m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Study conducted prior to GLP, no guideline followed as none was available in 1982 (OECD 401: 1987). However, the available information is documented sufficiently and allows the conclusion that the study was properly conducted with a scientifically acceptable method.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

no

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid

EC Number:

268-387-0

EC Name:

m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid

Cas Number:

68083-38-5

Molecular formula:

C10H11N3O3S

IUPAC Name:

3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Breeder: Winkelmann, Borchen
- Age at study initiation: 9-14 weeks
- Weight at study initiation: 182 g (average males) and 170 g (average females)
- Housing: In groups of five in Makrolon cages type III on low-dusting wood pellets
- Diet (e.g. ad libitum): Altromin R 1324 (Altromin GmbH und Co KG, Lage) ad libitum
- Water (e.g. ad libitum): tap water ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 1.5 °C
- Humidity (%): 60 ± 5%
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

polyethylene glycol

Details on oral exposure:

VEHICLE
- Amount of vehicle (if gavage): 20mL/kg bw

Doses:

4000 mg/kg bw (5000 mg/kg bw could not be applied)

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: several times on application day, otherwise twice a day for clinical symptoms, weighing on day 0 and 14
- Examinations performed: clinical signs, body weight, autopsy (randomly)

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 4 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: No animal died during study duration.

Any other information on results incl. tables

The dose of 4 g/kg bw was tolerated without symptoms, no animal died; no gross pathological findings.

Applicant's summary and conclusion

Interpretation of results:

other: EU-GHS criteria not met

Conclusions:

The study was conducted similar to OECD guideline 401 on the registered substance itself [1982 prior to GLP, no guideline followed as none was available (OECD 401: 1987)]. The available information is documented sufficiently and allows the conclusion that the study was properly conducted with a scientifically acceptable method. Hence, the results can be considered as sufficiently reliable to assess the acute oral toxicity in rats. The determined LD50 value is > 4000 mg/kg bw, as none of the animals died after gavage of the highest dose. The result is suitable to determine the classification of the substance; according to Regulation (EC) No. 1272/2008, the substance does not need to be classified as acute toxic cat. IV or higher.

Executive summary:

In an acute oral toxicity study (no GLP) from 1982 similar to the later OECD Guideline 401, groups of 9-14 weeks old Wistar  rats (5/sex) were given an oral dose of 4000 mg/kg bw via gavage of the test substance formulated in Lutrol and observed for 14 days.

 

Oral LD50> 4000 mg/kg bw

None of the animals died during the test or showed signs of toxicity. Hence, the test substance is of low toxicity based on the LD50 and does not need to be classified as acute toxic cat. IV or higher.