Registration Dossier
Registration Dossier
Data platform availability banner - registered substances factsheets
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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.
Diss Factsheets
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: 250-830-4 | CAS number: 31837-42-0
- 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
![](https://echa.europa.eu/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/print_ecotoxicological-information.png)
Toxicity to aquatic algae and cyanobacteria
Administrative data
Link to relevant study record(s)
- Endpoint:
- toxicity to aquatic algae and cyanobacteria
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 2011-10-28 to 2011-11-21
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: Study performed according to relevant guidelines and compliant to GLP
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 201 (Alga, Growth Inhibition Test)
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Remarks:
- according to German Chemikaliengesetzt and directive 88/320/EEC
- Analytical monitoring:
- yes
- Details on sampling:
- - Concentrations: The limit test item concentration and control were analytically verified via HPLC-DAD after 0 hours (test start) and 72 hours (test end).
- Sampling method: Samples at test start were taken from additional replicates without algae. After 72 hours samples were taken directly from pooled test replicates.
- Sample storage conditions before analysis: All samples were stored at 6 ± 2 C° until analysis, if necessary. - Vehicle:
- no
- Details on test solutions:
- PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution of 1 mg/L was freshly prepared with dilution water. The stock solution was stirred for 48 hours (1100 rpm) with a magnetic stirrer. Undissolved particles were removed by membrane filtration (membrane filter 0.45 µm, RC, MACHEREY-NAGEL). Centrifugation for 10 min at 10000 rpm was found to be insufficient.
- Eluate: Dilution water
- Differential loading: Saturated solution* corresponding to a nominal test item concentration of 1.00 mg/L, six replicates
- Controls: Six replicates without test item were tested under the same test conditions as the test replicates. - Test organisms (species):
- Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
- Details on test organisms:
- TEST ORGANISM
- Common name: Desmodesmus subspicatus Chodat
- Strain: SAG 86.81
- Source (laboratory, culture collection): SAG Pflanzenphysiologisches Institut der Universitaet Goettingen, Nikolausberger Weg 18, D-37073 Goettingen, Germany
- Age of inoculum (at test initiation): 4 days
- Method of cultivation: Fresh stocks were prepared every month on Z-Agar. Light intensity amounted to 35 - 70 µE x m-2 x s-1 for 24 h per day. - Test type:
- static
- Water media type:
- freshwater
- Limit test:
- yes
- Total exposure duration:
- 72 h
- Post exposure observation period:
- No
- Hardness:
- Dilution water: 0.24 mmol Ca+mg/L.
- Test temperature:
- min.: 21.5 max.: 22.5, mean value: 22.0
- pH:
- Nominal test item concentration pH-value
[mg/L] Start; 0 hours End; 72 hours
1.00 7.86 8.32
Control 7.92 8.72 - Dissolved oxygen:
- Not measured
- Salinity:
- Not measured, freshwater conditions
- Nominal and measured concentrations:
- Please refer to "Any other information on materials and methods"
- Details on test conditions:
- TEST SYSTEM
- Test vessel: 250 mL Erlenmeyer flasks
- Type (delete if not applicable): open, cotton wool plugs
- Material, size, headspace, fill volume: sterile 250 mL Erlenmeyer flasks, test volume 100 mL
- Aeration: Test containers were placed on a rotary shaker and oscillated at appr. 70 rpm
- Type of flow-through (e.g. peristaltic or proportional diluter): None
- Renewal rate of test solution (frequency/flow rate): One application at test start
- Initial cells density: Nominal: approximately 2 - 5 x 10^3 cells/mL, Actual: mean 4910 cells/mL
- Control end cells density: Mean 876660 cells/mL
- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 6
GROWTH MEDIUM
- Standard medium used: yes
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dilution water, composition acc. to the guideline
- Hardness: 0.24 mmol Ca+Mg/L
- pH-value: 8.1 +/- 0.2
- Culture medium: Nutrient Medium Z acc. to LÜTTGE et al. (1994)
OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: no
- Photoperiod: 24 h
- Light intensity and quality: 60 - 120 µE x m-2 x s-1, mean value: 69.2
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter] fluorimeter, Cell density and self fluorescence was measured daily via Chlorophyll-a- fluorescence, excitation at 436 nm, emission at 685 nm. Dilution water was used as background signal.
TEST CONCENTRATIONS
- Range finding study:
Results of the Range Finding Test (0-72 hours)
Nominal
test item concentration
[mg/L] Specific Growth Rate Inhibition [%] Yield Inhibition [%]
100 -1 -3
10 2 11
1 3 14
- Reference substance (positive control):
- yes
- Remarks:
- Potassium dichromate
- Duration:
- 72 h
- Dose descriptor:
- NOEC
- Effect conc.:
- 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to very poor solubility of test item, concentrations in water were below LOQ of analytical method (0.1 mg/L)
- Duration:
- 72 h
- Dose descriptor:
- EC10
- Effect conc.:
- > 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to very poor solubility of test item, concentrations in water were below LOQ of analytical method (0.1 mg/L)
- Details on results:
- - Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test):
- Unusual cell shape: No
- Colour differences: No
- Flocculation: No
- Adherence to test vessels: No
- Aggregation of algal cells: No
- Other: No
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No
- Effect concentrations exceeding solubility of substance in test medium: No - Results with reference substance (positive control):
- - Results with reference substance valid? Yes
EC50 Values of the Reference Item
based on nominal concentrations (mg/L), (0-72 hours)
Current Study Valid Range (average ± 3 x SD)
Rate-related inhibition
ErC50 0.488 0.699 ± 0.471
95 % confidence interval 0.466 – 0.512
Yield inhibition
EyC50 0.291 0.318 ± 0.147
95 % confidence interval 0.274 – 0.328 - Reported statistics and error estimates:
- NOEC/LOEC was determined by calculation of statistical
significance of growth rates and yield. As standard One Way Analysis of Variance (ANOVA) and DUNNETT’s Test were used for NOEC/LOEC calculations. When running a One Way Analysis of Variance a Normality test and an Equal Variance test were done first. The SHAPIRO-WILK-Test was used to test for normally distributed populations. The Levene median test was used for equal variance. P-values for both Normality and Equal Variance test were 0.05. The a-value (acceptable probability of incorrectly concluding that there is a difference) is a=0.05. - Validity criteria fulfilled:
- yes
- Conclusions:
- In this study no inhibition on growth of the freshwater green alga Desmodesmus subspicatus was found after 72 hours exposure to the test item. The NOEC for inhibition of specific growth rate and yield after 72 hours was 1.00 mg/L. All effect levels are given based on the nominal concentration of the test item, which has been analytically verified by HPLC-DAD.
- Executive summary:
The toxicity of the test item to the unicellular freshwater green alga Desmodesmus subspicatus was determined according to the principles of OECD 201. The aim of the study was to assess the effects on growth rate and yield over a period of 72 hours.
The study was conducted under static conditions with an initial cell density of 5 x 103 cells/mL. Based on a preliminary range finding the saturated solution* was tested. Six replicates were tested for the limit concentration and the control. Environmental conditions were determined to be within the acceptable limits.
The saturated solution* and the control were analysed by HPLC-DAD after 0 h (fresh media) and 72 h (old media).
The concentration (fresh media, 0 h) of the test item in the freshly prepared saturated solution* and in the old media (72 h) was< LOQ.
All effect values of the test item are given based on the nominal concentration. Table 1: NOEC, LOEC, EC - values of the test item (0-72 hours)
based on nominal concentration [mg/L]
Rate-related Inhibition
NOEC
1.00
LOEC
> 1.00
ErC10
> 1.00
ErC20
> 1.00
ErC50
> 1.00
Inhibition of Yield
NOEC
1.00
LOEC
> 1.00
EyC10
> 1.00
EyC20
> 1.00
EyC50
> 1.00
- Endpoint:
- toxicity to aquatic algae and cyanobacteria
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 2011-12-02 to 2011-12-09
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: Study performed according to relevant guidelines and compliant to GLP
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 201 (Alga, Growth Inhibition Test)
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Remarks:
- according to German Chemikaliengesetzt and directive 88/320/EEC
- Analytical monitoring:
- yes
- Details on sampling:
- - Concentrations: The limit test item concentration and control were analytically verified via HPLC-DAD after 0 hours (test start) and 72 hours (test end).
- Sampling method: Samples at test start were taken from additional replicates without algae. After 72 hours samples were taken directly from pooled test replicates.
- Sample storage conditions before analysis: All samples were stored at 6 ± 2 °C until sample preparation, if necessary. - Vehicle:
- no
- Details on test solutions:
- PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution of 1 mg/L was freshly prepared with dilution water.The stock solution was stirred for 48 hours (1100 rpm) with a magnetic stirrer. Undissolved particles were removed by membrane filtration (membrane filter 0.45 µm, RC, MACHEREY-NAGEL). Centrifugation for 10 min at 10000 rpm was found to be insufficient.
- Eluate: Dilution water
- Differential loading: None, saturated solution corresponding to a nominal test item concentration of 1.00 mg/L.
- Controls: Six replicates without test item were tested under the same test conditions as the test replicates. - Test organisms (species):
- Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
- Details on test organisms:
- TEST ORGANISM
- Common name: Desmodesmus subspicatus Chodat
- Strain: SAG 86.81
- Source (laboratory, culture collection): SAG Pflanzenphysiologisches Institut der Universitaet Goettingen, Nikolausberger Weg 18, D-37073 Goettingen, Germany
- Age of inoculum (at test initiation): 3 days
- Method of cultivation: Fresh stocks were prepared every month on Z-Agar. Light intensity amounted to 35 - 70 µE x m-2 x s-1 for 24 h per day. - Test type:
- static
- Water media type:
- freshwater
- Limit test:
- yes
- Total exposure duration:
- 72 h
- Post exposure observation period:
- No
- Hardness:
- Dilution water: 0.24 mmol Ca+mg/L.
- Test temperature:
- min.: 21.5 max.: 22.0, mean value: 21.8
- pH:
- pH-value
Start; 0 hours End; 72 hours
Saturated solution prepared
with 1 mg test item/L 7.85 8.51
Control 7.91 8.12 - Dissolved oxygen:
- Not measured
- Salinity:
- Not measured, freshwater conditions
- Nominal and measured concentrations:
- Please refer to "Any other information on materials and methods"
- Details on test conditions:
- TEST SYSTEM
- Test vessel: 250 mL Erlenmeyer flasks
- Type (delete if not applicable): open, cotton wool plugs
- Material, size, headspace, fill volume: sterile 250 mL Erlenmeyer flasks, test volume 100 mL
- Aeration: Test containers were placed on a rotary shaker and oscillated at appr. 70 rpm
- Type of flow-through (e.g. peristaltic or proportional diluter): None
- Renewal rate of test solution (frequency/flow rate): One application at test start
- Initial cells density: Nominal: approximately 2 - 5 x 103 cells/mL, Actual: mean 4910 cells/mL
- Control end cells density: 792206 cells/mL
- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 6
GROWTH MEDIUM
- Standard medium used: yes
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dilution water, composition acc. to the guideline
- Hardness: 0.24 mmol Ca+Mg/L
- pH-value: 8.1 +/- 0.2
- Culture medium: Nutrient Medium Z acc. to LÜTTGE et al. (1994)
OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: no
- Photoperiod: 24 h
- Light intensity and quality: 60 - 120 µE x m-2 x s-1, mean value: 69.2
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter] fluorimeter, Cell density and self fluorescence was measured daily via Chlorophyll-a- fluorescence, excitation at 436 nm, emission at 685 nm. Dilution water was used as background signal.
TEST CONCENTRATIONS
- Range finding study:
Results of the Range Finding Test (0-72 hours)
Nominal
test item concentration
[mg/L] Specific Growth Rate Inhibition [%] Yield Inhibition [%]
100 -4 -22
10 -2 -8
1 -1 -5
- Reference substance (positive control):
- yes
- Remarks:
- Potassium dichromate
- Duration:
- 72 h
- Dose descriptor:
- NOEC
- Effect conc.:
- 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to the very poor solubility of the test item, quantitative analytical determination was precluded (below LOQ)
- Duration:
- 72 h
- Dose descriptor:
- EC10
- Effect conc.:
- > 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to the very poor solubility of the test item, quantitative analytical determination was precluded (below LOQ)
- Duration:
- 72 h
- Dose descriptor:
- EC10
- Effect conc.:
- < 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- biomass
- Remarks on result:
- other: Due to the very poor solubility of the test item, quantitative analytical determination was precluded (below LOQ)
- Details on results:
- - Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test):
- Unusual cell shape: No
- Colour differences: No
- Flocculation: No
- Adherence to test vessels: No
- Aggregation of algal cells: No
- Other: No
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No
- Effect concentrations exceeding solubility of substance in test medium: No - Results with reference substance (positive control):
- - Results with reference substance valid? Yes
EC50 Values of the Reference Item
based on nominal concentrations (mg/L), (0-72 hours)
Current Study Valid Range (average ± 3 x SD)
Rate-related inhibition
ErC50 0.488 0.699 ± 0.471
95 % confidence interval 0.466 – 0.512
Yield inhibition
EyC50 0.291 0.318 ± 0.147
95 % confidence interval 0.274 – 0.328 - Reported statistics and error estimates:
- NOEC/LOEC was determined by calculation of statistical
significance of growth rates and yield. As standard One Way Analysis of Variance (ANOVA) was used for NOEC/LOEC calculations. When running a One Way Analysis of Variance a Normality test and an Equal Variance test were done first. The SHAPIRO-WILK-Test was used to test for normally distributed populations. The Levene median test was used for equal variance. P-values for both Normality and Equal Variance test were 0.05. The a-value (acceptable probability of incorrectly concluding that there is a difference) is a=0.05. - Validity criteria fulfilled:
- yes
- Conclusions:
- In this study no inhibition on growth of the freshwater green alga Desmodesmus subspicatus was found after 72 hours exposure to the test item. The NOEC for inhibition of specific growth rate and yield after 72 hours was 1.00 mg/L. All effect levels are given based on the nominal concentration of the test item.
- Executive summary:
The toxicity of the test item to the unicellular freshwater green alga Desmodesmus subspicatus was determined according to the principles of OECD 201 at Dr.U.Noack-Laboratorienin 31157 Sarstedt, Germany from 2011-12-02 to 2011-12-09, with the definitive exposure phase from 2011-12-06 to 2011-12-09. The aim of the study was to assess the effects on growth rate and yield over a period of 72 hours.
The study was conducted under static conditions with an initial cell density of 5 x 103 cells/mL. Based on a preliminary range finding the saturated solution* was tested. Six replicates were tested for the limit concentration and the control. Environmental conditions were determined to be within the acceptable limits.
The saturated solution* and the control were analysed by HPLC-DAD after 0 h (fresh media) and 72 h (old media).
The concentration (fresh media, 0 h) of the test item in the freshly prepared saturated solution* and in the old media (72 h) was
, therefore all effect values of the test item are given based on the saturated solution prepared with 1 mg/L. Table 1: NOEC, LOEC, EC - values of the test item (0-72 hours)
based on the saturated solution prepared with 1 mg test item/L
Rate-related Inhibition
NOEC
1.00
LOEC
> 1.00
ErC10
> 1.00
ErC20
> 1.00
ErC50
> 1.00
Inhibition of Yield
NOEC
1.00
LOEC
> 1.00
EyC10
1.00
EyC20
> 1.00
EyC50
> 1.00
- Endpoint:
- toxicity to aquatic algae and cyanobacteria
- Type of information:
- read-across from supporting substance (structural analogue or surrogate)
- Adequacy of study:
- key study
- Study period:
- 2011-10-28 to 2011-11-21
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: Study performed according to relevant guidelines and compliant to GLP
- Justification for type of information:
- see Rationale and Justification for the Analogue Read-Across Approach used for the Registration of Acetolone Pigments – Nanoforms and Bulk Forms (Chapter 13)
- Reason / purpose for cross-reference:
- read-across source
- Reason / purpose for cross-reference:
- read-across source
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 201 (Alga, Growth Inhibition Test)
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Remarks:
- according to German Chemikaliengesetzt and directive 88/320/EEC
- Analytical monitoring:
- yes
- Details on sampling:
- - Concentrations: The limit test item concentration and control were analytically verified via HPLC-DAD after 0 hours (test start) and 72 hours (test end).
- Sampling method: Samples at test start were taken from additional replicates without algae. After 72 hours samples were taken directly from pooled test replicates.
- Sample storage conditions before analysis: All samples were stored at 6 ± 2 C° until analysis, if necessary. - Vehicle:
- no
- Details on test solutions:
- PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution of 1 mg/L was freshly prepared with dilution water. The stock solution was stirred for 48 hours (1100 rpm) with a magnetic stirrer. Undissolved particles were removed by membrane filtration (membrane filter 0.45 µm, RC, MACHEREY-NAGEL). Centrifugation for 10 min at 10000 rpm was found to be insufficient.
- Eluate: Dilution water
- Differential loading: Saturated solution* corresponding to a nominal test item concentration of 1.00 mg/L, six replicates
- Controls: Six replicates without test item were tested under the same test conditions as the test replicates. - Test organisms (species):
- Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
- Details on test organisms:
- TEST ORGANISM
- Common name: Desmodesmus subspicatus Chodat
- Strain: SAG 86.81
- Source (laboratory, culture collection): SAG Pflanzenphysiologisches Institut der Universitaet Goettingen, Nikolausberger Weg 18, D-37073 Goettingen, Germany
- Age of inoculum (at test initiation): 4 days
- Method of cultivation: Fresh stocks were prepared every month on Z-Agar. Light intensity amounted to 35 - 70 µE x m-2 x s-1 for 24 h per day. - Test type:
- static
- Water media type:
- freshwater
- Limit test:
- yes
- Total exposure duration:
- 72 h
- Post exposure observation period:
- No
- Hardness:
- Dilution water: 0.24 mmol Ca+mg/L.
- Test temperature:
- min.: 21.5 max.: 22.5, mean value: 22.0
- pH:
- Nominal test item concentration pH-value
[mg/L] Start; 0 hours End; 72 hours
1.00 7.86 8.32
Control 7.92 8.72 - Dissolved oxygen:
- Not measured
- Salinity:
- Not measured, freshwater conditions
- Nominal and measured concentrations:
- Please refer to "Any other information on materials and methods"
- Details on test conditions:
- TEST SYSTEM
- Test vessel: 250 mL Erlenmeyer flasks
- Type (delete if not applicable): open, cotton wool plugs
- Material, size, headspace, fill volume: sterile 250 mL Erlenmeyer flasks, test volume 100 mL
- Aeration: Test containers were placed on a rotary shaker and oscillated at appr. 70 rpm
- Type of flow-through (e.g. peristaltic or proportional diluter): None
- Renewal rate of test solution (frequency/flow rate): One application at test start
- Initial cells density: Nominal: approximately 2 - 5 x 10^3 cells/mL, Actual: mean 4910 cells/mL
- Control end cells density: Mean 876660 cells/mL
- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 6
GROWTH MEDIUM
- Standard medium used: yes
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dilution water, composition acc. to the guideline
- Hardness: 0.24 mmol Ca+Mg/L
- pH-value: 8.1 +/- 0.2
- Culture medium: Nutrient Medium Z acc. to LÜTTGE et al. (1994)
OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: no
- Photoperiod: 24 h
- Light intensity and quality: 60 - 120 µE x m-2 x s-1, mean value: 69.2
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter] fluorimeter, Cell density and self fluorescence was measured daily via Chlorophyll-a- fluorescence, excitation at 436 nm, emission at 685 nm. Dilution water was used as background signal.
TEST CONCENTRATIONS
- Range finding study:
Results of the Range Finding Test (0-72 hours)
Nominal
test item concentration
[mg/L] Specific Growth Rate Inhibition [%] Yield Inhibition [%]
100 -1 -3
10 2 11
1 3 14
- Reference substance (positive control):
- yes
- Remarks:
- Potassium dichromate
- Duration:
- 72 h
- Dose descriptor:
- NOEC
- Effect conc.:
- 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to very poor solubility of test item, concentrations in water were below LOQ of analytical method (0.1 mg/L)
- Duration:
- 72 h
- Dose descriptor:
- EC10
- Effect conc.:
- > 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to very poor solubility of test item, concentrations in water were below LOQ of analytical method (0.1 mg/L)
- Details on results:
- - Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test):
- Unusual cell shape: No
- Colour differences: No
- Flocculation: No
- Adherence to test vessels: No
- Aggregation of algal cells: No
- Other: No
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No
- Effect concentrations exceeding solubility of substance in test medium: No - Results with reference substance (positive control):
- - Results with reference substance valid? Yes
EC50 Values of the Reference Item
based on nominal concentrations (mg/L), (0-72 hours)
Current Study Valid Range (average ± 3 x SD)
Rate-related inhibition
ErC50 0.488 0.699 ± 0.471
95 % confidence interval 0.466 – 0.512
Yield inhibition
EyC50 0.291 0.318 ± 0.147
95 % confidence interval 0.274 – 0.328 - Reported statistics and error estimates:
- NOEC/LOEC was determined by calculation of statistical
significance of growth rates and yield. As standard One Way Analysis of Variance (ANOVA) and DUNNETT’s Test were used for NOEC/LOEC calculations. When running a One Way Analysis of Variance a Normality test and an Equal Variance test were done first. The SHAPIRO-WILK-Test was used to test for normally distributed populations. The Levene median test was used for equal variance. P-values for both Normality and Equal Variance test were 0.05. The a-value (acceptable probability of incorrectly concluding that there is a difference) is a=0.05. - Validity criteria fulfilled:
- yes
- Conclusions:
- In this study no inhibition on growth of the freshwater green alga Desmodesmus subspicatus was found after 72 hours exposure to the test item. The NOEC for inhibition of specific growth rate and yield after 72 hours was 1.00 mg/L. All effect levels are given based on the nominal concentration of the test item, which has been analytically verified by HPLC-DAD.
- Executive summary:
The toxicity of the test item to the unicellular freshwater green alga Desmodesmus subspicatus was determined according to the principles of OECD 201. The aim of the study was to assess the effects on growth rate and yield over a period of 72 hours.
The study was conducted under static conditions with an initial cell density of 5 x 103 cells/mL. Based on a preliminary range finding the saturated solution* was tested. Six replicates were tested for the limit concentration and the control. Environmental conditions were determined to be within the acceptable limits.
The saturated solution* and the control were analysed by HPLC-DAD after 0 h (fresh media) and 72 h (old media).
The concentration (fresh media, 0 h) of the test item in the freshly prepared saturated solution* and in the old media (72 h) was< LOQ.
All effect values of the test item are given based on the nominal concentration. Table 1: NOEC, LOEC, EC - values of the test item (0-72 hours)
based on nominal concentration [mg/L]
Rate-related Inhibition
NOEC
1.00
LOEC
> 1.00
ErC10
> 1.00
ErC20
> 1.00
ErC50
> 1.00
Inhibition of Yield
NOEC
1.00
LOEC
> 1.00
EyC10
> 1.00
EyC20
> 1.00
EyC50
> 1.00
- Endpoint:
- toxicity to aquatic algae and cyanobacteria
- Type of information:
- read-across from supporting substance (structural analogue or surrogate)
- Adequacy of study:
- key study
- Study period:
- 2011-12-02 to 2011-12-09
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: Study performed according to relevant guidelines and compliant to GLP
- Justification for type of information:
- see Rationale and Justification for the Analogue Read-Across Approach used for the Registration of Acetolone Pigments – Nanoforms and Bulk Forms (Chapter 13)
- Reason / purpose for cross-reference:
- read-across source
- Reason / purpose for cross-reference:
- read-across source
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 201 (Alga, Growth Inhibition Test)
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Remarks:
- according to German Chemikaliengesetzt and directive 88/320/EEC
- Analytical monitoring:
- yes
- Details on sampling:
- - Concentrations: The limit test item concentration and control were analytically verified via HPLC-DAD after 0 hours (test start) and 72 hours (test end).
- Sampling method: Samples at test start were taken from additional replicates without algae. After 72 hours samples were taken directly from pooled test replicates.
- Sample storage conditions before analysis: All samples were stored at 6 ± 2 °C until sample preparation, if necessary. - Vehicle:
- no
- Details on test solutions:
- PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution of 1 mg/L was freshly prepared with dilution water.The stock solution was stirred for 48 hours (1100 rpm) with a magnetic stirrer. Undissolved particles were removed by membrane filtration (membrane filter 0.45 µm, RC, MACHEREY-NAGEL). Centrifugation for 10 min at 10000 rpm was found to be insufficient.
- Eluate: Dilution water
- Differential loading: None, saturated solution corresponding to a nominal test item concentration of 1.00 mg/L.
- Controls: Six replicates without test item were tested under the same test conditions as the test replicates. - Test organisms (species):
- Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
- Details on test organisms:
- TEST ORGANISM
- Common name: Desmodesmus subspicatus Chodat
- Strain: SAG 86.81
- Source (laboratory, culture collection): SAG Pflanzenphysiologisches Institut der Universitaet Goettingen, Nikolausberger Weg 18, D-37073 Goettingen, Germany
- Age of inoculum (at test initiation): 3 days
- Method of cultivation: Fresh stocks were prepared every month on Z-Agar. Light intensity amounted to 35 - 70 µE x m-2 x s-1 for 24 h per day. - Test type:
- static
- Water media type:
- freshwater
- Limit test:
- yes
- Total exposure duration:
- 72 h
- Post exposure observation period:
- No
- Hardness:
- Dilution water: 0.24 mmol Ca+mg/L.
- Test temperature:
- min.: 21.5 max.: 22.0, mean value: 21.8
- pH:
- pH-value
Start; 0 hours End; 72 hours
Saturated solution prepared
with 1 mg test item/L 7.85 8.51
Control 7.91 8.12 - Dissolved oxygen:
- Not measured
- Salinity:
- Not measured, freshwater conditions
- Nominal and measured concentrations:
- Please refer to "Any other information on materials and methods"
- Details on test conditions:
- TEST SYSTEM
- Test vessel: 250 mL Erlenmeyer flasks
- Type (delete if not applicable): open, cotton wool plugs
- Material, size, headspace, fill volume: sterile 250 mL Erlenmeyer flasks, test volume 100 mL
- Aeration: Test containers were placed on a rotary shaker and oscillated at appr. 70 rpm
- Type of flow-through (e.g. peristaltic or proportional diluter): None
- Renewal rate of test solution (frequency/flow rate): One application at test start
- Initial cells density: Nominal: approximately 2 - 5 x 103 cells/mL, Actual: mean 4910 cells/mL
- Control end cells density: 792206 cells/mL
- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 6
GROWTH MEDIUM
- Standard medium used: yes
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dilution water, composition acc. to the guideline
- Hardness: 0.24 mmol Ca+Mg/L
- pH-value: 8.1 +/- 0.2
- Culture medium: Nutrient Medium Z acc. to LÜTTGE et al. (1994)
OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: no
- Photoperiod: 24 h
- Light intensity and quality: 60 - 120 µE x m-2 x s-1, mean value: 69.2
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter] fluorimeter, Cell density and self fluorescence was measured daily via Chlorophyll-a- fluorescence, excitation at 436 nm, emission at 685 nm. Dilution water was used as background signal.
TEST CONCENTRATIONS
- Range finding study:
Results of the Range Finding Test (0-72 hours)
Nominal
test item concentration
[mg/L] Specific Growth Rate Inhibition [%] Yield Inhibition [%]
100 -4 -22
10 -2 -8
1 -1 -5
- Reference substance (positive control):
- yes
- Remarks:
- Potassium dichromate
- Duration:
- 72 h
- Dose descriptor:
- NOEC
- Effect conc.:
- 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to the very poor solubility of the test item, quantitative analytical determination was precluded (below LOQ)
- Duration:
- 72 h
- Dose descriptor:
- EC10
- Effect conc.:
- > 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to the very poor solubility of the test item, quantitative analytical determination was precluded (below LOQ)
- Duration:
- 72 h
- Dose descriptor:
- EC10
- Effect conc.:
- < 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- biomass
- Remarks on result:
- other: Due to the very poor solubility of the test item, quantitative analytical determination was precluded (below LOQ)
- Details on results:
- - Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test):
- Unusual cell shape: No
- Colour differences: No
- Flocculation: No
- Adherence to test vessels: No
- Aggregation of algal cells: No
- Other: No
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No
- Effect concentrations exceeding solubility of substance in test medium: No - Results with reference substance (positive control):
- - Results with reference substance valid? Yes
EC50 Values of the Reference Item
based on nominal concentrations (mg/L), (0-72 hours)
Current Study Valid Range (average ± 3 x SD)
Rate-related inhibition
ErC50 0.488 0.699 ± 0.471
95 % confidence interval 0.466 – 0.512
Yield inhibition
EyC50 0.291 0.318 ± 0.147
95 % confidence interval 0.274 – 0.328 - Reported statistics and error estimates:
- NOEC/LOEC was determined by calculation of statistical
significance of growth rates and yield. As standard One Way Analysis of Variance (ANOVA) was used for NOEC/LOEC calculations. When running a One Way Analysis of Variance a Normality test and an Equal Variance test were done first. The SHAPIRO-WILK-Test was used to test for normally distributed populations. The Levene median test was used for equal variance. P-values for both Normality and Equal Variance test were 0.05. The a-value (acceptable probability of incorrectly concluding that there is a difference) is a=0.05. - Validity criteria fulfilled:
- yes
- Conclusions:
- In this study no inhibition on growth of the freshwater green alga Desmodesmus subspicatus was found after 72 hours exposure to the test item. The NOEC for inhibition of specific growth rate and yield after 72 hours was 1.00 mg/L. All effect levels are given based on the nominal concentration of the test item.
- Executive summary:
The toxicity of the test item to the unicellular freshwater green alga Desmodesmus subspicatus was determined according to the principles of OECD 201 at Dr.U.Noack-Laboratorienin 31157 Sarstedt, Germany from 2011-12-02 to 2011-12-09, with the definitive exposure phase from 2011-12-06 to 2011-12-09. The aim of the study was to assess the effects on growth rate and yield over a period of 72 hours.
The study was conducted under static conditions with an initial cell density of 5 x 103 cells/mL. Based on a preliminary range finding the saturated solution* was tested. Six replicates were tested for the limit concentration and the control. Environmental conditions were determined to be within the acceptable limits.
The saturated solution* and the control were analysed by HPLC-DAD after 0 h (fresh media) and 72 h (old media).
The concentration (fresh media, 0 h) of the test item in the freshly prepared saturated solution* and in the old media (72 h) was
, therefore all effect values of the test item are given based on the saturated solution prepared with 1 mg/L. Table 1: NOEC, LOEC, EC - values of the test item (0-72 hours)
based on the saturated solution prepared with 1 mg test item/L
Rate-related Inhibition
NOEC
1.00
LOEC
> 1.00
ErC10
> 1.00
ErC20
> 1.00
ErC50
> 1.00
Inhibition of Yield
NOEC
1.00
LOEC
> 1.00
EyC10
1.00
EyC20
> 1.00
EyC50
> 1.00
- Endpoint:
- toxicity to aquatic algae and cyanobacteria
- Type of information:
- read-across from supporting substance (structural analogue or surrogate)
- Adequacy of study:
- key study
- Study period:
- 2011-10-28 to 2011-11-21
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: Study performed according to relevant guidelines and compliant to GLP
- Justification for type of information:
- see Rationale and Justification for the Analogue Read-Across Approach used for the Registration of Acetolone Pigments – Nanoforms and Bulk Forms (Chapter 13)
- Reason / purpose for cross-reference:
- read-across source
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 201 (Alga, Growth Inhibition Test)
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Remarks:
- according to German Chemikaliengesetzt and directive 88/320/EEC
- Analytical monitoring:
- yes
- Details on sampling:
- - Concentrations: The limit test item concentration and control were analytically verified via HPLC-DAD after 0 hours (test start) and 72 hours (test end).
- Sampling method: Samples at test start were taken from additional replicates without algae. After 72 hours samples were taken directly from pooled test replicates.
- Sample storage conditions before analysis: All samples were stored at 6 ± 2 C° until analysis, if necessary. - Vehicle:
- no
- Details on test solutions:
- PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution of 1 mg/L was freshly prepared with dilution water. The stock solution was stirred for 48 hours (1100 rpm) with a magnetic stirrer. Undissolved particles were removed by membrane filtration (membrane filter 0.45 µm, RC, MACHEREY-NAGEL). Centrifugation for 10 min at 10000 rpm was found to be insufficient.
- Eluate: Dilution water
- Differential loading: Saturated solution* corresponding to a nominal test item concentration of 1.00 mg/L, six replicates
- Controls: Six replicates without test item were tested under the same test conditions as the test replicates. - Test organisms (species):
- Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
- Details on test organisms:
- TEST ORGANISM
- Common name: Desmodesmus subspicatus Chodat
- Strain: SAG 86.81
- Source (laboratory, culture collection): SAG Pflanzenphysiologisches Institut der Universitaet Goettingen, Nikolausberger Weg 18, D-37073 Goettingen, Germany
- Age of inoculum (at test initiation): 4 days
- Method of cultivation: Fresh stocks were prepared every month on Z-Agar. Light intensity amounted to 35 - 70 µE x m-2 x s-1 for 24 h per day. - Test type:
- static
- Water media type:
- freshwater
- Limit test:
- yes
- Total exposure duration:
- 72 h
- Post exposure observation period:
- No
- Hardness:
- Dilution water: 0.24 mmol Ca+mg/L.
- Test temperature:
- min.: 21.5 max.: 22.5, mean value: 22.0
- pH:
- Nominal test item concentration pH-value
[mg/L] Start; 0 hours End; 72 hours
1.00 7.86 8.32
Control 7.92 8.72 - Dissolved oxygen:
- Not measured
- Salinity:
- Not measured, freshwater conditions
- Nominal and measured concentrations:
- Please refer to "Any other information on materials and methods"
- Details on test conditions:
- TEST SYSTEM
- Test vessel: 250 mL Erlenmeyer flasks
- Type (delete if not applicable): open, cotton wool plugs
- Material, size, headspace, fill volume: sterile 250 mL Erlenmeyer flasks, test volume 100 mL
- Aeration: Test containers were placed on a rotary shaker and oscillated at appr. 70 rpm
- Type of flow-through (e.g. peristaltic or proportional diluter): None
- Renewal rate of test solution (frequency/flow rate): One application at test start
- Initial cells density: Nominal: approximately 2 - 5 x 10^3 cells/mL, Actual: mean 4910 cells/mL
- Control end cells density: Mean 876660 cells/mL
- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 6
GROWTH MEDIUM
- Standard medium used: yes
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dilution water, composition acc. to the guideline
- Hardness: 0.24 mmol Ca+Mg/L
- pH-value: 8.1 +/- 0.2
- Culture medium: Nutrient Medium Z acc. to LÜTTGE et al. (1994)
OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: no
- Photoperiod: 24 h
- Light intensity and quality: 60 - 120 µE x m-2 x s-1, mean value: 69.2
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter] fluorimeter, Cell density and self fluorescence was measured daily via Chlorophyll-a- fluorescence, excitation at 436 nm, emission at 685 nm. Dilution water was used as background signal.
TEST CONCENTRATIONS
- Range finding study:
Results of the Range Finding Test (0-72 hours)
Nominal
test item concentration
[mg/L] Specific Growth Rate Inhibition [%] Yield Inhibition [%]
100 -1 -3
10 2 11
1 3 14
- Reference substance (positive control):
- yes
- Remarks:
- Potassium dichromate
- Duration:
- 72 h
- Dose descriptor:
- NOEC
- Effect conc.:
- 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to very poor solubility of test item, concentrations in water were below LOQ of analytical method (0.1 mg/L)
- Duration:
- 72 h
- Dose descriptor:
- EC10
- Effect conc.:
- > 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to very poor solubility of test item, concentrations in water were below LOQ of analytical method (0.1 mg/L)
- Details on results:
- - Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test):
- Unusual cell shape: No
- Colour differences: No
- Flocculation: No
- Adherence to test vessels: No
- Aggregation of algal cells: No
- Other: No
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No
- Effect concentrations exceeding solubility of substance in test medium: No - Results with reference substance (positive control):
- - Results with reference substance valid? Yes
EC50 Values of the Reference Item
based on nominal concentrations (mg/L), (0-72 hours)
Current Study Valid Range (average ± 3 x SD)
Rate-related inhibition
ErC50 0.488 0.699 ± 0.471
95 % confidence interval 0.466 – 0.512
Yield inhibition
EyC50 0.291 0.318 ± 0.147
95 % confidence interval 0.274 – 0.328 - Reported statistics and error estimates:
- NOEC/LOEC was determined by calculation of statistical
significance of growth rates and yield. As standard One Way Analysis of Variance (ANOVA) and DUNNETT’s Test were used for NOEC/LOEC calculations. When running a One Way Analysis of Variance a Normality test and an Equal Variance test were done first. The SHAPIRO-WILK-Test was used to test for normally distributed populations. The Levene median test was used for equal variance. P-values for both Normality and Equal Variance test were 0.05. The a-value (acceptable probability of incorrectly concluding that there is a difference) is a=0.05. - Validity criteria fulfilled:
- yes
- Conclusions:
- In this study no inhibition on growth of the freshwater green alga Desmodesmus subspicatus was found after 72 hours exposure to the test item. The NOEC for inhibition of specific growth rate and yield after 72 hours was 1.00 mg/L. All effect levels are given based on the nominal concentration of the test item, which has been analytically verified by HPLC-DAD.
- Executive summary:
The toxicity of the test item to the unicellular freshwater green alga Desmodesmus subspicatus was determined according to the principles of OECD 201. The aim of the study was to assess the effects on growth rate and yield over a period of 72 hours.
The study was conducted under static conditions with an initial cell density of 5 x 103 cells/mL. Based on a preliminary range finding the saturated solution* was tested. Six replicates were tested for the limit concentration and the control. Environmental conditions were determined to be within the acceptable limits.
The saturated solution* and the control were analysed by HPLC-DAD after 0 h (fresh media) and 72 h (old media).
The concentration (fresh media, 0 h) of the test item in the freshly prepared saturated solution* and in the old media (72 h) was< LOQ.
All effect values of the test item are given based on the nominal concentration. Table 1: NOEC, LOEC, EC - values of the test item (0-72 hours)
based on nominal concentration [mg/L]
Rate-related Inhibition
NOEC
1.00
LOEC
> 1.00
ErC10
> 1.00
ErC20
> 1.00
ErC50
> 1.00
Inhibition of Yield
NOEC
1.00
LOEC
> 1.00
EyC10
> 1.00
EyC20
> 1.00
EyC50
> 1.00
- Endpoint:
- toxicity to aquatic algae and cyanobacteria
- Type of information:
- read-across from supporting substance (structural analogue or surrogate)
- Adequacy of study:
- key study
- Study period:
- 2011-12-02 to 2011-12-09
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: Study performed according to relevant guidelines and compliant to GLP
- Justification for type of information:
- see Rationale and Justification for the Analogue Read-Across Approach used for the Registration of Acetolone Pigments – Nanoforms and Bulk Forms (Chapter 13)
- Reason / purpose for cross-reference:
- read-across source
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 201 (Alga, Growth Inhibition Test)
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Remarks:
- according to German Chemikaliengesetzt and directive 88/320/EEC
- Analytical monitoring:
- yes
- Details on sampling:
- - Concentrations: The limit test item concentration and control were analytically verified via HPLC-DAD after 0 hours (test start) and 72 hours (test end).
- Sampling method: Samples at test start were taken from additional replicates without algae. After 72 hours samples were taken directly from pooled test replicates.
- Sample storage conditions before analysis: All samples were stored at 6 ± 2 °C until sample preparation, if necessary. - Vehicle:
- no
- Details on test solutions:
- PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution of 1 mg/L was freshly prepared with dilution water.The stock solution was stirred for 48 hours (1100 rpm) with a magnetic stirrer. Undissolved particles were removed by membrane filtration (membrane filter 0.45 µm, RC, MACHEREY-NAGEL). Centrifugation for 10 min at 10000 rpm was found to be insufficient.
- Eluate: Dilution water
- Differential loading: None, saturated solution corresponding to a nominal test item concentration of 1.00 mg/L.
- Controls: Six replicates without test item were tested under the same test conditions as the test replicates. - Test organisms (species):
- Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
- Details on test organisms:
- TEST ORGANISM
- Common name: Desmodesmus subspicatus Chodat
- Strain: SAG 86.81
- Source (laboratory, culture collection): SAG Pflanzenphysiologisches Institut der Universitaet Goettingen, Nikolausberger Weg 18, D-37073 Goettingen, Germany
- Age of inoculum (at test initiation): 3 days
- Method of cultivation: Fresh stocks were prepared every month on Z-Agar. Light intensity amounted to 35 - 70 µE x m-2 x s-1 for 24 h per day. - Test type:
- static
- Water media type:
- freshwater
- Limit test:
- yes
- Total exposure duration:
- 72 h
- Post exposure observation period:
- No
- Hardness:
- Dilution water: 0.24 mmol Ca+mg/L.
- Test temperature:
- min.: 21.5 max.: 22.0, mean value: 21.8
- pH:
- pH-value
Start; 0 hours End; 72 hours
Saturated solution prepared
with 1 mg test item/L 7.85 8.51
Control 7.91 8.12 - Dissolved oxygen:
- Not measured
- Salinity:
- Not measured, freshwater conditions
- Nominal and measured concentrations:
- Please refer to "Any other information on materials and methods"
- Details on test conditions:
- TEST SYSTEM
- Test vessel: 250 mL Erlenmeyer flasks
- Type (delete if not applicable): open, cotton wool plugs
- Material, size, headspace, fill volume: sterile 250 mL Erlenmeyer flasks, test volume 100 mL
- Aeration: Test containers were placed on a rotary shaker and oscillated at appr. 70 rpm
- Type of flow-through (e.g. peristaltic or proportional diluter): None
- Renewal rate of test solution (frequency/flow rate): One application at test start
- Initial cells density: Nominal: approximately 2 - 5 x 103 cells/mL, Actual: mean 4910 cells/mL
- Control end cells density: 792206 cells/mL
- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 6
GROWTH MEDIUM
- Standard medium used: yes
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dilution water, composition acc. to the guideline
- Hardness: 0.24 mmol Ca+Mg/L
- pH-value: 8.1 +/- 0.2
- Culture medium: Nutrient Medium Z acc. to LÜTTGE et al. (1994)
OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: no
- Photoperiod: 24 h
- Light intensity and quality: 60 - 120 µE x m-2 x s-1, mean value: 69.2
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter] fluorimeter, Cell density and self fluorescence was measured daily via Chlorophyll-a- fluorescence, excitation at 436 nm, emission at 685 nm. Dilution water was used as background signal.
TEST CONCENTRATIONS
- Range finding study:
Results of the Range Finding Test (0-72 hours)
Nominal
test item concentration
[mg/L] Specific Growth Rate Inhibition [%] Yield Inhibition [%]
100 -4 -22
10 -2 -8
1 -1 -5
- Reference substance (positive control):
- yes
- Remarks:
- Potassium dichromate
- Duration:
- 72 h
- Dose descriptor:
- NOEC
- Effect conc.:
- 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to the very poor solubility of the test item, quantitative analytical determination was precluded (below LOQ)
- Duration:
- 72 h
- Dose descriptor:
- EC10
- Effect conc.:
- > 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- growth rate
- Remarks on result:
- other: Due to the very poor solubility of the test item, quantitative analytical determination was precluded (below LOQ)
- Duration:
- 72 h
- Dose descriptor:
- EC10
- Effect conc.:
- < 1 mg/L
- Nominal / measured:
- nominal
- Conc. based on:
- test mat.
- Basis for effect:
- biomass
- Remarks on result:
- other: Due to the very poor solubility of the test item, quantitative analytical determination was precluded (below LOQ)
- Details on results:
- - Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test):
- Unusual cell shape: No
- Colour differences: No
- Flocculation: No
- Adherence to test vessels: No
- Aggregation of algal cells: No
- Other: No
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No
- Effect concentrations exceeding solubility of substance in test medium: No - Results with reference substance (positive control):
- - Results with reference substance valid? Yes
EC50 Values of the Reference Item
based on nominal concentrations (mg/L), (0-72 hours)
Current Study Valid Range (average ± 3 x SD)
Rate-related inhibition
ErC50 0.488 0.699 ± 0.471
95 % confidence interval 0.466 – 0.512
Yield inhibition
EyC50 0.291 0.318 ± 0.147
95 % confidence interval 0.274 – 0.328 - Reported statistics and error estimates:
- NOEC/LOEC was determined by calculation of statistical
significance of growth rates and yield. As standard One Way Analysis of Variance (ANOVA) was used for NOEC/LOEC calculations. When running a One Way Analysis of Variance a Normality test and an Equal Variance test were done first. The SHAPIRO-WILK-Test was used to test for normally distributed populations. The Levene median test was used for equal variance. P-values for both Normality and Equal Variance test were 0.05. The a-value (acceptable probability of incorrectly concluding that there is a difference) is a=0.05. - Validity criteria fulfilled:
- yes
- Conclusions:
- In this study no inhibition on growth of the freshwater green alga Desmodesmus subspicatus was found after 72 hours exposure to the test item. The NOEC for inhibition of specific growth rate and yield after 72 hours was 1.00 mg/L. All effect levels are given based on the nominal concentration of the test item.
- Executive summary:
The toxicity of the test item to the unicellular freshwater green alga Desmodesmus subspicatus was determined according to the principles of OECD 201 at Dr.U.Noack-Laboratorienin 31157 Sarstedt, Germany from 2011-12-02 to 2011-12-09, with the definitive exposure phase from 2011-12-06 to 2011-12-09. The aim of the study was to assess the effects on growth rate and yield over a period of 72 hours.
The study was conducted under static conditions with an initial cell density of 5 x 103 cells/mL. Based on a preliminary range finding the saturated solution* was tested. Six replicates were tested for the limit concentration and the control. Environmental conditions were determined to be within the acceptable limits.
The saturated solution* and the control were analysed by HPLC-DAD after 0 h (fresh media) and 72 h (old media).
The concentration (fresh media, 0 h) of the test item in the freshly prepared saturated solution* and in the old media (72 h) was
, therefore all effect values of the test item are given based on the saturated solution prepared with 1 mg/L. Table 1: NOEC, LOEC, EC - values of the test item (0-72 hours)
based on the saturated solution prepared with 1 mg test item/L
Rate-related Inhibition
NOEC
1.00
LOEC
> 1.00
ErC10
> 1.00
ErC20
> 1.00
ErC50
> 1.00
Inhibition of Yield
NOEC
1.00
LOEC
> 1.00
EyC10
1.00
EyC20
> 1.00
EyC50
> 1.00
Referenceopen allclose all
NOEC, LOEC, EC - values of the test item (0-72 hours)
based on nominal concentration [mg/L]
Rate-related Inhibition |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
ErC10 |
> 1.00 |
ErC20 |
> 1.00 |
ErC50 |
> 1.00 |
Inhibition of Yield |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
EyC10 |
> 1.00 |
EyC20 |
> 1.00 |
EyC50 |
> 1.00 |
Cell Densities
|
Nominal |
Replicate |
Cell density [cells/mL] |
||||||
[mg/L] |
No. |
0 hours |
24 hours |
48 hours |
72 hours |
|
|||
1.00 |
1 |
4910 |
24018 |
175395 |
899328 |
|
|||
2 |
4910 |
24065 |
170213 |
829699 |
|
||||
3 |
4910 |
28137 |
174989 |
949731 |
|
||||
4 |
4910 |
22779 |
156551 |
815888 |
|
||||
5 |
4910 |
27027 |
172230 |
820796 |
|
||||
6 |
4910 |
26983 |
145096 |
824520 |
|
||||
Mean |
4910 |
25502 |
165746 |
856660 |
|
||||
Control |
1 |
4910 |
26330 |
176776 |
968484 |
|
|||
2 |
4910 |
26404 |
174874 |
908298 |
|
||||
3 |
4910 |
26699 |
176620 |
887413 |
|
||||
4 |
4910 |
22674 |
191186 |
822996 |
|
||||
5 |
4910 |
25392 |
166953 |
756650 |
|
||||
6 |
4910 |
29583 |
169072 |
916118 |
|
||||
Mean |
4910 |
26180 |
175914 |
876660 |
|
Evaluation after 72 hours
Statistically significant differences of growth rates and yield compared to
control values are marked (+), not significant differences are marked (-).
Nominal |
Replicate |
Growth rate |
Rate-related inhibition |
Yield |
Inhibition of yield |
||
[mg/L] |
No. |
[d-1] |
[%] |
[cells/mL] |
[%] |
||
1.00 |
1 |
1.74 |
-0.55 |
894418 |
-2.60 |
||
2 |
1.71 |
1.00 |
824789 |
5.39 |
|||
3 |
1.76 |
-1.61 |
944821 |
-8.38 |
|||
4 |
1.70 |
1.33 |
810978 |
6.97 |
|||
5 |
1.71 |
1.21 |
815886 |
6.41 |
|||
6 |
1.71 |
1.12 |
819610 |
5.98 |
|||
Mean |
(-) |
1.72 |
0.420 |
(-) |
851750 |
2.30 |
|
Control |
1 |
1.76 |
963574 |
||||
2 |
1.74 |
903388 |
|||||
3 |
1.73 |
882503 |
|||||
4 |
1.71 |
818086 |
|||||
5 |
1.68 |
751740 |
|||||
6 |
1.74 |
911208 |
|||||
Mean |
1.73 |
871750 |
Section-by-Section and Average
Specific Growth Rates of the Control Group
(0 – 72 hours)
Replicate No. |
Specific growth rate [d-1] |
Mean (0 - 72 h) |
SD ± |
CV |
Mean CV [%] |
|||
section-by-section |
||||||||
0 - 24 hours |
24 - 48 hours |
48 - 72 hours |
||||||
Control |
1 |
1.68 |
1.90 |
1.70 |
1.76 |
0.124 |
7.04 |
9.78 |
2 |
1.68 |
1.89 |
1.65 |
1.74 |
0.131 |
7.55 |
||
3 |
1.69 |
1.89 |
1.61 |
1.73 |
0.142 |
8.17 |
||
4 |
1.53 |
2.13 |
1.46 |
1.71 |
0.370 |
21.6 |
||
5 |
1.64 |
1.88 |
1.51 |
1.68 |
0.189 |
11.2 |
||
6 |
1.80 |
1.74 |
1.69 |
1.74 |
0.053 |
3.04 |
||
Mean |
1.73 |
|
||||||
SD ± |
0.03 |
|
||||||
CV [%] |
1.70 |
|
NOEC, LOEC, EC - values of the test item (0-72 hours)
based on the saturated solution prepared with 1 mg test item/L
Rate-related Inhibition |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
ErC10 |
> 1.00 |
ErC20 |
> 1.00 |
ErC50 |
> 1.00 |
Inhibition of Yield |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
EyC10 |
< 1.00 |
EyC20 |
> 1.00 |
EyC50 |
> 1.00 |
Cell Densities
|
Replicate |
Cell density [cells/mL] |
|||||||
No. |
0 hours |
24 hours |
48 hours |
72 hours |
|
||||
Saturated solution prepared with 1 mg test item/L |
1 |
4910 |
27542 |
151737 |
633314 |
|
|||
2 |
4910 |
23202 |
156456 |
627729 |
|
||||
3 |
4910 |
24627 |
125747 |
578816 |
|
||||
4 |
4910 |
24505 |
167816 |
862648 |
|
||||
5 |
4910 |
26049 |
151595 |
679317 |
|
||||
6 |
4910 |
27887 |
163422 |
626951 |
|
||||
Mean |
4910 |
25635 |
152796 |
668129 |
|
||||
Control |
1 |
4910 |
27183 |
143295 |
641574 |
|
|||
2 |
4910 |
26059 |
153978 |
890710 |
|
||||
3 |
4910 |
28533 |
168486 |
920227 |
|
||||
4 |
4910 |
28232 |
159570 |
819489 |
|
||||
5 |
4910 |
28814 |
143119 |
754531 |
|
||||
6 |
4910 |
24262 |
140709 |
726707 |
|
||||
Mean |
4910 |
27181 |
151526 |
792206 |
|
Evaluation after 72 hours
Statistically significant differences of growth rates and yield compared to
control values are marked (+), not significant differences are marked (-).
Replicate |
Growth rate |
Rate-related inhibition |
Yield |
Inhibition of yield |
|||
No. |
[d-1] |
[%] |
[cells/mL] |
[%] |
|||
Saturated solution prepared with 1 mg test item/L |
1 |
1.62 |
4.26 |
628404 |
20.2 |
||
2 |
1.62 |
4.44 |
622819 |
20.9 |
|||
3 |
1.59 |
6.03 |
573906 |
27.1 |
|||
4 |
1.72 |
-1.83 |
857738 |
-8.95 |
|||
5 |
1.64 |
2.88 |
674407 |
14.3 |
|||
6 |
1.62 |
4.46 |
622041 |
21.0 |
|||
Mean |
(-) |
1.64 |
3.37 |
(-) |
663219 |
15.8 |
|
Control |
1 |
1.62 |
636664 |
||||
2 |
1.73 |
885800 |
|||||
3 |
1.74 |
915317 |
|||||
4 |
1.71 |
814579 |
|||||
5 |
1.68 |
749621 |
|||||
6 |
1.67 |
721797 |
|||||
Mean |
1.69 |
787296 |
Section-by-Section and Average
Specific Growth Rates of the Control Group
(0-72 hours)
Replicate No. |
Specific growth rate [d-1] |
Mean (0 - 72 h) |
SD ± |
CV |
Mean CV [%] |
|||
section-by-section |
||||||||
0 - 24 hours |
24 - 48 hours |
48 - 72 hours |
||||||
Control |
1 |
1.71 |
1.66 |
1.50 |
1.62 |
0.111 |
6.84 |
4.34 |
2 |
1.67 |
1.78 |
1.76 |
1.73 |
0.0569 |
3.28 |
||
3 |
1.76 |
1.78 |
1.70 |
1.74 |
0.0412 |
2.36 |
||
4 |
1.75 |
1.73 |
1.64 |
1.71 |
0.0609 |
3.57 |
||
5 |
1.77 |
1.60 |
1.66 |
1.68 |
0.0845 |
5.04 |
||
6 |
1.60 |
1.76 |
1.64 |
1.67 |
0.0827 |
4.97 |
||
Mean |
1.69 |
|
||||||
SD ± |
0.05 |
|
||||||
CV [%] |
2.66 |
|
NOEC, LOEC, EC - values of the test item (0-72 hours)
based on nominal concentration [mg/L]
Rate-related Inhibition |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
ErC10 |
> 1.00 |
ErC20 |
> 1.00 |
ErC50 |
> 1.00 |
Inhibition of Yield |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
EyC10 |
> 1.00 |
EyC20 |
> 1.00 |
EyC50 |
> 1.00 |
Cell Densities
|
Nominal |
Replicate |
Cell density [cells/mL] |
||||||
[mg/L] |
No. |
0 hours |
24 hours |
48 hours |
72 hours |
|
|||
1.00 |
1 |
4910 |
24018 |
175395 |
899328 |
|
|||
2 |
4910 |
24065 |
170213 |
829699 |
|
||||
3 |
4910 |
28137 |
174989 |
949731 |
|
||||
4 |
4910 |
22779 |
156551 |
815888 |
|
||||
5 |
4910 |
27027 |
172230 |
820796 |
|
||||
6 |
4910 |
26983 |
145096 |
824520 |
|
||||
Mean |
4910 |
25502 |
165746 |
856660 |
|
||||
Control |
1 |
4910 |
26330 |
176776 |
968484 |
|
|||
2 |
4910 |
26404 |
174874 |
908298 |
|
||||
3 |
4910 |
26699 |
176620 |
887413 |
|
||||
4 |
4910 |
22674 |
191186 |
822996 |
|
||||
5 |
4910 |
25392 |
166953 |
756650 |
|
||||
6 |
4910 |
29583 |
169072 |
916118 |
|
||||
Mean |
4910 |
26180 |
175914 |
876660 |
|
Evaluation after 72 hours
Statistically significant differences of growth rates and yield compared to
control values are marked (+), not significant differences are marked (-).
Nominal |
Replicate |
Growth rate |
Rate-related inhibition |
Yield |
Inhibition of yield |
||
[mg/L] |
No. |
[d-1] |
[%] |
[cells/mL] |
[%] |
||
1.00 |
1 |
1.74 |
-0.55 |
894418 |
-2.60 |
||
2 |
1.71 |
1.00 |
824789 |
5.39 |
|||
3 |
1.76 |
-1.61 |
944821 |
-8.38 |
|||
4 |
1.70 |
1.33 |
810978 |
6.97 |
|||
5 |
1.71 |
1.21 |
815886 |
6.41 |
|||
6 |
1.71 |
1.12 |
819610 |
5.98 |
|||
Mean |
(-) |
1.72 |
0.420 |
(-) |
851750 |
2.30 |
|
Control |
1 |
1.76 |
963574 |
||||
2 |
1.74 |
903388 |
|||||
3 |
1.73 |
882503 |
|||||
4 |
1.71 |
818086 |
|||||
5 |
1.68 |
751740 |
|||||
6 |
1.74 |
911208 |
|||||
Mean |
1.73 |
871750 |
Section-by-Section and Average
Specific Growth Rates of the Control Group
(0 – 72 hours)
Replicate No. |
Specific growth rate [d-1] |
Mean (0 - 72 h) |
SD ± |
CV |
Mean CV [%] |
|||
section-by-section |
||||||||
0 - 24 hours |
24 - 48 hours |
48 - 72 hours |
||||||
Control |
1 |
1.68 |
1.90 |
1.70 |
1.76 |
0.124 |
7.04 |
9.78 |
2 |
1.68 |
1.89 |
1.65 |
1.74 |
0.131 |
7.55 |
||
3 |
1.69 |
1.89 |
1.61 |
1.73 |
0.142 |
8.17 |
||
4 |
1.53 |
2.13 |
1.46 |
1.71 |
0.370 |
21.6 |
||
5 |
1.64 |
1.88 |
1.51 |
1.68 |
0.189 |
11.2 |
||
6 |
1.80 |
1.74 |
1.69 |
1.74 |
0.053 |
3.04 |
||
Mean |
1.73 |
|
||||||
SD ± |
0.03 |
|
||||||
CV [%] |
1.70 |
|
NOEC, LOEC, EC - values of the test item (0-72 hours)
based on the saturated solution prepared with 1 mg test item/L
Rate-related Inhibition |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
ErC10 |
> 1.00 |
ErC20 |
> 1.00 |
ErC50 |
> 1.00 |
Inhibition of Yield |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
EyC10 |
< 1.00 |
EyC20 |
> 1.00 |
EyC50 |
> 1.00 |
Cell Densities
|
Replicate |
Cell density [cells/mL] |
|||||||
No. |
0 hours |
24 hours |
48 hours |
72 hours |
|
||||
Saturated solution prepared with 1 mg test item/L |
1 |
4910 |
27542 |
151737 |
633314 |
|
|||
2 |
4910 |
23202 |
156456 |
627729 |
|
||||
3 |
4910 |
24627 |
125747 |
578816 |
|
||||
4 |
4910 |
24505 |
167816 |
862648 |
|
||||
5 |
4910 |
26049 |
151595 |
679317 |
|
||||
6 |
4910 |
27887 |
163422 |
626951 |
|
||||
Mean |
4910 |
25635 |
152796 |
668129 |
|
||||
Control |
1 |
4910 |
27183 |
143295 |
641574 |
|
|||
2 |
4910 |
26059 |
153978 |
890710 |
|
||||
3 |
4910 |
28533 |
168486 |
920227 |
|
||||
4 |
4910 |
28232 |
159570 |
819489 |
|
||||
5 |
4910 |
28814 |
143119 |
754531 |
|
||||
6 |
4910 |
24262 |
140709 |
726707 |
|
||||
Mean |
4910 |
27181 |
151526 |
792206 |
|
Evaluation after 72 hours
Statistically significant differences of growth rates and yield compared to
control values are marked (+), not significant differences are marked (-).
Replicate |
Growth rate |
Rate-related inhibition |
Yield |
Inhibition of yield |
|||
No. |
[d-1] |
[%] |
[cells/mL] |
[%] |
|||
Saturated solution prepared with 1 mg test item/L |
1 |
1.62 |
4.26 |
628404 |
20.2 |
||
2 |
1.62 |
4.44 |
622819 |
20.9 |
|||
3 |
1.59 |
6.03 |
573906 |
27.1 |
|||
4 |
1.72 |
-1.83 |
857738 |
-8.95 |
|||
5 |
1.64 |
2.88 |
674407 |
14.3 |
|||
6 |
1.62 |
4.46 |
622041 |
21.0 |
|||
Mean |
(-) |
1.64 |
3.37 |
(-) |
663219 |
15.8 |
|
Control |
1 |
1.62 |
636664 |
||||
2 |
1.73 |
885800 |
|||||
3 |
1.74 |
915317 |
|||||
4 |
1.71 |
814579 |
|||||
5 |
1.68 |
749621 |
|||||
6 |
1.67 |
721797 |
|||||
Mean |
1.69 |
787296 |
Section-by-Section and Average
Specific Growth Rates of the Control Group
(0-72 hours)
Replicate No. |
Specific growth rate [d-1] |
Mean (0 - 72 h) |
SD ± |
CV |
Mean CV [%] |
|||
section-by-section |
||||||||
0 - 24 hours |
24 - 48 hours |
48 - 72 hours |
||||||
Control |
1 |
1.71 |
1.66 |
1.50 |
1.62 |
0.111 |
6.84 |
4.34 |
2 |
1.67 |
1.78 |
1.76 |
1.73 |
0.0569 |
3.28 |
||
3 |
1.76 |
1.78 |
1.70 |
1.74 |
0.0412 |
2.36 |
||
4 |
1.75 |
1.73 |
1.64 |
1.71 |
0.0609 |
3.57 |
||
5 |
1.77 |
1.60 |
1.66 |
1.68 |
0.0845 |
5.04 |
||
6 |
1.60 |
1.76 |
1.64 |
1.67 |
0.0827 |
4.97 |
||
Mean |
1.69 |
|
||||||
SD ± |
0.05 |
|
||||||
CV [%] |
2.66 |
|
NOEC, LOEC, EC - values of the test item (0-72 hours)
based on nominal concentration [mg/L]
Rate-related Inhibition |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
ErC10 |
> 1.00 |
ErC20 |
> 1.00 |
ErC50 |
> 1.00 |
Inhibition of Yield |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
EyC10 |
> 1.00 |
EyC20 |
> 1.00 |
EyC50 |
> 1.00 |
Cell Densities
|
Nominal |
Replicate |
Cell density [cells/mL] |
||||||
[mg/L] |
No. |
0 hours |
24 hours |
48 hours |
72 hours |
|
|||
1.00 |
1 |
4910 |
24018 |
175395 |
899328 |
|
|||
2 |
4910 |
24065 |
170213 |
829699 |
|
||||
3 |
4910 |
28137 |
174989 |
949731 |
|
||||
4 |
4910 |
22779 |
156551 |
815888 |
|
||||
5 |
4910 |
27027 |
172230 |
820796 |
|
||||
6 |
4910 |
26983 |
145096 |
824520 |
|
||||
Mean |
4910 |
25502 |
165746 |
856660 |
|
||||
Control |
1 |
4910 |
26330 |
176776 |
968484 |
|
|||
2 |
4910 |
26404 |
174874 |
908298 |
|
||||
3 |
4910 |
26699 |
176620 |
887413 |
|
||||
4 |
4910 |
22674 |
191186 |
822996 |
|
||||
5 |
4910 |
25392 |
166953 |
756650 |
|
||||
6 |
4910 |
29583 |
169072 |
916118 |
|
||||
Mean |
4910 |
26180 |
175914 |
876660 |
|
Evaluation after 72 hours
Statistically significant differences of growth rates and yield compared to
control values are marked (+), not significant differences are marked (-).
Nominal |
Replicate |
Growth rate |
Rate-related inhibition |
Yield |
Inhibition of yield |
||
[mg/L] |
No. |
[d-1] |
[%] |
[cells/mL] |
[%] |
||
1.00 |
1 |
1.74 |
-0.55 |
894418 |
-2.60 |
||
2 |
1.71 |
1.00 |
824789 |
5.39 |
|||
3 |
1.76 |
-1.61 |
944821 |
-8.38 |
|||
4 |
1.70 |
1.33 |
810978 |
6.97 |
|||
5 |
1.71 |
1.21 |
815886 |
6.41 |
|||
6 |
1.71 |
1.12 |
819610 |
5.98 |
|||
Mean |
(-) |
1.72 |
0.420 |
(-) |
851750 |
2.30 |
|
Control |
1 |
1.76 |
963574 |
||||
2 |
1.74 |
903388 |
|||||
3 |
1.73 |
882503 |
|||||
4 |
1.71 |
818086 |
|||||
5 |
1.68 |
751740 |
|||||
6 |
1.74 |
911208 |
|||||
Mean |
1.73 |
871750 |
Section-by-Section and Average
Specific Growth Rates of the Control Group
(0 – 72 hours)
Replicate No. |
Specific growth rate [d-1] |
Mean (0 - 72 h) |
SD ± |
CV |
Mean CV [%] |
|||
section-by-section |
||||||||
0 - 24 hours |
24 - 48 hours |
48 - 72 hours |
||||||
Control |
1 |
1.68 |
1.90 |
1.70 |
1.76 |
0.124 |
7.04 |
9.78 |
2 |
1.68 |
1.89 |
1.65 |
1.74 |
0.131 |
7.55 |
||
3 |
1.69 |
1.89 |
1.61 |
1.73 |
0.142 |
8.17 |
||
4 |
1.53 |
2.13 |
1.46 |
1.71 |
0.370 |
21.6 |
||
5 |
1.64 |
1.88 |
1.51 |
1.68 |
0.189 |
11.2 |
||
6 |
1.80 |
1.74 |
1.69 |
1.74 |
0.053 |
3.04 |
||
Mean |
1.73 |
|
||||||
SD ± |
0.03 |
|
||||||
CV [%] |
1.70 |
|
NOEC, LOEC, EC - values of the test item (0-72 hours)
based on the saturated solution prepared with 1 mg test item/L
Rate-related Inhibition |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
ErC10 |
> 1.00 |
ErC20 |
> 1.00 |
ErC50 |
> 1.00 |
Inhibition of Yield |
|
NOEC |
1.00 |
LOEC |
> 1.00 |
EyC10 |
< 1.00 |
EyC20 |
> 1.00 |
EyC50 |
> 1.00 |
Cell Densities
|
Replicate |
Cell density [cells/mL] |
|||||||
No. |
0 hours |
24 hours |
48 hours |
72 hours |
|
||||
Saturated solution prepared with 1 mg test item/L |
1 |
4910 |
27542 |
151737 |
633314 |
|
|||
2 |
4910 |
23202 |
156456 |
627729 |
|
||||
3 |
4910 |
24627 |
125747 |
578816 |
|
||||
4 |
4910 |
24505 |
167816 |
862648 |
|
||||
5 |
4910 |
26049 |
151595 |
679317 |
|
||||
6 |
4910 |
27887 |
163422 |
626951 |
|
||||
Mean |
4910 |
25635 |
152796 |
668129 |
|
||||
Control |
1 |
4910 |
27183 |
143295 |
641574 |
|
|||
2 |
4910 |
26059 |
153978 |
890710 |
|
||||
3 |
4910 |
28533 |
168486 |
920227 |
|
||||
4 |
4910 |
28232 |
159570 |
819489 |
|
||||
5 |
4910 |
28814 |
143119 |
754531 |
|
||||
6 |
4910 |
24262 |
140709 |
726707 |
|
||||
Mean |
4910 |
27181 |
151526 |
792206 |
|
Evaluation after 72 hours
Statistically significant differences of growth rates and yield compared to
control values are marked (+), not significant differences are marked (-).
Replicate |
Growth rate |
Rate-related inhibition |
Yield |
Inhibition of yield |
|||
No. |
[d-1] |
[%] |
[cells/mL] |
[%] |
|||
Saturated solution prepared with 1 mg test item/L |
1 |
1.62 |
4.26 |
628404 |
20.2 |
||
2 |
1.62 |
4.44 |
622819 |
20.9 |
|||
3 |
1.59 |
6.03 |
573906 |
27.1 |
|||
4 |
1.72 |
-1.83 |
857738 |
-8.95 |
|||
5 |
1.64 |
2.88 |
674407 |
14.3 |
|||
6 |
1.62 |
4.46 |
622041 |
21.0 |
|||
Mean |
(-) |
1.64 |
3.37 |
(-) |
663219 |
15.8 |
|
Control |
1 |
1.62 |
636664 |
||||
2 |
1.73 |
885800 |
|||||
3 |
1.74 |
915317 |
|||||
4 |
1.71 |
814579 |
|||||
5 |
1.68 |
749621 |
|||||
6 |
1.67 |
721797 |
|||||
Mean |
1.69 |
787296 |
Section-by-Section and Average
Specific Growth Rates of the Control Group
(0-72 hours)
Replicate No. |
Specific growth rate [d-1] |
Mean (0 - 72 h) |
SD ± |
CV |
Mean CV [%] |
|||
section-by-section |
||||||||
0 - 24 hours |
24 - 48 hours |
48 - 72 hours |
||||||
Control |
1 |
1.71 |
1.66 |
1.50 |
1.62 |
0.111 |
6.84 |
4.34 |
2 |
1.67 |
1.78 |
1.76 |
1.73 |
0.0569 |
3.28 |
||
3 |
1.76 |
1.78 |
1.70 |
1.74 |
0.0412 |
2.36 |
||
4 |
1.75 |
1.73 |
1.64 |
1.71 |
0.0609 |
3.57 |
||
5 |
1.77 |
1.60 |
1.66 |
1.68 |
0.0845 |
5.04 |
||
6 |
1.60 |
1.76 |
1.64 |
1.67 |
0.0827 |
4.97 |
||
Mean |
1.69 |
|
||||||
SD ± |
0.05 |
|
||||||
CV [%] |
2.66 |
|
Description of key information
In this study (PY120 Nanoform) no inhibition on growth of the freshwater green alga Desmodesmus subspicatus was found after 72 hours exposure to the test item. The NOEC for inhibition of specific growth rate and yield after 72 hours was 1.00 mg/L. All effect levels are given based on the nominal concentration of the test item, which has been analytically verified by HPLC-DAD.
In this study (PY154 bulk) no inhibition on growth of the freshwater green alga Desmodesmus subspicatus was found after 72 hours exposure to the test item. The NOEC for inhibition of specific growth rate and yield after 72 hours was 1.00 mg/L. All effect levels are given based on the nominal concentration of the test item.
Key value for chemical safety assessment
Additional information
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.
![ECHA](/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/echa_logo.png)