Registration Dossier
Registration Dossier
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EC number: 203-565-3 | CAS number: 108-26-9
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:
- other: OECD Guideline study, non GLP
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 1 982
- Report date:
- 1982
Materials and methods
Test guideline
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 401 (Acute Oral Toxicity)
- GLP compliance:
- no
- Test type:
- standard acute method
- Limit test:
- yes
Test material
- Reference substance name:
- 2,4-dihydro-5-methyl-3H-pyrazol-3-one
- EC Number:
- 203-565-3
- EC Name:
- 2,4-dihydro-5-methyl-3H-pyrazol-3-one
- Cas Number:
- 108-26-9
- Molecular formula:
- C4H6N2O
- IUPAC Name:
- 2,4-dihydro-5-methyl-3H-pyrazol-3-one
Constituent 1
Test animals
- Species:
- rat
- Strain:
- Wistar
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: Dr. Thomae GmbH, Biberach, Germany
- Age at study initiation: about 12 weeks
- Weight at study initiation: mean: males: 190 g, females: 170 g
- Fasting period before study: yes: 16 hours before application of test substance
- Housing: five animals per cage
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least on week
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 26
- Humidity (%): 45- 75
- Air changes (per hr): 15 - 20
- Photoperiod (hrs dark / hrs light): 12/12
Administration / exposure
- Route of administration:
- oral: gavage
- Vehicle:
- CMC (carboxymethyl cellulose)
- Remarks:
- 0.5% aqueous solution of CMC
- Details on oral exposure:
- VEHICLE
- Concentration in vehicle: 50%
MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg - Doses:
- 5000 mg/kg bw
- No. of animals per sex per dose:
- 5
- Control animals:
- no
- Details on study design:
- - Duration of observation period following administration: 18 days
- Frequency of observations and weighing: Recording of signs and symptoms: < 15 min, 15 min, 30 min, 1 h, 2 h, 4 h and 5 h after administration, then once on working days. Check for moribund or dead animals twice each working days and once on public holidays.
- Necropsy of survivors performed: yes
Results and discussion
Effect levels
- Sex:
- male/female
- Dose descriptor:
- LD50
- Effect level:
- > 5 000 mg/kg bw
- Remarks on result:
- other: No mortality was observed.
- Mortality:
- None
- Clinical signs:
- other: Dyspnea, apathy, staggering (females only), urine orange-coloured, ruffled fur, poor general state
- Gross pathology:
- Sacrificed animals: organs without findings
Applicant's summary and conclusion
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
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