Isonicotinamide

Endpoint summary

Description of key information

LD50 (orl rat) > 875 mg/kg

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:

supporting study

Study period:

1995

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Not performed in GLP laboratory No indication of Guideline in report, but found to be similar to OECD Guideline 401 (Acute Oral Toxicity)

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

not specified

GLP compliance:

no

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: IFFA/CREDO (Saint-Germain sur l'Arbresle - France)
- Age at study initiation: about 6 weeks
- Weight at study initiation: around 150 g
- Fasting period before study: 15 to 20 hours
- Housing: dust free sawdust (Litalabo)
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 5 to 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22°C ± 2°C
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12 hours dark / 12 hours light

Route of administration:

oral: gavage

Vehicle:

other: 5% gommi arabicum

Details on oral exposure:

VEHICLE
- Amount of vehicle (if gavage): 1 ml for 100 g of body weight

MAXIMUM DOSE VOLUME APPLIED: 875 mg/kg

Doses:

The highest dose that could be set in suspension in gommi arabicum was 875 mg/kg

No. of animals per sex per dose:

10

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: day 0, 3, 7, 10 and 14
- Necropsy of survivors performed: no
- Other examinations performed: clinical signs, body weight

Statistics:

Calculation accordingly to Bliss model

Sex:

male

Dose descriptor:

LD50

Effect level:

> 875 mg/kg bw

Remarks on result:

not determinable because of methodological limitations

Mortality:

None at 875 mg/kg

Clinical signs:

other: No comportemental behaviour at 875 mg/kg

Interpretation of results:

study cannot be used for classification

Conclusions:

LD50 (orl, rat) is > 875 mg/kg
As there was no death observed at this dose, we could assume that LD50 (orl, rat) is > 2.000 mg/kg and in consequence, the substance should not be classified with regards to Acute toxicity by ingestion.
Danish (Q)SAR Database predicts a LD50 (orl, rat) at 2600 mg/kg/d (reliability Index: 0.74)

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed