toxicity

There isn’t any test available for acute inhalation toxicity. According to the column 2 of annex VIII, the choice for the second route will depend on the nature of the substance and the likely route of human exposure. Information on dermal toxicity is provided, as considered more relevant for this substance.

 

Acute dermal toxicity

Based on the results of acute dermal toxicity testing, the substance has not to be classified for this hazard class following the criteria of the EU Regulation 1272/2008 (CLP Regulation).The criteria in CLP Regulation stablishes the limit for classification as Acute Tox Dermal Category 4 in 2000 mg/kg, and this is the value obtained in the limit test conducted with the substance.