Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 203-565-3 | CAS number: 108-26-9
Toxicity to microorganisms
Administrative data
- Endpoint:
- toxicity to microorganisms
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Guideline study
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 1 989
- Report date:
- 1989
Materials and methods
Test guideline
- Qualifier:
- according to guideline
- Guideline:
- other: Bringmann-Kuehn
- GLP compliance:
- no
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
- Details on test material:
- - Name of test substance (as cited in study report): Methylpyrazolon
- Batch no.: 880010
Constituent 1
Sampling and analysis
- Analytical monitoring:
- no
Test solutions
- Vehicle:
- no
- Details on test solutions:
- - Concentration of stock solution: 12500 mg/L
- Preparation of replicates:
- Total volume: 10 ml
- 0.5 ml nutrient solution I
- 0.5 ml nutrient solution II
- 1 ml bacterial suspension with NaCL-solution
- 8 ml test item solution
Test organisms
- Test organisms (species):
- Pseudomonas putida
- Details on inoculum:
- - Strain: DSM 50026
- CULTURING OF PRE-CULTURE
- Medium: AK-Medium DIN 38412 part 8, draft
- Temperature: 24°C
- Culturing vessel: Erlenmeyer flask (300 ml volume)
- Culturing volume: 100 ml
- Duration of growth: 7 h +- 1 h
Study design
- Test type:
- static
- Water media type:
- freshwater
- Limit test:
- no
- Total exposure duration:
- 17 h
Test conditions
- Test temperature:
- 20°C
- Nominal and measured concentrations:
- - Concentrations tested (nominal): 39.06, 78.13, 156.25, 312.5, 625, 1250, 2500, 5000 and 10000 mg/L plus control
- Two additional neutralized concentrations have been tested: 1250 and 10000 mg/L
Results and discussion
Effect concentrationsopen allclose all
- Duration:
- 17 h
- Dose descriptor:
- EC10
- Effect conc.:
- 41.9 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth inhibition
- Duration:
- 17 h
- Dose descriptor:
- EC50
- Effect conc.:
- 72.8 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth inhibition
- Duration:
- 17 h
- Dose descriptor:
- other: EC90
- Effect conc.:
- 222.4 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth inhibition
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.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
