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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 224-314-4 | CAS number: 4303-67-7
- 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:
- 15 Sep - 3 Oct 2014
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Statistical variation of results, unstable test substance concentrations
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 2 014
- Report date:
- 2014
Materials and methods
Test guidelineopen allclose all
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 201 (Alga, Growth Inhibition Test)
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- EU Method C.3 (Algal Inhibition test)
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- ISO 8692 (Water Quality - Fresh Water Algal Growth Inhibition Test with Scenedesmus subspicatus and Selenastrum capricornutum)
- GLP compliance:
- yes
Test material
- Reference substance name:
- Laurylimidazole
- IUPAC Name:
- Laurylimidazole
- Details on test material:
- - Name of test material (as cited in study report): MTDID 13999
- Substance type: pure active substance
- Physical state: clear yellowish liquid
- Analytical purity: 99%
- Expiration date of the lot/batch: 23 Sep 2016
- Storage condition of test material: At room temperature in the dark
Constituent 1
Sampling and analysis
- Analytical monitoring:
- yes
- Details on sampling:
- - Concentrations: All test concentrations and controls, at t = 0hr, 24hr, and 72 hrs
- Sampling method: Single 2-mL samples were taken from test chambers. At the end of the exposure period, replicates with algae were pooled at each concentration before sampling
- Sample storage conditions before analysis: in freezer. In a validation study, freezer storage did not affect measured substance concentration
Test solutions
- Vehicle:
- no
- Details on test solutions:
- PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Test substance at 5 mg/L in test medium was stirred for 15 minutes with a magnetic stirrer. This stock solution was then diluted in test medium to make the appropriate test solutions.
- Controls:Blank test medium
- Evidence of undissolved material: Test solutions were clear and colorless
Test organisms
- Test organisms (species):
- Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)
- Details on test organisms:
- TEST ORGANISM
- Common name: Pseudokirchneriella subcapitata
- Strain: NIVA CHL 1
- Source (laboratory, culture collection): In-house laboratory culture
.
- Method of cultivation: Stock cultures were maintained in M1 medium (Nederlandse Praktijk Richtlijn no. 6505).
NaNO3, 500 mg/l
K2HPO4∙3H2O, 52 mg/l
MgSO4∙7H2O, 75 mg/l
Na2CO3∙10H2O, 54 mg/l
C6H8O7∙H2O, 6 mg/l
NH4NO3, 330 mg/l
CaCl2∙2H2O, 35 mg/l
C6H5FeO7∙xH2O, 6 mg/l
H3BO3, 2∙9 mg/l
MnCl2∙4H2O, 1.81 mg/l
ZnCl2, 0.11 mg/l
CuSO4∙5H2O, 0.08 mg/l
(NH4)6Mo7O24∙4H2O, 0.018 mg/l
ACCLIMATION
Four days before the start of the test, cells from the algal stock culture were inoculated in culture medium (M2 according to OECD 201) at a cell density of 1e+04 cells/mL. The pre-culture was maintained under the same conditions as used in the test. The cell density was measured immediately before use.
Study design
- Test type:
- static
- Water media type:
- freshwater
- Limit test:
- no
- Total exposure duration:
- 72 h
Test conditions
- Hardness:
- 24 mg/L as CaCO3
- Test temperature:
- 22.3 - 23.3 °C
- pH:
- 7.7 - 8.2
- Nominal and measured concentrations:
- Nominal: Control, 4.6 µg/L, 10 µg/L, 22 µg/L, 46 µg/L, 100 µg/L
Measured (Time weighted average):- Details on test conditions:
- TEST SYSTEM
- Test vessel: 100 mL all-glass container, 50 mL fill volume
- Agitation: Yes, during incubation the algal cells were kept in suspension by continuous shaking
- Initial cells density: 1E+04 cells/mL
- Control end cells density: 105.5E+04 cells/mL
- No. of vessels per concentration (replicates): 3 (each treatment group, with algae), 1 (intermediate concentration, without algae),
- No. of vessels per control (replicates): 6
GROWTH MEDIUM
- Standard medium used: yes, OECD medium
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Standard medium prepared in reverse osmosis purified water
- Ca/mg ratio: 1
- Culture medium different from test medium: no
OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: no
- Photoperiod: Continuous
- Light intensity and quality: Fluorescent (TL-D) lamps with a light intensity within the range of 83 to 86 μE/(m²∙s). Test vessels were placed randomly and randomly repositioned every day.
EFFECT PARAMETERS MEASURED:
- Determination of cell concentrations: Cells were counted using a microscope and a counting chamber to determine inoculum density. Thereafter, cell densities were determined by spectrophotometric measurement of samples at 720 nm using a spectrophotometer with immersion probe (pathlength =20 mm).
- Appearance: at the end of the test, microscopic examination was done on the test concentration closest to the EC50 to observe for any abnormal appearance of the algae.
TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.2x
- Range finding study: yes
- Test concentrations: Control, 0.10 µg/L, 1.0 µg/L, 10 µg/L, 100 µg/L, 1000 µg/L
- Results used to determine the conditions for the definitive study: EC50 between 10 µg/L and 100 µg/L- Reference substance (positive control):
- yes
- Remarks:
- potassium dichromate (performed ca. 3 weeks prior to tests)
Results and discussion
Effect concentrationsopen allclose all
- Duration:
- 72 h
- Dose descriptor:
- EC50
- Effect conc.:
- 5.57 µg/L
- Nominal / measured:
- meas. (TWA)
- Conc. based on:
- act. ingr.
- Basis for effect:
- growth rate
- Remarks on result:
- other: 95% CI, 4.29 - 7.14 µg/L
- Duration:
- 72 h
- Dose descriptor:
- EC10
- Effect conc.:
- 2.1 µg/L
- Nominal / measured:
- meas. (TWA)
- Conc. based on:
- act. ingr.
- Basis for effect:
- growth rate
- Remarks on result:
- other: 95% CI, 0.85 - 3.10 µg/L
- Details on results:
- - Exponential growth in the control: yes (Table 2, 3)
- Observation of abnormalities: Microscopic observations at the end of the test revealed a normal and healthy appearance of the algal cells exposed to 10 µg/l (nominal) when compared to the control.
- Any stimulation of growth found in any treatment: 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
- Other: Test substance concentration declined throughout the test. This decline was concentration-dependant, and was less pronounced in the algae-free test chamber (Table 1) - Results with reference substance (positive control):
- - Results with reference substance valid? yes
- EC50: 1.7 mg/L. Historical range for the reference substance at the contract lab lies between 0.82 and 2.3 mg/L
- Other: Reference substance toxicity assay conducted ca. 3 weeks prior to test substance. - Reported statistics and error estimates:
- Growth rate data were normally distributed by Shapiro-Wilk's test, p(W) = 0.685 > 0.05. Variance of growth rate data were not homogeneous by Levene's test, p(F) = 0.021 < 0.05. Welch-t test for Inhomogeneous Variances with Bonferroni-Holm Adjustment was used to assess statistical significance of the results. While all results for ≥2.2 µg/L were biologically significant, the statistical significance could not in most cases be assigned due to the high variability in the experimental data (Table 4). The NOEC could not be determined since the lowest test substance concentration had a statistically significant effect. EC10 and EC50 were determined using probit analysis on growth rate data (Table 3)
Any other information on results incl. tables
Table 2, Individual cell densities in the laurylimidazole algal toxicity test |
|||||
Time-weighted average concentration (µg/L) |
Replicate |
Time |
|||
0 h |
24 h |
48 h |
72 h |
||
Control |
1 |
1.0 |
4.817 |
22.526 |
117.14 |
2 |
1.0 |
4.774 |
21.474 |
117.12 |
|
3 |
1.0 |
4.412 |
19.032 |
95.665 |
|
4 |
1.0 |
4.189 |
19.756 |
102.41 |
|
5 |
1.0 |
4.398 |
19.299 |
94.215 |
|
6 |
1.0 |
4.313 |
20.477 |
106.16 |
|
Mean: |
|
1.0 |
4.5 |
20.4 |
105.5 |
Std.Dev.: |
|
0.0 |
0.3 |
1.4 |
10.0 |
CV: |
|
0.0 |
5.7 |
6.6 |
9.5 |
|
|
|
|
|
|
2.2 |
1 |
1.0 |
4.739 |
17.295 |
78.109 |
2 |
1.0 |
4.658 |
18.246 |
79.924 |
|
3 |
1.0 |
4.340 |
14.593 |
54.964 |
|
Mean: |
|
1.0 |
4.6 |
16.7 |
71.0 |
Std.Dev.: |
|
0.0 |
0.2 |
1.9 |
13.9 |
CV: |
|
0.0 |
4.6 |
11.3 |
19.6 |
|
|
|
|
|
|
2.4 |
1 |
1.0 |
3.395 |
8.659 |
20.231 |
2 |
1.0 |
4.040 |
11.202 |
44.955 |
|
3 |
1.0 |
4.689 |
12.968 |
48.063 |
|
Mean: |
|
1.0 |
4.0 |
10.9 |
37.7 |
Std.Dev.: |
|
0.0 |
0.6 |
2.2 |
15.3 |
CV: |
|
0.0 |
16.0 |
19.8 |
40.4 |
|
|
|
|
|
|
5.9 |
1 |
1.0 |
3.308 |
8.318 |
24.817 |
2 |
1.0 |
4.086 |
11.922 |
23.076 |
|
3 |
1.0 |
1.675 |
3.358 |
6.74 |
|
Mean: |
|
1.0 |
3.0 |
7.9 |
18.2 |
Std.Dev.: |
|
0.0 |
1.2 |
4.3 |
10.0 |
CV: |
|
0.0 |
40.7 |
54.7 |
54.8 |
|
|
|
|
|
|
7.0 |
1 |
1.0 |
3.961 |
10.224 |
15.424 |
2 |
1.0 |
3.949 |
3.906 |
5.227 |
|
3 |
1.0 |
1.000 |
1.000 |
1.499 |
|
Mean: |
|
1.0 |
3.0 |
5.0 |
7.4 |
Std.Dev.: |
|
0.0 |
1.7 |
4.7 |
7.2 |
CV: |
|
0.0 |
57.4 |
93.5 |
97.6 |
|
|
|
|
|
|
12.6 |
1 |
1.0 |
1.000 |
1.000 |
1.000 |
2 |
1.0 |
1.658 |
2.560 |
2.446 |
|
3 |
1.0 |
1.000 |
1.000 |
1.083 |
|
Mean: |
|
1.0 |
1.2 |
1.5 |
1.5 |
Std.Dev.: |
|
0.0 |
0.4 |
0.9 |
0.8 |
CV: |
|
0.0 |
31.2 |
59.3 |
53.8 |
Table 3, Growth rates (1/day) in the laurylimidazole algal toxicity test |
|||||
Time-weighted average concentration (µg/L) |
Replicate |
Interval |
|||
0-24 h |
24-48 h |
48-72 h |
0-72 h |
||
Control |
1 |
1.572 |
1.543 |
1.649 |
1.588 |
2 |
1.563 |
1.504 |
1.696 |
1.588 |
|
3 |
1.484 |
1.462 |
1.615 |
1.520 |
|
4 |
1.432 |
1.551 |
1.646 |
1.543 |
|
5 |
1.481 |
1.479 |
1.586 |
1.515 |
|
6 |
1.462 |
1.558 |
1.646 |
1.555 |
|
Mean: |
|
1.499 |
1.516 |
1.639 |
1.551 |
Std.Dev.: |
|
0.056 |
0.040 |
0.037 |
0.032 |
CV: |
|
3.800 |
2.700 |
2.300 |
2.000 |
|
CV = 5% for all section-specific control growth rates |
|
|||
2.2 |
1 |
1.556 |
1.295 |
1.508 |
1.453 |
2 |
1.539 |
1.365 |
1.477 |
1.460 |
|
3 |
1.468 |
1.213 |
1.326 |
1.336 |
|
Mean: |
|
1.521 |
1.291 |
1.437 |
1.416 |
Std.Dev.: |
|
0.047 |
0.076 |
0.097 |
0.070 |
CV: |
|
3.100 |
5.900 |
6.800 |
4.900 |
|
|
|
|
|
|
2.4 |
1 |
1.222 |
0.936 |
0.849 |
1.002 |
2 |
1.396 |
1.020 |
1.390 |
1.269 |
|
3 |
1.545 |
1.017 |
1.310 |
1.291 |
|
Mean: |
|
1.388 |
0.991 |
1.183 |
1.187 |
Std.Dev.: |
|
0.162 |
0.048 |
0.292 |
0.161 |
CV: |
|
11.600 |
4.800 |
24.700 |
13.500 |
|
|
|
|
|
|
5.9 |
1 |
1.196 |
0.922 |
1.093 |
1.071 |
2 |
1.408 |
1.071 |
0.660 |
1.046 |
|
3 |
0.516 |
0.696 |
0.697 |
0.636 |
|
Mean: |
|
1.040 |
0.896 |
0.817 |
0.918 |
Std.Dev.: |
|
0.466 |
0.189 |
0.240 |
0.244 |
CV: |
|
44.800 |
21.100 |
29.400 |
26.600 |
|
|
|
|
|
|
7.0 |
1 |
1.376 |
0.948 |
0.411 |
0.912 |
2 |
1.373 |
-0.011 |
0.291 |
0.551 |
|
3 |
0.000 |
0.000 |
0.405 |
0.135 |
|
Mean: |
|
0.917 |
0.312 |
0.369 |
0.533 |
Std.Dev.: |
|
0.794 |
0.551 |
0.067 |
0.389 |
CV: |
|
86.600 |
176.200 |
18.300 |
73.000 |
|
|
|
|
|
|
12.6 |
1 |
0.000 |
0.000 |
0.000 |
0.000 |
2 |
0.506 |
0.434 |
-0.046 |
0.298 |
|
3 |
0.000 |
0.000 |
0.080 |
0.027 |
|
Mean: |
|
0.169 |
0.145 |
0.011 |
0.108 |
Std.Dev.: |
|
0.292 |
0.251 |
0.063 |
0.165 |
CV: |
|
173.200 |
173.200 |
556.600 |
152.400 |
Table 4, Percentage inhibition of growth rate (total test period) during the final test |
||||
Test substance concentration (TWA, µg/L) |
Mean |
Std. Dev. |
n |
%Inhibition |
Control |
1.551 |
0.0316 |
6 |
0.0 |
2.2 |
1.416 |
0.0699 |
3 |
8.7 * ¹ |
2.4 |
1.187 |
0.1605 |
3 |
23.5 ² |
5.9 |
0.918 |
0.2442 |
3 |
40.9 ² |
7.0 |
0.533 |
0.3889 |
3 |
65.7 ² |
12.6 |
0.108 |
0.1650 |
3 |
93.0 * |
*, effect statistically significant (Welch-t test) 1, effect not biologically significant (<10% effect) 2, effect biologically significant |
Applicant's summary and conclusion
- Validity criteria fulfilled:
- yes
- Conclusions:
- The 72-h EC50 (growth rate) of laurylimidazole to Pseudokirchneriella subcapitata was 5.57 (95% CI, 4.29 - 7.14) µg/L based on time-weighted average concentration (OECD 201). The 72-hour EC10 was 2.10 µg/L (95%, 0.85 - 3.03 µg/L)
- Executive summary:
Toxicity of laurylimidazole to the freshwater alga Pseudokirchneriella subcapitata was assessed according to OECD201. Concentrations between 4.6 µg/L and 100 µg/L were used in the definitive test. Analytically determined concentrations declined throughout the test. Therefore, time-weighted average (TWA) concentrations were used to calculate effect concentration. The 72-hour NOEC (growth rate) could not be determined and was less than the lowest TWA concentration tested (<2.2 µg/L). The 72-hour EC10 was 2.10 µg/L (95%, 0.85 - 3.03 µg/L). The 72-hour EC50 was 5.57 µg/L (95% CI, 4.29 - 7.14 µg/L).
The study was conducted according to internationally accepted test guidelines and in accord with GLP criteria. Test substance concentrations were confirmed analytically. Test substance concentrations were not stable during the test. In addition, the results showed considerable variability. Both difficulties are to be expected given the low concentrations necessary to determine the test substance's toxicity, and its tendency as a surfactant to adsorb to surfaces including the multiplying cells. The study is deemed reliable with restrictions. It is suitable for Risk Assessment, Classification & Labeling, and PBT Analysis.
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.