Hydrogen bis[2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)]chromate(1-)

Endpoint summary

Description of key information

LD50(oral) > 5000 mg/kg bw

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

other: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

From November 19, 1982 to December 7,1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Remarks:

The complete read across justification is detailed in section 13. Source study has reliability 2.

Qualifier:

according to guideline

Guideline:

EPA OPP 81-1 (Acute Oral Toxicity)

Version / remarks:

1978

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

1981

GLP compliance:

no

Test type:

standard acute method

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Kleintierfarm Madoerin AG, 4414 Fuellinsdorf/Switzerland
- Age at study initiation: male, 7 weeks; female, 9 weeks
- Weight at study initiation: male, 211-252 g, female 168-187 g
- Housing: animals were caged in group of 5 in Macrolon cages type 3 with wire mesh tops and standardised granulated soft wood bedding
- Diet: pelleted standard kliba 23/341/1, rabbit maintenance diet defined for acceptable contaminant level, ad libitum
- Water: tap water, ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature: 22 ± 2 °C
- Humidity: 55 ± 10 %
- Photoperiod: 12 hours cycle dark/light

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Details on oral exposure:

VEHICLE 2 % solution of CMC(carboxymethylcellulose natrium salt purum) in distilled water:
- 10 ml at 1000 mg/kg bw
- 20 ml at 5000 mg/kg bw

Doses:

1000, 5000 mg/kg bw

No. of animals per sex per dose:

5 per sex per dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations:
1. bodyweights: at day of administration and day 7 and 14 after administration;
2. mortality: 5 times during the first day and daily thereafter;
3. symptoms on general behaviour, respiration, eye, nose, motility, body position, motor susceptibility, skin: 5 times at day 1 and then daily for the nature, onset, severity and duration of all gross or visible toxic or pharmacological effects as well as rate and time of death.
- Necropsy of survivors performed: yes

Statistics:

The logit model could not be applied to the observed rates of death. The LD50 was calculated without use of a statistical model by estimation.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Sex:

male/female

Dose descriptor:

LD0

Effect level:

ca. 5 000 mg/kg bw

Based on:

test mat.

Mortality:

None.

Clinical signs:

other: At the dose of 1000 mg/kg bw only ruffled fur was noted in male and female rats. This symptom disappeared within 14-day observation period. At the dose of 5000 mg/kg bw dyspnoea, curved body position and ruffled fur were noted in male and female rats. The

Gross pathology:

No pathological changes.

Interpretation of results:

other: Not classified according to the CLP Regulation (EC n. 1272/2008)

Conclusions:

The acute oral LD50 in rats of both sexes observed over period of 14 days was estimeted to be greater than 5000 mg/kg bw.

Executive summary:

Method

Acute oral toxicity study in rats administered at doses of 1000 and 5000 mg/kg bw. 5 animals per sex per dose were used and observed for 14 days after dosing.

Results

The following death rate was observed:

0 % at 1000 mg/kg

0 % at 5000 mg/kg

The acute oral LD50 in rats of both sexes observed over period of 14 days was greater than 5000 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

No information is available on the substance itself, i.e. Solvent Orange 062 acid. However, a study on a read across substance, i.e. Solvent Orange 062 sodium salt containing some amounts of its acid form, was available and used for the assessment. A detailed description of the read across process was attached in section 13.

Acute oral toxicity to rats of test substance was tested at a concentration of 1000 and 5000 mg/kg. No mortality was recorded and symptoms (dyspnoea, curved position and ruffled fur) disappeared within the 14 -day observation period. Thus, a LD0 of 5000 mg/kg was established.

Justification for classification or non-classification

According to the CLP Regulation (EC 1272/2008), substances can be allocated to one of four toxicity categories based on acute toxicity by the oral, dermal or inhalation route according to numeric criteria. Acute toxicity values are expressed as (approximate) LD50 (oral, dermal) or LC50 (inhalation) values or as acute toxicity estimates (ATE).

 

The oral LD50 value was established to be greater than 5000 mg/kg body weight, therefore the test substance is above the classification threshold for acute oral toxicity (Category 4: 300 < ATE ≤ 2000 mg/kg).