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EC number: 257-409-4 | CAS number: 51773-49-0
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Toxicity to aquatic algae and cyanobacteria
Administrative data
- Endpoint:
- toxicity to aquatic algae and cyanobacteria
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- Nov - Dec 2001
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: According to OECD guideline under GLP
Cross-referenceopen allclose all
- Reason / purpose for cross-reference:
- reference to same study
- Reason / purpose for cross-reference:
- reference to other study
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 2 005
- Report date:
- 2005
Materials and methods
Test guideline
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 201 (Alga, Growth Inhibition Test)
- Deviations:
- no
- Principles of method if other than guideline:
- Not relevant
- GLP compliance:
- yes
Test material
- Reference substance name:
- [2R-[2α(E),3β]]-2-[2-(3,4-dihydro-6-methoxy-1(2H)-naphthylidene)ethyl]-2-ethyl-3-hydroxycyclopentan-1-one
- EC Number:
- 257-409-4
- EC Name:
- [2R-[2α(E),3β]]-2-[2-(3,4-dihydro-6-methoxy-1(2H)-naphthylidene)ethyl]-2-ethyl-3-hydroxycyclopentan-1-one
- Cas Number:
- 51773-49-0
- Molecular formula:
- C20H26O3
- IUPAC Name:
- 17 beta-Hydroxy-3-methoxy-18-methyl-8,14-seco-1,3,5(10),9(11)-estratetraen-14-one
- Test material form:
- solid: particulate/powder
- Remarks:
- migrated information: powder
- Details on test material:
- - Name of test material (as cited in study report): 13-Ethylsecol
- Analytical purity: 99.9%
- Lot/batch No.: 71004011
Constituent 1
Sampling and analysis
- Analytical monitoring:
- yes
Test solutions
- Vehicle:
- no
Test organisms
- Test organisms (species):
- Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Study design
- Test type:
- static
- Water media type:
- freshwater
- Limit test:
- no
- Total exposure duration:
- 72 h
Results and discussion
Effect concentrationsopen allclose all
- Duration:
- 72 h
- Dose descriptor:
- EC50
- Effect conc.:
- 11.4 mg/L
- Nominal / measured:
- meas. (arithm. mean)
- Conc. based on:
- test mat.
- Basis for effect:
- biomass
- Remarks on result:
- other: 11.0 - 11.8 mg/L
- Duration:
- 72 h
- Dose descriptor:
- EC50
- Effect conc.:
- 10.1 mg/L
- Nominal / measured:
- meas. (arithm. mean)
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: 7.8 - 12.1 mg/L
Any other information on results incl. tables
Table 1: Inhibition of biomass and the growth rate (%) of Desmodesmus subspicatus after 72 hours exposure to ZK 46072
Inhibition in percent | |||
Dilution of ZK46072 | Concentration of ZK 46072 (mg/L) | Biomass (integral) | Growth |
0 | 0,0 (control) | 0 | 0 |
1:100 | 0,2 | 6,2 | 4,5 |
1:50 | 0,4 | -3,4 | 0,5 |
1:25 | 0,9 | -29,5 | -3,7 |
1:10 | 2,2 | -13,3 | 0,6 |
1:5 | 4,4 | 0,4 | 5,0 |
Saturated solution | 17,7 | 89 | 86,8 |
Applicant's summary and conclusion
- Validity criteria fulfilled:
- yes
- Conclusions:
- 13-Ethylsecol had an inhibitory effect on the growth of Desmodesmus subspicatus. The EbC50 (biomass) was 11.4 mg/L [95% confidence limits: 11.0 -11.8], the ErC50 (growth rate) was 10.1 mg/L [95% confidence limits: 7.8-12.1] on the basis of measured concentrations.
Consequently, 13-Ethylsecol was considered to be toxic to the green algae Desmodesmus subspicatus, since the EC50 was approximately 10 mg/L. - Executive summary:
The purpose of this study was to determine the effects of the test compound 13 -Ethylsecol (ZK 46072) on the
growth of the green algae Desmodesmus subspicatus. 13 -Ethylsecol is an intermediate of the synthesis of gestodene and levonorgestrel. The study was conducted in agreement with the test guideline OECD no. 201.
The test substance was incubated in an aqueous solution including nutrients with an algae population of Desmodesmus subspicatus for a test duration of approximately 72 hours in an electronically controlled dosing and incubation apparatus.
The nutrient solution was made up of mainly nitrate, phosphates and some trace elements. For the preparation of the test solutions a suspension with a nominal loading of 100 mg/L the test substance in water was kept for approximately 30 min in an ultrasonic bath and stirred for approximately 24 hours. The highest concentration was a 1: 1.25 dilution obtained by adding nutrient solution and inoculum, the further concentrations were obtained by dilutions of 1: 100; 1:50; 1:25; 1: 10 and 1:5 with demineralized water, nutrient
solution and inoculum. Additionally, a control solution was prepared with demineralized water without test material.
The organic carbon concentration of the stock solution was analyzed with a TOC analyzer at the start of the incubation. The substance concentration was calculated on the basis of the molecular formula. It was 22.1 mg/L. The further test concentrations were extrapolated from the result of the TOC-analysis.
The algae were exposed to each concentration in triplicate. Six vessels were prepared for the control. The algae were incubated under standardized conditions (continous light, controlled temperature).
As a parameter for the growth of the algae population, the fluorescence of the algal cells was measured with a fluorescence-photometer.
The increase of biomass and the growth rate were calculated on the basis of the fluorescence.
The calculated biomass and growth rate of each concentration were compared to those of the controls, and the inhibition was calculated. 13-Ethylsecol was considered to be toxic to the green algae Desmodesmus subspicatus, since the EC50 was approximately 10 mg/L.
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